Project description:Endothelial colony-forming cells (ECFCs) have been reported as promising cells for regenerative medicine thanks to their angiorepair properties. Transcription factors are primary determinants of the functional capacity of the cells and TAL1 has been shown as a critical regulator of endothelial lineage in both development and adult life. However, only few (three) TAL1 targets have been identified so far in mouse and human endothelial cells. This microarray experiment, where TAL1 expression was knocked-down, was designed to identify TAL1-dependent genes in primary human endothelial stem/progenitor cells. ECFCs were isolated from three independent cord blood samples (n=3, biological replicates) and cultured in complete EGM-2 medium. The knockdown of TAL1 was induced by infection with lentiviruses expressing an anti-TAL1 shRNA. A scrambled shRNA was used as a negative control. Cells were then harvested for RNA extraction. DNA-free total RNA was isolated with RNeasy Mini Kit and hybridized to the Affymetrix Human Gene 1.0 ST gene expression microarray.
Project description:Endothelial progenitors represent one of the most promising cell-based strategies for vascular repair of ischemic tissue damage, including limb ischemia, myocardial infarction and stroke. We have shown that the transcription factor TAL1 regulates a transcription program that drives the migration and adhesion of ECFCs. Furthermore, treatment of ECFCs with the HDAC inhibitor TSA increases the expression of TAL1-dependent genes and promotes the migration, chemotaxis and adhesion of ECFCs. Finally, ex vivo treatment with TSA also improves the vascular repair properties of ECFCs in vivo when these cells are transplanted in a mouse model of hindlimb ischemia. The goal of this experiment was to test whether TSA treatment of ECFCs affect TAL1 genomic binding. TAL1 ChIP-sequencing was performed from ECFCs that have been treated or not TSA. As negative controls, we performed Mock-ChIP-seq from the same samples using normal IgG instead of the TAL1 antibody. Overall, we find that there is no change in TAL1 genomic binding in ECFCs upon TSA treatment.
Project description:Endothelial colony-forming cells (ECFCs) have been reported as promising cells for regenerative medicine thanks to their angiorepair properties. Transcription factors are primary determinants of the functional capacity of the cells and TAL1 has been shown as a critical regulator of endothelial lineage in both development and adult life. However, only few (three) TAL1 targets have been identified so far in mouse and human endothelial cells. This ChIP-seq experiment was designed to identify genome binding/occupancy of TAL1 by ChIP and high throughput sequencing in primary human endothelial stem/progenitor cells. TAL1 ChIP and IgG ChIP (negative control) were performed in crosslinked ECFCs derived from human umbilical cord blood.
Project description:The 9p21.3 genetic locus is a well-established risk factor for coronary artery disease (CAD), however there is much about its exact mechanism that is yet to be established. To explore the impact of the 9p21.3 CAD risk locus on gene expression within a pathologically relevant cell type the transcriptome profiles of 9p21.3 homozygous risk (HR), heterozygous (HET) and homozygous non-risk (HNR) genotypes were determined in primary human aortic smooth muscle cells (HAoSMC). Total RNA was isolated from 4 HR, 4 HET and 3 HNR primary cells and gene expression quantified using the Affymetrix Human Gene 1.0 ST array.
Project description:Our experiments have demonstrated that VEGF signalling is a critical component of oncolytic virus infection in tumor vasculature. This effect is in part mitigated by downstream activation of the master immunoloigcal transcriptional repressor known as PRD/BF1. To investigate the role of the VEGF-PRD/BF1 signalling axis in the context of oncolytic virus infection, we isolated the RNA from sub-confluent human umbilical vein endothelial cells treated under four conditions (siRNA Control, siRNA Control + WyTK-, siRNA Control + WyTK- + VEGF165 and siRNA PRD/BF1 + WyTK- + VEGF165. Using the RNA pooled from four experiments, the goal of this study was to determine the nature & fraction of genes repressed by VEGF in the context of infection, which could be rescued by PRD/BF1.
Project description:The study aimed to identify circular RNAs (circRNAs) commonly back-spliced to intronic region of different sets of endothelial cells (human cardiac microvascular endothelial cells (HCMEC), human aortic endothelial cells (HAoEC), human umbilical vein endothelial cells (HUVECs)) and to evaluate their overall expression and their expression compared to their respective host gene. Identified circRNAs were quality controlled by their detection in an additional exonuclease RNase R treated RNA-Seq dataset performed with RNA of HUVECs. CircRNAs were compared for overlapping detection between datasets and filtered by annotation for circRNAs back-spliced to intronic regions. Common endothelial intronic circRNAs candidates were compared to respective murine circRNAs stored in the circATLAS database. The prime candidate cZNF292 was functionally characterized in vivo and in vitro.
Project description:Physical factors can have major influences on the proliferation and differentiation fate of hematopoietic stem cells in culture. Recently, we demonstrated that cord blood CD34+ cells undergo accelerated and increased megakaryocyte differentiation when incubated at 39°C. In this study, we investigated in detail the impacts of mild hyperthermia on the kinetics of megakaryocyte differentiation, maturation, polyploidization and cell viability. The qualitative and quantitative effects on Mk differentiation were found to be rapidly induced, and optimization of the culture length at 39°C led to greater Mk yields. Mild hyperthermia did not promote endomitosis of cord blood-derived Mk, but rather led to a small reduction in the proportion of polyploid Mk. Moreover, it had little impact on viability but induced a significant shift in the proportion of cells undergoing apoptosis at 37°C to necrosis at 39°C. Finally, our results suggest that the effects on megakaryocyte differentiation could be the consequences of aberrant expression of key megakaryocyte transcription factors induced by mild hyperthermia. Experiment Overall Design: To define potential differences between megakaryocytes (Mk) derived at 37°C or 39°C, we compared their gene expression repertoire by micro-gene chip technology (Affymetrix GeneChip HG133A). Two independent experiments were carried out on Mk at 37 or 39°C. CD41a+ Mk issued from CB CD34+ cells were cultured for 7-days with TPO at 100 ng/ml and purified by positive magnetic selection using a CD41a-FITC monoclonal antibody (Immunotech, Marseille, France) and MACS columns according to manufacturerâs instructions (Miltenyi, Auburn, CA, USA) with a purity of >95%.
Project description:Human induced pluripotent stem cells (hIPSCs) represent a unique opportunity for regenerative medicine since they offer the prospect of generating unlimited quantities of cells for autologous transplantation as a novel treatment for a broad range of disorders. It is now known that primary iPS cells often carry genomic aberrations and these abnormality may compromise their possibility of clinical application. We analysed primary hIPSC lines derived from monoclonal human endothelial progenitor cell lines by array-based comparative genomic hybridisation.
Project description:Derivation and expansion of human umbilical cord blood-derived endothelial colony forming cells under serum-free conditions - a transcriptome analysis. Endothelial colony forming cells (ECFCs) were isolated from term umbilical cord blood units. ECFCs were expanded under standard, fetal bovine serum (FBS) containing endothelial medium, or transferred to chemically defined endothelial media without FBS. Microarray expression profiling was applied to compare the transcriptome profiles in FBS-containing versus FBS-free culture. Comparison of the expression patterns of ECFCs that were either cultured in FBS-containing medium or in serum-free medium (five replicates each).