Chlamydophila pneumonia: Specific mRNA in aorta ascendens in patients undergoing coronary artery by-pass grafting

Abstract

The objective of this prospective study was to investigate if Chlamydophila pneumoniae (Cp)-specific DNA and mRNA are present in tissue samples from the wall of aorta ascendens in patients undergoing by-pass surgery for coronary artery disease (CAD) that includes stable angina pectoris (SAP, 25 patients) and acute coronary syndrome (ACS, 19 patients). Viable Cp was detected in 8/44 (18%) patients using reversed transcriptase PCR (RT-PCR) against bacterial mRNA with detection of cDNA using real-time PCR against the MOMP gene. Cp DNA was detected by nested PCR in 22/44 (50%) patients and by real-time PCR in 13/44 (30%) patients. In total, 24/44 (55%) patients were positive for Cp nucleic acid in any PCR. Antibodies to Cp were detected in 13/24 (54%) Cp PCR-positive and in 15/20 (75%) Cp PCR-negative patients. Nested PCR was run on throat swabs from all patients. No significant differences were noted between SAP and ACS patients regarding PCR results or serology. It has been suggested that Cp may be a 'silent passenger' picked up by the atherosclerotic plaque. Our findings of viable and metabolically active bacteria in aortic tissue add further support to the hypothesis that Cp may have an active role in the pathogenesis of atherosclerosis.

Immunoproteomic Identification and Serological Responses to Novel Chlamydia pneumoniae Antigens That Are Associated with Persistent C. pneumoniae Infections

“…After primary infection, the obligate intracellular bacteria can persist in the host (2,3). Persisting C. pneumoniae are frequently found in the respiratory tract (4 -6) or in atherosclerotic blood vessels (7)(8)(9)(10)(11) and therefore represent a potential risk factor for chronic inflammatory lung diseases (12)(13)(14) or for atherosclerosis (15). It is assumed that C. pneumoniae disseminate from the respiratory tract via infected phagocytes (16,17), which are found to contain C. pneumoniae even in healthy volunteers (18 -20).…”

Presence of Chlamydophila pneumoniae DNA but not mRNA in stenotic aortic heart valves

“…Only a few studies have succeeded in isolating C. pneumoniae from atherosclerotic tissue [9,40]. Metabolically active, replicating bacteria can also be demonstrated by the presence of bacterial mRNA as has been done in a previous study of ours in which mRNA was demonstrated in biopsies of the wall of aorta ascendens at the site of the proximal anastomosis of the vein graft in patients undergoing CAGB [19]. Detection rates of C. pneumoniae mRNA are generally lower compared with detection rates of C. pneumoniae DNA, probably partly because mRNA is more susceptible to degradation than DNA and partly because the bacteria present in calcified and disease-altered tissue may have entered a persistent and non-replicative state.…”

“…DNA and cDNA samples were subjected to real-time PCR, amplifying a fragment of the C. pneumoniae ompA gene [22] as has previously been described [19]. Control samples of a known concentration were included in each run to verify PCR reproducibility by checking for differences in Ct values.…”

“…These attributes make C. pneumoniae difficult to isolate from patient material. However, viable and metabolically active bacteria may be proven by demonstrating bacterial mRNA [19][20][21]. The aim of the present study was to investigate (1) the presence of C. pneumoniae mRNA in stenotic aortic heart valves, (2) the prevalence of C. pneumoniae DNA in PBMC and (3) the presence of C. pneumoniae DNA in stenotic aortic heart valves in patients undergoing aortic valve replacement surgery.…”

Involvement of TLR2 and TLR4, <i>Chlamydophila pneumoniae</i> and <i>Mycoplasma pneumoniae</i> in adventitial inflammation of aortic atherosclerotic aneurysm

“…In aorta, Cp antigens were found in 100% in stenotic aortic valves [24], 33% -100% in atherosclerotic aortas [25,26]. Cp DNA was detected in ascending atherosclerotic aortas in 30% and 50% of cases using real-time PCR and nested PCR, respectively [27]. However, in 148 thoracic and abdominal aortic dissections, real-time PCR (using the Taqman system) was negative for Cp in all cases [28].…”