Eosinophils in the gastrointestinal tract and their role in the pathogenesis of major colorectal disorders

Core Tip

Core tip: Eosinophils are multifunctional granulocytes possessing readily releasable stores of cytotoxic proteins, regulatory cytokines and chemokines in their specific granules. In health eosinophils reside in the gut, exerting homeostatic functions including protective mucosal barrier integrity maintenance and contribution to gut-associated immunity. Eosinophils are important players in inflammatory bowel disease pathogenesis (both Crohn’s disease and ulcerative colitis). These cells are also associated with a favourable prognosis in colorectal cancer, however mechanisms of this association remain obscure. The author presents a comprehensive analysis of the current literature on eosinophils in the gut and highlights the importance of poorly investigated immune responses occurring within colorectal mucus.