Friends or Foes? Host defense (antimicrobial) peptides and proteins in human skin diseases

Exp Dermatol. 2017 Nov;26(11):989-998. doi: 10.1111/exd.13314. Epub 2017 Apr 27.

Abstract

Host defense peptides/proteins (HDPs), also known as antimicrobial peptides/proteins (AMPs), are key molecules in the cutaneous innate immune system. AMPs/HDPs historically exhibit broad-spectrum killing activity against bacteria, enveloped viruses, fungi and several parasites. Recently, AMPs/HDPs were shown to have important biological functions, including inducing cell proliferation, migration and differentiation; regulating inflammatory responses; controlling the production of various cytokines/chemokines; promoting wound healing; and improving skin barrier function. Despite the fact that AMPs/HDPs protect our body, several studies have hypothesized that these molecules actively contribute to the pathogenesis of various skin diseases. For example, AMPs/HDPs play crucial roles in the pathological processes of psoriasis, atopic dermatitis, rosacea, acne vulgaris, systemic lupus erythematosus and systemic sclerosis. Thus, AMPs/HDPs may be a double-edged sword, promoting cutaneous immunity while simultaneously initiating the pathogenesis of some skin disorders. This review will describe the most common skin-derived AMPs/HDPs (defensins, cathelicidins, S100 proteins, ribonucleases and dermcidin) and discuss the biology and both the positive and negative aspects of these AMPs/HDPs in skin inflammatory/infectious diseases. Understanding the regulation, functions and mechanisms of AMPs/HDPs may offer new therapeutic opportunities in the treatment of various skin disorders.

Keywords: antimicrobial agent; infection; inflammation; skin immunity; therapeutic agent.

Publication types

  • Review
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antimicrobial Cationic Peptides / immunology*
  • Antimicrobial Cationic Peptides / metabolism*
  • Cathelicidins / immunology
  • Cathelicidins / metabolism
  • Defensins / immunology
  • Defensins / metabolism
  • Humans
  • Immunity, Innate
  • Peptides / immunology
  • Peptides / metabolism
  • Ribonucleases / immunology
  • Ribonucleases / metabolism
  • S100 Proteins / immunology
  • S100 Proteins / metabolism
  • Skin / immunology*
  • Skin / metabolism*
  • Skin Diseases / metabolism*
  • Skin Physiological Phenomena
  • Wound Healing

Substances

  • Antimicrobial Cationic Peptides
  • Cathelicidins
  • Defensins
  • Peptides
  • S100 Proteins
  • dermcidin
  • Ribonucleases
  • Ribonuclease 7