Abstract
Despite significant progress in pharmaceuticals and medical technology, heart failure remains a major worldwide problem. Most often, heart failure manifests when myocardium becomes injured, dies, and is replaced by fibrous scar tissue. Until recently, it was thought that the heart had no ability to regenerate injured cardiomyocytes, but in 2001, Orlic et al. (1,2) fundamentally altered our thinking by showing that mobilized or directly applied bone marrow (BM)–derived progenitor cells improved myocardial function after infarction. With this observation, the race was on to find the methods and cells that would provide the greatest benefit for cardiac regeneration (3).