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GSE33031
Mus musculus
6 Downloadable Samples
Affymetrix Mouse Genome 430 2.0 Array (mouse4302)
Description
To guarantee blood supply throughout adult life hematopoietic stem cells (HSCs) need to carefully balance between self-renewing cell divisions and quiescence. Identification of genes controlling HSC self-renewal is of utmost importance given that HSCs are the only stem cells with broad clinical applications. Transcription factor PU.1 is one of the major regulators of myeloid and lymphoid development. Recent reports suggest that PU.1 mediates its functions via gradual expression level changes rather than binary on/off states. So far, this has not been considered in any study of HSCs and thus, PU.1s role in HSC function has remained largely unclear. Here we demonstrate using hypomorphic mice with an engineered disruption of an autoregulatory feedback loop that decreased PU.1 levels resulted in loss of key HSC functions, all of which could be fully rescued by restoration of proper PU.1 levels via a human PU.1 transgene. Mechanistically, we found excessive HSC cell divisions and altered expression of cell cycle regulators whose promoter regions were bound by PU.1 in normal HSCs. Adequate PU.1 levels were maintained by a mechanism of direct autoregulation restricted to HSCs through a physical interaction of a -14kb enhancer with the proximal promoter. Our findings identify PU.1 as novel regulator controling the switch between cell division and quiescence in order to prevent exhaustion of HSCs. Given that even moderate level changes greatly impact stem cell function, our data suggest important therapeutic implications for leukemic patients with reduced PU.1 levels. Moreover, we provide first proof, that autoregulation of a transcription factor, PU.1, has a crucial function in vivo. We anticipate that our concept of how autoregulation forms an active chromosomal conformation will impact future research on transcription factor networks regulating stem cell fate.
Publication Title
Sustained PU.1 levels balance cell-cycle regulators to prevent exhaustion of adult hematopoietic stem cells.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 20 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Transplantation with low numbers of hematopoietic stem cells (HSCs), found in many of the publically accessible cryopreserved umbilical cord blood (UCB) units, leads to delayed time to engraftment, high graft failure rates, and early mortality in many patients. A chemical screen in zebrafish identified the prostaglandin compound, 16,16 dimethyl prostaglandin E2 (dmPGE2), to be a critical regulator of hematopoietic stem cell homeostasis. We hypothesized that an ex vivo modulation with dmPGE2 prior to transplantation would lead to enhanced engraftment by increasing the effective dose of hematopoietic stem cells (HSCs) in cord blood. A phase I trial of reduced-intensity double UCB transplantation was performed to evaluate safety, rates of engraftment and fractional chimerism of dmPGE2 enhanced UCB units. To explore potential causes of the lack of enhanced efficacy in the first cohort, we characterized HSCs to determine whether the prostaglandin pathway was being activated under the ex vivo incubation conditions (4C, 10M dmPGE2, 60 minutes). Incubation conditions were identified (37C, 10M dmPGE2, 120 minutes) that maximize the activation of the prostaglandin pathway by dmPGE2 in human CD34+ cells.
Publication Title
Prostaglandin-modulated umbilical cord blood hematopoietic stem cell transplantation.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the effective dose of HSCs.
Publication Title
Prostaglandin-modulated umbilical cord blood hematopoietic stem cell transplantation.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 9 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the "effective dose" of HSCs.
Publication Title
Prostaglandin-modulated umbilical cord blood hematopoietic stem cell transplantation.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 6 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the effective dose of HSCs.
Publication Title
Prostaglandin-modulated umbilical cord blood hematopoietic stem cell transplantation.
Sample Metadata Fields
Specimen part, Treatment
View Samples- Homo sapiens
- 4 Downloadable Samples
- Affymetrix Human Genome U133 Plus 2.0 Array (hgu133plus2)
Description
Umbilical cord blood (UCB) is a valuable source of hematopoietic stem cells (HSCs) for use in allogeneic transplantation. Key advantages of UCB are rapid availability and less stringent requirements for HLA matching. However, UCB contains an inherently limited HSC count, which is associated with delayed time to engraftment, high graft failure rates and early mortality. 16,16 dimethyl prostaglandin E2 (dmPGE2) was previously identified to be a critical regulator of HSC homeostasis and we hypothesized that a brief ex vivo modulation could improve patient outcomes by increasing the effective dose of HSCs.
Publication Title
Prostaglandin-modulated umbilical cord blood hematopoietic stem cell transplantation.
Sample Metadata Fields
Specimen part
View Samples- Homo sapiens
- 24 Downloadable Samples
- Affymetrix HT Human Genome U133A Array (hthgu133a)
Description
We used an in vivo short hairpin RNA (shRNA) screening approach to identify genes that are essential for MLL-AF9 acute myeloid leukemia (AML). We found that Integrin Beta 3 (Itgb3) is essential for murine leukemia cells in vivo, and for human leukemia cells in xenotransplantation studies. In leukemia cells, Itgb3 knockdown impaired homing, downregulated LSC transcriptional programs, and induced differentiation via the intracellular kinase, Syk. In contrast, loss of Itgb3 in normal HSPCs did not affect engraftment, reconstitution, or differentiation. Finally, we confirmed that Itgb3 is dispensable for normal hematopoiesis and required for leukemogenesis using an Itgb3 knockout mouse model. Our results establish the significance of the Itgb3 signaling pathway as a potential therapeutic target in AML.
Publication Title
In Vivo RNAi screening identifies a leukemia-specific dependence on integrin beta 3 signaling.
Sample Metadata Fields
Cell line, Treatment, Time
View Samples- Drosophila melanogaster
- 4 Downloadable Samples
Illumina HiSeq 2500
Description
We have investigated the effect of RRP6 depletion on the transcriptome of S2 cells using Illumina deep RNA sequencing. We have also carried out Illumina ChIP-seq analysis of RRP6 genome occupancy in control S2 cells (GFP-KD) and in cells depleted of SU(VAR)3-9. Overall design: 8 samples total; 4 RNA-Seq samples (1 RRP6-KD and 1 GFP-KD, 2 biological replicates each); and 4 ChIP-Seq samples (RRP6 IP in GFP-KD and in Su(var)3-9-KD conditions; plus their respective Input samples).
Publication Title
An Interaction between RRP6 and SU(VAR)3-9 Targets RRP6 to Heterochromatin and Contributes to Heterochromatin Maintenance in Drosophila melanogaster.
Sample Metadata Fields
Subject
View Samples- Rattus norvegicus
- 6 Downloadable Samples
- Affymetrix Rat Expression 230A Array (rae230a)
Description
Mechanical forces are essential for normal fetal lung development. However, the cellular and molecular mechanisms regulating this process remain largely unknown. In the present study, we used oligonucleotide microarray technology to investigate gene expression profile in cultured E19 rat fetal lung type II epithelial cells exposed to a level of mechanical strain similar to that observed in utero. Significance Analysis of Microarrays (SAM) identified 92 genes differentially expressed by strain. Interestingly, several members of the solute carrier family of amino acid transporters, genes involved in amino acid synthesis and development, and amiloride-sensitive epithelial sodium channel gene were induced by strain. These results were confirmed by quantitative real-time polymerase chain reaction (qRT-PCR). Thus, this study identifies genes induced by strain that may be important for amino acid signaling pathways, protein synthesis and development in fetal type II cells. In addition, these data suggest that mechanical forces may contribute to facilitate lung fluid reabsorption in preparation for birth. Taken together, the present investigation provides further insights into how mechanical forces may modulate fetal lung development.
Publication Title
DNA microarray reveals novel genes induced by mechanical forces in fetal lung type II epithelial cells.
Sample Metadata Fields
Sex, Specimen part
View Samples- Mus musculus
- 6 Downloadable Samples
- Affymetrix Mouse Gene 2.0 ST Array (mogene20st)
Description
Comparative analysis of FACS-sorted CCR2- and CCR2+ HSC in the steady state. CCR2+ HSC have fourfold higher proliferative rates than CCR2- HSC, are are biased towards the myeloid lineage and dominate the migratory HSC population.
Publication Title
Myocardial Infarction Activates CCR2(+) Hematopoietic Stem and Progenitor Cells.
Sample Metadata Fields
Specimen part
View Samples