Human hematopoietic leukemic k562 cells: control Vs CXCR4 constitutively active mutant cells
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
SUBMITTER: Gurudutta Gangenahalli
PROVIDER: E-GEOD-76544 | biostudies-arrayexpress |
REPOSITORIES: biostudies-arrayexpress
Similar Datasets
Project description:The low homing and engraftment efficiency especially in context of low availability of donor CD34+ HSPCs is a major challenge, which limits the clinical applications of HSC therapies. SDF-1/CXCR4 axis plays a principle role in the homing and engraftment of hematopoietic stem/progenitor cells. Activation of CXCR4 induces cell trafficking and homing to the marrow microenvironment, where it retains hematopoietic stem cells in close contact with marrow stromal cells. The aim of our study is to understand the mechanisms of other molecules acting along with CXCR4 to provide new insights in the regulation of cell phenotypes. This data shows the transcriptional profiling of human hematopoetic leukemic k562 cells comparing control, wild type and two different mutant cells where mutant cells have constitutively activated CXCR4 gene expression where mutant 1 and 2 have different aminoacid substituions.
2016-02-29 | GSE76544 | GEO
Project description:<p>We are studying the natural history, pathogenesis and treatment of patients with WHIM syndrome, an immunodeficiency disorder characterized by warts, hypogammaglobulinemia, recurrent infections and neutropenia usually due to autosomal dominant gain-of-function mutations in chemokine receptor <i>CXCR4</i>. We have identified a patient born with WHIM syndrome and the WHIM mutation <i>CXCR4<sup>R334X</sup></i> who has been disease-free for 20 years and who lacks <i>CXCR4<sup>R334X</sup></i> in myeloid cells, the cells that drive disease manifestations. She is a genetic and hematopoietic mosaic, since she still has the mutation in lymphoid cells and non-hematopoietic cells. Cytogenetics and microarray analysis revealed that the mechanism of loss of the mutation was deletion of the mutant allele from one copy of chromosome 2. Whole genome sequencing of patient neutrophil and skin fibroblast genomic DNA revealed that the mechanism of deletion was chromothripsis, a process of chromosome shattering resulting in deletions and rearrangements of the non-deleted chromosomal segments. In the patient, this process evidently occurred in a single hematopoietic stem cell (HSC), resulting in deletion of the disease allele <i>CXCR4<sup>R334X</sup></i> and one copy of 163 other genes on chromosome 2. This HSC evidently acquired a growth advantage and repopulated the HSC population and the myeloid lineage. Consistent with this, studies using gene targeted mice in competitive bone marrow transplantation experiments revealed that selective <i>Cxcr4</i> haploinsufficiency (inactivation of one copy of <i>Cxcr4</i> and not of any other genes) was sufficient to confer a strong engraftment advantage over bone marrow cells from wild type mice as well as bone marrow cells from a mouse model of WHIM syndrome. These results suggest that <i>CXCR4</i> knockdown may be a useful strategy to enhance bone marrow engraftment in the absence of toxic bone marrow conditioning regimens.</p>
| phs000856 | dbGaP
Project description:Homing and engraftment of hematopoietic stem cells (HSCs) to the bone marrow (BM) involve a complex interplay between chemokines, cytokines, and non-peptide molecules. Extracellular nucleotides and their cognate P2 receptors are emerging as key-factors of inflammation and related chemotactic responses. In this study, we investigated the activity of extracellular adenosine-triphosphate (ATP) and uridine-triphosphate (UTP) on CXCL12-stimulated CD34+ HSC chemotaxis. In vitro, UTP significantly improved HSC migration, inhibited cell membrane CXCR4 down-regulation of migrating CD34+ cells and increased cell adhesion to fibronectin. In vivo, pre-incubation with UTP significantly enhanced the BM homing efficiency of human CD34+ cells in immunodeficient mice. Pertussis toxin blocked CXCL12- and UTP-dependent chemotactic responses, suggesting that G-protein alpha-subunits (Gαi) may provide a converging signal for CXCR4- and P2Y-activated transduction pathways. In addition, gene expression profiling of UTP-treated CD34+ cells and in vitro inhibition assays demonstrated that Rho guanosine 5â-triphosphatases (GTPase) Rac2 and downstream effectors Rho GTPaseâactivated kinases 1 and 2 (ROCK1/2) are involved in UTP-promoted/CXCL12-dependent HSC migration. Our data suggest that UTP may physiologically modulate the migration of HSCs and their homing to the BM, in concert with CXCL12, via the activation of converging signaling pathways between CXCR4 and P2Y receptors, involving Gαi proteins and RhoGTPases. Experiment Overall Design: Highly purified CD34+ cells from 6 healthy donors were seeded at 1000000 cells/ml in serum free medium (EX vivo 15) w/o cytokines and treated with 10 mM UTP, 150ng/ml CXCL12, or 10 mM UTP plus 150ng/ml CXCL12 respectively for 24 hours. As a control, CD34+ untreated cells were maintained in the same culture conditions at the same time.
2008-06-13 | E-GEOD-5168 | biostudies-arrayexpress
Project description:Homing and engraftment of hematopoietic stem cells (HSCs) to the bone marrow (BM) involve a complex interplay between chemokines, cytokines, and non-peptide molecules. Extracellular nucleotides and their cognate P2 receptors are emerging as key-factors of inflammation and related chemotactic responses. In this study, we investigated the activity of extracellular adenosine-triphosphate (ATP) and uridine-triphosphate (UTP) on CXCL12-stimulated CD34+ HSC chemotaxis. In vitro, UTP significantly improved HSC migration, inhibited cell membrane CXCR4 down-regulation of migrating CD34+ cells and increased cell adhesion to fibronectin. In vivo, pre-incubation with UTP significantly enhanced the BM homing efficiency of human CD34+ cells in immunodeficient mice. Pertussis toxin blocked CXCL12- and UTP-dependent chemotactic responses, suggesting that G-protein alpha-subunits (Gαi) may provide a converging signal for CXCR4- and P2Y-activated transduction pathways. In addition, gene expression profiling of UTP-treated CD34+ cells and in vitro inhibition assays demonstrated that Rho guanosine 5’-triphosphatases (GTPase) Rac2 and downstream effectors Rho GTPase–activated kinases 1 and 2 (ROCK1/2) are involved in UTP-promoted/CXCL12-dependent HSC migration. Our data suggest that UTP may physiologically modulate the migration of HSCs and their homing to the BM, in concert with CXCL12, via the activation of converging signaling pathways between CXCR4 and P2Y receptors, involving Gαi proteins and RhoGTPases. Keywords: treatment comparison
2006-10-04 | GSE5168 | GEO
Project description:Efficient bone marrow homing is a prerequisite for successful engraftment of transplanted HSPC. This study aims at determining factors important in homing of these cells from the blood to the marrow and their re-engraftment. We have isolated nucleated cells from mobilized peripheral blood stem cell harvests (PBSC). CD34+ hematopoietic stem and progenitor cells (HSPC) were enriched from PBSC harvests by immunomagnetic separation using negative selection method. Enriched cells were cultured in vitro for expansion in presence or absence of cytokine (GF: SCF+TPO+FLT3L) and/or chemokine (homing factor SDF1) mixture for 8 days at 370C in humidified atmosphere of 5% CO2 in air. GF+SDF1 –stimulated HSPC showed significantly increased total nucleated ells as well as CD34+ cells as compared to GF-stimulated HSPC as well s unstimulated cultured HSPC. On transplantation of these cells in vivo in mice model who were previously irradiated at sublethal dose of 375cGy, it was observed that GF+SDF1-stimulated HSPC exhibited significantly better engraftment in terms of presence of human CD45+ cells in mouse blood at 6 week post –transplantation. We have compared gene expression profiles of mobilized PBSC harvest cells, enriched CD34+ HSPC population and HSPC cultured in plain media, in presence with GF and in presence of GF+SDF1 derived from mobilized PBSC harvests with respect to genes involved in homing and engraftment capacities.
2016-12-11 | GSE37334 | GEO
Project description:Human hematopoietic leukemic k562 cells: control Vs CXCR4 constitutively active mutant cells
| PRJNA307693 | ENA
Project description:Human pluripotent stem cells (hPSC) generate hematopoietic progenitor cells (HPC), but fail to engraft xenograft models, which is a hallmark feature of adult/somatic hematopoietic stem cells (HSC) from human donors. Progress to derive hPSC-derived HSCs has relied on cell autonomous approaches that force expression of transcription factors (TF), however the role of bone marrow (BM) niche remains poorly understood. Here, we quantified a failure of hPSC-HPCs to survive even in the first 24 h upon transplantation into the BM. Across several hPSC-HPC differentiation methodologies, we identified the lack of CXCR4 expression and network function. Ectopic CXCR4 conferred CXCL12-dependent signaling of hPSC-HPCs in biochemical assays and increased migration/chemotaxis and progenitor capacity, as well as survival and proliferation following transplantation in vivo. In addition, hPSC-HPCs forced to express CXCR4 demonstrated a transcriptional shift toward somatic HPCs, but this approach failed to produce long-term HSC engraftment. Our results reveal that independent of differentiation methods, networks involving CXCR4 should be targeted to generate HSCs with in vivo function from hPSCs.
2018-06-21 | GSE106721 | GEO
Project description:The identification of small molecules which either increase the number and/or enhance the activity of CD34+ hematopoietic stem and progenitor cells (HSPCs) during ex-vivo expansion has remained challenging. Applying an unbiased in vivo chemical screen in a transgenic (c-myb:EGFP) zebrafish embryo model, histone deacetylase inhibitors (HDACI) (valproic acid, resminostat and entinostat) were shown to significantly amplify the number of phenotypic hematopoietic precursors. The identified HDACIs were confirmed to significantly enhance also the expansion of human HSPCs during ex vivo treatment. Long-term functionality of ex vivo expanded human HSPCs was verified in a xenotransplantation model using NSG mice. However, the HDACI induced proliferation of HSPCs was associated with short-term functional changes. One of the identified hits, valproic acid (VPA), increased the adhesion capacity of CD34+ cells on primary mesenchymal stromal cells and reduced their chemokine-mediated migration capacity in vitro. In line with the reduced migratory potential in vitro, homing as well as early engraftment of VPA treated human CD34+ cells was significantly impaired in the xenotransplantation model. Our data confirms that HDACI treatment leads to a net expansion of HSPCs cells with long-term engraftment potential across different species. However impaired homing and short-term-engraftment has to be kept in mind when designing clinical transplantation protocols. In addition, our gene expression analysis (RNA-Seq) revealed expression of several genes that were altered in CD34+ cells by VPA treatment including cell adhesion molecules and Notch and wnt genes which has been shown to be involved in preservation of stem cell properties.
2017-11-01 | GSE90552 | GEO
Project description:Acute myeloid leukemia (AML) is defined by an accumulation of immature myeloid blasts in the bone marrow. To identify key dependencies of AML stem cells in vivo, here we use a CRISPR-Cas9 screen targeting cell surface genes in a syngeneic MLL-AF9 AML mouse model and show that CXCR4 is a top cell surface regulator of AML cell growth and survival. Deletion of Cxcr4 in AML cells eradicates leukemia cells in vivo without impairing their homing to the bone marrow. In contrast, the CXCR4- ligand CXCL12 is dispensable for leukemia development in recipient mice. Moreover, expression of mutated Cxcr4 variants reveals that CXCR4 signaling is essential for leukemia cells. Notably, loss of CXCR4 signaling in leukemia cells leads to oxidative stress and differentiation in vivo. Taken together, our results identify CXCR4 signaling as essential for AML stem cells by protecting them from differentiation independent of CXCL12 stimulation.
2019-11-15 | GSE135275 | GEO
Project description:Examining the effects of PRMT5 loss on the gene expression profile of hematopoietic stem and progenitor cells We established the PRMT5 conditional KO mice, and bred the mice with Mx1 cre transgenic mice to delete PRMT5 in hematopoietic cells. We isolated hematopoetic stem and progenitor cells 3 days after PRMT5 deletion, and examined the gene expression files using RNA-sequencing.
2015-07-15 | E-GEOD-69937 | biostudies-arrayexpress