Culture of amelanotic melanocytes derived from human fetal hair follicles

Abstract

Human melanocyte stem cells (MSCs) or melanoblasts are not well-investigated owing to the devoid of suitable culture system. Establishing cell lines of MSCs and/or their progenies from human hair follicles will provide a better opportunity to satisfy clinical needs and to enable a deeper understanding of hair-related diseases. In the present study, we cultured melanocytes derived from human fetal hair follicles, perform immunocytochemistry and Fontana Masson staining on them, and employed atomic force microscopy (AFM) and scanning electron microscopy to observe their subtle morphologies. The results show that the cultured melanocytes have a bipolar or tripolar appearance, which obviously differ from cultured epidermal melanocytes. Compared to cells derived from adult human hair follicles, these cells display a high proliferative capability and exhibit a clonal growth behavior. At the second passage, all these cells were positive for immunocytochemical staining with the NKI/beteb monoclonal antibody and Fontana Masson staining. Under AFM, the cells exhibited rounded, oval, triangular, or quadrangular perikarya, from which two or three dendrites arose. The dendritic arbor was not homogeneous but appeared as spindle-shaped dendritic swellings, knob-like processes, without any filopodia arising from the dendrites or the cell body. Without using a feeder layer, we successfully obtained the clonal growth of melanocytes from human fetal HFs, suggesting that the medium was suitable for the growth of MSCs and their progenies.

The Clonal Growth Behavior of Melanocytes Derived From Melanocyte Stem Cells in Glabrous Skin

“…Premature differentiation of bulge MSCs is also observed during physiological hair graying in mice and in humans [11]. Amelanotic MCs (AMMCs) from HFs, which may be MSCs and/or their immediate progenies, were first successfully cultured by Tobin et al [12] and have been confirmed by other research teams [13,14].…”

“…However, we found a special type of melanocyte during the process of cultivating foreskin tissue and conventional MCs. Those cells have a high proliferative capacity, show a clonal growth behavior, and are arranged densely, resembling a school of fishes [13]. Their morphology and characteristics are similar to AMMCs from HFs, but were more immature.…”