KGF And EGF Signaling Block Hair Follicle Induction And Promote Interfollicular Epidermal Fate In Developing Mouse Skin

The study demonstrated that EGF and KGF signalling inhibited hair follicle formation and promoted interfollicular epidermal fate in developing mouse skin. Receptors for EGF and KGF were downregulated in hair follicle placodes, while their ligands persisted. Increased levels of EGFR ligands (HBEGF and amphiregulin) and the FGFR2(IIIb) receptor ligand KGF in embryonic skin organ culture inhibited follicle formation in a time- and dose-dependent manner. Molecular markers and microarray profiling indicated that KGF and EGF signalling promoted epidermal differentiation over hair follicle fate. The findings suggested that downregulation of these pathways was necessary for hair follicle initiation, revealing a new role for KGF in hair follicle formation in mice.