The Antimicrobial Properties of Melanocytes, Melanosomes and Melanin and the Evolution of Black Skin

✍ Scribed by JAMES A MACKINTOSH

• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 283 KB
• Volume: 211
• Category: Article
• ISSN: 0022-5193
• DOI: 10.1006/jtbi.2001.2331

✦ Synopsis

A biological issue that has not been satisfactorily resolved is the role of melanin in skin and other animal tissues. A hypothesis is outlined here to account for the evolution of black skin and the ubiquity of melanin in vertebrate tissues. Evidence is presented that melanization of skin and other tissues forms an important component of the innate immune defense system. A major function of melanocytes, melanosomes and melanin in skin is to inhibit the proliferation of bacterial, fungal and other parasitic infections of the dermis and epidermis. This function can potentially explain (a) the latitudinal gradient in melanization of human skin; (b) the fact that melanocyte and melanization patterns among di!erent parts of the vertebrate body do not re#ect exposure to radiation; (c) provide a theoretical framework for recent empirical "ndings concerning the antimicrobial activity of melanocytes and melanosomes and their regulation by known mediators of in#ammatory responses.