特发性血小板减少性紫癜患者血小板对自身淋巴细胞的异常激活

Abnormally activation of lymphocyte by auto-platelet with idiopathic throm bocytopenic purpura

目的 探讨特发性血小板减少性紫癜(ITP)患者血小板表面人类白细胞抗原 (HLA- DR)的表达和CD4+T淋巴细胞的活化状态。方法 采用流式细胞术检测 60例ITP患者和 60例正常人血小板表面HLA DR的表达水平和自身血小板活化的淋巴细胞产生白细胞介素 2(IL -2)水平。结果 ITP患者血小板表面HLA- DR的表达量为 0 .808%±0 .218%,正常对照组为 0. 025%±0. 019%,两者相比差异具有统计学意义(P<0. 01)。ITP患者CD4+T淋巴细胞经自身血小板激活后,IL 2的表达量为 5 .1% ±1 23%,较正常对照组(0 .0% )有明显差异(P<0 .01)。结论 ITP患者在自身血小板HLA DR抗原的作用下,出现了自身反应性T淋巴细胞的异常活化,T淋巴细胞处于高活性状态。

Objective To investigate the expression of HLA DR on the platelet membrane and the activation of CD4 +T lymphocyte with idiopathic thrombocytopenic purpura (ITP) Methods By flow cytometry, HLA DR expressed on platelet membrane and IL 2 level produced by activated CD4 +T lymphocyte in 60 patients with ITP and 60 normal volunteers were measured Results The percentage of platelet expressing HLA DR (0 808±0 218)% measured in 60 patients with ITP by flow cytometry analysis was markedly higher than that in control subjects (0 025±0 019)% ( P <0 01) The IL 2 level produced by activated CD4 +T lymphocyte in 60 patients with ITP (5 1±1 23)% was significantly higher than that in 60 normal volunteers(0 0%)( P <0 01) Conclusion High expressed HLA DR on platelet membrane acts as a kind of auto antigen to activate auto reactive T cells and lead to abnormally enhanced auto immune responses in idiopathic thrombocytopenic purpura