Interleukin 13 and its role in gut defence and inflammation.

Interleukin 13 (IL-13) is a cytokine of increasing interest to gastroenterologists because of its developing role in ulcerative colitis, eosinophilic oesophagitis (EO) and fibrosis. Recent data show that IL-13 may play an important role in a novel innate immune response since it can be released by signals from an injured or inflamed epithelium, of particular relevance to the gut. Animal models of IL-13-driven inflammation (from asthma to colitis and EO) are being translated to human disease and providing insight into potential strategies for new therapies. In fact, multiple clinical trials using anti-IL-13 drugs are underway in asthma and are being extended to gastrointestinal diseases. This review presents the current knowledge on IL-13 production and function in the gut, including the cells and receptor signalling pathways involved in mediating IL-13 effects, the proposed mechanisms of IL-13 induced gut disease and the many drugs currently being tested that target IL-13 related pathways.