title: Polymorphonuclear leukocytes restrict growth of Pseudomonas aeruginosa in the lungs of cystic fibrosis patients.
abstract: Cystic fibrosis (CF) patients have increased susceptibility to chronic lung infections by Pseudomonas aeruginosa, but the ecophysiology within the CF lung during infections is poorly understood. The aim of this study was to elucidate the in vivo growth physiology of P. aeruginosa within lungs of chronically infected CF patients. A novel, quantitative peptide nucleic acid (PNA) fluorescence in situ hybridization (PNA-FISH)-based method was used to estimate the in vivo growth rates of P. aeruginosa directly in lung tissue samples from CF patients and the growth rates of P. aeruginosa in infected lungs in a mouse model. The growth rate of P. aeruginosa within CF lungs did not correlate with the dimensions of bacterial aggregates but showed an inverse correlation to the concentration of polymorphonuclear leukocytes (PMNs) surrounding the bacteria. A growth-limiting effect on P. aeruginosa by PMNs was also observed in vitro, where this limitation was alleviated in the presence of the alternative electron acceptor nitrate. The finding that P. aeruginosa growth patterns correlate with the number of surrounding PMNs points to a bacteriostatic effect by PMNs via their strong O2 consumption, which slows the growth of P. aeruginosa in infected CF lungs. In support of this, the growth of P. aeruginosa was significantly higher in the respiratory airways than in the conducting airways of mice. These results indicate a complex host-pathogen interaction in chronic P. aeruginosa infection of the CF lung whereby PMNs slow the growth of the bacteria and render them less susceptible to antibiotic treatment while enabling them to persist by anaerobic respiration.
authors.affiliation: Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Kasper N
authors.initials: KN
authors.lastname: Kragh
authors.affiliation: Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Morten
authors.initials: M
authors.lastname: Alhede
authors.affiliation: Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Peter Ø
authors.initials: PØ
authors.lastname: Jensen
authors.affiliation: Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Claus
authors.initials: C
authors.lastname: Moser
authors.affiliation: Department of Public Health, Section of Biostatistics, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Thomas
authors.initials: T
authors.lastname: Scheike
authors.affiliation: Geological Survey of Denmark and Greenland, Copenhagen, Denmark.
authors.forename: Carsten S
authors.initials: CS
authors.lastname: Jacobsen
authors.affiliation: Department of Biomedical Science, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Steen
authors.initials: S
authors.lastname: Seier Poulsen
authors.affiliation: Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Steffen Robert
authors.initials: SR
authors.lastname: Eickhardt-Sørensen
authors.affiliation: Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Hannah
authors.initials: H
authors.lastname: Trøstrup
authors.affiliation: Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Lars
authors.initials: L
authors.lastname: Christoffersen
authors.affiliation: Department of Forensic Medicine, University of Copenhagen, Copenhagen, Denmark.
authors.forename: Hans-Petter
authors.initials: HP
authors.lastname: Hougen
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark.
authors.forename: Lars F
authors.initials: LF
authors.lastname: Rickelt
authors.affiliation: Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark Plant Functional Biology and Climate Change Cluster, University of Technology Sydney, New South Wales, Sydney, Australia Singapore Centre on Environmental Life Science Engineering, School of Biological Science, Nanyang Technological University, Singapore.
authors.forename: Michael
authors.initials: M
authors.lastname: Kühl
authors.affiliation: Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Høiby
authors.affiliation: Department of International Health, Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark tbjarnsholt@sund.ku.dk.
authors.forename: Thomas
authors.initials: T
authors.lastname: Bjarnsholt
mesh_terms: D000328:Adult; D000818:Animals; D018441:Biofilms; D003550:Cystic Fibrosis / Q000276:immunology* / Q000382:microbiology*; D005260:Female; D006801:Humans; D017404:In Situ Hybridization, Fluorescence; D008171:Lung Diseases / Q000276:immunology / Q000382:microbiology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009504:Neutrophils / Q000502:physiology*; D020135:Peptide Nucleic Acids; D011552:Pseudomonas Infections / Q000276:immunology / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000276:immunology*
chemical_list: D020135:Peptide Nucleic Acids
references.citation: J Bacteriol. 2012 Apr;194(8):2062-73
references.pmid: 22343293
references.citation: Respiration. 2000;67(3):239-47
references.pmid: 10867591
references.citation: J Bacteriol. 2003 May;185(9):2687-9
references.pmid: 12700246
references.citation: Microbiol Mol Biol Rev. 1997 Dec;61(4):533-616
references.pmid: 9409151
references.citation: Biotechnol Prog. 1996 May-Jun;12(3):316-21
references.pmid: 8652119
references.citation: J Cyst Fibros. 2013 Sep;12(5):468-74
references.pmid: 23333044
references.citation: J Bacteriol. 2007 Jun;189(12):4449-55
references.pmid: 17400735
references.citation: Int J Oral Sci. 2011 Apr;3(2):55-65
references.pmid: 21485309
references.citation: J Clin Invest. 2002 Feb;109(3):317-25
references.pmid: 11827991
references.citation: Environ Microbiol. 2010 Jun;12(6):1643-58
references.pmid: 20406284
references.citation: Clin Exp Immunol. 2012 Nov;170(2):222-30
references.pmid: 23039893
references.citation: Thorax. 2010 Jan;65(1):57-62
references.pmid: 19846469
references.citation: Trends Microbiol. 2013 Sep;21(9):466-74
references.pmid: 23827084
references.citation: Microbiology (Reading). 2005 Jan;151(Pt 1):75-80
references.pmid: 15632427
references.citation: Annu Rev Microbiol. 1995;49:711-45
references.pmid: 8561477
references.citation: Microbiology (Reading). 2009 Nov;155(Pt 11):3500-3508
references.pmid: 19643762
references.citation: Mol Microbiol. 2007 Jul;65(1):153-65
references.pmid: 17581126
references.citation: J Bacteriol. 2008 Apr;190(8):2767-76
references.pmid: 18156255
references.citation: Antimicrob Agents Chemother. 1991 Sep;35(9):1824-8
references.pmid: 1952852
references.citation: J Immunol. 2013 Jun 15;190(12):6043-50
references.pmid: 23690474
references.citation: Int J Antimicrob Agents. 2010 Apr;35(4):322-32
references.pmid: 20149602
references.citation: J Appl Physiol (1985). 2007 May;102(5):1969-75
references.pmid: 17303703
references.citation: J Clin Invest. 1976 Oct;58(4):989-96
references.pmid: 9426
references.citation: FEBS Lett. 1994 Mar 14;341(1):65-8
references.pmid: 8137924
references.citation: J Cyst Fibros. 2010 Jan;9(1):51-8
references.pmid: 19939747
references.citation: Microbiology (Reading). 2005 Feb;151(Pt 2):373-383
references.pmid: 15699188
references.citation: J Cyst Fibros. 2007 Apr;6(2):101-9
references.pmid: 16844431
references.citation: J Gen Microbiol. 1958 Dec;19(3):592-606
references.pmid: 13611202
references.citation: Inflammation. 1995 Oct;19(5):587-98
references.pmid: 8543373
references.citation: Antimicrob Agents Chemother. 2004 Jul;48(7):2659-64
references.pmid: 15215123
references.citation: Methods Enzymol. 2005;397:166-99
references.pmid: 16260291
references.citation: J Immunol. 2003 Oct 15;171(8):4329-39
references.pmid: 14530358
references.citation: J Clin Invest. 1982 Sep;70(3):550-7
references.pmid: 7107894
references.citation: Am J Respir Crit Care Med. 2007 Apr 15;175(8):822-8
references.pmid: 17234902
references.citation: J Environ Qual. 2013 Jul;42(4):1267-73
references.pmid: 24216378
references.citation: J Antimicrob Chemother. 1991 Feb;27(2):177-84
references.pmid: 1905285
references.citation: Biochem J. 2001 Aug 1;357(Pt 3):593-615
references.pmid: 11463332
references.citation: Dev Cell. 2002 Oct;3(4):593-603
references.pmid: 12408810
references.citation: Infect Immun. 2005 Jan;73(1):444-52
references.pmid: 15618183
references.citation: J Microbiol Methods. 2001 Dec;47(3):281-92
references.pmid: 11714518
references.citation: Pediatr Pulmonol. 2009 Jun;44(6):547-58
references.pmid: 19418571
references.citation: PLoS One. 2014 Jan 17;9(1):e84353
references.pmid: 24465406
references.citation: Nat Rev Microbiol. 2008 Mar;6(3):199-210
references.pmid: 18264116
references.citation: BMC Med. 2011 Apr 04;9:32
references.pmid: 21463524
references.citation: J Bacteriol. 1984 Dec;160(3):928-34
references.pmid: 6438064
references.citation: J Pharmacol Exp Ther. 1996 Jan;276(1):253-7
references.pmid: 8558439
references.citation: APMIS. 2011 Apr;119(4-5):263-74
references.pmid: 21492226
references.citation: FEMS Microbiol Lett. 2004 Jan 15;230(1):13-8
references.pmid: 14734160
references.citation: PLoS One. 2013 Jul 22;8(7):e68484
references.pmid: 23894309
references.citation: Infect Immun. 2007 Nov;75(11):5313-24
references.pmid: 17724070
references.citation: Lancet. 2004 Aug 21-27;364(9435):709-21
references.pmid: 15325838
references.citation: J Bacteriol. 2007 Nov;189(22):8079-87
references.pmid: 17873029