<p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial&qu... more <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">Usualmente la genitalia de los machos se ha utilizado para definir las diferencias interespecies dentro del subgénero Helcocyrtomyia, ya que las hembras presentan gran similitud en las formas de sus genitalias, y por tanto la diferenciación morfológica de ellas se realiza por asociación geográfica con el macho y por algunos caracteres adicionales como el grado de pigmentación del mesonoto, la longitud de los palpos y la fórmula palpal, entre otros. Los estudios de confirmación taxonómica y biología evolutiva han implementado el uso de secuenciamiento de ADNmt y morfometría como técnicas asociadas a la taxonomía tradicional. El secuenciamiento de genes mitocondriales ha mostrado separaciones exitosas entre especies cercanas, por análisis estadístico de los cambios nucleotídicos (transiciones, transversiones, deleciones, etc.) estimando las relaciones filogenéticas entre ellas. De manera similar las técnicas morfométricas han logrado discriminar especies de insectos, por el análisis de caracteres poligénicos que varían en tamaño y forma. Estos caracteres permiten estimar diferencias interespecíficas atribuibles principalmente a efectos ambientales y genéticos respectivamente.</span></p> <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">Mediante el uso de morfometría, separando el componente genético del ambiental, y del secuenciamiento de un segmento del gen mitocondrial ND4, esta propuesta tiene por objetivo contribuir a la definición de las especies del subgénero Helcocyrtomyia utilizando machos y hembras.</span></p> <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">La morfometría se basará en las mediciones de caracteres de las alas y genitalias. Para el análisis de las variables morfométricas se empleará Análisis Multigrupo de Componentes Principales, Análisis de Componentes Principales Comunes y Análisis de Función Discriminante a partir de los cuales se extraerán componentes de tamaño alométrico [...]
Multiple natural killer (NK) cell-based anticancer therapies are currently under development. Her... more Multiple natural killer (NK) cell-based anticancer therapies are currently under development. Here, we compare the efficiency of genetically modified NK-92 cells expressing chimeric antigen receptors (CARs) at killing NK cell-resistant B-lymphoid leukemia cells to the antibody-dependent cell-mediated cytotoxicity (ADCC) of NK-92 cells expressing a high affinity variant of the IgG Fc receptor (FcγRIII). First, we compared in vitro the abilities of NK-92 cells expressing CD20-targeting CARs to kill primary chronic lymphocytic leukemia (CLL) cells derived from 9 patients with active, untreated disease to the cytotoxicity of NK-92 cells expressing FcγRIII combined with either of the anti-CD20 monoclonal antibodies (mAbs) rituximab or ofatumumab. We found that CAR-expressing NK-92 cells effectively kill NK cell-resistant primary CLL cells and that such a cytotoxic response is significantly stronger than that resulting from ADCC. For studying CAR-expressing NK cell-based immunotherapy in vivo, we established xenograft mouse models of residual leukemia using the human BCR-ABL1(+) cell lines SUP-B15 (CD19(+)CD20(-)) and TMD-5 (CD19(+)CD20(+)), two acute lymphoblastic leukemia (ALL) lines that are resistant to parental NK-92 cells. Intravenous injection of NK-92 cells expressing CD19-targeting CARs eliminated SUP-B15 cells, whereas they had no such effect on TMD-5 cells. However, the intrafemoral injection of NK-92 cells expressing CD19-targeting CAR resulted in the depletion of TMD-5 cells from the bone marrow environment. Comparative studies in which NK-92 cells expressing either CD19- or CD20-targeting CARs were directly injected into subcutaneous CD19(+)CD20(+) Daudi lymphoma xenografts revealed that CD20-targeting CAR is superior to its CD19-specific counterpart in controlling local tumor growth. In summary, we show here that CAR-expressing NK-92 cells can be functionally superior to ADCC (as mediated by anti-CD20 mAbs) in the elimination of primary CLL cells. Moreover, we provide data demonstrating that the systemic administration of CAR-expressing NK-92 cells can control lymphoblastic leukemia in immunocompromised mice. Our results also suggest that the direct injection of CAR-expressing NK-92 cells to neoplastic lesions could be an effective treatment modality against lymphoma.
Various methods of isolation have been described to obtain mesenchymal stem cells (MSC) from umbi... more Various methods of isolation have been described to obtain mesenchymal stem cells (MSC) from umbilical cords [Can and Karahuseyinoglu, 2007]. The starting material differs between the reports, which implies that the isolated cells, although generally showing the ...
An emerging treatment option for chronic lymphocytic leukemia (CLL) is to make cytotoxic immune c... more An emerging treatment option for chronic lymphocytic leukemia (CLL) is to make cytotoxic immune cells express a chimeric antigen receptor (CAR) that recognizes specific surface molecules on CLL cells. Here an mRNA coding for an anti-CD19 CAR was transfected into the NK-92 cell line by electroporation. In contrast to cDNA, mRNA resulted in high transfection efficiency (47.2 +/- 8% versus &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;5% for cDNA) with minimal effect on cell viability. NK-92 cells expressing anti-CD19 CAR killed previously resistant CD19+ B-ALL cell lines, as well as primary CLL cells and therefore may present a safe, cell-based, targeted treatment for patients with CLL.
Monoclonal antibodies (mAbs) are increasingly used in treatment protocols for chronic lymphocytic... more Monoclonal antibodies (mAbs) are increasingly used in treatment protocols for chronic lymphocytic leukemia (CLL). Here we determined (i) the extent of antibody-dependent cellular cytotoxicity (ADCC) of four different mAbs against primary CLL cells, (ii) whether ADCC correlates with antigen density on CLL cells, and (iii) whether allogeneic natural killer (NK) cells display superior ADCC than autologous. Effector cells for ADCC were (i) NK-92 cells not expressing FcR, (ii) NK-92 cells transfected with a high-affinity Fc receptor, (iii) autologous NK cells from patients with CLL, (iv) allogeneic NK cells. Results suggest that ADCC contributes to killing of CLL cells by anti-CD20 antibodies (rituximab and veltuzumab), whereas mAbs against CD22 (epratuzumab) and CD23 (lumiliximab) showed minimal ADCC. The magnitude of anti-CD20 mediated ADCC did not correlate with antigen density of CD20. ADCC was not influenced by the FcR genotype expressed by autologous NK cells. Allogeneic NK cells were superior to autologous NK cells in killing primary CLL cells.
<p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial&qu... more <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">Usualmente la genitalia de los machos se ha utilizado para definir las diferencias interespecies dentro del subgénero Helcocyrtomyia, ya que las hembras presentan gran similitud en las formas de sus genitalias, y por tanto la diferenciación morfológica de ellas se realiza por asociación geográfica con el macho y por algunos caracteres adicionales como el grado de pigmentación del mesonoto, la longitud de los palpos y la fórmula palpal, entre otros. Los estudios de confirmación taxonómica y biología evolutiva han implementado el uso de secuenciamiento de ADNmt y morfometría como técnicas asociadas a la taxonomía tradicional. El secuenciamiento de genes mitocondriales ha mostrado separaciones exitosas entre especies cercanas, por análisis estadístico de los cambios nucleotídicos (transiciones, transversiones, deleciones, etc.) estimando las relaciones filogenéticas entre ellas. De manera similar las técnicas morfométricas han logrado discriminar especies de insectos, por el análisis de caracteres poligénicos que varían en tamaño y forma. Estos caracteres permiten estimar diferencias interespecíficas atribuibles principalmente a efectos ambientales y genéticos respectivamente.</span></p> <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">Mediante el uso de morfometría, separando el componente genético del ambiental, y del secuenciamiento de un segmento del gen mitocondrial ND4, esta propuesta tiene por objetivo contribuir a la definición de las especies del subgénero Helcocyrtomyia utilizando machos y hembras.</span></p> <p class="MsoNormal"><span style="font-size: 8.5pt; font-family: Arial">La morfometría se basará en las mediciones de caracteres de las alas y genitalias. Para el análisis de las variables morfométricas se empleará Análisis Multigrupo de Componentes Principales, Análisis de Componentes Principales Comunes y Análisis de Función Discriminante a partir de los cuales se extraerán componentes de tamaño alométrico [...]
Multiple natural killer (NK) cell-based anticancer therapies are currently under development. Her... more Multiple natural killer (NK) cell-based anticancer therapies are currently under development. Here, we compare the efficiency of genetically modified NK-92 cells expressing chimeric antigen receptors (CARs) at killing NK cell-resistant B-lymphoid leukemia cells to the antibody-dependent cell-mediated cytotoxicity (ADCC) of NK-92 cells expressing a high affinity variant of the IgG Fc receptor (FcγRIII). First, we compared in vitro the abilities of NK-92 cells expressing CD20-targeting CARs to kill primary chronic lymphocytic leukemia (CLL) cells derived from 9 patients with active, untreated disease to the cytotoxicity of NK-92 cells expressing FcγRIII combined with either of the anti-CD20 monoclonal antibodies (mAbs) rituximab or ofatumumab. We found that CAR-expressing NK-92 cells effectively kill NK cell-resistant primary CLL cells and that such a cytotoxic response is significantly stronger than that resulting from ADCC. For studying CAR-expressing NK cell-based immunotherapy in vivo, we established xenograft mouse models of residual leukemia using the human BCR-ABL1(+) cell lines SUP-B15 (CD19(+)CD20(-)) and TMD-5 (CD19(+)CD20(+)), two acute lymphoblastic leukemia (ALL) lines that are resistant to parental NK-92 cells. Intravenous injection of NK-92 cells expressing CD19-targeting CARs eliminated SUP-B15 cells, whereas they had no such effect on TMD-5 cells. However, the intrafemoral injection of NK-92 cells expressing CD19-targeting CAR resulted in the depletion of TMD-5 cells from the bone marrow environment. Comparative studies in which NK-92 cells expressing either CD19- or CD20-targeting CARs were directly injected into subcutaneous CD19(+)CD20(+) Daudi lymphoma xenografts revealed that CD20-targeting CAR is superior to its CD19-specific counterpart in controlling local tumor growth. In summary, we show here that CAR-expressing NK-92 cells can be functionally superior to ADCC (as mediated by anti-CD20 mAbs) in the elimination of primary CLL cells. Moreover, we provide data demonstrating that the systemic administration of CAR-expressing NK-92 cells can control lymphoblastic leukemia in immunocompromised mice. Our results also suggest that the direct injection of CAR-expressing NK-92 cells to neoplastic lesions could be an effective treatment modality against lymphoma.
Various methods of isolation have been described to obtain mesenchymal stem cells (MSC) from umbi... more Various methods of isolation have been described to obtain mesenchymal stem cells (MSC) from umbilical cords [Can and Karahuseyinoglu, 2007]. The starting material differs between the reports, which implies that the isolated cells, although generally showing the ...
An emerging treatment option for chronic lymphocytic leukemia (CLL) is to make cytotoxic immune c... more An emerging treatment option for chronic lymphocytic leukemia (CLL) is to make cytotoxic immune cells express a chimeric antigen receptor (CAR) that recognizes specific surface molecules on CLL cells. Here an mRNA coding for an anti-CD19 CAR was transfected into the NK-92 cell line by electroporation. In contrast to cDNA, mRNA resulted in high transfection efficiency (47.2 +/- 8% versus &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt;5% for cDNA) with minimal effect on cell viability. NK-92 cells expressing anti-CD19 CAR killed previously resistant CD19+ B-ALL cell lines, as well as primary CLL cells and therefore may present a safe, cell-based, targeted treatment for patients with CLL.
Monoclonal antibodies (mAbs) are increasingly used in treatment protocols for chronic lymphocytic... more Monoclonal antibodies (mAbs) are increasingly used in treatment protocols for chronic lymphocytic leukemia (CLL). Here we determined (i) the extent of antibody-dependent cellular cytotoxicity (ADCC) of four different mAbs against primary CLL cells, (ii) whether ADCC correlates with antigen density on CLL cells, and (iii) whether allogeneic natural killer (NK) cells display superior ADCC than autologous. Effector cells for ADCC were (i) NK-92 cells not expressing FcR, (ii) NK-92 cells transfected with a high-affinity Fc receptor, (iii) autologous NK cells from patients with CLL, (iv) allogeneic NK cells. Results suggest that ADCC contributes to killing of CLL cells by anti-CD20 antibodies (rituximab and veltuzumab), whereas mAbs against CD22 (epratuzumab) and CD23 (lumiliximab) showed minimal ADCC. The magnitude of anti-CD20 mediated ADCC did not correlate with antigen density of CD20. ADCC was not influenced by the FcR genotype expressed by autologous NK cells. Allogeneic NK cells were superior to autologous NK cells in killing primary CLL cells.
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