Patient-own cells help restore pumping of the heart

Using stem cells to regenerate functionality of damaged organs is something that has caught the attention of many researchers. Especially the patient's own stem cells have gained interest over the years: when harvested, these could be more easily transplanted back because the immune system does not recognize them as foreign. In a clinical trial, scientists have shown that using adult stem cells in patients that have suffered from a heart attack, can revive the heart's pumping function. Over time, the scientists noted that the damaged pump was slowly being restored after being treated with stem cells that were derived from the patient's own inventory.

Study
In the study, conducted by the University of Louisville, several of the patients treated with stem cells found their ejection fraction increased from 30 percent to 38 percent four months after treatment started. The ejection fraction represents the percentage of blood that is forced out of the heart by each pump cycle. In healthy people, this percentage lies between 50 and 65 percent. A year after being injected with stem cells, the ejection fraction was up to 42 percent, slowly reaching normal values. In addition, the size of the infarct area, damaged by the heart attack and converted to useless scar tissue, decreased by about one-third after a year.

Future
The present study was a small scale study which primarily focused on safety and efficacy. Because of the promising results, the researchers claim they want to test the treatment in a larger group of patients, and follow them for longer periods of time. In addition, the reported study is still going on, with more long-term results on the way. It is interesting to know whether the process of heart regeneration keeps up over time, to let the heart reach normal ejection fraction again.

Growing tissues
Though stem cells have long promised this type of treatment, it is actually one of the few clinical studies that have actually shown a benefit on a functional level. We have been able to culture stem cells in the lab and give them the properties we want, but using them as a therapy proved to be much harder.  In the reported study, scientists used so-called adult stem cells. These have already committed to a specific cell line, and can no longer be turned into any type of cell, a feature attributed often to the controversial embryonic stem cells. For their study, the scientists harvested cardiac stem cells from their patients, which were subsequently cultured in the lab. After generating enough cells, about one million per treatment, they were transplanted back into the patient, after which they contributed to heart function.