Effect of UVA and PUVA on alloactivating and antigen-presenting capacity of human epidermal Langerhans cells.
Human epidermal cell suspensions (EC), obtained with a suction blister technique and enzyme digestion, were irradiated with various doses of UVA with (PUVA) or without previous incubation with 8-methoxypsoralen (8-MOP). EC were then cocultured with allogeneic T cells or pulsed with the soluble antigen purified protein derivative of tuberculin (PPD) for 90 min before being cocultured with autologous T cells. While low doses of UVA induced a small but significant increase in the PPD-specific T-cell response, both PUVA and higher doses of UVA induced dose-dependent reductions. The allogeneic T-cell responses were reduced with PUVA, as well as with UVA, in a dose-dependent fashion. PUVA was far more effective than UVA in reducing both allogeneic and antigen-specific T-cell responses. There were no differences between numbers of DR-positive cells in EC before, immediately after or 24 h after PUVA or UVA radiation, and quantitative determination of EC HLA-DR molecules using an indirect radioimmunoassay (RIA) technique did not reveal any difference between PUVA-treated and non-irradiated cells.
D002478:Cells, Cultured; D006684:HLA-DR Antigens / Q000032:analysis; D006801:Humans; D007519:Isoantigens / Q000276:immunology*; D007801:Langerhans Cells / Q000187:drug effects / Q000276:immunology* / Q000528:radiation effects; D008730:Methoxsalen / Q000494:pharmacology; D011701:PUVA Therapy; D013601:T-Lymphocytes / Q000276:immunology*; D014373:Tuberculin / Q000494:pharmacology; D014467:Ultraviolet Therapy
D006684:HLA-DR Antigens; D007519:Isoantigens; D014373:Tuberculin; D008730:Methoxsalen