Mucosal immunity

Advances have been made in understanding specialized aspects of acquired mu cosal immunity and the importance of cross-talk between host innate and acq uired immune responses in host mucosal defense. These advances include eluc idation of a molecular basis for the coordinated trafficking and retention of lymphocytes in intestinal sites, new insights into the possible extrathy mic origin of mucosal T cells in the intestine, and the description of liga nds that may be the targets of intraepithelial T-cell recognition. The past year has witnessed the characterization of an array of regulated epithelia l cell mediators and responses important for host mucosal defense against e nteric microbial pathogens and firmly establishes epithelial cells as an in tegral component of the mucosal immune network Animal models continued to f urther understanding of intestinal inflammatory disease, and studies on tis sue transglutaminase have generated significant new insights into the immun opathogenesis of human celiac disease.