title: Psoriasis vulgaris lesions contain discrete populations of Th1 and Th17 T cells.
abstract: The importance of T helper 17 (Th17) cells in inflammation and autoimmunity is now being appreciated. We analyzed psoriasis skin lesions and peripheral blood for the presence of IL-17-producing T cells. We localized Th17 cells predominantly to the dermis of psoriasis skin lesions, confirmed that IL-17 mRNA increased with disease activity, and demonstrated that IL-17 mRNA expression normalized with cyclosporine therapy. IL-22 mRNA expression mirrored IL-17 and both were downregulated in parallel with keratin 16. Th17 cells are a discrete population, separate from Th1 cells (which are also in psoriasis lesions), and Th2 cells. Our findings suggest that psoriasis is a mixed Th1 and Th17 inflammatory environment. Th17 cells may be proximal regulators of psoriatic skin inflammation, and warrant further attention as therapeutic targets.
authors.affiliation: Laboratory for Investigative Dermatology, The Rockefeller University, New York, New York 10021, USA.
authors.forename: Michelle A
authors.initials: MA
authors.lastname: Lowes
authors.forename: Toyoko
authors.initials: T
authors.lastname: Kikuchi
authors.forename: Judilyn
authors.initials: J
authors.lastname: Fuentes-Duculan
authors.forename: Irma
authors.initials: I
authors.lastname: Cardinale
authors.forename: Lisa C
authors.initials: LC
authors.lastname: Zaba
authors.forename: Asifa S
authors.initials: AS
authors.lastname: Haider
authors.forename: Edward P
authors.initials: EP
authors.lastname: Bowman
authors.forename: James G
authors.initials: JG
authors.lastname: Krueger
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D002478:Cells, Cultured; D016572:Cyclosporine / Q000627:therapeutic use; D020405:Dermis / Q000276:immunology / Q000473:pathology*; D015870:Gene Expression / Q000187:drug effects / Q000276:immunology; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007371:Interferon-gamma / Q000235:genetics; D020381:Interleukin-17 / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007378:Interleukins / Q000235:genetics; D053536:Keratin-16 / Q000235:genetics; D011565:Psoriasis / Q000188:drug therapy / Q000276:immunology* / Q000473:pathology*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D018417:Th1 Cells / Q000145:classification* / Q000276:immunology / Q000473:pathology*; D000097043:Interleukin-22
chemical_list: D000911:Antibodies, Monoclonal; D016572:Cyclosporine; D007166:Immunosuppressive Agents; D007371:Interferon-gamma; D020381:Interleukin-17; D007378:Interleukins; D053536:Keratin-16; D012333:RNA, Messenger; D000097043:Interleukin-22