Effects of Epidermal Growth Factor on the Morphology and Patterns of DNA Synthesis in Isolated Human Hair Follicles

The study investigated the effects of epidermal growth factor (EGF) on isolated human hair follicles. It was found that EGF significantly stimulated the elongation of hair follicles but inhibited hair fiber production. Light microscopy revealed that EGF caused thickening and vacuolation in the lower outer root sheath cells and induced upward migration of matrix cells, forming a 'club hair'-like structure. Autoradiography showed that EGF inhibited DNA synthesis in matrix cells but stimulated it in the outer root sheath. The study concluded that EGF might induce a 'catagen-like' effect by disrupting normal proliferation and migration patterns, suggesting that outer root sheath cells could migrate downward under certain conditions.