Recent advances in reprogramming technology do not bypass the ethical challenge of embryo sacrifice. Induced pluripotent stem cell (iPS) research has been and almost certainly will continue to be conducted within the context of embryo sacrifice. If human embryos have moral status as human beings, then participation in iPS research renders one morally complicit in their destruction; if human emb...

This update discusses what is known regarding embryonic and adult tissue-derived pluripotent stem cells, including the mechanisms underlying self-renewal without senescence, differentiation in multiple cell types both in vitro and in vivo, and future potential clinical uses of such stem cells. In Section I, Dr. Lansdorp reviews the structure and function of telomerase, the enzyme that restores ...

Pluripotent stem cells are defined by their capacity to differentiate into all three tissue layers that comprise the body. Chimera formation, generated by stem cell transplantation to the embryo, is a stringent assessment of stem cell pluripotency. However, the ability of human pluripotent stem cells (hPSCs) to form embryonic chimeras remains in question. Here we show using a stage-matching app...

Pluripotent embryonic stem cells are undifferentiated cells capable of proliferation and self-renewal and have the capacity to differentiate into all somatic cell types and the germ line. They provide an in vitro model of early embryonic differentiation and are a useful means for targeted manipulation of the genome. Pluripotent stem cells in the chick have been derived from stage X blastoderms ...

Human pluripotent stem cells can in principle be used as a source of any differentiated cell type for disease modelling, drug screening, toxicology testing or cell replacement therapy. Type I diabetes is considered a major target for stem cell applications due to the shortage of primary human beta cells. Several protocols have been reported for generating pancreatic progenitors by in vitro diff...

Human embryonic stem cells have unique value for regenerative medicine, as they are capable of differentiating into a broad variety of cell types. Therefore, defining the signalling pathways that control early cell fate decisions of pluripotent stem cells represents a major task. Moreover, modelling the early steps of embryonic development in vitro may provide the best approach to produce cell ...

Human disease animal models are absolutely invaluable tools for our understanding of mechanisms involved in both physiological and pathological processes. By studying various genetic abnormalities in these organisms we can get a better insight into potential candidate genes responsible for human disease development. To this point a mouse represents one of the most used and convenient species fo...

In this study, we aimed to elucidate the effects and mechanism of action of valproic acid on hepatic differentiation from human induced pluripotent stem cell-derived hepatic progenitor cells. Human induced pluripotent stem cells were differentiated into endodermal cells in the presence of activin A and then into hepatic progenitor cells using dimethyl sulfoxide. Hepatic progenitor cells were ma...