[Clinical application of cultured autologous epithelium to donor sites for split-thickness skin graft].

The present study investigated the interaction between the in situ dermis by using the donor site for split-thickness skin graft (STSG) and the cultured autologous epithelium in eleven individuals. Human epithelial cells were cultured according to the method of Rheinwald and Green, with some modification. The mirror-image site was covered by ointment dressing, and used as control. All of the grafted epithelial adhered to the wound bed within 7-8 days, and they were thick enough to be manipulated. On the other hand, the control areas didn't re-epithelize until 13-18th day postoperatively. Pain and exudate were remarkably reduced in all the cases, and there was less itching in 9 cases, as compared to the control areas (P less than 0.01; sign test). Even though there was no visual difference of scarring after 3 months, the grafted areas were much softer than the control areas in 8 cases (P less than 0.01). There was also a definite difference concerning pigmentation decrease in 5 cases. 7 days post-grafting, the cultured epithelium became thicker and more differentiated in 8-10 cell layers, and a well-developed basal lamina was observed by PAS stain and on electron micrographs. A 14th day specimen from the grafted area showed almost normal epidermis with melanin granules in the basal layer, despite of a mild intercellular edema among basal and spinous cells. Biopsies after 3 months revealed that there was less dermal fibrosis in the grafted areas than in the ungrafted ones. There appeared a tendency of rapid healing associated with minimal fibrosis, leading to satisfactory results. It is possible to infer that the epithelial-dermal interaction induced by cultured epithelial autograft may influence and regulate the formation of collagen and other extracellular matrix by fibroblasts. This study suggests that cultured autologous epithelium can provide a successful permanent skin substitutes in the donor site for STSG.