A paper in Nature, summarised in The Scientist, reports success in making progenitor cells, that naturally exist in the outer layer of heart tissue, proliferate, migrate into heart muscle and transform into heart muscle cells (cardiomyocytes). The research in mice “suggests that the human heart could be encouraged to repair itself after a heart attack by stimulating a pool of resident adult progenitor cells.”
While it is a way to go before such manipulations could be used for curing heart damage and disease in people, it is an interesting alternative to stem cells for achieving organ repair inside the body.