Human melanocytes express functional Toll‐like receptor 4

Abstract

Background: Melanocytes are not simply pigment-producing cells, but produce substances with a range of biological functions including antimicrobial defense. Recent studies suggest that Tolllike receptors (TLRs) play an important role in the cellular response through the recognition of pathogens.

Cultured human melanocytes express functional Toll-like receptors 2–4, 7 and 9

“…It has been reported functionally active LPS receptor proteins TLR4 and CD14 were expressed by human melanocytes [37,38]. However, these reports mainly focused on the role of TLRs in melanogenesis of melanocytes, and they did not focus on the role of TLRs in the context of local innate inflammatory responses in epidermis.…”

Toll-like receptors and dermatology

“…Melanocytes express TLR4 and seem to respond, by matrix metalloproteinase induction, to the corresponding ligands 15 Table 2. summarizes TLR expression in resident skin cells 16,21–24 …”

Repeated ultraviolet irradiation induces the expression of Toll‐like receptor 4, IL‐6, and IL‐10 in neonatal human melanocytes

“…Many studies report TLRs expression and functions in keratinocytes . Human melanocytes are known to express TLR2, TLR3, TLR4, TLR7, and TLR9, but their functions are not known well . Human melanocytes also express the functionally active lipopolysaccharide (LPS) receptor proteins TLR4 and CD14 .…”

“…Prior studies have mainly focused on the roles of TLRs in melanogenesis. Upon activation, the TLR2 and TLR4 pathways increase pigmentation and activate TLR5, while the TLR7 pathway decreases pigmentation in human melanocytes …”