034 Dermal papilla cells from follicles with various responses to androgens in vivo retain differences in gene expression in culture

Randall VA Department of Biomedical Sciences, University of Bradford, Bradford, BD7 1DP, UK

The mesenchyme derived dermal papilla situated at the base of the hair follicle controls many aspects of hair growth. Dermal papilla cells have now been successfully cultured from many species. Human hair follicles differ from many species in that their size varies dramatically in different parts of the body. In many regions the type of hair produced varies with age. The hairs vary from short, fine nonpigmented vellus hair on the child’s face to the long, thick, pigmented terminal hairs in the male beard. These changes, like balding on the scalp, are produced by androgens and are believed to occur via the dermal papilla. Cultured dermal papilla cells from follicle with different responses to androgens in vivo have been investigated in vitro. Cells from androgen-sensitive follicles such as beard and balding scalp contain specific androgen receptors at higher concentrations than those from control areas. Testosterone metabolism to 5adihydrotestosterone reflected hair growth in 5a-reductase deficiency patients. Androgen-sensitive cells also produced greater (beard) or fewer (balding scalp) mitogenic factors in response to testosterone. Thus, these cells offer a useful in vitro model system for investigating androgen action.