Monomeric C-reactive protein in coronary artery disease

Aim. To develop a method for measuring circulating monomeric C-reactive protein and to determine the levels of C-reactive protein isoforms (native pentameric C-reactive protein and monomeric C-reactive protein) in patients with stable coronary artery diseases and acute myocardial infarction.

Methods. Plasma and blood serum samples were collected from 22 patients with stable coronary artery disease (CAD), 14 patients with acute myocardial infarction at days 2-3, and 11 healthy volunteers. The analysis was performed using flow cytofluorometry FACS Cantoll and a set of functional particles Cytometric Bead Array (BD Biosciences, USA). Antibodies for CRP (clones 328 and 372 from ImTek, Russia, and clone 8C8 from Sigma-Aldrich, USA), гСКР-GAH (with antibodies for CRP), native CRP (ImTek, Russia) and recombinant monomeric CRP (received as a gift from Dr. L. Potempa) were used in the analysis.

Results. A novel laboratory kit for measuring blood levels of monomeric CRP has been developed. Patients with CAD demonstrated elevated plasma levels of CRP, whereas healthy subjects reported the levels below the lower cut-off. Patients with stable CAD had mCRP concentration of 2.34 (1.42; 3.27) pg/L, whereas patients with acute MI had the highest level of 16.76 (3.65;54.83) pg/L (p = 0.0002, Kruskal-Wallis One Way Annova). There were no any correlations between mCRP levels and nCRP, hs-CRP and IL-6.

Conclusion. The novel laboratory kit allows measuring monomeric C-reactive protein and provides novel data on the role of mCRP in the development and progress of CAD. Obtained data suggest that monomeric C-reactive protein can play no less important role than native C-reactive protein in the diagnosis and progress of cardiovascular diseases as well as other diseases associated with the inflammatory process.

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