CD59、CD55在T细胞活化信号转导中的协同作用

目的:研究糖基磷脂酰肌醇(GPI)锚固蛋白CD59、CD55在脂筏介导T细胞信号转导通路中的协同效应。方法:应用siRNA技术,构建特异性针对CD55与CD59基因的重组载体pSUPER-siCD55,pSUPER-siCD59。实验分为未转染的Jurkat细胞组(Ⅰ组)、转染pSUPER空质粒的Jurkat细胞组(Ⅱ组)、转染pSUPER-siCD59重组质粒的Jurkat细胞组(Ⅲ组)及转染pSUPER-siCD55重组质粒的Jurkat细胞组(Ⅳ组)。RT-PCR检测转染细胞中CD55和CD59基因的表达噻唑蓝(MTT)比色法和激光共聚焦扫描显微镜分别检测CD55与CD59联合作用对4组Jurkat细胞的增殖效应以及细胞内钙离子的变化、结果:稳定转染后,Ⅲ组细胞CD59分子的表达和Ⅳ组细胞CD55分子的表达被成功抑制。Ⅰ组和Ⅱ组细胞CD55与CD59联合作用后增殖能力和钙离子浓度均明显高于Ⅲ组、Ⅳ组(P<0.05),Ⅰ组和Ⅱ组之间无差异结论:CD59和CD55在T细胞活化信号转导通路中存在协同效应。

Synergistic Effects of CD59,CD55 in T Cell Signal Transduction

Objective: To study the synergistic effects of of glycosylphosphatidyl inositol(GPI)-anchored protein CD59、CD55 in lipid raft-mediated T cell signal transduction. Methods: Construct recombinant vector pSUPER-siCD55, pSUPER-siCD59 targeting CD55 and CD59 gene with siRNA technique. Human Jurkat cells were divided into 3 groups: Jurkat cells ( I group) , Jurkat cells transfected with pSUPER plasmid ( Ⅱgroup)、Jurkat cells transfected with pSUPER-CD59siRNA plasmid (Ⅲ group) and Jurkat cells transfected with pSUPER-CD55siRNA plasmid (Ⅳ group). CD59 and CD55 mRNA level was detected by RT-PCR. The cell proliferation activity of the four groups was measured by MTTcolorimetry after crosslinking anti-CD55 mAb and anti-CD59 mAb,The kinetic changes of Ca2+] in T cell endochylema were determined by Laser scanning confocal microscope imaging. Results: CD59 expression was successfully inhibited in Ⅲ group cells after transfecting,and CD55 expression was also inhibited in Ⅳ group. The cell proliferation and degree of Ca2+] in Ⅰ and Ⅱ groups were increased compared with Ⅲ group、Ⅳ group (P <0.05 ), after crosslinking of CD55 and CD59 antibodies,but there was no difference between Ⅰ group and Ⅱ group. Conclusion: CD59 and CD55 have synergistic effects in signal transduction of T cell activation.