Nitroglycerin and sucrose permeability as quality markers for reconstructed human epidermis

In order to evaluate the epidermal permeability barrier of in vitro reconstructed epidermis, the penetration of nitroglycerin (NG) and sucrose were measured across human keratinocytes cultured at the air-liquid interface, using de-epidermized dermis (DED) as a substrate. In the presence of reconstructed epidermis on top of DED the penetration rate of sucrose is about 100 times and that of NG 2 times lower, as compared to DED only, indicating that the stratum corneum of the cultured epidermis exhibits considerable barrier capacity. The permeability of reconstructed epidermis was for both solutes higher (3- to 10-fold) than that of freshly excised human skin. Based on the impaired barrier function and distribution of various differentiation markers it can be concluded that the reconstructed human epidermis used in the present study shows a high extent of similarity with hyperproliferating epidermis.