Lipid composition and barrier function of human skin after grafting onto athymic nude mice

The barrier properties of human epidermis grafted for 1-3 months onto nude mice are compared with normal human skin. Beside penetration studies with tritiated water and measurements of transepidermal water loss (TEWL), we analyzed the epidermal lipids by high-performance thin layer chromatography and evaluated the ultrastructure of the intercorneocyte lipid arrangement by freeze fracture electron microscopy (FFEM). The permeability of human skin for tritiated water and the TEWL exhibit no significant changes after grafting onto nude mice. FFEM analysis showed that grafted epidermis has the same morphological pattern as normal human epidermis. Regular desmosomes and lamellar lipid structures are present. Grafting did not qualitatively affect the lipid composition of human epidermis. Ceramides which contribute largely to the barrier function, have the same distribution profile.