Recent advances in epidermal cell cultures.

Among the many skin culture systems, three have been selected in this short review because of their specific potentials in dermatological research. H. Green cultures newborn human forsekin keratinocytes on a mouse 3T3 feeder layer. Keratinocytes grow and keratinize. The feeder cells release factor(a) which allows serial propagation of keratinocytes to be achieved. The cell yield is further increased by adding epidermal grohth factor. This system has already proved to be a potent tool for the study of keratinization at the molecular level. A. Freeman has described a system in which explants of adult human skin are cultured on the dermal aspect of dead split-thickness pig skin. Keratinocytes can be passaged several times. Their differentiation is remarkable: it includes the production of keratohyaline, membrane coating granules, pemphigus as well as pemphigoid antigens. This system is interesting in the study of epidermal morphogenesis and may be applicable to the treatment of burns. The culture of epidermal cells from adult guinea pig ear in comparison with that of dermal fibroblasts is being used to study the specificity of action of pharmacological compounds on growth and keratinization of epidermal cells. Furthermore, the isolation (and culture) of pure populations of basal cells appears as a promising approach to the study of the mechanisms which moderate epidermal cell proliferation.