Immunobiology of epithelial chemokines in the intestinal mucosa

Epithelial cells lining the gastrointestinal mucosal surface comprise a dynamic physical barrier and coordinate an array of host defense mechanisms to prevent or limit entry of luminal microbes, microbial byproducts, or food-borne and water-borne antigens. Regulated production of a repetoire of inducible/inflammatory and constitutive/homeostatic chemokines by the intestinal epithelium orchestrates and coordinates trafficking of mucosal inflammatory and immune effector cells. Enterocyte-derived chemokines likely play a major role in regulating leukocyte migration in chronic dysregulated inflammation characteristic of IBD and during infection with microbial pathogens (Fig). Further studies of epithelial chemokines and their receptors will continue to decipher the function of these important molecules in mucosal host defense and may lead to development of novel therapeutic strategies for the treatment of gastrointestinal diseases.