Scientists from the Genome Institute of Singapore (GIS) have put forward a novel explanation for the pluripotency of embryonic stem (ES) cells. Their groundbreaking explanation opens new doors for understanding how stem cells create specific cell types, fundamental knowledge that will drive changes and improvements in the therapeutic and translational usage of stem cells. A better understanding of ES cells could help advance the development of treatments for diseases such as diabetes, Parkinson's disease, and Huntington's disease. The work, published in the journal Cell Stem Cell, was led by Dr Bing Lim, Senior Group Leader of the Stem Cell and Developmental Biology department at the GIS, and Kyle Loh, GIS student from Dr Lim's lab.
By re-examining current data with a fresh eye, Lim and Loh were able to suggest a novel paradigm that may resolve the 30-year-old mystery behind pluripotency. The prevailing model of stem cell pluripotency suggests that stem cell genes active in ES cells prevent these stem cells from turning into specific cell types. This model accounts for how ES cells can remain undifferentiated, but is unable to explain convincingly the ability of stem cells to create any bodily cell type. Lim and Loh suggest that, contrary to current thinking, individual stem cell genes do not completely suppress differentiation, but instead actively direct ES cells to produce particular bodily cell types. In their new paradigm, Lim and Loh propose that the activation of a combination of such stem cell genes within ES cells is what enables ES cells to create any bodily cell type.
Pluripotency refers to the ability of ES cells to differentiate into all bodily cell types. ES cells can potentially create, on demand, any cell type that clinicians or scientists need for therapeutic, biotechnological, or research purposes. Hence, the cells are currently used as a source of specialized cell types used in cell replacement therapies. An understanding of how ES cells are able to produce all these cell types is of intense pragmatic and theoretical interest.