title: Differential in situ expression of IL-17 in skin diseases.
abstract: Interleukin (IL)-17 is a key molecule for epithelial immunity and inflammation.
  
  
  OBJECTIVE
  To quantify IL-17 expression in situ in a large panel of cutaneous diseases. 289 samples of the 30 most common cutaneous infectious, autoimmune, inflammatory and tumor diseases were stained for IL-17 immunohistochemically. IL-17 expression strongly varied between the diseases, but was conserved within each disease. The major cellular sources of IL-17 were T cells and granulocytes. Skin diseases caused by extracellular microbials were infiltrated by many IL-17+ cells, while intracellular infections were scarcely positive for IL-17. While autoimmune diseases were mostly accompanied by IL-17+ T cells, IL-17+ granulocytes were dominant in neutrophilic dermatoses. Cutaneous diseases show a characteristic pattern of IL-17+ cellular infiltrate. These patterns are relevant for the clinician, since therapeutic approaches targeting differentiation of Th17 cells as well as direct targeting of IL-17 are or will become available.
authors.affiliation: Department of Dermatology and Allergy, Technische Universität and Helmholtz Center Munich, Biedersteiner Straße 29, Munich, Germany.
authors.forename: Mattias
authors.initials: M
authors.lastname: Fischer-Stabauer
authors.forename: Alexander
authors.initials: A
authors.lastname: Boehner
authors.forename: Stefanie
authors.initials: S
authors.lastname: Eyerich
authors.forename: Teresa
authors.initials: T
authors.lastname: Carbone
authors.forename: Claudia
authors.initials: C
authors.lastname: Traidl-Hoffmann
authors.forename: Carsten B
authors.initials: CB
authors.lastname: Schmidt-Weber
authors.forename: Andrea
authors.initials: A
authors.lastname: Cavani
authors.forename: Johannes
authors.initials: J
authors.lastname: Ring
authors.forename: Ruediger
authors.initials: R
authors.lastname: Hein
authors.forename: Kilian
authors.initials: K
authors.lastname: Eyerich
mesh_terms: D004804:Eosinophils / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D020381:Interleukin-17 / Q000378:metabolism*; D018655:Lymphocyte Count; D009504:Neutrophils / Q000378:metabolism; D012871:Skin Diseases / Q000276:immunology* / Q000378:metabolism* / Q000473:pathology; D058504:Th17 Cells / Q000378:metabolism*
chemical_list: D020381:Interleukin-17