Project description:The transcriptome of shRenilla and shGPRC5C in long term hematopoietic stem cells (LT-HSC) from human bone marrow was assessed by RNAseq.
Project description:The transcriptome of LT-HSC (CD34+CD38-CD45RA+CD90+CD49f+) and ST-HSC (CD34+CD38-CD45RA+CD90-CD49f-) from healthy adult human Bone Marrow Cells were assessed by RNA-seq.
Project description:Study of the effects of at-RA treatment on the transcriptome of murine Long-Term Hematopoietic Stem Cells (LT-HSCs) in the context of myocardial infarction (MI). MI was induced in female C57BL/6J mice aged 6 to approximately 12 weeks through permanent occlusion of the left anterior descending artery (LAD). Mice were intraperitoneally injected on the 1st and 2nd day after MI surgery with either 30 mg/kg body weight at-RA (Sigma-Aldrich; MI+at-RA condition), or with the corresponding amount of DMSO in phosphate-buffered saline (PBS) (MI+vehicle condition). Two days after MI, LT-HSCs (Lin-negative, Sca1-positive, c-Kit-positive, CD150-positive, CD48-negative, CD34-negative) were isolated from the bone marrow, sorted, and analyzed for their transcriptome profiles. This study aimed to understand how at-RA treatment influences gene expression in LT-HSCs following MI.
Project description:Tumors contain a fraction of cancer stem cells that maintain the propagation of the disease. The CD34CD38_ cells, isolated from acute myeloid leukemia (AML), were shown to be enriched leukemic stem cells (LSC). We isolated the CD34CD38_ cell fraction from AML and compared their gene expression profiles to the CD34CD38 cell fraction, using microarrays. We found 409 genes that were at least twofold over- or underexpressed between the two cell populations. These include underexpression of DNA repair, signal transduction and cell cycle genes, consistent with the relative quiescence of stem cells, and chromosomal aberrations and mutations of leukemic cells. Comparison of the LSC expression data to that of normal hematopoietic stem cells (HSC) revealed that 34% of the modulated genes are shared by both LSC and HSC, supporting the suggestion that the LSC originated within the HSC progenitors. We focused on the Notch pathway since Jagged-2, a Notch ligand was found to be overexpressed in the LSC samples. We show that DAPT, an inhibitor of gamma-secretase, a protease that is involved in Jagged and Notch signaling, inhibits LSC growth in colony formation assays. Identification of additional genes that regulate LSC self-renewal may provide new targets for therapy. Microarrays were used to compare the gene expression patterns between AML CD34+CD38- cells and AML CD34+CD38+
Project description:It is widely accepted that hematopoietic progenitor cells (HPC) are tightly associated with discrete niches within the bone marrow. This molecular environment supports and regulates their self renewal and differentiation. AFT024 is a cell line derived from murine fetal liver that has been demonstrated to maintain human hematopoietic progenitors in an undifferentiated state in vitro. While various functional and genomic studies of this and other stromal layers have already been reported, the influence of the cellular microenvironment on the gene expression of HPC has not yet been systematically analyzed.<br> <br> The CD34+/CD38- fraction of human umbilical cord blood was parted and either cultivated on AFT024 [kindly provided by I. Lemischka] or without stromal feeder layer for 16h, 20h, 48h or 72h. Both fractions were then harvested and separated by vigorous pipetting and FACS sorted again to separate the HPC from AFT024. Global gene expression profiles were determined using a novel Human Genome cDNA Microarray of over 51,145 ESTs of the UnigenSet-RZPD3. In analogy, we have compared the gene expression profiles of CD34+/CD38- cells versus AFT024 to exclude that differential gene expression resulted from contaminating feeder layer cells.
Project description:The t(8;21) Acute Myeloid Leukaemia (AML) Kasumi-1cell line with N822K KIT mutation, is a model system for leukemogenesis. As AML initiating cells reside in the CD34+CD38- fraction, we addressed the refined cytogenomic characterization and miRNA expression of Kasumi-1 cell line and its FACS-sorted subpopulations focussing on this compartment. By conventional cytogenetics, Spectral Karyotyping and array-CGH the cytogenomic profile of Kasumi-1 cells evidenced only subtle regions differentially represented in CD34+CD38- cells. Expression profiling by a miRNA platform showed a set of miRNA differentially expressed in paired subpopulations and the signature of miR-584 and miR-182 upregulation in the CD34+CD38- fraction.
Project description:Epigenetic regulation plays an important role in cellular development and differentiation. A detailed map of the DNA methylation dynamics that occur during cell differentiation would contribute to decipher the molecular networks governing cell fate commitment. We used the most recent Illumina MethylationEPIC Beadchip platform to describe the genome-wide DNA methylation changes observed throughout hematopoietic maturation by analyzing multiple hematopoietic cell types at different developmental stages. We identified a plethora of DNA methylation changes that occur during human hematopoietic differentiation. Interestingly, we observed that T lymphocytes display a substantial enhancement of de novo CpG hypermethylation as compared to other hematopoietic cell populations.