INITIAL CHARACTERIZATION OF AN EPIDERMAL MODEL CONTAINING FUNCTIONAL MELANOCYTES.

A model of the human epidermis, EpiDerm™, cultured from foreskin derived normal human epidermal keratinocytes (NHEK) has been shown to reproduce many of the histological and ultrastructural properties of native epidermis. In an effort to extend the utility and complexity of these cultures, normal human melanocytes (NHM) have recently been incorporated. Both melanocyte free and melanocyte containing cultures utilize serum free media, with the latter being free of tumor promoters known to stimulate the growth of NHM such as 12-0-tetradecaniylphorbol-13-acetate (TPA). Initial histological characterization of the cultures shows the presence of dendritic cells localized in the basal layer of the cultures which stain positive when exposed to l-dopa, a precursor of melanin. UVB exposure of the melanocyte containing cultures shows a consistent increase in viability retention of 5-10% compared with melanocyte free cultures, as monitored using a standard MTT (3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetra-zolium bromide) cytoxicity assay. These results along with others showing normal epidermal structure, biochemistry, and function provide the theoretical basis for use of this model to study melanogenesis, skin pigmentation, and other photobiological effects on skin in vitro.

DC, Dendritic cells, Endpoints, MTT, EpiDerm, MTT, MTT ET-50 tissue viability assay, MTT assay, Melanin, MelanoDerm, Melanocytes, Melanogenesis, Phototoxicity, Sun screens, Tumor(s), UVA, UVB, Ultra-violet radiation (UV), Ultrastructural Characteristics of, Viability