Barrier function of human skin and human reconstructed epidermis.

The present study compares the stratum corneum of human skin and human reconstructed epidermis by histological examination as well as by estimation of water permeability. Measurement of the percutaneous absorption of benzoic acid, testosterone, and hydrocortisone revealed that under the same experimental conditions the reconstructed epidermis on de-epidermized dermis exhibits a barrier function with qualitative properties similar to that of normal skin: water and benzoic acid penetrate more rapidly than testosterone and hydrocortisone. Quantitatively, however, reconstructed epidermis is more permeable than normal human skin. This points to an impaired barrier function of the epidermis reconstructed in vitro.