Project description:The placenta is a transient but important multifunctional organ crucial for healthy pregnancy for both mother and fetus. Nevertheless, limited access to human placenta samples and the paucity of a proper in vitro model system has hampered our understanding of the mechanisms underlying early human placental development and placenta-associated pregnancy complications. To overcome these constraints, we established a simple procedure with a short-term treatment of bone morphogenetic protein 4 (BMP4) in trophoblast stem cell culture medium (TSCM) to convert human primed pluripotent stem cells (PSCs) to trophoblast stem-like cells (TSLCs). These TSLCs show not only comparable morphology and gene expression profile to bona fide human trophoblast stem cells (TSCs) but also long-term self-renewal capacity with bipotency that allows the cells to differentiate into extravillous trophoblasts (EVT) and syncytiotrophoblasts (ST). These indicate that TSLCs are equivalent to genuine human TSCs. Our data suggest a straightforward approach to make human TSCs directly from pre-existing primed PSCs and provide a valuable opportunity to study human placenta development and pathology even from patients with placenta-related diseases.
Project description:Human naive pluripotent stem cells have unrestricted lineage potential. Underpinning this property, naive cells are thought to lack chromatin-based lineage barriers. However, this assumption has not been tested. Here, we apply multi-omics to comprehensively define the chromatin-associated proteome, histone post-translational modifications and transcriptome of human naive and primed pluripotent stem cells. Integrating the chromatin-bound proteome and histone modification data sets reveals differences in the relative abundance and activities of distinct chromatin modules, identifying a strong enrichment of Polycomb Repressive Complex 2 (PRC2)-associated H3K27me3 in naive pluripotent stem cell chromatin. Single-cell approaches and human blastoid models reveal that PRC2 activity acts as a chromatin barrier restricting the differentiation of naive cells towards the trophoblast lineage, and inhibiting PRC2 promotes trophoblast fate induction and cavity formation. Our results establish that human naive pluripotent stem cells are not epigenetically unrestricted, but instead possess chromatin mechanisms that oppose the induction of alternative cell fates.
Project description:Trophoblast stem cells (TSC) have recently been derived from human embryos, and early first trimester placenta; however, aside from ethical challenges, the unknown disease potential of these cells limits their scientific utility. We have previously established a BMP4-based two-step protocol for differentiation of primed human pluripotent stem cells (hPSC) into functional trophoblast; however, those trophoblast could not be maintained in a self-renewing TSC-like state. Here, we use the first step from this protocol, followed by a switch to a newly-developed TSC media, to derive bona-fide TSC. We show that these cells resemble placenta- and naïve hPSC-derived TSC, based on their transcriptome, as well as in vitro and in vivo differentiation potential. We conclude that primed hPSC can be used to generate functional TSC, through a simple protocol which can be applied to a widely-available set of existing hPSC, including induced pluripotent stem cells derived from patients with known birth outcomes.
Project description:Trophoblast stem cells (TSC) have recently been derived from human embryos, and early first trimester placenta; however, aside from ethical challenges, the unknown disease potential of these cells limits their scientific utility. We have previously established a BMP4-based two-step protocol for differentiation of primed human pluripotent stem cells (hPSC) into functional trophoblast; however, those trophoblast could not be maintained in a self-renewing TSC-like state. Here, we use the first step from this protocol, followed by a switch to a newly-developed TSC media, to derive bona-fide TSC. We show that these cells resemble placenta- and naïve hPSC-derived TSC, based on their transcriptome, as well as in vitro and in vivo differentiation potential. We conclude that primed hPSC can be used to generate functional TSC, through a simple protocol which can be applied to a widely-available set of existing hPSC, including induced pluripotent stem cells derived from patients with known birth outcomes.
Project description:Naïve human pluripotent stem cells (hPSCs) provide a unique experimental platform of cell fate decisions during pre-implantation development, but their lineage potential remains incompletely characterized. As naïve hPSCs share transcriptional and epigenomic signatures with trophoblast cells, it has been proposed that the naïve state may have enhanced predisposition for differentiation along this extraembryonic lineage. Here we examined the trophoblast potential of isogenic naïve and primed hPSCs. We found that naïve hPSCs can directly give rise to human trophoblast stem cells (hTSCs) and undergo further differentiation into both extravillous and syncytiotrophoblast. In contrast, primed hPSCs do not support hTSC derivation, but give rise to non-self-renewing cytotrophoblasts in response to BMP4. Global transcriptome and chromatin accessibility analyses indicate that hTSCs derived from naïve hPSCs acquire features of pre-implantation trophectoderm. The derivation of hTSCs from naïve hPSCs will enable elucidation of early mechanisms that govern normal human trophoblast development and associated pathologies.
Project description:Naïve human pluripotent stem cells (hPSCs) provide a unique experimental platform of cell fate decisions during pre-implantation development, but their lineage potential remains incompletely characterized. As naïve hPSCs share transcriptional and epigenomic signatures with trophoblast cells, it has been proposed that the naïve state may have enhanced predisposition for differentiation along this extraembryonic lineage. Here we examined the trophoblast potential of isogenic naïve and primed hPSCs. We found that naïve hPSCs can directly give rise to human trophoblast stem cells (hTSCs) and undergo further differentiation into both extravillous and syncytiotrophoblast. In contrast, primed hPSCs do not support hTSC derivation, but give rise to non-self-renewing cytotrophoblasts in response to BMP4. Global transcriptome and chromatin accessibility analyses indicate that hTSCs derived from naïve hPSCs acquire features of pre-implantation trophectoderm. The derivation of hTSCs from naïve hPSCs will enable elucidation of early mechanisms that govern normal human trophoblast development and associated pathologies.