Effects of Chlamydia Pneumoniae Infection on Inflammation and Lipid Parameters in Humans and Mice
Year: 2006
Type: article
Study design: Observational Study
Abstract: Since atherosclerosis is considered an inflammatory disease, there has been extensive research to determine whether microbial infections possibly contribute and maintain this inflammatory response.Chlamydia pneumoniae, a common causative agent of respiratory tract infections, was associated with cardiovascular diseases as early as the late 80´s.C. pneumoniae is a gram-negative bacterium which resembles viruses in terms of obligate intracellular growth.C. pneumoniae is able to infect several cell types, including circulatory monocytes, and by using monocytes as a vehicle, C. pneumoniae can disseminate from the lungs into extrapulmonary sites, including the subendothelial space of the arterial wall.In addition to inflammation, lesion development in the arterial wall requires macrophage transformation to lipidladen foam cells in the presence of an atherogenic cholesterol source like lowdensity lipoprotein (LDL) cholesterol.Chronic C. pneumoniae infection has been demonstrated to change lipoprotein distribution towards a pro-atherogenic lipid profile with increased VLDL and LDL and decreased high-density lipoprotein (HDL).Statins, a class of cholesterol drugs currently in wide use, not only decrease LDL and increase HDL cholesterol levels but also have an anti-inflammatory effect and are thus highly cardioprotective.To develop a sensitive and specific enzymeimmunoassay (EIA) method for the measurement of serum chlamydial lipopolysaccharide (cLPS) concentration, a novel approach was employed.LPS was dissociated and captured from lipoprotein and immune complexes in serum by lipopolysaccharide binding protein (LBP) in the presence of an octylglucoside detergent.The method was applied to the quantitation of cLPS in the sera of patients with acute coronary syndrome (ACS) and their controls.Significantly higher cLPS concentrations and prevalence were found in ACS patients compared to their controls.During ACS, the highest cLPS levels were found within 48 hours and the cLPS levels rapidly decreased as early as one week after the event.cLPS levels were significantly higher in acute myocardial infarction (AMI) patients as compared to patients with unstable angina (UA) at the time of hospitalization.In addition, a significant correlation was demonstrated between serum cLPS and highly sensitive C-reactive protein (hsCRP) levels throughout the one-year follow-up period in ACS patients.Our data not only strengthen the association between C. pneumoniae infection and cardiovascular disease but also highlight the role of C. pneumoniae LPS in the inflammatory process during acute coronary syndrome.
Author: Terttu Tiirola
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2117749936