EPC mobilization after erythropoietin treatment in acute ST-elevation myocardial infarction: the REVEAL EPC substudy.

Erythropoietin (EPO) was hypothesized to mitigate reperfusion injury, in part via mobilization of endothelial progenitor cells (EPCs). The REVEAL trial found no reduction in infarct size with a single dose of EPO (60,000 U) in patients with ST-segment elevation myocardial infarction. In a substudy, we aimed to determine the feasibility of cryopreserving and centrally analyzing EPC levels to assess the relationship between EPC numbers, EPO administration, and infarct size.

Calorie restriction and dwarf mice in gerontological research.

What aging process is delayed by calorie restriction (CR) and mutations that produce long-lived dwarf mice? From 1935 until 1996, CR was the only option for increasing the maximum lifespan of laboratory rodents. In 1996, the mutation producing the Ames dwarf mouse (Prop-1(-/-)) was reported to increase lifespan. Since 1996, other gene mutations that cause dwarfism or lower body weight have been reported to increase the lifespan of mice.

Common endothelial progenitor cell assays identify discrete endothelial progenitor cell populations.

Background: Multiple measures of endothelial progenitor cells (EPCs) have been described, but there has been limited study of the comparability of these assays. We sought to determine the reproducibility of and correlation between alternative EPC assay methodologies.

Methods: We simultaneously assessed EPC numbers in 140 patients undergoing cardiac catheterization using the 2 most commonly used culture techniques: endothelial cell outgrowth and colony-forming unit (CFU).

Aldehyde dehydrogenase activity allows reliable EPC enumeration in stored peripheral blood samples.

Background: Interest in the biology of endogenous progenitor cells (EPCs) continues to grow as evidence of their role in vascular repair mounts. EPC enumeration requires specialized laboratory techniques and is performed immediately after sample acquisition, limiting the clinical contexts in which EPC enumeration can be performed and the ability to increase sample sizes through multi-center participation.

Methods: We compared the numbers of EPCs enumerated in samples processed immediately after acquisition (n = 36) with EPCs enumerated in specimens stored for 24 hours or after cryopreservation of mononuclear cells (MNC) using two EPC identification strategies: cell surface marker expression (CD133/CD34) and aldehyde dehydrogenase activity (ALDH(br) cells).

Circulating progenitor cells can be reliably identified on the basis of aldehyde dehydrogenase activity.

Objectives: Our objective was to develop and assess a novel endogenous progenitor cell (EPC) assay based on aldehyde dehydrogenase (ALDH) activity, and to define the relationship of ALDH-bright (ALDH(br)) cells with previously defined EPCs, patient age, and extent of coronary artery disease.

Background: Accurate assessment of circulating EPCs is of significant interest, yet current assays have limitations. Progenitor cells display high levels of ALDH activity.