title: Pseudomonas aeruginosa eradicates Staphylococcus aureus by manipulating the host immunity.
abstract: Young cystic fibrosis (CF) patients' airways are mainly colonized by Staphylococcus aureus, while Pseudomonas aeruginosa predominates in adults. However, the mechanisms behind this infection switch are unclear. Here, we show that levels of type-IIA-secreted phospholipase A2 (sPLA2-IIA, a host enzyme with bactericidal activity) increase in expectorations of CF patients in an age-dependent manner. These levels are sufficient to kill S. aureus, with marginal effects on P. aeruginosa strains. P. aeruginosa laboratory strains and isolates from CF patients induce sPLA2-IIA expression in bronchial epithelial cells from CF patients (these cells are a major source of the enzyme). In an animal model of lung infection, P. aeruginosa induces sPLA2-IIA production that favours S. aureus killing. We suggest that sPLA2-IIA induction by P. aeruginosa contributes to S. aureus eradication in CF airways. Our results indicate that a bacterium can eradicate another bacterium by manipulating the host immunity.
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France [3] Université Pierre et Marie Curie, Cellule Pasteur UPMC, rue du Dr Roux, 75015 Paris, France.
authors.forename: Erwan
authors.initials: E
authors.lastname: Pernet
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Guillemot
authors.affiliation: 1] Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France [2] Service de Pneumologie, Hôpital Cochin, AP-HP, Paris, France.
authors.forename: Pierre-Régis
authors.initials: PR
authors.lastname: Burgel
authors.affiliation: 1] Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France [2] Service de Pneumologie, Hôpital Cochin, AP-HP, Paris, France.
authors.forename: Clémence
authors.initials: C
authors.lastname: Martin
authors.affiliation: Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275 Centre National de la Recherche Scientifique et Université de Nice Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Gérard
authors.initials: G
authors.lastname: Lambeau
authors.affiliation: INSERM U 806, Université René Descartes, CRCM, Service de Pneumo-Pédiatrie, Hôpital Necker-Enfants Malades, 75015 Paris, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Sermet-Gaudelus
authors.affiliation: Institute of Mother and Child, CF Centre, 01211 Warsaw, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Sands
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France.
authors.forename: Dominique
authors.initials: D
authors.lastname: Leduc
authors.affiliation: 1] Université Paris Descartes, Sorbonne Paris Cité, 75006 Paris, France [2] Service de Bactériologie, Hôpital Cochin, Assistance Publique-Hôpitaux de Paris, 75014 Paris, France.
authors.forename: Philippe C
authors.initials: PC
authors.lastname: Morand
authors.affiliation: Institut de Pharmacologie Moléculaire et Cellulaire, UMR 7275 Centre National de la Recherche Scientifique et Université de Nice Sophia Antipolis, 06560 Valbonne, France.
authors.forename: Louise
authors.initials: L
authors.lastname: Jeammet
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Chignard
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France.
authors.forename: Yongzheng
authors.initials: Y
authors.lastname: Wu
authors.affiliation: 1] Unité de défense innée et inflammation, Institut Pasteur, 75015 Paris, France [2] INSERM U874, 75015 Paris, France.
authors.forename: Lhousseine
authors.initials: L
authors.lastname: Touqui
mesh_terms: D036002:ADP Ribose Transferases; D000293:Adolescent; D000328:Adult; D000818:Animals; D001427:Bacterial Toxins; D001980:Bronchi; D002648:Child; D002675:Child, Preschool; D003550:Cystic Fibrosis / Q000201:enzymology / Q000382:microbiology*; D018450:Disease Progression; D004847:Epithelial Cells / Q000201:enzymology*; D054501:Group II Phospholipases A2 / Q000378:metabolism*; D006168:Guinea Pigs; D006801:Humans; D051379:Mice; D011550:Pseudomonas aeruginosa / Q000502:physiology*; D020545:Respiratory Mucosa; D013183:Sputum / Q000201:enzymology*; D013211:Staphylococcus aureus / Q000502:physiology*; D055815:Young Adult
chemical_list: D001427:Bacterial Toxins; D036002:ADP Ribose Transferases; C444820:exoenzyme S; D054501:Group II Phospholipases A2; C516287:PLA2G2A protein, human