Klausner, M., P. Neal, and J. Kubilus. Initial Results with Epi-201, A Developing In Vitro Model of Human Epidermis. J. Invest. Dermatol. 1998. 110(4):558, Abst.#513. [Reprinted by permission of Blackwell Science, Inc.]

retinoic acid - 00302-79-4; ascorbic acid - 00050-81-7; Triton X-100 - 09002-93-1

EPI-201 is a stratified culture of proliferating and differentiating human keratinocytes which has the potential to develop into a state-of-the-art, fully keratinized model of human epidermis (EpiDermÔ ). This development is sensitive to conditions of culture and affords a means to study the effects of pharmacological agents, growth factors, temperature, pH, nutritional additives, and other culture parameters on epidermal differentiation. In the present study, when 10 ng/ml of epidermal growth factor (EGF) is supplied to EPI-201, the resulting tissue contains a granular layer which is thicker and more heavily populated with keratohyalin granules compared to standard EpiDerm. The deletion of EGF yields a thinner tissue with a decreased number granule-containing cells, although cornified cells are present. Retinoic acid (RA) at 1.5 X 10^-8 M induces a structure with large intercellular spaces between the basal and upper layers and causes the swelling of spinous cells. These effects are decreased at lower RA levels and are absent at 5 X 10^-10 M. Ascorbic acid (50 ug/ml), thought to improve ceramide synthesis and promote barrier development, produces tissue which has increased resistance to the action of a common surfactant, Triton X-100. These observations suggest that EPI-201 may be useful in studies of re-epithelialization, wound healing, and normal barrier development.