自身免疫性血小板减少症(AITP)是由IgG介导而引起的血小板减少症。在这以前,关于C_3是否参与血小板的破坏还不清楚。基于这点,本文作者测定了血小板结合IgG高的ATP病人的血小板结合C_3的量。并且在体外检查了洗脱下来的抗体使C_3结合于正常人血小板的能力。结果:正常对照组血小板结合IgG及C_3分别为1.8-14.8,0.7-12.1ng/10~6血小板,与文献上报道相符。病人组血小板结合IgG增加,为14.9-167ng/10~6血小板。其中38例(90%)血小板结合C_3增高,为13.0-249ng/10~6;血小板结合IgG与血小板结合C_3 Autoimmune thrombocytopenia (AITP) is an IgG-mediated thrombocytopenia. Before that, it was unclear whether C_3 was involved in the destruction of platelets. Based on this, the authors determined the amount of platelet bound C_3 in patients with elevated platelet-to-IgG IgG. And the ability of the eluted antibody to bind C_3 to normal human platelets was examined in vitro. Results: Platelet-bound IgG and C_3 in normal control group were 1.8-14.8,0.7-12.1ng / 10 ~ 6 platelets respectively, which accorded with the literature. Platelet-bound patients with IgG increased, for the 14.9-167ng / 10 ~ 6 platelets. Among them, 38 cases (90%) had higher platelet bound C_3, which was 13.0-249ng / 10 ~ 6; Platelet-bound IgG and platelet bound C_3