Objective: Unlike arteriogenesis, little is known about the effects of vasculogenesis and its major effector cells, endothelial progenitor cells (EPCs) on collateral formation. In this study, we investigated whether or not the number and function of EPCs were associated with the development of collateral formation in patients with single-vessel coronary artery disease of chronic total occlusion (CTO).
Methods and results: The subjects were patients (n=35) undergoing coronary angiography (CAG) who had CTO in one major coronary artery. EPCs were isolated from peripheral blood samples and cultured. Their phenotypes were confirmed by uptake of acetylated LDL and binding of fluorescein isothiocyanate (FITC)-labeled Ulex europaeus agglutinin 1 (UEA-1) lectin. The numbers of colony-forming units (CFUs) and the senescent cells, determined by acidic beta-galactosidase staining, were counted. The angiogenic growth factors from the culture medium were also measured by ELISA. Patients with good collaterals (n=22, Rentrop class 2 and 3) exhibited an increased number of CFUs (p=0.023), reduced number of senescent cells (p=0.010), and higher concentration of b-FGF (0.036) in the culture medium, compared with subjects with poor collaterals (n=13, Rentrop class 0 and 1).
Conclusion: Our findings suggested that EPC-mediated angiogenesis might be associated with coronary collateral formation in humans.