title: The acute phase reactant response to respiratory infection with Chlamydia pneumoniae: implications for the pathogenesis of atherosclerosis.
abstract: The acute phase response to Chlamydia pneumoniae infection was analyzed over a 72 h period post-infection in C57BL/6J mice. A single intra-nasal inoculation stimulated statistically significant increases in the plasma levels of IL-2, IL-5, IL-6, IL-10, IL-12, GM-CSF, IFN-gamma, and serum amyloid A but not TNF-alpha, IL-1beta, IL-4 and serum amyloid P. There was also a decrease in the activity of the HDL protective enzyme paraoxonase as well as a reduced ability of HDL to prevent oxidation of palmitoyl-2-arachidonyl-sn-glycerol-3-phosphocholine by hydroperoxyoctadecadienoic acid at 48 and 72 h post-infection. To determine whether the C. pneumoniae induced acute phase response had any effect on atherosclerotic plaque stability, we measured the frequency of intra-plaque hemorrhage as a marker of plaque disruption in the innominate arteries of apolipoprotein E deficient mice at 29-30 weeks and 1.5-2.0 years of age. There was an increased frequency of intra-plaque hemorrhage only in the older mice infected with the live organism (8/14) as compared to mice treated with killed C. pneumoniae (2/11) or sham inoculated with PBS (2/12). These results suggest that acute phase reactant proteins produced in response to pulmonary infection with C. pneumoniae may contribute to the progression and destabilization of atherosclerotic lesions.
authors.affiliation: Department of Epidemiology, School of Public Health, University of Washington, Seattle, WA 98195, USA.
authors.forename: Lee Ann
authors.initials: LA
authors.lastname: Campbell
authors.forename: Kambiz
authors.initials: K
authors.lastname: Yaraei
authors.forename: Brian
authors.initials: B
authors.lastname: Van Lenten
authors.forename: Alan
authors.initials: A
authors.lastname: Chait
authors.forename: Erwin
authors.initials: E
authors.lastname: Blessing
authors.forename: Cho-Chou
authors.initials: CC
authors.lastname: Kuo
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Nosaka
authors.forename: Jerry
authors.initials: J
authors.lastname: Ricks
authors.forename: Michael E
authors.initials: ME
authors.lastname: Rosenfeld
mesh_terms: D000209:Acute-Phase Proteins / Q000378:metabolism*; D000818:Animals; D050197:Atherosclerosis / Q000473:pathology*; D023521:Chlamydophila Infections / Q000150:complications* / Q000276:immunology; D016993:Chlamydophila pneumoniae / Q000276:immunology* / Q000472:pathogenicity*; D006470:Hemorrhage / Q000139:chemically induced / Q000473:pathology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018410:Pneumonia, Bacterial / Q000150:complications* / Q000276:immunology
chemical_list: D000209:Acute-Phase Proteins