The potential safety issues related to the acquisition of common genomic aberrations in hPSC cultures are well-recognized, but these risks have not been evaluated for sporadic mutations. Here, we explore whether a sporadic mutation that spontaneously arose in a hESC culture consisting of a single-copy deletion of chr17p13.1 would confer a survival advantage to the mutant cells. Compared to wild-type cells with two normal copies of the chr17p13.1 region, the mutant cells displayed a selective advantage when exposed to stressful conditions, and retained a higher percentage of pluripotent cells after two weeks of in vitro differentiation. Knockdown of TP53, which is a gene encompassed by the deleted region, in wild-type cells mimicked the chr17p13.1 deletion phenotype. RNA sequencing analysis showed differential expression of genes in pathways related to proliferation and differentiation. Thus, phenotypic implications of sporadic mutations must be taken into consideration before using the hPSC for clinical applications. Overall design: Triplicate cDNA libraries of two mutant WA09 lines with a single-copy deletion of chr17p13.1, and two wild-type WA09 lines, for a total of 12 libraries were sequenced using Illumina HiSeq 2500. The sequence reads were mapped to hg19 reference genome and hits that passed quality filters were analyzed for differential expression.
Spontaneous Single-Copy Loss of TP53 in Human Embryonic Stem Cells Markedly Increases Cell Proliferation and Survival.
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View SamplesNeural stem cells (NSC) derived from human parthenogenic stem cells (hpSC) have been observed to show stronger positive functional effects than hpSC-derived dopaminergic neuron precursors (DAP) in treatment of induced Parkinson Disease in animal models. RNAseq of the two types of cells were normalized and analyzed to compare gene expression profiles. Overall design: cDNA library of hpsC, NSC and DAP triplicates were sequenced using Illumina HiSeq 2000. The sequence reads were mapped to hg19 reference genome and hits that passed quality filters were analyzed for differential expression.
Proof of concept studies exploring the safety and functional activity of human parthenogenetic-derived neural stem cells for the treatment of Parkinson's disease.
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Increased risk of genetic and epigenetic instability in human embryonic stem cells associated with specific culture conditions.
Sex, Specimen part, Cell line
View SamplesThe self-renewal and differentiation capacities of human pluripotent stem cells (hPSCs) make them good sources of cells for cell transplantation therapy, drug development, and studies of cellular differentiation and development. However, the large numbers of cells necessary for many of these applications require extensive expansion of hPSC cultures, a process that has been associated with applications require extensive expansion of hPSC cultures, a process that has been associated with genetic and epigenetic alterations. We have performed a systematic study over more than 100continuous passages to identify characteristics of culture conditions (including passage method, substrate, and media type) that influence the genetic and epigenetic stability and the phenotypic characteristics of hPSCs. The predominant effects we observed were increased genetic instability with enzymatic passage, higher cell proliferation with feeder-free substrate, and variations among cultures in global gene expression and DNA methylation with time in culture. We observed recurrent duplications in two genomic regions that have been noted in earlier studies to be hotspots for duplication in hPSCs, as well as a previously unreported recurrent deletion of the tumor suppressor gene TP53 in all but one of the long-term culture conditions; the exception was the condition using mechanical passaging on feeder layers. The deletion of TP53 is associated with decreased mRNA expression of TP53, as well as alterations in the expression of several other genes in the TP53 pathway, which taken together indicate a decrease in the function of the TP53 pathway. Our results highlight the need for careful assessment of effects of culture conditions on cells intended for clinical therapies.
Increased risk of genetic and epigenetic instability in human embryonic stem cells associated with specific culture conditions.
Sex, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Recurrent variations in DNA methylation in human pluripotent stem cells and their differentiated derivatives.
Sex, Specimen part, Disease, Cell line, Subject
View SamplesHuman pluripotent stem cells (hPSCs) are potential sources of cells for modeling disease and development, drug discovery, and regenerative medicine. However, it is important to identify factors that may impact the utility of hPSCs for these applications. In an unbiased analysis of 205 hPSC and 130 somatic samples, we identified hPSC-specific epigenetic and transcriptional aberrations in genes subject to X chromosome inactivation (XCI) and genomic imprinting, which were not corrected during directed differentiation. We also found that specific tissue types were distinguished by unique patterns of DNA hypomethylation, which were recapitulated by DNA demethylation during in vitro directed differentiation. Our results suggest that verification of baseline epigenetic status is critical for hPSC-based disease models in which the observed phenotype depends on proper XCI or imprinting, and that tissue-specific DNA methylation patterns can be accurately modeled during directed differentiation of hPSCs, even in the presence of variations in XCI or imprinting.
Recurrent variations in DNA methylation in human pluripotent stem cells and their differentiated derivatives.
Sex, Specimen part, Cell line, Subject
View SamplesSympathetic neurons of SCG (Superior Cervical Ganglia) send axonal projections either along the external carotid arteries to innervate the salivary glands, or along the internal carotid arteries to the lacrimal and pineal glands, the eye, blood vessels and skin of the head, and the mucosa of the oral and nasal cavities. Previous studies using Wnt1Cre and R26R have defined the neural crest and mesodermal origins of vascular smooth muscle in the heart outflow tract and great vessels, although not specifically of the segments that are relevant for the projections of the SCG neurons. The third pharyngeal arch arteries are lined by neural crest-derived smooth muscle, and consequently, their derivatives, including the entirety of the external carotid arteries and only the base of the internal carotid arteries, also have a neural crest origin. In contrast, the dorsal aortae are lined by smooth muscle that is mesodermal in origin, and as a result, the internal carotid arteries from just above their origination from the common carotid arteries have a mesoderm-derived smooth muscle layer. To address the possibility that guidance cues for SCG neurons are selectively expressed by the external carotid vs. the internal carotid arteries, we isolated these segments of the vasculature from mouse embryos at E13.5 and extracted RNA to screen microarrays for differentially expressed genes.
Endothelins are vascular-derived axonal guidance cues for developing sympathetic neurons.
No sample metadata fields
View SamplesHuman umbilical cord Whartons jelly stem cells (WHJSC) are gaining attention as a possible clinical source of mesenchymal stem cells for use in cell therapy and tissue engineering due to their high accessibility, expansion potential and plasticity. However, the cell viability changes that are associated to sequential cell passage of these cells are not known. In this analysis, we have identified the gene expression changes that are associated to cell passage in WHJSC.
Evaluation of the cell viability of human Wharton's jelly stem cells for use in cell therapy.
Specimen part
View SamplesCompare the behaviour of two populations of non-hematopoetic stem cells (MSC and MAPC) isolated from human bone marrow. The effect of culture conditions on the behaviour of MSC was also characterised by isolating MSC and then culturing the cells for 96h in MAPC growth conditions
Validation of COL11A1/procollagen 11A1 expression in TGF-β1-activated immortalised human mesenchymal cells and in stromal cells of human colon adenocarcinoma.
Age, Specimen part
View SamplesX-chromosome inactivation (XCI) provides a dosage compensation mechanism where, in each female cell, one of the two X chromosomes is randomly silenced. However, some genes on the inactive X chromosome and outside the pseudoautosomal regions escape from XCI and are expressed from both alleles (escapees). We investigated XCI at single-cell resolution combining deep single cellRNA sequencing with whole-genome sequencing to examine allelic-specific expression in 935 primary fibroblast and 48 lymphoblastoid single cells from five female individuals. In this framework we integrated an original method to identify and exclude doublets of cells. In fibroblast cells, we have identified 55 genes as escapees including five novel escapee genes. Moreover, we observed that all genes exhibit a variable propensity to escape XCI in each cell and cell type and that each cell displays a distinct expression profile of the escapee genes. A metric, the Inactivation Score—defined as the mean of the allelic expression profiles of the escapees per cell—enables us to discover a heterogeneous and continuous degree of cellular XCI with extremes represented by “inactive” cells, i.e., cells exclusively expressing the escaping genes from the active X chromosome and “escaping” cells expressing the escapees from both alleles. We found that this effect is associated with cell-cycle phases and, independently, with the XIST expression level, which is higher in the quiescent phase (G0). Single-cell allele-specific expression is a powerful tool to identify novel escapees in different tissues and provide evidence of an unexpected cellular heterogeneity of XCI. Overall design: Single-cell RNA seq study on 935 human fibroblasts and 48 lymphoblastoid cells from 5 female individuals, in order to investigate the X chromosome nactivation mechanism on a single cell level and to identify escapee genes
Single cell transcriptome in aneuploidies reveals mechanisms of gene dosage imbalance.
Specimen part, Subject
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