INCREASED SMOOTH-MUSCLE ACTIN, FACTOR XIIIA, AND VIMENTIN-POSITIVE CELLS IN THE PAPILLARY DERMIS OF CARBON-DIOXIDE LASER-DEBRIDED PORCINE SKIN

BACKGROUND. Pulsed carbon dioxide (CO2) laser debridement is now being used as therapy for photodamaged skin. It has been proposed that the long duration of erythema and a tissue scaffold, which results from ti ghtening of the collagen helix induced by the laser heat, may lead to tightening of sagging skin and skin creases of lesser magnitude. METHO DS. Weanling pigs exposed to mild and moderate erythema producing dose s of sulfur mustard (bis-2-chloroethyl sulfide; HD) were treated with the CO2 laser (Tru-Pulse) at 6, 24, and 48 hours after exposure. In ad dition to histologic examination of laser-debrided and nondebrided bio psy specimens obtained at 14 days after exposure, immunohistochemical staining with antibodies to smooth muscle actin, Factor XIIIa, vimenti n, and CD3 was performed. RESULTS. CO2 laser debridement of the HD-exp osed skin resulted in clearing of the cytologic atypia induced by this chemical carcinogen and reduced the inflammatory infiltrate. In addit ion laser debridement resulted in increased numbers of stromal cells w ithin the papillary dermis, which showed immunohistochemical staining for smooth muscle actin, Factor XIIIa, and vimentin. CONCLUSIONS. CO2 laser debridement is effective in clearing the epidermis of cytologica lly damage cells in HD as well as solar-damaged skin. In addition CO2 laser debridement may result in tightening of sagging skill and produc e a decrease in skin creases initially, by inducing increased stromal cells within the papillary dermis, with prominent contractile actin fi laments. The collagen produced by these stromal cells may subsequently maintain these improvements in the photoaged skin. (C) 1997 by the Am erican Society for Dermatologic Surgery, Inc.