title: Alloantigen-specific prolongation of allograft survival in recipient mice treated by alloantigen immunization following ultraviolet-B irradiation.
abstract: It is well documented that ultraviolet (UV) radiation present in sunlight suppresses immune responses. However, the majority of studies documenting the immunosuppressive effects of UV irradiation have been carried out in animals exposed to UV irradiation before immunization. Here, we report that recipient mice exposed to UV irradiation 7 days after immunization with a donor alloantigen exhibited prolongation of allograft survival in an alloantigen-specific manner. Recipient mice (H-2(b)) intravenously immunized with 2 x 10(7) allogeneic spleen cells (H-2(b/d)) 7 days before UV irradiation (40 kJ/m(2)) showed prolonged survival of allografts presenting the alloantigen used for sensitization (H-2(b/d)), but not third-party allografts (H-2(b/k)). Adoptive transfer experiments revealed that CD4(+) T cells in UV-irradiated recipients were responsible for this prolongation. CD4(+) T cells that could transfer the suppression produced large amounts of interleukin (IL)-10, but not IL-4. The effect of UV irradiation on alloantigen-specific immunosuppression was cancelled by administration of an anti-IL-10 monoclonal antibody. These results indicate that UV irradiation given after alloantigen immunization induces alloantigen-specific type 1 regulatory T cell-like regulatory T cells that prolong allograft survival and imply that the difficulties associated with predicting donor-related organ availability in transplantation can be dealt with, given the effectiveness of UV irradiation after immunization.
authors.affiliation: Department of Cellular and Molecular Immunology, Mie University Graduate School of Medicine, 2-174 Edobashi, Tsu City, Mie Prefecture, 514-8507, Japan. horit@kuhp.kyoto-u.ac.jp
authors.forename: Tomohide
authors.initials: T
authors.lastname: Hori
authors.forename: Kagemasa
authors.initials: K
authors.lastname: Kuribayashi
authors.forename: Shinji
authors.initials: S
authors.lastname: Uemoto
authors.forename: Kanako
authors.initials: K
authors.lastname: Saito
authors.forename: Linan
authors.initials: L
authors.lastname: Wang
authors.forename: Mie
authors.initials: M
authors.lastname: Torii
authors.forename: Shintaro
authors.initials: S
authors.lastname: Shibutani
authors.forename: Kentaro
authors.initials: K
authors.lastname: Taniguchi
authors.forename: Shintaro
authors.initials: S
authors.lastname: Yagi
authors.forename: Taku
authors.initials: T
authors.lastname: Iida
authors.forename: Chiduru
authors.initials: C
authors.lastname: Yamamoto
authors.forename: Takuma
authors.initials: T
authors.lastname: Kato
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism; D016207:Cytokines / Q000276:immunology / Q000378:metabolism; D006084:Graft Rejection / Q000517:prevention & control; D006085:Graft Survival / Q000276:immunology*; D007114:Immunization; D007165:Immunosuppression Therapy; D016753:Interleukin-10 / Q000276:immunology*; D007519:Isoantigens / Q000276:immunology*; D051379:Mice; D016038:Skin Transplantation / Q000276:immunology*; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism*; D014184:Transplantation, Homologous / Q000276:immunology*; D014466:Ultraviolet Rays
chemical_list: D000911:Antibodies, Monoclonal; D016207:Cytokines; D007519:Isoantigens; D016753:Interleukin-10