title: Quantitative and morphologic changes of Langerhans' cells after ultraviolet A irradiation of human epidermis.
abstract: Three different surface markers (OKT6, HLA-DR, and adenosinetriphosphatase) were compared to identify Langerhans' cells, and the changes in number and morphology of these cells were studied at different intervals after irradiation of human skin by a 2.5-fold minimal erythema dose of ultraviolet A. Morphologic alteration and decreased surface-marker reactivity became evident on day 2 and were most pronounced on day 3 or day 4 (injury phase). The recovery phase started between day 4 and 1 week and was complete by 3 weeks. HLA-DR+/OKT6- (DR+T6-) cells were present at all time intervals. The ratio of these cells to the sum of DR+T6- and DR+T6+ cells was 0.3% before irradiation, reached a peak of 65.4% at day 4, and decreased to 0.6% by 3 weeks.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000328:Adult; D000954:Antigens, Surface / Q000378:metabolism; D005260:Female; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D007801:Langerhans Cells / Q000473:pathology / Q000528:radiation effects*; D008297:Male; D008856:Microscopy, Fluorescence; D014466:Ultraviolet Rays / Q000009:adverse effects*
chemical_list: D000954:Antigens, Surface; D006684:HLA-DR Antigens; D000251:Adenosine Triphosphatases