title: Maintenance of distinct melanocyte populations in the interfollicular epidermis.
abstract: Hair follicles and sweat glands are recognized as reservoirs of melanocyte stem cells (MSCs). Unlike differentiated melanocytes, undifferentiated MSCs do not produce melanin. They serve as a source of differentiated melanocytes for the hair follicle and contribute to the interfollicular epidermis upon wounding, exposure to ultraviolet irradiation or in remission from vitiligo, where repigmentation often spreads outwards from the hair follicles. It is unknown whether these observations reflect the normal homoeostatic mechanism of melanocyte renewal or whether unperturbed interfollicular epidermis can maintain a melanocyte population that is independent of the skin's appendages. Here, we show that mouse tail skin lacking appendages does maintain a stable melanocyte number, including a low frequency of amelanotic melanocytes, into adult life. Furthermore, we show that actively cycling differentiated melanocytes are present in postnatal skin, indicating that amelanotic melanocytes are not uniquely relied on for melanocyte homoeostasis.
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.
authors.forename: James D
authors.initials: JD
authors.lastname: Glover
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.
authors.forename: Stefan
authors.initials: S
authors.lastname: Knolle
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.
authors.forename: Kirsty L
authors.initials: KL
authors.lastname: Wells
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.
authors.forename: Dianbo
authors.initials: D
authors.lastname: Liu
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.|MRC Human Genetics Unit, MRC IGMM, Western General Hospital, University of Edinburgh, Edinburgh, UK.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Jackson
authors.affiliation: MRC Human Genetics Unit, MRC IGMM, Western General Hospital, University of Edinburgh, Edinburgh, UK.
authors.forename: Richard L
authors.initials: RL
authors.lastname: Mort
authors.affiliation: The Roslin Institute and Royal (Dick) School of Veterinary Studies, University of Edinburgh, Roslin, UK.
authors.forename: Denis J
authors.initials: DJ
authors.lastname: Headon
mesh_terms: D000818:Animals; D002455:Cell Division; D000078404:Epidermal Cells; D018859:Hair Follicle / Q000166:cytology*; D006801:Humans; D008543:Melanins / Q000096:biosynthesis; D008544:Melanocytes / Q000166:cytology*; D051379:Mice
chemical_list: D008543:Melanins
keywords: epidermis; hair follicle; interfollicular; melanocyte; stem cell
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