A colony of human embryonic stem cellsWIKIMEDIA COMMONS, RYDDRAGYNEmbryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), reprogrammed from adult differentiated cells, reportedly behaved differently from one another in myriad studies. But these functional differences between cell types may not be as drastic as previously thought, according to a team led by Konrad Hochedlinger of Harvard University, which published its findings Monday (October 26) in Nature Biotechnology.
Genetic individuality could explain some differences between human iPSCs and ESCs, the authors proposed. There may be discrepancies when comparing iPSCs from one donor to ESCs from another simply because the individuals have different genetic makeups to start—including whether the cells originated from males or females.
To obtain genetically identical stem cells, the researchers sampled two ESC lines, allowed the cells to differentiate, and then reprogrammed them into iPSCs. This method gave them iPSCs that contained the same genes as the ESCs for experimentation. As expected, the iPSCs were more similar to their embryonic parents than to each other. However, the iPSCs still differed from the ESCs in gene expression; 49 genes had consistently different activity between the two types of cells.
Despite the expression ...