JP2020099326A - Nucleic acid encoding chimeric antigen receptor protein and T lymphocyte expressing chimeric antigen receptor protein - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a treatment with a recombinant T lymphocyte for a tumor of epithelial origin that expresses EGFRvIII or highly expresses EGFR.
A nucleic acid encoding a chimeric antigen receptor protein expressed on the surface of human T cells, wherein the chimeric antigen receptor protein comprises an extracellular binding region, a transmembrane region and an intracellular signal region which are sequentially linked. Wherein the extracellular binding region specifically comprises a single chain antibody scFv(EGFR) which specifically identifies the 287-302 amino acid epitope of human epidermal growth factor receptor EGFR.
[Selection diagram] Figure 1

Description

The present invention relates to the field of treatment of tumor cells, and more particularly to the field of treatment of epithelial-derived tumors that express EGFRvIII or highly express EGFR with recombinant T lymphocytes.

Epidermal Growth Factor Receptor (EGFR) is a transmembrane protein with a molecular weight of 170 KD and an expression product of the protooncogene C-erbB-1 (HER-1), which is widely used in various tissues of the human body. It is distributed in the cell membrane [Alan Wells. Molecules in focus EGF receptor. Int J Biochem Cell Biol, 1999, 31: 637-643.]. Overexpression and/or mutations in most tumors (eg non-small cell lung cancer, bladder cancer, ovarian cancer, breast cancer, head and neck squamous cell carcinoma, glioma, pancreatic adenocarcinoma, esophageal cancer, gastric cancer, prostate cancer, etc.) Is closely associated with tumor development/progression, malignant transformation, metastasis and prognosis [Jose B. Why the epidermal growth factor receptor? The rational for cancer therapy [J]. Oncologist, 2002, 7 (4): 2-8.]. Therefore, EGFR is an important target in tumor therapy. In addition, studies have shown that the EGFR287-302 epitope is exposed only in EGFRvIII or overexpressed EGFR tumors, and in normal tissues the epitope is hidden [Gan HK et al. Targeting of a conformationally exposed, tumor- specific epitope of EGFR as a strategy for cancer therapy. Cancer Res, 2012, 72(12):2924-2930.]. It is suggested that the EGFR287-302 epitope is one of the ideal sites for the treatment of related tumors targeting EGFR.

Antibodies against the EGFR287-302 epitope have already been developed and show excellent tumor-specific killing effect. However, antibody therapy has a limited half-life of the antibody in circulating in the body and generally has a half-life of approximately 23 days or less. As such, continuous administration and/or escalation of dose is required for antibody treatment of tumors, which leads to increased treatment costs for patients and in some cases may require termination of treatment. Further, the therapeutic antibody may cause an allergic reaction in the body as a heterologous protein, and there is also a risk of producing a neutralizing antibody against the therapeutic antibody.

The effect of T lymphocytes on the tumor immune response has been emphasized. Adoptive immunotherapy based on T lymphocytes has some efficacy in some tumors, and while such immunotherapy can overcome the above drawbacks of antibody therapy, it has therapeutic efficacy in most tumors. Not satisfactory [Grupp SA et al. Adoptive cellular therapy. 2011, 344:149-72.]. Recently, based on the discovery that the specificity of cytotoxic T lymphocytes for target cells depends on the T cell receptor (T Cell Receptor, TCR), the scFv of an antibody against a tumor cell-associated antigen is compared with the T cell receptor CD3ζ or It is fused with an activation motif of an intracellular signal such as FcεRIγ to form a chimeric antigen receptor (CAR), which is genetically modified on the surface of T cells by a method such as lentivirus infection. Such CAR T cells can selectively kill tumors by selectively targeting T lymphocytes to tumor cells in a manner not restricted by the major histocompatibility complex (MHC). CAR T cells are one of the new immunotherapeutic measures in the field of tumor immunotherapy [Schmitz M et al. Chimeric antigen receptor-engineered T cells for iImmunotherapy of Cancer. J Biomed Biotechnol, 2010, doi:10.1155/2010/956304. ].

The chimeric antigen receptor contains an extracellular binding region, a transmembrane region and an intracellular signal region. Usually, the extracellular region contains scFv that can identify tumor-associated antigens, the transmembrane region uses the transmembrane regions of molecules such as CD8 and CD28, and the intracellular signal region uses the immunoreceptor tyrosine-motif (immunoreceptor tyrosine- based activation motif (ITAM), eg, intracellular signal regions such as CD3ζ (ie, CD3 zeta, abbreviated as CD) or FcεRIγ and costimulatory signal molecules CD28, CD137, CD134.

Those in which the intracellular signal region contains only ITAM are CAR T cells of the first generation, in which each part of the chimeric antigen receptor is linked like scFv-TM-CD3ζ. Such CAR T cells cause cytotoxic effects of antitumor, but have low cytokine secretion and cannot exert a permanent antitumor effect in the body [Zhang T. et al. Chimeric NKG2D-modified T cells inhibit systemic T -cell lymphoma growth in a manner involving multiple cytokines and cytotoxic pathways, Cancer Res 2007, 67(22):11029-11036.].

The second-generation CAR T cells that have developed thereafter contain the intracellular signal region of CD28 or CD137 (also called 4-1BB), in which each part of the chimeric antigen receptor is scFv-TM-CD28 -ITAM. Or it is linked like scFv-TM-/CD137-ITAM. B7/CD28 or 4-1BBL/CD137 costimulatory action occurring in the intracellular signal region causes continuous proliferation of T cells, and raises the level of T cells that secrete cytokines such as IL-2 and IFN-γ, At the same time, it improves the in vivo survival and antitumor effects of CAR T [Dotti G. et al. CD28 costimulation improves expansion and persistence of chimeric antigen receptor modified T cells in lymphoma patients. J Clin Invest, 2011, 121(5):1822- 1826.].

In the third-generation CAR T cells that have been developed in recent years, inside each part of the chimeric antigen receptor is linked as scFv-TM-CD28-CD137-ITAM or scFv-TM-CD28-CD134-ITAM. , CAR T to further improve in vivo survival and antitumor effect [Carpenito C. et al. Control of large established tumor xenografts with genetically retargeted human T cells containing CD28 and CD137 domains. PNAS, 2009, 106(9): 3360- 3365.].

CAR T cells have a fascinating potential in tumor immunotherapy, but potential risks also need to be considered. For example, when a specific antigen recognized by CAR is underexpressed in a normal tissue, CAR T cells damage normal tissue expressing the corresponding antigen. For example, carbonic anhydrase IX (CAIX), an antigen expressed in tumor cells of patients with renal cell carcinoma, was first used clinically in the case of adoptive treatment of CAR T cells, and the off-target effect of CAR cells was reported for the first time. It is also a case. Patients develop level 2-4 hepatotoxicity after several doses of CAR T cells. In the analysis, the cause was low expression of CAIX in intrahepatic cholangioepithelial cells, unavoidably discontinuing the clinical trial, as well as eliminating all assessments of patient efficacy. [Stoter G. et al. Treatment of metastatic renal cell carcinoma with autologous T-lymphocytes genetically retargeted against carbonic anhydrase IX: first clinical experience. J clin oncol, 2006, 24 (13): e20-e22.; Ngo MC. et al Ex vivo gene Transfer for improved adoptive immunotherapy of cancer. Human Molecular Genetics, 2011, R1-R7].

Excessive costimulatory signals in CAR also reduce the threshold required for activation of effector cells and are active under conditions in which genetically modified T cells are induced by low levels of antigen or no antigen induction. When released, a large amount of cytokine is released, which may cause a so-called “cytokine storm”. Such signal leakage causes off-target cytotoxicity, resulting in non-specific tissue damage. For example, in the course of treating a patient with end-stage colon cancer with clinical liver and lung metastases by a third-generation CAR for Her2, the patient suddenly died due to a so-called “cytokine” with low expression of Her2 in normal lung tissue [Morgan RA. et al Report of a serious adverse event following the administration of T cells transduced with a chimeric antigen receptor recognizing Erbb2. Molecular Therapy, 2010, 18 (4): 843-851.].
Therefore, in the present field, a tumor treatment method using CAR T lymphocytes that overcomes the above-mentioned drawbacks has been earnestly desired.

The first aspect of the present invention relates to a nucleic acid encoding a chimeric antigen receptor protein expressed on the surface of T cells, wherein the chimeric antigen receptor protein comprises an extracellular binding region, a transmembrane region and an intracellular signal region which are linked in order. Wherein the extracellular binding region comprises a single chain antibody scFv (EGFR) that specifically identifies the 287-302 amino acid (EGFR287-302) epitope of human epidermal growth factor receptor EGFR. The extracellular binding region of the chimeric antigen receptor protein is linked to the transmembrane region of CD8 or CD28 at the hinge region of CD8, and the intracellular signal region is adjacent to the transmembrane region. The polynucleotide of the present invention may be in DNA form or RNA form. DNA forms include cDNA, genomic DNA or artificially synthesized DNA. The DNA may be single-stranded or double-stranded. The DNA may be the coding strand or non-coding strand.

The nucleic acid codon encoding the amino acid sequence of the chimeric antigen receptor protein of the present invention may be degenerate, that is, multiple kinds of degenerate nucleic acid sequences encoding one amino acid sequence are all included in the scope of the present invention. .. Degenerate nucleic acid codons encoding the corresponding amino acids are known in the art. The present invention further relates to variants of the above polynucleotides which encode polypeptides or fragments, analogs and derivatives of the polypeptides having the same amino acid sequence as the present invention. Variants of this polynucleotide may be naturally occurring allelic variants or non-naturally occurring variants. These nucleotide variants include substitution variants, deletion variants and insertion variants. As is known in the art, allelic variants are alternative forms of polynucleotides that may be substitutions, deletions or insertions of one or more nucleotides, but are substantially of the encoding polypeptide. It does not change its function.

The invention further comprises at least 50%, preferably at least 70%, more preferably at least 80%, most preferably at least 90% or at least 95% homology between the two sequences and the two sequences described above. A polynucleotide having a property. The present invention particularly relates to polynucleotides that can hybridize with the polynucleotides of the present invention under stringent conditions. In the present invention, “strict conditions” means (1) low ionic strength and high temperature, for example, hybridization and elution at 0.2×SSC, 0.1% SDS, 60° C., or (2) denaturing agent during hybridization, For example, add 50% (v/v) formamide, 0.1% fetal bovine serum/0.1% Ficoll, etc. at 42°C, or (3) the homology between two sequences is at least 90% or more, preferably 95% or more. Hybridize only when. The polypeptide encoded by the hybridizable polynucleotide has the same biological function and activity as the mature polypeptide represented by SEQ ID NO:2.

Monoclonal antibody that specifically identifies the 287-302 amino acid epitope of human epidermal growth factor receptor EGFR is published in Chinese Patent Documents CN102405235 and CN101602808B, and other known or future discovered monoclonal antibody that identifies the epitope is also available. It can be used for producing a single chain antibody in a chimeric antigen receptor protein encoded by the nucleic acid of the present invention. Single chain antibodies can be produced by genetic engineering methods or chemical synthesis methods based on the sequences disclosed in the above-mentioned documents. The term "single chain antibody (scFv) fragment" used in the present invention is an antibody fragment defined as follows, which comprises a heavy chain variable region (VH) and a light chain variable region (VH) linked by a linker (linker). In recombinant proteins, including the VL), the linker associates the two domains and ultimately forms the antigen binding site. The size of the scFv is usually 1/6 that of a complete antibody. The single chain antibody preferably has a single amino acid chain sequence encoded by a single nucleotide chain.

Molecular Cloning Used in the Invention: Laboratory Manual Using conventional techniques known in the art, such as amino acid deletion, insertion, substitution, increase, and/or transfer and/or other modification methods alone. Alternatively, they may be used in combination and further modified. It is well known to introduce a method of such modification into the DNA sequence of an antibody amino acid sequence. See, eg, Sambrook, Molecular Cloning: Laboratory Manual, Cold Spring Harbor Laboratory (1989) N.Y. The modification is preferably performed at the nucleic acid level. The single chain antibody further includes a derivative thereof. The above-mentioned single chain antibody derivative is, for example, a method for producing a chimeric antibody described in WO 89/09622, a method for producing a humanized antibody described in EP-A10239400 and WO90/07861, WO91/10741, WO94/02602 and WO96/. 33735, including but not limited to methods for producing xenoantibodies, such as human antibodies in mice.

The term "specifically discriminate" according to the present invention means that the bispecific antibody of the present invention does not or does not cross-react with any polypeptide other than the antigen of interest. Its degree of specificity can be determined by immunological techniques, including, but not limited to, immunoblot, immunoaffinity chromatography, flow cytometric analysis and the like. In the present invention, the specific identification is preferably confirmed by a flow cytometry technique, but specifically, the standard of the specific identification is determined by common knowledge in the field known to those skilled in the art.

The transmembrane region is selected from the transmembrane regions of proteins such as CD8 or CD28. CD8 or CD28 are natural markers on the surface of T cells. The human CD8 protein is a heterodimer, consisting of αβ or γδ duplexes, and in one embodiment of the invention, the transmembrane region is selected from the transmembrane region of CD8α or CD28. In addition, since the CD8α hinge region (hinge) is a flexible region, CD8 or CD28, the transmembrane region and the hinge region are used to connect the target discrimination domain scFv of the chimeric antigen receptor CAR and the intracellular signal region. be able to.

The intracellular signal region is selected from the intracellular signal regions of CD3ζ, FcεRIγ, CD28, CD137, CD134 proteins, and combinations thereof. The CD3 molecule consists of five subunits, among which the CD3ζ subunit (also called CD3 zeta, abbreviated as Z) contains three ITAM motifs, which are important signaling regions in the TCR-CD3 complex. is there. CD3δZ is a CD3ζ sequence that does not have a mutant ITAM motif and is usually the construction of a negative control in the practice of the present invention. FcεRIγ is mainly distributed on the surface of mast cells and basophils, contains one ITAM motif, and is similar to CD3ζ in structure, distribution, and function. In addition, as described above, CD28, CD137, and CD134 are costimulatory signal molecules, and after their binding with ligands, respectively, the co-stimulatory action of their intracellular signal regions causes continuous proliferation of T cells, and Increases the secretion level of cytokines such as -2 and IFN-γ, while improving the survival time and antitumor effect of CAR T cells in the body.

The chimeric antigen receptor protein encoded by the nucleic acid of the present invention comprises an extracellular binding region, a transmembrane region and an intracellular signal region, which are sequentially linked,
scFv(EGFR)-CD8-CD3ζ,
scFv(EGFR)-CD8-CD137-CD3ζ,
scFv(EGFR)-CD28-CD28-CD3ζ,
scFv(EGFR)-CD28-CD28-CD137-CD3ζ,
And a combination thereof, wherein the first CD28 in the related chimeric antigen receptor protein represents its transmembrane region and the second CD28 represents its intracellular signal region.

In one embodiment of the invention, the nucleic acid of the invention has the sequence set forth in SEQ ID NOs: 1-4. In another embodiment of the present invention, the nucleic acid of the present invention is a nucleic acid encoding a chimeric antigen receptor protein having any of SEQ ID NOs: 31-34.

The second aspect of the present invention includes a vector containing a nucleic acid encoding the chimeric antigen receptor protein expressed on the surface of the T cell. In one specific embodiment, the vector used in the present invention is the lentiviral plasmid vector pPWT-eGFP. The plasmid belongs to the third generation self-inactivating lentiviral vector system, which encodes a total of three plasmids, namely the packaging plasmid psPAX2, which encodes the proteins Gag/Pol and Rev proteins, VSV-G protein. It has the envelope plasmid PMD2.G and the empty vector pPWT-eGFP and can be used for integration into the nucleic acid sequence, ie for coding the nucleic acid sequence of CAR.

In the empty vector pPWT-eGFP (which itself is a mock in a later test), the enhanced green fluorescent protein (eGFP) was enhanced by the elongation factor-1α (elongation factor-1α, EF-1α) promoter. Regulates expression. On the other hand, the recombinant expression vector pWPT-eGFP containing the target nucleic acid sequence encoding CAR is a ribosomal skipping sequence 2A (f2A) derived from foot and mouth disease virus (food and mouthvires disease, FMDV). Co-expression is realized.

The third aspect of the present invention includes a virus containing the above vector. The virus of the present invention includes a virus having infectivity after packaging, and also includes a packaged virus containing components necessary for packaging into a virus having infectivity. Other T-cell transducing viruses known in the art and corresponding plasmid vectors can also be used in the present invention.

In one embodiment of the invention, the virus is a lentivirus comprising the pWPT-eGFP-F2A-CAR recombinant vector (ie containing scFv(EGFR)-CAR).
A fourth aspect of the present invention comprises a recombinant T lymphocyte transduced with the nucleic acid of the present invention or the above recombinant plasmid containing the nucleic acid of the present invention, or a viral system containing the plasmid. As a usual nucleic acid transduction method in this field, both a non-viral transduction method and a viral transduction method can be used in the present invention. Non-viral transduction methods include electroporation and transposon methods. The nucleofector nucleofection device recently researched and developed by Amaxa can directly introduce a foreign gene into the cell nucleus to achieve efficient transfection of a target gene.

In addition, transfection efficiency of transposon systems such as Sleeping Beauty system or PiggyBac transposon has been significantly improved over conventional electroporation methods, and the combination of the nucleofector transfection device and the SB Sleeping Princess transposon system has already been reported. [Davies JK. et al. Combining CD19 redirection and alloanergization to generate tumor-specific human T cells for allogeneic cell therapy of B-cell malignancies. Cancer Res, 2010, 70(10): OF1-10.] It also has a high efficiency and can realize site-specific integration of a target gene.

In one embodiment of the invention, the method of transfecting T lymphocytes that achieves modification of the chimeric antigen receptor gene is a viral, eg, retroviral or lentiviral, based transfection method. This method has advantages such as high transfection efficiency, stable expression of foreign genes, and reduction of the time for in vitro culture of T lymphocytes to a clinical grade number. On the surface of the gene-modified T lymphocyte, the transduced nucleic acid is expressed on the surface by transcription and translation.

By carrying out in vitro cytotoxicity experiments on tumor cells in various cultures, the recombinant T lymphocytes of the present invention in which the chimeric antigen receptor is expressed on the surface of the present invention have a highly specific tumor cell killing effect (also called cytotoxicity). ) Has been proved to have. Therefore, the nucleic acid encoding the chimeric antigen receptor protein of the present invention, the plasmid containing the nucleic acid, the virus containing the plasmid, and the above nucleic acid, the plasmid or the gene-modified T lymphocyte transduced with the virus are effectively used for tumor immunotherapy. Can be used.

FIG. 1 is a structural schematic diagram illustrating a lentiviral vector pWPT-eGFP-F2A-CAR containing an exemplary CAR coding sequence of the present invention. Figure 2 is a schematic diagram showing the ligation relationships between different regions of the CAR of the invention contained in an exemplary lentiviral vector, where eGFP and svFv (EGFR) specific chimeric antigen acceptor by the ribosomal skipping sequence F2A. The body is connected. FIG. 3 shows a nucleic acid electrophoretic pattern in which the lentivirus plasmid of Example 1 was identified by double enzyme cleavage of MluI and SalI. Here, M1 is a DS2000 molecular weight marker (Guangzhou Dongsheng Biological Technology Co., Ltd.) and M2 is a Hind III marker (Guangzhou Dongsheng Biological Technology Co., Ltd.). Lanes 1 to 6 are 1: pWPT-eGFP, 2: pWPT-eGFP-F2A-806-δZ, 3: pWPT-eGFP-F2A-806-Z, 4: pWPT-eGFP-F2A-806-BBZ, 5: pWPT-eGFP-F2A-806-28Z, 6: pWPT-eGFP-F2A-806-28BBZ.

FIG. 4 shows the results of detection of eGFP expressed by cells after infection of CD8 ⁺ T lymphocytes with the virus of Example 2 of the present invention by a flow cytometry technique. FIG. 5 shows the in vitro growth status of CD8 ⁺ T lymphocytes expressing different chimeric antigen receptors (CAR ⁺ ) of Example 2 of the present invention. In the figure, 14 days after virus infection, it was shown that CD8 ⁺ T expressing different chimeric antigen receptors were amplified 35 to 50 times in vitro. FIG. 6 shows the results of detection of the expression status of the surface EGFR287-302 epitope of each tumor cell line used in Example 3 of the present invention by the flow cytometry technique.

Specific Embodiment Hereinafter, the present invention will be further described with reference to specific examples. It is understood that these examples are used only to illustrate the invention and are not meant to limit the scope of the invention. Experimental methods for which specific conditions are not shown in the following examples are described in ordinary conditions, for example, Sambrook et al., “Molecular Cloning: Laboratory Manual (New York: Cold Spring Harbor laboratory Press, 1989)”. According to the conditions, if it is specified in the examples that there is an instruction manual of the reagent company, the recommended conditions of the instruction are followed.

Example 1. Construction of a lentivirus plasmid expressing the chimeric antigen receptor of the present invention Table 1 below shows the ligation order of each part of the chimeric antigen receptor exemplified in the present invention, and the ligation is shown in FIG. To do.

1. Amplification of nucleic acid fragment (1) Amplification of Fv(EGFR) sequence
Amplification of scFv (EGFR) sequence, single-chain dual-function antibody nucleotides 806 / CD3 or hu7B3 / CD3 constructed in this laboratory as a template, the sequence of the template is SEQ ID NO: 10 and in Chinese patent application 201210094008.x, respectively. See 11. The primer pair used for amplification is
Upstream primer 5'-gacatcctgatgacccaatctccatcctc-3' (SEQ ID NO: 5) and downstream primer 5'- tgcagagacagtgaccagagtcccttgg-3' (SEQ ID NO: 6) for amplification of 806 scFv (EGFR),
Then, the upstream primer 5'-gatattcagatgacccagagcccg-3' (SEQ ID NO: 7) and the downstream primer 5'-gctgctcacggtcaccagggtg-3' (SEQ ID NO: 8) were used for amplification of hu7B3 scFv (EGFR).
In both cases, the size of the target amplification band is 720 bp. PCR amplification conditions were pre-denaturation: 94° C., 4 min, denaturation: 94° C., 40 s, annealing: 58° C., 40 s, extension: 68° C., 40 s, 25 cycles, and extension at 68° C., 10 min. The PCR amplified band was confirmed to fit the expected fragment size by agarose gel electrophoresis.
The sequence of the negative control scFv (CD19) was determined by the FMC63-28Z (HM852952.1) sequence of GenBank, and the sequence was obtained by Shanghai Sharp Biotechnology Co., Ltd. in total gene synthesis.

(2) Nucleic acid sequence of other part of chimeric antigen receptor For amplification of the other part of chimeric antigen receptor protein and the hinge region connecting these parts, 1 ml of Trizol (Invitrogen) was used for 1×10 7 healthy subjects. After decomposing the cells by putting them into peripheral blood mononuclear cells (provided by Shanghai Blood Center), total RNA was extracted by the phenol-chloroform method, and ImProm-II (registered trademark) reverse transcription kit (promaga). CDNA was produced by reverse transcription. Using the cDNA produced above as a template, respectively:

(A) Amplification with the upstream primer 5'-cactgtctctgcaaccacgacgccagcg-3' (SEQ ID NO: 9) and the downstream primer 5'-ggtgataaccagtgacaggag-3' (SEQ ID NO: 10) to obtain the CD8α hinge region-transmembrane region. Pre-denaturation: 94° C., 4 min, denaturation: 94° C., 30 s, annealing: 58° C., 30 s, extension: 68° C., 30 s, 25 cycles, followed by extension at 68° C., 10 min. The theoretical size of the band was 198 bp and the amplified product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

(B) Amplification with the upstream primer 5'-cactgtctctgcaaccacgacgccagcg-3' (SEQ ID NO: 11) and the downstream primer 5'-gaggtcgacctacgcgggggcgtctgcgctcctgctgaacttcactctggtgataaccagtg-3' (SEQ ID NO: 12) to CD8α hinge region-transmembrane region δ-delta Z (delta Z) Obtaining and PCR amplification conditions are the same as above. The theoretical size of the band was 234 bp and the amplified product was confirmed by agarose gel electrophoresis to match the theoretical size.

(C) Amplification with the upstream primer 5'-ttttgggtgctggtggtggttgg-3' (SEQ ID NO: 13) and the downstream primer 5'-gctgaacttcactctggagcgataggctgcgaag-3' (SEQ ID NO: 14) to obtain the CD28 transmembrane region-intracellular signal region fragment, and PCR The amplification conditions were the same as above, the theoretical size of the band was 465 bp, and it was confirmed by agarose gel electrophoresis that the amplified product was in agreement with the theoretical size.

(D) Amplification with the upstream primer 5'-aaacggggcagaaagaaactc-3' (SEQ ID NO: 15) and the downstream primer 5'-cagttcacatcctccttc-3' (SEQ ID NO: 16) to obtain the CD137 intracellular signal region. Similarly, the theoretical size of the band was 126 bp, and the amplification product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

(E) Amplification with the upstream primer 5'-cactggttatcaccagagtgaagttcagcaggagc-3' (SEQ ID NO: 17) and the downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18) to obtain the CD3 zeta signal region, PCR amplification conditions are the same as above The theoretical size of the band was 339 bp, and the amplified product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

2. Assembly of nucleic acid fragments
(A) The upstream primer 5'-accacgacgccagcgccg-3' (SEQ ID NO: 19) and the downstream primer 5'-cacccagaaaataataaag-3' (SEQ ID NO: 20) were assembled to obtain the CD8α hinge region-CD28 transmembrane region. , CD8α hinge region (50 ng) + CD28 transmembrane region (50 ng), pre-denaturation: 94°C, 4 min, denaturation: 94°C, 30s, annealing: 60°C, 30s, extension: 68°C, 30s for 5 cycles After that, it was extended at 68°C for 10 min, supplemented with DNA polymerase and upstream/downstream primers, and then PCR-amplified for 25 cycles. Amplification conditions were: pre-denaturation: 94°C, 4 min, denaturation: 94°C, 30 s, annealing: Elongation at 60° C., 30 s: 68° C., 30 s, 25 cycles, and extension at 68° C., 10 min The theoretical size is 216 bp. It was confirmed by agarose gel electrophoresis that the amplified product was in agreement with the theoretical size.

(B) Assembly and amplification with an upstream primer 5'-agagtgaagttcagcaggagcgcag-3' (SEQ ID NO: 21) and a downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18) to produce a 4-1BB intracellular signal region and CD3 zeta, that is, BBZ was obtained, and the conditions of assembly and PCR amplification were the same as above. The theoretical size of the band was 465 bp, and the amplified product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

(C) The upstream primer 5'-cactgtctctgcaaccacgacgccagcg-3' (SEQ ID NO: 22) and the downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18) are equimolar to the CD8α hinge region-transmembrane region and CD3 zeta (about 50 ng). A) and PCR to obtain CD8-CD3 zeta (ie CD8-Z), the conditions of assembly and PCR amplification being the same as above. The theoretical size is 537 bp. It was confirmed by agarose gel electrophoresis that the amplified product was in agreement with the theoretical size.

(D) The upstream primer 5'-cactgtctctgcaaccacgacgccagcg-3' (SEQ ID NO: 23) and the downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18) were used to assemble the CD8α hinge region-transmembrane region with BBZ, and then PCR was performed. A fragment: CD8-CD137-CD3 zeta (ie CD8-BBZ) was obtained, and the conditions of assembly and PCR amplification were the same as above. The theoretical size is 663 bp. It was confirmed by agarose gel electrophoresis that the amplified product was in agreement with the theoretical size.

(E) With the upstream primer 5'-accacgacgccagcgccg-3' (SEQ ID NO: 24) and the downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18), the same assembly as above from CD8α hinge region-CD28 transmembrane region and Z A fragment of interest: CD8 hinge region-CD28 transmembrane region-28Z intracellular region was obtained by PCR amplification, and the conditions of assembly and PCR amplification were the same as above. The theoretical size of the band was 678 bp and the amplified product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

(F) With the upstream primer 5'-accacgacgccagcgccg-3' (SEQ ID NO: 19) and the downstream primer 5'-cgaggtcgacctagcgagggggcagggcctgcatg-3' (SEQ ID NO: 18), the CD8 hinge region was replaced with the CD28 transmembrane region-intracellular signal region fragment and BBZ. After assembly, a fragment of interest: CD8 hinge region-CD28TM-28BBZ was obtained, its theoretical size was 804 bp, and the assembly/amplification product was confirmed by agarose gel electrophoresis to match the theoretical size.

(G) equimolar δZ, Z and 28BBZ nucleic acid fragments each having a hinge region and a transmembrane region obtained by the above amplification, each equimolar nucleic acid sequence of a single chain antibody scFv806 or scFvCD19 (mass about 50 ng) And the PCR is performed under the same conditions as the above-described fragment assembly and PCR amplification. The chimeric antibodies 806-δZ, 806-Z, 806-BBZ, 806-28Z and 806 are assembled in the form shown in FIG. A nucleic acid sequence encoding -28BBZ was obtained.

3. Construction of plasmid vector The vector system used in this example belongs to the third generation self-inactivating lentiviral vector system, which is a package encoding a total of three plasmids, namely the proteins Gag/Pol and Rev proteins. Ng plasmid psPAX2, envelope plasmid PMD2.G encoding VSV-G protein and a recombinant expression vector encoding the target gene CAR based on the empty vector pPWT-eGFP.

In the empty vector pPWT-eGFP, the elongation factor-1α (elongation factor-1α, EF-1α) promoter regulates the expression of enhanced green fluorescent protein (eGFP), while encoding the target gene CAR. In this recombinant expression vector, eGFP and the target gene CAR were co-expressed with a foot and mouth disease virus-derived ribosome skipping sequence (FMDV, ribosomal skipping sequence, F2A). F2A is a core sequence derived from 2A of foot-and-mouth disease virus (also referred to as “self-cleaving polypeptide 2A”), has the “self-cleaving” function of 2A, and can realize coexpression of upstream and downstream genes. 2A provides an effective and feasible strategy for constructing multicistronic vector for gene therapy due to its advantages of high cleavage efficiency, good balance of upstream/downstream gene expression, and short sequence of itself. did. In particular, in immunotherapy with chimeric antigen receptor gene-modified T lymphocytes, coexpression of the target gene and GFP or eGFP is often realized using the sequence, and CAR expression is detected by detecting GFP or eGFP. It can be detected indirectly.

In this example, a lentivirus expression vector that co-expresses dGFP and specific CAR linked via F2A was constructed, and is generically called pWPT-eGFP-F2A-CAR. The method for assembling each part of eGFP-F2A-CAR is as follows.

The method of primer assembly yielded a fragment containing the F2A (66 bp)-CD8α signal peptide (63 bp) and a small nucleic acid (approximately 18 bp) sequence that assembles with upstream eGFP and downstream CAR, with a theoretical size of 165 bp, The primers are as follows.
5'-attcaaagtctgtttcacgctactagctagtccg-3' (SEQ ID NO:25)
5'-gtgaaacagactttgaattttgaccttctgaagttggcaggagacgttgagtccaac-3' (SEQ ID NO:26)
5'-agcggcaggagcaaggcggtcactggtaaggccatgggcccagggttggactcaacgtc-3' (SEQ ID NO: 27)
5'-ctcctgccgctggccttgctgctccacgccgccaggccggacatcctgatgacccaatc-3' (SEQ ID NO: 28)

The conditions for assembly with primers were as follows: predenaturation: 94° C., 4 min, denaturation: 94° C., 20 s, annealing: 50° C., 20 s, extension: 68° C., 30 s, 25 cycles, and extension at 68° C. for 10 min. It was confirmed by agarose gel electrophoresis that the amplified product was in agreement with the theoretical size.
Amplify with the upstream primer 5'-cttacgcgtcctagcgctaccggtcgccaccatggtgagcaagggcgaggag-3' (SEQ ID NO: 29) and the downstream primer 5'-gctactagctagtccggacttgtacagctcgtccatg-3' (SEQ ID NO: 30) to obtain the target gene eGFP, and use the pWPT-eGFP empty vector as a template and PCR amplification as a template. The conditions are: pre-denaturation: 94°C, 4 min, denaturation: 94°C, 40s, annealing: 56°C, 40s, extension: 68°C, 40s, 25 cycles, extension at 68°C, 10min, theoretical size 735 At bp, the amplification product was confirmed by agarose gel electrophoresis to match the theoretical size.

The upstream primer 5'-cttacgcgtcctagcgctaccggtcgccaccatggtgagcaagggcgaggag-3' (SEQ ID NO: 29) and the downstream primer 5'-gaggtcgacctacgcgggggcgtctgcgctcctgctgaacttcactctggtgataaccagtg-3' (SEQ ID NO: 12) were obtained with the above-mentioned 8'-SEQ ID NO. (About 80 ng) was used to assemble to obtain eGFP-F2A-806-δZ, and the assembly conditions were as follows: predenaturation: 94°C, 4 min, denaturation: 94°C, 40s, annealing: 62°C, 40s, extension: 68. After 5 cycles at 140°C for 40°C, after supplementing with an appropriate volume of DNA polymerase and upstream/downstream primers, PCR amplification was performed for 25 cycles, and the amplification conditions were pre-denaturation: 94°C, 4 min, denaturation: 94°C, 40s, Annealing: 62°C, 40s, extension: 68°C, 140s. The theoretical size was 1861 bp, and the amplified product was confirmed to be in agreement with the theoretical size by agarose gel electrophoresis.

Equimolar F2A and CD8α signal peptide fragments obtained above with the upstream primer 5'-cttacgcgtcctagcgctaccggtcgccaccatggtgagcaagggcgaggag-3' (SEQ ID NO: 29) and the downstream primer 5'-gaggtcgacctagcgagggggcagggcctgcatgtgaag-3' (SEQ ID NO: 18) , 806-BBZ, CD19-BBZ, 806-28Z and 806-28BBZ (about 80 ng), respectively. Assembly conditions: pre-denaturation: 94°C, 4 min, denaturation: 94°C, 40s, annealing: 62°C, 40s, extension: 68°C, 140s, after 5 cycles, supplement with appropriate volume of DNA polymerase and upstream/downstream primers After that, PCR amplification was performed for 25 cycles, and the amplification conditions were pre-denaturation: 94° C., 4 min, denaturation: 94° C., 40 s, annealing: 62° C., 40 s, extension: 68° C., 140 s.

The resulting eGFP-F2A-806-Z, eGFP-F2A-806-BBZ, eGFP-F2A-806-28Z and eGFP-F2A-806-28BBZ have theoretical sizes of 2164 bp, 2290 bp, 2305 bp, respectively. At 2431 bp, the amplification product was confirmed by agarose gel electrophoresis to match the theoretical size. Here, the enzyme cleavage sites of MluI and SalI were introduced at the upper and lower ends of the reading frame. The target gene eGFP-F2A-CAR obtained above was double-enzyme-digested with MluI and SalI, and ligated to pWPT vector which was also double-enzyme-digested, and a lentivirus expressing each chimeric antigen receptor constructed. Vectors were identified by enzymatic cleavage of MluI and SalI (FIG. 3) and confirmed by sequencing for lentiviral packaging.
As mentioned above, eGFP-F2A-CAR is transcribed into a single mRNA, but it is translated into two proteins such as eGFP and the anti-EGFR287-302 chimeric antigen receptor, and the anti-EGFR287-302 chimera by the action of the CD8α signal peptide. Localizes the antigen receptor to the cell membrane.

4. Transfection of plasmid into 293T and packaging of lentivirus
293T cells (ATCC: CRL-11268) cultured from the 6th to the 10th generation were inoculated into a 10 cm dish at a density of 6 × 10 ⁶ and cultured overnight at 37°C and 5% CO ₂ for use in transfection. Prepared The medium was DMEM containing 10% fetal bovine serum (PAA) (PAA), and the culture medium was changed to serum-free DMEM the next day, about 2 hours before transfection.

The procedure of transfection is as follows.
4.1 20 μg empty plasmid pWPT-eGFP (mock control) or 20 μg target gene plasmid pWPT-eGFP-F2A-CAR together with 15 μg packaging plasmid PAX2 and 6 μg envelope plasmid pMD2.G in 500 μL MillQ was dissolved in water and mixed uniformly.
4.2 62 μL of 2.5 M CaCl 2 (Sigma) was added drop by drop and vortex mixed uniformly at 1200 rpm/min.
4.3 Finally, add 500 μL of 2×HeBS (280 mM NaCl, 10 mM KCl, 1.5 mM Na2HPO4・2H2O, 12 mM glucose, 50 mM Hepes (Sigma), pH 7.05, 0.22 μM filtration/disinfection) drop by drop at 1200 rpm/ Vortex mixed uniformly for 10 s at min.
4.4 Immediately, each drop was placed in a petri dish, shaken gently and uniformly, cultured at 37°C, 5% CO2 for 4 to 6 hours, and then changed to DMEM containing 10% fetal bovine serum.

The day after transfection, the transfection efficiency (ie the percentage of cells showing green fluorescence) was observed and a positive transfection efficiency of -80% was considered a successful transfection experiment. 48 h or 72 h after transfection, the virus was collected by filtration with a 0.45 μm filter (Millipore), and then centrifuged in a Beckman Optima L-100XP ultracentrifuge at 28000 rpm at 4°C for 2 hours, and the supernatant was centrifuged. The precipitate obtained by centrifugation is resuspended in 1/10 to 1/50 of the original volume of Quantum 007 culture solution (PAA), dispensed at 100 μL/tube, and stored frozen at -80°C. And prepared for virus titration or infection of T lymphocytes.

5. Titer determination of lentivirus packaged with mock or eGFP-F2A-CAR On the first day, inoculate 96-well culture plates with 100 μL/well of 293T cells at 1×10 ⁵ /mL at 37°C, The cells were cultured in 5% CO ₂ and the culture medium was DMEM containing 10% fetal bovine serum. On the second day, discard 50 μL/well of culture supernatant, add 50 μL/well of the above fresh culture medium to contain polybrene at a final concentration of 6 μg/mL, and add 30 μC at 37°C, 5% CO ₂ . Incubated for min. Virus stocks were added at 10 μL/well or virus concentrate at 1 μL/well, diluted 5-fold, 4 gradients, 2 duplicate wells, and incubated at 37°C, 5% CO ₂ . .. 48 hours after infection, eGFP was detected by a flow cytometer, and the number of cells with a positive rate of 5 to 20% is suitable, and the titer (U/mL) = positive rate x dilution factor x 100 x 104 Calculated. The titer of virus packaged by the calcium phosphate transfection method was about 0.5-2×10 ⁶ U/mL, and the titer of virus measured after concentration was about 2×10 ⁷ U/mL.

Example 2. Infection of CD8 ⁺ T lymphocytes with recombinant lentivirus Human peripheral blood mononuclear cells (provided by Shanghai Blood Center) were obtained from peripheral blood of healthy subjects by density gradient centrifugation, and CD8 ⁺ T lymphocytes were obtained from the peripheral blood mononuclear cells. give spherical magnetic beads (Stem Cell Technologies) CD8 ⁺ T lymphocytes by negative separation method, the isolated CD8 ⁺ T lymphocytes, to detect the purity of CD8 ⁺ T lymphocytes by flow cytometry, CD8 ⁺ T lymphocytes A positive rate of ≧95% is preferable, and the procedure was advanced to the next step. Quantum 007 lymphocyte culture medium (PAA) was added at a density of about 1 × 10 ⁶ /mL and cultured, and the cells:magnetic beads were covered with both anti-CD3 and CD28 antibodies so that the ratio was 1:1. Magnetic beads (Invitrogen) and recombinant human IL-2 (Shanghai Hua Neoplasm High-Technology Co., Ltd.) at a final concentration of 100 U/mL were placed and stimulated for 24 hours. Then, at MOI≈5, CD8 ⁺ T lymphocytes were infected with the above recombinant lentivirus. The infected cells were passaged every other day at a density of 5×10 ⁵ /mL, and recombinant human IL-2 at a final concentration of 100 U/mL was added to the lymphocyte culture medium.

For infected CD8 ⁺ T lymphocytes, the expression of each different chimeric antigen receptor was detected by flow cytometry on day 7 of culture, and eGFP-positive cells, namely chimeric antigen receptor, were detected due to coexpression of eGFP and CAR. Positive cells expressing the body were detected (Fig. 4). The positive rate of virus-infected CD8 ⁺ T lymphocytes expressing different chimeric antigen receptors using T lymphocytes not infected as a negative control is shown in the table below. From the result of the positive rate, it was found that CAR ⁺ T lymphocytes having a certain positive rate can be obtained by the lentivirus infection method.

CD8 ⁺ T lymphocytes were subcultured every other day at a cell density of 5 × 10 ⁵ /ml, counted and passaged after infection with viruses packaged with different chimeric antigen receptors. IL-2 (final concentration 100 U/ml) was added to the cell culture medium, and it was amplified about 35 to 55 times on day 14 of culture (see FIG. 5) to express different chimeric antigen receptors CD8 ⁺ T. It has been found that lymphocytes can be expanded to a certain number outside the body and provide security for subsequent in vitro toxicity and in vivo studies.

Example 3. EGFR287-302 Epitope-Derived Detection in Epithelial-Derived Tumor Cell Lines Surface of Several Epithelial-Derived Tumor Cells by Fluorescence Activated Cell Sorter (FACSCalibur, Becton Dickinson) Using Flow Cytometer Detection Method The exposure status of the epitope was detected. The materials used are as follows.
(1) The monoclonal antibody CH12 (see Chinese Patent CN 101602808B Examples 1 to 4 for the construction method) that identifies the site constructed in this laboratory was used as the primary antibody (final concentration 20 μg/ml, 100 μL/ sample).
(2) FITC-labeled sheep anti-human IgG was used as a secondary antibody (AOGMA).

The specific method of detecting the status of epitope exposure is as follows.
1. Each of the tumor cells shown in Table 3 in the logarithmic growth phase was inoculated into a 6-cm dish, and the cells were inoculated at a cell density of about 90% in an incubator at 37°C overnight.
2. Cells were digested with 10 mM EDTA and centrifuged at 200 g x 5 min to collect cells. The suspension was resuspended in a phosphate buffer (1% NBS/PBS) containing 1% fetal bovine serum at a concentration of ˜1×10 ⁷ /mL, and 100 μl/tube was placed in a dedicated flow cytometer tube.
3. Centrifuge at 200 g x 5 min and discard the supernatant.
4. Each of the experimental groups contained the test antibody CH12, at the same time one control group contained an irrelevant antibody as a negative control, and the other control group was a PBS blank control containing no antibody. The final concentration of each antibody was 20 μg/ml, and 100 μl was placed in each tube. Place in ice bath for 45 minutes.

5. 2% of 1% NBS/PBS was put into each tube, and the tube was centrifuged at 200 g×5 min, and the total was performed twice.
6. The supernatant was discarded and 100 μl of 1:50 diluted FITC-labeled sheep anti-human IgG was placed in each tube. Place in ice bath for 45 minutes.
7. 2% of 1% NBS/PBS was put into each tube, and the tube was centrifuged at 200 g×5 min, and the total was performed twice.
8. The supernatant was discarded, resuspended in 300 μl of 1% NBS/PBS, and detected by a flow cytometer.
9. The data was analyzed with data analysis software WinMDI 2.9 of the flow cytometer.

As shown in FIG. 6, the EGFR287-302 epitope was not detected in the glioma cell line U87, and exogenous EGFR overexpression U87-EGFR (constructed and stored independently in this experiment, the construction method was Wang H. et al., Identification of an Exon 4-Deletion Variant of Epidermal Growth Factor Receptor with Increased Metastasis-Promoting Capacity. Neoplasia, 2011, 13, 461-471.) and EGFRvIII overexpression U87-EGFRvIII (this experiment) Independently constructed/stored in, and refer to WO/2011/035465 for construction method), exposure of EGFR287-302 epitope was detected, and three pancreatic adenocarcinoma cell lines PANC-1, CFPAC-1 and BxPC-3 were detected. In all cases, exposure of the EGFR287-302 epitope was detected.

Example 4. In vitro toxicity effect experiment of cells expressing chimeric antigen receptor The materials used in the in vitro toxicity experiment are as follows.
The target cells are the 6 types of cells shown in the above table, respectively. Effector cells are cultured in vitro for 12 days and are positive cells in which expression of the chimeric antigen receptor was detected by FACS, and are referred to as chimeric antigen receptor positive (CAR ⁺ ) CD8 ⁺ T lymphocytes.
The effector cell to target cell ratios are optionally 3:1, 1:1 and 1:3 or 5:1, 2.5:1 and 1:1 respectively, with a target cell number of 10,000/well and different effector cell to target cells. The effector cells were matched by ratio. There were 4 duplicate wells in each group, and the average value of 4 duplicate wells was taken. The detection time is 18h or 20h.

Here, each experimental group and each control group are as follows.
Each experimental group: each target cell + CD8 ⁺ T lymphocyte expressing a different chimeric antigen receptor.
Control group 1: maximum release LDH of target cells.
Control group 2: Target cell spontaneous release LDH.
Control group 3: effector cell spontaneously released LDH.

Detection method: CytoTox 96 non-radioactive cytotoxicity detection kit (Promega) was used. The method was a colorimetric based detection method and was used as an alternative to the 51Cr emission method. Lactate dehydrogenase (LDH) was quantitatively measured by CytoTox 96 (registered trademark) detection. LDH is a stable cytoplasmic enzyme that is released when cells are lysed and its release form is basically similar to that of ⁵¹ Cr in radiological analysis. In the released LDH medium supernatant, it can be detected by an enzymatic reaction which is coupled for 30 minutes, and in the enzymatic reaction, LDH can convert a kind of tetrazolid (INT) into red formazan. The amount of red product produced is proportional to the number of lysed cells. Specifically, refer to the instruction manual for the CytoTox 96 non-radioactive cytotoxicity detection kit.

The formula for calculating cytotoxicity is as follows.

The results show the following.
The scFv(EGFR)-806-Z CAR ⁺ expressing CD8 ⁺ T lymphocytes and 806-28BBZ CAR+ CD8+ T lymphocytes of the present invention show very pronounced cytotoxicity against tumor cells U87-EGFRvIII. , 55.5% and 85%, respectively.
Further, the cytotoxicity of the CD8 ⁺ T lymphocytes of the present invention is highly tumor-specific, and the tumor cells that do not expose the EGFR287-302 epitope are highly cytotoxic to the tumor cells U87-EGFRvIII that expose the EGFR287-302 epitope. It showed low cytotoxicity against U87 cells, and both cases were less than 2%. At the same time, the chimeric antigen receptor 806-δZ gene to assess the effect of effector molecules on T cells transfected with a blank control empty plasmid (mock) as evidence of the reliability of the experimental results and on the original T cells as a negative control. Both recombinant T cells showed almost the same low cytotoxicity against U87 and U87-EGFRvIII. The above experiments were measured at an effector cell to target cell ratio of 5:1 and an action time of 20 h.

Also, for different effector cell to target cell ratios, CD8 ⁺ T lymphocytes expressing the scFv(EGFR)-806-Z CAR ⁺ of the present invention and 806-28BBZ CAR ⁺ of the present invention measured at an action time of 18 h. CD8 ⁺ T lymphocytes expose the EGFR287-302 epitope Tumor cells U87-EGFR and U87-EGFRvIII and three pancreatic adenocarcinoma cell lines PANC-1, CFPAC-1 and BxPC-3 all have cytotoxic effects on effector cells The dependence on target-to-target cell ratio gradient is shown, and as shown in the table below, the higher the effector cell to target cell ratio, the higher the cytotoxicity.

When the ratio of effector cells to target cells was 3:1, the chimeric antigen receptor 806-28BBZ CAR ⁺ had a high cytotoxicity of CD8 ⁺ T lymphocytes of U87-EGFR of 98% and U87-EGFRvIII of 81%. The cytotoxicity against the three pancreatic adenocarcinoma cell lines PANC-1, CFPAC-1 and BxPC-3 was 65%, 40% and 70%, respectively.
On the other hand, as a negative control, the CD8 ⁺ T lymphocytes of the chimeric antigen receptor CD19-BBZ CAR ⁺ , which evaluate the effect of non-specific scFv on the chimeric antigen receptor, had cytotoxicity against all three pancreatic adenocarcinoma cell lines. % And shows no dependence on effector cell to target cell ratio gradient.

Claims (11)

A nucleic acid encoding a chimeric antigen receptor protein expressed on the surface of a human T cell, wherein the chimeric antigen receptor protein comprises an extracellular binding region, a transmembrane region and an intracellular signal region, which are sequentially linked, A nucleic acid comprising a single chain antibody scFv (EGFR) whose outer binding region specifically identifies the 287-302 amino acid epitope of human epidermal growth factor receptor EGFR. 2. The nucleic acid of claim 1, wherein the transmembrane region comprises the sequences of the transmembrane region and the hinge region of CD8 or CD28. The nucleic acid according to claim 1 or 2, wherein the intracellular signal region is selected from the intracellular signal region sequences of CD3ζ, FcεRIγ, CD28, CD137, CD134, and combinations thereof. The chimeric antigen receptor protein comprises an extracellular binding region, a transmembrane region, and an intracellular signal region, which are sequentially linked, and the following chimeric antigen receptor protein:
scFv(EGFR)-CD8-CD3ζ,
scFv(EGFR)-CD8-CD137-CD3ζ,
scFv(EGFR)-CD28-CD28-CD3ζ,
scFv(EGFR)-CD28-CD28-CD137-CD3ζ,
Or the combination thereof, wherein the first CD28 in the chimeric antigen receptor protein represents its transmembrane region and the second CD28 represents its intracellular signal region. The nucleic acid according to claim 1, which is selected from the group consisting of nucleic acids encoding a chimeric antigen receptor protein having the sequence of any one of SEQ ID NOs: 31 to 34. The nucleic acid according to claim 1, which has the sequence of any one of SEQ ID NOs: 1 to 4. A vector comprising the nucleic acid according to any one of claims 1 to 6. The vector according to claim 7, which is derived from the lentivirus plasmid pWPT-eGFP. A virus comprising the nucleic acid according to claim 7 or 8. A gene-recombinant T lymphocyte transduced with the nucleic acid according to any one of claims 1 to 6, the vector according to claim 7 or 8, or the virus according to claim 9. ball. A transgenic T lymphocyte, the surface of which expresses a chimeric antigen receptor encoded by the nucleic acid according to any one of claims 1 to 6.