抗人DR5单克隆抗体诱导Jurkat和U937细胞凋亡的线粒体信号通路

Anti-human DR5 monoclonal antibody induced apoptosis in Jurkat/U937 cell by mitochondrial signal pathway

目的:探讨抗人死亡受体5(Death receptor 5,DR5)单克隆抗体mDRA-6诱导Jurkat和U937细胞凋亡的线粒体信号通路。方法:MTT法检测mDRA-6对Jurkat和U937细胞生长增殖的影响,以及caspase-9、3抑制剂对mDRA-6抑制Jur-kat和U937细胞生长增殖的影响;琼脂糖凝胶电泳检测Jurkat和U937细胞DNA片段化降解;Western blot检测mDRA-6对Jurkat和U937细胞bax、bcl-2、bcl-xl、Cyt c及caspase-9、3的激活改变。结果:mDRA-6呈时间、浓度依赖性地抑制Jurkat和U937细胞的生长增殖,10 mg/L的mDRA-6作用6、8和10小时,Jurkat细胞增殖抑制率分别达59.38%、72.56%和76.28%,U937细胞增殖抑制率分别达38.67%、47.54%和50.59%。琼脂糖凝胶电泳显示,10 mg/L的mDRA-6作用6小时,Jurkat和U937细胞均呈现凋亡细胞特有的DNA梯形条带;Western blot检测结果发现,随着mDRA-6作用时间延长,Jurkat和U937细胞内促凋亡分子bax增多,抗凋亡分子bcl-2及bcl-xl减少,Cyt c释放明显增多,同时caspase-9、caspase-3也显示明显的激活表现。预先使用caspase-9抑制剂孵育细胞1小时,mDRA-6所致Jurkat和U937细胞生长抑制率分别降低了24.36%(t=5.44,P﹤0.01)和20.82%(t=4.29,P﹤0.01),mDRA-6所致Jurkat和U937细胞凋亡率分别降低了32.89%和23.97%。结论:线粒体信号通路激活是抗人死亡受体5(Death receptor 5,DR5)单克隆抗体mDRA-6诱导Jurkat和U937细胞凋亡的途径之一。

Objective：To explore the mitochondrial pathway in the apoptosis of Jurkat and U937 cells induced by anti-human DR5 monoclonal antibody-mDRA-6.Methods：The inhibition and apoptosis of Jurkat and U937 cells after treating with mDRA-6 or/and caspases inhibitors were analyzed using MTT and FITC Annexin V/PI staining.The DNA ladder of Jurkat and U937 cells treated with mDRA-6（10 mg/L） for 6 h was analyzed by 1% agrose gel electrophoresis.The expression of bax,bcl-2,bcl-xl,Cyt c,caspase-9,caspase-3 of Jurkat and U937 cells after treating with mDRA-6 were detected by Western blot,respectively.Results：The proliferation of Jurkat and U937 cell after treating with mDRA-6 was inhibited in dose-dependent and time-dependent manner;DNA fragmentation detection indicated Jurkat and U937 cell apoptosis induced by mDRA-6.When the cells were treated with mDRA-6,analysis by immunoblotting indicated that bax and Cyt c was increased,while bcl-2 and bcl-xl was decreased in time dependent manner,caspases-9 and caspases-3 were activated in Jurkat and U937 cells.Jurkat and U937 cells were incubated with the inhibitors of caspase-9 for one hour,respectively,and then the cells were treated with mDRA-6,Jurkat and U937 cells inhibition induced by mDRA-6 were reduced by 24.36%（t=5.44,P﹤0.01） and 20.82%（t=4.29,P﹤0.01）,Jurkat and U937 cells apoptosis induced by mDRA-6 were reduced by 32.89% and 23.97%,respectively.Conclusion：Anti-human DR5 monoclonal antibody-mDRA-6 induce the apoptosis of Jurkat and U937 cells through involves mitochondrial signal pathway.