补体调节蛋白CD46对CD4^＋T细胞的免疫调控

Immunoregulation of complement regulatory protein CD46 on CD4^+ T cells

目的:探讨CD46分子对CD4+T细胞的免疫调控作用及其机制。方法:分离人CD4+T淋巴细胞,体外检测CD3、ConA、CD3/CD28、CD3/CD46、CD3/CD28/CD46共刺激对CD4+T细胞的作用效果,并检测其细胞上清液中白细胞介素-2(IL-2)、γ-干扰素(IFN-γ)、白细胞介素-10(IL-10)和转化生长因子-β(TGF-β)的水平。结果:与CD3组或阴性对照组相比,ConA、CD3/CD28、CD3/CD46和CD3/CD28/CD46共刺激后,CD4+T细胞均出现显著增殖反应(P<0.05),而且CD3/CD28/CD46共刺激组的增殖活性较CD3/CD28或CD3/CD46共刺激组显著增高(P<0.05)。CD3/CD28共刺激后,IL-2和IFN-γ水平较阴性对照组和CD3组显著升高(P<0.05),CD3/CD46共刺激后,IL-10和TGF-β水平较阴性对照组、ConA组、CD3组和CD3/CD28共刺激组显著升高(P<0.05)。结论:补体调节蛋白CD46可以诱导CD4+T细胞的增殖反应并产生IL-10和TGF-β,有可能抑制同种移植免疫反应。

Objective To investigate the immunoregulation of complement regulatory protein CD46 on CD4^＋T cells and its mechanism. Methods CD4^＋T cells were isolated from human peripheral blood T lymphocytes by magnetic-activated cell sorting. Then the effect of CD3, ConA, CD3/CD28, CD3/CD46, and CD3/CD28/CD46 costimulation on CD4^＋T cells proliferation and levels of interleukin-2 （IL-2）, γ-interferon （IFN-＇y）, interleukin- 10 （IL-10）, and transforming growth factor-β （TGF-13） in supernatant fluid were detected. Results As compared with CD3 group or negative control group, ConA, CD3/CD28, CD3/CD46, and CD3/CD28/CD46 costimualtion can induce significant proliferation of CD4^＋T cells （P 〈 0.05）, especially in CD3/CD28/CD46 costimualtion group （vs CD3/CD28 or CD3/CD46 consitmulation groups, P 〈 0.05 ）. Levels of IL-2 and IFN-γ were significantly increased in CD3/CD28 eostimulation group than those in CD3 group and negative control group （P 〈 0.05）. Levels of IL-10 and TGF-β were significant increased in CD3/CD46 costimulation group than those in negative control, ConA, CD3, and CD3/CD28 groups （P 〈 0.05）. Conclusion Complement regulatory protein CD46 can induce CD4^＋T cells proliferation and increase IL-10 and TGF-β, and may inhibit allograft immune response.