Deciphering cell states and genealogies of human hematopoiesis with single-cell multi-omics [Young2]
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ABSTRACT: The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:The human blood system is maintained through the differentiation and massive amplification of a limited number of long-lived hematopoietic stem cells (HSCs). Perturbations to this process underlie a diverse set of diseases, but the clonal contributions to human hematopoiesis and how this changes with age remain incompletely understood. While recent insights have emerged from barcoding studies in model systems, simultaneous detection of cell states and phylogenies from natural barcodes in humans has been challenging, which has limited the ability to explore functional differences between HSC clones. Here, we introduce an improved single-cell lineage tracing system based on deep detection of naturally-occurring mitochondrial DNA (mtDNA) mutations with simultaneous readout of transcriptional states and chromatin accessibility. We use this system to define the clonal architecture of HSCs, and map the physiological state and output of these clones. We uncover functional heterogeneity in HSC clones, which is stable over months and manifests as differences in total HSC output as well as biases toward the production of different mature blood and immune lineages. We also find that the diversity of HSC clones decreases dramatically with age leading to an oligoclonal structure with multiple distinct clonal expansions. Our study thus provides the first clonally-resolved and cell-state aware atlas of human hematopoiesis at single-cell resolution revealing an unappreciated functional diversity of human HSC clones both in young and aged individuals and more broadly paves the way for refined studies of clonal dynamics across a range of tissues in human health and disease.
Project description:<p>Hematopoietic stem cell (HSC) mutations can result in clonal hematopoiesis (CH) with heterogeneous clinical outcomes. Here, we investigated how the cell state preceding <em>Tet2</em> mutation impacts the pre-malignant phenotype. Using an inducible system for clonal analysis of myeloid progenitors, we found that the epigenetic features of clones at similar differentiation status were highly heterogeneous and functionally responded differently to <em>Tet2</em> mutation. Cell differentiation stage also influenced <em>Tet2</em> mutation response indicating that the cell of origin's epigenome modulates clone-specific behaviors in CH. Molecular features associated with higher risk outcomes include <em>Sox4</em> that sensitized cells to <em>Tet2</em> inactivation, inducing dedifferentiation, altered metabolism and increasing the <em>in vivo</em> clonal output of mutant cells, as confirmed in primary GMP and HSC models. Our findings validate the hypothesis that epigenetic features can predispose specific clones for dominance, explaining why identical genetic mutations can result in different phenotypes.</p>
Project description:Clonal hematopoiesis of aging results from enhanced fitness of mutant hematopoietic stem cells (HSCs) and associates with both favorable and unfavorable health outcomes related to lineage cell types produced by mutant HSCs. The extent to which lineage output can be controlled in clonal hematopoiesis is unknown. Using a mouse model of DNMT3AR882/+ clonal hematopoiesis (Dnmt3aR878H/+), we find that aging-induced TNFα signaling drives selective advantage of mutant HSCs concomitant with B lymphoid lineage production. Genetic loss of TNFα receptor TNFR1 impaired mutant HSC fitness while loss of TNFR2 abrogated lymphoid production and resulted in unrestrained myeloid cell production from mutant HSCs. These results support a model where clone size and lineage output can be independently targeted to harness potential beneficial aspects of clonal hematopoiesis.
Project description:Clonal hematopoiesis resulting from enhanced fitness of mutant hematopoietic stem cells (HSCs) associates with both favorable and unfavorable health outcomes related to the types of mature mutant blood cells produced, but how this lineage output is regulated is unclear. Using a mouse model of DNMT3AR882/+ clonal hematopoiesis (Dnmt3aR878H/+), we found that aging-induced TNFα signaling promoted the selective advantage of mutant HSCs as well as stimulated mutant B lymphoid cell production. Genetic loss of TNFα receptor TNFR1 impaired mutant HSC fitness without altering lineage output, while loss of TNFR2 reduced lymphoid cell production and favored myeloid cell production from mutant HSCs without altering overall fitness. These results support a model where clone size and mature blood lineage production can be independently controlled to harness potential beneficial aspects of clonal hematopoiesis.