title: Neisseria meningitidis pili induce type-IIA phospholipase A2 expression in alveolar macrophages.
abstract: Induction of type-IIA secreted phospholipase A2 (sPLA2-IIA) expression by bacterial components other than lipopolysaccharide has not been previously investigated. Here, we show that exposure of alveolar macrophages (AM) to Neisseria meningitidis or its lipooligosaccharide (LOS) induced sPLA2-IIA synthesis. However, N. meningitidis mutant devoid of LOS did not abolish this effect. In addition, a pili-defective mutant exhibited significantly lower capacity to stimulate sPLA2-IIA synthesis than the wild-type strain. Moreover, pili isolated from a LOS-defective strain induced sPLA2-IIA expression and nuclear factor kappa B (NF-kappaB) activation. These data suggest that pili are potent inducers of sPLA2-IIA expression by AM, through a NF-kappaB-dependent process.
authors.affiliation: Unité de Défense Innée et Inflammation, Inserm E-336, Institut Pasteur, 25 rue du Dr. Roux, 75015 Paris, France. touqui@pasteur.fr
authors.forename: Lhousseine
authors.initials: L
authors.lastname: Touqui
authors.forename: Miguel
authors.initials: M
authors.lastname: Paya
authors.forename: Françoise
authors.initials: F
authors.lastname: Thouron
authors.forename: Annie
authors.initials: A
authors.lastname: Guiyoule
authors.forename: Maria-Leticia
authors.initials: ML
authors.lastname: Zarantonelli
authors.forename: Dominique
authors.initials: D
authors.lastname: Leduc
authors.forename: Yongzheng
authors.initials: Y
authors.lastname: Wu
authors.forename: Muhamed-Kheir
authors.initials: MK
authors.lastname: Taha
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Alonso
mesh_terms: D000818:Animals; D010861:Fimbriae, Bacterial / Q000737:chemistry / Q000378:metabolism*; D006168:Guinea Pigs; D008070:Lipopolysaccharides / Q000302:isolation & purification / Q000378:metabolism*; D016676:Macrophages, Alveolar / Q000201:enzymology*; D016328:NF-kappa B / Q000378:metabolism; D009345:Neisseria meningitidis / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D010741:Phospholipases A / Q000235:genetics / Q000378:metabolism*; D054467:Phospholipases A2
chemical_list: D008070:Lipopolysaccharides; D016328:NF-kappa B; C023023:lipid-linked oligosaccharides; D010741:Phospholipases A; D054467:Phospholipases A2