Human nuclear transfer embryonic stem cells expressing OCT-4 marker of early embryosCOURTESY OF OHSU CENTER FOR EMBRYONIC CELL AND GENE THERAPYIn the process of converting a somatic cell to a stem cell, researchers have questioned whether the resulting cells retain characteristics of their prior, non-stem-cell states. Applying two pioneering approaches to create human pluripotent stem cells from somatic cells—by inducing pluripotent stem cells (iPSCs) or using a process called somatic cell nuclear transfer (SCNT)—researchers from Oregon Health & Science University (OHSU) and their colleagues have compared the genomic and epigenomic landscapes of the resulting cell types. They found that the genomes of stem cells created through SCNT more closely match those of embryonic stem cells (ESCs) derived from early human embryos. The team’s comparative analysis was published today (July 2) in Nature.
Shoukhrat Mitalipov, a reproductive biologist and director of the Center for Embryonic Cell and Gene Therapy at OHSU, led the team that developed the SCNT approach just last year. For the present study, Mitalipov said he and his coauthors wanted to better understand the degree to which this new class of pluripotent cells were comparable to iPSCs.
Both iPSCs and SCNT-derived cells showed similar numbers of acquired genomic deletions and duplications. But while the iPSCs retained some of the epigenetic and gene expression patterns of their parental somatic counterparts, the SCNT-derived cells had transcriptional and epigenetic patterns that were more like in vitro fertilized (IVF) ESCs, which are considered the most authentic form of ESCs, as they are directly isolated from human embryos.
Unlike IVF ...
