Many chemokines including CCL20/MIP-3α display antimicrobial activity

TLDR

Chemokines such as CCL20/MIP‑3α share the CCR6 receptor with β‑defensins and contain surface‑localized positive residues, and roughly two‑thirds of known chemokines can kill microbes in vitro, indicating a potential host‑defense role. The authors screened 30 human chemokines and identified 17 that display in‑vitro antimicrobial activity. CCL20/MIP‑3α kills a broad panel of bacteria and fungi, and the study found 17 additional antimicrobial chemokines, with a positively charged electrostatic patch being a common structural feature among them.

Abstract

Abstract Previous studies have demonstrated that β-defensins exhibit chemotactic activity by sharing the chemokine receptor CCR6 with the CC chemokine ligand CCL20/macrophage-inflammatory protein-3α (MIP-3α). Structural analysis of CCL20/MIP-3α revealed that most of the positively charged residues are concentrated at one area of its topological surface, a characteristic considered to be important for the antimicrobial activity of defensins. Here, we report that similar to defensins, CCL20/MIP-3α has antimicrobial effects on Escherichia coli, Pseudomonas aeruginosa, Moraxella catarrhalis, Streptococcus pyogenes, Enterococcus faecium, Staphylococcus aureus, and Candida albicans. Additionally, by screening a total of 30 human chemokines, we have identified an additional 17 human chemokines, which exhibit antimicrobial activity in vitro. Collectively, about two-thirds of the chemokines investigated so far has the capacity to kill microorganisms in vitro, suggesting that antimicrobial activity may be another host-defense function for certain chemokines. Comparison of the structural characteristics between antimicrobial and nonantimicrobial chemokines suggests that topological formation of a large, positively charged electrostatic patch on the surface of the molecule is likely to be a common structural feature of antimicrobial chemokines.