金黄色葡萄球菌性超抗原诱发银屑病发病机理探讨

目的探讨金黄色葡萄球菌性超抗原诱发银屑病的机制。方法3H-TdR掺入法测定细胞增殖反应，亚二倍体细胞含量测定，片段化DNA分析，膜联蛋白V(AnnexinV)法测定细胞凋亡，流式细胞仪检测细胞表面抗原表达。结果金黄色葡萄球菌肠毒素B活化的淋巴细胞培养上清液作用于角质形成细胞48h，可促进角质形成细胞增殖，诱导角质形成细胞表达HLA-DR和Fas抗原；再次加入上清液继续作用48h，则诱导角质形成细胞凋亡（P<0.01）。结论金黄色葡萄球菌肠毒素B作为超抗原活化T细胞，使之释放细胞因子，后者使角质形成细胞首先活化增殖，继而凋亡。

Study on the Pathogenesis of Psoriasis Induced by Staphylococcal Superantigen

Objective To investigate the pathogenesis of psoriasis induced by staphylococcal superantigen.Methods The proliferation responses of keratinocytes were measured by 3H-TdR incorporation assay.Quantification of hypodiploid cells, analysis of DNA fragmentation, and annexin V method were employed to detect cell apoptosis.The expression of surface antigens on keratinocytes was determined by flow cytometric assay.Results The supernatants of peripheral blood lymphocytes stimulated by staphylococcal enterotoxins B(SEB) could promote the proliferation of keratinocytes and induce the expression of HLA-DR and Fas antigens on keratinocytes after the first 48 h of treatment.Apoptosis of keratinocytes was induced after addition of the same supernatants （ P<0.01） for another 48 h.Conclusions Cytokines released by T lymphocytes activated by SEB, a staphylococcal superantigen, may firstly stimulate the proliferation, and then induce apoptosis of kera tinocytes.