title: Epidermal CCR6+ γδ T cells are major producers of IL-22 and IL-17 in a murine model of psoriasiform dermatitis.
abstract: Cytokine components of Th17 pathway play vital roles in human psoriasis. Although much is known about TCR αβ T cells in psoriasis, the role of unconventional T cells, including γδ T cells, is unclear. In this study, using an IL-23 skin injection model of psoriasiform dermatitis in mice, we demonstrate that IL-22, IL-17A, and the IL-23R were highly enriched in a population of CCR6(+), TCR γδ-low expressing (GDL) T cells that accumulated in the epidermis after IL-23 injections. GDL cells were distinct from resident TCR γδ-high, Vγ3(+),CCR6(-) T cells in the epidermis that did not change appreciably in numbers following IL-23 injection. Large numbers of CCR6(+) cells were detected at or above the level of the epidermal basement membrane by confocal microscopy 5 d after repeated IL-23 injections at the same time GDL cells increased in numbers in the epidermis. TCR δ-deficient mice (lacking γδ T cells) exhibited decreased ear swelling and downregulated expression of IL-22 and IL-17A in the epidermis following IL-23 injection. Our data suggest that a subset of γδ T cells play a critical role in IL-23-mediated psoriasiform dermatitis.
authors: Department of Dermatology, Medical College of Wisconsin, Milwaukee, WI 53226, USA.
authors: Tomotaka
authors: T
authors: Mabuchi
authors: Tomonori
authors: T
authors: Takekoshi
authors: Sam T
authors: ST
authors: Hwang
mesh_terms: D000818:Animals; D003872:Dermatitis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D004195:Disease Models, Animal; D004817:Epidermis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D020381:Interleukin-17 / Q000096:biosynthesis* / Q000235:genetics; D053759:Interleukin-23 / Q000008:administration & dosage; D007378:Interleukins / Q000096:biosynthesis* / Q000235:genetics; D015603:Keratinocytes / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D051379:Mice; D057507:Mice, 129 Strain; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D011565:Psoriasis / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D012333:RNA, Messenger / Q000096:biosynthesis; D054399:Receptors, CCR6 / Q000096:biosynthesis* / Q000235:genetics; D018123:Receptors, Interleukin / Q000096:biosynthesis / Q000235:genetics; D016176:T-Lymphocyte Subsets / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D058504:Th17 Cells / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D000097043:Interleukin-22
chemical_list: D020381:Interleukin-17; D053759:Interleukin-23; D007378:Interleukins; D012333:RNA, Messenger; D054399:Receptors, CCR6; D018123:Receptors, Interleukin; D000097043:Interleukin-22; C106311:CCR6 protein, human; C498126:CCR6 protein, mouse; C515500:IL23R protein, human; C528688:interleukin-23 receptor, mouse