Figure 1

Overview of approach used to generate iPS cells by transient transfection of plasmid DNA. A) Schematic and timeline of the protocol used to generate human iPS cells by sequential transient transfection of plasmids expressing OCT4, NANOG, SOX2, and LIN28 cDNAs. B) Photographs showing colonies expressing alkaline phosphatase activity after lentivirus-based reprogramming (left) or plasmid transfection-based reprogramming (right) of human fibroblasts.