TLR4 and inflammatory response: It is observed that exposure to microbial products, such as LPS, is associated with intestinal chronic inflammation [26]; LPS is the ligand of TLR4; we postulated that the increase in TLR4 expression in the intestinal epithelial cells might exaggerate the responses of intestinal epithelial cells to the stimulus of LPS and thus breached the established endotoxin tolerance.