title: The role of IL-33 in gut mucosal inflammation.
abstract: Interleukin (IL)-33 is a recently identified cytokine belonging to the IL-1 family that is widely expressed throughout the body and has the ability to induce Th2 immune responses. In addition, IL-33 plays a key role in promoting host defenses against parasites through the expansion of a novel population of innate lymphoid cells. In recent years, a growing body of evidence has shown that the proinflammatory properties displayed by IL-33 are detrimental in several experimental models of inflammation; in others, however, IL-33 appears to have protective functions. In 2010, four different research groups consistently described the upregulation of IL-33 in patients with inflammatory bowel disease (IBD). Animal models of IBD were subsequently utilized in order to mechanistically determine the precise role of IL-33 in chronic intestinal inflammation, without, however, reaching conclusive evidence demonstrating whether IL-33 is pathogenic or protective. Indeed, data generated from these studies suggest that IL-33 may possess dichotomous functions, enhancing inflammatory responses on one hand and promoting epithelial integrity on the other. This review focuses on the available data regarding IL-33/ST2 in the physiological and inflammatory states of the gut in order to speculate on the possible roles of this novel IL-1 family member in intestinal inflammation.
authors.affiliation: Department of Pathology, Case Western Reserve University School of Medicine, Cleveland, OH 44106, USA. luca.pastorelli@me.com
authors.forename: Luca
authors.initials: L
authors.lastname: Pastorelli
authors.forename: Carlo
authors.initials: C
authors.lastname: De Salvo
authors.forename: Maurizio
authors.initials: M
authors.lastname: Vecchi
authors.forename: Theresa T
authors.initials: TT
authors.lastname: Pizarro
mesh_terms: D000818:Animals; D041981:Gastrointestinal Tract / Q000276:immunology* / Q000378:metabolism*; D006801:Humans; D007249:Inflammation / Q000378:metabolism*; D015212:Inflammatory Bowel Diseases / Q000276:immunology / Q000378:metabolism; D007378:Interleukins / Q000235:genetics / Q000378:metabolism*; D007413:Intestinal Mucosa / Q000276:immunology* / Q000378:metabolism*
chemical_list: D007378:Interleukins