RESEARCH New study undercuts promise of adult stem cells

A researcher found the results to be a 'complete surprise.'
CHICAGO TRIBUNE
CHICAGO -- Researchers reported last week that bone marrow stem cells were unable to regenerate damaged heart tissue in laboratory animals, suggesting that a proposed revolutionary therapy for the 1.1 million Americans who suffer heart attacks each year may be destined to fail.
The study is the latest to cast doubts on the scientific dream that a patient's own mature stem cells -- instead of stem cells from embryos -- could someday be used to replace cells damaged or missing because of genetic diseases, tissue injuries or degenerative illnesses.
"This was a complete surprise and a considerable disappointment," said University of Chicago researcher and cardiologist Dr. Elizabeth McNally, who directed the study with colleagues from the University of Chicago and the University of California, San Francisco.
Published
The study was published in the Journal of Clinical Investigation.
Scientists previously had demonstrated that these cells, which normally make blood, could home in on areas of damaged muscle and suggested they matured into working heart or muscle cells.
Animal experiments were so encouraging that human clinical trials are under way with heart attack and congestive heart failure victims.
Working with mice, the McNally team found that the bone marrow stem cells did manage to find their way to areas of damaged heart muscle, infiltrate into these regions and proliferate. But they failed to take the crucial final steps and produce a muscle protein called sarcoglycan, which is essential for normal heart and skeletal muscle function.