title: IL-17 and IL-22: siblings, not twins.
abstract: T helper (Th) cell subsets secrete cytokines that regulate other immune cells. Interleukin (IL)-17 and IL-22 belong to a new class of cytokines with predominant effects on epithelial cells. Thus, these cytokines are key molecules in several disease processes. IL-17 and IL-22 are released by leukocytes such as Th and natural killer cell populations. Both IL-17 and IL-22 induce an innate immune response in epithelial cells, but their functional spectra are generally distinct. IL-17 induces an inflammatory tissue response and is involved in the pathogenesis of several autoimmune diseases, whereas IL-22 is protective/regenerative. This review juxtaposes IL-17 and IL-22 and describes overlaps and differences regarding their cellular sources, biochemical structure, signaling cascades in target cells, and function.
authors.affiliation: Molecular Immunology, Department of Allergy and Clinical Immunology, National Heart and Lung Institute, Imperial College, London, UK. stefanie.eyerich@lrz.tum.de
authors.forename: Stefanie
authors.initials: S
authors.lastname: Eyerich
authors.forename: Kilian
authors.initials: K
authors.lastname: Eyerich
authors.forename: Andrea
authors.initials: A
authors.lastname: Cavani
authors.forename: Carsten
authors.initials: C
authors.lastname: Schmidt-Weber
mesh_terms: D000818:Animals; D015551:Autoimmunity; D004847:Epithelial Cells / Q000276:immunology / Q000378:metabolism; D006801:Humans; D020381:Interleukin-17 / Q000276:immunology* / Q000378:metabolism; D007378:Interleukins / Q000276:immunology* / Q000378:metabolism; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism; D015398:Signal Transduction; D000097043:Interleukin-22
chemical_list: D020381:Interleukin-17; D007378:Interleukins; D000097043:Interleukin-22