The association of endothelial progenitor cells and monocytes with atherosclerosis and coronary collateral growth

Endothelial progenitor cells (EPC) have a regenerative role in the vascular system. In this study, we aimed to evaluate the effects of EPC and inflammatory cells on the presence and extend of coronary artery disease (CAD), and the coronary collateral growth in patients who are suspected of having CAD. We enrolled 119 eligible patients who underwent coronary angiography consecutively (mean age: 59,2 ± 9,3 years). The association of circulating inflammatory cells and EPC (defined by CD34+KDR+) with the presence, severity and extend of CAD and the collateral growth were investigated. Thirty of 119 patients had normal coronary artery (NCA, %25, 55 ± 9 years), 82 had CAD (%69, 61 ± 8 years) and 7 had nonischemic cardiomyopathy (%8, 63 ± 12 years). Among the patients with CAD, the percent degree of luminal stenosis was <50% in 12 patients; 50-90% in 35 patients; and ?90% in the other 35 patients. Circulating inflammatory cells were higher (leukocytes, 7150 ± 1599 vs 8163 ± 1588 mm?3, p=0.001; neutrophils, 4239 ± 1280 vs 4827 ± 1273 mm?3, p=0.021; monocytes, 512 ± 111 vs 636 ± 192 mm?3, p=0.001) and EPCs were lower in CAD group than NCA group (0.27±0.15% vs 0.17±0.14%, p<0.001 ve 21±15 vs 13±12 mm?3, p=0.004). When we investigated the collateral growth, we found that patients with good collateral growth had significantly higher EPC in comparison to patients with poor collateral growth (0.10±0.05% vs 0.22±0.17%, p=0.009; 7±3 vs 18±15 mm?3, p=0.003). Endothelial progenitor cells can be mobilised from bone marrow to induce the coronary collateral growth in case of myocardial ischemia even in presence of the vascular risk factors and extensive atherosclerosis. This finding may be supportive to investigate the molecules which can specifically mobilise EPC without inflammatory cells.