Cardiac regeneration using HLA-matched induced pluripotent stem cells—no monkey business, but still a long and winding road ahead

The discovery that somatic cells such as skin fibroblasts can be reprogrammed to induced pluripotent stem cells (iPSCs), which are capable of differentiating to any somatic cell type (1-3), has sparked considerable interest in the field of cardiology. Human iPSC-derived cardiomyocytes are now widely used to investigate pathomechanisms of cardiac diseases and to evaluate cardiac actions of drugs (4,5). However, the other great promise of iPSC technology in cardiology is that these cells, which unquestionably have the potential of differentiating to cardiomyocytes, may be used to replace myocardium lost due to infarction or regenerate failing hearts in non-ischemic cardiomyopathies.