【摘要】 目的以小鼠低免疫原性瘤细胞和高免疫原性瘤细胞与同系脾细胞混合培养为肿瘤免疫体外模型,研究培养后的脾细胞中CD4(+)CD25(+)调节性T细胞(TR)的分布,揭示肿瘤免疫逃逸的机制。方法3种不同高低免疫原性瘤细胞与同系脾细胞混合培养,建立模拟肿瘤免疫的体外模型,以放射性核素掺入法检测混合培养后的脾细胞的增殖,流式细胞术分析TR、CD4(+)干扰素(IFN)γ(+)以及CD4(+)白细胞介素(IL)10(+)T细胞分布状况,ELISA法检测混合脾细胞和肿瘤细胞培养上清液中IFNγ和IL10水平。结果高免疫原性瘤细胞FBL3或H22刺激的同系脾细胞增殖指数较低免疫原性瘤细胞D5刺激的同系脾细胞要高,分别高3倍(D5∶FBL3=4.94∶12.20)和10倍(D5∶H22=4.94∶44.60),而3种瘤细胞刺激的同种脾细胞其增殖指数均较相应的肿瘤免疫组要高(D51.9倍,FBL32.1倍,H221.1倍)。在与低免疫原性瘤细胞D5混合培养的同系脾细胞中,与高免疫原性瘤细胞FBL3或H22相比,含更多的TR(D5∶H22P<0.05)和CD4+IL10+细胞(D5∶FBL3P<0.01,D5∶H22P<0.01),上清液中含更高水平的IL10(P<0.01,P<0.01),而IFNγ水平很低(P<0.01,P<0.01)。结论低免疫原性肿瘤可诱导TR细胞的增生,TR细胞在肿瘤免疫逃逸中有重要作用。更多还原

【Abstract】 Objective To investigate the distribution of regulatory T-lymphocytes in the splenocytes cocultured with syngeneic low-immunogenic tumor cells, as compared with that of highly-immunogenic tumor cells, to investigate the mechanism underlining tumor evasion.Methods Three different immunogenic tumor cells were cocultured with syngeneic splenocytes individually to mimic cancer immunity in vitro. The proliferation response of splenocytes was measured by thymidine incorporation. The distribution of T_R cells、CD4（+） IFN-γ（+） T cells and CD4（+） IL-10（+） T cells were analyzed by flow cytometry. The secretion of IFN-γ and IL-10 in supernatants was measured by ELISA assay. Results The stimulation Index of splenocytes cocultured with syngeneic highly-immunogenic H 22 or FBL₃ was much higher than that of poorly immunogenic melanoma D₅. In each group, stimulation Index of splenocytes cocultured with allogeneic tumor cells was higher than that of the corresponding tumor immunity model. In addition, compared with those of highly-immunogenic tumors, there were more T_R, CD4（+）IL-10（+） and less CD4（+）IFN-γ（+） T cells in the splenocytes, and higher IL-10 and lower IFN-γ levels in the supernatant of the splenocytes stimulated with low-immunogenic D₅ cells. Conclusion Poorly-immunogenic tumor cells can induce the proliferation of T_R cells, which may play an important role in tumor evasion.更多还原