Implantation initiation of self-assembled embryo-like structures generated using three types of mouse blastocyst-derived stem cells

Spatially ordered embryo-like structures self-assembled from blastocyst-derived stem cells can be generated to mimic embryogenesis in vitro. However, the assembly system and developmental potential of such structures needs to be further studied. Here, we devise a nonadherent-suspension-shaking system to generate self-assembled embryo-like structures (ETX-embryoids) using mouse embryonic, trophoblast and extra-embryonic endoderm stem cells. When cultured together, the three cell types aggregate and sort into lineage-specific compartments. Signaling among these compartments results in molecular and morphogenic events that closely mimic those observed in wild-type embryos. These ETX-embryoids exhibit lumenogenesis, asymmetric patterns of gene expression for markers of mesoderm and primordial germ cell precursors, and formation of anterior visceral endoderm-like tissues. After transplantation into the pseudopregnant mouse uterus, ETX-embryoids efficiently initiate implantation and trigger the formation of decidual tissues. The ability of the three cell types to self-assemble into an embryo-like structure in vitro provides a powerful model system for studying embryogenesis.

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No genome or transcriptome sequencing data was used in this study, so no computer code about data preparation was available in this article. Data Policy information about availability of data All manuscripts must include a data availability statement. This statement should provide the following information, where applicable: -Accession codes, unique identifiers, or web links for publicly available datasets -A list of figures that have associated raw data -A description of any restrictions on data availability Source data for single-cell quantitative PCR experiments (Fig. 1h, 5g, 5i, 5j, 6d-g and 6i; Supplementary Fig. 9f, 9g, 10a and 10b) and the gene list with corresponding sequences ( Supplementary Fig. 10a) have been provided in Supplementary Data1. Qualifications of the data (Fig. 1i,2h,2i,3k,4c,4f,5e and 5f;Supplementary Fig. 2d,3c,4g,4h,8d and 12f) and embryo transplantation data (Fig. 7b, 7c, 7m and 7n; Supplementary Fig. 11f, 12a) have been provided in Source Data. The data supporting the findings of this study are available from the corresponding author on reasonable request.

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The subcellular localization of the proteins analyzed in this study has been previously reported in mouse embryo/stem cell studies.
Oct4 Authentication p53-/-, Lamc1-/-and Nodal-/-mouse ES cells were authenticated by sequencing. Cells were maintained in conditions to preserve stem cell character and prevent differentiation. Plates were inspected for morphological evidence of differentiation and plates with differentiated cells were discarded. Furthermore, cell identities were confirmed routinely by immunoflourescence marker expressions.

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Policy information about studies involving animals; ARRIVE guidelines recommended for reporting animal research Laboratory animals CD1 and 129 mice were obtained from Beijing Vital River Laboratory Animal Technology Co., Ltd. Actin-GFP mice were obtained from Shaorong Gao's Laboratory in Tongji University. All mice were maintained in specific pathogen-free (SPF) conditions with a 12-hour dark / 12-hour light cycle between 06:00 and 18:00 in a temperature controlled room (22 ± 2 ) with free access to 6 nature research | reporting summary

October 2018
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