title: CD8+ IL-17-producing T cells are important in effector functions for the elicitation of contact hypersensitivity responses.
abstract: Allergen-induced contact hypersensitivity (CHS) is a T cell-mediated delayed-type immune response which has been considered to be primarily mediated by CD8+ T cytotoxic type I (Tc1) cells. IFN-gamma, the prototype Tc1 (Th1) cytokine, has been implicated as the primary inflammatory cytokine for CHS. In this study, we demonstrate that neutralization of IL-17 rather than IFN-gamma suppresses the elicitation of CHS. The suppression does not result from inhibition of the proliferation of allergen-activated T cells. Allergen sensitization induces the development of distinct CD8+ T cell subpopulations that produce IFN-gamma or IL-17. Although CD8+ IL-17-producing cells are stimulated by IL-23, they are inhibited by IL-12, a prototypical stimulator of IFN-gamma-producing Tc1 cells. This indicates that CD8+ IL-17-producing cells are distinct from Tc1 cells and are important in effector functions at the elicitation of CHS. These studies provide insights into a novel mechanism for CHS.
authors.affiliation: Department of Dermatology, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
authors.forename: Donggou
authors.initials: D
authors.lastname: He
authors.forename: Lizhi
authors.initials: L
authors.lastname: Wu
authors.forename: Hee Kyung
authors.initials: HK
authors.lastname: Kim
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.forename: Craig A
authors.initials: CA
authors.lastname: Elmets
authors.forename: Hui
authors.initials: H
authors.lastname: Xu
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism*; D002464:Cell Migration Inhibition; D003877:Dermatitis, Contact / Q000276:immunology* / Q000473:pathology / Q000517:prevention & control; D004487:Edema / Q000276:immunology / Q000473:pathology / Q000628:therapy; D005260:Female; D006241:Haptens / Q000008:administration & dosage / Q000276:immunology; D007114:Immunization; D007371:Interferon-gamma / Q000096:biosynthesis; D020381:Interleukin-17 / Q000037:antagonists & inhibitors / Q000096:biosynthesis* / Q000276:immunology; D007962:Leukocytes / Q000276:immunology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D012867:Skin / Q000276:immunology / Q000473:pathology; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism*
chemical_list: D000911:Antibodies, Monoclonal; D006241:Haptens; D020381:Interleukin-17; D007371:Interferon-gamma