Human embryonic germ cell derivatives express a broad range of developmentally distinct markers and proliferate extensively in vitro

Human pluripotent stem cells (hPSCs) have been derived from the inner cell mass cells of blastocysts (embryonic stem cells) and primordial germ cells of the developing gonadal ridge (embryonic germ cells). Like their mouse co unterparts, hPSCs can be maintained in culture in an undifferentiated state and, upon differentiation, generate a wide variety of cell types. Embryoid body (EB) formation is a requisite step in the process of in vitro differe ntiation of these stem cells and has been used to derive neurons and glia, vascular endothelium, hematopoietic cells, cardiomyocytes, and glucose-resp onsive insulin-producing cells from mouse PSCs. EBs generated from human em bryonic germ cell cultures have also been found to contain a wide variety o f cell types, including neural cells, vascular endothelium, muscle cells, a nd endodermal derivatives. Here, we report the isolation and culture of cel ls from human EBs as well as a characterization of their gene expression du ring growth in several different culture environments. These heterogeneous cell cultures are capable of robust and long-term [>70 population doublings (PD)] proliferation in culture, have normal karyotypes, and can be cryopre served, clonally isolated, and stably transfected. Cell cultures and clonal lines retain a broad pattern of gene expression including simultaneous exp ression of markers normally associated with cells of neural, vascular/hemat opoietic. muscle, and endoderm lineages. The growth and expression characte ristics of these EB-derived cells suggest that they are relatively uncommit ted precursor or progenitor cells. EB-derived cells may be suited to studie s of human cell differentiation and may play a role in future transplantati on therapies.