Project description:Although it has been shown that HIF1 and 2 fulfill essential roles within the hematopoietic system and in the regulation of HSC fate, little is currently known about the specific mechanisms that are involved. We identified transcriptome changes induced by hypoxia, constitutively active HIF1(P402/564) and HIF2(P405/531) in human cord blood CD34+ cells. Thus, we were able to identify common hypoxia-HIF1-HIF2 gene signatures, but we also identified specific target genes that were exclusively regulated by HIF1, HIF2 or hypoxia. CB CD34+ cells were isolated by Miltenyi miniMACS column. Cells were prestimulated in HPGM with 100 ng/ml KITL, FLT3L and TPO for 3 days after which cells were placed either at normoxia or hypoxia (1% O2 for an additional 24 hrs). 5 independent CB CD34+ batches were used and isolated RNA was combined and used for Illumina beadhchip arrays HT12 v4
Project description:Although it has been shown that HIF1 and 2 fulfill essential roles within the hematopoietic system and in the regulation of HSC fate, little is currently known about the specific mechanisms that are involved. We identified transcriptome changes induced by hypoxia, constitutively active HIF1(P402/564) and HIF2(P405/531) in human cord blood CD34+ cells. Thus, we were able to identify common hypoxia-HIF1-HIF2 gene signatures, but we also identified specific target genes that were exclusively regulated by HIF1, HIF2 or hypoxia. CB CD34+ cells were isolated by Miltenyi miniMACS column. Cells were prestimulated in HPGM with 100 ng/ml KITL, FLT3L and TPO for 48 hrs. Cells were transduced with control pRRL-IRS2-EGFP lentiviral vectors or vectors expressing HIF1α(P402A,P564A) or HIF2α(P405A,P531A) in one or two rounds of 12 hrs each. 24 hrs later transduced cells were sorted after which RNA was isolated. 5 independent CB CD34+ batches were isolated, transduced and sorted, and isolated RNA was combined and used for Illumina beadhchip arrays HT12 v4
Project description:CB CD34+ cells were were transduced with control (tNGFR) or CITED2 overexpression lentivectors, or control (shSCR) or shRNA CITED2 lentivectors and mRNA was isolated in order to investigate global gene expression changes upon perturbation of CITED2. CB CD34+ cells were isolated by Miltenyi miniMACS column. Cells were prestimulated in HPGM with 100 ng/ml KITL, FLT3L and TPO for 12 hrs. Cells were transduced with control (tNGFR) or CITED2 overexpression lentivectors, or control (shSCR) shRNA CITED2 lentivectors, in three rounds over 48 hrs. Transduced cells were sorted after which RNA was isolated for Illumina beadhchip arrays HT12 v4.
Project description:CB CD34+ cells were isolated by Miltenyi miniMACS column. Cells were prestimulated in HPGM with 100 ng/ml KITL, FLT#L and TPO for 48 hrs. Cells were transduced with control MiNR1 or STAT5A-ER in three rounds over 48 hrs. Hematopoietic stem cells (HSCs), common myeloid progenitors (CMPs), granulocyte/macrophage progenitors (GMPs), and megakaryocyte/erythroid progenitors (MEPs) were sorted (for details see Blood 2011, Fatrai et al). cells were stimulated with 100 ng/ml 4OHT for 24 hrs after which RNA was isolated for Illumina beadhchiop arrays HT12 v3 CB CD34+ cells were isolated by Miltenyi miniMACS column. Cells were prestimulated in HPGM with 100 ng/ml KITL, FLT#L and TPO for 48 hrs. Cells were transduced with control MiNR1 or STAT5A-ER in three rounds over 48 hrs. Hematopoietic stem cells (HSCs), common myeloid progenitors (CMPs), granulocyte/macrophage progenitors (GMPs), and megakaryocyte/erythroid progenitors (MEPs) were sorted (for details see Blood 2011, Fatrai et al). cells were stimulated with 100 ng/ml 4OHT for 24 hrs after which RNA was isolated for Illumina beadhchiop arrays HT12 v3
Project description:Transciptome analysis of CD34+ enriched human HSPC lentivirally transduced with cohesin WT or mutant CD34+ enriched HSPCs from cord blood were transduced with a constitutive lentiviral vector expressing cohesin WT or mutant tagged to GFP. After 72hrs cells were GFP+ sorted and subjected to downstream microarray protocol.
Project description:In order to identify cells expressing RUNX1c during hematopoietic differentiation of human embryonic stem cells (hESCs), we targeted GFP downstream of the RUNX1 distal promoter. GFP was observed from 10-25 days of embryoid body differentiation and accurately mirrored expression of the endogenous RUNX1c isoform. GFP was restricted to CD45+ hematopoietic cells and GFP+CD34+ cells were highly enriched for progenitor cells. Appearance of the first wave of hematopoietic blast colony forming cells (Bl-CFC) in d3-4 embryoid bodies, antedated the expression of RUNX1c. These results confirm a role for RUNX1c in marking a second wave of hematopoietic progenitor cells in differentiating hESCs. The purpose of the cord blood samples was to perform comparison of them to the gene expression profiles of the Runx fractions - as the cord blood represents a heterogeneous mix of hematopoietic stem cells and multipotent progenitors cells.
Project description:The prognosis of infant B-cell acute lymphoblastic leukemia (iB-ALL) remains dismal, especially in patients harboring the MLL-AF4 (KTM2A-AFF1) rearrangement, which arises prenatally in early hematopoietic stem/progenitor cells (HSPCs). MLL-AF4+ B-ALL shows a bimodal localization of the MLL gene breakpoint within the MLL break cluster region, and two subgroups of patients based on the gene expression pattern of the HOXA/MEIS cluster have been identified. The pathogenic mechanisms in MLL-AF4+ B-ALL are challenging to study functionally due to the absence of faithful human cellular models recapitulating the disease phenotype and latency. Here, we assess the molecular contribution and leukemogenic capacity of MLL breakpoints occurring in either intron 10 (MLLi10, centromeric) or intron 12 (MLLi12, telomeric) in ontogenically-different human HSPCs sourced prenatally (fetal liver) and neonatally (cord blood). CRISPR-Cas9-induced MLL-AF4 (MA) targeting either MLLi10 (Mi10A) or MLLi12 (Mi12A) causes MA-driven in vitro myeloid immortalization in both fetal liver- and cord blood-CD34+ HSPCs. The cellular ontogeny and the location of the MLL breakpoint influenced the capacity of MLL-edited CD34+ HSPCs to initiate pro-B-ALL in vivo, which faithfully recapitulated the molecular, transcriptomic and methylome profiles of patients with primary MA+ iB-ALL. This dataset contains the DNA methylation information (Illumina MethylationEPIC Beadchip platform) of MLL-edited CD34+ cells (i10 or i12). BCPs, used as controls, were obtained from E-MTAB-8505
Project description:Umbilical cord blood (CB) is a non-invasive, convenient and broadly used source of hematopoietic stem cells (HSCs) for allogeneic stem cell transplantation. However, limiting numbers of HSCs remain a major constraint for its clinical application. One feasible option would be to expand HSCs to improve therapeutic outcome, however available protocols and the molecular mechanisms governing the self-renewal of HSC are unclear. Here we show that ectopic expression of a single miRNA, miR-125a, in purified murine and human multipotent progenitors (MPP) resulted in increased self-renewal and robust long-term multi-lineage repopulation in transplanted recipient mice. Using quantitative proteomics and Western blot analysis, we identified a restricted set of miR-125a targets which revealed the involvement of the MAP kinase signaling pathway in conferring long-term repopulating capacity to multipotent progenitors in human and mice. Our findings offer the innovative potential to use MPP with enhanced self-renewal activity to augment limited sources of HSC to improve clinical protocols.
Project description:Natural killer (NK) cells represent one of three lymphoid lineages and play a vital role in controlling viral infections and cancer. In contrast to B and T lymphopoiesis where cellular and regulatory pathways have been extensively characterized, the cellular stages of early human NK-cell commitment remain poorly understood Here we described a novel NK-lineage restricted progenitor (NKP) in fetal development, umbilical cord blood and adult bone marrow. We used microarrays to detail the global programme of gene expression genes of this new progenitor. Global gene expression analysis was performed on the NKP, multipotent progenitors LMPP, common lymphoid progenitor candidate and mature NK cells purified from Cord blood CD34+ cells (3-4 replicates, 2 experiments)
Project description:Mononuclear cells were isolated from umbilical cord blood (UCB) using Lymphoprep sucrose-gradient centrifugation (1.077 g/ml, Nycomed Pharma, Oslo, Norway). Immunomagnetic cell separation, using magnetic beads coated with CD34 antibodies (Miltenyi Biotec, Gladbach, Germany), was performed to isolate CD34-positive hematopoietic progenitor cells (CB-CD34+ cells). To generate retrovirus, bicistronic retroviral DNA constructs were used expressing the ETV6-RUNX1 or AML1-ETO fusion gene and enhanced Green Fluorescent Protein (eGFP). As a control, a construct expressing only eGFP was used. Both vectors consisted of a pMSCV promoter region, an internal ribosomal entry site and an ampicillin resistance cassette. HEK293T cells were co-transfected with these constructs and second-generation retroviral packaging vectors using XtremeGENE 9 tranfection reagents (Roche, Basel, Switzerland). Viral particles were collected in IMDM 48 hours after transfection. CD34+ haematopoietic progenitors, pre-cultured overnight as described above, upon which cells were divided in two fractions. One fraction was transduced with ETV6-RUNX1-IRES-eGFP or AML1-ETO-IRES-eGFP, while the other fraction was transduced with control EV-IRES-eGFP. Transductions were performed with fresh retrovirus in retronectin (Takara, Otsu, Japan) coated wells. After sorting, DAPI- CD34+ GFP+ CB-CD34+ cells were lysed and RNA was extracted using Nucleospin RNA XS extraction columns according to manufacturer’s protocol (Macherey-Nagel, Düren, Germany). Quality of RNA was determined by on-chip-electrophoresis using a RNA Pico Chip according to manufacturer’s protocol (Agilent Technologies, Santa Clara, CA, USA). RNA Integrity scores (RIN) were higher than 8 for all samples. RNA was subsequently linearly amplified using the Nugen WT-Amplification™ pico system (Nugen, San Carlos, CA, USA). This system is based on RNA-dependent DNA polymerase activity and was previously reported to be most suitable for amplification and gene expression of picograms of input RNA.