通过肿瘤致敏的DCs活化的CD8^+ T细胞可有效地杀死肿瘤细胞(英文)

Enhanced effect of CD8^+ T cells activated by tumor lysate-pulsed DCs on killing autologous tumor cells

目的:探索肿瘤裂解物负载的DCs诱导活化的初始T细胞介导细胞免疫及活化的T细胞杀死肿瘤细胞的能力。方法:应用黏附法分离外周血中的淋巴细胞和单核细胞,应用GM-CSF +IL-4刺激单核细胞并诱导为iDCs,然后进行分组,应用相应的细胞因子等刺激iDCs转化为mDCs,其中肿瘤裂解物冲击DCs组:冻融抗原负载+TNF-α+IL-1β;无肿瘤裂解物冲击组: TNF-α+IL-1β。再分别用上述DCs与淋巴细胞进行混合培养以刺激混合淋巴细胞中的T细胞转化为细胞毒性T细胞,并进行分组,肿瘤裂解物冲击DCs组:肿瘤裂解物冲击DCs +IL-2 +IL-7;无肿瘤裂解物冲击DCs组:无肿瘤裂解物冲击DCs +IL-2 +IL-7;对照组: IL-2 +IL-7。结果:成功获得iDCs,并高表达CD86、CD80和HLA-DR;相对于其它组,肿瘤裂解物冲击DCs组mDCs更显著上调CD83,且更有效地刺激淋巴细胞增殖;肿瘤裂解物冲击DCs组的CTLs也高表达CD95(Fas)且TNF -α和IFN-γ的表达水平显著提高(P<0.05)。结论:肿瘤裂解物冲击DCs可有效促进T细胞活化、增殖;并显著增强相应CTLs的杀死靶细胞的能力,这为发展DCs +CTLs的免疫治疗肿瘤提供了一种新而且简便的生物治疗模式。

AIM： To evaluate the ability of dendritic cells （DCs） loaded with tumor lysate to initiate cell - mediated immune responses by stimulating naive T cells, and the efficiency of activated T cells to kill autologous tumor cells in vitro. METHODS： The peripheral blood lymphocytes and monocytes were obtained from the advanced renal cell carcinoma patient by conglutination method. The immature dendritic cells were generated in the presence of interleukin -4 （IL - 4 ） and granulocyte/macrophage colony - stimulating factor （ GM - CSF） from monocytes of healthy individuals. These cells were pulsed with tumor lysate or not. Induction of tumor - specific cytotoxic T lymphocytes （CTLs） response by mature dendritic cells （mDCs） was evaluated by the CD95 （Fas） expression assay through FCM and the cytotoxic assay a- gainst autologous human tumor cells. RESULTS ： Human immature dendritic cells and T cells obtained from healthy donors were stimulated with tumor- pulsed dendritic cells. The immature dendritic cells were applied to the cytotoxicity assay against target autologous tumor cells. The CD95 （Fas） expression, IFN - γand TNF - α secreted by the CTLs in tumor lysate - plused DC group were higher than those of other groups. The capacity of the CTLs to kill autologous tumor cells was significantly different（P 〈 0. 05 ）. Antigen- specific DCs vaccine can induce T cells activation and proliferation, thus we can obtain higher proportion of tumor specific cytotoxic T cells（ CTLs）, and enhance the CTLs to secret IFN - γand TNF -α . CONCLUSION ： Our results indicate that monocyte - derived human dendritic cells pulsed with tumor lysate could induce the specific antitumor effect against autologous tumors . This in vitro model offers a new and simple approach to the development of DC ＋ CTL -based immunotherapy.