Genetically Engineered Fluorescent Induced Pluripotent Stem Cells (iPSC)

iPS cells were reprogrammed from the fibroblasts of a healthy patient, using the four Yamanaka factors. The cells were genetically engineered to express EGFP by TALEN-mediated targeting to the AAVS1 locus. The image captures the constitutive GFP expression of the cells, as well as immunostaining for surface (Tra-1-60) and nuclear (Nanog) pluripotency markers. iPSCs are adult cells that have been genetically reprogrammed to an embryonic stem cell–like state by being forced to express genes and factors important for maintaining the defining properties of embryonic stem cells.