Direct conversion in the heart: a simple twist of fate.

Nature advance online publication April 18 2012; doi:; DOI: 10.1038/nature11044 In a recent issue of Nature, Qian et al (2012) show that by injecting adult mouse hearts with a few transcription factors on a retroviral vector, they can switch cardiac fibroblasts—the workhorse supporting cells of the heart—into cardiomyocytes, the beating muscle cells driving the contractile forces that pump blood. When injected into the hearts of mice with induced myocardial infarctions, the treatment reduced the size of the infarct and improved cardiac function to a modest but significant degree. Until now, cell replacement therapies have dominated the research landscape of cardiac regenerative medicine. This study hints that a gene therapy approach for reprogramming may provide an alternative for generating new cardiomyocytes within failing hearts.