Published November 17, 2011
University at Buffalo researchers have generated heart cells using a stem cell therapy that may apply to people with ischemic heart disease.
The scientists spurred the growth of healthy heart cells in animals with ischemic heart disease by infusing them with stem cells derived from cardiac biopsies, or “cardiospheres.”
The number of heart muscle cells increased 30 percent within a month after the animals received the cardiosphere-derived cells (CDCs).
This finding—presented at the American Heart Association’s annual meeting—overturns conventional wisdom that heart cells are terminally differentiated and thus unable to divide.
The research is in a preclinical phase, but UB scientists expect that studies examining the effectiveness of this approach in patients could take place within two to three years or sooner.
Ischemic heart disease from coronary artery narrowing and prior heart attacks is the most common cause of heart failure.
While other investigators have largely concentrated on regenerating muscle in scarred tissue, the UB group has shown that cardiac repair can be brought about by infusing the CDCs slowly into coronary arteries, which deliver them throughout the heart.
“Whereas most research has focused upon irreversible damage and scarring following a heart attack, we have shown that a single CDC infusion is capable of improving function in areas of the heart that are viable but not functioning normally,” explains study co-investigator John M. Canty Jr., MD, the Albert and Elizabeth Rekate Professor of Medicine, and UB’s chief of cardiovascular medicine.
Areas of myocardial dysfunction without fibrotic scarring are common in patients with heart failure from coronary artery disease, Canty adds. They arise from remodeling in response to a heart attack as well as adaptations that develop from periods of inadequate blood flow, sometimes called “hibernating myocardium.”
Gen Suzuki, MD, research assistant professor of medicine and co-investigator on the study, says the findings show “that cells derived from heart biopsies can be expanded outside of the body and slowly infused back into the coronary arteries of animals with chronic dysfunction from restricted blood flow.
“The new cardiac muscle cells are small and function more normally than diseased large, hypertrophied myocytes.”
Infusing the stem cell formulations directly into coronary arteries not only allows them to be spread throughout the heart, but it is also much simpler than injecting cells directly into heart muscle, which requires equipment not widely available.
The research was funded by the Department of Veterans Affairs; the Empire State Stem Cell Board; the National Heart, Lung and Blood Institute of the National Institutes of Health; and the Albert and Elizabeth Rekate Fund.
Other co-investigators on the study were Thomas Cimato, MD, PhD, assistant professor of medicine, and Merced Leiker, research associate in the Division of Cardiovascular Medicine.