Investigating the extremes of the continuum of paracrine functions in CD34-/CD31+ CACs across diverse populations.

Unlabelled: Paracrine function of circulating angiogenic cells (CACs) is thought to contribute to vascular maintenance. We previously identified S100A8 and S100A9 secreted from physically inactive individuals' CD34/CD31 CACs as negative regulators of capillary-like network formation. The purpose of this study was to investigate further the extremes of the continuum of CAC paracrine actions using two distinctly different groups representing "healthy" and "impaired" CAC function.