Factors influencing spontaneous mobilization of CD34+ and CD133+ progenitor cells after myocardial infarction

Abstract

Bone marrow-derived circulating progenitor cells (BM-CPCs) are mobilized into adult peripheral blood (PB) during acute myocardial infarction (AMI) and may contribute to the regeneration of infarcted myocardium. The purpose of the present study is to determine whether mobilization of BM-CPCs into PB depends on cardiovascular risk factors (CVRFs), age of patients, infarct associated inflammatory markers, and left ventricular function after AMI. Peripheral blood concentrations of CD34/45(+) and CD133/45(+) BM-CPCs were measured by flow cytometry in 44 patients after AMI and in 16 subjects with atypical chest pain acting as controls. Mobilization of CD34/45(+) and CD133/45(+) BM-CPCs on day 1 after AMI showed significant negative correlation with age, the number of CVRFs, infarct size, creatine phosphokinase peak in bivariate as well as in multivariate analyses. We additionally found a positive correlation of CD34/45(+) and CD133/45(+) BM-CPCs mobilization on day 1 after AMI with global ejection fraction (EF) in bivariate analysis but could not confirm this in multivariate analysis. Elevated of C-reactive protein (CRP) and leukocyte levels on day 1 after AMI were significantly associated with decreased concentrations of CD34/45(+) BM-CPCs. The concentrations of CD34/45(+) and CD133/45(+) BM-CPCs significantly increased in AMI patients, with the peak on day 7 as compared to the control group. The mobilization of CD34/45(+) and CD133/45(+) BM-CPCs into the PB depends on many factors, i.e. the number of CVRFs, age, infarct size and inflammatory markers of patients. Most importantly, the severity of the circulatory dysfunction and the amount of necrotic myocardial tissue are the main determinants. Moreover, this spontaneous mobilization of BM-CPCs may serve as a very important surrogate for infarct size as well as for global EF and it may determine the regenerative potency after AMI.