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@#[Abstract] Objective: To investigate the in vitro cytotoxicity of the chimeric antigen receptor-modified T cells and NK-92MI cells (CAR-NK-92MI cells) and CAR-CD19-T cells against mantle cell lymphoma (MCL). Methods: CAR-T cell technology, successfully obtained in clinical trial of B-lineage acute lymphoblastic leukemia (B-ALL) treatment, was used in this study. In the case of high expression of CD19 antigen in MCL, CAR- CD19-T cells and CAR- CD19-NK-92MI cells targeting CD19 antigen were generated, respectively. Then, their cytotoxicity against MCL cell lines was detected by LDH release assay and the results were verified by flow cytometry. Results: Compared with control group, both CAR-NK-92MI and CAR-CD19-T cells exhibited prominent killing effect against MCLcells（all P<0.01）; in addition, the two CAR cells exhibited high cytotoxicity against K562-CD19 cells but not on K562 cells（all P <0.01）. The death rate of MCL cells from CAR-NK-92MI group was 30%-40% more than that of control group, and the death rate of MCL from CAR-CD19-T group was 40%-50% more than that of control group. Conclusion: Both CAR-NK-92MI and CAR-CD19-T cells exhibited potent cytotoxicity against MCLcells in vitro.
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@#[Abstract] Objective：To investigate whether the proliferation and cytotoxicity of NK-92MI cells can be improved by IL-7 and IL-21 genes modification, and determine the effects of this genetically modified NK-92MI cells on T cells from normal human peripheral blood. Methods：IL-7 and IL-21 gene fragments were constructed into electroporation vector by genetic engineering method, and NK92MI/IL-21 and NK-92MI/IL-7&21 cells were constructed by electroporation transfection. The in vitro proliferation and cytotoxicity of NK-92MI, NK-92MI/IL-21 and NK-92MI/IL-7&21 cells were measured by cell count and flow cytometry assays. Then, normal human PBMCs were co-cultured with NK-92MI, NK-92MI/IL-21 and NK-92MI/IL-7&21 cells in vitro respectively, and the phenotype change of T cells was measured by flow cytometry. In addition, the cytotoxicity between the activated T cells and three NK-92MI cell lines (NK-92MI, NK-92MI/IL-21 and NK-92MI/IL-7&21 cells) as well as the cytotoxicity of the three NK-92MI cells on tumor cells after co-incubation with activated T cells were detected. Results: NK-92MI/IL-21 cell line (highly expressing IL-21) and NK-92MI/IL-7&21 cell line (highly expressing both IL-7 and IL-21) were successfully constructed. The toxicity of NK-92MI, NK-92MI/IL-21 and NK92MI/IL-7&21 cells on Jurkat and K562 cells showed no difference, while the proliferation of NK-92MI/IL-21 and NK-92MI/IL-7&21 cells was increased compared with NK-92MI cells. Furthermore, NK-92MI/IL-21 and NK-92MI/IL-7&21 cells promoted the activation of T cells to a certain degree, and the activated T cells showed merely no cytotoxicity on NK-92MI, NK-92MI/IL-21 and NK-92MI/IL7&21 cells; Meanwhile, the activated T cells did not affect the cytotoxicity of the three NK cells (NK-92MI, NK-92MI/IL-21, and NK92MI/IL-7&21 cells) on K562 cells under their co-existence. Conclusion: The in vitro proliferation of NK-92MI/IL-21 and NK-92MI/ IL-7&21 cells were enhanced after gene modification, which could also stimulate and promote the activation of T cells from peripheral blood. The cytotoxicity assay showed that the activated T cells had no cytotoxicity on NK-92MI, NK-92MI/IL-21, and NK-92MI/IL-7& 21 cells. Meanwhile, the presence of the activated T cells did not affect the cytotoxicity of NK-92MI cells.
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Objective:To study the effects of dexamethasone(DEX)on the cytotoxicity and apoptosis of NK-92MI cells and the mechanisms involved.Methods:NK-92MI cells were treated with different doses of DEX.The proliferative rate and cytotoxicity of the NK-92MI cells were detected by MTT colorimetry.The cell apoptotic rate was observed by flow cytometry with Annexin V and propidium iodide(PI)double staining.The expression of apoptosis-related gene,Bcl-2 and Bax was detected by RT-PCR.Results:After treated with 1?10-8mol/L to 1?10-3mol/L of DEX for 24 h,48 h and 72 h,the proliferation of NK-92MI cells was significant inhibited(P