TREATMENT OF BURNS AND DONOR SITES WITH HUMAN ALLOGENEIC KERATINOCYTES GROWN ON ACELLULAR PIG DERMIS

The absence of a dermal component predisposes cultured epidermal sheet s to instability, contractibility, and makes them difficult to handle. In order to overcome these drawbacks, we developed recombined human/p ig skin (RHPS) composed of human keratinocytes cultured on cell-free p ig dermis. The original intention to prepare a permanent skin substitu te composed of xenodermis and autologous epidermis was not achieved, b ut it has been proved that RHPS can serve as an effective, ready to us e keratinocyte delivery system when applied 'upside-down', i.e. with e pidermal cells facing the wound surface. The keratinocyte layer establ ishes a direct contact with the wound bed, while the dermal layer mech anically protects the wound. Twenty deep dermal burns were grafted wit h RHPS: 13 (65%) healed completely in 4-14 days, three (15%) healed pa rtially and four (20%) did not heal. Of five full thickness burn wound s only one healed after repeated RHPS grafting within 18 days. Thirty- one (100%) donor sites treated with any of the three forms of RHPS, su bconfluent, confluent meshed or confluent unmeshed, healed within 6-8 days compared with 14-18 days in control sites. Seven donor sites (100 %) of immunodeficient patients with prolonged wound healing epithelial ized in 7-10 days under RHPS compared with 32-90 days in areas treated with tulle gras and dry gauze.