In their study, featured in the February 1 issue of the Journal of Clinical Investigation the authors isolated these human cells at the single cell level and were able to differentiate them into all different cell types. When single human bone marrow–derived stem cells were allowed to divide to form a large population, they were transplanted into a rat model of myocardial infarction. This improved cardiac function because the cells stimulated release of growth factors and anti-apoptotic agents that, in turn, increased the proliferative potential of cardiomyocytes and enhanced survival of host myocardium. This is the first report of endogenous cardiomyogenesis after adult human stem cell transplantation.
Myocardial infarction and heart failure are associated with major morbidity and mortality and there are currently limited therapeutic opportunities for intervention. This study provides the first demonstration of a single, human stem cell population derived from the bone marrow that has the capacity to induce generation of new heart cells and formation of new blood vessels ?two key components of successful myocardial repair. The results provide a foundation on which new approaches to repair the damaged heart can be based.