Project description:Mutations in presenilin 1 (PSEN1) cause a familiar form of Alzheimer's disease (AD). We have obtained skin biopsies from two individuals carrying PSEN1 exon9 deletion and reprogrammed skin fibroblasts into induced pluripotent stem cells (iPSCs). To get controls, we have corrected PSEN1 exon9 deletion by CRISPR/Cas9 technique. Since astrocytes play role in AD pathogenesis, we further differentiated iPSCs into astrocytes. We ran RNA sequencing analysis to compare our iPSC-derived astrocytes with previously published data on human astrocytes and to identify genes and pathways affected by PSEN1 exon 9 deletion.
Project description:It remains controversial whether the routes from differentiated cells to iPSCs are related to the reverse order of normal developmental processes or independent of them. Here, we generated iPSCs from mouse astrocytes by three (Oct3/4, Klf4 and Sox2 (OKS)), two (OK), or four (OKS plus c-Myc) factors. Sox1, a neural stem cell (NSC)-specific transcription factor, is transiently upregulated during reprogramming and Sox1-positive cells become iPSCs. The upregulation of Sox1 is essential for OK-induced reprogramming. Genome-wide analysis revealed that the gene expression profile of Sox1-expressing intermediate-state cells resembles that of NSCs. Furthermore, the intermediate-state cells are able to generate neurospheres, which can differentiate into both neurons and glial cells. Remarkably, during MEF reprogramming, neither Sox1 upregulation nor an increase in neurogenic potential occurs. Thus, astrocytes are reprogrammed through an NSC-like state, suggesting that reprogramming partially follows the retrograde pathway of normal developmental processes. To investigate the gene expression profile of intermediate-state cells during astrocyte reprogramming, we performed genome-wide gene expression analysis in five samples; starting astrocytes, intermediate-state cells expressing Sox1-GFP, NSCs, iPSCs established from astrocytes, and iPSCs established from MEFs (iPS-MEF-Ng-20D-17) that had previously been reported (Okita, K. et al. Nature 448: 313-317 (2007)). Two (NSCs, iPSCs from astrocytes and MEFs) or three (astrocytes, intermediate-state cells) biological replicates were prepared for microarray samples. Total RNA was extracted with an RNeasy kit (Qiagen). cDNA synthesis and transcriptional amplification were performed using 50-100 ng of total RNA with the GeneChip WT PLUS Reagent Kit (Affymetrix). Fragmented and biotin-labeled cDNA targets were hybridized to GeneChip Mouse Gene 1.0 ST arrays (Affymetrix) according to the manufacturerâ??s protocol. Hybridized arrays were scanned using an Affymetrix GeneChip Scanner.
Project description:Down syndrome (trisomy 21) is the most common viable chromosomal disorder with intellectual impairment and several other developmental abnormalities. Here, we report the generation and characterization of induced pluripotent stem cells (iPSCs) derived from monozygotic twins discordant for trisomy 21 in order to eliminate the effects of the variability of genomic background. The alterations observed by genetic analysis at the iPSC level and at first approximation in early development illustrate the developmental disease transcriptional signature of Down syndrome. Moreover, we observed an abnormal neural differentiation of Down syndrome iPSCs in vivo when formed teratoma in NOD-SCID mice, and in vitro when differentiated into neuroprogenitors and neurons. These defects were associated with changes in the architecture and density of neurons, astroglial and oligodendroglial cells together with misexpression of genes involved in neurogenesis, lineage specification and differentiation. Furthermore, we provide novel evidence that dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A (DYRK1A) on chromosome 21 likely contribute to these defects. Importantly, we found that targeting DYRK1A pharmacologically or by shRNA results in a considerable correction of these defects. mRNA-seq profiling of iPS cells (4 euploid and 3 trisomy 21) derived from fibroblasts of monozygotic twins discordant for trisomy 21
Project description:Down syndrome (trisomy 21) is the most common viable chromosomal disorder with intellectual impairment and several other developmental abnormalities. Here, we report the generation and characterization of induced pluripotent stem cells (iPSCs) derived from monozygotic twins discordant for trisomy 21 in order to eliminate the effects of the variability of genomic background. The alterations observed by genetic analysis at the iPSC level and at first approximation in early development illustrate the developmental disease transcriptional signature of Down syndrome. Moreover, we observed an abnormal neural differentiation of Down syndrome iPSCs in vivo when formed teratoma in NOD-SCID mice, and in vitro when differentiated into neuroprogenitors and neurons. These defects were associated with changes in the architecture and density of neurons, astroglial and oligodendroglial cells together with misexpression of genes involved in neurogenesis, lineage specification and differentiation. Furthermore, we provide novel evidence that dual-specificity tyrosine-(Y)-phosphorylation regulated kinase 1A (DYRK1A) on chromosome 21 likely contribute to these defects. Importantly, we found that targeting DYRK1A pharmacologically or by shRNA results in a considerable correction of these defects. aCGH profiling of iPS cells derived from fibroblasts of monozygotic twins discordant for trisomy 21
Project description:The pupose of this study is to explore the mitophagy related transcriptome profiling of the astrocytes differentiated from POLG patient iPSCs compared to the astrocytes generated from healthy control iPSCs.
Project description:Individuals with Down syndrome (DS, Ts21) have impaired neurogenesis during development. Using Ts21 human induced pluripotent stem cells (iPSCs) and isogenic controls, we carried out single cell RNA-sequencing of Ts21 interneuron progenitors .
Project description:Compare single cell transcriptomes of control and USH1B patient iPSC-derived retinal organoids to elucidate disease mechanisms of Usher syndrome type IB (USH1B). USH1B patient fibroblasts were collected at Great Ormond Street Hospital (GOSH) and reprogrammed to iPSCs. Control and patient iPSCs differentiated in vitro to generate retinal organoids and collected at 35wks. Sequencing was performed at GENEWIZ (Azenta life sciences) on a Illumina NovaSeq system. Data aligned to the human genome UCSC hg38 using cellranger package.
Project description:Astrocytes, the most abundant glial cell type in the brain, are underrepresented in traditional cortical organoid models due to the delayed onset of cortical gliogenesis. Here, we introduce a novel glia-enriched cortical organoid model that exhibits accelerated astrogliogenesis. We demonstrated that induction of a gliogenic switch in a subset of progenitors enabled rapid derivation of astroglial cells, which account for 25-31% of the cell population within eight to ten weeks of differentiation. Intracerebral transplantation of these organoids reliably generated a diverse repertoire of cortical neurons and anatomical subclasses of human astrocytes. Spatial transcriptome profiling identified layer-specific expression patterns among distinct subclasses of astrocytes within the organoid transplants. Using an in vivo acute neuroinflammation model, we identified a subpopulation of astrocytes that rapidly activates proinflammatory pathways upon cytokine stimulation. Additionally, we demonstrated that CD38 signaling plays a crucial role in mediating metabolic and mitochondrial stress in reactive astrocytes. This model provides a robust platform for investigating human astrocyte function.
Project description:We characterized the gene expression by Hierarchical Clustering and one-matrix clustering in hESC, day 12 progenitors, day 25-day 27, day82 differentiated hypothalamic neurons from hESCs and day 45 neurons derived from iPSCs generated from controls (2 independent) and BBS (Bardet-Biedl Syndrome, 3 independent) subjects.
Project description:Compare transcriptomes of control and USH1B patient iPSC-derived retinal pigment epithelium (RPE) to elucidate disease mechanisms of Usher syndrome type IB (USH1B). USH1B patient fibroblasts were collected at Great Ormond Street Hospital (GOSH) and reprogrammed to iPSCs. Control and patient iPSCs differentiated in vitro to generate retinal pigment epithelium (RPE) and collected for RNA-seq at 24 week. Sequencing was performed at University College London (UCL) Genomics on a NovaSeq 6000 system. Data aligned to the human genome UCSC hg38 using RNA-STAR 2.5.2b.