July 26, 2005
Stem-Cell Study May Point to Cure for Heart AttacksTopics: Medicine
The stem cells used in this study were not embryonic stem cells, they were mesenchymal stem cells derived from bone marrow. Because they remain in an early stage of development, mesenchymal stem cells do not trigger an immune response, unlike what would happen if more developed stem cells were used.
Stem cell therapy can be used effectively to treat heart attacks in pigs, according to a study published in the Proceedings of the National Academy of Sciences. Stem cells harvested from a healthy pig's bone marrow and injected into another pig's damaged heart restored its function and repaired damaged heart muscle by 50 to 75 percent within just two months.
Two participants already have been enrolled in a Phase I clinical trial, which is designed to test the safety of injecting adult stem cells at varying doses in patients who recently have suffered a heart attack. In total, 48 patients will participate in this study, which is taking place at several sites across the country. Results are expected by mid-2006.
"Ultimately, the goal is to develop a widely applicable treatment to repair and reverse the damage done to heart muscle that has been infarcted, or destroyed, after losing its blood supply," says cardiologist Joshua Hare, MD, professor of medicine at The Johns Hopkins University School of Medicine and its Heart Institute, and senior author of the study and lead trial investigator.
"There is reason for optimism about these findings, possibly leading to a first-ever cure for heart attack in humans," says Dr. Hare.
"If a treatment can be found for the damage done by a heart attack to heart muscle, then there is the potential to forestall the serious complications that traditionally result from a heart attack, including disturbances of heart rhythm that can lead to sudden cardiac death, and decreased muscle pumping function that can lead to congestive heart failure," he notes.
The researchers are using a special kind of stem cell in an early stage of development, called adult mesenchymal stem cells, to avoid potential problems due to the tendency of the human immune system to attack stem cells from sources other than the self. "Using mesenchymal stem cells also avoids potential problems with immunosuppression, in which every human's immune system might attack stem cells from sources other than itself."
Bone marrow adult stem cells do not have the same potential to develop into different organ tissues, as do embryonic stem cells, whose use is more controversial.
Some related previous Hyscience posts on stem cells:
Cord blood may become source of stem cells
Posted by Hyscience at July 26, 2005 6:27 PM
While this study may be important for Americans because the Phase I clinical trial is the first stage at getting regulatory approval in the U.S. However, in the greater sphere of science and actual treatment it lags behind developments in other parts of the world.
Similar trials have already begun (and some completed) in countries such as Brazil, germany, and Thailand.
In Thailand, two Bangkok hospitals are already treating patients using their own adult stem cells. Both American and Thai patients have undergone stem cell therapy in Bangkok. Those with heart disease that could be helped by stem cell therapy do not have to wait 5 to 10 years. Therapy is available now.
Posted by: Paul at July 28, 2005 3:25 AM
Articles Related to Medicine:
- Stem-Cell Study May Point to Cure for Heart Attacks - Jul 26, 2005