In human, endoderm is induced in two waves, with the first being the extra-embryonic primitive endoderm (PrE), otherwise known as hypoblast, induced during blastocyst development, and the second being gastrulation-stage… Click to show full abstract
In human, endoderm is induced in two waves, with the first being the extra-embryonic primitive endoderm (PrE), otherwise known as hypoblast, induced during blastocyst development, and the second being gastrulation-stage definitive endoderm (DE). The PrE gives rise to the primary and secondary yolk sac, and has supportive functions during pregnancy for nutrient provision, with descendants of this extra-embryonic lineage also playing a role in embryonic patterning. As in DE specification, we recently found that PrE could be induced in vitro by Wnt and Nodal-related signaling, but that the critical difference was in the pluripotent starting point for differentiation. Thus, blastocyst-like naïve human pluripotent stem cells retain the unique capacity to differentiate into PrE cultures, a cell type resembling the pre-implantation hypoblast. The PrE cells could then be expanded as stable naïve extra-embryonic endoderm (nEnd) cell lines, capable of indefinite self-renewal. Here, we describe detailed protocols to differentiate naïve pluripotent stem cells into PrE and then expand the cultures as nEnd, including descriptions of morphology, passaging technique, and troubleshooting.
               
Click one of the above tabs to view related content.