免疫抑制剂对人外周血活化T淋巴细胞凋亡的影响

Apoptosis of activated human peripheral T-lymphocytes and immunosuppressive drugs

目的研究免疫抑制剂霉酚酸(MPA)和环孢素A(CsA)对人外周血活化T淋巴细胞凋亡的影响,并探讨其作用的途径及机理。方法以植物血凝集素M活化人外周血T淋巴细胞,光学显微镜及透射电镜观察细胞凋亡的形态学特征,琼脂糖凝胶电泳检测DNA断裂,流式细胞仪分析细胞膜联蛋白V(AnnexinV)表达。结果MPA作用后,外周血活化T淋巴细胞出现凋亡特征性形态改变和DNA梯形条带,CsA作用后则无此表现。0.1～10mmolL的MPA作用外周血活化T淋巴细胞24、48h,AnnexinV阳性细胞均明显增加(P<0.05或0.01),并呈药物浓度依赖性(r=0.752,P<0.01)和作用时间依赖性(r=0.583,P<0.01);0.1～1mmolLCsA作用外周血活化T淋巴细胞24、48h,AnnexinV阳性细胞均明显减少(均P<0.05)。结论治疗浓度的MPA可诱导人外周血活化T淋巴细胞凋亡,CsA则抑制活化T淋巴细胞凋亡。

Objective To investigate the relationship between apoptosis of activated human T-lymphocytes and immunosuppressive drugs Mycophenolic acid （MPA） and Cyclosporine （CsA）. Methods Human Peripheral T-lymphocytes were activated by phytohemagglutinin （PHA-M） and the activated T-cells were treated with MPA and CsA respectively. Cell morphology was observed microscopically, DNA fragmentation was examined by electmphoresis and the percentage of Annexin V positive cells were measured by flow cytometry respectively. Results Characteristic apoptotic morphology and DNA ladder of activated T-lymphocytes were observed in MPA group, but not in CsA group. Treated with 0.1 - 10mmol/L MPA for 24-48h, the Annexin V positive percentage of activated T-lymphocytes increased significantly （ P〈0.05 ）,and in a close-dependant （ r=0.752, P〈0,01 ）and time-dependant （ r= 0.583, P〈0.01 ）manner. Treated with 0.1-1mmol/L CsA for 24-48h, the Annexin V positive percentage of activated T-lymphocytes decreased significantly （ P〈0.05 ）. Conclusion Clinical relevant doses of immunosuppressive drug MPA can induce apoptosis in activated peripheral T-lymphocytes, but CsA may inhibit apoptosis.