title: Low-energy visible light irradiation modulates immune responses induced by epicutaneous sensitization with protein antigen.
abstract: Epicutaneous sensitization has been an important route for protein allergen sensitization in atopic disease. Although the skin is irradiated by sunlight daily, the influence of visible light on epicutaneous sensitization has not been explored. In this study, by using a well-established murine protein-patch model, we show that low-energy visible light (LEVL) irradiation could differentially modulate the predominant Th2 immune response induced by epicutaneous sensitization with protein antigen. When the induced Th2 response was strong, as usually observed in BALB/c mice, LEVL irradiation suppressed the response. In contrast, LEVL irradiation enhanced the weaker Th2 response in C57BL/6 mice. Increased IL-18 and decreased TGF-beta expression in draining lymph nodes after LEVL irradiation was observed in BALB/c mice, but not in C57BL/6 mice. LEVL irradiation also enhanced IL-18 expression in skin and reduced the downregulation of CD24 expression on epidermal Langerhans cells in draining lymph nodes of BALB/c mice. Collectively, these results provide evidence for immunomodulatory effects of LEVL irradiation and will help us develop a useful strategy for prevention of allergen sensitization.
authors.affiliation: Department of Dermatology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei, Taiwan.
authors.forename: Jau-Shiuh
authors.initials: JS
authors.lastname: Chen
authors.forename: Hsien-Ching
authors.initials: HC
authors.lastname: Chiu
authors.forename: Chih-Jung
authors.initials: CJ
authors.lastname: Hsu
authors.forename: Ching-Yi
authors.initials: CY
authors.lastname: Liu
authors.forename: Pei-Chen
authors.initials: PC
authors.lastname: Hsieh
authors.forename: Shi-Chuen
authors.initials: SC
authors.lastname: Miaw
authors.forename: Hsin-Su
authors.initials: HS
authors.lastname: Yu
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Wang
mesh_terms: D000818:Animals; D000941:Antigens / Q000276:immunology*; D051927:CD24 Antigen / Q000032:analysis; D016207:Cytokines / Q000096:biosynthesis; D003713:Dendritic Cells / Q000276:immunology; D005260:Female; D007108:Immune Tolerance; D007801:Langerhans Cells / Q000276:immunology; D008027:Light; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000276:immunology; D012867:Skin / Q000276:immunology* / Q000528:radiation effects*; D018417:Th1 Cells / Q000276:immunology; D018418:Th2 Cells / Q000276:immunology
chemical_list: D000941:Antigens; D051927:CD24 Antigen; D016207:Cytokines; D010047:Ovalbumin