This SuperSeries is composed of the SubSeries listed below.
GPI-80 defines self-renewal ability in hematopoietic stem cells during human development.
Specimen part
View SamplesAdvances in pluripotent stem cell and reprogramming technologies have given hope of generating hematopoietic stem cells (HSC) in culture. To succeed, greater understanding of the self-renewing HSC during human development is required. We discovered that glycophosphatidylinositol-anchored surface protein GPI-80 (Vanin 2) defines a distinct subpopulation of human fetal hematopoietic stem/progenitor cells (HSPC) with self-renewal ability. CD34+CD90+CD38-GPI-80+ HSPC were the sole population that maintained proliferative potential and undifferentiated state in bone marrow stroma co-culture, and engrafted in immunodeficient mice. GPI-80 expression also enabled tracking of HSC migration between human fetal hematopoietic niches. The most highly enriched surface protein in GPI-80+ HSPC as compared to their progeny was Integrin alpha-M (ITGAM), which in leukocytes cooperates with GPI-80 to support migration. Knockdown of either GPI-80 or ITGAM was sufficient to perturb undifferentiated HSPC in stroma co-culture. These findings indicate that human fetal HSC utilize common mechanisms with leukocytes for cell-cell interactions governing HSC self-renewal.
GPI-80 defines self-renewal ability in hematopoietic stem cells during human development.
Specimen part
View SamplesAdvances in pluripotent stem cell and reprogramming technologies have given hope of generating hematopoietic stem cells (HSC) in culture. To succeed, greater understanding of the self-renewing HSC during human development is required. We discovered that glycophosphatidylinositol-anchored surface protein GPI-80 (Vanin 2) defines a distinct subpopulation of human fetal hematopoietic stem/progenitor cells (HSPC) with self-renewal ability. CD34+CD90+CD38-GPI-80+ HSPC were the sole population that maintained proliferative potential and undifferentiated state in bone marrow stroma co-culture, and engrafted in immunodeficient mice. GPI-80 expression also enabled tracking of HSC migration between human fetal hematopoietic niches. The most highly enriched surface protein in GPI-80+ HSPC as compared to their progeny was Integrin alpha-M (ITGAM), which in leukocytes cooperates with GPI-80 to support migration. Knockdown of either GPI-80 or ITGAM was sufficient to perturb undifferentiated HSPC in stroma co-culture. These findings indicate that human fetal HSC utilize common mechanisms with leukocytes for cell-cell interactions governing HSC self-renewal.
GPI-80 defines self-renewal ability in hematopoietic stem cells during human development.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Medial HOXA genes demarcate haematopoietic stem cell fate during human development.
Specimen part
View SamplesThe derivation of functional, transplantable HSCs from an pluripotent stem cells in vitro holds great promise for clinical therapies, but is unachieved. In order to achieve full functionality of HSCs, it is vital to determine the extent to which PSCs can currently be differentiated to the HSC program in vitro and identify the remaining dysregulated genetic pathways.
Medial HOXA genes demarcate haematopoietic stem cell fate during human development.
Specimen part
View SamplesRA signalling regulated endothelial to hematopoietic transition and HSC generation. Overall design: EB- or FL-derived HSPC were profiled before (d0) or after (d6) 6 days of treatment with 0.2uM AM580 on OP9, and after 6 additional days of expandion of OP9 (d12) without treatment.
Medial HOXA genes demarcate haematopoietic stem cell fate during human development.
No sample metadata fields
View SamplesHOXA7 regulates FL-HSPC self-renewal in vitro and in vivo. We profiled EB-HSPCs after HOXA7 overexpression (EB-HOXA7), or with a control vector (EB-CTR), to assess the gene expression programs regulated by HOXA7. Overall design: CD34+CD38-CD43+CD90+ HSPCs were infected with lentiviral FUGW vector either empty (FUGW-GFP) or encoding HOXA7(FUGW-GFP-HOXA7) protein. Cells were expanded on op9 for 15 days and than sorted for GFP HSPC immunophenotype.
Medial HOXA genes demarcate haematopoietic stem cell fate during human development.
No sample metadata fields
View SamplesThe production of definitive haematopoietic stem/progenitor cells from human pluripotent stem cells (hPSCs) remains a significant challenge. Using reporter lines to track the endothelial (SOX17) to haematopoietic (RUNX1C) transition, we found that hPSC differentiated in growth factor supplemented serum free medium generated RUNX1C+CD34+ clonogenic cells that homed to the bone marrow, but did not engraft. Compared to repopulation-competent cord blood CD34+ cells, RUNX1C+CD34+ progenitors lacked HOXA gene expression, indicating incorrect mesoderm patterning. This deficiency was ameliorated by a timed pulse of WNT activation combined with ACTIVIN antagonism. Significantly, these HOXA+ cultures now formed complex SOX17+ vessels that produced fetal liver-like haematopoietic cells, similar to the human aorta-gonad-mesonephros (AGM). Comparison of transcriptional profiles of these nascent haematopoietic stem/progenitors with cells isolated from human AGM confirmed significant similarities, consistent with the assignment of our in vitro generated cells to the definitive human haematopoietic lineage. Our findings argue that HOXA codes established early in differentiation predict cellular potential and provide correct cell patterning for the specification of definitive haematopoietic lineages from hPSCs. Overall design: mRNA profiles of 26 samples were obtained for 5 different cell populations and 2 different treatments.
Differentiation of human embryonic stem cells to HOXA<sup>+</sup> hemogenic vasculature that resembles the aorta-gonad-mesonephros.
Treatment, Subject
View SamplesMonitoring genome-wide, cell-specific responses to human disease, although challenging, holds great promise for medicines future. Patients with injury severe enough to develop multiple organ dysfunction syndrome (MODS) are known to have multiple immune derangements, including T-cell apoptosis and anergy combined with depressed monocyte antigen presentation. Genome-wide expression analysis of highly-enriched circulating leukocyte subpopulations, combined with cell-specific pathway analyses, offers a previously unavailable opportunity to discover novel leukocyte regulatory networks in critically injured patients. Severe injury induced significant changes in the T-cell, monocyte, and total leukocyte transcriptome, with only 12% of these genomic changes common to all three cell populations. T-cell-specific pathway analyses identified increased gene expression of several novel inhibitory receptors (PD-1, CD152, NRP-1, Lag3), and concomitant decreases in stimulatory receptors (CD28, CD4, IL-2Ralpha). Functional analysis of T-cells and monocytes confirmed reduced T-cell proliferation and increased cell surface expression of negative signaling receptors paired with decreased monocyte costimulation ligands. Thus, genome-wide expression from highly-enriched cell populations combined with knowledge-based pathway analyses leads to the identification of novel regulatory networks differentially expressed in injured patients. Importantly, application of cell separation, genome-wide expression, and cell specific pathway analyses can be used to discover novel pathway alterations in human disease.
Cell-specific expression and pathway analyses reveal alterations in trauma-related human T cell and monocyte pathways.
No sample metadata fields
View SamplesOligonucleotide and complementary DNA microarrays are being used to subclassify histologically similar tumours, monitor disease progress, and individualize treatment regimens. However, extracting new biological insight from high-throughput genomic studies of human diseases is a challenge, limited by difficulties in recognizing and evaluating relevant biological processes from huge quantities of experimental data. Here we present a structured network knowledge-base approach to analyse genome-wide transcriptional responses in the context of known functional interrelationships among proteins, small molecules and phenotypes. This approach was used to analyse changes in blood leukocyte gene expression patterns in human subjects receiving an inflammatory stimulus (bacterial endotoxin). We explore the known genome-wide interaction network to identify significant functional modules perturbed in response to this stimulus. Our analysis reveals that the human blood leukocyte response to acute systemic inflammation includes the transient dysregulation of leukocyte bioenergetics and modulation of translational machinery. These findings provide insight into the regulation of global leukocyte activities as they relate to innate immune system tolerance and increased susceptibility to infection in humans.
A network-based analysis of systemic inflammation in humans.
No sample metadata fields
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