The role of autoimmunity in gastroenterology

Crohn's disease (CD) is an immune-mediated chronic intestinal disorder thought to be the result of an aggressive immune response to a subset of enteric bacteria in a genetically predisposed host. Numerous environmental factors are apparently involved in disease pathogenesis. Impaired ability of CD patients to control the gut microflora is associated with defects in the production of some antibacterial compounds (cryptdins) by epithelial cells. In addition, there are the defects in cytoplasmic NOD-like receptors which are sensing intracellularly localized bacteria in CD patients. These defects together with the failure to induce autophagy lead to lack of bacterial clearance and subsequently to mucosal immunopathology.