title: Ectopic lymphoid tissue formation in the lungs of mice infected with Chlamydia pneumoniae is associated with epithelial macrophage inflammatory protein-2/CXCL2 expression.
abstract: Infection with Chlamydia pneumoniae (Cp) accounts for around 10% of community acquired bacterial pneumonia and has been associated with other chronic inflammatory conditions. We describe a C57/Bl6 murine model of Cp lung infection characterized by a dose-dependent, resolving neutrophilia followed by lymphocytic infiltration of the lungs. By 21 days post-infection, mice exhibit a T helper type 1 (Th1) polarized serum antibody response with local mucosal antibody secretion and organization of ectopic lymphoid tissue which persisted in the absence of detectable Cp DNA. Macrophage inflammatory protein (MIP)-2/CXCL2, which recruits neutrophils and lymphocytes and is associated with ectopic lymphoid tissue formation, was secreted in the lungs post-infection. In vitro, lung epithelial cells up-regulated MIP-2/CXCL2 in response to both rough lipopolysaccharide (reLPS) and Cp infection. We conclude that Cp infection can have long-term inflammatory effects on tissue that persist after clearance of active infection.
authors.affiliation: University of Edinburgh/MRC Centre for Inflammation Research, UK. pfitch@staffmail.ed.ac.uk
authors.forename: P M
authors.initials: PM
authors.lastname: Fitch
authors.forename: N M
authors.initials: NM
authors.lastname: Wheelhouse
authors.forename: P
authors.initials: P
authors.lastname: Bowles
authors.forename: M
authors.initials: M
authors.lastname: Paterson
authors.forename: D
authors.initials: D
authors.lastname: Longbottom
authors.forename: G
authors.initials: G
authors.lastname: Entrican
authors.forename: S E M
authors.initials: SE
authors.lastname: Howie
mesh_terms: D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry / Q000166:cytology / Q000276:immunology; D002460:Cell Line; D054426:Chemokine CXCL2 / Q000235:genetics / Q000378:metabolism*; D023521:Chlamydophila Infections / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D016993:Chlamydophila pneumoniae; D002828:Choristoma / Q000276:immunology / Q000473:pathology*; D004269:DNA, Bacterial / Q000378:metabolism; D004847:Epithelial Cells / Q000187:drug effects / Q000378:metabolism; D015870:Gene Expression / Q000187:drug effects / Q000235:genetics; D007070:Immunoglobulin A / Q000276:immunology / Q000378:metabolism; D007074:Immunoglobulin G / Q000097:blood / Q000276:immunology; D007249:Inflammation / Q000473:pathology; D008070:Lipopolysaccharides / Q000276:immunology / Q000494:pharmacology; D008168:Lung / Q000378:metabolism / Q000382:microbiology / Q000473:pathology*; D008214:Lymphocytes / Q000473:pathology; D008221:Lymphoid Tissue / Q000276:immunology / Q000473:pathology*; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000473:pathology; D020545:Respiratory Mucosa / Q000378:metabolism* / Q000473:pathology; D013997:Time Factors
chemical_list: D054426:Chemokine CXCL2; C404915:Cxcl2 protein, mouse; D004269:DNA, Bacterial; D007070:Immunoglobulin A; D007074:Immunoglobulin G; D008070:Lipopolysaccharides