Altered microRNA expression links IL6 and TNF-induced inflammaging with myeloid malignancy in humans and mice

Abstract Aging is associated with significant changes in the hematopoietic system, including increased inflammation, impaired hematopoietic stem cell (HSC) function, and increased incidence of myeloid malignancy. Inflammation of aging (“inflammaging”) has been proposed as a driver of age-related changes in HSC function and myeloid malignancy, but mechanisms linking these phenomena remain poorly defined. We identified loss of miR-146a as driving aging-associated inflammation in AML patients. miR-146a expression declined in old wild-type mice, and loss of miR-146a promoted premature HSC aging and inflammation in young miR-146a–null mice, preceding development of aging-associated myeloid malignancy. Using single-cell assays of HSC quiescence, stemness, differentiation potential, and epigenetic state to probe HSC function and population structure, we found that loss of miR-146a depleted a subpopulation of primitive, quiescent HSCs. DNA methylation and transcriptome profiling implicated NF-κB, IL6, and TNF as potential drivers of HSC dysfunction, activating an inflammatory signaling relay promoting IL6 and TNF secretion from mature miR-146a−/− myeloid and lymphoid cells. Reducing inflammation by targeting Il6 or Tnf was sufficient to restore single-cell measures of miR-146a−/− HSC function and subpopulation structure and reduced the incidence of hematological malignancy in miR-146a−/− mice. miR-146a−/− HSCs exhibited enhanced sensitivity to IL6 stimulation, indicating that loss of miR-146a affects HSC function via both cell-extrinsic inflammatory signals and increased cell-intrinsic sensitivity to inflammation. Thus, loss of miR-146a regulates cell-extrinsic and -intrinsic mechanisms linking HSC inflammaging to the development of myeloid malignancy.

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Delineating spatiotemporal and hierarchical development of human fetal innate lymphoid cells

Cell Research ◽

10.1038/s41422-021-00529-2 ◽

2021 ◽

Author(s):

Chen Liu ◽

Yandong Gong ◽

Han Zhang ◽

Hua Yang ◽

Yang Zeng ◽

...

Keyword(s):

Single Cell ◽

Progenitor Cells ◽

Fetal Liver ◽

Innate Lymphoid Cells ◽

Lymphoid Cells ◽

Lymphoid Tissues ◽

Hematopoietic Stem ◽

Molecular Features ◽

Lymphoid Progenitors ◽

B Lineage

AbstractWhereas the critical roles of innate lymphoid cells (ILCs) in adult are increasingly appreciated, their developmental hierarchy in early human fetus remains largely elusive. In this study, we sorted human hematopoietic stem/progenitor cells, lymphoid progenitors, putative ILC progenitor/precursors and mature ILCs in the fetal hematopoietic, lymphoid and non-lymphoid tissues, from 8 to 12 post-conception weeks, for single-cell RNA-sequencing, followed by computational analysis and functional validation at bulk and single-cell levels. We delineated the early phase of ILC lineage commitment from hematopoietic stem/progenitor cells, which mainly occurred in fetal liver and intestine. We further unveiled interleukin-3 receptor as a surface marker for the lymphoid progenitors in fetal liver with T, B, ILC and myeloid potentials, while IL-3RA– lymphoid progenitors were predominantly B-lineage committed. Notably, we determined the heterogeneity and tissue distribution of each ILC subpopulation, revealing the proliferating characteristics shared by the precursors of each ILC subtype. Additionally, a novel unconventional ILC2 subpopulation (CRTH2– CCR9+ ILC2) was identified in fetal thymus. Taken together, our study illuminates the precise cellular and molecular features underlying the stepwise formation of human fetal ILC hierarchy with remarkable spatiotemporal heterogeneity.

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Evidence for a Novel Blood Lineage Commitment Pathway from Lympho-Myeloid Hematopoietic Stem Cells.

Blood ◽

10.1182/blood.v106.11.802.802 ◽

2005 ◽

Vol 106 (11) ◽

pp. 802-802 ◽

Cited By ~ 1

Author(s):

Sten Eirik W. Jacobsen ◽

Robert Mansson ◽

Anne Hultquist ◽

Mikael Sigvardsson ◽

Natalija Buza-Vidas ◽

...

Keyword(s):

Stem Cells ◽

T Cell ◽

Hematopoietic Stem Cells ◽

Single Cell ◽

Lineage Commitment ◽

Mouse Bone Marrow ◽

Differentiation Potential ◽

Hematopoietic Stem ◽

Stage Of Development ◽

Number Of Genes

Abstract We recently identified a novel Lin−Sca-1+c-kithiCD34+Flt3hi (LSKCD34+Flt3hi) lymphoid-primed multipotent progenitor (LMPP) in adult mouse bone marrow which, although possessing a combined lymphoid (B and T cell) and myeloid (granulocyte-monocyte; GM) differentiation potential, have little or no ability to adopt erythroid (E) and megakaryocyte (MK) lineage fates (Adolfsson et al, Cell121:295, 2005). The identification of this lineage restricted lymphomyeloid progenitor implicates the existence of alternative roadmaps for lineage commitment of pluripotent hematopoietic stem cells (HSCs), distinct from the classical model suggesting that the first HSC commitment step results in a strict separation into common lymphoid and myeloid progenitors. Herein we provide further, genetic evidence for such a model. Affymetrix global gene profiling, quantitative PCR, and multiplex single cell PCR analysis of LSKCD34−Flt3− long-term (LT)-HSCs, LSKCD34+Flt3− short-term (ST)-HSCs and LSKCD34+Flt3hi LMPPs, demonstrate that LMPPs in contrast to LT-HSCs and ST-HSCs down-regulate or turn off a number of genes critically involved in MkE lineage development, including GATA-1 and the receptors for erythropoietin and thrombopoietin. In contrast, a number of genes specific for early lymphoid development, including Rag-1, sterile Ig and IL-7 receptor are upregulated in LMPPs but absent in LT-HSCs and ST-HSCs. Importantly, within the LMPP, these lymphoid genes are typically co-expressed with a number of GM associated genes such as G-CSF receptor and MPO, but virtually never co-expressed with MkE associated genes. Investigating fetal liver day 14.5 we also provide evidence for existence of the LSKCD34+Flt3hi LMPPs at this early stage of development, and using a single cell clonal assay promoting combined B, T and myeloid lineage development, we demonstrate that a large fraction of fetal LMPPs lacking MkE potential possess a combined GM, B and T cell potential. Thus, evaluation at the single cell level of combined lineage potentials and multilineage gene expression provide compelling evidence for lymphoid-priming within the HSC compartment being preceeded by a loss of MkE potential, but occurring prior to loss of GM potential.

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Genome Wide DNA Methylation and Transcriptome Analysis in HSC Aging

Blood ◽

10.1182/blood.v118.21.2367.2367 ◽

2011 ◽

Vol 118 (21) ◽

pp. 2367-2367

Author(s):

Mira Jeong ◽

Deqiang Sun ◽

Min Luo ◽

Aysegul Ergen ◽

Hongcang Gu ◽

...

Keyword(s):

Gene Expression ◽

Dna Methylation ◽

Differentially Expressed ◽

Mouse Bone Marrow ◽

Rna Seq ◽

Differentiation Potential ◽

Hematopoietic Stem ◽

Exon Arrays ◽

Age Related ◽

Genome Wide

Abstract Abstract 2367 Hematopoietic stem cell (HSC) Aging is a complex process linked to number of changes in gene expression and functional decline of self-renewal and differentiation potential. While epigenetic changes have been implicated in HSC aging, little direct evidence has been generated. DNA methylation is one of the major underlying mechanisms associated with the regulation of gene expression, but changes in DNA methylation patterns with HSC aging have not been characterized. We hypothesize that revealing the genome-wide DNA methylation and transcriptome signatures will lead to a greater understanding of HSC aging. Here, we report the first genome-scale study of epigenomic dynamics during normal mouse HSC aging. We isolated SP-KSL-CD150+ HSC populations from 4, 12, 24 month-old mouse bone marrow and carried out genome-wide reduced representative bisulfite sequencing (RRBS) and identified aging-associated differentially methylated CpGs. Three biological samples were sequenced from each aging group and we obtained 30–40 million high-quality reads with over 30X total coverage on ∼1.1M CpG sites which gives us adequate statistical power to infer methylation ratios. Bisulfite conversion rate of non-CpG cytosines was >99%. We analyzed a variety of genomic features to find that CpG island promoters, gene bodies, 5'UTRs, and 3'UTRs generally were associated with hypermethylation in aging HSCs. Overall, out of 1,777 differentially methylated CpGs, 92.8% showed age-related hypermethylation and 7.2% showed age-related hypomethylation. Gene ontology analyses have revealed that differentially methylated CpGs were significantly enriched near genes associated with alternative splicing, DNA binding, RNA-binding, transcription regulation, Wnt signaling and pathways in cancer. Most interestingly, over 579 splice variants were detected as candidates for age-related hypermethylation (86%) and hypomethylation (14%) including Dnmt3a, Runx1, Pbx1 and Cdkn2a. To quantify differentially expressed RNA-transcripts across the entire transcriptome, we performed RNA-seq and analyzed exon arrays. The Spearman's correlation between two different methods was good (r=0.80). From exon arrays, we identified 586 genes that were down regulated and 363 gene were up regulated with aging (p<0.001). Most interestingly, overall expression of DNA methyl transferases Dnmt1, Dnmt3a, Dnmt3b were down regulated with aging. We also found that Dnmt3a2, the short isoform of Dnmt3a, which lacks the N-terminal region of Dnmt3a and represents the major isoform in ES cells, is more expressed in young HSC. For the RNA-seq analysis, we focused first on annotated transcripts derived from cloned mRNAs and we found 307 genes were down regulated and 1015 gene were up regulated with aging (p<0.05). Secondly, we sought to identify differentially expressed isoforms and also novel transcribed regions (antisense and novel genes). To characterize the genes showing differential regulation, we analyzed their functional associations and observed that the highest scoring annotation cluster was enriched in genes associated with translation, the immune network and hematopoietic cell lineage. We expect that the results of these experiments will reveal the global effect of DNA methylation on transcript stability and the translational state of target genes. Our findings will lend insight into the molecular mechanisms responsible for the pathologic changes associated with aging in HSCs. Disclosures: No relevant conflicts of interest to declare.

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Age-Associated Characteristics of Murine Hematopoietic Stem Cells

Journal of Experimental Medicine ◽

10.1084/jem.192.9.1273 ◽

2000 ◽

Vol 192 (9) ◽

pp. 1273-1280 ◽

Cited By ~ 477

Author(s):

Kazuhiro Sudo ◽

Hideo Ema ◽

Yohei Morita ◽

Hiromitsu Nakauchi

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Hematopoietic Stem Cells ◽

Bone Marrow Cells ◽

Lymphoid Cells ◽

Differentiation Potential ◽

Self Renewal ◽

Hematopoietic Stem ◽

Functional Changes

Little is known of age-associated functional changes in hematopoietic stem cells (HSCs). We studied aging HSCs at the clonal level by isolating CD34−/lowc-Kit+Sca-1+ lineage marker–negative (CD34−KSL) cells from the bone marrow of C57BL/6 mice. A population of CD34−KSL cells gradually expanded as age increased. Regardless of age, these cells formed in vitro colonies with stem cell factor and interleukin (IL)-3 but not with IL-3 alone. They did not form day 12 colony-forming unit (CFU)-S, indicating that they are primitive cells with myeloid differentiation potential. An in vivo limiting dilution assay revealed that numbers of multilineage repopulating cells increased twofold from 2 to 18 mo of age within a population of CD34−KSL cells as well as among unseparated bone marrow cells. In addition, we detected another compartment of repopulating cells, which differed from HSCs, among CD34−KSL cells of 18-mo-old mice. These repopulating cells showed less differentiation potential toward lymphoid cells but retained self-renewal potential, as suggested by secondary transplantation. We propose that HSCs gradually accumulate with age, accompanied by cells with less lymphoid differentiation potential, as a result of repeated self-renewal of HSCs.

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Myeloid Lineage Restriction Is Prior to and Independent of Lymphoid Lineage Restriction.

Blood ◽

10.1182/blood.v108.11.4174.4174 ◽

2006 ◽

Vol 108 (11) ◽

pp. 4174-4174

Author(s):

Azusa Matsubara ◽

Jun Ooehara ◽

Yuji Yamazaki ◽

Hina Takano ◽

Hiromitsu Nakauchi ◽

...

Keyword(s):

Single Cell ◽

Lineage Commitment ◽

Mouse Bone Marrow ◽

Short Term ◽

Differentiation Potential ◽

Myeloid Lineage ◽

Hematopoietic Stem ◽

Lymphoid Lineage ◽

Branched Point

Abstract It has been widely accepted that hematopoietic stem cells (HSCs) exclusively give rise to either myeloid or lymphoid lineage along their differentiation. Phenotypically defined as FcRloCD34+IL-7R−Sca-1−Kit+Lin− cells, common myeloid progenitors (CMPs) are supposedly at the first branched point for myeloid lineage commitment. Phenotypically defined as Thy1.1−IL-7R+KitloSca-1loLin− cells, common lymphoid progenitors are supposedly at the first branched point for both B- and T-lymphoid lineage commitment. Contradicting this model, we previously made observations of the myeloid lineage restriction in very early stages of HSC differentiation. We therefore decided to compare the myeloid and lymphoid differentiation potentials in long-term HSCs, short-term HSCs, multipotent progenitors (MPPs), CMPs, granulocyte/macrophage progenitors (GMPs), megakaryocyte/erythrocyte progenitors (MEPs), and CLPs at the single cell level. Because any available assays are not so sensitive enough for detection of lymphoid lineage differentiation potential, we primarily focused on myeloid differentiation potentials in this study. Here we provide data indicative of the absence of CMPs in the adult mouse bone marrow. Long-term HSCs (CD34−Kit+Sca-1+Lin− cells), short-term HSCs (Flt-3−CD34+Kit+Sca-1+Lin− cells), MPPs (Flt-3+CD34+Kit+Sca-1+Lin− cells), CMPs (FcRloCD34+IL-7R−Sca-1−Kit+Lin− cells), GMPs (FcRhiCD34+IL-7R−Sca-1−Kit+Lin− cells), MEPs (FcRloCD34−IL-7R−Sca-1−Kit+Lin− cells), and CLPs (IL-7R+KitloSca-1loLin− cells) were purified from adult B6 mice by flow cytometry. Single cell cultures were performed in the presence of SCF+TPO+IL-3+EPO. All colonies made by single cells were subjected to Cytospin preparations, followed by May-Gruenwald-Giemsa staining, for morphological classifications of colony cells: neutrophil (n), macrophage (m), erythroblast (E), or megakaryocyte (M). Cells with all n, m, E, M differentiation potentials (nmEM cells) were detected in on average 31%, 5%, and fewer than 1 % of long-term HSCs, short-term HSCs, and MPPs, repectively. Notably, none of a total of over 800 CMPs showed the full nmEM differentiation potential. These CMPs instead showed potentials belonging to members of GMPs and MEPs, suggesting CMPs are mostly an overlaping population of GMPs and MEPs rather than a distinct population. Single cell transplantation experiments revealed the coexistence of cells with the myleoid and B-lymphoid potentials or cells with the myeloid and T-lymphoid potentials among CD34−Kit+Sca-1+Lin− long-term HSC population. These progentiors are likely to be immediate progeny of HSCs. Together, these data support our view that myeloid lineage restriction takes place prior to and independent of lymphoid lineage restriction.

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Adult mouse hematopoietic stem cells: purification and single-cell assays

Nature Protocols ◽

10.1038/nprot.2006.447 ◽

2006 ◽

Vol 1 (6) ◽

pp. 2979-2987 ◽

Cited By ~ 131

Author(s):

Hideo Ema ◽

Yohei Morita ◽

Satoshi Yamazaki ◽

Azusa Matsubara ◽

Jun Seita ◽

...

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Single Cell ◽

Adult Mouse ◽

Hematopoietic Stem ◽

Cell Assays

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Notch signaling distinguishes 2 waves of definitive hematopoiesis in the zebrafish embryo

Blood ◽

10.1182/blood-2009-09-244590 ◽

2010 ◽

Vol 115 (14) ◽

pp. 2777-2783 ◽

Cited By ~ 72

Author(s):

Julien Y. Bertrand ◽

Jennifer L. Cisson ◽

David L. Stachura ◽

David Traver

Keyword(s):

Notch Signaling ◽

Butyl Ester ◽

Receptor Activation ◽

Notch Receptor ◽

Lymphoid Cells ◽

Phenotypic Traits ◽

Differentiation Potential ◽

Hematopoietic Stem ◽

Mature Adult ◽

Definitive Hematopoiesis

Abstract Recent studies have revealed that definitive hematopoiesis in vertebrates initiates through the formation of a non–self-renewing progenitor with limited multilineage differentiation potential termed the erythromyeloid progenitor (EMP). EMPs are specified before hematopoietic stem cells (HSCs), which self-renew and are capable of forming all mature adult blood lineages including lymphoid cells. Despite their differences, EMPs and HSCs share many phenotypic traits, making precise study of their respective functions difficult. Here, we examine whether embryonic specification of EMPs requires Notch signaling as has been shown for HSCs. In mindbomb mutants, which lack functional Notch ligands, we show that EMPs are specified normally: we detect no significant differences in cell number, gene expression, or differentiation capacity between EMPs purified from wild-type (WT) or mindbomb mutant embryos. Similarly N-[N-(3,5-difluorophenacetyl)-l-alanyl]-S-phenylglycine t-butyl ester (DAPT), a chemical inhibitor of Notch receptor activation, has no effect on EMP specification. These studies establish that HSCs are the only hematopoietic precursor that requires Notch signaling and help to clarify the signaling events underlying the specification of the 2 distinct waves of definitive hematopoiesis.

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Single Cell-Resolution Analysis of HSC Dysfunction in Mir-146a knockout Mice

Blood ◽

10.1182/blood.v130.suppl_1.714.714 ◽

2017 ◽

Vol 130 (Suppl_1) ◽

pp. 714-714

Author(s):

Jennifer Grants ◽

Joanna Wegrzyn ◽

David Knapp ◽

Tony Hui ◽

Kieran O'Neill ◽

...

Keyword(s):

Cell Cycle ◽

Single Cell ◽

Transcriptome Profiling ◽

Self Renewal ◽

Hematopoietic Stem ◽

Proliferation And Differentiation ◽

Stem And Progenitor Cells ◽

Resolution Analysis ◽

Signaling Activation

Abstract MicroRNA miR-146a is frequently depleted in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Loss of miR-146a may be an initiating event in tumorigenesis, as miR-146a loss in mouse models is sufficient to cause features of MDS and eventual progression to AML. To define how miR-146a loss initiates tumorigenesis, we analyzed hematopoietic stem cell (HSC) function from miR-146a knockout (KO) mice prior to onset of an overt malignant phenotype. Tracking cell division kinetics, proliferation, and differentiation of single long-term HSC (LT-HSC; EPCR+CD45+CD48-CD150+) in culture, we found evidence that miR-146a KOreduces HSC quiescence and promotes differentiating cell divisions. Our data show that miR-146a KO HSC dysfunction may stem from loss of a CD150-bright EPCR-bright sub-population, which has previously been associated with robust HSC activity. In line with this, single cell DNA methylation profiling revealed a reduction in a primitive sub-population of LT-HSCs in miR-146a KO animals. In addition, single cell LT-HSC transplants revealed a myeloid repopulation bias. As reduced HSC cell cycle quiescence has been linked to impaired HSC self-renewal upon hematopoietic stress, such as serial transplantation, we assessed the frequency of serially transplantable HSCs by performing secondary transplants with limiting dilution. Serially transplantable HSC frequency was reduced in miR-146a KO compared to wild type, suggesting impaired HSC self-renewal. Transcriptome profiling of miR-146a KO hematopoietic stem and progenitor cells identified tumor necrosis factor (TNF) signaling activation as a potential driver of HSC dysfunction. LT-HSC cell cycle quiescence and the CD150-bright EPCR-bright LT-HSC sub-population were restored in miR-146a/TNF double KO mice, suggesting that aberrant TNF signaling activation drives HSC dysfunction upon loss of miR-146a. Gene expression levels in the TNF signaling network are inversely correlated with miR-146a levels in human AML, implying that TNF signaling may similarly disrupt HSC function in miR-146a- depleted myeloid malignancies. Overall, our findings suggest that miR-146a promotes HSC cell cycle quiescence and inhibits differentiation by antagonizing TNF signaling, in order to maintain a primitive sub-population of long-term self-renewing HSCs. Disclosures Eaves: Experimental Hematology: Other: Editor of journal; StemCell Technologies Inc: Other: Wife of owner.

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A Platform for the Scalable Derivation of Genetically-Enhanced T and NK Lymphocytes from Naive Human Induced Pluripotent Stem Cells for Cancer Immunotherapy

Blood ◽

10.1182/blood.v126.23.2364.2364 ◽

2015 ◽

Vol 126 (23) ◽

pp. 2364-2364

Author(s):

Raedun Clarke ◽

William Kim ◽

Brian Groff ◽

Ramzey Abujarour ◽

Megan Robinson ◽

...

Keyword(s):

Stem Cells ◽

Nk Cells ◽

Single Cell ◽

Cancer Immunotherapy ◽

Small Molecule ◽

Lymphoid Cells ◽

Scale Production ◽

Hematopoietic Stem ◽

Induced Pluripotent

Abstract Human induced pluripotent stem cell (hiPSC) technology enables the generation of a potentially unlimited source of therapeutically viable hematopoietic cells for the treatment of numerous hematological and non-hematological malignancies, and represents a highly promising approach for overcoming many of the challenges and limitations of patient-derived cancer immunotherapies. To advance the promise of hiPSC technology as an "off-the-shelf" source of hematopoietic cellular therapeutics, it is essential to be able to efficiently and reproducibly generate not only hematopoietic stem cells (HSCs) but also immune effector populations, including the diverse subsets of T and NK lymphoid cells, through a robust and scalable process. The in vitro derivation of HSCs and lymphocytes is complicated by the existence of at least two temporally and spatially distinct waves of blood cell formation during embryonic development: primitive and definitive. Primitive hematopoiesis initiates in the extraembryonic yolk sac and generates a transient and restricted hematopoietic repertoire consisting mainly of primitive erythroid and myeloid cells. Nascent HSCs only emerge later during the definitive wave from a specialized endothelial progenitor within the arterial vasculature termed hemogenic endothelium (HE). HE undergoes an endothelial-to-hematopoietic transition to give rise to HSCs, which then ultimately migrate to the bone marrow where they sustain multi-lineage hematopoiesis, including T and NK lymphoid cells, throughout adult life. Therefore the generation of HSCs and the formation of lymphoid effector cells from hiPSCs is dependent upon our ability to accurately recapitulate the intricate stages of early embryonic hematopoietic development towards the definitive program. While a limited number of studies have described the directed differentiation of hiPSCs to definitive HE in vitro, a major hurdle in utilizing hiPSCs for therapeutic purposes has been the requirement to initially co-culture such cells with murine-derived stromal cells in the presence of ill-defined serum-containing media in order to maintain pluripotency and induce differentiation. In addition, these protocols have employed an intermediate strategy consisting of embryoid body (EB) formation, which is difficult to scale and hindered by lack of reproducibility. We have previously demonstrated that our proprietary platform for robust and rapid derivation of clonal hiPSC lines, which utilizes small molecule reprograming and single cell selection strategies, generates cells with properties indicative of the naïve, or ground state of pluripotency. In addition to maintaining a homogeneous population of hiPSCs, our platform enables the genetic engineering of such pluripotent cells, at a single cell level, in both nuclease-dependent and -independent strategies. Here we describe a novel method for the generation of definitive HE from naïve hiPSCs in a scalable manner, void of an EB intermediate, under serum/feeder-free conditions. This platform represents a well-defined, small molecule-driven, staged protocol that can readily be translated to meet current good manufacturing practice (cGMP) requirements for the development of "off-the-shelf" hematopoietic cell-based immunotherapies. The derived HE population is definitive in nature as determine by Notch dependency and exhibits multi-lineage potential, as demonstrated through the formation of both T and NK lymphoid cells. HE generated by this protocol can be successfully cryopreserved and banked, serving as a highly-stable feedstock for subsequent derivation of various cell types for therapeutic use, including for T and NK cell-based immunotherapies. We have demonstrated that our proprietary, clinically-adaptable method for the large-scale production of definitive HE can efficiently give rise to a variety of lymphoid cell subsets. These derived lymphocytes, including NK cells, have been extensively characterized in vitro and in vivo, and we have demonstrated functionality through cytokine release and cellular cytotoxicity. Furthermore, through genetic modifications at the single cell hiPSC stage, tumor antigen-targeting and inducible caspase-mediated safety systems have been introduced into safe harbor loci to improve the specificity and safety profiles of hiPSC-derived T and NK cells for cancer immunotherapy applications. Disclosures Clarke: Fate Therapeutics Inc: Employment. Abujarour:Fate Therapeutics Inc: Employment. Robinson:Fate Therapeutics Inc: Employment. Huang:Fate Therapeutics Inc: Employment. Shoemaker:Fate Therapeutics Inc: Employment. Valamehr:Fate Therapeutics Inc: Employment.

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Single-cell transcriptomic landscape of human blood cells

National Science Review ◽

10.1093/nsr/nwaa180 ◽

2020 ◽

Author(s):

Xiaowei Xie ◽

Mengyao Liu ◽

Yawen Zhang ◽

Bingrui Wang ◽

Caiying Zhu ◽

...

Keyword(s):

Single Cell ◽

Human Blood ◽

Blood Cells ◽

Regulatory Networks ◽

Cell Types ◽

Lymphoid Cells ◽

Immune Functions ◽

Hematopoietic Stem ◽

Molecular Features ◽

Human Blood Cells

Abstract High throughput single-cell RNA-seq has been successfully implemented to dissect the cellular and molecular features underlying hematopoiesis. However, an elaborate and comprehensive transcriptome reference of the whole blood system is lacking. Here, we profiled the transcriptomes of 7551 human blood cells representing 32 immunophenotypic cell types, including hematopoietic stem cells, progenitors and mature blood cells derived from 21 healthy donors. With high sequencing depth and coverage, we constructed a single-cell transcriptional atlas of blood cells (ABC) on the basis of both protein-coding genes and long noncoding RNAs (lncRNAs), and showed a high consistence between them. Notably, putative lncRNAs and transcription factors regulating hematopoietic cell differentiation were identified. While common transcription factor regulatory networks were activated in neutrophils and monocytes, lymphoid cells dramatically changed their regulatory networks during differentiation. Furthermore, we showed a subset of nucleated erythrocytes actively expressing immune signals, suggesting the existence of erythroid precursors with immune functions. Finally, a web portal offering transcriptome browsing and blood cell type prediction has been established. Thus, our work provides a transcriptional map of human blood cells at single-cell resolution, thereby offering a comprehensive reference for the exploration of physiological and pathological hematopoiesis.

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