Hair Loss

Genes Dev. 1991;5:714.

Transgenic mice provide new insights into the role of TGF-alpha during epidermal development and differentiation.

Vassar R, Fuchs E.

TGF-alpha controls growth in epidermal cells. snip.. Unexpectedly, the only regions of epidermis especially responsive to TGF-alpha overexpression were those that were normally thick and where hair follicle density was typically low. This included most, if not all, body skin from 2-day- to 2-week-old mice, and ear, footpad, tail, and scrotum skin in adult mice. In these regions, excess TGF-alpha resulted in thicker epidermis and more stunted hair growth. snip.. During both postnatal development and epidermal differentiation, responsiveness to elevated TGF-alpha seemed to correlate with existing EGF receptor levels,... no evidence for TGF-alpha-mediated control of EGF receptor (EGFR) expression. snip... In addition, adult transgenic skin that was still both sensitive to TGF-alpha and subject to mild irritation displayed localized regions of leukocytic infiltration and granular layer loss, characteristics frequently seen in psoriasis in humans. These unusual regional and developmental effects of TGF-alpha suggest a natural role for the growth factor in (1) controlling epidermal thickness during development and differentiation, (2) involvement in papilloma formation, presumably in conjunction with TGF-beta, and (3) involvement in psoriasis, in conjunction with some as yet unidentified secondary stimulus stemming from mild mechanical irritation/bacterial infection.

edited for hair loss blog