Regrowth of Grafted Lower Half of the Hair Follicle

ABSTRACT

We have examined the regenerative capabilities of the human scalp hair follicle after grafting the lower half of the follicle. Twenty-eight of 32 intact whole-hair follicles isolated from the human scalp regenerated hairs when grafted onto the forehead of the same person. Seven of the 15 lower-half follicles regenerated complete hair follicles 8 months after grafting showed that the lower-half follicle implant reconstituted the complete hair follicle. The sebaceous gland was not regenerated, but there was an outgrowth in the sebaceous gland regPark ion. Some grafts formed epithelial cysts. Two years after grafting, the histological examination of the regenerated follicle from the lower-half implant showed that the sebaceous gland was completely regenerated. While an intact follicle shows prominent naked shaft outgPark Park Parkrowth, the sheath grows concomitantly with the shaft in lower-half follicles in culture. If grafted lower-half follicles were located too deep, the regrown sheath could not reach the epidermal layer. In this situation, the formation of an epidermal cyst was likely.