Morphogenetic and transcriptomic signature of syncytialization from human trophoblast stem cells

We reveal that STB which differentiated from hTSCs could recapitulate morphogenetic events that physiologically occur during human embryo implantation. STB could also recapitulate the genetic signature of trophoblast differentiation during implantation. It will provide a reliable model to investigate the syncytialization of trophoblast during implantation. Our discovery was potentially valuable in advancing not only our current understanding of implant progression but also paying the way to investigate recurrent implantation failure. Human trophoblast stem cells (hTSCs) were derived from human embryos and induced for the differentiation of extravillous trophoblast cells (EVT) and syncytiotrophoblast (STB). STB was cultured in Matrigel to mimic the morphogenesis of primary syncytialization in human embryos during implantation. To evaluate the similarity between syncytialization from hTSCs and syncytialization in human embryos, three-dimensional culture and immunofluorescence staining of STB, single-cell RNA sequencing, and culturing human embryos to the post-implantation stage were performed.