title: Cytokines and mucosal immunity.
abstract: OBJECTIVE
  Cytokines are integral mediators for maintaining intestinal mucosal homeostasis, as well as prominent effector molecules during chronic gut inflammatory diseases. This review focuses on recent studies of the role of specific cytokines in mucosal immunity.
  
  
  RESULTS
  Dichotomous, or even opposing, functions have been described for several cytokines involved in intestinal innate immunity (most notably for members of the interleukin-1 family), which depend on the specific inflammatory conditions within the intestinal mucosa. For example, both interleukin-1α and interleukin-33 exhibit 'alarmin'-type properties that can signal tissue or cell damage, which further add to their well described proinflammatory roles. Costimulatory molecules of the tumor necrosis factor/tumor necrosis factor receptor superfamily, such as TNF-like cytokine 1A and LIGHT, are actively involved in mucosal proinflammatory pathways, but also may exert protection against infectious agents to facilitate recovery from acute inflammation. Finally, innate lymphoid cells are increasingly recognized as important cellular sources of pivotal mucosal cytokines, including the interleukin-23/T helper 17 cytokine, interleukin-22.
  
  
  CONCLUSIONS
  Elucidating the complexity of cytokine signaling within the normal mucosa and during acute and chronic inflammation will be a pivotal step toward understanding the pathogenesis of immune-mediated gut diseases and developing effective therapies to treat them.
authors.affiliation: aAcademic Department of Gastroenterology, Kapodistrian University of Athens, Laikon Hospital, Athens, Greece bDivision of Gastrointestinal and Liver Disease, Case Western Reserve University School of Medicine, Cleveland, Ohio, USA.
authors.forename: Giorgos
authors.initials: G
authors.lastname: Bamias
authors.forename: Kristen O
authors.initials: KO
authors.lastname: Arseneau
authors.forename: Fabio
authors.initials: F
authors.lastname: Cominelli
mesh_terms: D056704:Adaptive Immunity; D016207:Cytokines / Q000276:immunology / Q000378:metabolism*; D006706:Homeostasis / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate; D015212:Inflammatory Bowel Diseases / Q000276:immunology* / Q000503:physiopathology; D053582:Interleukin-1alpha / Q000378:metabolism; D053583:Interleukin-1beta / Q000378:metabolism; D053759:Interleukin-23 / Q000378:metabolism; D000067596:Interleukin-33; D007378:Interleukins / Q000378:metabolism; D007413:Intestinal Mucosa / Q000276:immunology*; D015398:Signal Transduction; D058504:Th17 Cells / Q000276:immunology / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism; D000097043:Interleukin-22
chemical_list: D016207:Cytokines; D053582:Interleukin-1alpha; D053583:Interleukin-1beta; D053759:Interleukin-23; D000067596:Interleukin-33; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D000097043:Interleukin-22; C506536:IL33 protein, human