VALIDATION OF AN IN-VIVO WOUND-HEALING MODEL FOR THE QUANTIFICATION OF PHARMACOLOGICAL EFFECTS ON EPIDERMAL REGENERATION

Background: Non-invasive assessment methods such as measurement of the transepidermal water loss (TEWL) allow a continuous follow-up of cutaneous processes with impairment of the epidermal barrier function. Objective: The aim of the trial was to establish an in vivo model for the assessment of drug effects on epidermal regeneration. Methods: Twenty healthy volunteers were included in this double-blind randomized trial. After setting four suction blisters on the volar aspect of the forearm, the epidermis was removed to create a standardized subepidermal wound. Thereafter the wounds were treated topically for 6 h daily during 14 days. The following treatments were to be compared: a clobetasol 17-propionate preparation under occlusion, a corticoid-free cream under occlusion, no treatment and occlusion (aluminium chamber), no treatment and no occlusion. Daily measurement of TEWL above the wounds was performed. Results: The 0.05% clobetasol 17-propionate preparation caused a dramatic delay in TEWL, decrease, whereby the untreated unoccluded field showed a continuous decrease over the observed period of 14 days. Occlusion and corticoid-free treatment led to a weak but significant delay of TEWL decrease when compared to the untreated unoccluded test field. Conclusion: This model seems to describe re-epithelialization in a reliable manner and can be used for in vivo assessment of drug effects on migrating and proliferating epithelial cells.