Cellular fatty acid composition of stratified squamous epithelia after transplantation of ex vivo produced oral mucosa equivalent.

PURPOSE We have fabricated, for clinical application, artificial oral mucosa that totally excludes both heterogenic protein interaction and xenotransplantation. The purpose of this study is to compare the fatty acid composition of cell membrane phospholipids related to post-transplantation epithelial regeneration. MATERIALS AND METHODS Cultured keratinocytes, keratinocytes at 2, 3, 4, and 9 weeks after transplantation, and normal oral keratinocytes were compared by gas chromatography for the composition of 23 fatty acids. The relation between the composition of cell membrane fatty acids, and the glucose metabolism was immunohistochemically analyzed. RESULTS 1. Even after transplantation, cultured keratinocytes retained the same ratio of palmitic acid as that of normal oral keratinocytes. 2. Essential fatty acids decreased markedly in cultured keratinocyte membranes to the same composition as that of normal oral mucosa 2 weeks after transplantation. 3. The percent composition of palmitoleic acid in cultured keratinocytes was significantly higher than that in post-transplanted keratinocytes; it decreased 2 weeks after artificial mucosa transplantation, but became similar to that in 3 weeks thereafter. 4. The entire population of stratified keratinocytes in EVPOME before transplantation expressed GLUT-1 protein. CONCLUSION Our findings suggest that post-artificial mucosa epithelialisation allows keratinocytes to proliferate while consuming palmitic acid, and then diet-provided essential fatty acids induce the keratinocytes to differentiate. Complete clinical epithelialisation of the transplant wound requires 4 weeks; however, within 3 weeks of transplantation, cultured cells of a specific metabolic mechanism change into or are replaced by keratinocytes of a normal metabolic mechanism similar to that of surrounding tissue.