Assembly of embryonic and extraembryonic stem cells to mimic embryogenesis in vitro

TLDR

Pluripotent embryonic stem cells can differentiate into any adult cell type, but their aggregates fail to recapitulate embryonic architecture in culture. The study tests whether mouse ESCs together with trophoblast stem cells can recapitulate normal embryonic development. ESCs and TSCs were combined in an extracellular matrix culture to form ETS‑embryos. The ETS‑embryos resembled normal embryos, specifying mesoderm and primordial germ cells at the embryonic–extraembryonic boundary, and provide a genetically tractable tool for studying mammalian embryogenesis. Published in Science, issue p.

Abstract

In vitro embryogenesis Pluripotent embryonic stem cells (ESCs) can differentiate into any adult cell type; however, aggregates of these cells do not mimic embryonic architecture when grown in culture. To see whether mouse ESCs and their extraembryonic counterparts, trophoblast stem cells (TSCs), can recapitulate normal development, Harrison et al. combined ESCs and TSCs in an extracellular matrix culture (see the Perspective by Pera). The resultant “ETS-embryos” displayed considerable resemblance to normal embryos, even specifying mesoderm and primordial germ cells at the boundary between embryonic and extraembryonic compartments. These ETS-embryos are a genetically tractable tool for studying mammalian embryogenesis. Science , this issue p. eaal1810 ; see also p. 137