Project description:(Single Cell Sequencing Data) Here we present an integrative, bottom-up approach towards emulating the human bone marrow in vitro. Our method harnesses the regenerative capacity of adult stem cells to self-assemble a complex, specialized microenvironment of human hematopoietic stem cells (HSCs) in a vascularized three-dimensional microphysiological system. Through flow cytometry and single-cell transcriptomic interrogation, we show that the microengineered niche can reconstitute HSC self-renewal, multilineage hematopoiesis, and complex ligand-receptor signaling pathways of the native human marrow. The ability of our model to generate functionally mature myeloid cells also makes it possible to mimic the key physiological processes of innate immunity including neutrophil chemotaxis and intravascular mobilization. To demonstrate the advanced application of the bone marrow-on-a-chip, we present i) a specialized model of bone marrow ablation by proton beam radiotherapy and ii) a multiorgan model of innate immune response against bacterial lung infection. This work advances our ability to reconstruct, probe, and deconvolve the complexity of the bone marrow niche, and may enable new capabilities to model human hematopoiesis and immunity for biomedical and pharmaceutical applications.
Project description:(Radiation Experiments: bulk sequencing data) Here we present an integrative, bottom-up approach towards emulating the human bone marrow in vitro. Our method harnesses the regenerative capacity of adult stem cells to self-assemble a complex, specialized microenvironment of human hematopoietic stem cells (HSCs) in a vascularized three-dimensional microphysiological system. Through flow cytometry and single-cell transcriptomic interrogation, we show that the microengineered niche can reconstitute HSC self-renewal, multilineage hematopoiesis, and complex ligand-receptor signaling pathways of the native human marrow. The ability of our model to generate functionally mature myeloid cells also makes it possible to mimic the key physiological processes of innate immunity including neutrophil chemotaxis and intravascular mobilization. To demonstrate the advanced application of the bone marrow-on-a-chip, we present i) a specialized model of bone marrow ablation by proton beam radiotherapy and ii) a multiorgan model of innate immune response against bacterial lung infection. This work advances our ability to reconstruct, probe, and deconvolve the complexity of the bone marrow niche, and may enable new capabilities to model human hematopoiesis and immunity for biomedical and pharmaceutical applications.
Project description:The importance of extrinsic regulation of hematopoietic stem cell activity is increasingly acknowledged. Here we report the generation of a new niche system, which supports expansion of mouse hematopoietic stem cells in vitro. Characterization of this niche revealed a transcriptional regulatory network including four critical factors, namely FOS, SPI1, KLF10 and TFEC. Interestingly, these factors are essential for osteoclastogenesis, thus revealing an osteoclastic network that supports hematopoietic stem cell self-renewal. Lentiviral vectors containing putative transcription factors regulating HSC expansion were transfected into GPE cells and gene expression values were compared to empty vector controls.
Project description:The importance of extrinsic regulation of hematopoietic stem cell activity is increasingly acknowledged. Here we report the generation of a new niche system, which supports expansion of mouse hematopoietic stem cells in vitro. Characterization of this niche revealed a transcriptional regulatory network including four critical factors, namely FOS, SPI1, KLF10 and TFEC. Interestingly, these factors are essential for osteoclastogenesis, thus revealing an osteoclastic network that supports hematopoietic stem cell self-renewal.
Project description:Hematopoietic stem cells (HSCs) inhabit distinct microenvironments within the adult bone marrow (BM) that govern the delicate balance between HSC quiescence, self-renewal, and differentiation. It has been suggested that quiescent HSCs localize adjacent to BM arteriole endothelial cells in a significant and non-random distribution. This data suggests that the arteriole BM vascular niche may be the primary HSC niche. Because the BM arteriole niche is composed of tightly-associated pericytes, including smooth muscle actin+, LepR+, Nestin+, NG2+, and nonmyelinating Schwann cells, we sought to begin to uncouple the arteriole BM EC niche by examining its capacity to support the maintenance and expansion of HSCs ex vivo and in vivo. We developed a method to isolate and culture BM arteriole endothelial cells in serum-/growth factor-free conditions, allowing for a non-biased approach to examining their instructive function. Utilizing our protocol, we demonstrate that BM endothelial cells, but not BM stromal cells, have the capacity to expand long-term repopulating, multi-lineage HSCs in lieu of complex serum and cytokine supplementation. In addition, transplantation of arteriole endothelial cells promoted rapid hematopoietic recovery and protected HSCs following an LD50 dose of myeloablative irradiation. These data demonstrate that arteriole-derived BM endothelial cells are endowed with the necessary signals to support the self-renewal and regenerative capacity of LT-HSCs and that transplantation of arteriole BM endothelial cells could be used as a therapeutic means to decrease pancytopenias associated with myeloablative treatments to treat a wide array of disease states. Transcriptome sequencing of bone marrow endothelial cells and bone marrow stroma, in vitro and in vivo, with and without HSC co-culture.
Project description:Specialized niche environments specify and maintain stem and progenitor cells, but little is known about the identities and functional interactions of niche components in vivo. Here, we describe a modular system for the generation of artificial hematopoietic niches in the mouse embryo. A circumscribed tissue that lacks niche function but is physiologically accessible for hematopoietic progenitor cells is functionalized by individual and combinatorial expression of four factors, the chemokines Ccl25 and Cxcl12, the cytokine Scf and the Notch ligand DLL4. The distinct phenotypes and variable numbers of hematopoietic cells in the resulting niches reveal synergistic, context-dependent and hierarchical interactions among niche effector molecules. The surprisingly simple rules determining niche outcomes enable the in vivo engineering of artificial niches conducive to the presence of distinct myeloid or T or B lymphoid lineage precursors. The dataset comprises 24 samples divided into eight sample groups each representing a different lymphoid progenitor cell type isolated from wild-type (+/-) or transgenic (-/-) thymic niches. -/-, Foxn1-deficient genotype; +/-, Foxn1 heterozygous phenotype; DP, CD4/CD8 double-poisztive thymocytes; DN3, CD4/CD8-negative stage 3 thymocytes; SP4, CD4 single-positive thymocytes; SP8, CD8 single-positive thymocytes; B IgM-, IgM surface negative B cells; B IgM+, IgM surface positive B cells; B IgM- -/-, IgM surface negative B cells from Foxn1-deficient genotype.
Project description:scRNA-seq was used to characterise hiPSC-derived kidney organoids differentiated within fully synthetic self-assembling peptide hydrogels of variable mechanical strengths and compare these to organoids differentiated within the animal-derived matrix, Matrigel. Organoids were matured in the respective matrices until day 24 of differentiation and 6 organoids per support matrix were then pooled and dissociated using the cold-active protease from Bacillus licheniformis. Cells were processed on the 10x Genomics Chromium platform using the Single-Cell 3’ v3.1 protocol. The NextSeq500 (Illumina) was used to sequence the libraries generated and initial processing of the data was carried out using the 10X Genomic Cell Ranger v3.1.0 pipeline.
Project description:Hematopoietic stem cells (HSCs) inhabit distinct microenvironments within the adult bone marrow (BM) that govern the delicate balance between HSC quiescence, self-renewal, and differentiation. It has been suggested that quiescent HSCs localize adjacent to BM arteriole endothelial cells in a significant and non-random distribution. This data suggests that the arteriole BM vascular niche may be the primary HSC niche. Because the BM arteriole niche is composed of tightly-associated pericytes, including smooth muscle actin+, LepR+, Nestin+, NG2+, and nonmyelinating Schwann cells, we sought to begin to uncouple the arteriole BM EC niche by examining its capacity to support the maintenance and expansion of HSCs ex vivo and in vivo. We developed a method to isolate and culture BM arteriole endothelial cells in serum-/growth factor-free conditions, allowing for a non-biased approach to examining their instructive function. Utilizing our protocol, we demonstrate that BM endothelial cells, but not BM stromal cells, have the capacity to expand long-term repopulating, multi-lineage HSCs in lieu of complex serum and cytokine supplementation. In addition, transplantation of arteriole endothelial cells promoted rapid hematopoietic recovery and protected HSCs following an LD50 dose of myeloablative irradiation. These data demonstrate that arteriole-derived BM endothelial cells are endowed with the necessary signals to support the self-renewal and regenerative capacity of LT-HSCs and that transplantation of arteriole BM endothelial cells could be used as a therapeutic means to decrease pancytopenias associated with myeloablative treatments to treat a wide array of disease states.