Comparative assessment of commercially available wound gels in ex vivo human skin reveals major differences in immune response-modulatory effects.

Wound healing is a crucial process for maintaining the function of human skin as a protective barrier to pathogens and other external stress factors. Hydrogels-in combination with antimicrobials-are often used, as moist wound care has been widely accepted as standard therapy. Recently, we reported about immune response-modulatory effects of an octenidine-based hydrogel, however little is known about the mechanism of action of other hydrogels including antiseptic molecules or chlorine-based and chlorine-releasing agents, respectively. The aim of this study was the comparative assessment of commercially available wound gels (octenilin®, Prontosan®, Lavanid®, Betadona®, ActiMaris®, Microdacyn60®, VeriforteTMmed) with regard to their effects on the secretion of distinct cytokines (IL-6, IL-8, IL-10), matrix-metalloproteinases as well as their potential to cause alterations in skin structure and apoptosis. Hence, tape-stripped human ex vivo skin biopsies were treated topically with wound gels and cultured for 48 h. Enzyme-linked immunosorbent assays and an enzyme activity assay of culture supernatants revealed that octenilin® demonstrates significantly broader anti-inflammatory and protease-inhibitory capacities than other wound gels. Further, haematoxylin & eosin as well as caspase-3 staining of treated biopsies showed that octenilin® does not alter skin morphology and shows the least interfering effect on human epidermal cells compared to untreated controls. Overall, this study clearly demonstrates totally different effects for several commercially available hydrogels in our wound model, which gives also new insight into their tissue compatibility and mode of action.