[go: up one dir, main page]

EP1292284A2 - Encapsulation of polynucleotides and drugs into targeted liposomes - Google Patents

Encapsulation of polynucleotides and drugs into targeted liposomes

Info

Publication number
EP1292284A2
EP1292284A2 EP01942131A EP01942131A EP1292284A2 EP 1292284 A2 EP1292284 A2 EP 1292284A2 EP 01942131 A EP01942131 A EP 01942131A EP 01942131 A EP01942131 A EP 01942131A EP 1292284 A2 EP1292284 A2 EP 1292284A2
Authority
EP
European Patent Office
Prior art keywords
peptide
dna
fusogenic
lipid
liposomes
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
EP01942131A
Other languages
German (de)
French (fr)
Inventor
Teni Boulikas
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Regulon Inc
Original Assignee
Individual
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Individual filed Critical Individual
Publication of EP1292284A2 publication Critical patent/EP1292284A2/en
Ceased legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
    • C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
    • C12N15/00—Mutation or genetic engineering; DNA or RNA concerning genetic engineering, vectors, e.g. plasmids, or their isolation, preparation or purification; Use of hosts therefor
    • C12N15/09—Recombinant DNA-technology
    • C12N15/87—Introduction of foreign genetic material using processes not otherwise provided for, e.g. co-transformation
    • C12N15/88—Introduction of foreign genetic material using processes not otherwise provided for, e.g. co-transformation using microencapsulation, e.g. using amphiphile liposome vesicle
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/127—Synthetic bilayered vehicles, e.g. liposomes or liposomes with cholesterol as the only non-phosphatidyl surfactant
    • A61K9/1271—Non-conventional liposomes, e.g. PEGylated liposomes or liposomes coated or grafted with polymers
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/127—Synthetic bilayered vehicles, e.g. liposomes or liposomes with cholesterol as the only non-phosphatidyl surfactant
    • A61K9/1271—Non-conventional liposomes, e.g. PEGylated liposomes or liposomes coated or grafted with polymers
    • A61K9/1272—Non-conventional liposomes, e.g. PEGylated liposomes or liposomes coated or grafted with polymers comprising non-phosphatidyl surfactants as bilayer-forming substances, e.g. cationic lipids or non-phosphatidyl liposomes coated or grafted with polymers
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P1/00—Drugs for disorders of the alimentary tract or the digestive system
    • A61P1/16—Drugs for disorders of the alimentary tract or the digestive system for liver or gallbladder disorders, e.g. hepatoprotective agents, cholagogues, litholytics
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P25/00—Drugs for disorders of the nervous system
    • A61P25/04—Centrally acting analgesics, e.g. opioids
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P29/00—Non-central analgesic, antipyretic or antiinflammatory agents, e.g. antirheumatic agents; Non-steroidal antiinflammatory drugs [NSAID]
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P3/00—Drugs for disorders of the metabolism
    • A61P3/08—Drugs for disorders of the metabolism for glucose homeostasis
    • A61P3/10—Drugs for disorders of the metabolism for glucose homeostasis for hyperglycaemia, e.g. antidiabetics
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P37/00—Drugs for immunological or allergic disorders
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P7/00—Drugs for disorders of the blood or the extracellular fluid
    • A61P7/04—Antihaemorrhagics; Procoagulants; Haemostatic agents; Antifibrinolytic agents
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/107—Emulsions ; Emulsion preconcentrates; Micelles
    • A61K9/1075—Microemulsions or submicron emulsions; Preconcentrates or solids thereof; Micelles, e.g. made of phospholipids or block copolymers
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/127—Synthetic bilayered vehicles, e.g. liposomes or liposomes with cholesterol as the only non-phosphatidyl surfactant
    • A61K9/1277—Preparation processes; Proliposomes
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61K—PREPARATIONS FOR MEDICAL, DENTAL OR TOILETRY PURPOSES
    • A61K9/00—Medicinal preparations characterised by special physical form
    • A61K9/10—Dispersions; Emulsions
    • A61K9/127—Synthetic bilayered vehicles, e.g. liposomes or liposomes with cholesterol as the only non-phosphatidyl surfactant
    • A61K9/1277—Preparation processes; Proliposomes
    • A61K9/1278—Post-loading, e.g. by ion or pH gradient

Definitions

  • the present invention relates to the field of gene therapy and is specifically directed toward methods for producing peptide-lipid-polynucleotide complexes suitable for delivery of polynucleotides to a subject.
  • the peptide-lipid- polynucleotide complexes so produced are useful in a subject for inhibiting the progression of neoplastic disease.
  • Gene therapy is a newly emerging field of bio edical research that holds great promise for the treatment of both acute and chronic diseases and has the potential to bring a revolutionary era to molecular medicine.
  • routine use of gene therapy for the treatment of human disease has not yet been perfected. It remains an important unmet need of gene therapy to create gene delivery systems that effectively target specific cells of interest in a subject while controlling harmful side effects.
  • Gene therapy is aimed at introducing therapeutically important genes into somatic cells of patients.
  • cancer melanoma, breast, lymphoma, head and neck, ovarian, colon, prostate, brain, chronic myelogenous leukemia, non-small cell lung, lung adenocarcinoma, colorectal, neuroblastoma, glioma, glioblastoma, astrocytoma, and others
  • AIDS cystic fibrosis, adenosine deaminase deficiency
  • cardiovascular diseases restenosis, familial hypercholesterolemia, peripheral artery disease
  • Gaucher disease ⁇ l-antitrypsin deficiency
  • rheumatoid arthritis others.
  • Human diseases expected to be the object of clinical trials include hemophilia A and B, Parkinson's disease, ocular diseases, xeroderma pigmentosum, high blood pressure, obesity.
  • ADA deficiency was the disease successfully treated by the first human "gene transfer" experiment conducted by Kenneth Culver in 1990. See, Culver, K.W. (1996) in: Gene Therapy: A Primer for Physicians, Second Ed., Mary Ann Liebert, Inc. Publ, New York, pp. 1-198.
  • the primary goals of gene therapy are to repair or replace mutated genes, regulate gene expression and signal transduction, manipulate the immune system, or target malignant and other cells for destruction. See, Anderson, W.F. (1992) Science 25(5:808-813; Lasic, D.
  • Human cancer presents a particular disease condition for which effective gene therapy methods would provide a particularly useful clinical benefit.
  • Gene therapy concepts for treatment of such diseases include stimulation of immune responses as well as manipulation of a variety of alternative cellular functions that affect the malignant phenotype.
  • the immune system can be reinforced and instructed to eliminate cancer cells after transduction of a patient's cells ex vivo with the cytokine genes GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN- ⁇ , and TNF- ⁇ , followed by cell vaccination of the patient (e.g. intradermally) to potentiate T-lymphocyte-mediated antitumor effects (cancer immunotherapy).
  • DNA vaccination with genes encoding tumor antigens and immunotherapy with synthetic tumor peptide vaccines are further developments that are currently being tested.
  • the genes used for cancer gene therapy in human clinical trials include a number of tumor suppressor genes (p53, RB, BRCA1, El A), antisense oncogenes (antisense c-fos, c-myc, K-ras), and suicide genes (HSV-tk, in combination with ganciclovir, cytosine deaminase in combination with 5-fluorocytosine).
  • genes that have been proposed for cancer gene therapy include bcl-2, MDR-1, p21, pi 6, bax, bcl-xs, E2F, IGF-I, VEGF, angiostatin, CFTR, LDL-R, TGF- ⁇ , and leptin.
  • One major hurdle preventing successful implementation of these gene therapies is the difficulty of efficiently delivering an effective dose of polynucleotides to the site of the tumor.
  • gene delivery systems with enhanced transfection capabilities would be highly advantageous.
  • a number of different vector technologies and gene delivery methods have been proposed and tested for delivering genes in vivo, including viral vectors and various nucleic acid encapsulation techniques.
  • Alternative viral delivery vehicles for genes include murine retroviruses, recombinant adenoviral vectors, adeno-associated virus, HSV, EBV, HIV vectors, and baculovirus.
  • Nonviral gene delivery methods use cationic or neutral liposomes, direct injection of plasmid DNA, and polymers.
  • Various strategies to enhance efficiency of gene transfer have been tested such as fusogenic peptides in combination with liposomes or polymers to enhance the release of plasmid DNA from endosomes.
  • Adeno-associated virus AAV is not pathogenic and does not elicit immune responses but new production strategies are required to obtain high AAV titers for preclinical and clinical studies. Wild-type AAVs integrate into chromosome 19, whereas recombinant AAVs are deprived of site- specific integration and may also persist episomally.
  • Herpes Simplex Virus (HSV) vectors can infect non-replicating cells, such as neuronal cells, and has a high payload capacity for foreign DNA but inflict cytotoxic effects. It seems that each delivery system will be developed independently of the others and that each will demonstrate strengths and weaknesses for certain applications. At present, retroviruses are most commonly used in human clinical trials, followed by adenoviruses, cationic liposomes and AAV.
  • cell-based gene delivery using polymer-encapsulated syngeneic or allogeneic cells implanted into a tissue of a patient can be used to secrete therapeutic proteins.
  • This method is being tested in trials for amyotrophic lateral sclerosis using the ciliary neurotrophic factor gene, and may be extended to Factor VIII and IX for hemophilia, interleukin genes, dopamine-secreting cells to treat Parkinson's disease, nerve growth factor for Alzheimer's disease and other diseases.
  • Additional methods that have been proposed for improving the efficacy of gene therapy technologies include designing p53 "gene bombs" that explode into tumor cells, exploiting the HIV-1 virus to engineer vectors for gene transfer, combining viruses with polymers or cationic lipids to improve gene transfer, the attachment of nuclear localization signal peptides to oligonucleotides to direct genes to nuclei, and the development of molecular switch systems allowing genes to be turned on or off at will. Nevertheless, because of the wide range of disease conditions for which gene therapies are required, and the complexities of developing treatments for such diseases, there remains a need for improved techniques for performing gene therapy. The present invention provides methods and compositions for addressing these issues.
  • the liposomes are able to reach primary tumors and their metastases after intravenous injection to animals and humans.
  • the method includes micelle formation between DNA with a mixture of cationic lipid and peptide molecules at molar ratios to nearly neutralization ratios in 10-90% ethanol; the cationic peptides specify nuclear localization and have a hydrophobic moiety endowed with membrane fusion to improve entrance across the cell membrane of the complex.
  • the DNA lipid/peptide micelles are converted into liposomes by mixing with pre-made liposomes or lipids followed by dilution in aqueous solutions and dialysis to remove the ethanol and allow liposome formation and extrusion through membranes to a diameter below 160 nm entrapping and encapsulating DNA with a very high yield.
  • the encapsulated DNA has a high therapeutic efficacy in eradicating a variety of solid human tumors including, but not limited to, breast carcinoma and prostate carcinoma.
  • a plasmid is constructed with DNA carrying anticancer genes including, but not limited to p53, RB, BRCA1, E1A, bcl-2, MDR-1, p21, pl6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, EL- 12, IL-2, IL-4, IL-7, IFN- ⁇ , TNF- ⁇ , HSV-tk (in combination with ganciclovir), E. coli cytosine deaminase (in combination with 5-fluorocytosine) and is combined with encapsulated cisplatin or with other similarly systemically delivered antineoplastic drugs to suppress cancer.
  • anticancer genes including, but not limited to p53, RB, BRCA1, E1A, bcl-2, MDR-1, p21, pl6, bax, bcl-xs, E2F, IGF-I VEGF
  • FIG. 1 illustrates the structure of the cancer targeted liposome complex.
  • FIG. 2 illustrates the results of plasmid DNA condensation with various agents as well as various formulation of cationic liposomes in affecting the level of expression of the reporter beta-galactosidase gene after transfection of K562 human erythroleukemia cell cultures.
  • FIG 3 illustrates tumor targeting in SCID mice.
  • FIG 3A shows a SCID mouse with a large and small human breast tumor before and after staining with X-Gal to test the expression of the transferred gene. Both tumors turn dark blue. The intensity of the blue color is proportional to the expression of the beta-galactosidase gene.
  • FIG 3B shows that in the initial staining of the small tumor, the skin and the intestines at the injection area are the first organs to turn blue.
  • FIG 3C is a view of the back of the animal. The two tumors are clearly visible after removal of the skin (top). Dark staining of the small tumor and light blue staining of the large tumor is evident at an initial stage of staining (bottom).
  • FIG 3D is a view of the front side of the animal. The two tumors are clearly visible after removal of the skin. On the figure to the bottom the dark staining of both tumors is evident at a later stage during staining.
  • FIG 3E shows the front (top) and rear (bottom) higher magnification view of the dark staining of both tumors at a later stage during staining. Staining of the vascular system around the small tumor can also be seen (bottom).
  • Table 1 is a list of molecules able to form micelles.
  • Table 2 lists several fusogenic peptides and describes their properties, along with a reference.
  • Table 3 lists simple Nuclear Localization Signal (NLS) peptides.
  • Table 4 shows a list of "bipartite” or “split” NLS peptides.
  • Table 5 lists "nonpositive NLS" peptides lacking clusters of arginines/lysines.
  • NoLS nucleolar localization signals
  • Table 7 lists peptides having karyophilic clusters on non-membrane protein kinases.
  • Table 8 lists peptide nuclear localization signals on DNA repair proteins.
  • Table 9 lists NLS peptides in transcription factors.
  • a cell includes a plurality of cells, including mixtures thereof.
  • compositions and methods include the recited elements, but not excluding others.
  • Consisting essentially of when used to define compositions and methods shall mean excluding other elements of any essential significance to the combination.
  • a composition consisting essentially of the elements as defined herein would not exclude trace contaminants from the isolation and purification method and pharmaceutically acceptable carriers, such as phosphate buffered saline, preservatives, and the like.
  • Consisting of shall mean excluding more than trace elements of other ingredients and substantial method steps for administering the compositions of this invention. Embodiments defined by each of these transition terms are within the scope of this invention.
  • polynucleotide and “nucleic acid molecule” are used interchangeably to refer to polymeric forms of nucleotides of any length.
  • the polynucleotides may contain deoxyribonucleotides, ribonucleotides, and/or their analogs.
  • Nucleotides may have any three-dimensional structure, and may perform any function, known or unknown.
  • polynucleotide includes, for example, single-, double-stranded and triple helical molecules, a gene or gene fragment, exons, introns, mRNA, tRNA, rRNA, ribozymes, cDNA, recombinant polynucleotides, branched polynucleotides, plasmids, vectors, isolated DNA of any sequence, isolated RNA of any sequence, nucleic acid probes, and primers.
  • a nucleic acid molecule may also comprise modified nucleic acid molecules.
  • a "gene” refers to a polynucleotide containing at least one open reading frame that is capable of encoding a particular polypeptide or protein after being transcribed and translated.
  • a “gene product” refers to the amino acid (e.g., peptide or polypeptide) generated when a gene is transcribed and translated.
  • DDAB dimethyldioctadecyl ammonium bromide (same as N,N-distearyl-N,N-dimethylammonium bromide);
  • DODAC N,N-dioleyl-N,N-dimethylammonium chloride;
  • DODAP l,2-dioleoyl-3- dimethylammonium propane;
  • DMRIE N-[l-(2,3-dimyristyloxy)propyl]-N,N- dimethyl-N-(2-hydroxyethyl) ammonium bromide;
  • DMTAP 1 ,2-dimyristoyl-3- trimethylammonium propane;
  • DOGS Dioctadecylamidoglycylspermine;
  • DOTAP (same as DOTMA): N-(l-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride;
  • the term "pharmaceutically acceptable anion” refers to anions of organic and inorganic acids that provide non-toxic salts in pharmaceutical preparations.
  • examples of such anions include the halides anions, chloride, bromide, and iodide, inorganic anions such as sulfate, phosphate, and nitrate, and organic anions.
  • Organic anions may be derived from simple organic acids, such as acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, malic acid, malonic acid, succinic acid, maleic, acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methane sulfonic acid, ethane sulfonic acid, p-toluenesulfonic acid, and the like.
  • the preparation of pharmaceutically acceptable salts is described in Berge, et al., J Pharm. Sci. 66:1-19 (1977), incorporated herein by reference.
  • Physiologically acceptable carriers, excipients or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid; low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, arginine or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA: sugar alcohols such as mannitol or sorbitol; salt-forming counter ions such as sodium; and/or nonionic surfactants such as Tween, Pluronics or polyethylene glycol (PEG).
  • buffers such as phosphate, citrate, and other organic acids
  • antioxidants including ascorbic acid
  • PEG molecules also contain a fusogenic peptide with an attached Nuclear Localization Signal (NLS) covalently linked to the end of the PEG molecule.
  • NLS Nuclear Localization Signal
  • cationic lipid refers to any of a number of lipid species that carry a net positive charge at physiological pH. Such lipids include, but are not limited to, DDAB, DMRIE, DODAC, DOGS, DOTAP, DOSPA and DC-Choi. Additionally, a number of commercial preparations of cationic lipids are available that can be used in the present invention.
  • LIPOFECTIN commercially available cationic liposomes comprising DOTMA and DOPE, from GIBCO/BRL, Grand Island, N.Y., USA
  • LIPOFECTAMLNE commercially available cationic liposomes comprising DOSPA and DOPE, from GIBCO/BRL
  • TRANSFECTAM commercially available cationic lipids comprising DOGS in ethanol from Promega Corp., Madison, Wis., USA.
  • This invention further provides a number of methods for producing micelles with entrapped therapeutic drugs. The method is particularly useful to produce micelles of drugs or compositions having a net overall negative charge, e.g., DNA, RNA or negatively charged small molecules.
  • the DNA can be comprised within a plasmid vector and encode for a therapeutic protein, e.g., wild- type p53, HSV-tk, p21, Bax, Bad, IL-2, IL-12, GM-CSF, angiostatin, endostatin and oncostatin.
  • a therapeutic protein e.g., wild- type p53, HSV-tk, p21, Bax, Bad, IL-2, IL-12, GM-CSF, angiostatin, endostatin and oncostatin.
  • the method requires combining an effective amount of the therapeutic agent with an effective amount of cationic lipids.
  • Cationic lipids useful in the methods of this invention include, but are not limited to, DDAB, dimethyldioctadecyl ammonium bromide; DMRIE: N-[l-(2,3- dimyristyloxy)propyl]-N,N-dimethyl-N-(2-hydroxyethyl) ammonium bromide; DMTAP: l,2-dimyristoyl-3-trimethylammonium propane; DOGS: Dioctadecylamidoglycylspermine; DOTAP (same as DOTMA): N-(l-(2,3- dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride; DPTAP: 1,2- dipalmitoyl-3-trimethylammonium propane; DSTAP: l,2-disteroyl-3- trimethylammonium propane.
  • DDAB dimethyldioctadecyl ammonium bromide
  • a ratio of from about 30 to about 90% of phosphates contained within the negatively charged therapeutic agent are neutralized by positive charges on lipid molecules (negative charges are in excess) to form an electrostatic micelle complex in an effective concentration of ethanol.
  • the ethanol solution is from about 20% to about 80% ethanol. In a further aspect, the ethanol concentration is about 30%.
  • the ethanol/cationic lipid/therapeutic agent complex is then combined with an effective amount of a fusogenic-karyophilic peptide conjugate.
  • an effective amount of the conjugate is a ratio range from about 0.0 to about 0.3 (positive charges on peptide to negative charges on phosphate groups) to neutralize the majority of the remaining negative charges on the phosphate groups of the therapeutic agents thereby leading to an almost complete neutralization of the complex.
  • the optimal conditions give to the complex a slightly negative charge.
  • the excess of positive charges are neutralized by DPPG (dipalmitoyl phosphatidyl glycerol) and its derivatives, or by other anionic lipid molecules in the final micelle complex.
  • the above methods can be modified by addition of DNA condensing agents selected from spermine, spermidine, and magnesium or other divalent metal ions neutralizing a certain percentage (1-20%) of phosphate groups.
  • the cationic lipids are combined with an effective amount of fusogenic lipid DOPE at various molar ratios for example, in a molar ratio of from about 1:1 cationic lipid:DOPE.
  • the cationic lipids are combined with an effective amount of a fusogenic/NLS peptide conjugate.
  • fusogenic/NLS peptide conjugates include, but are not limited to (KAWLKAF) 3 (SEQ ID NO:l), GLFKAAAKLLKSLWKLLLKA (SEQ ID NO:2), LLLKAFAKLLKSLWKLLLKA (SEQ ID NO:3), as well as all derivatives of the prototype (Hydrophobic3-Karyophilicl-Hydrophobic2- Karyophilicl) 2-3 where Hydrophobic is any of the A, I, L, V, P, G, W, F and Karyophilic is any of the K, R, or H, containing a positively-charged residue every 3rd or 4th amino acid, which form alpha helices and direct a net positive charge to the same direction of the helix.
  • GLFKAIAGFIKNGWKGMIDGGGYC SEQ ID NO:4 from influenza virus hemagglutinin HA-2
  • YGRKKRRQRRR SEQ ID NO:5 from TAT of HIV
  • MSGTFGGILAGLIGLL(K/R/H) ⁇ -6 (SEQ ID NO:6), derived from the N-terminal region of the S protein of duck hepatitis B virus, but with the addition of one to six positively-charged lysine, arginine or histidine residues, and combinations of these, able to interact directly with the phosphate groups of plasmid or oligonucleotide DNA, compensating for part of the positive charges provided by the cationic lipids.
  • GAAIGLAWIPYFGPAA (SEQ ID NO:7) is derived from the fusogenic peptide of the Ebola virus transmembrane protein; residues 53-70 (C-terminal helix) of apolipoprotein (apo) All peptide; the 23-residue fusogenic N-terminal peptide of HIV-1 transmembrane glycoprotein gp41; the 29-42 -residue fragment from Alzheimer's ⁇ -amyloid peptide; the fusion peptide and N-terminal heptad repeat of Sendai virus; the 56-68 helical segment of lecithin cholesterol acyltransferase.
  • shorter versions of these peptides that are known to induce fusion of unilamellar lipid vesicles or all that are similarly derivatized with the addition of one to six positively-charged lysine, arginine or histidine residues (K R/H) ⁇ -6 able to interact directly with the phosphate groups of plasmid or oligonucleotide DNA, compensating for part of the positive charges provided by the cationic lipids.
  • the fusogenic peptides in the fusogenic/NLS conjugates represent hydrophobic amino acid stretches, and smaller fragments of these peptide sequences, that include all signal peptide sequences used in membrane or secreted proteins that insert into the endoplasmic reticulum.
  • the conjugates represent transmembrane domains and smaller fragments of these peptide sequences.
  • the NLS peptide component in fusogenic/NLS peptide conjugates is derived from the fusogenic hydrophobic peptides.
  • NLS Localization Signals
  • P proline
  • G glycine
  • Examples of NLS peptides are shown in Tables 1-8.
  • the NLS peptide component in fusogenic/NLS peptide conjugates are synthetic peptides containing the above said NLS, but further modified by additional K, R, H residues at the central part of the peptide or with P or G at the N- or C-terminus.
  • the fusogenic/NLS peptide conjugates are derived from the said fusogenic hydrophobic peptides but with the addition of a stretch of H 4-6 (four to six histidine residues) in the place of NLS.
  • Micelle formation takes place at pH 5-6 where histidyl residues are positively charged but lose their charge at the nearly neutral pH of the biological fluids, thus releasing the plasmid or oligonucleotide DNA from their electrostatic interaction.
  • the fusogenic peptide/NLS peptide conjugates are linked to each other with a short amino acid stretch representing an endogenous protease cleavage site.
  • the structure of the preferred prototype fusogenic/NLS peptide conjugate used in this invention is: PKKRRGPSP(L/A/I) ⁇ 2- 20 (SEQ ID NO:8), where (L/A/I) 12-20 is a stretch of 12-20 hydrophobic amino acids containing A, L, I, Y, W, F and other hydrophobic amino acids.
  • the micelles made by the above methods are further provided by this invention by conversion into liposomes.
  • An effective amount of liposomes (diameter from about 80 to about 160 nm), or of a lipid solution composed of cholesterol (from about 10% to about 50%), neutral phospholipid such as hydrogenated soy phosphatidylcholine (HSPC) (from about 40% to about 90%), and the derivatized vesicle-forming lipid PEG-DSPE (distearoylphosphatidyl ethanolamine) from about 1-to about 7 mole percent, is added to the micelle solution.
  • HSPC hydrogenated soy phosphatidylcholine
  • PEG-DSPE disivatized vesicle-forming lipid PEG-DSPE
  • the liposomes are composed of vesicle-forming lipids and between from about 1 to about 7 mole percent of distearoylphosphatidyl ethanolamine (DSPE) derivatized with a polyethyleneglycol.
  • DSPE distearoylphosphatidyl ethanolamine
  • Micelles are converted into liposomes with a concomitant decrease of the ethanol concentration which can be accomplished by removal of the ethanol by dialysis of the liposome complexes through permeable membranes or reduced to a diameter of 80-160 nm by extrusion through membranes.
  • Liposome encapsulated therapeutic agents produced by the above methods are further provided by this invention.
  • a method for delivering a therapeutic agent such as plasmid DNA or oligonucleotides to a tissue cell in vivo by intravenous, or other type of injection of the micelles or liposomes This method specifically targets a primary tumor and the metastases by the long circulating time of the micelle or liposome complex because of the exposure of PEG chains on its surface, its small size (80-160 nm) and the decrease in hydrostatic pressure in the solid tumor from the center to its periphery supporting a preferential extravasation through the tumor vasculature to the extracellular space in tumors.
  • a method for delivering plasmid or oligonucleotide DNA across the cell membrane barrier of the tumors using the micelle or liposome complexes described herein is capable because of the presence of the fusogenic peptides in the complex.
  • a method for delivering plasmid or oligonucleotide DNA to the liver, spleen and bone marrow after intravenous injection of the complexes is provided.
  • a method for delivering therapeutic genes to the liver, spleen and bone marrow of cancer and noncancer patients including but not limited to, factor VIII or IX for the therapy of hemophilias, multidrug resistance, cytokine genes for cancer immunotherapy, genes for the alleviation of pain, genes for the alleviation of diabetes and genes that can be introduced to liver, spleen and bone marrow tissue, to produce a secreted form of a therapeutic protein.
  • the disclosed therapies also provide methods for reducing tumor size by combining the encapsulated plasmid DNA carrying one or more anticancer genes selected from the group consisting of p53, RB, BRCA1, El A, bcl-2, MDR-1, p21, pi 6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN- ⁇ , TNF- ⁇ , HSV-tk (in combination with ganciclovir), E.
  • anticancer genes selected from the group consisting of p53, RB, BRCA1, El A, bcl-2, MDR-1, p21, pi 6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, IL-12, IL-2, IL-4,
  • coli cytosine deaminase in combination with 5-fluorocytosine
  • encapsulated antisense oligonucleotides antisense c-fos, c-myc, K-ras
  • ribozymes or triplex-forming oligonucleotides directed against genes that control the cell cycle or signaling pathways.
  • encapsulated plasmid DNA carrying one or more anticancer genes of can be modified by combining the encapsulated plasmid DNA carrying one or more anticancer genes of with encapsulated or free antineoplastic drugs, consisting of the group of adriamycin, angiostatin, azathioprine, bleomycin, busulfane, camptothecin, carboplatin, carmustine, chlorambucile, chlormethamine, chloroquinoxaline sulfonamide, cisplatin, cyclophosphamide, cycloplatam, cytarabine, dacarbazine, dactinomycin, daunorubicin, didox, doxorubicin, endostatin, enloplatin, estramustine, etoposide, extramustinephosphat, flucytosine, fluorodeoxyuridine, fluorouracil, gallium nitrate, hydroxyurea, idoxuridine,
  • Liposomes are microscopic vesicles consisting of concentric lipid bilayers. Structurally, liposomes range in size and shape from long tubes to spheres, with dimensions from a few hundred Angstroms to fractions of a millimeter. Vesicle- forming lipids are selected to achieve a specified degree of fluidity or rigidity of the final complex providing the lipid composition of the outer layer.
  • DOPE dioleoylphosphatidylethanolamine
  • lipids capable of producing a stable liposome are phospholipids, such as hydrogenated soy phosphatidylcholine (HSPC), lecithin, phosphatidylethanolamine, lysolecithin, lysophosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, cephalin, cardiolipin, phosphatidic acid, cerebrosides, distearoylphosphatidylethanolamine (DSPE), dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC), palmitoyloleoylphosphatidylcholine (POPC), palmitoyloleoylphosphatidylethanolamine (POPE) and dioleoylphosphatidylethanolamine 4-(N-maleimido-methyl)cyclohexane
  • HSPC hydrogenated soy phosphati
  • Additional non-phosphorous containing lipids that can become incorporated into liposomes include stearylamine, dodecylamine, hexadecylamine, isopropyl myristate, triethanolamine-lauryl sulfate, alkyl-aryl sulfate, acetyl palmitate, glycerol ricinoleate, hexadecyl stereate, amphoteric acrylic polymers, polyethyloxylated fatty acid amides, and the cationic lipids mentioned above (DDAB, DODAC, DMRIE, DMTAP, DOGS, DOTAP (DOTMA), DOSPA, DPTAP, DSTAP, DC-Chol).
  • DDAB DODAC
  • DMRIE DMTAP
  • DOGS DOGS
  • DOTAP DOTMA
  • DOSPA DPTAP
  • DSTAP DC-Chol
  • Negatively charged lipids include phosphatidic acid (PA), dipalmitoylphosphatidylglycerol (DPPG), dioleoylphosphatidylglycerol and (DOPG), dicetylphosphate that are able to form vesicles.
  • Preferred lipids for use in the present invention are cholesterol, hydrogenated soy phosphatidylcholine (HSPC) and, the derivatized vesicle-forming lipid PEG-DSPE.
  • liposomes can be divided into three categories based on their overall size and the nature of the lamellar structure.
  • MLVs multi-lamellar vesicles
  • SUVs small uni-lamellar vesicles
  • LUVs large uni-lamellar vesicles
  • SUVs range in diameter from approximately 20 to 50 nm and consist of a single lipid bilayer surrounding an aqueous compartment.
  • Unilamellar vesicles can also be prepared in sizes from about 50 nm to 600 nm in diameter.
  • MLVs While unilamellar are single compartmental vesicles of fairly uniform size, MLVs vary greatly in size up to 10,000 nm, or thereabouts, are multi -compartmental in their structure and contain more than one bilayer. LUV liposomes are so named because of their large diameter that ranges from about 600 nm to 30,000 nm; they can contain more than one bilayer. Liposomes may be prepared by a number of methods not all of which produce the three different types of liposomes. For example, ultrasonic dispersion by means of immersing a metal probe directly into a suspension of MLVs is a common way for preparing SUVs.
  • Preparing liposomes of the MLV class usually involves dissolving the lipids in an appropriate organic solvent and then removing the solvent under a gas or air stream. This leaves behind a thin film of dry lipid on the surface of the container. An aqueous solution is then introduced into the container with shaking, in order to free lipid material from the sides of the container. This process disperses the lipid, causing it to form into lipid aggregates or liposomes.
  • Liposomes of the LUV variety may be made by slow hydration of a thin layer of lipid with distilled water or an aqueous solution of some sort. Alternatively, liposomes may be prepared by lyophilization. This process comprises drying a solution of lipids to a film under a stream of nitrogen.
  • This film is then dissolved in a volatile solvent, frozen, and placed on a lyophilization apparatus to remove the solvent.
  • a solution of the drug is added to the lyophilized lipids, whereupon liposomes are formed.
  • Cationic Liposome/Cationic Peptide/Nucleic Acid Micelles Cationic lipids, with the exception of sphingosine and some lipids in primitive life forms, do not occur in nature.
  • the present invention uses single-chain amphiphiles which are chloride and bromide salts of the alkyltrimethylammonium surfactants including but not limited to C12 and C16 chains abbreviated DDAB (same as DODAB) or CTAB.
  • DDAB chloride and bromide salts of the alkyltrimethylammonium surfactants including but not limited to C12 and C16 chains abbreviated DDAB (same as DODAB) or CTAB.
  • DDAB chloride and bromide salts of the alkyltrimethylammonium surfactants
  • CTAB C12 and C16 chains
  • the molecular geometry of these molecules determines the critical micelle concentration (ratio between free monomers in solution and molecules in micelles).
  • Lipid exchange between the two states is a highly dynamic process; phospholipids have critical micelle concentration values below IO "8 M and are more stable in liposomes; however, single chain detergents, such as stearylamine, may emerge from the liposome membrane upon dilution or intravenous injection in milliseconds (Lasic, 1997).
  • Cationic lipids include, but are not limited to, DDAB: dimethyldioctadecyl ammonium bromide (same as N,N-distearyl-N,N-dimethylammonium bromide); DMRIE: N-[l-(2,3-dimyristyloxy)propyl]-N,N-dimethyl-N-(2-hydroxyethyl) ammonium bromide; DODAC: N,N-dioleyl-N,N-dimethylammonium chloride; DMTAP: l,2-dimyristoyl-3-trimethylammonium propane; DODAP: l,2-dioleoyl-3- dimethylammonium propane; DOGS: Dioctadecylamidoglycylspermine; DOTAP (same as DOTMA): N-(l-(2,3-dioleoyloxy)propyl)-N,N,N-tri
  • Lipid-based vectors used in gene transfer have been formulated in one of two ways.
  • the nucleic acid is introduced into preformed liposomes made of mixtures of cationic lipids and neutral lipids.
  • the complexes thus formed have undefined and complicated structures and the transfection efficiency is severely reduced by the presence of serum.
  • Preformed liposomes are commercially available as LLPOFECTLN and LIPOFECTAMLNE.
  • the second method involves the formation of DNA complexes with mono- or poly-cationic lipids without the presence of a neutral lipid. These complexes are prepared in the presence of ethanol and are not stable in water. Additionally, these complexes are adversely affected by serum (see, Behr, Ace. Chem. Res.
  • the nucleotide polymers can be single-stranded DNA or RNA, or double- stranded DNA or DNA-RNA hybrids.
  • double-stranded DNA include structural genes, genes including control and termination regions, and self- replicating systems such as plasmid DNA.
  • Particularly preferred nucleic acids are plasmids.
  • Single-stranded nucleic acids include antisense oligonucleotides (complementary to DNA and RNA), ribozymes and triplex-forming oligonucleotides.
  • nucleotide linkages substituted with stable, non-phosphodiester linkages, including, for example, phosphorothioate, phosphorodithioate, phosphoroselenate, methylphosphonate, or O-alkyl phosphotriester linkages.
  • Cationic lipids used with fusogenic peptide/NLS conjugates to provide the inner layer of the particle can be any of a number of substances selected from the group of DDAB, DODAC, DMRIE, DMTAP, DOGS, DOTAP (DOTMA), DOSPA, DPTAP, DSTAP, DC-Chol.
  • the cationic lipid is combined with DOPE.
  • the preferred cationic lipid is DDAB :DOPE 1:1.
  • Neutral lipids used herein to provide the outer layer of the particles can be any of a number of lipid species that exist either in an uncharged or neutral zwitterionic form at physiological pH.
  • Such lipids are selected from a group consisting of diacylphosphatidylcholine, diacylphosphatidylethanolamine, ceramide, sphingomyelin, cephalin, and cerebrosides.
  • lipids containing saturated, mono-, or di-unsaturated fatty acids with carbon chain lengths in the range of C14 to C22 are preferred. In general, less saturated lipids are more easily sized, particularly when the liposomes must be sized below about 0.16 microns, for purposes of filter sterilization.
  • lipids having a variety of acyl chain groups of varying chain length and degree of saturation are available or may be isolated or synthesized by well-known techniques.
  • lipids with carbon chain lengths in the range of C 14 to C22 are used.
  • the neutral lipids used in the present invention are hydrogenated soy phosphatidylcholine (HSPC), cholesterol, and PEG- distearoylphosphatidyl ethanolamine (DSPE) or PEG-ceramide.
  • Preparing liposomes of the MLV class usually involves dissolving the lipids in an appropriate organic solvent and then removing the solvent under a gas or air stream. This leaves behind a thin film of dry lipid on the surface of the container. An aqueous solution is then introduced into the container with shaking, in order to free lipid material from the sides of the container. This process disperses the lipid, causing it to form into lipid aggregates or liposomes.
  • Liposomes of the LUV variety may be made by slow hydration of a thin layer of lipid with distilled water or an aqueous solution of some sort. Alternatively, liposomes may be prepared by lyophilization. This process comprises drying a solution of lipids to a film under a stream of nitrogen.
  • the film is then dissolved in a volatile solvent, frozen, and placed on a lyophilization apparatus to remove the solvent.
  • a solution of the drug is added to the lyophilized lipids, whereupon liposomes are formed.
  • the liposomes may be sized to achieve a desired size range and relatively narrow distribution of liposome sizes.
  • the preformed liposomes are sized to a mean diameter of about 80 to 160 nm (the upper size limit for filter sterilization before in vivo administration).
  • Sonicating a liposome suspension either by bath or probe sonication produces a progressive size reduction down to small unilamellar vesicles less than about 0.05 microns (50 nm) in size.
  • Extrusion of liposome through a small-pore polycarbonate is our preferred method for reducing liposome sizes to a relatively well-defined size distribution.
  • the liposomes may be extruded through successively smaller-pore membranes, to achieve a gradual reduction in liposome size.
  • compositions comprising the cationic liposome/nucleic acid complexes of the invention are prepared according to standard techniques and further comprise a pharmaceutically acceptable carrier. Generally, normal saline will be employed as the pharmaceutically acceptable carrier.
  • the pharmaceutical compositions are preferably administered parenterally, i.e., intravenously, intraperitoneally, subcutaneously, intrathecally, injection to the spinal cord, intramuscularly, intraarticularly, portal vein injection, or mtratumorally. More preferably, the pharmaceutical compositions are administered intravenously or mtratumorally by a bolus injection.
  • the pharmaceutical preparations may be contacted with the target tissue by direct application of the preparation to the tissue. The application may be made by topical "open” or "closed” procedures.
  • topical means the direct application of the pharmaceutical preparation to a tissue exposed to the environment, such as the skin, to any surface of the body, nasopharynx, external auditory canal, ocular administration and administration to the surface of any body cavities, inhalation to the lung, genital mucosa and the like.
  • Open procedures are those procedures that include incising the skin of a patient and directly visualizing the underlying tissue to which the pharmaceutical preparations are applied. This is generally accomplished by a surgical procedure, such as a thoracotomy to access the lungs, abdominal laparotomy to access abdominal viscera, or other direct surgical approach to the target tissue.
  • “Closed” procedures are invasive procedures in which the internal target tissues are not directly visualized, but accessed via insertion of instruments through small wounds in the skin.
  • the preparations may be administered to the peritoneum by needle lavage.
  • the pharmaceutical preparations may be administered to the meninges or spinal cord by infusion during a lumbar puncture followed by appropriate positioning of the patient as commonly practiced for spinal anesthesia or metrazamide imaging of the spinal cord.
  • the preparations may be administered through endoscopic devices.
  • DDAB dioleoylphosphatidylethanolamine
  • DOPE dioleoylphosphatidylethanolamine
  • PEG-DSPE was from Syngena.
  • the pGL3-C (Promega) was cut with Xbal and blunt-end ligated using the Klenow fragment of E. coli DNA polymerase. It was then cut with Hindlll and the 1689-bp fragment, carrying the luciferase gene, was gel-purified.
  • the pGFP-Nl plasmid (Clontech) was cut with Smal and Hindlll and the 4.7 kb fragment, isolated from an agarose gel, was ligated with the luciferase fragment. JM109 E.
  • Radiolabeled plasmid pLF was generated by culturing Escherichia coli in
  • this invention provides a method for entrapping DNA into lipids that enhances the content of plasmid per volume unit, and reduces the toxicity of the cationic lipids used to trap plasmid or oligonucleotide DNA.
  • the DNA becomes hidden in the inner membrane bilayer of the final complex.
  • the gene transfer complex is endowed with long circulation time in body fluids and extravasates preferentially into solid tumors and their metastatic foci and nodules. The extravasation occurs through their vasculature at most sites of the human or animal body after intravenous injection of the gene-carrying vehicles.
  • a suitable solvent for preparing a micelle from the desired lipid components is ethanol, methanol, or other aliphatic alcohols such as propanol, isopropanol, butanol, tert-butanol, iso-butanol, pentanol and hexanol. Mixtures of two or more solvents may be used in the practice of the invention. It is also to be understood that any solvent that is miscible with an ethanol solution, even in small amounts, can be used to improve micelle formation and its subsequent conversion into liposomes, including chloroform, dichloromethane, diethylether, cyclohexane, cyclopentane, benzene, and toluene.
  • the liposome encapsulated DNA described herein further comprises an effective amount of cationic lipids.
  • Cationic lipids have been widely used for gene transfer; a number of clinical trials (34 out of 220 total RAC- approved protocols as of December, 1997) use cationic lipids. Although many cell culture studies have been documented, systemic delivery of genes with cationic lipids in vivo has been very limited. All clinical protocols use subcutaneous, intradermal, intratumoral, and intracranial injection as well as intranasal, intrapleural, or aerosol administration but not IV. delivery, because of the toxicity of the cationic lipids and DOPE (see, Martin and Boulikas, 1998).
  • Liposomes formulated from DOPE and cationic lipids based on diacyltrimethylammonium propane (dioleoyl-, dimyristoyl-, dipalmitoyl-, disteroyl-trimethylammonium propane or DOTAP, DMTAP, DPTAP, DSTAP, respectively) or DDAB were highly toxic when incubated in vitro with phagocytic cells (macrophages and U937 cells), but not towards non-phagocytic T lymphocytes.
  • the rank order of toxicity was DOPE/DDAB > DOPE/DOTAP > DOPE/DMT AP > DOPE/DPTAP > DOPE/DSTAP; and the toxicity was determined from the effect of the cationic liposomes on the synthesis of nitric oxide (NO) and TNF- ⁇ produced by activated macrophages (Filion and Phillips, 1997).
  • NO nitric oxide
  • TNF- ⁇ produced by activated macrophages
  • Condensing agents used for plasmid delivery including polylysine, transferrin-polylysine, a fifth-generation poly(amidoamine) (PAMAM) dendrimer, poly(ethyleneimine), and several cationic lipids (DOTAP, DC-Chol/DOPE, DOGS/DOPE, and DOTMA/DOPE), were found to activate the complement system to varying extents. Strong complement activation was seen with long-chain polylysines, the dendrimer, poly(ethyleneimine), and DOGS. Modifying the surface of preformed DNA complexes with polyethyleneglycol (Plank et al., 1996) considerably reduced complement activation.
  • Cationic lipids increase the transfection efficiency by destabilizing the biological membranes, including plasma, endosomal, and lysosomal membranes.
  • Incubation of isolated lysosomes with low concentrations of DOTAP caused a striking increase in free activity of ⁇ -galactosidase, and even a release of the enzyme into the medium.
  • the mechanism of destabilization was thought to involve an interaction between cationic liposomes and anionic lipids of the lysosomal membrane, thus allowing a fusion between the lipid bilayers.
  • CHOL was only about 50% charged as monitored by a pH-sensitive fluorophore. This difference decreases the charge on the external surfaces of the liposomes, and was proposed to promote an easier dissociation of bilayers containing DC-CHOL from the plasmid DNA, and an increase in release of the DNA-lipid complex into the cytosol from the endosomes (Zuidam and Barenholz, 1997).
  • cationic lipids have been used widely for the delivery of genes, very few studies have used systemic I.V. injection of cationic liposome-plasmid complexes. This is because of the toxicity of the lipid component in animal models, not humans.
  • a number of different organs in vivo can be targeted after liposomal delivery of genes or oligonucleotides.
  • Intravenous injection of cationic liposome-plasmid complexes by tail vein in mice targeted mainly the lung and to a smaller extent the liver, spleen, heart, kidney and other organs (Zhu et al., 1993).
  • DOTAP:cholesterol/DNA complex preparation A number of factors for DOTAP:cholesterol/DNA complex preparation including the DNA:liposome ratio, mild sonication, heating, and extrusion were found to be crucial for improved systemic delivery; maximal gene expression was obtained when a homogeneous population of DNA:liposome complexes between 200 to 450 nm in size were used. Cryo-electron microscopy showed that the DNA was condensed on the interior of invaginated liposomes between two lipid bilayers in these formulations, a factor that was thought to be responsible for the high transfection efficiency in vivo and for the broad tissue distribution (Templeton et al., 1997).
  • Steps to improve liposome-mediated gene delivery to somatic cells include, persistence of the plasmid in blood circulation, port of entry and transport across the cell membrane, release from endosomal compartments into the cytoplasm, nuclear import by docking through the pore complexes of the nuclear envelope, expression driven by the appropriate promoter/enhancer control elements, and persistence of the plasmid in the nucleus for long periods (Boulikas, 1998a).
  • the liposome encapsulated DNA described herein is condensed with spermine and/or spermidine.
  • DNA can be presented to cells in culture as a complex with polycations such as polylysine, or basic proteins such as protamine, total histones or specific histone fractions, protamine (Boulikas and Martin, 1997).
  • polycations such as polylysine, or basic proteins such as protamine, total histones or specific histone fractions, protamine (Boulikas and Martin, 1997).
  • the interaction of plasmid DNA with protamine sulfate, followed by the addition of DOTAP cationic liposomes offered a better protection of plasmid DNA against enzymatic digestion.
  • the method gave consistently higher gene expression in mice via tail vein injection as compared with DOTAP/DNA complexes.
  • luciferase-plasmid 50 ⁇ g of luciferase-plasmid per mouse gave 20 ng luciferase protein per mg extracted tissue protein in the lung, that was detected as early as 1 h after injection, peaked at 6 h and declined thereafter.
  • Intraportal injection of protamine/DOTAP/DNA led to about a 100-fold decrease in gene expression in the lung as compared with I.V. injection.
  • Endothelial cells were the primary locus of lacZ transgene expression (Li and Huang, 1997).
  • Protamine sulfate enhanced plasmid delivery into several different types of cells in vitro, using the monovalent cationic liposomal formulations (DC-Chol and lipofectin). This effect was less pronounced with the multivalent cationic liposome formulation, lipofectamine (Sorgi et al., 1997).
  • the liposome encapsulates oligonucleotide DNA.
  • Encapsulation of oligonucleotides into liposomes increased their therapeutic index, prevented degradation in cultured cells, and in human serum and reduced toxicity to cells (Thierry and Dritschilo, 1992; Capaccioli et al., 1993; Lewis et al., 1996).
  • most studies have been performed in cell culture, and very few in animals in vivo. There are still an important number of improvements needed before these approaches can move into clinical studies.
  • oligonucleotides were redistributed from punctate cytoplasmic regions into the nucleus. This process was independent of acidification of the endosomal vesicles.
  • the nuclear uptake of oligonucleotides depended on several factors, such as charge of the particle, where positively charged complexes were required for enhanced nuclear uptake.
  • DOTAP increased over 100 fold the antisense activity of a specific anti-luciferase oligonucleotide.
  • oligonucleotide-DD AB/DOPE complexes with a net positive charge were released from vesicles into the cytoplasm. It was determined that DD AB/DOPE mediated nuclear import of the oligonucleotides.
  • DOPE-heme (ferric protoporphyrin IX) conjugates inserted in cationic lipid particles with DOTAP, protected oligoribonucleotides from degradation in human serum and increased oligoribonucleotide uptake into 2.2.15 human hepatoma cells. The enhancing effect of heme was evident only at a net negative charge in the particles (Takle et al., 1997). Uptake of liposomes labeled with ] ' ] In and composed of DC-Chol and DOPE was primarily by liver, with some accumulation in spleen and skin and very little in the lung after I.V. tail injection.
  • oligonucleotide Preincubation of cationic liposomes with phosphorothioate oligonucleotide induced a dramatic, yet transient, accumulation of the lipid in lung that gradually redistributed to liver.
  • the mechanism of lung uptake involved entrapment of large aggregates of oligonucleotides within pulmonary capillaries at 15 min post-injection via embolism. Labeled oligonucleotide was localized primarily to phagocytic vacuoles of Kupffer cells at 24 h post-injection. Nuclear uptake of oligonucleotides in vivo was not observed (Litzinger et al., 1996).
  • the liposome encapsulated DNA described herein further comprise coating of the final complex in step 2 (Fig. 1) with PEG.
  • PEG polyethylene glycol
  • Derivatized lipids that are employed include PEG- modified DSPE or PEG-ceramide. Addition of PEG components prevents complex aggregation, increases circulation lifetime of particles (liposomes, proteins, other complexes, drugs) and increases the delivery of lipid-nucleic acid complexes to the target tissues. See, Maxfield et al., Polymer 7(5:505-509 (1975); Bailey, F.E.
  • the concentration of the PEG-modified phospholipids, or PEG-ceramide in the complex will be about 1-7%.
  • the PEG-modified lipid is a PEG-DSPE.
  • the PEG hydrophilic polymers form dense "conformational clouds” to prevent other macromolecules from interaction with the surface, even at low concentrations of the protecting polymer (Gabizon and Papahadjopoulos, 1988; Papahadjopoulos et al., 1991; reviewed by Torchilin, 1998).
  • the increased hydrophilicity of the liposomes after their coating with the amphipathic PEG5000 leads to a reduction in nonspecific uptake by the reticuloendothelial system.
  • mice Micelles, surfactants and small unilamellar vesicles
  • the liposome encapsulated DNA described herein further comprise an initial step of micelle formation between cationic lipids and condensed plasmid or oligonucleotide DNA in ethanol solutions.
  • Micelles are small amphiphilic colloidal particles formed by certain kinds of lipid molecules, detergents or surfactants under defined conditions of concentration, solvent and temperature. They are composed of a single lipid layer. Micelles can have their hydrophilic head groups assembled exposing their hydrophobic tails to the solvent (for example in 30- 60% aqueous ethanol solution) or can reverse their structures exposing their polar heads toward the solvent such as by lowering the concentration of the ethanol to below 10% (reverse micelles). Micelle systems are in thermodynamic equilibrium with the solvent molecules and environment.
  • Single-chain surfactants are able to form micelles (see Table 1, below). These include the anionic (sodium dodecyl sulfate, cholate or oleate) or cationic (cetyl-trimethylammonium bromide, CTAB) surfactants.
  • CTAB, CTAC, and DOIC micelles yielded larger solubility gaps (lower concentration of colloidally suspended DNA) than corresponding SUV particles containing neutral lipid and CTAB (1:1) (Lasic, 1997).
  • Table 1 Molecules able to form micelles
  • HLB hydrophile/lipophile balance
  • Nonionic surfactants include, nonionic esters such as ethylene glycol esters, propylene glycol esters, glyceryl esters, polyglyceryl esters, sorbitan esters, sucrose esters, and ethoxylated esters.
  • nonionic alkanolamides and ethers such as fatty alcohol ethoxylates, propoxylated alcohols, and ethoxylated/propoxylated, block polymers are also included in this class.
  • the polyoxyethylene surfactants are the most popular members of the nonionic surfactant class.
  • Anionic surfactants include carboxylates such as soaps, acyl lactylates, acyl amides of amino acids, esters of sulfuric acid such as alkyl sulfates and ethoxylated alkyl sulfates, sulfonates such as alkyl benzene sulfonates, acyl isethionates, acyl taurates and sulfosuccinates, and phosphates.
  • the most important members of the anionic surfactant class are the alkyl sulfates and the soaps.
  • Cationic surfactants include quaternary ammonium salts and ethoxylated amines.
  • the quatemary ammonium salts are the most used members of this class. If the surfactant molecule has the ability to carry either a positive or negative charge, the surfactant is classified as amphoteric.
  • Amphoteric surfactants include acrylic acid derivatives, substituted alkylamides, N-alkylbetaines and phosphatides.
  • Classical micelles may not be effective as gene transfer vehicles, but important intermediates in the formation of liposome complexes encapsulating drugs or nucleic acids.
  • the stability of single chain surfactants-DNA-colloidal systems is lower than SUV particles containing neutral lipid and CTAB (1:1).
  • second generation micelles are able to target tumors in vivo.
  • Weissig and co- workers (1998) used the soybean trypsin inhibitor (STI) as a model protein to target tumors.
  • STI was modified with a hydrophobic residue of N-glutaryl-phosphatidyl- ethanolamine (NGPE) and incorporated into both polyethyleneglycol (MW 5000)- distearoyl phosphatidyl ethanolamine (PEG-DSPE) micelles ( ⁇ 20 nm) and PEG- DSPE-modified long-circulating liposomes (ca. 100 nm).
  • N-glutaryl-phosphatidyl- ethanolamine NGPE
  • PEG-DSPE polyethyleneglycol
  • PEG-DSPE distearoyl phosphatidyl ethanolamine
  • DTP A protein-attached diethylene triamine pentaacetic acid
  • PEG-lipid micelles accumulated better than the same protein anchored in long-circulating PEG-liposomes in subcutaneously established Lewis lung carcinoma in mice after tail vein injection.
  • Loading a liposomal dispersion with an amphiphilic drug may cause a phase transformation into a micellar solution.
  • the transition from high ratios of phospholipid to drug (from 2:1 to 1:1 downwards) were accompanied by the conversion of liposomal dispersions of milky- white appearance (particle size 200 nm) to nearly transparent micelles (particle size below 25 nm). See, Schutze and Muller-Goymann (1998).
  • the liposome encapsulated DNA described herein further comprises an effective amount of a fusogenic peptide.
  • Fusogenic peptides belong to a class of helical amphipathic peptides characterized by a hydrophobicity gradient along the long helical axis. This hydrophobicity gradient causes the tilted insertion of the peptides in membranes, thus destabilizing the lipid core and, thereby, enhancing membrane fusion (Decout et al., 1999).
  • Hemagglutinin (HA) is a homotrimeric surface glycoprotein of the influenza virus. In infection, it induces membrane fusion between viral and endosomal membranes at low pH.
  • Each monomer consists of the receptor-binding HA1 domain and the membrane-interacting HA2 domain.
  • the NH 2 -terminal region of the HA2 domain (amino acids 1 to 127), the so-called “fusion peptide,” inserts into the target membrane and plays a crucial role in triggering fusion between the viral and endosomal membranes.
  • fusion peptide inserts into the target membrane and plays a crucial role in triggering fusion between the viral and endosomal membranes.
  • fusogenic peptides from influenza virus hemagglutinin HA-2 enhanced greatly the efficiency of transferrin-polylysine- DNA complex uptake by cells.
  • the peptide was linked to polylysine and the complex was delivered by the transferrin receptor-mediated endocytosis (reviewed by Boulikas, 1998a).
  • This peptide has the sequence: GLFEAIAGFI ENGWEGMIDG GGYC (SEQ ID NO:9) and is able to induce the release of the fluorescent dye calcein from liposomes prepared with egg yolk phosphatidylcholine, which was higher at acidic pH.
  • This peptide was also able to increase up to 10- fold the anti-HIV potency of antisense oligonucleotides, at a concentration of 0.1-1 mM, using CEM-SS lymphocytes in culture.
  • This peptide changes conformation at the slightly more acidic environment of the endosome, destabilizing and breaking the endosomal membrane (reviewed by Boulikas, 1998a).
  • the presence of negatively charged lipids in the membrane is important for the manifestation of the fusogenic properties of some peptides, but not of others.
  • HA-chimeras were designed in which the cytoplasmic tail and/or transmembrane domain of HA was replaced with the corresponding domains of the fusogenic glycoprotein F of Sendai virus.
  • Constructs of HA were made in which the cytoplasmic tail was replaced by peptides of human neurofibromin type 1 (NFl) (residues 1441 to 1518) or c-Raf-1, (residues 51 to 131) and were expressed in CV-1 cells by using the vaccinia virus-T7 polymerase transient-expression system.
  • NFl human neurofibromin type 1
  • c-Raf-1 c-Raf-1
  • Membrane fusion between CV-1 cells and bound human erythrocytes (RBCs) mediated by parental or chimeric HA proteins showed that, after the pH was lowered, a flow of the aqueous fluorophore calcein from preloaded RBCs into the cytoplasm of the protein-expressing CV-1 cells took place. This indicated that membrane fusion involves both leaflets of the lipid bilayers and leads to formation of an aqueous fusion pore (Schroth-Diaz et al., 1998).
  • TAT protein of HIV is able to cross cell membranes (Green and Loewenstein, 1998) and that a 36-amino acid domain of TAT, when chemically cross-linked to heterologous proteins, conferred the ability to transduce into cells.
  • the 11 -amino acid fusogenic peptide of TAT (YGRKKRRQRRR (SEQ ID NO: 10)) is a nucleolar localization signal (see Boulikas, 1998b).
  • Another protein of HIV contains fusogenic peptides.
  • Linear peptides derived from the membrane proximal region of the gp41 ectodomain have potential applications as anti-HIV agents and inhibit infectivity by adopting a helical conformation (Judice et al., 1997).
  • the 23 amino acid residue, N-terminal peptide of HIV-1 gp41 has the capacity to destabilize negatively charged large unilamellar vesicles. In the absence of cations, the main structure was a pore- forming alpha-helix, whereas in the presence of Ca 2+ the conformation switched to a fusogenic, predominantly extended beta-type structure.
  • PrP The prion protein
  • the prion protein (PrP) is a glycoprotein of unknown function normally found at the surface of neurons and of glial cells. It is involved in diseases such as bovine spongiform encephalopathy, and Creutzfeldt- Jakob disease in humans, where PrP is converted into an altered form (termed PrPSc).
  • PrPSc The 120 to 133 and 118 to 135 domains of PrP are tilted lipid- associating peptides inserting in a oblique way into a lipid bilayer and able to interact with liposomes to induce leakage of encapsulated calcein (Pillot et al., 1997b).
  • the C-terminal fragments of the Alzheimer amyloid peptide (amino acids 29-
  • HEXXH SEQ ID NO:l 1
  • a recognized zinc-binding motif is in a helicoidal conformation (Martin et al., 1999; Melino et al, 1999; Curtain et al., 1999).
  • Fusion peptides have been formulated with DNA plasmids to create peptide- based gene delivery systems.
  • DOPE is a fusogenic lipid; elastase cleavage of N-methoxy-succinyl- Ala- Ala-Pro- Val-DOPE (SEQ ID NO: 19) converted this derivative to DOPE (overall positive charge) to deliver an encapsulated fluorescent probe, calcein, into the cell cytoplasm (Pak et al., 1999).
  • oligodeoxynucleic sequence of 30 bases complementary to a region of beta-endorphin mRNA elicited a concentration- dependent inhibition of beta-endorphin production in cell culture after it was 0 encapsulated within small unilamellar vesicles (50 nm) containing dipalmitoyl-DL- alpha-phosphatidyl-L-serine endowed with fusogenic properties (Fresta et al., 1998).
  • the liposome encapsulated plasmid or 5 oligonucleotide DNA described herein further comprise an effective amount of nuclear localization signal (NLS) peptides.
  • NLS nuclear localization signal
  • Protein translocation from the cytoplasm to the nucleoplasm involves: (i) the formation of a complex of karyopherin ⁇ with NLS-protein; (ii) subsequent binding of karyopherin ⁇ ; (iii) binding of the complex to FXFG peptide repeats on nucleoporins; (iv) docking of Ran-GDP to nucleoporin and to karyopherin heterodimer by plO; (v) a number of association-dissociation reactions on nucleoporins that dock the import substrate toward the nucleoplasmic side with a concomitant GDP-GTP exchange reaction transforming Ran-GDP into Ran-GTP and catalyzed by karyopherin ⁇ ; and (vi) dissociation from karyopherin ⁇ and release of the karyopherin ⁇ /NLS-protein by Ran-GTP to the nucleoplasm.
  • Karyophilic and acidic clusters were found in most non-membrane serine/threonine protein kinases whose primary structure has been examined (Table 6). These karyophilic clusters might mediate the anchoring of the kinase molecules to transporter proteins for their regulated nuclear import and might constitute the nuclear localization signals.
  • protein transcription factors that are exclusively nuclear possessing strong karyophilic peptides composed of at least four arginines, (R), and lysines, (K), within an hexapeptide flanked by proline and glycine helix-breakers, protein kinases often contain one histidine and three K+R residues (Boulikas, 1996).
  • NLS nuclear localization of a protein of an unknown function from its amino acid sequence:
  • R arginines
  • K lysines
  • H histidines
  • the K/R clusters are flanked by the ⁇ -helix breakers G and P thus placing the NLS at a helix-turn-helix or end of a ⁇ -helix.
  • Negatively-charged amino acids (D, E) are often found at the flank of the NLS and on some occasions may interrupt the positively-charged NLS cluster;
  • NLS signals may not be flanked by long stretches of hydrophobic amino acids (e.g. five); a mixture of charged and hydrophobic amino acids serves as a mitochondrial targeting signal;
  • a number of processes have been found to be regulated by nuclear import including nuclear translocation of the transcription factors NF- ⁇ B, rNFIL-6, ISGF3, SRF, c-Fos, GR as well as human cyclins A and Bl, casein kinase II, cAMP- dependent protein kinase II, protein kinase C, ERK1 and ERK2.
  • Failure of cells to import specific proteins into nuclei can lead to carcinogenesis.
  • BRCA1 is mainly localized in the cytoplasm in breast and ovarian cancer cells, whereas in normal cells the protein is nuclear.
  • mRNA is exported through the same route as a complex with nuclear proteins possessing nuclear export signals (NES).
  • RNA-binding proteins that bind to and escort RNAs to the cytoplasm.
  • CRM1 that binds to the NES sequence on other proteins and interacts with the nuclear pore complex, is an essential mediator of the NES-dependent nuclear export of proteins in eukaryotic cells.
  • Nuclear localization and export signals are found on a number of important molecules, including p53, v-Rel, the transcription factor NF-ATc, the c-Abl nonreceptor tyrosine kinase, and the fragile X syndrome mental retardation gene product. The deregulation of their normal import/export trafficking has important implications for human disease.
  • Both nuclear import and export processes can be manipulated by conjugation of proteins with NLS or NES peptides.
  • the foreign DNA needs to enter nuclei for its transcription.
  • a pathway is proposed involving the complexation of plasmids and oligonucleotides with nascent nuclear proteins possessing NLSs as a prerequisite for their nuclear import.
  • Covalent linkage of NLS peptides to oligonucleotides and plasmids or formation of complexes of plasmids with proteins possessing multiple NLS peptides was proposed (Boulikas, 1998b) to increase their import rates and the efficiency of gene expression. Cancer cells were predicted to import more efficiently foreign DNA into nuclei, compared with terminally differentiated cells because of their increased rates of proliferation and protein import.
  • the liposome encapsulated plasmid or oligonucleotide DNA described herein further comprises its use for reducing tumor size or restricting its growth with combination with encapsulated or free antineoplastic agents.
  • Antineoplastic agents preferably are: (i) alkylating agents having the bis-(2-chloroethyl)-amine group such as chlormethine, chlorambucile, melphalan, uramustine, mannomustine, extramustinephosphat, mechlorethaminoxide, cyclophosphamide, ifosfamide, or trifosfamide; (ii) alkylating agents having a substituted aziridine group, for example tretamine, thiotepa, triaziquone, or mitomycine; (iii) alkylating agents of the methanesulfonic ester type such as busulfane; (iv) alkylating N-alkyl-N-nitros
  • tumor suppressor genes p53, RB, BRCA1, E1A, bcl-2, MDR-1, p21, pl6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN- ⁇ , and TNF- ⁇ ); and (xxiii) antisense oligonucleotides (antisense c-fos, c-myc, K-ras).
  • these drugs are administered in combination with chlormethamine, prednisolone, prednisone, or procarbazine or combined with radiation therapy.
  • Future new anticancer drugs added to the arsenal are expected to be ribozymes, triplex-forming oligonucleotides, gene inactivating oligonucleotides, a number of new genes directed against genes that control the cell proliferation or signaling pathways, and compounds that block signal transduction.
  • Anti-cancer drugs include: acivicin, aclarubicin, acodazole hydrochloride, acronine, adozelesin, adriamycin, aldesleukin, altretamine, ambomycin, ametantrone acetate, aminoglutethimide, amsacrine, anastrozole, anthramycin, asparaginase, asperlin, azacitidine, azetepa, azotomycin, batimastat, benzodepa, bicalutamide, bisantrene hydrochloride, bisnafide dimesylate, bizelesin, bleomycin sulfate, brequinar sodium, bropirimine, busulfan, cactinomycin, calusterone, caracemide, carbetimer, carboplatin, carmustine, carubicin hydrochloride, carzelesin, cedefingol, chlorambucil
  • anti-cancer drugs include: 20-epi-l,25 dihydroxyvitamin D3, 5- ethynyluracil, abiraterone, aclarubicin, acylfulvene, adecypenol, adozelesin, aldesleukin, ALL-TK antagonists, altretamine, ambamustine, amidox, amifostine, aminolevulinic acid, amrubicin, amsacrine, anagrelide, anastrozole, andrographolide, angiogenesis inhibitors, antagonist D, antagonist G, antarelix, anti-dorsalizing morphogenetic protein- 1, antiandrogen, antiestrogen, antineoplaston, antisense oligonucleotides, aphidicolin glycinate, apoptosis gene modulators, apoptosis regulators, apurinic acid, ara-CDP-DL-PTBA, arginine deaminas
  • the genes in plasmid DNA are brought in interaction with fusogenic peptide/NLS conjugates.
  • the NLS moiety is a stretch of histidyl residues able to assume a net positive charge at a pH of about 5 to 6 and to show a reduction or loose completely this charge at pH above 7. The electrostatic interaction of these positively-charged peptides with the negatively-charged plasmid DNA molecules, established at pH 5-6 is weakened at physiological pH (pH-sensitive peptide-DNA complexes).
  • the first step of the present invention involves complex formation between the plasmid or oligonucleotide DNA with the histidyl/fusogenic peptide conjugate and lipid components in 10-90% ethanol at pH 5.0 to 6.0.
  • the conditions must be where the histidyl residues have a net positive charge and can establish electrostatic interactions with plasmids, oligonucleotides or negatively-charged drugs.
  • the presence of the positively-charged lipid molecules promotes formation of micelles.
  • micelles are converted into liposomes by dilution with water and mixing with pre-made liposomes or lipids at pH 5-6.
  • composition of peptides and cationic lipids in the first step provides the lipids of the internal bilayer
  • the type of liposomes or lipids added at step 2 provide the external coating of the final liposome formulation ( Figure 1).
  • formulations of peptides include: HHHHHSPSL 16 (SEQ ID NO:623), and HHHHHSPS(LAI) 5 (SEQ ID NO:624).
  • the peptide inserts in an alpha-helical conformation inside the lipid bilayer and not only carries out DNA condensation but also endows membrane fusion properties to the complex to improve entrance across the cell membrane.
  • the type of hydrophobic amino acids for example, content in aromatic amino acids, in the peptide chain is very important as is the length of the peptide chain in ensuring integrity and rigidity of the complexes.
  • An important issue of the present invention is the conversion of micelles formed between the DNA and the cationic lipids, in the presence of ethanol, into liposomes. This is done by the direct addition of the micelle complex into an aqueous solution of preformed liposomes.
  • the liposomes have an average size of 80-160 nm or vice versa, leading to a solution of a final ethanol concentration below 10%.
  • a formulation suitable for pharmaceutical use and for injection into humans and animals will require that the liposomes are of neutral composition (such as cholesterol, PE, PC) coated with PEG.
  • the composition of the aqueous solution of liposomes is any type of liposomes containing cationic lipids and suitable therefore for transfection of cells in culture such as DDAB:DOPE 1:1.
  • These liposomes are pre-formed and downsized by sonication or extrusion through membranes to a diameter of 80-160 nm.
  • the ethanolic micelle preparations are then added to the aqueous solution of liposomes with a concomitant dilution of the ethanol solution to below 10%. This step will result in further condensation of DNA or interaction of the negatively-charged phosphate groups on DNA with positively charged groups on lipids. Care must be taken so as only part of the negative charges on DNA are neutralized by lipids in the micelle.
  • the remaining charge neutralization of the DNA is to be provided by the cationic component of the preformed liposomes in the second step.
  • the genes in plasmid DNA are driven by regulatory DNA sequences isolated from nuclear matrix-attached DNA using shotgun selection approaches.
  • the compact structural organization of chromatin and the proper spatial orientation of individual chromosomes within a cell are partially provided by the nuclear matrix.
  • the nuclear matrix is composed of DNA, RNA and proteins and serves as the site of DNA replication, gene transcription, DNA repair, and chromosomal attachment in the nucleus. Diverse sets of DNA sequences have been found associated with nuclear matrices and is referred to as matrix attachment regions or MARs.
  • the MARs serve many functions, acting as activators of gene transcription, silencers of gene expression, insulators of transcriptional activity, nuclear retention signals and origins of DNA replication.
  • Current studies indicate that different subsets of MARs are found in different tissue types and may assist in regulating the specific functions of cells.
  • the presence of this complex assortment of structural and regulatory molecules in the matrix, as well as the in situ localization of DNA replication and transcription complexes to the matrix strongly suggest that the nuclear matrix plays a fundamental, unique role in nuclear processes.
  • the structuring of genomes into domains has a functional significance.
  • the inclusion of specific MAR elements within gene transfer vectors could have utility in many experimental and gene therapy applications. Many gene therapy applications require specific expression of one or more genes in targeted cell types for prolonged time periods.
  • MARs within vectors could enhance transcription of the introduced transgene, prolong the retention of that sequence within the nucleus or insulate expression of that transgene from the expression of a cotransduced gene (reviewed by Boulikas, 1995; Bode et al, 1996).
  • Various biochemical procedures have been used to identify regulatory regions within genes. Traditionally, identification and selection of regulatory DNA sequences depend on tedious procedures such as transcription factor footprinting in vitro or in vivo, or subcloning of smaller fragments from larger genomic DNA sequences upstream of reporter genes. These methods have been used primarily to identify regions proximal to the 5' end of genes.
  • regulatory regions are found at considerable distances from the proximal 5' end of the gene, and confer cell type- or developmental stage- specificity.
  • studies from the groups of Grosveld and Engel have shown that over 625 kb of genomic sequences surrounding the GATA-3 locus are required for the correct developmental expression of the gene in transgenic mice.
  • the presently disclosed method has the potential of rapidly identifying regulatory control regions.
  • chromatin loops are formed and different attachment regions are used in different cell types or stages of development to modulate the expression of a gene.
  • the presently disclosed method for isolating regulatory regions based on their attachment to the nuclear matrix can identify regulatory regions irrespective of their distance from the gene.
  • Example 1 Plasmid DNA condenses with various agents, as well as various formulations of cationic liposomes. The condensation affects the level of expression of the reporter beta-galactosidase gene after transfection of K562 human erythroleukemia cell cultures. Liposome compositions are shown in the Table below and in FIG. 2. All lipids were from Avanti Polar Lipids (700 Industrial Park Drive, Alabaster, AL 35007). The optimal ratio oflipid to DNA was 7 nmoles total lipid/ ⁇ g DNA.
  • the transfection reagent (10 ⁇ g DNA mixed with 70 nmoles total lipid) was transferred to a small culture flask followed by the addition of 10 ml K562 cell culture (about 2 million cells total); mixing of cells with the transfection reagent was at 5-10 min after mixing DNA with liposomes. Cells were assayed for beta-galactosidase activity several times at 1-30 days post-transfection. The transfected cells were maintained in cell culture as normal cell cultures.
  • plasmid solution (10 ⁇ g total plasmid DNA) 20 ⁇ l or 50 ⁇ l of polyK, polyR, polyH, were added; the volume was adjusted to 250 ⁇ l with water followed by addition of about 70 ⁇ l liposomes (7 nmoles / ⁇ g DNA). After incubation for 10 min to 1 h at 20°C the transfection mixture was brought in contact with the cell culture.
  • the best DNA condensing reagent was polyhistidine compared with the popular polylysine.
  • the best cationic lipid was DC-cholesterol (DC-CHOL: 3 ⁇ pSf-(N',N'-dimethylaminoethane)carbamoyl]cholesterol).
  • SFV is Semliki Forest virus expressing beta-galactosidase. The results are shown in FIG. 2.
  • DOPE (mw 744) DOPE 1.3 ⁇ mole/ml + 0.25 ml DOPE (20 mg/ml)
  • SCID severe combined immunodeficient mice
  • the cells were allowed to develop into large, measurable solid tumors at about 30 days post-inoculation.
  • Mice were injected intraperitoneously with 0.2 mg plasmid pCMV ⁇ DNA (size of the plasmid is ⁇ 4 kb) per animal carrying the bacterial beta-galactosidase reporter gene.
  • Plasmid DNA (200 ⁇ g, 2.0 mg/ml, 0.1 ml ) was incubated for 5 min with 200 ⁇ l neutral liposomes of the composition 40% cholesterol, 20% dioleoylphosphatidylethanolamine(DOPE), 12% palmitoyloleoylphosphatidylcholine (POPC), 10% hydrogenated soy phosphatidylcholine (HSPC), 10% distearoylphosphatidylethanolamine (DSPE), 5% sphingomyelin (SM), and 3% derivatized vesicle-forming lipid M-PEG-DSPE.
  • DOPE dioleoylphosphatidylethanolamine
  • POPC palmitoyloleoylphosphatidylcholine
  • HSPC hydrogenated soy phosphatidylcholine
  • DSPE distearoylphosphatidylethanolamine
  • SM sphingomyelin
  • the material was injected (0.35 ml total volume) to the intraperitoneal cavity of the animal. At 5 days post-injection the animal was sacrificed, the skin was removed and the carcass was incubated into X-gal staining solution for about 30 min at 37°C. The animal was incubated in fixative in X-gal staining for about 30 min (addition of 100 ⁇ l concentrated glutaraldehyde to 30 ml X-gal staining solution) and the incubation in staining solution continued. Photos were taken in a time course during the incubation period revealing the preferred organs where beta-galactosidase expression took place.
  • the data imply that transfer of the genes of angiostatin, endostatin, or oncostatin to the tumors (whose gene products restrict vascular growth and inhibit blood supply to the tumor) is expected to be a rational approach for cancer treatment. Also, a combination therapy using anticancer lipogenes with encapsulated drugs into tumor targeting liposomes appears as a rational cancer therapy.
  • Boulikas, T. (1997c) "Nuclear localization signal peptides for the import of plasmid DNA in gene therapy” Int. J. Oncol. 70:301-309.
  • Boulikas, T. (1998a) "Status of gene therapy in 1997: Molecular mechanisms, disease targets, and clinical applications” Gene Tfier. Mol. Biol. 7:1-172.
  • Boulikas, T. (1998b) "Nucleocytoplasmic trafficking: implications for the nuclear import of plasmid DNA during gene therapy” Gene Ther. Mol. Biol. 7:713- 740.
  • Torchilin, V.P. (1998) "Polymer-coated long-circulating microparticulate pharmaceuticals" J. Microencapsul. 75:1-19. Torchilin, V.P. et al. (1992) "Targeted accumulation of polyethylene glycol-coated immunoliposomes in infarcted rabbit myocardium" FASEB J. 5:2716-2719.

Landscapes

  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Organic Chemistry (AREA)
  • Veterinary Medicine (AREA)
  • Public Health (AREA)
  • Medicinal Chemistry (AREA)
  • Animal Behavior & Ethology (AREA)
  • Pharmacology & Pharmacy (AREA)
  • Engineering & Computer Science (AREA)
  • Nuclear Medicine, Radiotherapy & Molecular Imaging (AREA)
  • Bioinformatics & Cheminformatics (AREA)
  • General Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Diabetes (AREA)
  • Genetics & Genomics (AREA)
  • Biomedical Technology (AREA)
  • General Engineering & Computer Science (AREA)
  • Dispersion Chemistry (AREA)
  • Epidemiology (AREA)
  • Pain & Pain Management (AREA)
  • Zoology (AREA)
  • Wood Science & Technology (AREA)
  • Molecular Biology (AREA)
  • Hematology (AREA)
  • Biotechnology (AREA)
  • Biophysics (AREA)
  • Endocrinology (AREA)
  • Immunology (AREA)
  • Neurosurgery (AREA)
  • Neurology (AREA)
  • Plant Pathology (AREA)
  • Microbiology (AREA)
  • Emergency Medicine (AREA)
  • Biochemistry (AREA)
  • Physics & Mathematics (AREA)
  • Obesity (AREA)
  • Rheumatology (AREA)
  • Gastroenterology & Hepatology (AREA)

Abstract

A method is disclosed for encapsulating plasmids, oligonucleotides or negatively-charged drugs into liposomes having a different lipid composition between their inner and outer membrane bilayers and able to reach primary tumors and their metastases after intravenous injection to animals and humans. The formulation method includes complex formation between DNA with cationic lipid molecules and fusogenic/NLS peptide conjugates composed of a hydrophobic chain of about 10-20 amino acids and also containing four or more histidine residues or NLS at their one end. The encapsulated molecules display therapeutic efficacy in eradicating a variety of solid human tumors including but not limited to breast carcinoma and prostate carcinoma. Combination of the plasmids, oligonucleotides or negatively-charged drugs with other anti-neoplastic drugs (the positively-charged cis-platin, doxorubicin) encapsulated into liposomes are of therapeutic value. Also of therapeutic value in cancer eradication are combinations of encapsulated the plasmids, oligonucleotides or negatively-charged drugs with HSV-tk plus encapsulated ganciclovir.

Description

ENCAPSULATION OF PLASMID DNA (LIPOGENES™) AND THERAPEUTIC AGENTS WITH NUCLEAR LOCALIZATION SIGNAL/FUSOGENIC PEPTIDE CONJUGATES INTO TARGETED LIPOSOME COMPLEXES
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Serial No. 60/210,925 filed June 9, 2000. The contents of this application is hereby incorporated by reference into the present disclosure.
FIELD OF THE INVENTION
The present invention relates to the field of gene therapy and is specifically directed toward methods for producing peptide-lipid-polynucleotide complexes suitable for delivery of polynucleotides to a subject. The peptide-lipid- polynucleotide complexes so produced are useful in a subject for inhibiting the progression of neoplastic disease.
BACKGROUND OF THE INVENTION Throughout this application various publications, patents and published patent specifications are referenced by author and date or by an identifying patent number. Full bibliographical citations for the publications are provided immediately preceding the claims. The disclosures of these publications, patents and published patent specifications are hereby incorporated by reference into the present disclosure to more fully describe the state of the art to which this invention pertains.
Gene therapy is a newly emerging field of bio edical research that holds great promise for the treatment of both acute and chronic diseases and has the potential to bring a revolutionary era to molecular medicine. However, despite numerous preclinical and clinical studies, routine use of gene therapy for the treatment of human disease has not yet been perfected. It remains an important unmet need of gene therapy to create gene delivery systems that effectively target specific cells of interest in a subject while controlling harmful side effects. Gene therapy is aimed at introducing therapeutically important genes into somatic cells of patients. Diseases already shown to be amenable to therapy with gene transfer in clinical trials include, cancer (melanoma, breast, lymphoma, head and neck, ovarian, colon, prostate, brain, chronic myelogenous leukemia, non-small cell lung, lung adenocarcinoma, colorectal, neuroblastoma, glioma, glioblastoma, astrocytoma, and others), AIDS, cystic fibrosis, adenosine deaminase deficiency, cardiovascular diseases (restenosis, familial hypercholesterolemia, peripheral artery disease), Gaucher disease, αl-antitrypsin deficiency, rheumatoid arthritis and others. Human diseases expected to be the object of clinical trials include hemophilia A and B, Parkinson's disease, ocular diseases, xeroderma pigmentosum, high blood pressure, obesity. ADA deficiency was the disease successfully treated by the first human "gene transfer" experiment conducted by Kenneth Culver in 1990. See, Culver, K.W. (1996) in: Gene Therapy: A Primer for Physicians, Second Ed., Mary Ann Liebert, Inc. Publ, New York, pp. 1-198. The primary goals of gene therapy are to repair or replace mutated genes, regulate gene expression and signal transduction, manipulate the immune system, or target malignant and other cells for destruction. See, Anderson, W.F. (1992) Science 25(5:808-813; Lasic, D. (1997) in: Liposomes in Gene Delivery, CRC Press, pp. 1- 295; Boulikas, T. (1998) Gene Ther. Mol. Biol. 7:1-172; Martin, F. and Boulikas, T. (1998) Gene Ther. Mol. Biol. 7:173-214; Ross, G. et al. (1996) Hum. Gene Ther. 7:1781-1790.
Human cancer presents a particular disease condition for which effective gene therapy methods would provide a particularly useful clinical benefit. Gene therapy concepts for treatment of such diseases include stimulation of immune responses as well as manipulation of a variety of alternative cellular functions that affect the malignant phenotype. Although many human tumors are non or weakly immunogenic, the immune system can be reinforced and instructed to eliminate cancer cells after transduction of a patient's cells ex vivo with the cytokine genes GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN-γ, and TNF-α, followed by cell vaccination of the patient (e.g. intradermally) to potentiate T-lymphocyte-mediated antitumor effects (cancer immunotherapy). DNA vaccination with genes encoding tumor antigens and immunotherapy with synthetic tumor peptide vaccines are further developments that are currently being tested. The genes used for cancer gene therapy in human clinical trials include a number of tumor suppressor genes (p53, RB, BRCA1, El A), antisense oncogenes (antisense c-fos, c-myc, K-ras), and suicide genes (HSV-tk, in combination with ganciclovir, cytosine deaminase in combination with 5-fluorocytosine). Other important genes that have been proposed for cancer gene therapy include bcl-2, MDR-1, p21, pi 6, bax, bcl-xs, E2F, IGF-I, VEGF, angiostatin, CFTR, LDL-R, TGF-β, and leptin. One major hurdle preventing successful implementation of these gene therapies is the difficulty of efficiently delivering an effective dose of polynucleotides to the site of the tumor. Thus, gene delivery systems with enhanced transfection capabilities would be highly advantageous.
A number of different vector technologies and gene delivery methods have been proposed and tested for delivering genes in vivo, including viral vectors and various nucleic acid encapsulation techniques. Alternative viral delivery vehicles for genes include murine retroviruses, recombinant adenoviral vectors, adeno-associated virus, HSV, EBV, HIV vectors, and baculovirus. Nonviral gene delivery methods use cationic or neutral liposomes, direct injection of plasmid DNA, and polymers. Various strategies to enhance efficiency of gene transfer have been tested such as fusogenic peptides in combination with liposomes or polymers to enhance the release of plasmid DNA from endosomes.
Each of the various gene delivery techniques has been found to possess different strengths and weaknesses. Recombinant retroviruses stably integrate into the chromosome but require host DNA synthesis to insert. Adenoviruses can infect non-dividing cells but cause immune reactions leading to the elimination of therapeutically transduced cells. Adeno-associated virus (AAV) is not pathogenic and does not elicit immune responses but new production strategies are required to obtain high AAV titers for preclinical and clinical studies. Wild-type AAVs integrate into chromosome 19, whereas recombinant AAVs are deprived of site- specific integration and may also persist episomally. Herpes Simplex Virus (HSV) vectors can infect non-replicating cells, such as neuronal cells, and has a high payload capacity for foreign DNA but inflict cytotoxic effects. It seems that each delivery system will be developed independently of the others and that each will demonstrate strengths and weaknesses for certain applications. At present, retroviruses are most commonly used in human clinical trials, followed by adenoviruses, cationic liposomes and AAV.
As the challenges of perfecting gene therapy techniques have become apparent, a variety of additional delivery systems have been proposed to circumvent the difficulties observed with standard technologies. For example, cell-based gene delivery using polymer-encapsulated syngeneic or allogeneic cells implanted into a tissue of a patient can be used to secrete therapeutic proteins. This method is being tested in trials for amyotrophic lateral sclerosis using the ciliary neurotrophic factor gene, and may be extended to Factor VIII and IX for hemophilia, interleukin genes, dopamine-secreting cells to treat Parkinson's disease, nerve growth factor for Alzheimer's disease and other diseases. Other techniques under development include, vectors with the Cre-LoxP recombinase system to rid transfected cells of undesirable viral DNA sequences, use of tissue-specific promoters to express a gene in a particular cell type, or use of ligands recognizing cell surface molecules to direct gene vehicles to a particular cell type.
Additional methods that have been proposed for improving the efficacy of gene therapy technologies include designing p53 "gene bombs" that explode into tumor cells, exploiting the HIV-1 virus to engineer vectors for gene transfer, combining viruses with polymers or cationic lipids to improve gene transfer, the attachment of nuclear localization signal peptides to oligonucleotides to direct genes to nuclei, and the development of molecular switch systems allowing genes to be turned on or off at will. Nevertheless, because of the wide range of disease conditions for which gene therapies are required, and the complexities of developing treatments for such diseases, there remains a need for improved techniques for performing gene therapy. The present invention provides methods and compositions for addressing these issues.
DISCLOSURE OF THE INVENTION A method is disclosed for encapsulating DNA and negatively charged drugs into liposomes having a different lipid composition between their inner and outer membrane bilayers. The liposomes are able to reach primary tumors and their metastases after intravenous injection to animals and humans. The method includes micelle formation between DNA with a mixture of cationic lipid and peptide molecules at molar ratios to nearly neutralization ratios in 10-90% ethanol; the cationic peptides specify nuclear localization and have a hydrophobic moiety endowed with membrane fusion to improve entrance across the cell membrane of the complex. These peptides insert with their cationic portion directed toward condensed DNA and their hydrophobic chain buried together with the hydrophobic chains of the lipids in the micelle membrane monolayer. The DNA lipid/peptide micelles are converted into liposomes by mixing with pre-made liposomes or lipids followed by dilution in aqueous solutions and dialysis to remove the ethanol and allow liposome formation and extrusion through membranes to a diameter below 160 nm entrapping and encapsulating DNA with a very high yield. The encapsulated DNA has a high therapeutic efficacy in eradicating a variety of solid human tumors including, but not limited to, breast carcinoma and prostate carcinoma. A plasmid is constructed with DNA carrying anticancer genes including, but not limited to p53, RB, BRCA1, E1A, bcl-2, MDR-1, p21, pl6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, EL- 12, IL-2, IL-4, IL-7, IFN-γ, TNF-α, HSV-tk (in combination with ganciclovir), E. coli cytosine deaminase (in combination with 5-fluorocytosine) and is combined with encapsulated cisplatin or with other similarly systemically delivered antineoplastic drugs to suppress cancer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 illustrates the structure of the cancer targeted liposome complex.
FIG. 2 illustrates the results of plasmid DNA condensation with various agents as well as various formulation of cationic liposomes in affecting the level of expression of the reporter beta-galactosidase gene after transfection of K562 human erythroleukemia cell cultures.
FIG 3 illustrates tumor targeting in SCID mice. FIG 3A shows a SCID mouse with a large and small human breast tumor before and after staining with X-Gal to test the expression of the transferred gene. Both tumors turn dark blue. The intensity of the blue color is proportional to the expression of the beta-galactosidase gene. FIG 3B shows that in the initial staining of the small tumor, the skin and the intestines at the injection area are the first organs to turn blue. FIG 3C is a view of the back of the animal. The two tumors are clearly visible after removal of the skin (top). Dark staining of the small tumor and light blue staining of the large tumor is evident at an initial stage of staining (bottom). FIG 3D is a view of the front side of the animal. The two tumors are clearly visible after removal of the skin. On the figure to the bottom the dark staining of both tumors is evident at a later stage during staining.
FIG 3E shows the front (top) and rear (bottom) higher magnification view of the dark staining of both tumors at a later stage during staining. Staining of the vascular system around the small tumor can also be seen (bottom).
BRIEF DESCRIPTION OF THE TABLES
Table 1 is a list of molecules able to form micelles. Table 2 lists several fusogenic peptides and describes their properties, along with a reference.
Table 3 lists simple Nuclear Localization Signal (NLS) peptides.
Table 4 shows a list of "bipartite" or "split" NLS peptides.
Table 5 lists "nonpositive NLS" peptides lacking clusters of arginines/lysines.
Table 6 lists peptides with nucleolar localization signals (NoLS).
Table 7 lists peptides having karyophilic clusters on non-membrane protein kinases.
Table 8 lists peptide nuclear localization signals on DNA repair proteins. Table 9 lists NLS peptides in transcription factors.
Table 10 lists NLS peptides in other nuclear proteins.
MODES FOR CARRYING OUT THE INVENTION Definitions The practice of the present invention will employ, unless otherwise indicated, conventional techniques of immunology, molecular biology, microbiology, cell biology and recombinant DNA. These methods are described in the following publications. See, e.g., Sambrook, et al. MOLECULAR CLONING: A LABORATORY
MANUAL, 2nd Edition (1989); CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, F.M.
Ausubel, et al. eds., (1987); the series METHODS IN ENZYMOLOGY (Academic Press, ... Inc.); PCR: A PRACTICAL APPROACH, M. MacPherson, et al., IRL Press at Oxford University Press (1991); PCR 2: A PRACTICAL APPROACH, MacPherson et al., eds. (1995); ANTIBODIES, A LABORATORY MANUAL, Harlow and Lane, eds. (1988); and ANIMAL CELL CULTURE, R.I. Freshney, ed. (1987).
As used in the specification and claims, the singular form "a," "an" and "the" include plural references unless the context clearly dictates otherwise. For example, the term "a cell" includes a plurality of cells, including mixtures thereof.
The term "comprising" is intended to mean that the compositions and methods include the recited elements, but not excluding others. "Consisting essentially of when used to define compositions and methods, shall mean excluding other elements of any essential significance to the combination. Thus, a composition consisting essentially of the elements as defined herein would not exclude trace contaminants from the isolation and purification method and pharmaceutically acceptable carriers, such as phosphate buffered saline, preservatives, and the like. "Consisting of shall mean excluding more than trace elements of other ingredients and substantial method steps for administering the compositions of this invention. Embodiments defined by each of these transition terms are within the scope of this invention.
The terms "polynucleotide" and "nucleic acid molecule" are used interchangeably to refer to polymeric forms of nucleotides of any length. The polynucleotides may contain deoxyribonucleotides, ribonucleotides, and/or their analogs. Nucleotides may have any three-dimensional structure, and may perform any function, known or unknown. The term "polynucleotide" includes, for example, single-, double-stranded and triple helical molecules, a gene or gene fragment, exons, introns, mRNA, tRNA, rRNA, ribozymes, cDNA, recombinant polynucleotides, branched polynucleotides, plasmids, vectors, isolated DNA of any sequence, isolated RNA of any sequence, nucleic acid probes, and primers. A nucleic acid molecule may also comprise modified nucleic acid molecules. A "gene" refers to a polynucleotide containing at least one open reading frame that is capable of encoding a particular polypeptide or protein after being transcribed and translated.
A "gene product" refers to the amino acid (e.g., peptide or polypeptide) generated when a gene is transcribed and translated.
The following abbreviations are used herein: DDAB: dimethyldioctadecyl ammonium bromide (same as N,N-distearyl-N,N-dimethylammonium bromide); DODAC: N,N-dioleyl-N,N-dimethylammonium chloride; DODAP: l,2-dioleoyl-3- dimethylammonium propane; DMRIE: N-[l-(2,3-dimyristyloxy)propyl]-N,N- dimethyl-N-(2-hydroxyethyl) ammonium bromide; DMTAP: 1 ,2-dimyristoyl-3- trimethylammonium propane; DOGS: Dioctadecylamidoglycylspermine; DOTAP (same as DOTMA): N-(l-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride; DOSPA: N-(l-(2,3-dioleyloxy)propyl)-N-(2-
(sperminecarboxamido)ethyl)-N,N-dimethyl ammonium trifluoroacetate; DPTAP: 1,2- dipalmitoyl-3-trimethylammonium propane; DSTAP: l,2-disteroyl-3- trimethylammonium propane; DOPE, 1,2-sn-dioleoylphoshatidylethanolamine; DC-Choi, 3β-(N-(N',N'-dimethylaminoethane)carbamoyl)cholesterol. See, Gao et al., Biochem. Biophys. Res. Comm. 77P:280-285 (1991).
As used herein, the term "pharmaceutically acceptable anion" refers to anions of organic and inorganic acids that provide non-toxic salts in pharmaceutical preparations. Examples of such anions include the halides anions, chloride, bromide, and iodide, inorganic anions such as sulfate, phosphate, and nitrate, and organic anions. Organic anions may be derived from simple organic acids, such as acetic acid, propionic acid, glycolic acid, pyruvic acid, oxalic acid, malic acid, malonic acid, succinic acid, maleic, acid, fumaric acid, tartaric acid, citric acid, benzoic acid, cinnamic acid, mandelic acid, methane sulfonic acid, ethane sulfonic acid, p-toluenesulfonic acid, and the like. The preparation of pharmaceutically acceptable salts is described in Berge, et al., J Pharm. Sci. 66:1-19 (1977), incorporated herein by reference. Physiologically acceptable carriers, excipients or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid; low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, arginine or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA: sugar alcohols such as mannitol or sorbitol; salt-forming counter ions such as sodium; and/or nonionic surfactants such as Tween, Pluronics or polyethylene glycol (PEG). PEG molecules also contain a fusogenic peptide with an attached Nuclear Localization Signal (NLS) covalently linked to the end of the PEG molecule. The term "cationic lipid" refers to any of a number of lipid species that carry a net positive charge at physiological pH. Such lipids include, but are not limited to, DDAB, DMRIE, DODAC, DOGS, DOTAP, DOSPA and DC-Choi. Additionally, a number of commercial preparations of cationic lipids are available that can be used in the present invention. These include, for example, LIPOFECTIN (commercially available cationic liposomes comprising DOTMA and DOPE, from GIBCO/BRL, Grand Island, N.Y., USA); LIPOFECTAMLNE (commercially available cationic liposomes comprising DOSPA and DOPE, from GIBCO/BRL); and TRANSFECTAM (commercially available cationic lipids comprising DOGS in ethanol from Promega Corp., Madison, Wis., USA). This invention further provides a number of methods for producing micelles with entrapped therapeutic drugs. The method is particularly useful to produce micelles of drugs or compositions having a net overall negative charge, e.g., DNA, RNA or negatively charged small molecules. For example, the DNA can be comprised within a plasmid vector and encode for a therapeutic protein, e.g., wild- type p53, HSV-tk, p21, Bax, Bad, IL-2, IL-12, GM-CSF, angiostatin, endostatin and oncostatin. In one embodiment, the method requires combining an effective amount of the therapeutic agent with an effective amount of cationic lipids. Cationic lipids useful in the methods of this invention include, but are not limited to, DDAB, dimethyldioctadecyl ammonium bromide; DMRIE: N-[l-(2,3- dimyristyloxy)propyl]-N,N-dimethyl-N-(2-hydroxyethyl) ammonium bromide; DMTAP: l,2-dimyristoyl-3-trimethylammonium propane; DOGS: Dioctadecylamidoglycylspermine; DOTAP (same as DOTMA): N-(l-(2,3- dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride; DPTAP: 1,2- dipalmitoyl-3-trimethylammonium propane; DSTAP: l,2-disteroyl-3- trimethylammonium propane.
In one aspect, a ratio of from about 30 to about 90% of phosphates contained within the negatively charged therapeutic agent are neutralized by positive charges on lipid molecules (negative charges are in excess) to form an electrostatic micelle complex in an effective concentration of ethanol. In one aspect, the ethanol solution is from about 20% to about 80% ethanol. In a further aspect, the ethanol concentration is about 30%. The ethanol/cationic lipid/therapeutic agent complex is then combined with an effective amount of a fusogenic-karyophilic peptide conjugate. In one aspect, an effective amount of the conjugate is a ratio range from about 0.0 to about 0.3 (positive charges on peptide to negative charges on phosphate groups) to neutralize the majority of the remaining negative charges on the phosphate groups of the therapeutic agents thereby leading to an almost complete neutralization of the complex. The optimal conditions give to the complex a slightly negative charge. However, when the positive charges on cationic lipids exceed the negative charges on the DNA, the excess of positive charges are neutralized by DPPG (dipalmitoyl phosphatidyl glycerol) and its derivatives, or by other anionic lipid molecules in the final micelle complex. In an alternative embodiment, the above methods can be modified by addition of DNA condensing agents selected from spermine, spermidine, and magnesium or other divalent metal ions neutralizing a certain percentage (1-20%) of phosphate groups.
In a further embodiment, the cationic lipids are combined with an effective amount of fusogenic lipid DOPE at various molar ratios for example, in a molar ratio of from about 1:1 cationic lipid:DOPE. In an alternative embodiment, the cationic lipids are combined with an effective amount of a fusogenic/NLS peptide conjugate. Examples of fusogenic/NLS peptide conjugates include, but are not limited to (KAWLKAF)3 (SEQ ID NO:l), GLFKAAAKLLKSLWKLLLKA (SEQ ID NO:2), LLLKAFAKLLKSLWKLLLKA (SEQ ID NO:3), as well as all derivatives of the prototype (Hydrophobic3-Karyophilicl-Hydrophobic2- Karyophilicl)2-3 where Hydrophobic is any of the A, I, L, V, P, G, W, F and Karyophilic is any of the K, R, or H, containing a positively-charged residue every 3rd or 4th amino acid, which form alpha helices and direct a net positive charge to the same direction of the helix. Additional examples include but are not limited to GLFKAIAGFIKNGWKGMIDGGGYC (SEQ ID NO:4) from influenza virus hemagglutinin HA-2; YGRKKRRQRRR (SEQ ID NO:5) from TAT of HIV;
MSGTFGGILAGLIGLL(K/R/H)ι-6 (SEQ ID NO:6), derived from the N-terminal region of the S protein of duck hepatitis B virus, but with the addition of one to six positively-charged lysine, arginine or histidine residues, and combinations of these, able to interact directly with the phosphate groups of plasmid or oligonucleotide DNA, compensating for part of the positive charges provided by the cationic lipids. GAAIGLAWIPYFGPAA (SEQ ID NO:7) is derived from the fusogenic peptide of the Ebola virus transmembrane protein; residues 53-70 (C-terminal helix) of apolipoprotein (apo) All peptide; the 23-residue fusogenic N-terminal peptide of HIV-1 transmembrane glycoprotein gp41; the 29-42 -residue fragment from Alzheimer's β-amyloid peptide; the fusion peptide and N-terminal heptad repeat of Sendai virus; the 56-68 helical segment of lecithin cholesterol acyltransferase. Included within these embodiments are shorter versions of these peptides, that are known to induce fusion of unilamellar lipid vesicles or all that are similarly derivatized with the addition of one to six positively-charged lysine, arginine or histidine residues (K R/H)ι-6 able to interact directly with the phosphate groups of plasmid or oligonucleotide DNA, compensating for part of the positive charges provided by the cationic lipids. The fusogenic peptides in the fusogenic/NLS conjugates represent hydrophobic amino acid stretches, and smaller fragments of these peptide sequences, that include all signal peptide sequences used in membrane or secreted proteins that insert into the endoplasmic reticulum. Alternatively, the conjugates represent transmembrane domains and smaller fragments of these peptide sequences.
In one aspect of the invention, the NLS peptide component in fusogenic/NLS peptide conjugates is derived from the fusogenic hydrophobic peptides. However, there is an addition of 5-6 amino acid karyophilic Nuclear
Localization Signals (NLS) derived from a number of known NLS peptides, as well as from searches of the nuclear protein databases, for stretches of five or more karyophilic amino acid stretches in proteins containing at least four positively- charged amino aids flanked by a proline (P) or glycine (G). Examples of NLS peptides are shown in Tables 1-8. The NLS peptide component in fusogenic/NLS peptide conjugates are synthetic peptides containing the above said NLS, but further modified by additional K, R, H residues at the central part of the peptide or with P or G at the N- or C-terminus.
In a further aspect, the fusogenic/NLS peptide conjugates are derived from the said fusogenic hydrophobic peptides but with the addition of a stretch of H4-6 (four to six histidine residues) in the place of NLS. Micelle formation takes place at pH 5-6 where histidyl residues are positively charged but lose their charge at the nearly neutral pH of the biological fluids, thus releasing the plasmid or oligonucleotide DNA from their electrostatic interaction.
The fusogenic peptide/NLS peptide conjugates are linked to each other with a short amino acid stretch representing an endogenous protease cleavage site. In a preferred aspect of the invention, the structure of the preferred prototype fusogenic/NLS peptide conjugate used in this invention is: PKKRRGPSP(L/A/I)ι2- 20 (SEQ ID NO:8), where (L/A/I)12-20 is a stretch of 12-20 hydrophobic amino acids containing A, L, I, Y, W, F and other hydrophobic amino acids.
The micelles made by the above methods are further provided by this invention by conversion into liposomes. An effective amount of liposomes (diameter from about 80 to about 160 nm), or of a lipid solution composed of cholesterol (from about 10% to about 50%), neutral phospholipid such as hydrogenated soy phosphatidylcholine (HSPC) (from about 40% to about 90%), and the derivatized vesicle-forming lipid PEG-DSPE (distearoylphosphatidyl ethanolamine) from about 1-to about 7 mole percent, is added to the micelle solution.
In a specific embodiment, the liposomes are composed of vesicle-forming lipids and between from about 1 to about 7 mole percent of distearoylphosphatidyl ethanolamine (DSPE) derivatized with a polyethyleneglycol. The composition of claim 20, wherein the polyethyleneglycol has a molecular weight is between about 1,000 to 5,000 daltons. Micelles are converted into liposomes with a concomitant decrease of the ethanol concentration which can be accomplished by removal of the ethanol by dialysis of the liposome complexes through permeable membranes or reduced to a diameter of 80-160 nm by extrusion through membranes.
Liposome encapsulated therapeutic agents produced by the above methods are further provided by this invention. Also provided herein is a method for delivering a therapeutic agent such as plasmid DNA or oligonucleotides to a tissue cell in vivo by intravenous, or other type of injection of the micelles or liposomes. This method specifically targets a primary tumor and the metastases by the long circulating time of the micelle or liposome complex because of the exposure of PEG chains on its surface, its small size (80-160 nm) and the decrease in hydrostatic pressure in the solid tumor from the center to its periphery supporting a preferential extravasation through the tumor vasculature to the extracellular space in tumors. A method for delivering plasmid or oligonucleotide DNA across the cell membrane barrier of the tumors using the micelle or liposome complexes described herein is capable because of the presence of the fusogenic peptides in the complex. In particular, a method for delivering plasmid or oligonucleotide DNA to the liver, spleen and bone marrow after intravenous injection of the complexes is provided. Further provided is a method for delivering therapeutic genes to the liver, spleen and bone marrow of cancer and noncancer patients including but not limited to, factor VIII or IX for the therapy of hemophilias, multidrug resistance, cytokine genes for cancer immunotherapy, genes for the alleviation of pain, genes for the alleviation of diabetes and genes that can be introduced to liver, spleen and bone marrow tissue, to produce a secreted form of a therapeutic protein.
The disclosed therapies also provide methods for reducing tumor size by combining the encapsulated plasmid DNA carrying one or more anticancer genes selected from the group consisting of p53, RB, BRCA1, El A, bcl-2, MDR-1, p21, pi 6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN-γ, TNF-α, HSV-tk (in combination with ganciclovir), E. coli cytosine deaminase (in combination with 5-fluorocytosine) with encapsulated antisense oligonucleotides (antisense c-fos, c-myc, K-ras), ribozymes or triplex-forming oligonucleotides directed against genes that control the cell cycle or signaling pathways. These methods can be modified by combining the encapsulated plasmid DNA carrying one or more anticancer genes of with encapsulated or free antineoplastic drugs, consisting of the group of adriamycin, angiostatin, azathioprine, bleomycin, busulfane, camptothecin, carboplatin, carmustine, chlorambucile, chlormethamine, chloroquinoxaline sulfonamide, cisplatin, cyclophosphamide, cycloplatam, cytarabine, dacarbazine, dactinomycin, daunorubicin, didox, doxorubicin, endostatin, enloplatin, estramustine, etoposide, extramustinephosphat, flucytosine, fluorodeoxyuridine, fluorouracil, gallium nitrate, hydroxyurea, idoxuridine, interferons, interleukins, leuprolide, lobaplatin, lomustine, mannomustine, mechlorethamine, mechlorethaminoxide, melphalan, mercaptopurine, methotrexate, mithramycin, mitobronitole, mitomycin, mycophenolic acid, nocodazole, oncostatin, oxaliplatin, paclitaxel, pentamustine, platinum-triamine complex, plicamycin, prednisolone, prednisone, procarbazine, protein kinase C inhibitors, puromycine, semustine, signal transduction inhibitors, spiroplatin, streptozotocine, stromelysin inhibitors, taxol, tegafur, telomerase inhibitors, teniposide, thalidomide, thiamiprine, thioguanine, thiotepa, tiamiprine, tretamine, triaziquone, trifosfamide, tyrosine kinase inhibitors, uramustine, vidarabine, vinblastine, vinca alcaloids, vincristine, vindesine, vorozole, zeniplatin, zeniplatin, and zinostatin.
The following examples are intended to illustrate, but not limit the invention.
Liposome Composition
Liposomes are microscopic vesicles consisting of concentric lipid bilayers. Structurally, liposomes range in size and shape from long tubes to spheres, with dimensions from a few hundred Angstroms to fractions of a millimeter. Vesicle- forming lipids are selected to achieve a specified degree of fluidity or rigidity of the final complex providing the lipid composition of the outer layer. These are neutral (cholesterol) or bipolar and include phospholipids, such as phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylinositol (PI), and sphingomyelin (SM) and other type of bipolar lipids including but not limited to dioleoylphosphatidylethanolamine (DOPE), with a hydrocarbon chain length in the range of 14-22, and saturated or with one or more double C=C bonds. Examples of lipids capable of producing a stable liposome, alone, or in combination with other lipid components are phospholipids, such as hydrogenated soy phosphatidylcholine (HSPC), lecithin, phosphatidylethanolamine, lysolecithin, lysophosphatidylethanolamine, phosphatidylserine, phosphatidylinositol, sphingomyelin, cephalin, cardiolipin, phosphatidic acid, cerebrosides, distearoylphosphatidylethanolamine (DSPE), dioleoylphosphatidylcholine (DOPC), dipalmitoylphosphatidylcholine (DPPC), palmitoyloleoylphosphatidylcholine (POPC), palmitoyloleoylphosphatidylethanolamine (POPE) and dioleoylphosphatidylethanolamine 4-(N-maleimido-methyl)cyclohexane- 1 - carboxylate (DOPE-mal). Additional non-phosphorous containing lipids that can become incorporated into liposomes include stearylamine, dodecylamine, hexadecylamine, isopropyl myristate, triethanolamine-lauryl sulfate, alkyl-aryl sulfate, acetyl palmitate, glycerol ricinoleate, hexadecyl stereate, amphoteric acrylic polymers, polyethyloxylated fatty acid amides, and the cationic lipids mentioned above (DDAB, DODAC, DMRIE, DMTAP, DOGS, DOTAP (DOTMA), DOSPA, DPTAP, DSTAP, DC-Chol). Negatively charged lipids include phosphatidic acid (PA), dipalmitoylphosphatidylglycerol (DPPG), dioleoylphosphatidylglycerol and (DOPG), dicetylphosphate that are able to form vesicles. Preferred lipids for use in the present invention are cholesterol, hydrogenated soy phosphatidylcholine (HSPC) and, the derivatized vesicle-forming lipid PEG-DSPE. Typically, liposomes can be divided into three categories based on their overall size and the nature of the lamellar structure. The three classifications, as developed by the New York Academy Sciences Meeting, "Liposomes and Their Use in Biology and Medicine," December 1977, are multi-lamellar vesicles (MLVs), small uni-lamellar vesicles (SUVs) and large uni-lamellar vesicles (LUVs). SUVs range in diameter from approximately 20 to 50 nm and consist of a single lipid bilayer surrounding an aqueous compartment. Unilamellar vesicles can also be prepared in sizes from about 50 nm to 600 nm in diameter. While unilamellar are single compartmental vesicles of fairly uniform size, MLVs vary greatly in size up to 10,000 nm, or thereabouts, are multi -compartmental in their structure and contain more than one bilayer. LUV liposomes are so named because of their large diameter that ranges from about 600 nm to 30,000 nm; they can contain more than one bilayer. Liposomes may be prepared by a number of methods not all of which produce the three different types of liposomes. For example, ultrasonic dispersion by means of immersing a metal probe directly into a suspension of MLVs is a common way for preparing SUVs. Preparing liposomes of the MLV class usually involves dissolving the lipids in an appropriate organic solvent and then removing the solvent under a gas or air stream. This leaves behind a thin film of dry lipid on the surface of the container. An aqueous solution is then introduced into the container with shaking, in order to free lipid material from the sides of the container. This process disperses the lipid, causing it to form into lipid aggregates or liposomes. Liposomes of the LUV variety may be made by slow hydration of a thin layer of lipid with distilled water or an aqueous solution of some sort. Alternatively, liposomes may be prepared by lyophilization. This process comprises drying a solution of lipids to a film under a stream of nitrogen. This film is then dissolved in a volatile solvent, frozen, and placed on a lyophilization apparatus to remove the solvent. To prepare a pharmaceutical formulation containing a drug, a solution of the drug is added to the lyophilized lipids, whereupon liposomes are formed.
Preparing Cationic Liposome/Cationic Peptide/Nucleic Acid Micelles Cationic lipids, with the exception of sphingosine and some lipids in primitive life forms, do not occur in nature. The present invention uses single-chain amphiphiles which are chloride and bromide salts of the alkyltrimethylammonium surfactants including but not limited to C12 and C16 chains abbreviated DDAB (same as DODAB) or CTAB. The molecular geometry of these molecules determines the critical micelle concentration (ratio between free monomers in solution and molecules in micelles). Lipid exchange between the two states is a highly dynamic process; phospholipids have critical micelle concentration values below IO"8 M and are more stable in liposomes; however, single chain detergents, such as stearylamine, may emerge from the liposome membrane upon dilution or intravenous injection in milliseconds (Lasic, 1997).
Cationic lipids include, but are not limited to, DDAB: dimethyldioctadecyl ammonium bromide (same as N,N-distearyl-N,N-dimethylammonium bromide); DMRIE: N-[l-(2,3-dimyristyloxy)propyl]-N,N-dimethyl-N-(2-hydroxyethyl) ammonium bromide; DODAC: N,N-dioleyl-N,N-dimethylammonium chloride; DMTAP: l,2-dimyristoyl-3-trimethylammonium propane; DODAP: l,2-dioleoyl-3- dimethylammonium propane; DOGS: Dioctadecylamidoglycylspermine; DOTAP (same as DOTMA): N-(l-(2,3-dioleoyloxy)propyl)-N,N,N-trimethylammonium chloride; DOSPA: N-(l-(2,3-dioleyloxy)propyl)-N-(2-(sperminecarboxamido)ethyl)- N,N-dimethyl ammonium trifluoroacetate; DPTAP: 1,2- dipalmitoyl-3- trimethylammonium propane; DSTAP: l,2-disteroyl-3-trimethylammonium propane; DC-Chol, 3 β-(N-(N',N'-dimethylaminoethane)carbamoyl)cholesterol. Lipid-based vectors used in gene transfer have been formulated in one of two ways. In one method, the nucleic acid is introduced into preformed liposomes made of mixtures of cationic lipids and neutral lipids. The complexes thus formed have undefined and complicated structures and the transfection efficiency is severely reduced by the presence of serum. Preformed liposomes are commercially available as LLPOFECTLN and LIPOFECTAMLNE. The second method involves the formation of DNA complexes with mono- or poly-cationic lipids without the presence of a neutral lipid. These complexes are prepared in the presence of ethanol and are not stable in water. Additionally, these complexes are adversely affected by serum (see, Behr, Ace. Chem. Res. 26:274-7 (1993)). An example of a commercially available poly-cationic lipid is TRANSFECTAM. Other efforts to encapsulate DNA in lipid-based formulations have not overcome these problems (see, Szoka et al., Ann. Rev. Biophys. Bioeng. 9:467 (1980); and Deamer, U.S. Patent No. 4,515,736).
The nucleotide polymers can be single-stranded DNA or RNA, or double- stranded DNA or DNA-RNA hybrids. Examples of double-stranded DNA include structural genes, genes including control and termination regions, and self- replicating systems such as plasmid DNA. Particularly preferred nucleic acids are plasmids. Single-stranded nucleic acids include antisense oligonucleotides (complementary to DNA and RNA), ribozymes and triplex-forming oligonucleotides. In order to increase stability, some single-stranded nucleic acids will preferably have some or all of the nucleotide linkages substituted with stable, non-phosphodiester linkages, including, for example, phosphorothioate, phosphorodithioate, phosphoroselenate, methylphosphonate, or O-alkyl phosphotriester linkages.
Encapsulating Cationic Liposome/Cationic Peptide/Nucleic Acid Micelles into Neutral Liposomes
Cationic lipids used with fusogenic peptide/NLS conjugates to provide the inner layer of the particle can be any of a number of substances selected from the group of DDAB, DODAC, DMRIE, DMTAP, DOGS, DOTAP (DOTMA), DOSPA, DPTAP, DSTAP, DC-Chol. The cationic lipid is combined with DOPE. In one group of embodiments, the preferred cationic lipid is DDAB :DOPE 1:1.
Neutral lipids used herein to provide the outer layer of the particles can be any of a number of lipid species that exist either in an uncharged or neutral zwitterionic form at physiological pH. Such lipids are selected from a group consisting of diacylphosphatidylcholine, diacylphosphatidylethanolamine, ceramide, sphingomyelin, cephalin, and cerebrosides. In one group of embodiments, lipids containing saturated, mono-, or di-unsaturated fatty acids with carbon chain lengths in the range of C14 to C22 are preferred. In general, less saturated lipids are more easily sized, particularly when the liposomes must be sized below about 0.16 microns, for purposes of filter sterilization. Consideration of liposome size, rigidity and stability of the liposomes in the final preparation, its shelf life without leakage of the encapsulated DNA, and stability in the bloodstream generally guide the selection of neutral lipids for providing the outer coating of our gene vehicles. Lipids having a variety of acyl chain groups of varying chain length and degree of saturation are available or may be isolated or synthesized by well-known techniques. In another group of embodiments, lipids with carbon chain lengths in the range of C 14 to C22 are used. Preferably, the neutral lipids used in the present invention are hydrogenated soy phosphatidylcholine (HSPC), cholesterol, and PEG- distearoylphosphatidyl ethanolamine (DSPE) or PEG-ceramide.
Methods for preparing liposomes
A variety of methods for preparing various liposome forms have been described in several issued patents, for example, U.S. Patent Nos. 4,229,360; 4,224,179; 4,241,046; 4,737,323; 4,078,052; 4,235,871; 4,501,728; and 4,837,028, as well as in the articles Szoka et al., Ann. Rev. Biophys. Bioeng. 9:467 (1980) and Hope et al., Chem. Phys. Lip. 40:89 (1986). These methods do not produce all three different types of liposomes (MLVs, SUVs, LUVs). For example, ultrasonic dispersion by means of immersing a metal probe directly into a suspension of MLVs is a common way for preparing SUVs.
Preparing liposomes of the MLV class usually involves dissolving the lipids in an appropriate organic solvent and then removing the solvent under a gas or air stream. This leaves behind a thin film of dry lipid on the surface of the container. An aqueous solution is then introduced into the container with shaking, in order to free lipid material from the sides of the container. This process disperses the lipid, causing it to form into lipid aggregates or liposomes. Liposomes of the LUV variety may be made by slow hydration of a thin layer of lipid with distilled water or an aqueous solution of some sort. Alternatively, liposomes may be prepared by lyophilization. This process comprises drying a solution of lipids to a film under a stream of nitrogen. The film is then dissolved in a volatile solvent, frozen, and placed on a lyophilization apparatus to remove the solvent. To prepare a pharmaceutical formulation containing a drug, a solution of the drug is added to the lyophilized lipids, whereupon liposomes are formed. Following liposome preparation, the liposomes may be sized to achieve a desired size range and relatively narrow distribution of liposome sizes. Preferably, the preformed liposomes are sized to a mean diameter of about 80 to 160 nm (the upper size limit for filter sterilization before in vivo administration). Several techniques are available for sizing liposomes to a desired size. Sonicating a liposome suspension either by bath or probe sonication produces a progressive size reduction down to small unilamellar vesicles less than about 0.05 microns (50 nm) in size. Extrusion of liposome through a small-pore polycarbonate is our preferred method for reducing liposome sizes to a relatively well-defined size distribution. The liposomes may be extruded through successively smaller-pore membranes, to achieve a gradual reduction in liposome size.
One way used to coat DNA with lipid is by controlled detergent depletion from a cationic lipid/DNA/detergent complex. This method can give complexes with stability in plasma. Hofland et al. (1996), have prepared such complexes by dialysis of a mixture of DOSPA/DOPE/DNA octylglucoside.
Pharmaceutical compositions comprising the cationic liposome/nucleic acid complexes of the invention are prepared according to standard techniques and further comprise a pharmaceutically acceptable carrier. Generally, normal saline will be employed as the pharmaceutically acceptable carrier.
For in vivo administration, the pharmaceutical compositions are preferably administered parenterally, i.e., intravenously, intraperitoneally, subcutaneously, intrathecally, injection to the spinal cord, intramuscularly, intraarticularly, portal vein injection, or mtratumorally. More preferably, the pharmaceutical compositions are administered intravenously or mtratumorally by a bolus injection. In other methods, the pharmaceutical preparations may be contacted with the target tissue by direct application of the preparation to the tissue. The application may be made by topical "open" or "closed" procedures. The term "topical" means the direct application of the pharmaceutical preparation to a tissue exposed to the environment, such as the skin, to any surface of the body, nasopharynx, external auditory canal, ocular administration and administration to the surface of any body cavities, inhalation to the lung, genital mucosa and the like.
"Open" procedures are those procedures that include incising the skin of a patient and directly visualizing the underlying tissue to which the pharmaceutical preparations are applied. This is generally accomplished by a surgical procedure, such as a thoracotomy to access the lungs, abdominal laparotomy to access abdominal viscera, or other direct surgical approach to the target tissue.
"Closed" procedures are invasive procedures in which the internal target tissues are not directly visualized, but accessed via insertion of instruments through small wounds in the skin. For example, the preparations may be administered to the peritoneum by needle lavage. Likewise, the pharmaceutical preparations may be administered to the meninges or spinal cord by infusion during a lumbar puncture followed by appropriate positioning of the patient as commonly practiced for spinal anesthesia or metrazamide imaging of the spinal cord. Alternatively, the preparations may be administered through endoscopic devices. EXAMPLES Materials and Methods
DDAB, DOPE (dioleoylphosphatidylethanolamine) and most other lipids used here were purchased from Avanti Polar Lipids; PEG-DSPE was from Syngena.
Engineering of plasmid pLF
The pGL3-C (Promega) was cut with Xbal and blunt-end ligated using the Klenow fragment of E. coli DNA polymerase. It was then cut with Hindlll and the 1689-bp fragment, carrying the luciferase gene, was gel-purified. The pGFP-Nl plasmid (Clontech) was cut with Smal and Hindlll and the 4.7 kb fragment, isolated from an agarose gel, was ligated with the luciferase fragment. JM109 E. coli cells were transformed and 20 colonies were selected; about half of them showed the presence of inserts; 8 clones with inserts were cut with BamHI and Xhol to further confirm the presence of the luciferase gene; seven of them were positive. Radiolabeled plasmid pLF was generated by culturing Escherichia coli in
3H-thymidine-5 '-triphosphate or 32P inorganic phosphate (5 mCi) (Dupont/NEN, Boston, Mass.) and purified using standard techniques as described above.
DLS measurements A Coulter N4M light scattering instrument was used, at a 90° angle, set at a run time of 200 sec, using 4 to 25 microsec sample time. The scan of the particle size distribution was obtained in 1 ml sample volume using plastic cuvettes, at 20°C and at 0.01 poise viscosity.
In one aspect, this invention provides a method for entrapping DNA into lipids that enhances the content of plasmid per volume unit, and reduces the toxicity of the cationic lipids used to trap plasmid or oligonucleotide DNA. The DNA becomes hidden in the inner membrane bilayer of the final complex. Furthermore, the gene transfer complex is endowed with long circulation time in body fluids and extravasates preferentially into solid tumors and their metastatic foci and nodules. The extravasation occurs through their vasculature at most sites of the human or animal body after intravenous injection of the gene-carrying vehicles. This occurs because of their small size (100-160 nm), their content in neutral to slightly negatively-charged lipids in their outer membrane bilayers, and their coating with PEG. These gene delivery vehicles are able to cross the cell membrane barrier after they reach the extracellular tumor space because of the presence of fusogenic peptides conjugated with karyophilic peptides. The vehicles assume a certain predefined orientation in the lipid membrane with their positive ends directed toward DNA and their hydrophobic tail buried inside the hydrophobic lipid bilayer. The labile NLS-fusogenic peptide linkage is cleaved after endocytosis and the remaining NLS peptide bound to plasmid DNA aids its nuclear uptake. This occurs especially when non-dividing cells are targeted, such as liver, spleen or bone marrow cells that represent the major sites for extravasation and concentration of these vehicles other than solid tumors.
Organic solvent
A suitable solvent for preparing a micelle from the desired lipid components is ethanol, methanol, or other aliphatic alcohols such as propanol, isopropanol, butanol, tert-butanol, iso-butanol, pentanol and hexanol. Mixtures of two or more solvents may be used in the practice of the invention. It is also to be understood that any solvent that is miscible with an ethanol solution, even in small amounts, can be used to improve micelle formation and its subsequent conversion into liposomes, including chloroform, dichloromethane, diethylether, cyclohexane, cyclopentane, benzene, and toluene.
Cationic lipids
In a further embodiment, the liposome encapsulated DNA described herein further comprises an effective amount of cationic lipids. Cationic lipids have been widely used for gene transfer; a number of clinical trials (34 out of 220 total RAC- approved protocols as of December, 1997) use cationic lipids. Although many cell culture studies have been documented, systemic delivery of genes with cationic lipids in vivo has been very limited. All clinical protocols use subcutaneous, intradermal, intratumoral, and intracranial injection as well as intranasal, intrapleural, or aerosol administration but not IV. delivery, because of the toxicity of the cationic lipids and DOPE (see, Martin and Boulikas, 1998). Liposomes formulated from DOPE and cationic lipids based on diacyltrimethylammonium propane (dioleoyl-, dimyristoyl-, dipalmitoyl-, disteroyl-trimethylammonium propane or DOTAP, DMTAP, DPTAP, DSTAP, respectively) or DDAB were highly toxic when incubated in vitro with phagocytic cells (macrophages and U937 cells), but not towards non-phagocytic T lymphocytes. The rank order of toxicity was DOPE/DDAB > DOPE/DOTAP > DOPE/DMT AP > DOPE/DPTAP > DOPE/DSTAP; and the toxicity was determined from the effect of the cationic liposomes on the synthesis of nitric oxide (NO) and TNF-α produced by activated macrophages (Filion and Phillips, 1997). Another aspect to be considered before I.V. injection is undertaken, is that negatively charged serum proteins can interact and cause inactivation of cationic liposomes (Yang and Huang, 1997). Condensing agents used for plasmid delivery including polylysine, transferrin-polylysine, a fifth-generation poly(amidoamine) (PAMAM) dendrimer, poly(ethyleneimine), and several cationic lipids (DOTAP, DC-Chol/DOPE, DOGS/DOPE, and DOTMA/DOPE), were found to activate the complement system to varying extents. Strong complement activation was seen with long-chain polylysines, the dendrimer, poly(ethyleneimine), and DOGS. Modifying the surface of preformed DNA complexes with polyethyleneglycol (Plank et al., 1996) considerably reduced complement activation. Cationic lipids increase the transfection efficiency by destabilizing the biological membranes, including plasma, endosomal, and lysosomal membranes. Incubation of isolated lysosomes with low concentrations of DOTAP caused a striking increase in free activity of β-galactosidase, and even a release of the enzyme into the medium. This demonstrates that the lysosomal membrane is deeply destabilized by the lipid. The mechanism of destabilization was thought to involve an interaction between cationic liposomes and anionic lipids of the lysosomal membrane, thus allowing a fusion between the lipid bilayers. The process was less pronounced at pH 5 than at pH 7.4, and anionic amphipathic lipids were able to prevent partially this membrane destabilization (Wattiaux et al., 1997). In contrast to DOTAP and DMRIE that were 100% charged at pH 7.4, DC-
CHOL was only about 50% charged as monitored by a pH-sensitive fluorophore. This difference decreases the charge on the external surfaces of the liposomes, and was proposed to promote an easier dissociation of bilayers containing DC-CHOL from the plasmid DNA, and an increase in release of the DNA-lipid complex into the cytosol from the endosomes (Zuidam and Barenholz, 1997).
Although cationic lipids have been used widely for the delivery of genes, very few studies have used systemic I.V. injection of cationic liposome-plasmid complexes. This is because of the toxicity of the lipid component in animal models, not humans. Administration by I.V. injection of two types of cationic lipids of similar structure, DOTMA and DOTAP, shows that the transfection efficiency is determined mainly by the structure of the cationic lipid and the ratio of cationic lipid to DNA; the luciferase and GFP gene expression in different organs was transient, with a peak level between 4 and 24 hr, dropping to less than 1% of the peak level by day 4 (Song et al., 1997).
A number of different organs in vivo can be targeted after liposomal delivery of genes or oligonucleotides. Intravenous injection of cationic liposome-plasmid complexes by tail vein in mice, targeted mainly the lung and to a smaller extent the liver, spleen, heart, kidney and other organs (Zhu et al., 1993). Intraperitoneal injection of a plasmid-liposome complex expressing antisense K-ras RNA in nude mice inoculated i.p. with AsPC-1 pancreatic cancer cells harboring K-ras point mutations and PCR analysis indicated that the injected DNA was delivered to various organs except brain (Aoki et al., 1995).
A number of factors for DOTAP:cholesterol/DNA complex preparation including the DNA:liposome ratio, mild sonication, heating, and extrusion were found to be crucial for improved systemic delivery; maximal gene expression was obtained when a homogeneous population of DNA:liposome complexes between 200 to 450 nm in size were used. Cryo-electron microscopy showed that the DNA was condensed on the interior of invaginated liposomes between two lipid bilayers in these formulations, a factor that was thought to be responsible for the high transfection efficiency in vivo and for the broad tissue distribution (Templeton et al., 1997). Steps to improve liposome-mediated gene delivery to somatic cells include, persistence of the plasmid in blood circulation, port of entry and transport across the cell membrane, release from endosomal compartments into the cytoplasm, nuclear import by docking through the pore complexes of the nuclear envelope, expression driven by the appropriate promoter/enhancer control elements, and persistence of the plasmid in the nucleus for long periods (Boulikas, 1998a).
Plasmid condensation with spermine
In a further embodiment, the liposome encapsulated DNA described herein is condensed with spermine and/or spermidine. DNA can be presented to cells in culture as a complex with polycations such as polylysine, or basic proteins such as protamine, total histones or specific histone fractions, protamine (Boulikas and Martin, 1997). The interaction of plasmid DNA with protamine sulfate, followed by the addition of DOTAP cationic liposomes, offered a better protection of plasmid DNA against enzymatic digestion. The method gave consistently higher gene expression in mice via tail vein injection as compared with DOTAP/DNA complexes. 50 μg of luciferase-plasmid per mouse gave 20 ng luciferase protein per mg extracted tissue protein in the lung, that was detected as early as 1 h after injection, peaked at 6 h and declined thereafter. Intraportal injection of protamine/DOTAP/DNA led to about a 100-fold decrease in gene expression in the lung as compared with I.V. injection. Endothelial cells were the primary locus of lacZ transgene expression (Li and Huang, 1997). Protamine sulfate enhanced plasmid delivery into several different types of cells in vitro, using the monovalent cationic liposomal formulations (DC-Chol and lipofectin). This effect was less pronounced with the multivalent cationic liposome formulation, lipofectamine (Sorgi et al., 1997).
Spermine is found to enhance the transfection efficiency of DNA-cationic liposome complexes in cell culture and in animal studies. This biogenic polyamine at high concentrations caused liposome fusion most likely promoted by the simultaneous interaction of one molecule of spermine (four positively charged amino groups) with the polar head groups of two or more molecules of lipids. At low concentrations (0.03-0.1 mM) it promoted anchorage of the liposome-DNA complex to the surface of cells and enhanced significantly transfection efficiency (Boulikas, unpublished). The polycations polybrene, protamine, DEAE-dextran, and poly-L-lysine significantly increased the efficiency of adenovirus-mediated gene transfer in cell culture. This was thought to act by neutralizing the negative charges presented by membrane glycoproteins that reduce the efficiency of adenovirus-mediated gene transfer (Arcasoy et al., 1997).
Oligonucleotide transfer
In a further embodiment, the liposome encapsulates oligonucleotide DNA. Encapsulation of oligonucleotides into liposomes increased their therapeutic index, prevented degradation in cultured cells, and in human serum and reduced toxicity to cells (Thierry and Dritschilo, 1992; Capaccioli et al., 1993; Lewis et al., 1996). However, most studies have been performed in cell culture, and very few in animals in vivo. There are still an important number of improvements needed before these approaches can move into clinical studies. Zelphati and Szoka (1997), have found that complexes of fluorescently labeled oligonucleotides with DOTAP liposomes, entered the cell using an endocytic pathway mainly involving uncoated vesicles. Oligonucleotides were redistributed from punctate cytoplasmic regions into the nucleus. This process was independent of acidification of the endosomal vesicles. The nuclear uptake of oligonucleotides depended on several factors, such as charge of the particle, where positively charged complexes were required for enhanced nuclear uptake. DOTAP increased over 100 fold the antisense activity of a specific anti-luciferase oligonucleotide. Physicochemical studies of oligonucleotide-liposome complexes of different cationic lipid compositions indicated that either phosphatidylethanolamine or negative charges on other lipids in the cell membrane are required for efficient fusion with cationic liposome-oligonucleotide complexes to promote entry to the cell (Jaaskelainen et al., 1994).
Similar results were reported by Lappalainen et al. (1997). Digoxigenin- labeled oligodeoxynucleotides (ODNs) complexed with the polycationic DOSPA and the monocationic DDAB (with DOPE as a helper lipid) were taken up by CaSki cells in culture by endocytosis. The nuclear membrane was found to pose a barrier against nuclear import of ODNs that accumulated in the perinuclear area. Although DOSP A/DOPE liposomes could deliver ODNs into the cytosol, they were unable to mediate nuclear import of ODNs. On the contrary, oligonucleotide-DD AB/DOPE complexes with a net positive charge were released from vesicles into the cytoplasm. It was determined that DD AB/DOPE mediated nuclear import of the oligonucleotides.
DOPE-heme (ferric protoporphyrin IX) conjugates, inserted in cationic lipid particles with DOTAP, protected oligoribonucleotides from degradation in human serum and increased oligoribonucleotide uptake into 2.2.15 human hepatoma cells. The enhancing effect of heme was evident only at a net negative charge in the particles (Takle et al., 1997). Uptake of liposomes labeled with ] ' ]In and composed of DC-Chol and DOPE was primarily by liver, with some accumulation in spleen and skin and very little in the lung after I.V. tail injection. Preincubation of cationic liposomes with phosphorothioate oligonucleotide induced a dramatic, yet transient, accumulation of the lipid in lung that gradually redistributed to liver. The mechanism of lung uptake involved entrapment of large aggregates of oligonucleotides within pulmonary capillaries at 15 min post-injection via embolism. Labeled oligonucleotide was localized primarily to phagocytic vacuoles of Kupffer cells at 24 h post-injection. Nuclear uptake of oligonucleotides in vivo was not observed (Litzinger et al., 1996).
Polyethylene glycol (PEG)-coated liposomes
In a further embodiment, the liposome encapsulated DNA described herein, further comprise coating of the final complex in step 2 (Fig. 1) with PEG. It is often desirable to conjugate a lipid to a polymer that confers extended half-life, such as polyethylene glycol (PEG). Derivatized lipids that are employed, include PEG- modified DSPE or PEG-ceramide. Addition of PEG components prevents complex aggregation, increases circulation lifetime of particles (liposomes, proteins, other complexes, drugs) and increases the delivery of lipid-nucleic acid complexes to the target tissues. See, Maxfield et al., Polymer 7(5:505-509 (1975); Bailey, F.E. et al., in: Nonionic Surfactants, Schick, M.J., ed., pp. 794-821 (1967); Abuchowski, A. et al, J. Biol. Chem. 252:3582-3586 (1977); Abuchowski, A. et al., Cancer Biochem. Biophys. 7:175-186 (1984); Katre, N.V. et al., Proc. Natl. Acad. Sci. USA 84Λ4&7- 1491 (1987); Goodson, R. et al. Bio Technology 5:343-346 (1990).
Conjugation to PEG is reported to have reduced immunogenicity and toxicity. See, Abuchowski et al., J. Biol. Chem. 252:3578-3581 (1977). The extent of enhancement of blood circulation time of liposomes, by coating with PEG is described in U.S. Patent No. 5,013,556. Typically, the concentration of the PEG- modified phospholipids, or PEG-ceramide in the complex will be about 1-7%. In a particularly preferred embodiment, the PEG-modified lipid is a PEG-DSPE.
Coating the surface of liposomes with inert materials designed to camouflage the liposome from the body's host defense systems was shown to increase remarkably the plasma longevity of liposomes. The biological paradigm for this "surface modified" sub-branch was the erythrocyte, a cell that is coated with a dense layer of carbohydrate groups, and that manages to evade immune system detection and to circulate for several months (before being removed by the same type of cell responsible for removing liposomes).
The first breakthrough came in 1987 when a glycolipid (the brain tissue- derived ganglioside GM1), was identified that, when incorporated within the lipid matrix, allowed liposomes to circulate for many hours in the blood stream (Allen and Chonn, 1987). A second glycolipid, phosphatidylinositol, was also found to impart long plasma residence times to liposomes and, since it was extracted from soybeans, not brain tissue, was believed to be a more pharmaceutically acceptable excipient (Gabizon et al., 1989).
A major advance in the surface-modified sub-branch was the development of polymer-coated liposomes (Allen et al. 1991). Polyethylene glycol (PEG) modification had been used for many years to prolong the half-lives of biological proteins (such as enzymes and growth factors) and to reduce their immunogenicity (e.g. Beauchamp et al., 1983). It was reported in the early 1990s that PEG-coated liposomes circulated for remarkably long times after intravenous administration. Half-lives on the order of 24 h were seen in mice and rats, and over 30 hours in dogs. The term "stealth" was applied to these liposomes because of their ability of evade interception by the immune system. The PEG hydrophilic polymers form dense "conformational clouds" to prevent other macromolecules from interaction with the surface, even at low concentrations of the protecting polymer (Gabizon and Papahadjopoulos, 1988; Papahadjopoulos et al., 1991; reviewed by Torchilin, 1998). The increased hydrophilicity of the liposomes after their coating with the amphipathic PEG5000 leads to a reduction in nonspecific uptake by the reticuloendothelial system.
Whereas the half-life of antimyosin immunoliposomes was 40 min, by coating with PEG, they increased their half-life to 1000 min after intravenous injection to rabbits (Torchilin et al., 1992).
Micelles, surfactants and small unilamellar vesicles
In a further embodiment, the liposome encapsulated DNA described herein, further comprise an initial step of micelle formation between cationic lipids and condensed plasmid or oligonucleotide DNA in ethanol solutions. Micelles are small amphiphilic colloidal particles formed by certain kinds of lipid molecules, detergents or surfactants under defined conditions of concentration, solvent and temperature. They are composed of a single lipid layer. Micelles can have their hydrophilic head groups assembled exposing their hydrophobic tails to the solvent (for example in 30- 60% aqueous ethanol solution) or can reverse their structures exposing their polar heads toward the solvent such as by lowering the concentration of the ethanol to below 10% (reverse micelles). Micelle systems are in thermodynamic equilibrium with the solvent molecules and environment. This results in constant phase changes, especially upon contact with biological materials, such as upon introduction to cell culture, injection to animals, dilution, contact with proteins or other macromolecules. These changes result in rapid micelle disassembly or flocculation. This is in contrast to the much higher stability of liposome bilayers.
Single-chain surfactants are able to form micelles (see Table 1, below). These include the anionic (sodium dodecyl sulfate, cholate or oleate) or cationic (cetyl-trimethylammonium bromide, CTAB) surfactants. CTAB, CTAC, and DOIC micelles yielded larger solubility gaps (lower concentration of colloidally suspended DNA) than corresponding SUV particles containing neutral lipid and CTAB (1:1) (Lasic, 1997). Table 1 : Molecules able to form micelles
There is a critical detergent/phospholipid ratio at which lamellar-to-micellar transition occurs. For example, the vesicle-micelle transition was observed for dodecyl maltoside with large unilamellar liposomes. A striking feature of the solubilization process by dodecyl maltoside was the discovery of a new phase, consisting of a very viscous "gel-like" structure composed of long filamentous thread-like micelles, over 1 to 2 microns in length. A long circulating complex needs to be slightly anionic. Therefore the liposomes used for the conversion of the micelles into liposomes contain bipolar lipids (PC, PE) and 1-30% negatively charged lipids (DPPG). The cationic lipids which are toxic, are hidden in the inner liposome membrane bilayer. Those reaching the solid tumor will exert their toxic effects causing apoptosis. Apoptosis will be caused by the delivery of the toxic drug or anti-neoplastic gene or oligonucleotide to the cancer cell but also by the nuclear localization of the cationic lipids (along with plasmid DNA) to the nucleus. Indeed, a number of studies suggest that plasmid DNA is imported to nuclei; its translocation docks cationic lipid molecules electrostatically attached to the DNA. These cationic lipid molecules exert their toxicity by interfering with the nucleosome and domain structure of the chromatin causing local destabilization. This disturbance or aberrant chromatin reorganization could be exerted at the level of the nuclear matrix where plasmid DNA is attached for transcription, autonomous replication, or integration via recombination.
Surfactants have found wide application in formulations such as emulsions (including microemulsions) and liposomes. The most common way of classifying and ranking the properties of the many different types of surfactants, both natural and synthetic, is by the use of the hydrophile/lipophile balance (HLB). The use of surfactants in drug products, formulations and in emulsions has been reviewed (Rieger, in: Pharmaceutical Dosage Forms, Marcel Dekker, Inc., New York, 1988, p. 285). Nonionic surfactants find wide application in pharmaceutical and cosmetic products and are usable over a wide range of pH values. In general, their HLB values range from 2 to about 18, depending on their structure. Nonionic surfactants include, nonionic esters such as ethylene glycol esters, propylene glycol esters, glyceryl esters, polyglyceryl esters, sorbitan esters, sucrose esters, and ethoxylated esters. Nonionic alkanolamides and ethers, such as fatty alcohol ethoxylates, propoxylated alcohols, and ethoxylated/propoxylated, block polymers are also included in this class. The polyoxyethylene surfactants are the most popular members of the nonionic surfactant class.
Anionic surfactants include carboxylates such as soaps, acyl lactylates, acyl amides of amino acids, esters of sulfuric acid such as alkyl sulfates and ethoxylated alkyl sulfates, sulfonates such as alkyl benzene sulfonates, acyl isethionates, acyl taurates and sulfosuccinates, and phosphates. The most important members of the anionic surfactant class are the alkyl sulfates and the soaps.
Cationic surfactants include quaternary ammonium salts and ethoxylated amines. The quatemary ammonium salts are the most used members of this class. If the surfactant molecule has the ability to carry either a positive or negative charge, the surfactant is classified as amphoteric. Amphoteric surfactants include acrylic acid derivatives, substituted alkylamides, N-alkylbetaines and phosphatides.
Classical micelles may not be effective as gene transfer vehicles, but important intermediates in the formation of liposome complexes encapsulating drugs or nucleic acids. The stability of single chain surfactants-DNA-colloidal systems is lower than SUV particles containing neutral lipid and CTAB (1:1). However, second generation micelles are able to target tumors in vivo. Weissig and co- workers (1998) used the soybean trypsin inhibitor (STI) as a model protein to target tumors. STI was modified with a hydrophobic residue of N-glutaryl-phosphatidyl- ethanolamine (NGPE) and incorporated into both polyethyleneglycol (MW 5000)- distearoyl phosphatidyl ethanolamine (PEG-DSPE) micelles (< 20 nm) and PEG- DSPE-modified long-circulating liposomes (ca. 100 nm). As determined from the protein label by using In attached to soybean trypsin inhibitor via protein-attached diethylene triamine pentaacetic acid, DTP A, PEG-lipid micelles accumulated better than the same protein anchored in long-circulating PEG-liposomes in subcutaneously established Lewis lung carcinoma in mice after tail vein injection.
Loading a liposomal dispersion with an amphiphilic drug may cause a phase transformation into a micellar solution. The transition from high ratios of phospholipid to drug (from 2:1 to 1:1 downwards) were accompanied by the conversion of liposomal dispersions of milky- white appearance (particle size 200 nm) to nearly transparent micelles (particle size below 25 nm). See, Schutze and Muller-Goymann (1998).
Fusogenic peptides
In a further embodiment, the liposome encapsulated DNA described herein further comprises an effective amount of a fusogenic peptide. Fusogenic peptides belong to a class of helical amphipathic peptides characterized by a hydrophobicity gradient along the long helical axis. This hydrophobicity gradient causes the tilted insertion of the peptides in membranes, thus destabilizing the lipid core and, thereby, enhancing membrane fusion (Decout et al., 1999). Hemagglutinin (HA) is a homotrimeric surface glycoprotein of the influenza virus. In infection, it induces membrane fusion between viral and endosomal membranes at low pH. Each monomer consists of the receptor-binding HA1 domain and the membrane-interacting HA2 domain. The NH2-terminal region of the HA2 domain (amino acids 1 to 127), the so-called "fusion peptide," inserts into the target membrane and plays a crucial role in triggering fusion between the viral and endosomal membranes. Based on the substitution of eight amino acids in region 5- 14 with cysteines and spin-labeling electron paramagnetic resonance, it was concluded that the peptide forms an alpha-helix tilted approximately 25 degrees from the horizontal plane of the membrane with a maximum depth of 15 A from the phosphate group (Macosko et al., 1997). Use of fusogenic peptides from influenza virus hemagglutinin HA-2 enhanced greatly the efficiency of transferrin-polylysine- DNA complex uptake by cells. The peptide was linked to polylysine and the complex was delivered by the transferrin receptor-mediated endocytosis (reviewed by Boulikas, 1998a). This peptide has the sequence: GLFEAIAGFI ENGWEGMIDG GGYC (SEQ ID NO:9) and is able to induce the release of the fluorescent dye calcein from liposomes prepared with egg yolk phosphatidylcholine, which was higher at acidic pH. This peptide was also able to increase up to 10- fold the anti-HIV potency of antisense oligonucleotides, at a concentration of 0.1-1 mM, using CEM-SS lymphocytes in culture. This peptide changes conformation at the slightly more acidic environment of the endosome, destabilizing and breaking the endosomal membrane (reviewed by Boulikas, 1998a). The presence of negatively charged lipids in the membrane is important for the manifestation of the fusogenic properties of some peptides, but not of others. Whereas the fusogenic action of a peptide, representing a putative fusion domain of fertilin, a sperm surface protein involved in sperm-egg fusion, was dependent upon the presence of negatively charged lipids, that of the HIV2 peptide was not (Martin and Ruysschaert, 1997).
For example, to analyze the two domains on the fusogenic peptides of influenza virus hemagglutinin HA, HA-chimeras were designed in which the cytoplasmic tail and/or transmembrane domain of HA was replaced with the corresponding domains of the fusogenic glycoprotein F of Sendai virus. Constructs of HA were made in which the cytoplasmic tail was replaced by peptides of human neurofibromin type 1 (NFl) (residues 1441 to 1518) or c-Raf-1, (residues 51 to 131) and were expressed in CV-1 cells by using the vaccinia virus-T7 polymerase transient-expression system. Membrane fusion between CV-1 cells and bound human erythrocytes (RBCs) mediated by parental or chimeric HA proteins showed that, after the pH was lowered, a flow of the aqueous fluorophore calcein from preloaded RBCs into the cytoplasm of the protein-expressing CV-1 cells took place. This indicated that membrane fusion involves both leaflets of the lipid bilayers and leads to formation of an aqueous fusion pore (Schroth-Diaz et al., 1998).
A remarkable discovery was that the TAT protein of HIV is able to cross cell membranes (Green and Loewenstein, 1998) and that a 36-amino acid domain of TAT, when chemically cross-linked to heterologous proteins, conferred the ability to transduce into cells. The 11 -amino acid fusogenic peptide of TAT (YGRKKRRQRRR (SEQ ID NO: 10)) is a nucleolar localization signal (see Boulikas, 1998b).
Another protein of HIV, the glycoprotein gp41, contains fusogenic peptides. Linear peptides derived from the membrane proximal region of the gp41 ectodomain have potential applications as anti-HIV agents and inhibit infectivity by adopting a helical conformation (Judice et al., 1997). The 23 amino acid residue, N-terminal peptide of HIV-1 gp41 has the capacity to destabilize negatively charged large unilamellar vesicles. In the absence of cations, the main structure was a pore- forming alpha-helix, whereas in the presence of Ca2+ the conformation switched to a fusogenic, predominantly extended beta-type structure. The fusion activity of HΙV(ala) (bearing the R22-»A substitution) was reduced by 70%, whereas fusogenicity was completely abolished when a second substitution (V2-»E) was included, arguing that it is not an alpha-helical but an extended structure adopted by the HIV-1 fusion peptide that actively destabilizes cholesterol-containing, electrically neutral membranes (Pereira et al., 1997).
The prion protein (PrP) is a glycoprotein of unknown function normally found at the surface of neurons and of glial cells. It is involved in diseases such as bovine spongiform encephalopathy, and Creutzfeldt- Jakob disease in humans, where PrP is converted into an altered form (termed PrPSc). According to computer modeling calculations, the 120 to 133 and 118 to 135 domains of PrP are tilted lipid- associating peptides inserting in a oblique way into a lipid bilayer and able to interact with liposomes to induce leakage of encapsulated calcein (Pillot et al., 1997b). The C-terminal fragments of the Alzheimer amyloid peptide (amino acids 29-
40 and 29-42) have properties related to those of the fusion peptides of viral proteins inducing fusion of liposomes in vitro. These properties could mediate a direct interaction of the amyloid peptide with cell membranes and account for part of the cytotoxicity of the amyloid peptide. In view of the epidemiologic and biochemical linkages between the pathology of Alzheimer's disease and apolipoprotein E (apoE) polymorphism, examination of the potential interaction between the three common apoE isoforms and the C-terminal fragments of the amyloid peptide showed that only apoE2 and apoE3, not apoE4, are potent inhibitors of the amyloid peptide fusogenic and aggregational properties. The protective effect of apoE against the formation of amyloid aggregates was thought to be mediated by the formation of stable apoE/amyloid peptide complexes (Pillot et al., 1997a; Lins et al., 1999). The fusogenic properties of an amphipathic net-negative peptide (WAE 11), consisting of 11 amino acid residues were strongly promoted when the peptide was anchored to a liposomal membrane. The fusion activity of the peptide appeared to be independent of pH and membrane merging, and the target membranes required a positive charge that was provided by incorporating lysine-coupled phosphatidylethanolamine (PE-K). Whereas the coupled peptide could cause vesicle aggregation via nonspecific electrostatic interaction with PE-K, the free peptide failed to induce aggregation of PE-K vesicles (Pecheur et al., 1997).
A number of studies suggest that stabilization of an alpha-helical secondary structure of the peptide after insertion in lipid bilayers in membranes of cells or liposomes is responsible for the membrane fusion properties of peptides. Zn2+, enhances the fusogenic activity of peptides because it stabilizes the alpha-helical structure. For example, the HEXXH (SEQ ID NO:l 1) domain of the salivary antimicrobial peptide, located in the C-terminal functional domain of histatin-5, a recognized zinc-binding motif is in a helicoidal conformation (Martin et al., 1999; Melino et al, 1999; Curtain et al., 1999).
Fusion peptides have been formulated with DNA plasmids to create peptide- based gene delivery systems. A combination of the YKAKnWK (SEQ ID NO: 12) peptide, used to condense plasmids into 40 to 200 nm nanoparticles, with the GLFEALLELLESLWELLLEA (SEQ ID NO: 13) amphipathic peptide, that is a pH- sensitive lytic agent designed to facilitate release of the plasmid from endosomes enhanced expression systems containing the beta-galactosidase reporter gene (Duguid et al., 1998). See Table 2, below. Table 2. Fusogenic peptides
Fusogenic lipids
DOPE is a fusogenic lipid; elastase cleavage of N-methoxy-succinyl- Ala- Ala-Pro- Val-DOPE (SEQ ID NO: 19) converted this derivative to DOPE (overall positive charge) to deliver an encapsulated fluorescent probe, calcein, into the cell cytoplasm (Pak et al., 1999). An oligodeoxynucleic sequence of 30 bases complementary to a region of beta-endorphin mRNA elicited a concentration- dependent inhibition of beta-endorphin production in cell culture after it was 0 encapsulated within small unilamellar vesicles (50 nm) containing dipalmitoyl-DL- alpha-phosphatidyl-L-serine endowed with fusogenic properties (Fresta et al., 1998).
Nuclear localization signals (NLS)
In a further embodiment, the liposome encapsulated plasmid or 5 oligonucleotide DNA described herein further comprise an effective amount of nuclear localization signal (NLS) peptides. Trafficking of nuclear proteins from the site of their synthesis in the cytoplasm to the sites of function in the nucleus through pore complexes is mediated by NLSs on proteins to be imported into nuclei (Tables 3-10, below). Protein translocation from the cytoplasm to the nucleoplasm involves: (i) the formation of a complex of karyopherin α with NLS-protein; (ii) subsequent binding of karyopherin β; (iii) binding of the complex to FXFG peptide repeats on nucleoporins; (iv) docking of Ran-GDP to nucleoporin and to karyopherin heterodimer by plO; (v) a number of association-dissociation reactions on nucleoporins that dock the import substrate toward the nucleoplasmic side with a concomitant GDP-GTP exchange reaction transforming Ran-GDP into Ran-GTP and catalyzed by karyopherin α; and (vi) dissociation from karyopherin β and release of the karyopherin α/NLS-protein by Ran-GTP to the nucleoplasm.
Karyophilic and acidic clusters were found in most non-membrane serine/threonine protein kinases whose primary structure has been examined (Table 6). These karyophilic clusters might mediate the anchoring of the kinase molecules to transporter proteins for their regulated nuclear import and might constitute the nuclear localization signals. In contrast to protein transcription factors that are exclusively nuclear possessing strong karyophilic peptides composed of at least four arginines, (R), and lysines, (K), within an hexapeptide flanked by proline and glycine helix-breakers, protein kinases often contain one histidine and three K+R residues (Boulikas, 1996). This was proposed to specify a weak NLS structure resulting in the nuclear import of a fraction of the total cytoplasmic kinase molecules, as well as in their weak retention in the different ionic strength nuclear environment. Putative NLS peptides in protein kinases may also contain hydrophobic or bulky aromatic amino acids proposed to further diminish their capacity to act as strong NLS. Most mammalian proteins that participate in DNA repair pathways seem to possess strong karyophilic clusters containing at least four R+K over a stretch of six amino acids (Table 7).
Rules to predict nuclear localization of an unknown protein Several simple rules have been proposed for the prediction of the nuclear localization of a protein of an unknown function from its amino acid sequence: (i) An NLS is defined as four arginines (R) plus lysines (K) within an hexapeptide; the presence of one or more histidines (H) in the tetrad of the karyophilic hexapeptide, often found in protein kinases that have a cytoplasmic and a nuclear function, may specify a weak NLS whose function might be regulated by phosphorylation or may specify proteins that function in both the cytoplasm and the nucleus (Boulikas, 1996);
(ii) The K/R clusters are flanked by the α-helix breakers G and P thus placing the NLS at a helix-turn-helix or end of a α-helix. Negatively-charged amino acids (D, E) are often found at the flank of the NLS and on some occasions may interrupt the positively-charged NLS cluster;
(iii) Bulky amino acids (W, F, Y) are not present within the NLS hexapeptide;
(iv) NLS signals may not be flanked by long stretches of hydrophobic amino acids (e.g. five); a mixture of charged and hydrophobic amino acids serves as a mitochondrial targeting signal;
(v) The higher the number of NLSs, the more readily a molecule is imported to the nucleus (Dworetzky et al., 1988). Even small proteins, for example histones (10-22 kDa), need to be actively imported to increase their import rates compared with the slow rate of diffusion of small molecules through pores; (vi) Signal peptides are stronger determinants than NLSs for protein trafficking. Signal peptides direct proteins to the lumen of the endoplasmic reticulum for their secretion or insertion into cellular membranes (presence of transmembrane domains) (Boulikas, 1994);
(vii) Signals for the mitochondrial import of proteins (a mixture of hydrophobic and karyophilic amino acids) may antagonize nuclear import signals and proteins possessing both type of signals may be translocated to both mitochondria and nuclei;
(viii) Strong association of a protein with large cytoplasmic structures (membrane proteins, intermediate filaments) make such proteins unavailable for import even though they posses NLS-like peptides (Boulikas, 1994);
(ix). Transcription factors and other nuclear proteins posses a great different number of putative NLS stretches. Of the sixteen possible forms of putative NLS structures the most abundant types are the θθxθθ, θθθxθ, θθθθ, and θθxθxθ, where θ is R or K, together accounting for about 70% of all karyophilic clusters on transcription factors (Boulikas, 1994);
(x) A small number of nuclear proteins seem to be void of a typical karyophilic NLS. Either non karyophilic peptides function for their nuclear import, as such molecules possess bipartite NLSs, or these NLS-less proteins depend absolutely for import on their strong complexation in the cytoplasm with a nuclear protein partner able to be imported (Boulikas, 1994). This mechanism may ensure a certain stoichiometric ratio of the two molecules in the nucleus, and might be of physiological significance; and
(xi) A number of proteins may be imported via other mechanisms not dependent on classical NLS.
A number of processes have been found to be regulated by nuclear import including nuclear translocation of the transcription factors NF-κB, rNFIL-6, ISGF3, SRF, c-Fos, GR as well as human cyclins A and Bl, casein kinase II, cAMP- dependent protein kinase II, protein kinase C, ERK1 and ERK2. Failure of cells to import specific proteins into nuclei can lead to carcinogenesis. For example, BRCA1 is mainly localized in the cytoplasm in breast and ovarian cancer cells, whereas in normal cells the protein is nuclear. mRNA is exported through the same route as a complex with nuclear proteins possessing nuclear export signals (NES). The majority of proteins with NES are RNA-binding proteins that bind to and escort RNAs to the cytoplasm. However, other proteins with NES function in the export of proteins; CRM1, that binds to the NES sequence on other proteins and interacts with the nuclear pore complex, is an essential mediator of the NES-dependent nuclear export of proteins in eukaryotic cells. Nuclear localization and export signals (NLS and NES) are found on a number of important molecules, including p53, v-Rel, the transcription factor NF-ATc, the c-Abl nonreceptor tyrosine kinase, and the fragile X syndrome mental retardation gene product. The deregulation of their normal import/export trafficking has important implications for human disease. Both nuclear import and export processes can be manipulated by conjugation of proteins with NLS or NES peptides. During gene therapy, the foreign DNA needs to enter nuclei for its transcription. A pathway is proposed involving the complexation of plasmids and oligonucleotides with nascent nuclear proteins possessing NLSs as a prerequisite for their nuclear import. Covalent linkage of NLS peptides to oligonucleotides and plasmids or formation of complexes of plasmids with proteins possessing multiple NLS peptides was proposed (Boulikas, 1998b) to increase their import rates and the efficiency of gene expression. Cancer cells were predicted to import more efficiently foreign DNA into nuclei, compared with terminally differentiated cells because of their increased rates of proliferation and protein import.
Antineoplastic drugs
In a further embodiment, the liposome encapsulated plasmid or oligonucleotide DNA described herein, further comprises its use for reducing tumor size or restricting its growth with combination with encapsulated or free antineoplastic agents. Antineoplastic agents preferably are: (i) alkylating agents having the bis-(2-chloroethyl)-amine group such as chlormethine, chlorambucile, melphalan, uramustine, mannomustine, extramustinephosphat, mechlorethaminoxide, cyclophosphamide, ifosfamide, or trifosfamide; (ii) alkylating agents having a substituted aziridine group, for example tretamine, thiotepa, triaziquone, or mitomycine; (iii) alkylating agents of the methanesulfonic ester type such as busulfane; (iv) alkylating N-alkyl-N-nitrosourea derivatives, for example carmustine, lomustine, semustine, or streptozotocine; (v) alkylating agents of the mitobronitole, dacarbazine, or procarbazine type; (vi) complexing agents such as cis- platin; (vii) antimetabolites of the folic acid type, for example methotrexate; (viii) purine derivatives such as mercaptopurine, thioguanine, azathioprine, tiamiprine, vidarabine, or puromycine and purine nucleoside phosphorylase inhibitors; (ix) pyrimidine derivatives, for example fluorouracil, floxuridine, tegafur, cytarabine, idoxuridine, flucytosine; (x) antibiotics such as dactinomycin, daunorubicin, doxorubicin, mithramycin, bleomycin or etoposide; (xi) vinca alkaloids; (xii) inhibitors of proteins overexpressed in cancer cells such as telomerase inhibitors, glutathione inhibitors, proteasome inhibitors; (xiii) modulators or inhibitors of signal transduction pathways such as phosphatase inhibitors, protein kinase C inhibitors, casein kinase inhibitors, insulin-like growth factor- 1 receptor inhibitor, ras inhibitors, ras-GAP inhibitor, protein tyrosine phosphatase inhibitors; (xiv) tumor angiogenesis inhibitors such as angiostatin, oncostatin, endostatin, thalidomide; (xv) modulators of the immune response and cytokines such as interferons, interleukins, TNF-alpha; (xvi) modulators of the extracellular matrix such as matrix metalloproteinase inhibitors, stromelysin inhibitors, plasminogen activator inhibitor; (xvii) hormone modulators for hormone-dependent cancers (breast cancer, prostate cancer) such as antiandrogen, estrogens; (xviii) apoptosis regulators; (xix) bFGF inhibitor; (xx) multiple drug resistance gene inhibitor; (xxi) monoclonal antibodies or antibody fragments against antigenes overexpressed in cancer cells (anti-Her2/neu for breast cancer); (xxii) anticancer genes whose expression will cause apoptosis, arrest the cell cycle, induce an immune response against cancer cells, inhibit tumor angiogenesis i.e. formation of blood vessels, tumor suppressor genes (p53, RB, BRCA1, E1A, bcl-2, MDR-1, p21, pl6, bax, bcl-xs, E2F, IGF-I VEGF, angiostatin, oncostatin, endostatin, GM-CSF, IL-12, IL-2, IL-4, IL-7, IFN-γ, and TNF-α); and (xxiii) antisense oligonucleotides (antisense c-fos, c-myc, K-ras). Optionally these drugs are administered in combination with chlormethamine, prednisolone, prednisone, or procarbazine or combined with radiation therapy. Future new anticancer drugs added to the arsenal are expected to be ribozymes, triplex-forming oligonucleotides, gene inactivating oligonucleotides, a number of new genes directed against genes that control the cell proliferation or signaling pathways, and compounds that block signal transduction.
Anti-cancer drugs include: acivicin, aclarubicin, acodazole hydrochloride, acronine, adozelesin, adriamycin, aldesleukin, altretamine, ambomycin, ametantrone acetate, aminoglutethimide, amsacrine, anastrozole, anthramycin, asparaginase, asperlin, azacitidine, azetepa, azotomycin, batimastat, benzodepa, bicalutamide, bisantrene hydrochloride, bisnafide dimesylate, bizelesin, bleomycin sulfate, brequinar sodium, bropirimine, busulfan, cactinomycin, calusterone, caracemide, carbetimer, carboplatin, carmustine, carubicin hydrochloride, carzelesin, cedefingol, chlorambucil, cirolemycin, cisplatin, cladribine, crisnatol mesylate, cyclophosphamide, cytarabine, dacarbazine, dactinomycin, daunorubicin hydrochloride, decitabine, dexorrnaplatin, dezaguanine, dezaguanine mesylate, diaziquone, docetaxel, doxorubicin, doxorubicin hydrochloride, droloxifene, droloxifene citrate, dromostanolone propionate, duazomycin, edatrexate, eflornithine hydrochloride, elsamitrucin, enloplatin, enpromate, epipropidine, epirubicin hydrochloride, erbulozole, esorubicin hydrochloride, estramustine, estramustine phosphate sodium, etanidazole, etoposide, etoposide phosphate, etoprine, fadrozole hydrochloride, fazarabine, fenretinide, floxuridine, fludarabine phosphate, fluorouracil, flurocitabine, fosquidone, fostriecin sodium, gemcitabine, gemcitabine hydrochloride, hydroxyurea, idarubicin hydrochloride, ifosfamide, ilmofosine, interferon alfa-2a, interferon α-2b, interferon α-nl, interferon α-n3, interferon β-i a, interferon γ-i b, iproplatin, irinotecan hydrochloride, lanreotide acetate, letrozole, leuprolide acetate, liarozole hydrochloride, lometrexol sodium, lomustine, losoxantrone hydrochloride, masoprocol, maytansine, mechlorethamine hydrochloride, megestrol acetate, melengestrol acetate, melphalan, menogaril, mercaptopurine, methotrexate, methotrexate sodium, metoprine, meturedepa, mitindomide, mitocarcin, mitocromin, mitogillin, mitomalcin, mitomycin, mitosper, mitotane, mitoxantrone hydrochloride, mycophenolic acid, nocodazole, nogalamycin, ormaplatin, oxisuran, paclitaxel, pegaspargase, peliomycin, pentamustine, peplomycin sulfate, perfosfamide, pipobroman, piposulfan, piroxantrone hydrochloride, plicamycin, plomestane, porfimer sodium, porfiromycin, prednimustine, prednisone, procarbazine hydrochloride, puromycin, puromycin hydrochloride, pyrazofurin, riboprine, rogletimide, safingol, safingol hydrochloride, semustine, simtrazene, sparfosate sodium, sparsomycin, spirogermanium hydrochloride, spiromustine, spiroplatin, streptonigrin, streptozocin, sulofenur, talisomycin, taxol, tecogalan sodium, tegafur, teloxantrone hydrochloride, temoporfm, teniposide, teroxirone, testolactone, thiamiprine, thioguanine, thiotepa, tiazofurin, tirapazamine, topotecan hydrochloride, toremifene citrate, trestolone acetate, triciribine phosphate, trimetrexate, trimetrexate glucuronate, triptorelin, tubulozole hydrochloride, uracil mustard, uredepa, vapreotide, verteporfin, vinblastine sulfate, vincristine sulfate, vindesine, vindesine sulfate, vinepidine sulfate, vinglycinate sulfate, vinleurosine sulfate, vinorelbine tartrate, vinrosidine sulfate, vinzolidine sulfate, vorozole, zeniplatin, zinostatin, zorubicin hydrochloride. Other anti-cancer drugs include: 20-epi-l,25 dihydroxyvitamin D3, 5- ethynyluracil, abiraterone, aclarubicin, acylfulvene, adecypenol, adozelesin, aldesleukin, ALL-TK antagonists, altretamine, ambamustine, amidox, amifostine, aminolevulinic acid, amrubicin, amsacrine, anagrelide, anastrozole, andrographolide, angiogenesis inhibitors, antagonist D, antagonist G, antarelix, anti-dorsalizing morphogenetic protein- 1, antiandrogen, antiestrogen, antineoplaston, antisense oligonucleotides, aphidicolin glycinate, apoptosis gene modulators, apoptosis regulators, apurinic acid, ara-CDP-DL-PTBA, arginine deaminase, asulacrine, atamestane, atrimustine, axinastatin 1, axinastatin 2, axinastatin 3, azasetron, azatoxin, azatyrosine, baccatin III derivatives, balanol, batimastat, BCR/ABL antagonists, benzochlorins, benzoylstaurosporine, beta lactam derivatives, beta- alethine, betaclamycin B, betulinic acid, bFGF inhibitor, bicalutamide, bisantrene, bisaziridinylspermine, bisnafide, bistratene A, bizelesin, breflate, bropirimine, budotitane, buthionine sulfoximine, calcipotriol, calphostin C, camptothecin derivatives, canarypox IL-2, capecitabine, carboxamide-amino-triazole, carboxyamidotriazole, CaRest M3, CARN 700, cartilage derived inhibitor, carzelesin, casein kinase inhibitors (ICOS), castanospermine, cecropin B, cetrorelix, chlorlns, chloroquinoxaline sulfonamide, cicaprost, cis-porphyrin, cladribine, clomifene analogues, clotrimazole, collismycin A, collismycin B, combretastatin A4, combretastatin analogue, conagenin, crambescidin 816, crisnatol, cryptophycin 8, cryptophycin A derivatives, curacin A, cyclopentanthraquinones, cycloplatam, cypemycin, cytarabine ocfosfate, cytolytic factor, cytostatin, dacliximab, decitabine, dehydrodide nin B, deslorelin, dexifosfamide, dexrazoxane, dexverapamil, diaziquone, didemnin B, didox, diethylnorspermine, dihydro-5-azacytidine, dihydrotaxol, 9-dioxamycin, diphenyl spiromustine, docosanol, dolasetron, doxifluridine, droloxifene, dronabinol, duocarmycin SA, ebselen, ecomustine, edelfosine, edrecolomab, eflornithine, elemene, emitefur, epirubicin, epristeride, estramustine analogue, estrogen agonists, estrogen antagonists, etanidazole, etoposide phosphate, exemestane, fadrozole, fazarabine, fenretinide, filgrastim, finasteride, flavopiridol, flezelastine, fluasterone, fludarabine, fluorodaunorunicin hydrochloride, forfenimex, formestane, fostriecin, fotemustine, gadolinium gallium nitrate texaphyrin, galocitabine, ganirelix, gelatinase inhibitors, gemcitabine, glutathione inhibitors, hepsulfam, heregulin, hexamethylene bisacetamide, hypericin, ibandronic acid, idarubicin, idoxifene, idramantone, ilmofosine, ilomastat, imidazoacridones, imiquimod, immunostimulant peptides, insulin-like growth factor- 1 receptor inhibitor, interferon agonists, interferons, interleukins, iobenguane, iododoxorubicin, ipomeanol, 4-, irinotecan, iroplact, irsogladine, isobengazole, isohomohalicondrin B, itasetron, jasplakinolide, kahalalide F, lamellarin-N triacetate, lanreotide, leinamycin, lenograstim, lentinan sulfate, leptolstatin, letrozole, leukemia inhibiting factor, leukocyte alpha interferon, leuprolide+estrogen+progesterone, leuprorelin, levamisole, liarozole, linear polyamine analogue, lipophilic disaccharide peptide, lipophilic platinum compounds, lissoclinamide 7, lobaplatin, lombricine, lometrexol, lonidamine, losoxantrone, lovastatin, loxoribine, lurtotecan, lutetium texaphyrin, lysofylline, lytic peptides, maitansine, mannostatin A, marimastat, masoprocol, maspin, matrilysin inhibitors, matrix metalloproteinase inhibitors, menogaril, merbarone, meterelin, methioninase, metoclopramide, MIF inhibitor, mifepristone, miltefosine, mirimostim, mismatched double stranded RNA, mitoguazone, mitolactol, mitomycin analogues, mitonafide, mitotoxin fibroblast growth factor-saporin, mitoxantrone, mofarotene, molgramostim, monoclonal antibody, human chorionic gonadotrophin, monophosphoryl lipid A+myobacterium cell wall sk, mopidamol, multiple drug resistance gene inhibitor, multiple tumor suppressor 1 -based therapy, mustard anticancer agent, mycaperoxide B, mycobacterial cell wall extract, myriaporone, N- acetyldinaline, N-substituted benzamides, nafarelin, nagrestip, naloxone +pentazocine, napavin, naphte in, nartograstim, nedaplatin, nemorubicin, neridronic acid, neutral endopeptidase, nilutamide, nisamycin, nitric oxide modulators, nitroxide antioxidant, nitrullyn, O6-benzylguanine, octreotide, okicenone, oligonucleotides, onapristone, ondansetron, ondansetron, oracin, oral cytokine inducer, ormaplatin, osaterone, oxaliplatin, oxaunomycin, paclitaxel analogues, paclitaxel derivatives, palauamine, palmitoylrhizoxin, pamidronic acid, panaxytriol, panomifene, parabactin, pazelliptine, pegaspargase, peldesine, pentosan polysulfate sodium, pentostatin, pentrozole, perflubron, perfosfamide, perillyl alcohol, phenazinomycin, phenylacetate, phosphatase inhibitors, picibanil, pilocarpine hydrochloride, pirarubicin, piritrexim, placetin A, placetin B, plasminogen activator inhibitor, platinum complex, platinum compounds, platinum- triamine complex, porfimer sodium, porfiromycin, propyl bis-acridone, prostaglandin J2, proteasome inhibitors, protein A-based immune modulator, protein kinase C inhibitor, protein kinase C inhibitors, microalgal., protein tyrosine phosphatase inhibitors, purine nucleoside phosphorylase inhibitors, purpurins, pyrazoloacridine, pyridoxylated hemoglobin polyoxyethylene conjugate, raf antagonists, raltitrexed, ramosetron, ras farnesyl protein transferase inhibitors, ras inhibitors, ras-GAP inhibitor, retelliptine demethylated, rhenium Re 186 etidronate, rhizoxin, ribozymes, RII retinamide, rogletimide, rohitukine, romurtide, roquinimex, rubiginone Bl, ruboxyl, safingol, saintopin, SarCNU, sarcophytol A, sargramostim, Sdi 1 mimetics, semustine, senescence derived inhibitor 1, sense oligonucleotides, signal transduction inhibitors, signal transduction modulators, single chain antigen binding protein, sizofiran, sobuzoxane, sodium borocaptate, sodium phenylacetate, solverol, somatomedin binding protein, sonermin, sparfosic acid, spicamycin D, spiromustine, splenopentin, spongistatin 1, squalamine, stem cell inhibitor, stem-cell division inhibitors, stipiamide, stromelysin inhibitors, sulfmosine, superactive vasoactive intestinal peptide antagonist, suradista, suramin, swainsonine, synthetic glycosaminoglycans, tallimustine, tamoxifen methiodide, tauromustine, tazarotene, tecogalan sodium, tegafur, tellurapyrylium, telomerase inhibitors, temoporfm, temozolomide, teniposide, tetrachlorodecaoxide, tetrazomine, thaliblastine, thalidomide, thiocoraline, thrombopoietin, thrombopoietin mimetic, thymalfasin, thymopoietin receptor agonist, thymotrinan, thyroid stimulating hormone, tin ethyl etiopurpurin, tirapazamine, titanocene dichloride, topotecan, topsentin, toremifene, totipotent stem cell factor, translation inhibitors, tretinoin, triacetyluridine, triciribine, trimetrexate, triptorelin, tropisetron, turosteride, tyrosine kinase inhibitors, tyrphostins, UBC inhibitors, ubenimex, urogenital sinus-derived growth inhibitory factor, urokinase receptor antagonists, vapreotide, variolin B, velaresol, veramine, verdins, verteporfin, vinorelbine, vinxaltine, vitaxin, vorozole, zanoterone, zeniplatin, zilascorb, zinostatin stimalamer.
pH-sensitive peptide-DNA complexes In a further embodiment of the invention, the genes in plasmid DNA are brought in interaction with fusogenic peptide/NLS conjugates. In a further embodiment the NLS moiety is a stretch of histidyl residues able to assume a net positive charge at a pH of about 5 to 6 and to show a reduction or loose completely this charge at pH above 7. The electrostatic interaction of these positively-charged peptides with the negatively-charged plasmid DNA molecules, established at pH 5-6 is weakened at physiological pH (pH-sensitive peptide-DNA complexes). The first step of the present invention involves complex formation between the plasmid or oligonucleotide DNA with the histidyl/fusogenic peptide conjugate and lipid components in 10-90% ethanol at pH 5.0 to 6.0. The conditions must be where the histidyl residues have a net positive charge and can establish electrostatic interactions with plasmids, oligonucleotides or negatively-charged drugs. At the same time, the presence of the positively-charged lipid molecules promotes formation of micelles. At the second step, micelles are converted into liposomes by dilution with water and mixing with pre-made liposomes or lipids at pH 5-6. This is followed by dialysis against pH 7 and extrusion through membranes, entrapping and encapsulating plasmids or oligonucleotides to with a very high yield. Whereas the composition of peptides and cationic lipids in the first step provides the lipids of the internal bilayer, the type of liposomes or lipids added at step 2 provide the external coating of the final liposome formulation (Figure 1). Examples for the formulations of peptides include: HHHHHSPSL16(SEQ ID NO:623), and HHHHHSPS(LAI)5 (SEQ ID NO:624). These are added at a 1 :0.5:0.5 molar ratio (negative charge on DNA: cationic liposome: histidine peptide). The peptide inserts in an alpha-helical conformation inside the lipid bilayer and not only carries out DNA condensation but also endows membrane fusion properties to the complex to improve entrance across the cell membrane. The type of hydrophobic amino acids (for example, content in aromatic amino acids), in the peptide chain is very important as is the length of the peptide chain in ensuring integrity and rigidity of the complexes. Coating the outer surface of the complexes with polyethyleneglycol, hyaluronic acids and other polymers conjugated to lipids gives the particles long circulation properties in body fluids and the ability to target solid tumors and their metastases after intravenous injection, and also the ability to cross the tumor cell membrane. Protease-sensitive linkages in peptides between the NLS and fusogenic moieties
Conversion of micelles into liposomes
An important issue of the present invention is the conversion of micelles formed between the DNA and the cationic lipids, in the presence of ethanol, into liposomes. This is done by the direct addition of the micelle complex into an aqueous solution of preformed liposomes. The liposomes have an average size of 80-160 nm or vice versa, leading to a solution of a final ethanol concentration below 10%. A formulation suitable for pharmaceutical use and for injection into humans and animals will require that the liposomes are of neutral composition (such as cholesterol, PE, PC) coated with PEG.
However, another important aspect is the research application of the present invention, such as for transfection of cells in culture. The composition of the aqueous solution of liposomes is any type of liposomes containing cationic lipids and suitable therefore for transfection of cells in culture such as DDAB:DOPE 1:1. These liposomes are pre-formed and downsized by sonication or extrusion through membranes to a diameter of 80-160 nm. The ethanolic micelle preparations are then added to the aqueous solution of liposomes with a concomitant dilution of the ethanol solution to below 10%. This step will result in further condensation of DNA or interaction of the negatively-charged phosphate groups on DNA with positively charged groups on lipids. Care must be taken so as only part of the negative charges on DNA are neutralized by lipids in the micelle. The remaining charge neutralization of the DNA is to be provided by the cationic component of the preformed liposomes in the second step.
Regulatory DNA and nuclear matrix-attached DNA In a further embodiment of the present invention, the genes in plasmid DNA are driven by regulatory DNA sequences isolated from nuclear matrix-attached DNA using shotgun selection approaches. The compact structural organization of chromatin and the proper spatial orientation of individual chromosomes within a cell are partially provided by the nuclear matrix. The nuclear matrix is composed of DNA, RNA and proteins and serves as the site of DNA replication, gene transcription, DNA repair, and chromosomal attachment in the nucleus. Diverse sets of DNA sequences have been found associated with nuclear matrices and is referred to as matrix attachment regions or MARs. The MARs serve many functions, acting as activators of gene transcription, silencers of gene expression, insulators of transcriptional activity, nuclear retention signals and origins of DNA replication. Current studies indicate that different subsets of MARs are found in different tissue types and may assist in regulating the specific functions of cells. The presence of this complex assortment of structural and regulatory molecules in the matrix, as well as the in situ localization of DNA replication and transcription complexes to the matrix strongly suggest that the nuclear matrix plays a fundamental, unique role in nuclear processes. The structuring of genomes into domains has a functional significance. The inclusion of specific MAR elements within gene transfer vectors could have utility in many experimental and gene therapy applications. Many gene therapy applications require specific expression of one or more genes in targeted cell types for prolonged time periods. MARs within vectors could enhance transcription of the introduced transgene, prolong the retention of that sequence within the nucleus or insulate expression of that transgene from the expression of a cotransduced gene (reviewed by Boulikas, 1995; Bode et al, 1996). Various biochemical procedures have been used to identify regulatory regions within genes. Traditionally, identification and selection of regulatory DNA sequences depend on tedious procedures such as transcription factor footprinting in vitro or in vivo, or subcloning of smaller fragments from larger genomic DNA sequences upstream of reporter genes. These methods have been used primarily to identify regions proximal to the 5' end of genes. However, in many instances, regulatory regions are found at considerable distances from the proximal 5' end of the gene, and confer cell type- or developmental stage- specificity. For example, studies from the groups of Grosveld and Engel (Lakshmanan et al., 1999) have shown that over 625 kb of genomic sequences surrounding the GATA-3 locus are required for the correct developmental expression of the gene in transgenic mice.
Extensive DNA stretches at distances 5-20 kb upstream of the gene were found to be responsible for the central nervous system-specificity of expression. The region between 20 to 130 kb upstream of the gene harbored regulatory regions for urogenital-specific expression of GATA-3, whereas sequences 90-180 kb downstream of the gene conferred endocardial-specific expression.
The presently disclosed method has the potential of rapidly identifying regulatory control regions. In cells, chromatin loops are formed and different attachment regions are used in different cell types or stages of development to modulate the expression of a gene. The presently disclosed method for isolating regulatory regions based on their attachment to the nuclear matrix can identify regulatory regions irrespective of their distance from the gene. Although the human genome project is expected to be almost complete by the year 2000, information on the location and nature of the vast majority of the estimated 500,000 regulatory regions will not be available.
Example 1 Plasmid DNA condenses with various agents, as well as various formulations of cationic liposomes. The condensation affects the level of expression of the reporter beta-galactosidase gene after transfection of K562 human erythroleukemia cell cultures. Liposome compositions are shown in the Table below and in FIG. 2. All lipids were from Avanti Polar Lipids (700 Industrial Park Drive, Alabaster, AL 35007). The optimal ratio oflipid to DNA was 7 nmoles total lipid/μg DNA. The transfection reagent (10 μg DNA mixed with 70 nmoles total lipid) was transferred to a small culture flask followed by the addition of 10 ml K562 cell culture (about 2 million cells total); mixing of cells with the transfection reagent was at 5-10 min after mixing DNA with liposomes. Cells were assayed for beta-galactosidase activity several times at 1-30 days post-transfection. The transfected cells were maintained in cell culture as normal cell cultures.
Best results were obtained when the cells used for transfection were at low number, not near confluence. In all experiments the transfection material was added directly in the presence of serum and antibiotics without removal of the transfection reagent or washings of the cells. This simplifies the transfection procedure and is suitable for lymphoid and other type of cell cultures that do not attach to the dish, but grow in suspension. All DNA condensing agents were purchased from Sigma. They were suspended at 0.1 mg/ml in water. Plasmid pCMVβ was purchased from Clontech and was purified using the Anaconda kit of Althea Technologies (San Diego, CA). PolyK is polylysine, mw 9,400. PolyR is polyarginine. PolyH is polyhistidine.
To 100 μl plasmid solution (10 μg total plasmid DNA) 20 μl or 50 μl of polyK, polyR, polyH, were added; the volume was adjusted to 250 μl with water followed by addition of about 70 μl liposomes (7 nmoles /μg DNA). After incubation for 10 min to 1 h at 20°C the transfection mixture was brought in contact with the cell culture. The best DNA condensing reagent was polyhistidine compared with the popular polylysine. The best cationic lipid was DC-cholesterol (DC-CHOL: 3β pSf-(N',N'-dimethylaminoethane)carbamoyl]cholesterol). SFV is Semliki Forest virus expressing beta-galactosidase. The results are shown in FIG. 2.
Liposome Molecular weight Composition Preparation
L2 DDAB mw 631 DDAB 4.2 μmoles/ml 15 mg DDAB
DOPE mw 744 DOPE 4.2 μmoles/ml + 0.88 ml 20 mg/ml DOPE
L3 DOGS-NTA mw 1015.4 DOGS-NTA 1 μmole/ml 5 mg DOGS
DOPE 1 μmole/ml 0.185 ml DOPE
L4 DC-Chol (mw 537) DC-Chol 1 μmole/ml 0.106 ml DC-Chol (25
DOPE (mw 744) DOPE 1 μmole/ml mg/ml)
+ 0.185 ml DOPE (20 mg/ml)
L5 DOTAP (mw 698) DOTAP 1.4 μmole/ml 0.5 ml 10 mg/ml DOTAP
DOPE (mw 744) DOPE 1.3 μmole/ml + 0.25 ml DOPE (20 mg/ml)
L6 DODAP (mw 648) DODAP 1.54 μmoles/ml 0.5 ml 10 mg/ml
DOPE 1.3 μmole/ml DODAP=5 mg=7.72 μmoles
+ 0.25 ml DOPE (20 mg/ml)
Example 2
Targeting Genes to Tumors Using Gene Vehicles (Lipogenes).
As shown in FIG. 3, tumor targeting in SCID (severe combined immunodeficient) mice were implanted subcutaneously, at two sites, with human MCF-7 breast cancer cells. The cells were allowed to develop into large, measurable solid tumors at about 30 days post-inoculation. Mice were injected intraperitoneously with 0.2 mg plasmid pCMVβ DNA (size of the plasmid is ~4 kb) per animal carrying the bacterial beta-galactosidase reporter gene. Plasmid DNA (200μg, 2.0 mg/ml, 0.1 ml ) was incubated for 5 min with 200μl neutral liposomes of the composition 40% cholesterol, 20% dioleoylphosphatidylethanolamine(DOPE), 12% palmitoyloleoylphosphatidylcholine (POPC), 10% hydrogenated soy phosphatidylcholine (HSPC), 10% distearoylphosphatidylethanolamine (DSPE), 5% sphingomyelin (SM), and 3% derivatized vesicle-forming lipid M-PEG-DSPE.
At this stage, weak complexation of plasmid DNA with neutral (zwitterionic) liposomes takes place. This ensures homogeneous distribution of plasmid DNA to liposomes at the subsequent step of addition of cationic liposomes. After complexation of plasmid DNA with zwitterionic liposomes, 50 μl of cationic liposomes (DC-Chol 1 μmole/ml:DOPE 1.4 μmole/ml) were added and incubated at room temperature for 10 min. At this stage, a mixed liposome population is present and, most likely, formation of a type of liposome-DNA complexes containing lipids from the zwitterionic and cationic lipids takes place. The material was injected (0.35 ml total volume) to the intraperitoneal cavity of the animal. At 5 days post-injection the animal was sacrificed, the skin was removed and the carcass was incubated into X-gal staining solution for about 30 min at 37°C. The animal was incubated in fixative in X-gal staining for about 30 min (addition of 100 μl concentrated glutaraldehyde to 30 ml X-gal staining solution) and the incubation in staining solution continued. Photos were taken in a time course during the incubation period revealing the preferred organs where beta-galactosidase expression took place.
Because of the tumor vasculature targeting shown in FIG. 3E, the data imply that transfer of the genes of angiostatin, endostatin, or oncostatin to the tumors (whose gene products restrict vascular growth and inhibit blood supply to the tumor) is expected to be a rational approach for cancer treatment. Also, a combination therapy using anticancer lipogenes with encapsulated drugs into tumor targeting liposomes appears as a rational cancer therapy.
It is to be understood that while the invention has been described in conjunction with the above embodiments, that the foregoing description and the following examples are intended to illustrate and not limit the scope of the invention. Other aspects, advantages and modifications within the scope of the invention will be apparent to those skilled in the art to which the invention pertains. Table 3 Simple NLS Table 4 "Bipartite" or "split" NLS
Table 5. "Nonpositive NLS" lacking clusters of arginines/lysines
Table 6. Nucleolar localization signals (NoLS) Table 7. Karyophilic clusters on non-membrane protein kinases
Table 8. Nuclear localization signals on DNA repair proteins
Table 9. NLS in Transcription factors
Table 10. NLS in other nuclear proteins
References
U.S. Patent Documents 4,394,448 July, 1983 Szoka, Jr. et al.
4,598,051 July, 1986 Papahadjopoulos et al. 5,013,556 May, 1991 Woodle et al.
Journal Articles
Allen, T.M. and Chonn, A. (1987) "Large unilamellar liposomes with low uptake into the reticuloendothelial system" FEBSLett. 223:42-46. Allen, T.M. et al. (1991) "Liposomes containing synthetic lipid derivatives of polyethylene glycol show prolonged circulation half-lives in vivo" Biochim. Biophys. Ada 1066:29-36.
Anderson, W.F. (1992) "Human gene therapy" Science 255:808-813. Aoki, K. et al. (1995) "Liposome-mediated in vivo gene transfer of antisense K-ras construct inhibits pancreatic tumor dissemination in the murine peritoneal cavity" Cancer Res. 55:3810-3816. Arcasoy, S.M. et al. (1997) "Polycations increase the efficiency of adenovirus- mediated gene transfer to epithelial and endothelial cells in vitro" Gene Ther. 4:32-38. Beauchamp, CO. et al. (1983) "A new procedure for the synthesis of polyethylene glycol-protein adducts; effects on function, receptor recognition, and clearance of superoxide dismutase, lactoferrin, and alpha 2-macroglobulin"
Anal. Biochem. 131:25-33. Bongartz, J.-P. et al. (1994) "Improved biological activity of antisense oligonucleotides conjugated to a fusogenic peptide" Nucl. Acids Res. 22:4681-4688. Boulikas, T. (1993) "Nuclear localization signals (NLS)" Crit. Rev. Eukar. Gene Expression 5:193-227. Boulikas, T. (1994) "Putative nuclear localization signals (NLS) in protein transcription factors" J. Cell. Biochem. 55:32-58. Boulikas, T. (1996a) "Cancer gene therapy and immunotherapy" Intl. J. Oncol. 9:941-954.
Boulikas, T. (1996b) "Gene therapy to human diseases: ex vivo and in vivo studies"
Intl. J Oncol. 9: 1239- 1251. Boulikas, T. (1996c) "Liposome DNA delivery and uptake by cells" Oncol. Rep. 3:989-995. Boulikas, T. (1996d) "Nuclear import of protein kinases and cyclins" J. Cell. Biochem. 60:61-82. Boulikas, T. (1997a) "Gene therapy of prostate cancer: p53, suicidal genes, and other targets" Anticancer Res. 17: 1471 -1506. Boulikas, T. (1997b) "Nuclear import of DNA repair proteins" Anticancer Res. 77:843-864.
Boulikas, T. (1997c) "Nuclear localization signal peptides for the import of plasmid DNA in gene therapy" Int. J. Oncol. 70:301-309. Boulikas, T. (1998a) "Status of gene therapy in 1997: Molecular mechanisms, disease targets, and clinical applications" Gene Tfier. Mol. Biol. 7:1-172. Boulikas, T. (1998b) "Nucleocytoplasmic trafficking: implications for the nuclear import of plasmid DNA during gene therapy" Gene Ther. Mol. Biol. 7:713- 740.
Boulikas, T. and Martin, F. (1997) "Histones, protamine, and polylysine but not poly(E:K) enhance transfection efficiency" Int. J. Oncol. 70:317-322. Capaccioli, S. et al. (1993) "Cationic lipids improve antisense oligonucleotide uptake and prevent degradation in cultured cells and in human serum" Biochem. Biophys. Res. Comm. 797:818-825.
Creuzenet, C. et al. (1997) "Interaction of alpha s2- and beta-casein signal peptides with DMPC and DMPG liposomes" Peptides 75:463-472. Culver, K.W. (1996) in: Gene Therapy: A primer for physicians, Second Edition.
Mary Ann Liebert, Inc. Publications, NY, pp. 1-198. Curtain, C. et al. (1999) "The interactions of the N-terminal fusogenic peptide of
HIV-1 gρ41 with neutral phospholipids" Eur. Biophys. J. 25:427-436. de la Maza, A. et al. (1998) "Solubilization of phosphatidylcholine liposomes by the amphoteric surfactant dodecyl betaine" Chem. Phys. Lipids 94:71-79. Decout, A. et al. (1999) "Contribution of the hydrophobicity gradient to the secondary structure and activity of fusogenic peptides" Mol. Membr. Biol.
75:237-246. Duguid, J.G. et al. (1998) "A physicochemical approach for predicting the effectiveness of peptide-based gene delivery systems for use in plasmid- based gene therapy" Biophys. J. 74:2802-2814. Filion, M.C. and Phillips, N.C. (1997) "Toxicity and immunomodulatory activity of liposomal vectors formulated with cationic lipids toward immune effector cells" Biochim. Biophys. Ada 1329:345-356. Fresta, M. et al. (1998) "Liposomal delivery of a 30-mer antisense oligodeoxynucleotide to inhibit proopiomelanocortin expression" J. Pharm. Sci. 57:616-625.
Gabizon, A. and Papahadjopoulos, D. (1988) "Liposome formulations with prolonged circulation time in blood and enhanced uptake by tumors" Proc.
Natl. Acad. Sci. USA 55:6949-6953. Gabizon, A. et al. (1989) "Pharmacokinetics and tissue localization of doxorubicin encapsulated in stable liposomes with long circulation times" J. Natl. Cancer
Inst. 57:1484-1488. Ghosh, J.K. and Shai, Y. (1999) "Direct Evidence that the N-Terminal Heptad
Repeat of Sendai Virus Fusion Protein Participates in Membrane Fusion" J.
Mol. Biol. 292:531-546. Green, M. and Loewenstein, P.M. (1988) "Autonomous functional domains of chemically synthesized human immunodeficiency virus tat transactivator protein" Cell 55:1179-1188. Gupta, D. and Kothekar, V. (1997) "500 picosecond molecular dynamics simulation of amphiphilic polypeptide Ac(LKKL)4 NHEt with 1,2 di-mysristoyl-sn- glycero-3-phosphorylcholine (DMPC) molecules" Indian J. Biochem.
Biophys. 34:501-511. Holland, H.E.J. et al. (1996) "Formation of stable cationic lipid/DNA complexes for gene transfer" Proc. Natl. Acad. Sci. USA 95:7305-7309. Jaaskelainen, I. et al. (1994) "Oligonucleotide-cationic liposome interactions. A physicochemical study" Biochim. Biophys. Acta 1195:115-123. Judice, J.K. et al. (1997) "Inhibition of HIV type 1 infectivity by constrained alpha- helical peptides: implications for the viral fusion mechanism" Proc. Natl. Acad. Sci. USA 94: 13426- 13430.
Kono, K. et al. (1993) "Fusion activity of an amphiphilic polypeptide having acidic amino acid residues: generation of fusion activity by alpha-helix formation and charge neutralization" Biochim. Biophys. Acta 1164:81-90. Lambert, G. et al. (1998) "The C-terminal helix of human apolipoprotein All promotes the fusion of unilamellar liposomes and displaces apolipoprotein Al from high-density lipoproteins" Eur. J. Biochem. 253:328-338. Lambert, O. et al. (1998) "A new "gel-like" phase in dodecyl maltoside-lipid mixtures: implications in solubilization and reconstitution studies" Biophys.
J. 74:918-930. Lappalainen, K. et al. (1997) "Intracellular distribution of oligonucleotides delivered by cationic liposomes: light and electron microscopic study" Histochem.
Cytochem. 45:265-274. Lasic, D. (1997) in: Liposomes in Gene Delivery, CRC Press, pp. 1-295. Lee, S. et al. (1992) "Effect of amphipathic peptides with different alpha-helical contents on liposome-fusion" Biochim. Biophys. Acta 1103:157-162.
Lelkes, P.I. and Lazarovici, P. (1988) "Pardaxin induces aggregation but not fusion of phosphatidylserine vesicles" FEBS Lett. 250:131-136. Leonard, A.N. and Cohen, D.E. (1998) "Submicellar bile salts stimulate phosphatidylcholine transfer activity of sterol carrier protein 2" J. Lipid Res. 59:1981-1988.
Lewis, J.G. et al. (1996) "A serum-resistant cytofectin for cellular delivery of antisense oligodeoxynucleotides and plasmid DNA" Proc. Natl. Acad. Sci.
USA 95:3176-3181. Li, S. and Huang, L. (1997) "In vivo gene transfer via intravenous administration of cationic lipid-protamine-DNA (LPD) complexes" Gene Ther. 4:891-900.
Lins, L. et al. (1999) "Molecular determinants of the interaction between the C- terminal domain of Alzheimer's beta-amyloid peptide and apolipoprotein E alpha-helices" J. Neurochem. 75:758-769. Litzinger, D.C. et al. (1996) "Fate of cationic liposomes and their complex with oligonucleotide in vivo" Biochim. Biophys. Acta 1281 : 139- 149.
Lopez, O. et al. (1998) "Direct formation of mixed micelles in the solubilization of phospholipid liposomes by Triton X-100" FEBS Lett. 425:314-318. Lusa, S. et al. (1998) "Direct observation of lipoprotein cholesterol ester degradation in lysosomes" Biochem. J. 552:451-457. Macosko, J.C. et al. (1997) "The membrane topology of the fusion peptide region of influenza hemagglutinin determined by spin-labeling EPR" J. Mol. Biol.
267:1139-1148. Macreadie, I.G. et al. (1997) "Cytotoxicity resulting from addition of HIV-1 Nef N- terminal peptides to yeast and bacterial cells" Biochem. Biophys. Res. Commun. 232:707-711.
Martin, F. and Boulikas, T. (1998) "The challenge of liposomes in gene therapy"
Gene Ther. Mol. Biol. 7:173-214. Martin, I. et al. (1999) "Membrane fusion induced by a short fusogenic peptide is assessed by its insertion and orientation into target bilayers" Biochemistry
55:9337-9347. Martin, I. and Ruysschaert, J.M. (1997) "Comparison of lipid vesicle fusion induced by the putative fusion peptide of fertilin (a protein active in sperm-egg fusion) and the NH2-terminal domain of the HIV2 gp41" FEBS Lett.
405:351-355. Massari, S. and Colonna, R. (1986) "Gramicidin induced aggregation and size increase of phosphatidylcholine vesicles" Chem. Phys. Lipids 59:203-220. Melino, S. et al. (1999) "Zn(2+) ions selectively induce antimicrobial salivary peptide histatin-5 to fuse negatively charged vesicles. Identification and characterization of a zinc-binding motif present in the functional domain"
Biochemistry 38:9626-9633. Midoux, P. and Monsigny, M. (1999) "Efficient gene transfer by histidylated polylysine/pDNA complexes" Bioconjug. Chem. 70:406-411.
Murata, M. et al. (1991) "Modification of the N-terminus of membrane fusion-active peptides blocks the fusion activity" Biochem. Biophys. Res. Commun.
179:1050-1055. Niidome, T. et al. (1997) "Membrane interaction of synthetic peptides related to the putative fusogenic region of PH-30 alpha, a protein in sperm-egg fusion" J. .
Peptide Res. 49:563-569. Pak, C.C. et al. (1999) "Elastase activated liposomal delivery to nucleated cells"
Biochim. Biophys. Acta 7479:111-126. Papahadjopoulos, D. et al. (1991) "Sterically stabilized liposomes: Improvements in pharmacokinetics and antitumor therapeutic efficacy" Proc. Natl. Acad. Sci.
USA 55:11460-11464. Parente, R.A. et al. (1988) "pH-dependent fusion of phosphatidylcholine small vesicles. Induction by a synthetic amphipathic peptide" J. Biol. Chem.
255:4724-4730. Partidos, CD. et al. (1996) "Priming of measles virus-specific CTL responses after immunization with a CTL epitope linked to a fusogenic peptide" Virology
215:107-110. Pecheur, E.I. et al. (1997) "Membrane anchorage brings about fusogenic properties in a short synthetic peptide" Biochemistiγ 55:3773-3781. Peelman, F. et al. (1999) "Characterization of functional residues in the interfacial recognition domain of lecithin cholesterol acyltransferase (LCAT)" Protein
Eng. 12:71-78. Pereira, F.B. et al. (1997) "Permeabilization and fusion of uncharged lipid vesicles induced by the HIV-1 fusion peptide adopting an extended conformation: dose and sequence effects" Biophys. J. 75:1977-1986.
Pillot, T. et al. (1999) "The nonfibrillar amyloid beta-peptide induces apoptotic neuronal cell death: involvement of its C-terminal fusogenic domain" J
Neurochem. 75:1626-1634. Pillot, T. et al. (1997) "Specific modulation of the fusogenic properties of the Alzheimer beta-amyloid peptide by apolipoprotein E isoforms" Eur. J.
Biochem. 245:650-659. Pillot, T. et al. (1997) "The 118-135 peptide of the human prion protein forms amyloid fibrils and induces liposome fusion" J. Mol. Biol. 274:381-393. Plank, C et al. (1996) "Activation of the complement system by synthetic DNA complexes: a potential barrier for intravenous gene delivery" Hum. Gene
Ther. 7:1437-1446. Rodriguez-Crespo, I. et al. (1994) "Prediction of a putative fusion peptide in the S protein of hepatitis B virus" J Gen. Virol. 75:637-639.
Rodriguez-Crespo, I. et al. (1999) "Fusogenic activity of hepadenavirus peptides corresponding to sequences downstream of the putative cleavage site"
Virology 257:133-142. Ross, G. et al. (1996) "Gene therapy in the United States: a five-year status report" Hum. Gene Ther. 7:1781-1790.
Schroeder, F. et al. (1990) "Intermembrane cholesterol transfer: role of sterol carrier proteins and phosphatidylserine" Lipids 25:669-674. Schroth-Diez, B. et al. (1998) "Fusion activity of transmembrane and cytoplasmic domain chimeras of the influenza virus glycoprotein hemagglutinin" J. Virol. 72:133-141.
Schutze, W. and Muller-Goymann, C.C. (1998) "Phase transformation of a liposomal dispersion into a micellar solution induced by drug-loading"
Pharm. Res. 75:538-543. Song, Y.K. et al. (1997) "Characterization of cationic liposome-mediated gene transfer in vivo by intravenous administration" Hum. Gene Ther. 5:1585-
1594. Sorgi, F.L. et al. (1997) "Protamine sulfate enhances lipid-mediated gene transfer"
Gene Ther. 4:961-968. Suenaga, M. et al. (1989) "Basic amphipathic helical peptides induce destabilization and fusion of acidic and neutral liposomes" Biochim. Biophys. Acta 957:143-
150. Takle, G.B. et al. (1997) "Delivery of oligoribonucleotides to human hepatoma cells using cationic lipid particles conjugated to ferric protoporphyrin IX (heme)"
Antisense Nucleic Acid Drug Dev. 7: 177- 185. Templeton, N.S. et al. (1997) "Improved DNA: liposome complexes for increased systemic delivery and gene expression" Nature Biotechnol. 15:647-652. Thierry, A.R. and Dritschilo, A. (1992) "Intracellular availability of unmodified, phosphorothioated and liposomally encapsulated oligodeoxynucleotides for antisense activity" Nucl. Acids Res. 20:5691-5698. Tirosh, O. et al. (1998) "Hydration of polyethylene glycol-grafted liposomes"
Biophys. J. 74:1371-1379. Torchilin, V.P. (1998) "Polymer-coated long-circulating microparticulate pharmaceuticals" J. Microencapsul. 75:1-19. Torchilin, V.P. et al. (1992) "Targeted accumulation of polyethylene glycol-coated immunoliposomes in infarcted rabbit myocardium" FASEB J. 5:2716-2719.
Tournois, H. et al. (1990) "Gramicidin A induced fusion of large unilamellar dioleoylphosphatidylcholine vesicles and its relation to the induction of type
II nonbilayer structures" Biochemistry 29:8297-8307. Ulrich, A.S. et al. (1999) "Ultrastructural characterization of peptide-induced membrane fusion and peptide self-assembly in the lipid bilayer" Biophys. J.
77:829-841. Voneche, V. et al. (1992) "The 19-27 amino acid segment of gp51 adopts an amphiphilic structure and plays a key role in the fusion events induced by bovine leukemia virus" J. Biol. Chem. 257:15193-15197.
Wattiaux, R. et al. (1997) "Cationic lipids destabilize lysosomal membrane in vitro" FEBS Lett. 417: 199-202.
Weissig, V. et al. (1998) "Accumulation of protein-loaded long-circulating micelles and liposomes in subcutaneous Lewis lung carcinoma in mice" Pharm. Res. 75:1552-1556.
Zelphati, O. and Szoka, Jr., F.C. (1997) "Intracellular distribution and mechanism of delivery of oligonucleotides mediated by cationic lipids" Pharm. Res.
75:1367-1372.
Zuidam, N.J. and Barenholz, Y. (1997) "Electrostatic parameters of cationic liposomes commonly used for gene delivery as determined by 4-heptadecyl- 7-hydroxycoumarin" Biochim. Biophys. Acta 1329:211-222.

Claims

ClaimsWhat is claimed is:
1. A method for producing micelles with entrapped therapeutic agents, comprising: a) combining an effective amount of a negatively charged therapeutic agent with an effective amount of a cationic lipid in a ratio where about 30% to about 90% the negatively charged atoms are neutralized by positive charges on lipid molecules to form an electrostatic micelle complex in about 20% to about
80% ethanol; and b) combining the micelle complex of step a) with an effective amount of a fusogenic-karyophilic peptide conjugates in a ratio range of about 0.0 to about 0.3, thereby producing micelles with entrapped therapeutic agents.
2. The method of claim 1 , wherein the negatively charged therapeutic agent is a therapeutic agent selected from the group consisting of a polynucleotide and a negatively charged drug.
3. The method of claim 2, wherein the polynucleotide is a DNA polynucleotide or an RNA polynucleotide.
4. The method of claim 2, wherein the polynucleotide is a DNA polynucleotide.
5. The method of claim 4, wherein the DNA polynucleotide comprises plasmid DNA.
6. The method of claim 1, further comprising combining an effective amount of an anionic lipid in step a).
7. The method of claim 6, wherein the anionic lipid is dipalmitoyl phosphatidyl glycerol (DDPG) or a derivative thereof.
8. The method of claim 4, further comprising combining an effective amount of a DNA condensing agent selected from the group consisting of spermine, spermidine, polylysine, polyarginine, polyhistidine, polyornithine and magnesium or a divalent metal ion.
9. The method of claim 5, wherein the plasmid DNA comprises a sequence encoding p53, HSV-tk, p21, Bax, Bad, IL-2, IL-12, GM-CSF, angiostatin, endostatin and oncostatin.
10. The method of claim 1 , wherein the cationic lipids are selected from the group consisting of 3β-(N-(N',N'-dimethylaminoethane)carbamoyl)cholesterol, dimethyldioctadecyl ammonium bromide (DDAB), N-[l-(2,3- dimyristyloxy)propyl]-N,N-dimethyl-N-(2-hydroxyethyl) ammonium bromide (DMRIE), l,2-dimyristoyl-3-trimethylammonium propane (DMTAP), dioctadecylamidoglycylspermine (DOGS), N-(l -(2,3-dioleoyloxy)propyl)-N,N,N- trimethylammonium chloride (DOTMA), 1,2- dipalmitoyl-3-trimethylammonium propane (DPTAP), l,2-disteroyl-3-trimethylammonium propane (DSTAP).
11. The method of claim 10, wherein the cationic lipids are combined with the fusogenic lipid DOPE in a molar ratio from about 1 : 1 to about 2:1.
12. The method of claim 11, wherein the cationic lipids are combined with the fusogenic lipid DOPE in a molar ratio of 1:1.
13. The method of claim 1 , wherein the fusogenic-karyophilic peptide is an NLS peptide.
14. The method of claim 13, wherein the NLS peptide is a peptide selected from the group consisting of Seq. ID Nos. 20 -622.
15. The method of claim 1 , wherein the fusogenic-karyophilic peptide conjugate is a sole fusogenic peptide.
16. The method of claim 1 , wherein the NLS peptide component of the fusogenic-karyophilic peptide conjugate is an NLS peptide selected from the group consisting of Seq. ID Nos. 20-622.
17. The method of claim 1, wherein the fusogenic/NLS peptide conjugates comprise amino acid sequences selected from the group consisting of
(KAWLKAF)3 (SEQ ID NO:l), GLFKAAAKLLKSLWKLLLKA (SEQ ID NO:2), LLLKAFAKLLKSLWKLLLKA (SEQ ID NO:3) as well as all derivatives of the prototype (Hydrophobic3Karyophilic1Hydrophobic2Karyophilicι) -3 where Hydrophobic is any of the A, I, L, V, P, G, W, F and Karyophilic is any of the K, R, or H, containing a positively-charged residue every 3rd or 4th amino acid, that form alpha helices and direct a net positive charge to the same direction of the helix.
18. The method of claim 1, wherein the fusogenic/NLS peptide conjugate comprise an amino acid sequence selected from the group consisting of GLFKAIAGFIKNGWKGMIDGGGYC (SEQ ID NO:4) from influenza virus hemagglutinin HA-2 and YGRKKRRQRRR (SEQ ID NO:5) from TAT of HIV.
19. The method of claim 1 , wherein the fusogenic/NLS peptide conjugate comprise an amino acid sequence selected from the group consisting of MSGTFGGILAGLIGLL(K/R/H)ι^ (SEQ ID NO:6), derived from the N-terminal region of the S protein of duck hepatitis B virus but with the addition of one to six positively-charged lysine, arginine or histidine residues, and combinations of these, GAAIGLAWIPYFGPAA (SEQ ID NO:7) derived from the fusogenic peptide of the Ebola virus transmembrane protein; residues 53-70 (C-terminal helix) of apoUpoprotein (apo) All peptide, the 23-residue fusogenic N-terminal peptide of HIV-1 transmembrane glycoprotein gp41, the 29-42 -residue fragment from Alzheimer's beta-amyloid peptide, the fusion peptide and N-terminal heptad repeat of Sendai virus, the 56-68 helical segment of lecithin cholesterol acyltransferase.
20. The method of any of claim 13 to 19, wherein the NLS peptide component in fusogenic/NLS peptide conjugates are synthetic peptides containing the above said NLS but further modified by additional K, R, H residues at the central part of the peptide or with P or G at the N- or C-terminus.
21. The method of claim 13 , wherein the fusogenic peptide/NLS peptide conjugates are linked to each other with a short amino acid stretch representing an endogenous protease cleavage site.
22. The method of claim 1, wherein the structure of the preferred prototype fusogenic/NLS peptide conjugate used in this invention is: PKKRRGPSP(L/A/I)ι2-20 (SEQ ID NO:8) where (L/A/I)ι2-20 is a stretch of 12-20 " hydrophobic amino acids containing A, L, I, Y, W, F and other hydrophobic amino acids.
23. The method of claim 1, wherein the fusogenic/NLS peptide conjugates are added to the mixture of DNA/cationic lipid and are incorporated into micelles.
24. The method of claim 1, further comprising combining an effective amount of an encapsulating lipid solution to step b).
25. The method of claim 24, wherein the encapsulating lipid is a lipid comprising cholesterol (40%), dioleoylphosphatidylethanolamine (DOPE) (20%), palmitoyloleoylphosphatidylcholine (POPC) (12%), hydrogenated soy phosphatidylcholine (HSPC) (10%), distearoylphosphatidylethanolamine (DSPE) (10%), sphingomyelin (SM) (5%), and derivatized vesicle-forming lipid M-PEG- DSPE (3%).
26. The method of claim 24, wherein the encapsulating lipid is a liposome.
27. The method of claim 26, wherein the liposomes comprises vesicle- . forming lipids and between about 1 to about 7 mole percent of distearoylphosphatidyl ethanolamine (DSPE) derivatized with an effective amount of polyethyleneglycol.
28. The method of claim 27, wherein the liposomes have a selected average size of about 80 to about 160 nm.
29. The method of claim 27, wherein the polyethyleneglycol has a molecular weight from about 1,000 to about 5,000 daltons.
30. A micelle with an entrapped therapeutic agent produced by the method of claim 1.
31. A liposome encapsulated therapeutic agent produced by the method of claim 24.
32. The method of claim 31 , wherein the therapeutic agent further comprises regulation by a liver, spleen or bone marrow regulatory DNA sequence.
33. The method of claim 32, wherein the regulatory DNA sequence is nuclear matrix DNA isolated from liver, spleen or bone marrow cells.
34. A method for delivering a therapeutic agent in vivo, comprising administration of an effective amount of the micelle of claim 30 to a subject.
35. The method of claim 34, wherein the therapeutic agent further comprises regulation by a tumor-specific regulatory DNA sequence.
36. The method of claim 35, wherein the tumor-specific regulatory sequence is nuclear matrix DNA isolated from specific tumor cells.
37. A method for delivering a therapeutic agent in vivo, comprising administration of an effective amount of the liposome encapsulated agent of claim 31 to the subject.
38. The method of claims 34 or 37, wherein the administration is intravenous administration or by injection.
39. A micelle with an entrapped DNA polynucleotide produced by the method of claim 9.
40. A method for reducing tumor size in a subject comprising administration of an effective amount of the micelle of claim 39 to the subject.
41. The method of claim 40, further comprising administration of an effective amount of a second therapeutic agent, wherein the agent is selected from the group consisting of ganciclovir, 5-fluorocytosine, an antisense oligonucleotides a ribozyme, and a triplex-forming oligonucleotide directed against genes that control the cell cycle or signaling pathways.
42. The method of claim 41 , further comprising administration of an effective amount of a second therapeutic agent, wherein the second therapeutic agent is selected from the group consisting of adriamycin, angiostatin, azathioprine, bleomycin, busulfane, camptothecin, carboplatin, carmustine, chlorambucile, chlormethamine, chloroquinoxaline sulfonamide, cisplatin, cyclophosphamide, cycloplatam, cytarabine, dacarbazine, dactinomycin, daunorubicin, didox, doxorubicin, endostatin, enloplatin, estramustine, etoposide, extramustinephosphat, flucytosine, fluorodeoxyuridine, fluorouracil, gallium nitrate, hydroxyurea, idoxuridine, interferons, interleukins, leuprolide, lobaplatin, lomustine, mannomustine, mechlorethamine, mechlorethaminoxide, melphalan, mercaptopurine, methotrexate, mithramycin, mitobronitole, mitomycin, mycophenolic acid, nocodazole, oncostatin, oxaliplatin, paclitaxel, pentamustine, platinum-triamine complex, plicamycin, prednisolone, prednisone, procarbazine, protein kinase C inhibitors, puromycine, semustine, signal transduction inhibitors, spiroplatin, streptozotocine, stromelysin inhibitors, taxol, tegafur, telomerase inhibitors, teniposide, thalidomide, thiamiprine, thioguanine, thiotepa, tiamiprine, tretamine, triaziquone, trifosfamide, tyrosine kinase inhibitors, uramustine, vidarabine, vinblastine, vinca alcaloids, vincristine, vindesine, vorozole, zeniplatin, zeniplatin, and zinostatin.
EP01942131A 2000-06-09 2001-06-08 Encapsulation of polynucleotides and drugs into targeted liposomes Ceased EP1292284A2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US21092500P 2000-06-09 2000-06-09
US210925P 2000-06-09
PCT/US2001/018657 WO2001093836A2 (en) 2000-06-09 2001-06-08 Encapsulation of polynucleotides and drugs into targeted liposomes

Publications (1)

Publication Number Publication Date
EP1292284A2 true EP1292284A2 (en) 2003-03-19

Family

ID=22784880

Family Applications (1)

Application Number Title Priority Date Filing Date
EP01942131A Ceased EP1292284A2 (en) 2000-06-09 2001-06-08 Encapsulation of polynucleotides and drugs into targeted liposomes

Country Status (8)

Country Link
EP (1) EP1292284A2 (en)
JP (1) JP2003535832A (en)
CN (2) CN1254234C (en)
AU (2) AU2001275423B2 (en)
CA (1) CA2411542A1 (en)
MX (1) MXPA02012198A (en)
TW (1) TWI292324B (en)
WO (1) WO2001093836A2 (en)

Families Citing this family (81)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE60144561D1 (en) * 2000-06-16 2011-06-16 Serodus As N AND / OR C TERMINAL WITH SHORT-LOADED PEPTIDE SEQUENCES MODIFIED PEPTIDES
CA2412513A1 (en) * 2000-06-22 2001-12-27 San Diego State University Foundation Modulators of recombination and methods for producing and using the same
CA2420350C (en) * 2000-08-25 2010-07-13 Aventis Pharmaceuticals Inc. Membrane penetrating peptides and uses thereof
GB0103110D0 (en) 2000-08-25 2001-03-28 Aventis Pharma Inc A membrane penetrating peptide encoded by a nuclear localization sequence from human period 1
AU3652602A (en) * 2000-11-15 2002-05-27 Us Gov Health & Human Serv Sol-fusin: use of gp64-6his to catalyze membrane fusion
SE0101702D0 (en) 2001-05-15 2001-05-15 Ardenia Investments Ltd Novel potentiating compounds
DE60231549D1 (en) 2001-12-03 2009-04-23 Dor Biopharma Inc STABILIZED REVERSE MICRO-COMPOSITIONS AND THEIR USE
US20040052928A1 (en) 2002-09-06 2004-03-18 Ehud Gazit Peptides and methods using same for diagnosing and treating amyloid-associated diseases
US7261876B2 (en) 2002-03-01 2007-08-28 Bracco International Bv Multivalent constructs for therapeutic and diagnostic applications
AU2003278807A1 (en) 2002-03-01 2004-08-13 Bracco International B.V. Kdr and vegf/kdr binding peptides and their use in diagnosis and therapy
US7794693B2 (en) 2002-03-01 2010-09-14 Bracco International B.V. Targeting vector-phospholipid conjugates
US8623822B2 (en) 2002-03-01 2014-01-07 Bracco Suisse Sa KDR and VEGF/KDR binding peptides and their use in diagnosis and therapy
JP2003286198A (en) * 2002-03-29 2003-10-07 Japan Science & Technology Corp Therapeutic medicine using protein hollow nanoparticle expression growth factor, and the like
JP2003286199A (en) * 2002-03-29 2003-10-07 Japan Science & Technology Corp Therapeutic medicine for hepatic disease using protein hollow nanoparticle
CA2486007C (en) * 2002-05-15 2011-11-22 California Pacific Medical Center Delivery of nucleic acid-like compounds
EP1530465B2 (en) 2002-06-26 2015-12-16 MediGene AG Method of producing a cationic liposomal preparation comprising a lipophilic compound
DK1519714T3 (en) 2002-06-28 2011-01-31 Protiva Biotherapeutics Inc Method and apparatus for preparing liposomes
US20050232984A1 (en) * 2002-08-23 2005-10-20 Heinrich Haas Non-vesicular cationic lipid formulations
US7491699B2 (en) 2002-12-09 2009-02-17 Ramot At Tel Aviv University Ltd. Peptide nanostructures and methods of generating and using the same
ATE426575T1 (en) 2003-01-07 2009-04-15 Univ Ramot PEPTIDE ANOSTRUCTURES CONTAINING FOREIGN MATERIAL AND METHOD FOR PRODUCING THE SAME
WO2004082626A2 (en) * 2003-03-18 2004-09-30 Ethicon, Inc. Aromatase inhibitor diagnosis and therapy
CA2530927A1 (en) 2003-06-30 2005-01-06 Tel Aviv University Future Technology Development L.P. Peptides antibodies directed thereagainst and methods using same for diagnosing and treating amyloid-associated diseases
WO2005031362A2 (en) 2003-10-02 2005-04-07 Ramot At Tel Aviv University Ltd. Novel antibacterial agents and methods of identifying and utilizing same
EP1793816B1 (en) 2004-08-19 2012-01-04 Tel Aviv University Future Technology Development L.P. Compositions for treating amyloid associated diseases
JP4810825B2 (en) * 2004-12-27 2011-11-09 東洋紡績株式会社 Lipase activity measuring method and measuring reagent
US20070014841A1 (en) * 2005-02-08 2007-01-18 Denis Martin Pharmaceutical compositions
JP5067733B2 (en) * 2005-03-09 2012-11-07 国立大学法人北海道大学 Lipid membrane structure capable of delivering target substance into mitochondria
EP1867726A4 (en) * 2005-03-24 2008-09-24 Univ Hokkaido Nat Univ Corp LIPOSOME CAPABLE OF RELEASING EFFICIENTLY A SUBSTANCE GIVEN IN THE CORE
EP1973928A2 (en) 2005-10-11 2008-10-01 Ramot at Tel-Aviv University Ltd. Self-assembled fmoc-ff hydrogels
CN100376680C (en) * 2005-11-01 2008-03-26 暨南大学 Double target effect gene chimeric recombinant and its construction method and application
EP1790657A1 (en) * 2005-11-24 2007-05-30 Technische Universität München pH-switchable transmembrane peptides as stimulators of membrane fusion
GR20060100144A (en) * 2006-03-03 2007-10-17 Cancer treatment using oxaliplatin encapsulated into liposomes and co-encapsulation into the liposome particle of more than one pharmaceutical preparations, or genes
US20080051380A1 (en) 2006-08-25 2008-02-28 Auerbach Alan H Methods and compositions for treating cancer
KR101129509B1 (en) 2006-10-03 2012-04-13 알닐람 파마슈티칼스 인코포레이티드 Lipid containing formulations
CN101610759A (en) 2006-11-07 2009-12-23 美国政府卫生与公共服务部 Self-assembled nanoparticles composed of transmembrane peptides and their application for specific intratumoral delivery of anticancer drugs
EP2134365B1 (en) * 2007-03-21 2019-03-13 Effat Emamian Compositions and methods for inhibiting tumor cell growth
EP2170267A4 (en) * 2007-06-28 2011-04-27 Agency Science Tech & Res CATIONIC PEPTIDE FOR RELEASING AN AGENT IN A CELL
JP2009203174A (en) * 2008-02-26 2009-09-10 Hokkaido Univ Iontophoresis composition comprising protein-liposome complex
PL2279254T3 (en) 2008-04-15 2017-11-30 Protiva Biotherapeutics Inc. Novel lipid formulations for nucleic acid delivery
WO2010149785A1 (en) * 2009-06-26 2010-12-29 Universiteit Gent Cationic liposomes for the delivery of high molecular weight compounds
US8283333B2 (en) 2009-07-01 2012-10-09 Protiva Biotherapeutics, Inc. Lipid formulations for nucleic acid delivery
CN102038640B (en) * 2009-10-26 2013-11-13 石药集团中奇制药技术（石家庄）有限公司 Liposome medicament containing cholesterol PEG modifier and preparation method thereof
US9006417B2 (en) 2010-06-30 2015-04-14 Protiva Biotherapeutics, Inc. Non-liposomal systems for nucleic acid delivery
DK2590626T3 (en) 2010-07-06 2016-01-25 Glaxosmithkline Biolog Sa Liposomes with lipids having a favorable pKa of RNA for bringing
US9801897B2 (en) 2010-07-06 2017-10-31 Glaxosmithkline Biologicals Sa Delivery of RNA to trigger multiple immune pathways
SI2591114T1 (en) 2010-07-06 2016-10-28 Glaxosmithkline Biologicals S.A. Immunisation of large mammals with low doses of rna
DK4066856T3 (en) 2010-08-31 2022-12-19 Glaxosmithkline Biologicals Sa Pegylated liposomes for delivery of immunogen-encoding RNA
US20140030292A1 (en) 2010-10-11 2014-01-30 Novartis Ag Antigen delivery platforms
JP5911503B2 (en) 2010-11-15 2016-04-27 ラモット・アット・テル・アビブ・ユニバーシテイ・リミテッドＲａｍｏｔ Ａｔ Ｔｅｌ Ａｖｉｖ Ｕｎｉｖｅｒｓｉｔｙ Ｌｔｄ． Dipeptide analogs for treating amyloid fibril formation-related conditions
US9303063B2 (en) 2011-03-18 2016-04-05 Duke University Peptide compounds for suppressing inflammation
US9018169B2 (en) * 2011-03-18 2015-04-28 Duke University Peptides for suppressing inflammation
US11896636B2 (en) 2011-07-06 2024-02-13 Glaxosmithkline Biologicals Sa Immunogenic combination compositions and uses thereof
EP2750707B1 (en) 2011-08-31 2018-10-24 GlaxoSmithKline Biologicals SA Pegylated liposomes for delivery of immunogen-encoding rna
CN104271590B (en) * 2012-01-24 2018-06-05 Inter-K私人有限公司 For the peptide agent of cancer treatment
US10100331B2 (en) 2012-10-29 2018-10-16 Agency For Science, Technology And Research Reagent for gene-drug therapeutics
CN103211762B (en) * 2013-04-11 2015-01-14 同济大学 Novel diagnosis and treatment integrated hybridization micelle and preparation method thereof
EP4501318A2 (en) 2014-04-23 2025-02-05 ModernaTX, Inc. Nucleic acid vaccines
BR112017006057B1 (en) * 2014-09-26 2023-11-21 Universidade Estadual Paulista Júlio De Mesquita Filho - Unesp Pharmaceutical composition based on prostaglandin J2 incorporated into micellar systems based on poloxamers to enhance analgesic and anti-inflammatory activities
MA45481A (en) 2015-06-10 2018-04-18 Univ Texas USE OF EXOSOMES FOR THE TREATMENT OF DISEASES
MX2018004918A (en) * 2015-10-22 2019-04-01 Modernatx Inc Herpes simplex virus vaccine.
JP7080826B2 (en) * 2016-05-16 2022-06-06 ザ ボード オブ リージェンツ オブ ザ ユニバーシティー オブ テキサス システム Cationic sulfonamide aminolipids and amphoteric zwitterionic aminolipids
EP3490560B1 (en) 2016-07-29 2025-01-22 Janssen Pharmaceutica, N.V. Niraparib for use in a method of treating prostate cancer
MA46584A (en) 2016-10-21 2019-08-28 Modernatx Inc HUMAN CYTOMEGALOVIRUS VACCINE
US11752206B2 (en) 2017-03-15 2023-09-12 Modernatx, Inc. Herpes simplex virus vaccine
CN118374452A (en) 2017-08-25 2024-07-23 隆萨销售股份公司 Preparation of therapeutic exosomes using membrane proteins
MX2020006672A (en) 2017-12-28 2020-08-31 Codiak Biosciences Inc EXOSOMES FOR IMMUNO-ONCOLOGY AND ANTI-INFLAMMATORY THERAPY.
KR102617947B1 (en) * 2017-12-29 2023-12-27 쑤저우 리보 라이프 사이언스 컴퍼니, 리미티드 Conjugates and their preparation and uses
WO2020190750A1 (en) 2019-03-15 2020-09-24 Modernatx, Inc. Hiv rna vaccines
KR102101179B1 (en) * 2019-09-20 2020-05-15 건양대학교 산학협력단 Manufacturing Method of Nanocomplex for targeted theraphy in breast cancer stem cell(BCSC)
KR102164218B1 (en) * 2019-09-24 2020-10-12 코스맥스 주식회사 Multilayer cationic liposome for enhancing the skin penetration and preparation method thereof
JPWO2022045009A1 (en) * 2020-08-24 2022-03-03
US11406703B2 (en) 2020-08-25 2022-08-09 Modernatx, Inc. Human cytomegalovirus vaccine
CN117098541A (en) 2020-11-25 2023-11-21 阿卡格拉医药公司 Lipid nanoparticles for delivery of nucleic acids and related methods of use
CN114762679B (en) * 2021-01-13 2023-04-07 上海交通大学医学院 A kind of nanocomposite and its preparation method and application
CN113406957B (en) * 2021-05-19 2022-07-08 成都理工大学 Mobile robot autonomous navigation method based on immune deep reinforcement learning
CN113546180A (en) * 2021-05-25 2021-10-26 重庆医科大学 A kind of gene delivery vector with myocardial targeting and preparation method thereof
US20240336938A1 (en) * 2021-07-19 2024-10-10 Wuhan University Compositions and methods for effective delivery of polynucleotides to cells
KR20230046874A (en) * 2021-09-30 2023-04-06 (주)케어젠 Peptide Having Anti-Aging Activity and Uses Thereof
EP4230638A1 (en) * 2022-02-16 2023-08-23 Lipotrue, S.L. Peptides and compositions for use in cosmetics
CN114632062A (en) * 2022-03-21 2022-06-17 南京大学 Neutral liposome for delivering nucleic acid medicament and preparation method and application thereof
CN119562806A (en) 2022-05-25 2025-03-04 阿卡格拉医药公司 Lipid nanoparticles for delivery of nucleic acids and methods of use thereof

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5635487A (en) * 1994-12-29 1997-06-03 Wolff; Jon A. Amphipathic, micellar delivery systems for biologically active polyions
US6120794A (en) * 1995-09-26 2000-09-19 University Of Pittsburgh Emulsion and micellar formulations for the delivery of biologically active substances to cells
FR2754272B1 (en) * 1996-10-08 1998-11-13 Rhone Poulenc Rorer Sa PROCESS FOR THE PREPARATION OF COMPOSITIONS FOR TRANSFERRING NUCLEIC ACIDS
BR9813548A (en) * 1997-12-12 2000-10-10 Samyang Corp Biodegradable mixed polymeric micelles for gene distribution

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO0193836A2 *

Also Published As

Publication number Publication date
AU2001275423B2 (en) 2007-01-11
CN1444472A (en) 2003-09-24
AU7542301A (en) 2001-12-17
CA2411542A1 (en) 2001-12-13
MXPA02012198A (en) 2004-08-19
CN1981873A (en) 2007-06-20
JP2003535832A (en) 2003-12-02
WO2001093836A3 (en) 2002-10-03
TWI292324B (en) 2008-01-11
CN1254234C (en) 2006-05-03
WO2001093836A2 (en) 2001-12-13

Similar Documents

Publication Publication Date Title
AU2001275423B2 (en) Encapsulation of polynucleotides and drugs into targeted liposomes
US9278067B2 (en) Encapsulation of plasmid DNA (lipogenes™) and therapeutic agents with nuclear localization signal/fusogenic peptide conjugates into targeted liposome complexes
AU2001275423A1 (en) Encapsulation of polynucleotides and drugs into targeted liposomes
Magar et al. Liposome-based delivery of biological drugs
Guevara et al. Advances in lipid nanoparticles for mRNA-based cancer immunotherapy
Moss et al. Lipid nanoparticles for delivery of therapeutic RNA oligonucleotides
Yang et al. Recent advances in liposome formulations for breast cancer therapeutics
Mahato et al. Pharmaceutical perspectives of nonviral gene therapy
Ferreira et al. pH-sensitive liposomes for drug delivery in cancer treatment
Li et al. Nonviral gene therapy
Faneca et al. Evaluation of lipid-based reagents to mediate intracellular gene delivery
AU710170B2 (en) Cationic virosomes as transfer system for genetic material
JP2011500671A (en) Low density lipoprotein-like (LDL-like) cationic nanoparticles for nucleic acid gene transfer, method for producing the same, and method for transferring nucleic acid gene using the same
Uddin Cationic lipids used in non-viral gene delivery systems
Pal Singh et al. Lipoplex-based therapeutics for effective oligonucleotide delivery: a compendious review
Mohammad Key considerations in formulation development for gene therapy products
CN114848831A (en) Coated nano preparation and preparation method and application of carrier thereof
KR101916941B1 (en) Polymeric nanoparticle composition for delivering pDNA and preparation method thereof
CN106913880A (en) A kind of targeting drug delivery system containing RSPO1 and its preparation and application
Mahapatra et al. Progress with liposomal drug delivery systems: formulation to therapy
Sharma et al. Liposomes: vesicular system an overview
JP4450656B2 (en) Carrier for gene transfer comprising liposome
Wyrozumska et al. Synthetic vectors for genetic drug delivery
Lopes Development and Characterization of RNA-loaded Lipid Nanoparticles prepared by Microfluidics
Li et al. Targeted Gene Delivery via Lipidic Vectors

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

17P Request for examination filed

Effective date: 20030107

17Q First examination report despatched

Effective date: 20040304

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: REGULON, INC.

RIN1 Information on inventor provided before grant (corrected)

Inventor name: BOULIKAS, TENI

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN REFUSED

18R Application refused

Effective date: 20100927