Cell-mediated immune response associated with Chlamydia pneumoniae infection in atherosclerotic patients.

BACKGROUND: Chlamydia pneumoniae is an obligate intracellular bacterium that activates cell mediated immune responses; several investigations have demonstrated its strong implication in atherosclerosis. OBJECTIVES: The main objective of our study was to explore the cell-mediated immune response to C. pneumoniae infection in patients with atherosclerosis by evaluating CD14, CD8 and CD4 expression. METHODS: This investigation involved a total of 27 patients with atherosclerosis and 32 controls, among patients recruited to evaluate the association of C. pneumoniae with atherosclerosis. C. pneumoniae DNA was detected in PBMCs by nested PCR as described in our previous studies. CD4, CD8 and CD14 expression was measured by flow cytometry and data analysis was performed using FlowJo software. RESULTS: The results revealed an increase in MFI expression of CD4, CD8 and CD14 in Cpn DNA+ subjects among both patients and healthy subject controls (CD4 Cpn DNA+ = 829.11 vs. CD4 Cpn DNA- = 571.14; CD8 Cpn DNA+ = 1562 vs. CD8 Cpn DNA- = 699; CD14 Cpn DNA+ = 1513.83 vs. CD14 Cpn DNA- = 1170.70), with a statistically significant difference (p < 0.05). Furthermore, the comparison of CD4, CD8 and CD14 expression between Cpn DNA+ patients and Cpn DNA+ healthy subject controls showed a statistically significant increase in expression in the former group (p < 0.05). CONCLUSION: These data provide incentive to further explore the role of C. pneumoniae in stimulating and changing mechanisms of the cell-mediated immune response induced by C. pneumoniae antigens. This may alter immune cell-mediated responses via increased expression of CD4, CD8 and CD14 during inflammation and the development of thrombosis, leading to fatal atherosclerosis.

Chlamydia pneumoniae sero-prevalence in Moroccan patients with cardiovascular diseases.

BACKGROUND: Chlamydia pneumoniae is a pathogen associated with human respiratory tract infection, its viable presence in atherosclerotic plaques is also assumed to play significant function in cardiac diseases. Our study's main objective is to evaluate Chlamydia pneumoniae sero-prevalence in Moroccan patients with cardiovascular diseases using and comparing two serological methods. METHODS: Two hundred eighteen patients were enrolled; serums were tested by microimmunofluorescence to explore the sero-prevalence. Simultaneously 74 serums were analyzed by both immunoblot and micro-immunofluorescence to evaluate recombinant proteins diagnosis value. RESULTS: MIF results revealed 81% male and 84.5% female positive cases. The comparative study among 74 patients showed 78% men and 89% women positive cases by immunoblot, whereas MIF showed respectively 80% and 72%, a significant concordance between these methods was revealed. However, this comparison showed also two types of discrepancies, which may be related to difficulties in antigens detection by micro-immunofluorescence resulting from their structure complexity, or the antibodies reactivity with species' common antigens. CONCLUSIONS: The study revealed a high sero-prevalence of Chlamydia pneumoniae in the studied population, a big interest of recombinant protein was also revealed in the diagnosis accuracy. We suggest therefore using immunoblot for diagnosis confirmation because it provides additional useful information.