Heartfelt conversion

A group of Chinese and American researchers have developed the first virus-free cellular reprogramming method that can turn skin cells into cardiac progenitors at an efficiency high enough for clinical use. The U.S. arm is spinning out Qurgen Inc., and plan to use the system for replacing tissue damaged by myocardial infarction (MI) or other heart diseases. Most methods for converting fibroblasts into cardiac muscle cells involve an interim step of induced pluripotent stem (iPS) cells, but that carries risks of tumors if the transplanted cardiomyocytes are contaminated with any unconverted stem cells.

As a result, groups in academia and industry have looked for systems that directly reprogram the fibroblasts into cardiomyocytes, often using viruses to express transcription factors that drive the transformation. But those viruses present safety risks too...