Current concepts in the development of cultured skin replacements.

Current tissue-culture techniques permit the rapid expansion of keratinocyte populations, such that an area of cultured epithelium equivalent to that of the surface of an adult can be obtained from an initial small skin biopsy. Unfortunately, technical obstacles have delayed the widespread clinical use of multilayered sheets of epithelium. These factors include difficulties in preparing and transferring fragile cultured epithelial sheets, as well as frequent unsatisfactory "take" of cultured grafts on the wound bed. As greater understanding of the complex interactions of cells and matrix evolves, so have new techniques in the field of cultured keratinocytes for grafting. We have utilized an animal model that allows us to examine some of these new methods and the factors which influence graft take. It has become clear that adhesion properties of keratinocytes, early delivery of proliferative keratinocytes to the wound, the development of dermal replacements, and improved delivery systems for keratinocytes are important factors which must be considered for the optimal provision of skin replacements.