title: Suppressive effect of ultraviolet-B-irradiation of epidermal cells on the induction of contact sensitivity.
abstract: Contact sensitivity to trinitrophenyl (TNP) hapten was induced by subcutaneous (s.c.) administration of TNP-modified syngeneic spleen cells or epidermal cells (EC) (TNP-EC). Intraperitoneal (i.p.) inoculation of TNP-EC resulted in a comparable response, whereas i.p. administration of TNP-spleen cells or TNP-modified-ultraviolet (UV)-preirradiated EC (TNP-UV-EC) failed to induce TNP-contact sensitivity responses. The present study investigates the effect of UV-irradiation on the potential of EC for inducing the contact sensitivity response. Exposure of BALB/c mouse EC in vitro to 1600 J/m2 of UV-B before they were modified with TNP had no discernible effect on the Ia-positivity and viability of EC. Coexistence of TNP-UV-EC had no inhibitory effect upon the contact sensitivity response induced by TNP-EC via the i.p. route. The absence of suppressor cell generation was substantiated by the adoptive transfer of spleen cells from mice administered TNP-UV-EC i.p. to normal syngeneic mice. The effect of interleukin 1 (IL-1) or epidermal cell-derived thymocyte-activating factor (ETAF) in restoring the ability of TNP-UV-EC to induce contact sensitivity was examined. IL-1 or ETAF administered along with TNP-spleen cells i.p. induced a potent contact sensitivity response, whereas the same preparations of IL-1 or ETAF were unable to restore the contact sensitivity induction by TNP-UV-EC. The results are discussed in the context of UV-induced cell surface changes of the Langerhans cell population.
mesh_terms: D000818:Animals; D003877:Dermatitis, Contact / Q000276:immunology*; D004817:Epidermis / Q000276:immunology / Q000528:radiation effects*; D005260:Female; D006241:Haptens / Q000276:immunology; D000949:Histocompatibility Antigens Class II / Q000276:immunology; D007375:Interleukin-1 / Q000276:immunology / Q000494:pharmacology; D007801:Langerhans Cells / Q000276:immunology / Q000528:radiation effects*; D051379:Mice; D008807:Mice, Inbred BALB C; D050378:T-Lymphocytes, Regulatory / Q000276:immunology; D014301:Trinitrobenzenes / Q000008:administration & dosage / Q000276:immunology; D014466:Ultraviolet Rays
chemical_list: D006241:Haptens; D000949:Histocompatibility Antigens Class II; D007375:Interleukin-1; D014301:Trinitrobenzenes