自身反应性T淋巴细胞在抗血小板抗体产生中的作用

Positive Effect of Autoreactive T Lymphocyte Cells on the Production of Antiplatelet Antibody

目的探讨自身反应性T淋巴细胞在抗血小板抗体产生中的作用。方法采用亲和层析柱分离血小板膜糖蛋白GPⅡb/Ⅲa,并以此为抗原刺激ITP患者(实验组)和正常人(正常对照组)的单个核细胞,观察单个核细胞的增殖活化情况及IL-6、抗GPⅡb/ⅢaIgG抗体产生水平。结果实验组单个核细胞的增殖数量明显多于正常对照组,且增殖的细胞以T细胞为主,CD4+T细胞略高于对照组,实验组CD28+、CD25+T淋巴细胞均明显高于对照组。在9例增殖的ITP患者单个核细胞培养的上清液中检测到高于正常对照组的IL-6和抗GPⅡb/ⅢaIgG抗体水平,12例ITP患者中3例T淋巴细胞增生不明显,其IL-6和抗GPⅡb/ⅢaIgG抗体水平亦很低,对照组虽然有淋巴细胞的增殖,但在体外培养过程中产生的相应抗体含量极低。结论GPⅡb/Ⅲa抗原刺激增强了抗GPⅡb/ⅢaIgG抗体的产生,对GPb/a自身反应的T淋巴细胞在激活B细胞及抗GPⅡb/Ⅲa IgG抗体的产生中起到了重要作用。

Objective To investigate the effect of autoreactive T lymphocyte cells on the production of antiplatelet antibody. Methods The platelet membrane Ⅱb/Ⅲa was purified from the affinity chromatography of healthy donors. Peripheral blood mononuclear ceils （PBMCs） were isolated from the patients with Immune Thrombocytopenic Purpura （ITP） （experimental group） and the normal people （control group）. The PBMCs were stimulated with the purified GP Ⅱb/Ⅲa. The cell proliferation was monitored and the level of IL6 and anti-GP Ⅱb/Ⅲa IgG were measured. Results The cell proliferation of the experimental group was faster than that of the control group. The T ceils comprised the majority of increased ceils in the experimental group. The CD4^＋T ceils were slightly more in the experimental group than in the control group. The CD28^＋T and CD25^＋ T ceils were significantly more in the experimental group than in control group. More IL-6 and anti-GP Ⅱb/Ⅲa IgG were detected in the nine ITP patients than in the control group. The increase of T cell growth of three of the seven ITP patients was not obvious. The three patients also had low levels of IL6 and anti-GP Ⅱb/Ⅲa IgG. The proliferation of lymphocyte was also observed in the control group. But very low level of anti-GP Ⅱb/Ⅲa IgG antibody was detected in the PBMCs of the control group in vitro. Conclusion Autoreactive T lymphocyte GP Ⅱb/Ⅲa increases the production of anti-GP Ⅱb/Ⅲa IgG antibody. Such increase has a positive effect on the activation of B ceils.