Breakthrough findings by Haruko Obokata and colleagues at the RIKEN Center for Developmental Biology (CDB) look to upset the canonical views on the fundamental definitions of cellular differentiation and pluripotency. In a pair of reports in Nature, Obokata shows that ordinary somatic cells from newborn mice can be stripped of their differentiation memory, reverting to a state of pluripotency in many ways resembling that seen in embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs).
The conversion process, which Obokata has named STAP (stimulus-triggered acquisition of pluripotency), requires only that the cells be shocked with a dose of sublethal stress, such as low pH or mechanical force, in order to trigger a remarkable transformation, in which the cells shrink, lose the functional characteristics specific to their somatic cell type, and enter a state of stem cell-like pluripotency. Such STAP cells show all the hallmarks of pluripotency, and contribute to chimeric mice and germline transmission when injected into early stage embryos.
This work was done in collaboration with Charles Vacanti’s lab at Brigham and Women’s Hospital, Harvard University, Masayuki Yamato’s lab at Tokyo Women’s Medical University, and the laboratories for Genomic Reprogramming, Pluripotent Stem Cell Studies, and Organogenesis and Neurogenesis at the RIKEN CDB.