Dermcidin: a novel human antibiotic peptide secreted by sweat glands

Antimicrobial peptides are an important component of the innate response in many species. Here we describe the isolation of the gene Dermcidin, which encodes an antimicrobial peptide that has a broad spectrum of activity and no homology to other known antimicrobial peptides. This protein was specifi cally and constitutively expressed in the sweat glands, secreted into the s weat and transported to the epidermal surface. In sweat, a proteolytically processed 47-amino acid peptide was generated that showed antimicrobial act ivity in response to a variety of pathogenic microorganisms. The activity o f the peptide was maintained over a broad pH range and in high salt concent rations that resembled the conditions in human sweat. This indicated that s weat plays a role in the regulation of human skin flora through the presenc e of an antimicrobial peptide. This peptide may help limit infection by pot ential pathogens in the first few hours following bacterial colonization.