title: A single sub-erythematous exposure of solar-simulated radiation on the elicitation phase of contact hypersensitivity induces IL-10-producing T-regulatory cells in human skin.
abstract: Solar ultraviolet (UV) radiation has hazardous effects on human health that are, in part, associated with its immunosuppressive effects via the induction of interleukin (IL)-10 production. Although IL-10 is produced by both T helper type 2 (Th2) cells and T-regulatory type 1 (Tr1) cells, the relative contribution of either subset in UV radiation-induced immunosuppression has not been established. Here, we show that T cells isolated from non-treated allergic contact dermatitis (ACD) reactions, 48 h following nickel challenge and propagated for 7-10 days in the presence of IL-2, were mainly CD4(+) and produced IL-10, but little interferon-gamma. A single sub-erythematous solar-simulated radiation (SSR) prior to antigen challenge exposure resulted in a clinical attenuation of the intensity of ACD reactions which was associated with a significant increase in both the magnitude of IL-10 production by skin-infiltrating T cells and the frequency of IL-10-producing Tr1 cells. Skin-infiltrating T cells in SSR-exposed, as well as non-exposed, ACD reactions showed a perturbed T-cell receptor (TCR)-Vbeta repertoire, without overexpression of a particular TCR-Vbeta gene product, indicating the presence of high frequencies of nickel non-specific T cells in ACD reactions. These results show that a single sub-erythematous SSR induces immunosuppression via the cutaneous infiltration of IL-10-producing Tr1, and to a lesser extent, Th2 cells.
authors.affiliation: UMR5810, Faculté de Pharmacie, Montpellier et Département de Dermatologie, CHU, Nîmes, France.
authors.forename: Pierre E
authors.initials: PE
authors.lastname: Stoebner
authors.forename: Massilva
authors.initials: M
authors.lastname: Rahmoun
authors.forename: Christophe
authors.initials: C
authors.lastname: Ferrand
authors.forename: Laurent
authors.initials: L
authors.lastname: Meunier
authors.forename: Hans
authors.initials: H
authors.lastname: Yssel
authors.forename: Jérôme
authors.initials: J
authors.lastname: Pène
mesh_terms: D000328:Adult; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D003877:Dermatitis, Contact / Q000378:metabolism*; D004890:Erythema / Q000378:metabolism*; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D016753:Interleukin-10 / Q000096:biosynthesis*; D008875:Middle Aged; D009532:Nickel; D011874:Radiometry; D013472:Sunlight; D013601:T-Lymphocytes / Q000378:metabolism*; D018418:Th2 Cells; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D016753:Interleukin-10; D009532:Nickel; D007371:Interferon-gamma