Pathways of cell specialization of follicular stem cells

It has been proposed that the progeny of hair follicular stem cells of the bulge can undergo two independent pathways of cell migration/ specialization: moving upward they are involved in the long-term maintenance of the epidermis (the bulge epidermal pathway), whereas moving downward during the early anagen of each hair cycle they give rise to the lower, dispensable portion of a new follicle (the bulge follicle pathway).

Involvement of follicular stem cells in forming not only the follicle but also the epidermis. Taylor G, Leher MS, Jensen PJ, Sun T-T, Lavker RM. Cell 102: 451-461, 2000.

Mayumi Ito, Zaixin Yang, Thomas Andl, Chunhua Cui, Noori Kim, Sarah E. Millar & George Cotsarelis

Nature 447, 316-320(17 May 2007)