Generation of integration-free induced hepatocytes from mouse fibroblasts

Previous studies demonstrated that hepatocyte-specific transcription factors could directly convert fibroblasts into functional hepatocytes-like cells, namely induced hepatocytes (iHeps) using viral systems. However, viral integration into host genome causes insertional mutation and risk of tumorigenecity. we showed iHeps could be generated from MEFs using the integration-free system. They were expandable in vitro and showed hepatic features, similar to primary hepatocytes. iHeps_G4H1F3 transfected (Episomal vectors) and iHeps_G4H1F3 transduced (pMXs) were duplicate, respectively. MEFs and primary hepatocytes were used as negative and positive controls, respectively.