RT Journal Article SR Electronic(1) A1 Jensen, Peter Ø A1 Bjarnsholt, Thomas A1 Phipps, Richard A1 Rasmussen, Thomas B A1 Calum, Henrik A1 Christoffersen, Lars A1 Moser, Claus A1 Williams, Paul A1 Pressler, Tacjana A1 Givskov, Michael A1 Høiby, NielsYR 2007 T1 Rapid necrotic killing of polymorphonuclear leukocytes is caused by quorum-sensing-controlled production of rhamnolipid by Pseudomonas aeruginosa JF Microbiology, VO 153 IS 5 SP 1329 OP 1338 DO https://doi.org/10.1099/mic.0.2006/003863-0 PB Microbiology Society, SN 1465-2080, AB Quorum sensing (QS) denotes a density-dependent mode of inter-bacterial communication based on signal transmitter molecules. Active QS is present during chronic infections with the opportunistic pathogen Pseudomonas aeruginosa in immunocompromised patients. The authors have previously demonstrated a QS-regulated tolerance of biofilm bacteria to the antimicrobial properties of polymorphonuclear leukocytes (PMNs). The precise QS-regulated effect on the PMNs is, however, unknown. Incubation of human PMNs with supernatants from dense P. aeruginosa cultures showed that the QS-competent P. aeruginosa induced rapid necrosis of the PMNs. This mechanism was also observed in mouse lungs infected with P. aeruginosa, and in sputum obtained from P.-aeruginosa-infected patients with cystic fibrosis. Evidence is presented that the necrotic effect was caused by rhamnolipids, production of which is QS controlled. The results demonstrate the potential of the QS system to facilitate infections with P. aeruginosa by disabling the PMNs, which are a major first line of defence of the host. Furthermore, the study emphasizes the inhibition of QS as a target for the treatment of infections with P. aeruginosa., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/mic.0.2006/003863-0