Human Host Defense Peptide LL-37 Prevents Bacterial Biofilm Formation

• DOI: 10.1128/iai.00318-08
• Publication Date: 2008-07-01T00:34:04Z
• Authors: Joerg Overhage; Andrea Campisano; Manjeet Bains; Ellen C. W. Torfs; Bernd H. A. Rehm; Robert E. W. Hancock
• Keywords: Polymyxin B; Cathelicidin; Polymyxin

ABSTRACT The ability to form biofilms is a critical factor in chronic infections by Pseudomonas aeruginosa and has made this bacterium model organism with respect biofilm formation. This study describes new, previously unrecognized role for the human cationic host defense peptide LL-37. In addition its key modulating innate immune response weak antimicrobial activity, LL-37 potently inhibited formation of bacterial vitro. occurred at very low physiologically meaningful concentration 0.5 μg/ml, far below that required kill or inhibit growth (MIC = 64 μg/ml). also affected existing, pregrown P. biofilms. Similar results were obtained using bovine neutrophil indolicidin, but no inhibitory effect on was detected subinhibitory concentrations mouse CRAMP, which shares 67% identity LL-37, polymyxin B, bactenecin homolog Bac2A. Using microarrays follow-up studies, we able demonstrate decreasing attachment cells, stimulating twitching motility, influencing two major quorum sensing systems (Las Rhl), leading downregulation genes essential development.