UV-induced immunosuppressive and anti-inflammatory actions: mechanisms and clinical applications.
The introduction in 1974 of psoralens UVA (PUVA) therapy followed in 1987 by extracorporeal photopheresis (ECP) has launched UV light in medicine field. A significant number of potential mechanisms could be linked to the basic cellular UV action (i.e., DNA damage and subsequent cells apoptosis). Phagocytosis by macrophages and dendritic cells (DCs) leads, through a receptor-mediated process, to their modulation. A state of antigen-specific tolerance is induced by induction of Treg cells, inhibition of DCs, which remain at a an immature state, inhibition of production of the proinflammatory cytokines IL-2, IFN-gamma, TNF-alpha and IL-12, and induction of production of cytokines IL-10, TGF-beta and IL-1Ra. Beside cutaneous T-cell lymphoma, use of ECP remains experimental except for graft-versus-host disease, especially the chronic-resistant form. The sparing action of corticosteroids as described in studies on transplantation deserves further attention.
Dupont
Etienne
E
Department of Immunology, Hematology & Transfusion, Erasme Hospital, Brussels, Belgium.
Craciun
Ligia
L
D000818:Animals; D000893:Anti-Inflammatory Agents; D017209:Apoptosis; D004249:DNA Damage; D006084:Graft Rejection; D006801:Humans; D007165:Immunosuppression Therapy; D008262:Macrophage Activation; D016377:Organ Transplantation; D011701:PUVA Therapy; D050378:T-Lymphocytes, Regulatory / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D014466:Ultraviolet Rays
D000893:Anti-Inflammatory Agents