title: Toll-like receptor 2 mediates a cutaneous reaction induced by repetitive ultraviolet B irradiation in C57/BL6 mice in vivo.
abstract: Toll-like receptors (TLRs) mediate not only innate immunity against infection and but also sterile inflammation triggered by endogenous molecules. We conducted a comparative study of the different inflammatory responses induced by repetitive ultraviolet (UV) B irradiation in wild-type (WT) and TLR2 knockout (KO) mice, to provide in vivo evidence of the role of TLRs in mediating UVB-induced responses. UVB-induced inflammatory responses were less severe in TLR2 KO mice than in WT mice after 6 weeks of repeated UVB irradiation. UVB-treated TLR2 KO mice displayed less prominent erythema and scaling, and histopathology showed significantly thinner skin and less inflammatory cell infiltration than that in WT mice. UVB-induced expression of heat-shock protein 70 (an endogenous ligand of TLR2) was lower in TLR2 KO mice. Quantitative RT-PCR revealed significantly lower gene expression levels of UVB-induced interleukin (IL)-1β, IL-6 and matrix metalloproteinase (MMP)-13 in TLR2 KO mice. TLR2 KO mice also showed significantly lower protein level expression of UVB-induced IL-1β in ELISA and MMP-13 in Western blots. Our study demonstrated that TLR2 was associated with inflammatory responses to repetitive UVB irradiation in C57/BL6 mice. Moreover, it suggests that the role of TLR2 in the cutaneous response of UV irradiation and in developing new agents for modulating the effects of UV irradiation should be considered.
authors: Department of Dermatology, Seoul National University Boramae Hospital, Seoul, South Korea.
authors: Hyun Sun
authors: HS
authors: Park
authors: Seon Pil
authors: SP
authors: Jin
authors: Youngae
authors: Y
authors: Lee
authors: In Gyung
authors: IG
authors: Oh
authors: Serah
authors: S
authors: Lee
authors: Jung Ho
authors: JH
authors: Kim
authors: Kwang Hyun
authors: KH
authors: Cho
authors: Jin Ho
authors: JH
authors: Chung
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D004307:Dose-Response Relationship, Radiation; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D007249:Inflammation / Q000209:etiology / Q000378:metabolism* / Q000473:pathology; D053583:Interleukin-1beta / Q000378:metabolism; D015850:Interleukin-6 / Q000378:metabolism; D053509:Matrix Metalloproteinase 13 / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D012867:Skin / Q000378:metabolism* / Q000473:pathology / Q000528:radiation effects*; D051195:Toll-Like Receptor 2 / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D018840:HSP70 Heat-Shock Proteins; D053583:Interleukin-1beta; D015850:Interleukin-6; C493486:Tlr2 protein, mouse; D051195:Toll-Like Receptor 2; D053509:Matrix Metalloproteinase 13
keywords: C57/BL6 mouse; inflammation; toll-like receptor 2; ultraviolet