Hair follicles are self-renewing structures that cycle and regenerate throughout life and also provide a critical niche for keratinocyte stem cells. The interplay between keratinocytes and the underlying mesenchyme are critical for hair follicle morphogenesis and cycling. Several key developmental pathways are involved in determining follicular keratinocyte fate as well as the differentiation into several distinct cellular layers of the follicle during the growth phase of hair. Studies indicate that follicular keratinocytes are distinct from epidermal keratinocytes in proliferative capacity and CD34 expression. HHFK from ScienCell Research Laboratories are isolated from the human scalp. HHFK are cryopreserved at passage one and delivered frozen. Each vial contains >5 x 105 cells in 1 ml volume. HHFK are characterized by immunofluorescence with antibody specific to cytokeratin-18. HHFK are negative for HIV-1, HBV, HCV, mycoplasma, bacteria, yeast, and fungi. HHFK are guaranteed to further expand for 15 population doublings under the conditions provided by ScienCell Research Laboratories. Recommended Medium It is recommended to use Keratinocyte Medium (KM, Cat. #2101) for culturing HHFK in vitro.