In vitro reprogramming of fibroblasts into a pluripotent ES-cell-like state

Four transcription factors Oct4, Sox2, c-Myc and Klf4 are known to convert fibroblasts to pluripotent stem cells, if Fbx15 expression is also selected. But the induced stem cells were shown to be distinct from normal embryonic stem cells. However, if cells expressing Nanog and Oct4 are selected, then the reprogrammed fibroblasts are similar to embryonic stem cells in both biological potency and epigenetic state.