The Alterations of Keratinocyte Surface and Basement Membrane Markers by Treatment with 8-methoxypsoralen Plus Long-wave Ultraviolet Light

The alterations of keratinocyte surface and basement membrane markers by treatment with 8-methoxypsoralen (8-MOP) plus long-wave ultraviolet (UVA) light (PUVA) were examined in guinea pig skin using immunofluorescence (IF) microscopy. Following a single PUVA treatment (UVA doses: 1.8 - 7.2 J/cm2), reactivity with pemphigus and pemphigoid sera, rabbit anti-guinea pig epidermal cell serum, and fluorescein-conjugated concanavalin A was decreased in intensity in a dose-dependent fashion. Fluorescence became distinctly less pronounced by day 2 postirradiation and recovered between days 6-10. IF with rabbit antiglomerular basement membrane antibodies, which cross-reacted with the basement membrane of the skin, apparently was unaltered within this energy dose range. 8-MOP or UVA alone did not change the reactivity with any reagent. These results suggest that PUVA treatment affects keratinocyte membrane markers and pemphigoid antigens but not some of the basement membrane antigens.