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Cell Oct 2019A single mouse blastomere from an embryo until the 8-cell stage can generate an entire blastocyst. Whether laboratory-cultured cells retain a similar generative capacity...
A single mouse blastomere from an embryo until the 8-cell stage can generate an entire blastocyst. Whether laboratory-cultured cells retain a similar generative capacity remains unknown. Starting from a single stem cell type, extended pluripotent stem (EPS) cells, we established a 3D differentiation system that enabled the generation of blastocyst-like structures (EPS-blastoids) through lineage segregation and self-organization. EPS-blastoids resembled blastocysts in morphology and cell-lineage allocation and recapitulated key morphogenetic events during preimplantation and early postimplantation development in vitro. Upon transfer, some EPS-blastoids underwent implantation, induced decidualization, and generated live, albeit disorganized, tissues in utero. Single-cell and bulk RNA-sequencing analysis revealed that EPS-blastoids contained all three blastocyst cell lineages and shared transcriptional similarity with natural blastocysts. We also provide proof of concept that EPS-blastoids can be generated from adult cells via cellular reprogramming. EPS-blastoids provide a unique platform for studying early embryogenesis and pave the way to creating viable synthetic embryos by using cultured cells.
Topics: Animals; Blastocyst; Cell Differentiation; Cell Line; Cell Lineage; Cells, Cultured; Cellular Reprogramming Techniques; Embryo Implantation; Female; Humans; Induced Pluripotent Stem Cells; Male; Mice; Mice, Inbred C57BL; Mice, Inbred ICR; Mouse Embryonic Stem Cells; Research Embryo Creation; Transcriptome
PubMed: 31626770
DOI: 10.1016/j.cell.2019.09.029 -
Cell Stem Cell Oct 2022Several in vitro models have been developed to recapitulate mouse embryogenesis solely from embryonic stem cells (ESCs). Despite mimicking many aspects of early...
Several in vitro models have been developed to recapitulate mouse embryogenesis solely from embryonic stem cells (ESCs). Despite mimicking many aspects of early development, they fail to capture the interactions between embryonic and extraembryonic tissues. To overcome this difficulty, we have developed a mouse ESC-based in vitro model that reconstitutes the pluripotent ESC lineage and the two extraembryonic lineages of the post-implantation embryo by transcription-factor-mediated induction. This unified model recapitulates developmental events from embryonic day 5.5 to 8.5, including gastrulation; formation of the anterior-posterior axis, brain, and a beating heart structure; and the development of extraembryonic tissues, including yolk sac and chorion. Comparing single-cell RNA sequencing from individual structures with time-matched natural embryos identified remarkably similar transcriptional programs across lineages but also showed when and where the model diverges from the natural program. Our findings demonstrate an extraordinary plasticity of ESCs to self-organize and generate a whole-embryo-like structure.
Topics: Animals; Embryo, Mammalian; Embryonic Development; Embryonic Stem Cells; Mice; Mouse Embryonic Stem Cells; Neurulation
PubMed: 36084657
DOI: 10.1016/j.stem.2022.08.013 -
Nature Protocols Dec 2023The interaction between embryonic and extraembryonic tissues is critical in natural mouse embryogenesis. Here, to enable such interaction in vitro, we describe a... (Review)
Review
The interaction between embryonic and extraembryonic tissues is critical in natural mouse embryogenesis. Here, to enable such interaction in vitro, we describe a protocol to assemble a complete mouse embryo model using mouse embryonic stem cells and induced embryonic stem cells to express Cdx2 (or trophoblast stem cells) and Gata4 to reconstitute the epiblast, extraembryonic ectoderm and visceral endoderm lineages, respectively. The resulting complete embryo models recapitulate development from embryonic day 5.0 to 8.5, generating advanced embryonic and extraembryonic tissues that develop through gastrulation to initiate organogenesis to form a head and a beating heart structure as well as a yolk sac and chorion. Once the required stem cell lines are stably maintained in culture, the protocol requires 1 day to assemble complete embryo models and a further 8 days to culture them until headfold stages, although structures can be collected at earlier developmental stages as required. This protocol can be easily performed by researchers with experience in mouse stem cell culture, although they will benefit from knowledge of natural mouse embryos at early postimplantation stages.
Topics: Mice; Animals; Germ Layers; Embryo, Mammalian; Endoderm; Embryonic Development; Embryonic Stem Cells
PubMed: 37821625
DOI: 10.1038/s41596-023-00891-y -
Cell Stem Cell May 2023Understanding the mechanisms of blastocyst formation and implantation is critical for improving farm animal reproduction but is hampered by a limited supply of embryos....
Understanding the mechanisms of blastocyst formation and implantation is critical for improving farm animal reproduction but is hampered by a limited supply of embryos. Here, we developed an efficient method to generate bovine blastocyst-like structures (termed blastoids) via assembling bovine trophoblast stem cells and expanded potential stem cells. Bovine blastoids resemble blastocysts in morphology, cell composition, single-cell transcriptomes, in vitro growth, and the ability to elicit maternal recognition of pregnancy following transfer to recipient cows. Bovine blastoids represent an accessible in vitro model for studying embryogenesis and improving reproductive efficiency in livestock species.
Topics: Pregnancy; Female; Cattle; Animals; Blastocyst; Trophoblasts; Embryo Implantation; Embryonic Development; Stem Cells; Cell Culture Techniques
PubMed: 37146582
DOI: 10.1016/j.stem.2023.04.003 -
Science (New York, N.Y.) Apr 2017Mammalian embryogenesis requires intricate interactions between embryonic and extraembryonic tissues to orchestrate and coordinate morphogenesis with changes in...
Mammalian embryogenesis requires intricate interactions between embryonic and extraembryonic tissues to orchestrate and coordinate morphogenesis with changes in developmental potential. Here, we combined mouse embryonic stem cells (ESCs) and extraembryonic trophoblast stem cells (TSCs) in a three-dimensional scaffold to generate structures whose morphogenesis is markedly similar to that of natural embryos. By using genetically modified stem cells and specific inhibitors, we show that embryogenesis of ESC- and TSC-derived embryos-ETS-embryos-depends on cross-talk involving Nodal signaling. When ETS-embryos develop, they spontaneously initiate expression of mesoderm and primordial germ cell markers asymmetrically on the embryonic and extraembryonic border, in response to Wnt and BMP signaling. Our study demonstrates the ability of distinct stem cell types to self-assemble in vitro to generate embryos whose morphogenesis, architecture, and constituent cell types resemble those of natural embryos.
Topics: Animals; Embryo Implantation; Embryo, Mammalian; Embryonic Development; Embryonic Stem Cells; Gastrulation; Germ Layers; In Vitro Techniques; Mesoderm; Mice; Models, Biological; Tissue Scaffolds; Trophoblasts; Wnt Signaling Pathway
PubMed: 28254784
DOI: 10.1126/science.aal1810 -
Nature Oct 2023The human embryo undergoes morphogenetic transformations following implantation into the uterus, but our knowledge of this crucial stage is limited by the inability to...
The human embryo undergoes morphogenetic transformations following implantation into the uterus, but our knowledge of this crucial stage is limited by the inability to observe the embryo in vivo. Models of the embryo derived from stem cells are important tools for interrogating developmental events and tissue-tissue crosstalk during these stages. Here we establish a model of the human post-implantation embryo, a human embryoid, comprising embryonic and extraembryonic tissues. We combine two types of extraembryonic-like cell generated by overexpression of transcription factors with wild-type embryonic stem cells and promote their self-organization into structures that mimic several aspects of the post-implantation human embryo. These self-organized aggregates contain a pluripotent epiblast-like domain surrounded by extraembryonic-like tissues. Our functional studies demonstrate that the epiblast-like domain robustly differentiates into amnion, extraembryonic mesenchyme and primordial germ cell-like cells in response to bone morphogenetic protein cues. In addition, we identify an inhibitory role for SOX17 in the specification of anterior hypoblast-like cells. Modulation of the subpopulations in the hypoblast-like compartment demonstrates that extraembryonic-like cells influence epiblast-like domain differentiation, highlighting functional tissue-tissue crosstalk. In conclusion, we present a modular, tractable, integrated model of the human embryo that will enable us to probe key questions of human post-implantation development, a critical window during which substantial numbers of pregnancies fail.
Topics: Female; Humans; Pregnancy; Bone Morphogenetic Proteins; Cell Differentiation; Embryo Implantation; Embryo, Mammalian; Embryoid Bodies; Embryonic Development; Germ Layers; Human Embryonic Stem Cells; Models, Biological; Transcription Factors; Pluripotent Stem Cells
PubMed: 37369347
DOI: 10.1038/s41586-023-06368-y -
Developmental Cell Feb 2021The development of mouse embryos can be partially recapitulated by combining embryonic stem cells (ESCs), trophoblast stem cells (TS), and extra-embryonic endoderm (XEN)...
The development of mouse embryos can be partially recapitulated by combining embryonic stem cells (ESCs), trophoblast stem cells (TS), and extra-embryonic endoderm (XEN) stem cells to generate embryo-like structures called ETX embryos. Although ETX embryos transcriptionally capture the mouse gastrula, their ability to recapitulate complex morphogenic events such as gastrulation is limited, possibly due to the limited potential of XEN cells. To address this, we generated ESCs transiently expressing transcription factor Gata4, which drives the extra-embryonic endoderm fate, and combined them with ESCs and TS cells to generate induced ETX embryos (iETX embryos). We show that iETX embryos establish a robust anterior signaling center that migrates unilaterally to break embryo symmetry. Furthermore, iETX embryos gastrulate generating embryonic and extra-embryonic mesoderm and definitive endoderm. Our findings reveal that replacement of XEN cells with ESCs transiently expressing Gata4 endows iETX embryos with greater developmental potential, thus enabling the study of the establishment of anterior-posterior patterning and gastrulation in an in vitro system.
Topics: Animals; Biomarkers; Cell Line; Cell Lineage; Embryo, Mammalian; Embryonic Stem Cells; Endoderm; Epithelial-Mesenchymal Transition; GATA4 Transcription Factor; Gastrulation; Induced Pluripotent Stem Cells; Mice; Morphogenesis; Primitive Streak; Signal Transduction
PubMed: 33378662
DOI: 10.1016/j.devcel.2020.12.004 -
Cell Stem Cell Jun 2021Human naive pluripotent cells can differentiate into extraembryonic trophectoderm and hypoblast. Here we describe a human embryo model (blastoid) generated by...
Human naive pluripotent cells can differentiate into extraembryonic trophectoderm and hypoblast. Here we describe a human embryo model (blastoid) generated by self-organization. Brief induction of trophectoderm leads to formation of blastocyst-like structures within 3 days. Blastoids are composed of three tissue layers displaying exclusive lineage markers, mimicking the natural blastocyst. Single-cell transcriptome analyses confirm segregation of trophectoderm, hypoblast, and epiblast with high fidelity to the human embryo. This versatile and scalable system provides a robust experimental model for human embryo research.
Topics: Blastocyst; Cell Differentiation; Cell Lineage; Embryo, Mammalian; Germ Layers; Humans; Stem Cells
PubMed: 33957081
DOI: 10.1016/j.stem.2021.04.031 -
Nature Mar 2021Limited access to embryos has hampered the study of human embryogenesis and disorders that occur during early pregnancy. Human pluripotent stem cells provide an...
Limited access to embryos has hampered the study of human embryogenesis and disorders that occur during early pregnancy. Human pluripotent stem cells provide an alternative means to study human development in a dish. Recent advances in partial embryo models derived from human pluripotent stem cells have enabled human development to be examined at early post-implantation stages. However, models of the pre-implantation human blastocyst are lacking. Starting from naive human pluripotent stem cells, here we developed an effective three-dimensional culture strategy with successive lineage differentiation and self-organization to generate blastocyst-like structures in vitro. These structures-which we term 'human blastoids'-resemble human blastocysts in terms of their morphology, size, cell number, and composition and allocation of different cell lineages. Single-cell RNA-sequencing analyses also reveal the transcriptomic similarity of blastoids to blastocysts. Human blastoids are amenable to embryonic and extra-embryonic stem cell derivation and can further develop into peri-implantation embryo-like structures in vitro. Using chemical perturbations, we show that specific isozymes of protein kinase C have a critical function in the formation of the blastoid cavity. Human blastoids provide a readily accessible, scalable, versatile and perturbable alternative to blastocysts for studying early human development, understanding early pregnancy loss and gaining insights into early developmental defects.
Topics: Blastocyst; Cell Culture Techniques; Cell Differentiation; Cell Line; Cell Lineage; Gene Expression Regulation, Developmental; Human Embryonic Stem Cells; Humans; Isoenzymes; Pluripotent Stem Cells; Protein Kinase C; Single-Cell Analysis; Transcriptome
PubMed: 33731924
DOI: 10.1038/s41586-021-03356-y -
Nature May 2018The blastocyst (the early mammalian embryo) forms all embryonic and extra-embryonic tissues, including the placenta. It consists of a spherical thin-walled layer, known...
The blastocyst (the early mammalian embryo) forms all embryonic and extra-embryonic tissues, including the placenta. It consists of a spherical thin-walled layer, known as the trophectoderm, that surrounds a fluid-filled cavity sheltering the embryonic cells . From mouse blastocysts, it is possible to derive both trophoblast and embryonic stem-cell lines , which are in vitro analogues of the trophectoderm and embryonic compartments, respectively. Here we report that trophoblast and embryonic stem cells cooperate in vitro to form structures that morphologically and transcriptionally resemble embryonic day 3.5 blastocysts, termed blastoids. Like blastocysts, blastoids form from inductive signals that originate from the inner embryonic cells and drive the development of the outer trophectoderm. The nature and function of these signals have been largely unexplored. Genetically and physically uncoupling the embryonic and trophectoderm compartments, along with single-cell transcriptomics, reveals the extensive inventory of embryonic inductions. We specifically show that the embryonic cells maintain trophoblast proliferation and self-renewal, while fine-tuning trophoblast epithelial morphogenesis in part via a BMP4/Nodal-KLF6 axis. Although blastoids do not support the development of bona fide embryos, we demonstrate that embryonic inductions are crucial to form a trophectoderm state that robustly implants and triggers decidualization in utero. Thus, at this stage, the nascent embryo fuels trophectoderm development and implantation.
Topics: Animals; Blastocyst; Bone Morphogenetic Protein 4; Cell Self Renewal; Ectoderm; Embryo Implantation; Embryonic Stem Cells; Female; Gene Expression Regulation, Developmental; Humans; Kruppel-Like Factor 6; Male; Mice; Morphogenesis; Nodal Protein; Transcriptome; Trophoblasts; Uterus
PubMed: 29720634
DOI: 10.1038/s41586-018-0051-0