Project description:Rat Extraembryonic Endoderm Precursor (XEN-P) cells resemble the nascent hypoblast of the blastocyst. Here we show that rat Multipotent Adult Progenitor Cell (rMAPC) lines derived from bone marrow (BM) exhibit salient nascent hypoblast characteristics. We could not identify cells with hypoblast features in rat BM, but they appeared after prolonged in vitro culture under rMAPC conditions. However, rMAPC culture conditions supported the very rapid isolation of new lines with nascent hypoblast features from rat blastocysts that were more homogenous than XEN-P cells isolated on feeders. The gene expression profile, growth factor requirement, Oct4 promoter methylation, and in vitro/vivo differentiation potential of cells isolated using rMAPC culture conditions from BM or blastocysts or XEN-P cells were highly similar. We conclude that the three cell populations have characteristics of hypoblast stem cells (HypoSC) and that rMAPC culture conditions support the isolation of XEN-P/HypoSC from the blastocyst and induction of HypoSC from BM. Comparison between bone marrow and blastocyst-derived Hypoblast Stem Cells (hypoSC) Three cell lines derived from bone marrow, three cell lines derived from blastocyst and one mesenchymal used, as control (for all of them 2 replicates)
Project description:Rat Extraembryonic Endoderm Precursor (XEN-P) cells resemble the nascent hypoblast of the blastocyst. Here we show that rat Multipotent Adult Progenitor Cell (rMAPC) lines derived from bone marrow (BM) exhibit salient nascent hypoblast characteristics. We could not identify cells with hypoblast features in rat BM, but they appeared after prolonged in vitro culture under rMAPC conditions. However, rMAPC culture conditions supported the very rapid isolation of new lines with nascent hypoblast features from rat blastocysts that were more homogenous than XEN-P cells isolated on feeders. The gene expression profile, growth factor requirement, Oct4 promoter methylation, and in vitro/vivo differentiation potential of cells isolated using rMAPC culture conditions from BM or blastocysts or XEN-P cells were highly similar. We conclude that the three cell populations have characteristics of hypoblast stem cells (HypoSC) and that rMAPC culture conditions support the isolation of XEN-P/HypoSC from the blastocyst and induction of HypoSC from BM.
Project description:Two phases of pluripotency, naïve and primed, have been captured in vitro and studied in details1. A third formative phase was recently proposed to exist between naïve and primed phases2. Formative pluripotency entails permissiveness for direct primordial germ cell (PGC) induction and competence for blastocyst chimeras, and is characterized by transcriptional and epigenetic features intermediate of naïve and primed pluripotency. To date, however, stable pluripotent stem cells (PSCs) harboring formative features haven’t been derived from early mammalian embryos. Here we develop a method which enabled the derivation and culture of stable formative-like embryonic stem cells (ESCs) from mouse blastocysts. Formative-like mouse ESCs share molecular features characteristic of early post-implantation epiblasts and are competent for PGC-like cell induction and blastocyst chimera formation. The same culture also supported the derivation of ESCs and transgene-free induced pluripotent stem cells (iPSCs) from horse blastocysts and fibroblasts, respectively. Horse ESCs/iPSCs transcriptionally resembled mouse formative cells, and could also be directly induced into PGC-like cells. Formative-like horse iPSCs could efficiently chimerize horse, mouse, goat, sheep and pig embryos. Stable formative-like PSCs will be invaluable for studying mammalian pluripotency, and our method may be broadly applicable for the derivation of PGC and chimera competent PSCs from other mammalian species.
Project description:Two phases of pluripotency, naïve and primed, have been captured in vitro and studied in details1. A third formative phase was recently proposed to exist between naïve and primed phases2. Formative pluripotency entails permissiveness for direct primordial germ cell (PGC) induction and competence for blastocyst chimeras, and is characterized by transcriptional and epigenetic features intermediate of naïve and primed pluripotency. To date, however, stable pluripotent stem cells (PSCs) harboring formative features haven’t been derived from early mammalian embryos. Here we develop a method which enabled the derivation and culture of stable formative-like embryonic stem cells (ESCs) from mouse blastocysts. Formative-like mouse ESCs share molecular features characteristic of early post-implantation epiblasts and are competent for PGC-like cell induction and blastocyst chimera formation. The same culture also supported the derivation of ESCs and transgene-free induced pluripotent stem cells (iPSCs) from horse blastocysts and fibroblasts, respectively. Horse ESCs/iPSCs transcriptionally resembled mouse formative cells, and could also be directly induced into PGC-like cells. Formative-like horse iPSCs could efficiently chimerize horse, mouse, goat, sheep and pig embryos. Stable formative-like PSCs will be invaluable for studying mammalian pluripotency, and our method may be broadly applicable for the derivation of PGC and chimera competent PSCs from other mammalian species.
Project description:Various culture systems have been used to derive and maintain human pluripotent stem cells (hPSCs), but they are inefficient in sustaining cloning and suspension expansion of hPSCs. Through systematically modulating Wnt and Activin/Nodal signaling, we developed a defined medium (termed AIC), which enables efficient cloning and long-term expansion of hPSCs (AIC-hPSCs) through single-cell passage on feeders, matrix or in suspension (25-fold expansion in 4 days) and maintains genomic stability of hPSCs over extensive expansion. Moreover, the AIC medium supports efficient derivation of hPSCs from blastocysts or somatic cells under feeder-free conditions. Compared to conventional-culture hPSCs, AIC-hPSCs have similar gene expression profiles but down-regulated differentiation genes and display higher metabolic activity. The AIC medium shows a good compatibility for suspension expansion of different hPSC lines. Our study provides a robust culture system for derivation, cloning and suspension expansion of high-quality hPSCs that benefits GMP production and processing of therapeutic hPSC products
Project description:Faithful embryogenesis requires the precise coordination between embryonic and extraembryonic tissues. Although embryonic and extraembryonic stem cells have been derived from several mammalian species including humans, they are cultured in different conditions, which makes it difficult to study their intercommunication. Here, by simultaneously activating FGF, TGF-β and WNT pathways, we derived stable pluripotent stem cells (PSCs), trophoblast stem cells (TSCs) and extraembryonic endoderm stem cells (XENs) from mouse blastocysts under the same condition (FTW). Co-culture of PSCs and XENs in the same environment uncovered, among other interactions, a previously unrecognized control of proliferation of epiblast cells by extraembryonic endoderm cells. FTW condition also supported de novo derivation of XENs from cynomolgus monkey and human blastocysts, and enabled setting up co-culture of human iPSCs and XENs. Crosspieces comparison revealed conserved and divergent processes and genes regulating XENs and ligand-receptor interactions between pluripotent and extraembryonic endoderm cells. Our study establishes a unique stem cell co-culture strategy to examine embryonic and extraembryonic lineage crosstalk during early mammalian development, and opens the door for developing more faithful in vitro models and differentiation protocols.
Project description:Faithful embryogenesis requires the precise coordination between embryonic and extraembryonic tissues. Although embryonic and extraembryonic stem cells have been derived from several mammalian species including humans, they are cultured in different conditions, which makes it difficult to study their intercommunication. Here, by simultaneously activating FGF, TGF-β and WNT pathways, we derived stable pluripotent stem cells (PSCs), trophoblast stem cells (TSCs) and extraembryonic endoderm stem cells (XENs) from mouse blastocysts under the same condition (FTW). Co-culture of PSCs and XENs in the same environment uncovered, among other interactions, a previously unrecognized control of proliferation of epiblast cells by extraembryonic endoderm cells. FTW condition also supported de novo derivation of XENs from cynomolgus monkey and human blastocysts, and enabled setting up co-culture of human iPSCs and XENs. Crosspieces comparison revealed conserved and divergent processes and genes regulating XENs and ligand-receptor interactions between pluripotent and extraembryonic endoderm cells. Our study establishes a unique stem cell co-culture strategy to examine embryonic and extraembryonic lineage crosstalk during early mammalian development, and opens the door for developing more faithful in vitro models and differentiation protocols.
Project description:Naive pluripotent embryonic stem cells (ESCs) and embryonic germ cells (EGCs) are derived from the preimplantation epiblast and primordial germ cells (PGCs), respectively. We investigated whether differences exist between ESCs and EGCs, in view of their distinct developmental origins. PGCs are programmed to undergo global DNA demethylation; however, we find that EGCs and ESCs exhibit equivalent global DNA methylation levels. Importantly, inhibition of Erk and Gsk3b by 2i conditions leads to pronounced reduction in DNA methylation in both cell types. This is driven by Prdm14 and is associated with downregulation of Dnmt3a and Dnmt3b. However, genomic imprints are maintained in 2i, and we report derivation of EGCs with intact genomic imprints. Collectively, our findings establish that culture in 2i instills a naive pluripotent state with a distinctive epigenetic configuration that parallels molecular features observed in both the preimplantation epiblast and nascent PGCs. EGC lines were derived from E8.5 mouse embryos using three different protocols: FCS+LIF on MEFs (FCS, n = 4)), FCS+LIF on MEFs for 48 hours followed by 2i+LIF (2is, n = 4), and direct derivation into 2i+LIF (2i, n = 4). ESC lines were derived in either FCS+LIF on MEFs or in 2i+LIF conditions and once established the cell lines were also switched between the two culture environments (n = 5 for each culture condition). All cell lines were derived from genetically identical embryos.
Project description:Multiple myeloma is hematologic malignancies result from clonal proliferation of plasma cells. Recently, increasing evidence supports the hypothesis that microenvironment cells play important roles in the proliferation, survival, and drug resistance of clonal plasma cells. The aim of this study is to culture stromal cells from bone marrow aspirates of patients with multiple myeloma, and to investigate expression profiles of bone marrow stromal cells and their relationships with the clinical characteristics of patients.