Donor stem cells as safe as patient's own for heart repair
Results of stem-cell research using marrow donated by others, without the need for blood or tissue typing, raises hopes for a new therapy
Researchers are reporting that stem cells donated by strangers proved as safe and effective as patients' own cells for helping restore heart tissue, a key advance in repairing hearts damaged by heart attacks.
The work involved just 30 patients in Miami and Balitmore, but proves the concept that anyone's cells can be used to treat such cases. Doctors are excited because this suggests that stem cells could be banked for off-the-shelf use after heart attacks, just as blood is kept on hand now.
Results were discussed on Monday at an American Heart Association conference in California and published in the .
The study used a specific type of stem cells from bone marrow that researchers believed would not be rejected by recipients. Unlike other cells, these lack a key feature on their surface that makes the immune system see them as foreign tissue and attacks them, explained the study's leader, Dr Joshua Hare of the University of Miami.
The patients in the study had suffered heart attacks years earlier, some as long as 30 years ago. All had developed heart failure because the scar tissue from the heart attack had weakened their hearts so much that they grew large and flabby, unable to pump blood effectively.
Researchers advertised for people to supply marrow. The cells were removed from the marrow using a needle into the hip and then amplified for about a month in a lab at Baltimore's Johns Hopkins University, then returned to Miami to be used for treatment, which did not involve surgery. The cells were delivered through a tube pushed through a groin artery into the heart near the scarred area. Fifteen patients were given cells from their own marrow and 15 others, cells from strangers.
About a year later, scar tissue had been reduced by about one-third. Both groups had improvements in how far they could walk and in quality of life. There was no significant difference in one measure of how well their hearts were able to pump blood, but doctors hope these patients will continue to improve over time, or that refinements in treatment will lead to better results. The big attraction is being able to use cells supplied by others, with no blood or tissue matching needed.
