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GSE60803
Homo sapiens
12 Downloadable Samples
Affymetrix Human Gene 1.1 ST Array (hugene11st)
Description
In vitro expansion of adult human islet cells is an attractive solution for the shortage of tissue for cell replacement therapy of type 1 diabetes. Using a lineage tracing approach, we have demonstrated that -cell-derived (BCD) cells rapidly dedifferentiate in culture and can proliferate for up to 16 population doublings. Dedifferentiation is associated with changes resembling epithelial-mesenchymal transition (EMT). The WNT pathway has been shown to induce EMT and plays key roles in regulating replication and differentiation in many cell types. Here we show that BCD cell dedifferentiation is associated with -catenin translocation into the nucleus and activation of the WNT pathway. Inhibition of -catenin expression in expanded BCD cells using short hairpin RNA resulted in growth arrest, mesenchymal-epithelial transition, and redifferentiation, as judged by activation of -cell gene expression. Furthermore, inhibition of -catenin expression synergized with redifferentiation induced by a combination of soluble factors, as judged by an increase in the number of C-peptide-positive cells. Simultaneous inhibition of the WNT and NOTCH pathways also resulted in a synergistic effect on redifferentiation. These findings, which were reproducible in cells derived from multiple human donors, suggest that inhibition of the WNT pathway may contribute to a therapeutically applicable way for generation of functional insulin-producing cells following ex-vivo expansion.
Publication Title
Redifferentiation of adult human β cells expanded in vitro by inhibition of the WNT pathway.
Sample Metadata Fields
Specimen part, Treatment, Subject
View Samples- Homo sapiens
- 9 Downloadable Samples
IlluminaHiSeq2500
Description
We applied RNA-seq analysis to human islet cells, received from 3 independent donors, treated with either redifferentiation cocktail + ARX shRNA, or redifferentiation cocktail + control shRNA or left untreated. Overall design: Examination of the effect of ARX inhibition on redifferentiation of ß-cell-derived (BCD) cells
Publication Title
Redifferentiation of expanded human islet β cells by inhibition of ARX.
Sample Metadata Fields
No sample metadata fields
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Three induced pluripotent stem (iPS) cell lines were generated from pancreatic BCD (beta-cell-derived cells). One iPS cell clone was derived from pancreatic non-beta cells. We used microarrays to study the gene expression profiles of beta-iPSCs, and compared the expression of genes in their somatic parental cells and other ES and iPS cells.
Publication Title
Epigenetic memory and preferential lineage-specific differentiation in induced pluripotent stem cells derived from human pancreatic islet beta cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Homo sapiens
- 11 Downloadable Samples
- Affymetrix Human Gene 1.0 ST Array (hugene10st)
Description
Expansion of beta cells from the limited number of adult human islet donors is an attractive prospect for increasing cell availability for cell therapy of diabetes. However, while evidence supports the replicative capacity of adult beta cells in vivo, attempts at expanding human islet cells in tissue culture resulted in loss of beta-cell phenotype. Using a genetic lineage-tracing approach we have provided evidence for massive proliferation of beta-cell-derived (BCD) cells within these cultures. Expansion involves dedifferentiation resembling epithelial-mesenchymal transition (EMT). Epigenetic analyses indicate that key beta-cell genes maintain a partially open chromatin structure in expanded BCD cells, although they are not transcribed. Here we report that BCD cells can be induced to redifferentiate by a combination of soluble factors. The redifferentiated cells express beta-cell genes, store insulin in typical secretory vesicles, and release it in response to glucose. The redifferentiation process involves mesenchymal-epithelial transition, as judged from changes in gene expression. Moreover, inhibition of the EMT effector SLUG using shRNA results in stimulation of redifferentiation. BCD cells also give rise at a low rate to cells expressing other islet hormones, suggesting transition through an islet progenitor-like stage during redifferentiation. These findings suggest that ex-vivo expansion of adult human islet cells is a promising approach for generation of insulin-producing cells for transplantation, as well as basic research, toxicology studies, and drug screening.
Publication Title
Insulin-producing cells generated from dedifferentiated human pancreatic beta cells expanded in vitro.
Sample Metadata Fields
Specimen part
View Samples- Rattus norvegicus
- 56 Downloadable Samples
- Affymetrix Rat Genome 230 2.0 Array (rat2302)
Description
Cytokines have been shown to play a key role in the destruction of beta cells. In the rat insulinoma cell line (INS-1ab) overexpressing pancreatic duodenum homeobox 1 (Pdx1) increases sensitivity to Interleukin 1b (IL-1b). To elucidate mechanisms of action underlying Pdx1 driven potentiation of beta-cell sensitivity to IL-1, we performed a microarray analysis of INS-1ab cells with and without Pdx1 overexpression exposed to IL-1 between 2h and 24h.
Publication Title
Divalent metal transporter 1 regulates iron-mediated ROS and pancreatic β cell fate in response to cytokines.
Sample Metadata Fields
Cell line, Time
View Samples- Arabidopsis thaliana
- 12 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Although bodyguard (bdg), lacerata (lcr) and fiddlehead (fdh) mutations affect three unrelated genes, they trigger similar effects, i.e. ectopic organ fusion, increase of cuticle permeability. After performing cutin and wax analyses on these Arabidopsis thaliana mutants, which did not coincide with the putative enzyme functions, we hypothesised that these mutations trigger a complex response which may be visible at the transcriptional level.
Publication Title
Dissection of the complex phenotype in cuticular mutants of Arabidopsis reveals a role of SERRATE as a mediator.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 144 Downloadable Samples
- Affymetrix HT HG-U133+ PM Array Plate (hthgu133pluspm)
Description
As part of a larger effort to provide proof-of-concept in vitro only risk assessments, we have developed a suite of high throughput assays for key readouts in the p53 DNA damage response toxicity pathway: DSB DNA damage (p-H2AX), permanent chromosomal damage (micronuclei; MN), p53 activation, p53 transcriptional activity, and cell fate (cell cycle arrest, apoptosis,MN). Dose-response studies were performed with these protein and cell fate assays, together with whole genome transcriptomics, for three prototype chemicals: etoposide (ETP), quercetin (QUE) and methyl methanesulfonate (MMS). Data were collected in a human cell line expressing wild-type p53 (HT1080) and results were confirmed in a second p53 competent cell line (HCT 116). At chemical concentrations causing similar increases in p53 protein expression, p53-mediated protein expression and cellular processes showed substantial chemical-specific differences. These chemical-specific differences in the p53 transcriptional response appear to be determined by augmentation of the p53 response by co-regulators. More importantly, dose-response data for each of the chemicals indicates that the p53 transcriptional response does not prevent MN induction at low concentrations. In fact, the no observed effect levels (NOELs) and benchmark doses (BMDs) for MN induction were less than or equal to those for p53-mediated gene transcription regardless of the test chemical, indicating that p53s post-translational responses may be more important than transcriptional activation in the response to low dose DNA damage. This effort demonstrates the process of defining key assays required for a pathway-based, in vitro-only risk assessment, using the p53-mediated DNA damage response pathway as a prototype.
Publication Title
Profiling dose-dependent activation of p53-mediated signaling pathways by chemicals with distinct mechanisms of DNA damage.
Sample Metadata Fields
Specimen part, Cell line
View Samples- Mus musculus
- 22 Downloadable Samples
- Ion Torrent Proton
Description
We designed a study to investigate immunoediting of an epithelial cancer genome using wildtype and immunodeficient mice, NGS, and analytical pipelines to process and analyze the data. We carried out experiments with wildtype and immunodeficient RAG1-/- mice with transplanted tumors and analyzed longitudinal samples with respect to the genomic landscape and the immunophenotypes of the tumors. Finally, we performed also experiments with anti-PD-L1 antibodies and show how the activation of the PD1-PD-L1 axis modulates immunoediting. MC38 cells were subcutaneously injected into wild-type C57Bl/6 and immunodeficient Rag1-/- mice. Samples were taken at predefined time points and subjected to detailed analysis, including FACS, exome sequencing, RNA sequencing and SNP arrays. Overall design: Samples were taken at predifined time points, in triplicates and subjected to RNA sequencing using Ion Torrent Proton
Publication Title
Targeting immune checkpoints potentiates immunoediting and changes the dynamics of tumor evolution.
Sample Metadata Fields
Subject, Time
View Samples- Arabidopsis thaliana
- 40 Downloadable Samples
- Illumina HiSeq 2000
Description
40 QC single cells multiplexed using the CEL-Seq protocol Overall design: 40 cells from the QC
Publication Title
Quantification of cell identity from single-cell gene expression profiles.
Sample Metadata Fields
Age, Subject
View Samples- Arabidopsis thaliana
- 10 Downloadable Samples
- Affymetrix Arabidopsis ATH1 Genome Array (ath1121501)
Description
Leaf development has been monitored chiefly by following anatomical markers. Analysis of transcriptome dynamics during leaf maturation revealed multiple expression patterns that rise or fall with age or that display age specific peaks. These were used to formulate a digital differentiation index (DDI), based on a set of selected markers with informative expression during leaf ontogeny. The leaf-based DDI reliably predicted the developmental state of leaf samples from diverse sources and was independent of mitotic cell division transcripts or propensity of the specific cell type. When calibrated by informative root markers, the same algorithm accurately diagnosed dissected root samples. We used the DDI to characterize plants with reduced activities of multiple CINCINNATA (CIN)-TCP growth regulators. These plants had giant curled leaves made up of small cells with abnormal shape, low DDI scores and low expression of mitosis markers, depicting the primary role of CIN-TCPs as promoters of differentiation. Delayed activity of several CIN-TCPs resulted in abnormally large but flat leaves with regular cells. The application of DDI has therefore portrayed the CIN-TCPs as heterochronic regulators that permit the development of a flexible and robust leaf form through an ordered and protracted maturation schedule.
Publication Title
A protracted and dynamic maturation schedule underlies Arabidopsis leaf development.
Sample Metadata Fields
No sample metadata fields
View Samples