Beyond the Epidermal-Melanin-Unit: The Human Scalp Anagen Hair Bulb Is Home to Multiple Melanocyte Subpopulations of Variable Melanogenic Capacity
July 2023
anagen hair follicle melanocyte subpopulations c-KIT CD117 MITF SOX10 melanosome markers gp100 Melan-A immature melanocytes melanogenic zone peripheral matrix hair growth phase pigment cells stem cell factor receptor microbeads microphthalmia-associated transcription factor sex-determining region Y-box 10 pigment granules
TLDR The human scalp has different types of pigment cells in hair follicles with varying abilities to produce pigment.
The study "Beyond the Epidermal-Melanin-Unit: The Human Scalp Anagen Hair Bulb Is Home to Multiple Melanocyte Subpopulations of Variable Melanogenic Capacity" explores the diversity of pigment cells in the human scalp anagen hair follicle bulb, traditionally seen as solely focused on pigment production for hair shaft transfer. Using c-KIT/CD117 microbeads, researchers isolated bulbar c-KIT-positive and c-KIT-negative melanocytes. Both subpopulations expressed MITF, but only the c-KIT-positive fraction expressed SOX10. The study identified distinct bulbar melanocyte subpopulations with variable expression of downstream differentiation-associated melanosome markers like gp100 and Melan-A. A second 'immature' SOX10 negative melanocyte population, which was c-KIT/MITF double positive, was found outside of the melanogenic zone in the most peripheral/proximal matrix. The function of these more immature melanocytes in the hair follicle is yet to be determined.
