Integrins have long been known to have a role in adhesion of neural stem cells within the neuroepithelium, but little is known about their role in regulating stem cell behaviour through signalling. We aimed to investigate the effect of integrin-beta 1 signalling (itgb1) on these cells by transfection of a constitutively active itgb1. This creates a heterogenous pattern of expression allowing the study of cell-autonomous and non-cell autonomous effects.
Integrin signalling regulates the expansion of neuroepithelial progenitors and neurogenesis via Wnt7a and Decorin.
Specimen part
View SamplesThe developmental potential of human pluripotent stem cells suggests that they can produce disease-relevant cell types for biomedical research. However, substantial variation has been reported among pluripotent cell lines, which could affect their utility and clinical safety. Such cell-line specific differences must be better understood before one can confidently use embryonic stem (ES) or induced pluripotent stem (iPS) cells in translational research. Towards this goal we have established genome-wide reference maps of DNA methylation and gene expression for 20 previously derived human ES lines and 12 human iPS cell lines, and we have measured the in vitro differentiation propensity of these cell lines. This resource enabled us to assess the epigenetic and transcriptional similarity of ES and iPS cells and to predict the differentiation efficiency of individual cell lines. The combination of assays yields a scorecard for quick and comprehensive characterization of pluripotent cell lines.
Reference Maps of human ES and iPS cell variation enable high-throughput characterization of pluripotent cell lines.
Sex, Cell line
View SamplesCommercial brewing yeast strains are exposed to a number of potential stresses including oxidative stress. The aim of this investigation was to measure the physiological and transcriptional changes of yeast cells during full-scale industrial brewing processes with a view to determining the environmental factors influencing the cells oxidative stress response. Cellular antioxidant levels were monitored throughout an industrial propagation and fermentation and microarray analysis was employed to determine transcriptional changes in antioxidant-encoding and other stress response genes. The greatest increase in cellular antioxidants and transcription of antioxidant-encoding genes occurred as the rapidly fermentable sugars glucose and fructose were depleted from the growth medium (wort) and the cell population entered the stationary phase. The data suggest that, contrary to expectation, the oxidative stress response is not influenced by changes in the dissolved oxygen concentration of wort but is initiated as part of a general stress response to growth-limiting conditions, even in the absence of oxygen. A mechanism is proposed to explain the changes in antioxidant response observed in yeast during anaerobic fermentation. The results suggest that the yeast cell does not experience oxidative stress, per se, during industrial brewery handling. This information may be taken into consideration when setting parameters for industrial brewery fermentation.
The oxidative stress response of a lager brewing yeast strain during industrial propagation and fermentation.
Age
View SamplesThree different progenitor cell subsets in subcutaneous and visceral adipose tissues derived from 5 obese patients were subjected to AmpliSeq transcriptome profiling. Transcriptomic profiles were analyzed to compare progenitor cell subsets and the impact of subcutaneous and visceral adipose tissue location. Overall design: Transcriptomic profiling of 3 different progenitor cell types in subcutaneous and visceral adipose tissues derived from 5 obese patients (3X2X5=30 samples).
Lobular architecture of human adipose tissue defines the niche and fate of progenitor cells.
Subject
View SamplesRetinopathy of prematurity (ROP) is a disorder of the developing retina of preterm infants. ROP can lead to blindness due to abnormal angiogenesis that is the result of suspended vascular development and vaso-obliteration leading to severe retinal stress and hypoxia. We tested the hypothesis that a combined treatment with two human progenitor populations, the CD34+ cells, bone marrow-derived, and the endothelial colony-forming cells (ECFCs) synergistically protected the developing retinal vasculature in a murine model of ROP, the oxygen-induced retinopathy (OIR)., CD34+ cells alone, ECFCs alone, or a combination thereof were injected intravitreally at either P5 or P12 and pups were euthanized at P17. Retinas from OIR mice injected with ECFCs or the combined treatment revealed formation of the deep vascular plexus (DVP) while still in hyperoxia, with normal appearing connections between the superficial vascular plexus (SVP) and the DVP. The combination therapy prevented aberrant retinal neovascularization and was more effective anatomically and functionally at rescuing the ischemia phenotype than either cell type alone. The beneficial effect of the cell combination was the result of their ability to orchestrate an acceleration of vascular development and more rapid ensheathment of pericytes on the developing vessels.
Progenitor cell combination normalizes retinal vascular development in the oxygen-induced retinopathy (OIR) model.
Specimen part, Disease, Disease stage, Treatment
View SamplesAnalysis of gene expression in pathologically confirmed glioblastoma (GBM) samples. These data were used to test a classifier that was generated to distinguish GBM tumor samples with loss of neurofibromin 1 (NF1) function
A machine learning classifier trained on cancer transcriptomes detects NF1 inactivation signal in glioblastoma.
Sex, Age, Specimen part
View SamplesAs part of a study of the role of the aryl hydrocarbon receptor (Ahr) in maintenance and senescence of hematopoietic stem cells (HSC), global gene expression profiling was done with HSC isolated from 18-month-old Ahr-knockout and wild-type mice. HSC from aged AhR-KO mice had changes in expression of many genes related to HSC maintenance, consistent with the phenotype observed in aging Ahr-KO mice: decreased survival rate, splenomegaly, increased circulating white blood cells, hematopoietic cell accumulation in tissues, anemia, increased numbers of stem/progenitor and lineage-committed cells in bone marrow, decreased erythroid progenitor cells in bone marrow, and decreased self-renewal capacity of HSC.
Conditional deletion of Ahr alters gene expression profiles in hematopoietic stem cells.
No sample metadata fields
View SamplesLiver injury results in rapid regeneration through hepatocyte proliferation and hypertrophy. However, after acute severe injury, such as acetaminophen poisoning, effective regeneration may fail. We investigated how senescence underlies this regenerative failure. In human acute liver disease, and murine models, p21-dependent hepatocellular senescence was proportionate to disease severity and was associated with impaired regeneration. In an acetaminophen injury model a transcriptional signature associated with the induction of paracrine senescence is observed within twenty four hours, and is followed by one of impaired proliferation. In genetic models of hepatocyte injury and senescence we observed transmission of senescence to local uninjured hepatocytes. Spread of senescence depended upon macrophage derived TGFß1 ligand. In acetaminophen poisoning inhibition of TGFß receptor 1 (TGFßR1) improved survival. TGFßR1 inhibition reduced senescence and enhanced liver regeneration even when delivered after the current therapeutic window. This mechanism, in which injury induced senescence impairs regeneration, is an attractive therapeutic target for acute liver failure. Overall design: RNA-seq analysis was performed on a total of 24 samples extracted from murine liver, post hepatic injury induced by acetaminophen administration. Transcriptional profiles were from replicate samples generated at defined timepoints - 12, 24, 36, 48 and 72 hours post injury. Replicate samples were generated from 4 individual animals sacrificed at each timepoint, and compared to a control cohort of 4 animals not subjected to acetaminophen treatment.
TGFβ inhibition restores a regenerative response in acute liver injury by suppressing paracrine senescence.
Specimen part, Cell line, Subject, Time
View SamplesIn order to gain insight into the molecular pathogenesis of the myelodysplastic syndromes (MDS), we performed global gene expression profiling and pathway analysis on the hematopoietic stem cells (HSC) of 183 MDS patients as compared with the HSC of 17 healthy controls. The most significantly deregulated pathways in MDS include interferon signaling, thrombopoietin signaling and the Wnt pathway. Among the most significantly deregulated gene pathways in early MDS are immunodeficiency, apoptosis and chemokine signaling, whereas advanced MDS is characterized by deregulation of DNA damage response and checkpoint pathways. We have identified distinct gene expression profiles and deregulated gene pathways in patients with del(5q), trisomy 8 or 7/del(7q). Patients with trisomy 8 are characterized by deregulation of pathways involved in the immune response, patients with 7/del(7q) by pathways involved in cell survival, whilst patients with del(5q) show deregulation of integrin signaling and cell cycle regulation pathways. This is the first study to determine deregulated gene pathways and ontology groups in the HSC of a large group of MDS patients. The deregulated pathways identified are likely to be critical to the MDS HSC phenotype and give new insights into the molecular pathogenesis of this disorder thereby providing new targets for therapeutic intervention.
Deregulated gene expression pathways in myelodysplastic syndrome hematopoietic stem cells.
Specimen part, Disease
View SamplesIn order to gain insight into the poorly understood pathophysiology of the myelodysplastic syndromes (MDS), we have determined the gene expression profiles of the CD34+ cells of 55 MDS patients using the Affymetrix GeneChip U133 Plus2.0 platform
Gene expression profiles of CD34+ cells in myelodysplastic syndromes: involvement of interferon-stimulated genes and correlation to FAB subtype and karyotype.
No sample metadata fields
View Samples