不同来源的人肠上皮细胞内毒素相关受体的表达  

Expression of lipopolysaccharide-associated receptors in different human intestinal epithelial cells

作　　者：张道杰[1] 蒋建新[2] 陈永华[2] 朱佩芳[2] 

机构地区：[1]济南军区总医院实验诊断科,山东省济南市250031 [2]中国人民解放军第三军医大学大坪医院野战外科研究所第四研究室,重庆市400042

出　　处：《世界华人消化杂志》2004年第9期2099-2102,共4页World Chinese Journal of Digestology

基　　金：国家重点基础研究发展规划资助项目;No.G1999054203创伤;烧伤与复合伤研究国家重点实验室开放课题基金资助项目;NO.200311~~

摘　　要：目的:研究人肠上皮细胞内毒素相关受体的表达规律,探讨其耐受内毒素的分子机制,为炎症性肠病0BD)发病机制的阐明拓宽新的视野和思路. 方法:用核糖核酸酶保护法(RPA)检测原代培养人正常肠上皮细胞(HNIEC)和人小肠上皮细胞株(HIC)内毒素相关受体CD14,Toll样受体4(TLR4)和MD-2 mRNA的表达;用免疫组化法检测人正常小肠黏膜上皮细胞和结肠黏膜上皮细胞CD14,TLR4和MD-2蛋白的表达.以表达TLR4,CD14 和MD-2的人单核细胞系THP1细胞作为阳性对照. 结果:HNIEC CD14、TLR4、MD-2mRNA均呈低表达, HIC CD14,TLR4,MD-2 mRNA均无表达.小肠黏膜上皮细胞和结肠黏膜上皮细胞3种内毒素受体CD14,TLR4, MD-2蛋白均无表达. 结论:肠上皮细胞表面CD14、TLR4和MD-2呈低表达或不表达可能是其耐受内毒素作用的重要分子机制之一.AIM: To investigate the expression of lipopolysaccharide (LPS)-associated receptors-CD14, Toll-like receptor 4 (TLR4) and MD-2 in human intestinal epithelial cells (lECs) and to discuss the molecular mechanism by which lECs tolerated to LPS. METHODS: The expression of CD14, TLR4 and MD-2 mRNA of human normal intestinal epithelial cells (HNIEC) and human intestinal epithelial cell line (HIC) was detected by RNase protection assay (RPA). The expression of CD14, TLR4 and MD-2 proteins on normal human small intestinal and colonic epithelial cells was detected by immunohis-tochemistry, and THP1 cells were used as positive control. RESULTS: HNIEC expressed very low CD14, TLR4 and MD-2 mRNA and HICs did not express them. Neither normal human small intestinal nor colonic epithelial cells expressed TLR4, CD14 and MD2 proteins. CONCLUSION: Low or loss of expression of TLR4, CD14 and MD-2 on lECs may be an important molecular mechanism by which lECs tolerate to lipopolysaccharide, and this will be helpful to understand the pathogenesis of inflammatory bowel disease.

关 键 词：TLR4 CD14 内毒素 MD-2 表达规律 相关受体 肠上皮细胞 RNA 蛋白 分子机制 

分 类 号：R574[医药卫生—消化系统]