[Cell therapy product (Dermagen) for treatment of hard-to-heal skin wounds].

Epidermal sheets were developed for the treatment of hard-to-heal skin wounds. Products currently marketed in France, e.g. Epibase, are very efficient but not totally satisfactory in cases of very deep dermal injury which often occurs in burn victims. A function dermis or "dermis equivalent" association a three-dimensional matrix (dermal substrate) and allogenic dermal fibroblasts able to secrete numerous cytokines, growth factors, and protease inhibitors, was developed in our biotechnology laboratory using good manufacturing standards (ISO9000). This cell therapy product which is histologically and physiologically close to normal dermis is obtained after culturing fibroblasts obtained from a microbiologically and virologically validated cell bank for 21 days in a patented collagenous sponge. Our laboratories successfully developed a freezing process allowing preservation of the product at -80 C. This allows us to perform high-performance quality control of the batches. The product is easy to use and instructions can be described in a few lines. When clinicians order one or more Dermagen sheets, depending on the wound area to treat, Dermagen is thawed and culturel at 37 C for 48 to 72 hours. Metabolic activity is recovered and the product is then packaged in a specific blister with a semi-solid medium to ensure good viability during transportation. In some indications, Dermagen acts like a true transplant and in others like a biological dressing secreting numerous mediators such as growth factors or matrix proteins.