Circulating CD34+ cells, metabolic syndrome, and cardiovascular risk.

AIMS: Circulating progenitor cells are believed to participate in cardiovascular (CV) homeostasis and their exhaustion has been linked to CV damage. As general agreement on their characterization is lacking, this work was carried out to assess the relationships between different antigenic profiles of progenitor cells and CV risk, with special regard to metabolic syndrome (MetSyn). METHODS AND RESULTS: CD34, CD133, and KDR were used to quantify circulating progenitors in 214 subjects at different levels of CV risk. In a cross-analysis of six different cell subtypes (CD34(+), CD133(+), CD34(+)CD133(+), CD34(+)KDR(+), CD133(+)KDR(+), and CD34(+)CD133(+)KDR(+)), CD34(+) progenitors showed the best correlation with CV parameters and risk estimates. Components of the MetSyn were all characterized by reduction of CD34(+) cells and acted synergistically in decreasing CD34(+) cell count. Moreover, CD34(+) cell count demonstrated a high performance in detecting high CV risk. CONCLUSION: These data demonstrate that CD34 identifies progenitor cells linked to CV risk, showing a close negative correlation between CD34(+) cells and CV risk, as well as a synergic detrimental effect of clustered metabolic components. Progenitor cell count may be used as a surrogate marker of CV risk, whereas extensive antigenic characterization may not be useful for this purpose.