"In order for the use of EPC to become practical in human patients, we need an assay that is quick, reliable and accurate," said Povsic. "Since there are so few EPCs circulating, we literally need a method that can find a needle in a haystack. Our tests so far measuring using ALDH activity to measure EPCs represents a novel approach to solving this problem.
"The paradigm of atherosclerosis is changing. In the past we only thought of the risk factors we could measure, such as cholesterol, lipids and some new markers like c-reactive protein," Povsic continued. "We're learning that atherosclerosis is a balancing act between damage and repair, and now we may have a test that gives us insight into the repair portion of the equation."
"If the results of this study are borne out, measuring EPCs could be a better test for defining an individual patient's risk for heart disease," Povsic said. "Theoretically, patients who are found to have low levels of EPCs would be those patients we may want to treat more aggressively."
ALDH is produced in high amounts by stem cells in the bone marrow as part of the process of maintaining the longer lifespans of these cells. Researchers have used ALDH assays to measure the number of stem cells in the bone marrow, so the team has extended this assay to detect levels of EPCs, which are progenitor cells in the blood which may repair one's arteries.
Current methods for measuring EPCs are conducted in the laboratory and are laborious and time-consuming, Povsic said. Researchers first remove all the immune system cells from a blood sample, then culture the remaining cells and then count
Source:Duke University Medical Center