Bone-marrow stem cells as a source for cell therapy.

Bone marrow stroma contains a subgroup of cells which can be guided in vitro to differentiate, and express cardiomyocyte phenotype. In vivo, these cells can become cardiomyocytes when implanted into the myocardium, in response to signals from the microenvironment. They appear to participate in the physiologic healing process of tissue injury, such as myocardial infarction, by being recruited from the bone marrow, traffic via the circulation and home in to the injured site. Thus such cells may be employed to therapeutically augment the myocardial repair for patients who suffer cardiac damages, which may lead to heart failure. Optimization of the cell implant strategy, and further exploration of the preliminary findings that such adult stem cells may be uniquely immuno-tolerant and thus may be used as "universal donors", will further enhance the clinical significance of adult stem cell-based regenerative therapy for heart failure.