title: Effect of nitric oxide on the growth of Chlamydophila pneumoniae.
abstract: Chlamydophila pneumoniae is an important human intracellular pathogen; however, the pathogenesis of C. pneumoniae infection is poorly understood and the immune control mechanism versus host cells is not completely known. The role of the nitric oxide (NO) synthase pathway in inhibiting the ability of C. pneumoniae to infect macrophage J774 cells and the ability of NO to damage isolated C. pneumoniae were investigated. Exposure of infected cultures to recombinant murine gamma interferon (MurIFN-gamma) resulted in increased production of NO and reduced viability. Addition of 2-(N,N-diethylamino)-diazenolase-2-oxide before infection of J774 cells or during chlamydial cultivation released NO, both resulting in a reduction in the viability of C. pneumoniae in a dose-dependent way. These results indicate that immune control of chlamydial growth in murine macrophage cells may trigger a mechanism that includes NO release with effects on the multiplication of the microorganism, thus suggesting that NO may play a role in preventing the systemic spread of Chlamydia.
authors.affiliation: Dept. of Experimental Medicine, Section of Microbiology and Clinical Microbiology, 2nd University of Naples, Via S.M. Di Costantinopoli, 16-80138 Naples, Italy. caterina.romano@unina2.it
authors.forename: Caterina Romano
authors.initials: CR
authors.lastname: Carratelli
authors.forename: Antonietta
authors.initials: A
authors.lastname: Rizzo
authors.forename: Rossella
authors.initials: R
authors.lastname: Paolillo
authors.forename: Maria Rosaria
authors.initials: MR
authors.lastname: Catania
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Catalanotti
authors.forename: Fabio
authors.initials: F
authors.lastname: Rossano
mesh_terms: D000818:Animals; D002460:Cell Line; D016993:Chlamydophila pneumoniae / Q000254:growth & development* / Q000276:immunology; D015169:Colony Count, Microbial; D005021:Ethylamines / Q000494:pharmacology; D007371:Interferon-gamma / Q000494:pharmacology; D008264:Macrophages / Q000382:microbiology*; D051379:Mice; D009569:Nitric Oxide / Q000032:analysis / Q000502:physiology*; D011994:Recombinant Proteins
chemical_list: C510939:2-(N,N-diethlyamino)-diazenolase-2-oxide; D005021:Ethylamines; D011994:Recombinant Proteins; D009569:Nitric Oxide; D007371:Interferon-gamma