2012•The FASEB JournalRequires access
Novel role of the antimicrobial peptide LL37 in the formation and stabilization of neutrophil extracellular traps
Maren von Köckritz‐Blickwede, Ariane Neumann, Lena Völlger, Evelien T.M. Berends, Margo Molhoek, Victor Nizet, Hassan Y. Naim
Open publisher page 1 citations
Abstract
The antimicrobial peptide LL‐37, a member of the cathelicidin family, has been shown to be present in neutrophil extracellular traps (NETs). However, the function of LL‐37 within the NETs is still unknown, since LL‐37 loses its antimicrobial activity when bound to DNA in the NETs. The aim of this study was to explore the role of LL‐37 in NETs using confocal immunofluorescence microscopy. We could demonstrate that NETs treated with LL‐37 were distinctly more resistant to bacterial nuclease degradation as compared to non‐treated NETs. Furthermore LL‐37 was able to induce the formation of NETs by disruption of the nuclear membrane of stimulated human neutrophils. Biochemical assays utilizing a random LL‐37‐fragment library indicated that the ability of LL‐37 to block nuclease activity is based on its cationic character, whereas the NET‐induction is mediated by the hydrophobic character of the peptide. In conclusion, this study demonstrates a novel role of the antimicrobial peptide LL‐37 in host immune defence: the stabilization and induction of NETs.