Differentiation and maturation of oligodendrocytes in human three-dimensional neural cultures
Ontology highlight
ABSTRACT: We report a method for deriving oligodendrocyte lineage cells from human pluripotent stem cells (hPSCs) in three-dimensional (3D) culture called human oligodendrocyte spheroids (hOLS). To characterize oligodendrocyte-lineage cells in hOLS, we isolated O4+ cells by immunopanning and performed deep single cell RNA sequencing. We sequenced 295 cells and compared their profiles to unsorted cells isolated from primary human fetal cortex, primary human adult cortex, and hCS. Clustering of all cells using the t-distributed stochastic neighbor embedding (tSNE) approach revealed a distinct populations of SOX10+ oligodendrocytes, within which the O4+ cells derived from hOLS clustered most closely to oligodendrocyte progenitor cells (OPCs) and mature oligodendrocytes from the primary human adult cortical tissue. Additionally, subpopulations of OPCs, newly formed oligodendrocytes, and myelinating oligodendrocytes derived were observed in the hOLS-derived cluster. To further assess the state of oligodendrocyte-lineage cells in hOLS, we performed a Monocle analysis which revealed a spectrum of oligodendrocyte-lineage stages in hOLS ranging from dividing cells that closely resembled primary OPCs to mature cells that closely resembled primary oligodendrocytes.
Project description:We report the generation of induced oligodendrocyte precursor cells (iOPCs) by direct lineage conversion. Forced expression of the three transcription factors Sox10, Olig2 and Zfp536 was sufficient to convert mouse and rat fibroblasts into iOPCs with morphologies and gene expression signatures that resemble OPCs. We compared the global gene expression pattern of iOPCs, fibroblasts, primary OPCs from the neonatal rat brain, and their differentiated progeny. We purified iOPCs by O4 immunopanning three weeks after infection and extracted total RNA. Acutely isolated rat cortical OPCs were either used directly for RNA extraction or expanded in mitogen-containing media for 24h before switching into differentiation medium, lacking PDGF/NT-3 and containing T3. Cells were harvested for microarray analysis 3 and 6 days after induction of differentiation.
Project description:Stem cell biology has garnered much attention due to its potential to impact human health through disease modeling and cell replacement therapy. This is especially pertinent to myelin-related disorders such as multiple sclerosis and leukodystrophies where restoration of normal oligodendrocyte function could provide an effective treatment. Progress in myelin repair has been constrained by the difficulty in generating pure populations of oligodendrocyte progenitor cells (OPCs) in sufficient quantities. Pluripotent stem cells theoretically provide an unlimited source of OPCs but significant advances are currently hindered by heterogeneous differentiation strategies that lack reproducibility. Here we provide a platform for the directed differentiation of pluripotent mouse epiblast stem cells (EpiSCs) through a defined series of developmental transitions into a pure population of highly expandable OPCs in ten days. These OPCs robustly differentiate into myelinating oligodendrocytes both in vitro and in vivo. Our results demonstrate that pluripotent stem cells can provide a pure population of clinically-relevant, myelinogenic oligodendrocytes and offer a tractable platform for defining the molecular regulation of oligodendrocyte development, drug screening, and potential cell-based remyelinating therapies. 6 total samples were analyzed. Pluripotent epiblast stem cells (EpiSCs) were differentiated to patterned neural rosettes, oligodendrocyte progenitor cells (OPCs), and oligodendrocytes. OPCs and oligodedrocytes were analyzed at two separate passages (3 and 11).
Project description:Adult oligodendrocyte progenitors (aOPCs) share with their neonatal counterpart (nOPC) the ability to give rise to myelinating oligodendrocytes, but they also display unique functional features. This study addresses the molecular mechanisms underlying the intrinsic differences between these two populations. Using RNA-sequencing and unbiased histone proteomics analysis performed on PDGFRa+ OPCs sorted from a reporter mouse, we define the unique transcriptome and histone marks of aOPCs. We describe the higher levels of genes related to lipid metabolism and myelin sheath, and lower expression of genes related to cycle and proliferation in aOPCs compared to nOPCs. We also identify greater levels of activating H4K8ac and repressive H4K20me3 histone marks in aOPCs compared to nOPCs, and increased occupancy of H4K8ac mark at chromatin locations corresponding to oligodendrocyte-specific genes. Pharmacological inhibition of histone acetylation in neonatal O4+OPCs (nO4+OPCs) and adult O4+OPCs (aO4+OPCs) followed by RNA-sequencing showed a moderate change in the transcriptome of these cells resulting in the decrease of proliferation capacity in aO4+OPCs but not nO4+OPCs. Pharmacological inhibition of H4K20me3 mark was not sufficient to change the transcriptome or functional properties of nO4+OPCs and aO4+OPC. Overall, this study identifies histone acetylation as key in regulating the proliferation of aO4+OPCs.
Project description:Oligodendrocytes undergo extensive changes as they differentiate from progenitors into myelinating cells. To better understand the; molecular mechanisms underlying this transformation, we performed a comparative analysis using gene expression profiling of A2B5+; oligodendrocyte progenitors and O4+ oligodendrocytes. Cells were sort-purified ex vivo from postnatal rat brain using flow cytometry. Using Affymetrix microarrays, 1707 transcripts were identified with a more than twofold increase in expression inO4+oligodendrocytes. Many genes required for oligodendrocyte differentiation were upregulated in O4+ oligodendrocytes, including numerous genes encoding; myelin proteins. Transcriptional changes included genes required for cell adhesion, actin cytoskeleton regulation, and fatty acid and; cholesterol biosynthesis. At the O4+ stage, there was an increase in expression of a novel proline-rich transmembrane protein (Prmp). Localized to the plasma membrane, Prmp displays adhesive properties that may be important for linking the extracellular matrix to the; actin cytoskeleton. Together, our results highlight the usefulness of this discovery-driven experimental strategy to identify genes relevant; to oligodendrocyte differentiation and myelination. Experiment Overall Design: Whole brain dissociates were prepared from one litter of 10 male postnatal day 7 rat pups for each of the 5 A2B5 bioligcal replicates and the 4 O4+ bioligical replicates. Total RNA was extracted from single A2B5+ and single O4+ cells sorted directly from postnatal day7 rat whole brain dissociates using flow cytometry.
Project description:Oligodendrocytes undergo extensive changes as they differentiate from progenitors into myelinating cells. To better understand the molecular mechanisms underlying this transformation, we performed a comparative analysis using gene expression profiling of A2B5+ oligodendrocyte progenitors and O4+ oligodendrocytes. Cells were sort-purified ex vivo from postnatal rat brain using flow cytometry. Using Affymetrix microarrays, 1707 transcripts were identified with a more than twofold increase in expression inO4+oligodendrocytes. Many genes required for oligodendrocyte differentiation were upregulated in O4+ oligodendrocytes, including numerous genes encoding myelin proteins. Transcriptional changes included genes required for cell adhesion, actin cytoskeleton regulation, and fatty acid and cholesterol biosynthesis. At the O4+ stage, there was an increase in expression of a novel proline-rich transmembrane protein (Prmp). Localized to the plasma membrane, Prmp displays adhesive properties that may be important for linking the extracellular matrix to the actin cytoskeleton. Together, our results highlight the usefulness of this discovery-driven experimental strategy to identify genes relevant to oligodendrocyte differentiation and myelination. Keywords: develepmental stage, oligodendrocyte differentiation
Project description:Neurons and oligodendrocytes communicate to regulate oligodendrocyte development and ensure appropriate axonal myelination. Here, we show that Glycerophosphodiester phosphodiesterase 2 (GDE2) encodes a neuronal pathway that promotes oligodendrocyte maturation through the release of soluble neuronally-derived factors. Mice lacking global or neuronal GDE2 expression have reduced mature oligodendrocytes and myelin proteins but retain normal numbers of oligodendrocyte precursor cells (OPCs). WT OPCs cultured in conditioned medium (CM) from Gde2 null (Gde2KO) neurons exhibit delayed maturation, recapitulating in vivo phenotypes. Gde2KO neurons show robust reduction in canonical Wnt signaling and genetic activation of Wnt signaling in Gde2KO neurons rescues in vivo and in vitro oligodendrocyte maturation. Phosphacan, a known stimulant of OL maturation, is reduced in CM from Gde2KOneurons but is restored when Wnt signaling is activated. These studies identify GDE2 control of Wnt signaling as a neuronal pathway that signals to oligodendroglia to promote oligodendrocyte maturation.
Project description:Cell-based therapies for myelin disorders, such as multiple sclerosis and leukodystrophies, require technologies to generate functional oligodendrocyte progenitor cells. Here we describe direct conversion of mouse embryonic and lung fibroblasts to ‘induced’ oligodendrocyte progenitor cells (iOPCs) using sets of either eight or three defined transcription factors. iOPCs exhibit a bipolar morphologyical and global gene expression profile molecular features consistent with bona fide OPCs. They can be expanded in vitro for at least five passages while retaining the ability to differentiate into induced multiprocessed oligodendrocytes. When transplanted to hypomyelinated mice, iOPCs are capable of ensheathing host axons and generating compact myelinmyelinating axons both in vitro and in vivo. Lineage conversion of somatic cells to expandable iOPCs provides a strategy to study the molecular control of oligodendrocyte lineage identity and may facilitate neurological disease modeling and autologous remyelinating therapies. 6 total samples were analyzed. MEFs were either untreated or infected with inducible lentiviral vectors containing the open reading frames of transcription factors. Samples were compared to bona fide OPCs.
Project description:Human fetal dissociates from 19-22 week gestational age were magnetically sorted for CD140a antigen. CD140a-defined OPCs were plated into serum free conditions and allowed to differentiate in the absence of growth factors or mitogens. RNA was extracted from cells immediately following isolation and every day for 4 days. To block differentiation, matched cells were cultured in the presence of PDGF-AA (10ng/ml). This treatment prevents the acquisition of O4-positive oligodendrocyte cell fate and delays MBP mRNA expression by human CD140a-sorted OPCs. 29 samples, 4 time points, 2 media conditions, at least three biological replicates per time point and media condition
Project description:Oligodendrocytes are generated from oligodendrocyte precursor cells (OPCs). Chd7 is ATP-dependent chromatin-remodeling enzyme. We performed microarray analysis to examine changes in gene expression between control and Chd7 knockdown OPCs. Results provide insight into the function of Chd7 in oligodendrocyte development.
Project description:Human fetal dissociates from 19-22 week gestational age were magnetically sorted for CD140a antigen. CD140a-defined OPCs were plated into serum free conditions and allowed to differentiate in the absence of growth factors or mitogens. RNA was extracted from cells immediately following isolation and every day for 4 days. To block differentiation, matched cells were cultured in the presence of PDGF-AA (10ng/ml). This treatment prevents the acquisition of O4-positive oligodendrocyte cell fate and delays MBP mRNA expression by human CD140a-sorted OPCs.