Regulation of Toll-like receptor 4-associated MD-2 in intestinal epithelial cells: a comprehensive analysis:

Innate Immunity

Arunan S.Vamadevan¹ 

关键词: MD-2;    Toll-like receptor 4 (TLR4);    intestinal epithelial cells;    lipopolysaccharide;    methylation;    histone de-acetylation;   

DOI  :  10.1177/1753425909339231

学科分类：生物科学（综合）

来源: Sage Journals

【 摘 要 】

The intestinal epithelium maintains a state of controlled inflammation despite continuous contact with Gram-negative commensal bacteria and lipopolysaccharide (LPS) on its luminal surface. Recognition of LPS by the Toll-like receptor (TLR) 4/MD-2 complex results in pro-inflammatory gene expression and cytokine secretion in intestinal epithelial cells (IECs). We have shown that IECs express low levels of MD-2 and TLR4 and are poorly responsive to LPS. In this study, we did a comprehensive analysis to understand the immune-mediated and epigenetic mechanisms by which IECs down-regulate MD-2 expression. Expression of MD-2 and TLR4 mRNA was examined in human inflammatory bowel disease and intestinal epithelial cell lines (T84, HT-29, Caco-2). Nuclear factor-κB transcriptional activation was used as a measure of LPS responsiveness. Intestinal epithelial cells in patients with inflammatory bowel disease exhibited increased expression of MD-2 and TLR4 mRNA. Lipopolysaccharide responsiveness in IECs was polarized ...

【 授权许可】

CC BY