肾癌细胞来源的exosomes诱导JurkatT细胞凋亡

Exosomes derived from renal cancer cells induce Jurkat T cell apoptosis in vitro

目的体外研究肾癌786-0细胞来源的exosomes介导肿瘤免疫逃逸的机制。方法采用CCK-8法检测肾癌786-0细胞来源的exosomes对Jurkat T细胞生长的影响,瑞氏-姬姆萨染色检测Jurkat T细胞形态变化,Annexin V-FITC/PI双染色流式细胞术检测Jurkat T细胞凋亡率,ELISA法检测Jurkat T细胞分泌功能,可溶性Fas阻断实验检测exosomes对Jurkat T细胞凋亡率的影响,Western blot检测exosomes中FasL、及Jurkat T细胞caspase、Bax及Bcl-2蛋白的表达。结果肾癌786-0细胞来源的exosomes可抑制Jurkat T细胞生长,10μg/mL exosomes作用于Jurkat T细胞24 h,生长抑制率为(19.64±0.92)%,72 h为(36.24±1.12)%;400μg/mL exosomes作用24 h,生长抑制率为(55.96±1.35)%,72 h为(76.51±1.37)%。Exosomes诱导Jurkat T细胞凋亡,10μg/mL exosomes作用于Jurkat T细胞8 h,凋亡率为(7.31±1.32)%,24 h为(20.19±1.47)%;400μg/mL exosomes作用8 h,凋亡率为(27.28±1.29)%,24 h为(41.72±0.88)%。Exosomes还明显抑制Jurkat T细胞IL-2、IFN-γ、IL-6、IL-10的分泌水平;exosomes高表达FasL,可溶性Fas阻断实验能逆转Jurkat T细胞的凋亡;凋亡诱导过程中caspase-3、caspase-8、caspase-9被激活,Bax/Bcl-2上调。结论肾癌786-0细胞分泌的exosomes能诱导Jurkat T细胞凋亡,介导肿瘤免疫逃逸。

Objective To investigate the underlying mechanism of exosomes derived from renal cancer cell lines 786-0 to mediate tumor immune escape in vitro. Methods CCK-8 assay was used to determine the effects of exosomes on proliferation in Jurkat T cells. Morphological changes were by wright-giemsa staining;flow cytometry with Annexin V-FITC/PI double staining was used to detect the apoptosis;secretion functions of Jurkat T cell were detected by ELISA assay; effects of exosomes on apoptosis of Jurkat T cell were detected by soluble Fas block experiment; effects on the protein expression of FasL, caspase, Bax and Bcl-2 were assessed by Western blot analysis. Results Exosomes could inhibit Jurkat T cell proliferation, 10 μg/mL exosomes act on Jurkat T cell for 24 and 72 h, growth inhibition rate was （19.64±0.92）% and （36.24±1.12）%; while 400 μg/mL exosomes act on it for 24 h and 72 h, growth inhibition rate was （55.96±1.35）% and （76.51±1.37）% respectively. Exosomes could induce Jurkat T cell apoptosis, 10 μg/mL exosomes act on Jurkat T cell for 8 h, apoptosis rate was （7.31±1.32）%, extending this monitoring to 24 h, apoptosis rate was （20.19±1.47）%; while 400 μg/mL exosomes act on it for 8 and 24 h, apoptosis rate was （27.28±1.29）% and （41.72±0.88）% respectively. Exosomes also suppressed IL-2, IFN-γ, IL-6 and IL-10 secretion obviously. FasL was highly expressed in exosomes, soluble Fas block could reverse Jurkat T cell apoptosis. In this course, caspase-3, caspase-8, caspase-9 were activated, and the ratio of Bax/Bcl-2 increased. Conclusion Exosomes could inhibit the growth of Jurkat T cell and induce apoptosis.It could mediate tumor immune escape.