目的　探讨细胞因子白介素 18(IL 18)对大肠癌细胞Fas配体 (FasL)蛋白表达水平的调控 ,及其对肿瘤细胞反向杀伤T淋巴细胞作用的影响。方法　应用Western蛋白印迹法 ,检测IL 18作用后的人大肠癌SW 6 2 0细胞FasL蛋白表达水平的变化 ;应用流式细胞术分析IL 18处理后肿瘤细胞所诱导的Jurkat淋巴细胞凋亡率的变化。结果　 10 μg/L和 10 0 μg/L两种浓度的IL 18作用 9h后 ,SW6 2 0细胞FasL蛋白开始上调 ,分别于作用 18和 36h后达到峰值 ,持续 72h后 ,FasL表达水平恢复到初始状态。随着FasL表达水平的上调 ,肿瘤细胞所诱导的Jurkat细胞凋亡率上升。结论　细胞因子IL 18具有上调大肠癌细胞FasL蛋白表达水平 ,增强肿瘤细胞反向杀伤T淋巴细胞的作用 Objective To investigate the effect of cytokine interleukin 18 (IL 18) on the expression of Fas ligand (FasL) protein in colorectal cancer cells and its effect on the effect of tumor cell T-lymphocytes. Methods Western blotting was used to detect the change of FasL protein expression in human colon cancer SW 620 cells after IL-18 treatment. Flow cytometry was used to analyze the apoptosis rate of Jurkat lymphocytes induced by IL-18 in tumor cells. Variety. Results After treatment with 10 μg/L and 100 μg/L IL 18 for 9 h, the FasL protein in SW6 2 0 cells was up-regulated and peaked at 18 and 36 h, respectively. After 72 h, the expression of FasL returned to the initial level. status. With the up-regulation of FasL expression, the apoptosis rate of Jurkat cells induced by tumor cells increased. Conclusion The cytokine IL 18 up-regulates the expression of FasL protein in colorectal cancer cells and enhances the effect of tumor cells killing T lymphocytes in the opposite direction.