An aggregation of human embryonic and trophoblast stem cells reveals the role of trophectoderm on epiblast differentiation

Abstract

The interactions between extra-embryonic tissues and embryonic tissues are crucial to ensure proper early embryo development. However, the understanding of the crosstalk between the embryonic tissues and extra-embryonic tissues is lacking, mainly due to ethical restrictions, difficulties in obtaining natural human embryos, and lack of appropriate in vitro models. Here by aggregating human embryonic stem cells (hESCs) with human trophoblast stem cells (hTSCs), we revealed the hESCs robustly self-organized into a unique asymmetric structure which the primitive streak (PS) like cells exclusively distributed at the distal end to the TS-compartment, and morphologically flattened cells, presumed to be the extra-embryonic mesoderm cells (EXMC) like cells, were induced at the proximal end to hTSCs. Our study revealed two potential roles of extra-embryonic trophectoderm in regulating the proper PS formation during gastrulation and EXMCs induction from the human epiblast.

ISRIB facilitates the co‐culture of human trophoblast stem cells and embryonic stem cells

“…Using our previously established 3D co‐culture system (hESCs and hTSCs aggregates, ETAs), 18 we further explored whether ESM + nTSM can facilitate the spatial organisation of hESCs and hTSCs. We compared the developmental efficiency of ETAs in indicated co‐culture mediums, including ESM, TSM, ESM + TSM‐3C and ESM + nTSM.…”

“…The generation of hESCs and hTSCs aggregates (ETA) was performed following our previously published protocol. 18 The AggreWell™ 400 plates were rinsed with 1 mL rinsing solution (Stem Cell Technologies, 07010) per well. Then, the plates were centrifuged for 5 min at 2000 g and incubated with rinsing solution at room temperature for 20 min.…”

“…The generation of hESCs and hTSCs aggregates (ETA) was performed following our previously published protocol 18 . The AggreWell™ 400 plates were rinsed with 1 mL rinsing solution (Stem Cell Technologies, 07010) per well.…”

“…Using our previously established 3D co-culture system (hESCs and hTSCs aggregates, ETAs), 18 to AgreeWell™ 400 with 14,400 cells per well, and hTSCs were seeded 24 h later with 80,000 cells per well, at which time was defined as Day 0 (Figure 7A). The ETAs were cultured in indicated mediums and changed half daily.…”