title: Effects of ultraviolet irradiation on surface marker expression by epidermal immunocompetent cells and contact sensitization to dinitrofluorobenzene in mice.
abstract: We studied the effects of ultraviolet (UV) irradiation on murine epidermal Ia-positive Langerhans cells (Ia + LC) and Thy-I-positive dendritic epidermal cells (Thy-I + dEC). We also studied contact hypersensitivity to dinitrofluorobenzene (DNFB) introduced through UV-treated epidermis. C3H/HeN mice were exposed to UVB or 8-methoxypsoralen plus UVA (PUVA). UVB and PUVA treatment led to a dramatic reduction in surface marker expression of both Ia + LC and Thy-I + dEC. High-dose UVB irradiation (360 J/m2) interfered with contact hypersensitivity to DNFB; the density of Ia + LC may thus be related to the sensitizing potential. In contrast, low-dose UVB (120 J/m2) and PUVA treatment had little effect on contact hypersensitivity despite a marked reduction in Ia + LC. The density of Thy-I + dEC appeared not to be associated with contact hypersensitivity. These results suggest that there may be a Langerhans cell density-independent mechanism for the induction of contact hypersensitivity.
mesh_terms: D000818:Animals; D003877:Dermatitis, Contact / Q000139:chemically induced / Q000276:immunology*; D004139:Dinitrofluorobenzene; D004817:Epidermis / Q000276:immunology / Q000528:radiation effects*; D005260:Female; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007121:Immunocompetence / Q000528:radiation effects*; D007801:Langerhans Cells / Q000276:immunology; D051379:Mice; D008815:Mice, Inbred Strains; D014466:Ultraviolet Rays
chemical_list: D000949:Histocompatibility Antigens Class II; D004139:Dinitrofluorobenzene