Heterogeneity of neural crest-derived melanocytes

Abstract

The majority of melanocytes originate from the neural crest cells (NCC) that migrate, spread on the whole embryo’s body to form elements of the nervous system and skeleton, endocrinal glands, muscles and melanocytes. Human melanocytes differentiate mainly from the cranial and trunk NCC. Although melanocyte development has traditionally been associated with the dorsally migrating trunk NCC, there is evidence that a part of melanocytes arise from cells migrating ventrally. The ventral NCC differentiate into neurons and glia of the ganglia or Schwann cells. It has been suggested that the precursors for Schwann cells differentiate into melanocytes. As melanoblasts travel through the dermis, they multiply, follow the process of differentiation and invade the forming human fetal epidermis up to third month. After birth, melanocytes lose the ability to proliferate, except the hair melanocytes that renew during the hair cycle. The localization of neural crest-derived melanocytes in non-cutaneous places e.g. eye (the choroid and stroma of the iris and the ciliary body), ear (cells of the vestibular organ, cochlear stria vascularis), meninges of the brain, heart seems to indicate that repertoire of melanocyte functions is much wider than we expected e.g. the protection of tissues from potentially harmful factors (e.g. free radicals, binding toxins), storage ions, and anti-inflammatory action.

Melanin Transfer in the Epidermis: The Pursuit of Skin Pigmentation Control Mechanisms

“…Two main types of cells compose the skin epidermis: the keratinocytes, the most abundant cells, which are present in all the layers of the epidermis and produce keratin to protect epithelial cells from mechanical and non-mechanical stress; and melanocytes, which are present at the basal layer of the epidermis and produce the protective pigment melanin [1,2]. Melanocytes are neural crest-derived cells arising from the dermal melanoblast lineage that migrate to the epidermis during embryonic development [3][4][5]. Keratinocytes continuously proliferate, migrate, and differentiate toward the upper layers of the epidermis, forming five layers or strata: stratum basale, stratum spinosum, stratum granulosum, stratum lucidum and stratum corneum [6,7].…”

Melanoblasts Populate the Mouse Choroid Earlier in Development Than Previously Described

“…Melanoblasts (MB) are the embryonic precursors of pigment-producing melanocytes present in the eyes, ears, meninges, heart, and skin. 1 They are thought to arise directly from neural crest cells (NCC) and/or secondarily from other NCC-derived cells, Schwann cell precursors (SCP). Subsequently, MB colonize different body sites as a result of differing signaling molecules.…”

Comparative Study of Δ9-Tetrahydrocannabinol and Cannabidiol on Melanogenesis in Human Epidermal Melanocytes from Different Pigmentation Phototypes: A Pilot Study

“…As the key specialized cells that originate from the neural crest, melanocytes play a critical role in the synthesis of the pigment melanin in the epidermis, iris, hair, ears, brain, and lungs [ 10 , 11 ]. Although melanocytes constitute a minority population in the suprabasal layers of the epidermis, they are capable of extending multiple dendrites that facilitate their contact with multiple keratinocytes; a single melanocyte can make contact with up to 40 keratinocytes [ 12 , 13 ].…”