Effetto della luce visibile (VIS) sulle cellule di Langerhans: tempi di ripopolazione epidermica dopo completa deplezione indotta dal VIS.

Background. It has already been demonstrated that UV light is able to induce antigenic changes in Langherans cells (LC) and the skin LC depletion after single or serial exposures. In a previous study we have shown in human volunteers that visible light (VIS) cause a 70% depletion of human epidermal LC defined by monoclonal antobody (LEU 6) after a VIS dose corresponding to a solar exposure of 2 hours during the summer at our latitude. Besides, we have shown in mice that VIS causes a membrane markers depletion at does of 100 J/cm2 and a complete depletion at a dose of 700 J/cm2. The electron microscopic analysis showed a destruction of these cells. Material and methods. In this study, the time course of the epidermis recolonization after a VIS irradiation of 700 J/cm2 inducing the complete depletion of the epidermis LC, has been analyzed. Balb/c mice were exposed after depilation to the VIS irradiation and the biopsy punch were done each day for 8 days. Results and conclusions. Results show that epidermis LC become to be detectable 48 hours after VIS irradiation and a complete recolonization occurs after 7 days.