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（GeD）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 （Ⅲgroup） 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 inⅢgroup cells after transfecting,and CD55 expression was also inhibited in Ⅳgroup. The cell proliferation and degree of Ca2＋] in ⅠandⅡ groups were increased compared with Ⅲgroup, Ⅳgroup （P 〈0.05 ）, after crosslinking of CD55 and CD59 antibodies,but there was no difference between Ⅰgroup and Ⅱ group. Conclusion： CD59 and CD55 have synergistic effects in signal transduction ofT cell activation.