Ultrastructural studies of cultured human epithelial sheets used as skin allografts.

In this work the ultrastructural features of cultured epithelial sheets (CES) used as skin allografts in humans are described, before and at various times after grafting. Prior to grafting, CES consisted of 4-5 layers of keratinocytes of a low to moderate degree of differentiation. However, after grafting, the CES developed progressively but rapidly features of a well-differentiated epidermis (including melanocytes and Langerhans' cells) and a dermal-epidermal junction. No evidence of rejection was observed. These results demonstrate the key role of normal dermis in the maturation of the surface epithelium and prove the suitability of CES as skin allografts.