Regulatory role of defensins in inflammatory bowel disease

Defensins are endogenous antimicrobial peptides (AMPs) produced by professional phagocytes, Paneth cells, and epithelial cells at mucosal surfaces, which mediate innate immunity through their potent antimicrobial activity in the intestinal tract. In addition, defensins also regulate the function of diverse host immune cells, thereby play an important role in both innate and adaptive immune responses against pathogenic microbes. Abundant evidences have proved that attenuated changes in defensins expression are observed in inflammatory bowel disease (IBD). Further studies have discovered the concentration of different defensins subgroups has the relationship with various clinical characteristics of IBD and that mucosal surface destruction causes defensins deficiency as a result of inflammatory damage. This article is to review new current approaches on defensins expression in the intestinal mucosa, particularly in IBD and their potential roles in immune responses in the gut mucosa.