Dynamics of Hair Follicle Morphogenesis and Skin Homeostasis

The study explored hair follicle biology, focusing on terminal differentiation and hair canal formation, and its link to harlequin ichthyosis (HI), a severe skin disease. It was found that matrix progenitor cells in hair follicles differentiate in early and late phases, with later phases requiring mature dermal papilla and specific signaling pathways. The research identified keratin 79 (K79) expressing cells as crucial for hair canal formation, entering the epidermis before barrier formation. The study also highlighted the expression of the ABCA12 gene in hair canals, which is affected in HI, and developed a mouse model to study the gene's role in skin and hair development. These findings provided insights into hair follicle biology and potential pathways for studying HI pathogenesis.