超抗原SEB诱导外周血单个核细胞对糖皮质激素抵抗的研究  

SEB superantigen induces steroid resistance in PBMCs

作　　者：王凤玉[1] 周建华[1] 仇丽茹[1] 

机构地区：[1]华中科技大学同济医学院附属同济医院儿科,湖北武汉430030

出　　处：《中国病理生理杂志》2010年第4期781-785,共5页Chinese Journal of Pathophysiology

摘　　要：目的:建立超抗原SEB诱导儿童外周血单个核细胞糖皮质激素抵抗的实验模型,并探讨ERK信号通路在该模型中的作用。方法:分离单个核细胞,经不同浓度SEB刺激,通过检测不同浓度地塞米松下的细胞增殖率和激光共聚焦显微镜观察糖皮质激素受体α(GRα)亚细胞定位构建糖皮质激素抵抗的实验模型,Western blotting检测该模型中T-ERK1/2及p-ERK1/2表达。结果:10-500μg/L的SEB可明显降低PBMCs对DEX的抑制作用的反应性,各剂量间差异无显著。SEB刺激组DEX作用前后GRα均趋向分布于胞浆。ERK抑制剂UO126可增加GRα核内分布。SEB可更早更强地诱导ERK1/2磷酸化。结论:超抗原SEB通过阻碍GRα核转位诱导PBMCs产生糖皮质激素抵抗,其机制可能与ERK信号通路持续活化有关。AIM：To establish a model of staphylococcal enterotoxin B （SEB）-induced steroid resistance in human peripheral blood mononuclear cells （PBMCs）,and to investigate the potential mechanism of SEB superantigen-induced steroid resistance in vitro. METHODS： PBMCs were isolated from normal children blood by Ficoll-Hypaque gradient centrifugation and stimulated with SEB at different concentrations. The proliferation rate of cells was measured by MTT assay. The subcellular localization of glucocorticoid receptor α （GRα） was examined by confocal microscopy. Protein phosphorylation was measured by means of Western blotting. RESULTS： SEB induced steroid resistance in a range of 10-500 μg/L and no significant difference among concentrations was observed. In SEB-stimulated PBMCs,the GRα did not translocate to the nuclear after dexamethasone treatment. ERK inhibitor U0126 significantly attenuated the inhibition of GRα nuclear translocation in SEB-stimulated PBMCs. SEB also induced more rapid and sustained phosphorylation of ERK1/2 in PBMCs. CONCLUSION： This study demonstrates that SEB may contribute to steroid resistance through ERK pathway and is associated with abrogation of GRα nuclear translocation.

关 键 词：ERK通路 超抗原 糖皮质激素抵抗 受体 糖皮质激素 

分 类 号：R363[医药卫生—病理学]