Objective Myeloperoxidase (MPO) and CD11b/CD18, markers of leukocyte activation, are involved in the pathogenesis of atherosclerosis. The aim of the study was to investigate the plasma MPO level and CD11b/CD18 expressions on leukocytes in patients with coronary heart disease (CHD).

Methods This case-control study included 157 patients with angiographically proven CHD (cases). Controls included 78 subjects with normal coronary angiograms. MPO was measured using an enzyme immunoassay. The method of immunofluorescence flow cytometry was performed for measuring CD11b/CD18 expression on leukocytes in all subjects. High sensitivity- Creactive protein (hs-CRP), WBC and PMN were also measured and analysed.

Results Plasma level of MPO in CHD group was much higher than that in controls [(332.05±167.56) pg/ml vs (277.81±142.68) pg/ml, p<0.05]. CD11b/CD18 level differed significantly between CHD group and control group [(53.7±24.1) vs (23.0±10.2), p<0.01]. The levels of hs-CRP and WBC were markedly increased in cases than those in controls (p<0.05–0.01). MPO levels correlated positively with CD11b/CD18 and WBC levels (r=0.539, p<0.01and r=0.3, p<0.05, respectively), but had no significant correlation with CRP, TC, TG, LDL, HDL, IMA, cTnI.

Conclusion In conclusion, the levels of MPO, CD11b/CD18, hs-CRP and WBC are elevated in patients with CHD. Inflammation may be one of important reasons for ACS occurrence and MPO, leukocytes and their CD11b/CD18 expressions and hs-CRP were involved in the occurrence of ACS together. MPO may be an inflammation marker independent of hs-CRP.