Wound-initiated hair regeneration by adhesive and shrinkable materials

Although there is a global demand for hair regrowth, particularly among middle-aged and older individuals, an effective hair growth technology has not yet been established ¹ . Hair follicle neogenesis is restricted to the embryonic period, but hair regeneration accompanied by wound healing has been observed under some conditions ^2–4 ; however, the underlying mechanisms are unclear. Herein, we demonstrated that creating a wound without dermal defects effectively induced postneonatal hair follicle neogenesis. Separating the epidermis from the dermis by topical application of adhesive and shrinkable materials to mouse skin promoted epidermal regeneration, followed by new hair follicle formation. Hair follicle regeneration, accompanied by the upregulation of related genes, can be induced in mice, including middle-aged and aged mice, regardless of species, sex, skin location, or age. The cycle of the regenerated hair eventually synchronized with that of the surrounding physiological hairs. Our new hair regeneration technique based on reproduction of epidermis–dermis interactions provides a novel means to treat hair loss, including androgenetic alopecia.