高表达Foxp3的肺癌细胞抑制人CD4＋T细胞免疫活性

Foxp3 overexpression in lung cancer cells suppresses immune activities of activated CD4^+T cells

目的:研究高表达转录因子Foxp3的肺癌细胞对CD4^+T淋巴细胞的作用。方法:利用脂质体转染法建立稳定高表达Foxp3的NCIH-h Foxp3肺癌细胞株,荧光定量PCR和Western blot检测细胞Foxp3的表达;ELISA法检测NCIHh Foxp3培养上清中IL-8、IL-10表达量的变化;分离并活化CD4^+T淋巴细胞,用含20%NCIH-h Foxp3肿瘤上清的培养基培养,检测CD4^+T淋巴细胞IL-2表达量的变化;将NCIH-h Foxp3与活化的CD4^+T淋巴细胞共培养,MTT评价免疫效应细胞增殖情况;免疫细胞化学法观察NCIH-h Foxp3细胞对活化CD4^+T淋巴细胞黏附作用的抑制。结果:建立高表达Foxp3的NCIHh Foxp3肺癌细胞株,与阴性对照相比,NCIH-h Foxp3细胞培养上清IL-8表达量降低,IL-10表达量升高,NCIH-h Foxp3肿瘤细胞能抑制活化的CD4^+T淋巴细胞IL-2的表达、增殖及浸润。结论:肺癌细胞Foxp3的表达对活化的CD4^+T淋巴细胞有免疫抑制作用,这可能与NCIH-h Foxp3分泌细胞因子IL-8表达量降低,IL-10表达量升高有关。

Objective： To determine the effects of Foxp3-overexpressing lung cancer cells on activated CD4＋ T lymphocyte. Methods ： Stable Foxp3-overexpressing lung cancer cells NCIH-1299, NCIH-hFoxp3, was generated by transfection of NCIH-1299 cells with plasmid pcDNA3-hFoxp3 mediated by Lipofectamine 2000 and by selection with G418,and validated by quantitative PCR and Western blot. The expression levels of IL-8 and IL-10 secreted by NCIH-hFoxp3 and NCIH-control were measured by ELISA. IL-2 secrection by activated human CD4＋T lymphocyte which was tested after stimulation with 20% conditioned medium of NCIH-hFoxp3 and NCIH-control cells. The proliferation of activated human CD4＋ T lymphocytes was assessed by MTT after coculture with NCIH-hFoxp3 cells. The adhesive ability of activated human CD4＋ T lymphocytes was probed with NCIH-hFoxp3 cells by immuno- cytochemistry. Results： Compared with NCIH-control cells, NCIH-hFoxp3 secreted high level of IL-10 and low level of IL-8. NCIH- hFoxp3 with Foxp3 overexpression significantly suppressed the proliferation,adhesive potential and IL-2 expression by activated CD4＋ T cells. Conclusion： Suppression of immune activities of activated CD4＋ T cells by Foxp3 overexpression in lung cancer cells may correlate with cytokine IL-8 and IL-10,which can contribute lung cancer progression.