Chlamydia pneumoniae and the lung

Mr, Hammerschlag

doi:10.1183/09031936.00.16510010

Cited by 94 publications

(74 citation statements)

References 55 publications

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“…Most respiratory infections caused by C. pneumoniae are mild or asymptomatic. Many studies have suggested a possible association of C. pneumoniae infection and acute exacerbations of asthma and chronic obstructive pulmonary disease (14,15,19,26,30). Seroepidemiological studies showing antibody prevalence rates in a range of 50 to 70% suggest that C. pneumoniae is widely distributed and that nearly everybody is infected with the agent at some time (15,19,24).…”

Section: Discussionmentioning

confidence: 99%

“…Seroepidemiological studies showing antibody prevalence rates in a range of 50 to 70% suggest that C. pneumoniae is widely distributed and that nearly everybody is infected with the agent at some time (15,19,24). Several surveillances of community-acquired pneumonia (CAP) have demonstrated that C. pneumoniae is the second to fourth leading pathogen of CAP, and it is believed to be responsible for 6 to 22% of CAP cases, varying with the geographical location, the age group examined and the diagnostic methods used (15,19,23). Chronic C. pneumoniae infection is currently of considerable interest because of its link to atherosclerosis (6,19,31,33,34).…”

Section: Discussionmentioning

confidence: 99%

“…Many studies have suggested a possible association of C. pneumoniae infection and acute exacerbations of asthma and chronic obstructive pulmonary disease (14,15,19,26,30). Seroepidemiological studies showing antibody prevalence rates in a range of 50 to 70% suggest that C. pneumoniae is widely distributed and that nearly everybody is infected with the agent at some time (15,19,24). Several surveillances of community-acquired pneumonia (CAP) have demonstrated that C. pneumoniae is the second to fourth leading pathogen of CAP, and it is believed to be responsible for 6 to 22% of CAP cases, varying with the geographical location, the age group examined and the diagnostic methods used (15,19,23).…”

Section: Discussionmentioning

confidence: 99%

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Comparison of Five PCR Assays for Detecting Chlamydophila pneumoniae DNA

Fukano

2004

Microbiology and Immunology

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We compared five different polymerase chain reaction (PCR) assays for the detection of Chlamydophila pneumoniae DNA using highly purified elementary bodies (EBs) and peripheral blood mononuclear cells (PBMCs) from healthy blood donors. The primers were as follows; two targeting the 16S rRNA gene, one targeting the ompA gene, one targeting the Pst‐I gene, and one targeting the 53 kDa outer membrane protein gene. The 16S rRNA touchdown enzyme time release (TETR) PCR, the ompA nested PCR and the 53 kDa nested PCR were the most sensitive assays and could detect one or more EB per assay. These three PCRs also had the same reproducibility, but the minimal amount of C. pneumoniae that could be reproducibly detected (10 of 10 testing positive) was 20 EBs. In a sample of specimens from healthy blood donors, we found 5 of 77 (6.5%) PBMCs specimens to have C. pneumoniae DNA according to the nested ompA PCR. Specimens with the 16S rRNA TETR and 53 kDa nested assays were found to have C. pneumoniae DNA 7 of 77 (9.1%) and 18 of 77 (23.4%) specimens, respectively. The other two assays failed to detect even a single positive. However, the detection rate decreased with repeated testing of the same samples. Our newly designed 53 kDa nested PCR may be as useful as the other four recommended PCR assays and may be a more useful assay for the detection of C. pneumoniae DNA from PBMCs.

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Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

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Comparison of Five PCR Assays for Detecting Chlamydophila pneumoniae DNA

Fukano

2004

Microbiology and Immunology

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“…pharyngitis, sinusitis, and otitis), central and lower airways (e.g. bronchitis, brochiolitis), as well as lung tissue (pneumonia) [6,8,10,21,38]. The phenomenon of chronicity and persistence, however, is thought to be involved in the pathogenesis of chronic inflammatory airway diseases, i.e.…”

Section: Introductionmentioning

confidence: 99%

A clinically silent respiratory infection withChlamydophilaspp. in calves is associated with airway obstruction and pulmonary inflammation

et al. 2007

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-This study was aimed at evaluating functional and inflammatory consequences of persistent chlamydial infections on the respiratory system in clinically inconspicuous calves aged 2-7 months. Thirteen calves persistently infected with Chlamydophila (C.) abortus and/or C. pecorum (Chl+) were compared to 12 calves without chlamydial infections (Chl-). In order to evaluate lung function, 36 non-invasive impulse oscillometry tests were performed per animal within 6 months. The group of chronically infected animals was distinguished by significantly higher peripheral airway resistance (indicating peripheral airway obstruction), significantly higher respiratory rates, and significantly higher minute volumes of ventilation. At the age of seven months, all calves were necropsied, broncho-alveolar lavage fluid (BALF) was obtained ex vivo, and lungs were examined histologically. Significantly higher concentrations of total protein and 8-iso-prostane (8-IP), as well as higher activities of matrix metalloprotease 2 were measured in BALF samples of Chl+ calves. Histologically, markedly activated bronchus-associated lymphoid tissue (BALT) causing partial obstruction of bronchiolar lumina was found in the apical pulmonary lobes of Chl+ calves. Chlamydial DNA was detected in the lung tissue of 7 out of 13 Chl+ calves by real-time PCR. In conclusion, respiratory chlamydial infection appeared to be associated with chronic inflammation of the lungs and airways. Despite the lack of clinical symptoms, pulmonary dysfunctions persisted in calves until the age of seven months. Data obtained in this study provide new insight illustrating the impact of nearly ubiquitous subclinical infections on the respiratory system. Chlamydia / Chlamydophila infection / airway obstruction / pulmonary inflammation / calves

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“…Whereas most respiratory infections with C. pneumoniae are self-limited (4), bacterial colonization can lead to infectious exacerbations and development of COPD (5). Because detection rate of C. pneumonia varies significantly (6), the clinical relevance of C. pneumoniae is still controversial.…”

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confidence: 99%

Perfluorocarbons Decrease Chlamydophila pneumoniae–Mediated Inflammatory Responses of Rat Type II Pneumocytes In Vitro

et al. 2006

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Chlamydophila pneumoniae alter the expression of Toll-like receptor (TLR) 4 in alveolar type II (ATII)-cells. Subsequently nuclear factor kappaB (NF-B) is activated and tumor necrosis factor-␣ (TNF-␣) and macrophage inflammatory protein 2 (MIP-2) are produced. Perfluorocarbons (PFC) are beneficial in animals with bacterial pneumonia and reduce production of TNF-␣. Using isolated ATII-cells, it was studied whether PFC prevent C. pneumoniae-induced TNF-␣ and MIP-2 release and what the underlying pathway is. PF5080 preincubation prevented C. pneumoniae-induced secretion of TNF-␣ (43 Ϯ 10 versus 661 Ϯ 41 pg/mL) and MIP-2 (573 Ϯ 41 versus 4786 Ϯ 502 pg/mL). The C. pneumoniae-induced 2.2-fold increase of TNF-␣ Receptor 1 expression was reduced by PF5080. C. pneumoniae reduced cytoplasmatic IB␣ (3.7 Ϯ 0.3 versus 14 Ϯ 1) and increased NF-B p65 (31 Ϯ 7.5 versus 3.6 Ϯ 1.1) compared with control. PF5080 prevented NF-B activation. TLR4 expression was 1.5-fold higher after C. pneumoniae incubation, but remained at control levels after PF5080 pretreatment. After 24 h of C. pneumoniae incubation, in 88 Ϯ 6% of cells bacteria were found in the perinuclear region and in 50% of these cells bacteria adhered to cellular surface. After PF5080 preincubation, C. pneumoniae were in 32 Ϯ 4% attached to and in 5 Ϯ 1% internalized in ATII-cells. Since PF5080 was found in ATII-cell membranes, PF5080 effect could be explained by an alteration of the cellular membrane, preventing activation of the inflammatory cascade. Chlamydophila pneumoniae are obligate intracellular Gram-negative bacteria that cause respiratory infections in pediatric populations and adults (1,2). Recent studies demonstrated the presence of C. pneumoniae in alveolar macrophages and ATII cells in patients with chronic obstructive pulmonary disease (COPD) (3). Whereas most respiratory infections with C. pneumoniae are self-limited (4), bacterial colonization can lead to infectious exacerbations and development of COPD (5). Because detection rate of C. pneumonia varies significantly (6), the clinical relevance of C. pneumoniae is still controversial.The effect of C. pneumoniae on isolated ATII-cells is well characterized. C. pneumoniae inhibit the surfactant metabolism of ATII-cells after internalization (7). Many of C. pneumoniae-induced effects are mediated by cytokines. C. pneumoniae act at the ATII cell membrane to induce the expression of TLR4 (8). TLR signaling is partly mediated by the transcription factor NF-B, which controls the expression of many genes involved in the inflammatory response (9). C. pneumoniae-induced activation of NF-B leads to a release of the chemokine MIP-2 and the pro-inflammatory cytokine tumor necrosis factor alpha (TNF-␣) (8) and its receptor tumor necrosis factor receptor 1 (TNFR1). Together, they play an important role in bacterial infections and modulate the inflammatory process (10).PFC-administered as liquid (11), vapor (12), or gas (13) into the lung-represent an alternative approach to treat respiratory insufficiency. Intrat...

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Chlamydia pneumoniae and the lung

Cited by 94 publications

References 55 publications

Comparison of Five PCR Assays for Detecting Chlamydophila pneumoniae DNA

Comparison of Five PCR Assays for Detecting Chlamydophila pneumoniae DNA

A clinically silent respiratory infection withChlamydophilaspp. in calves is associated with airway obstruction and pulmonary inflammation

Perfluorocarbons Decrease Chlamydophila pneumoniae–Mediated Inflammatory Responses of Rat Type II Pneumocytes In Vitro

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