Blood-group-related carbohydrates are expressed in organotypic cultures of human skin and oral mucosa.

Cellular maturation and migration are usually associated with changes in cell-surface carbohydrates, but the relationship between these changes and cell behaviour is at present largely unknown. To investigate whether an organotypic culture system can be used as an in vitro model to study the function of cell-surface carbohydrates, we established organotypic cultures of skin and buccal mucosa. In these cultures, keratinocytes are grown at the air-liquid interface on a supporting matrix consisting of homologous fibroblasts embedded in a collagen type I gel. We examined the expression of blood-group-related carbohydrate structures, including Lewis x, sialylated Lewis x, Lewis y, Lewis a, and Lewis b, on the surface of epithelial cells in the cultures. We compared the results with the expression of more well-established markers, including cytokeratins, integrins, bullous pemphigoid antigen and laminin, in the same cultures. The organotypic skin and oral mucosa cultures showed a histological differentiation pattern analogous to that of normal skin and buccal mucosa, and a tissue-specific expression of carbohydrate structures and cytokeratins. However, both types of organotypic cultures also expressed markers which are normally seen during wound healing, including Lewis y, cytokeratin 16, and cytokeratin 19. We conclude that the organotypic cultures of oral mucosa and skin are suitable models for future studies of the function of cell-surface carbohydrates, although the expression of wound healing markers has to be taken into consideration.