Interleukin 7 receptor is required for myeloid cell homeostasis and reconstitution by hematopoietic stem cells

Abstract The chorio-allantoic placenta provides for the exchange of nutrients, gas, and waste between the fetus and mother. The murine placenta is also enriched for long term repopulating hematopoietic stem cells, and is therefore a stem cell niche (Gekas et al. Dev. Cell8, 365, 2005 and Ottersbach et al. Dev. Cell8, 377, 2005). However, it is not known if the placenta is colonized by hematopoietic stem cells that originate from other sites in the conceptus, or whether the placenta itself is also a site of hematopoietic cell emergence. The placenta is formed through the fusion of the allantois, a mesodermal extension from the primitive streak, with the chorionic plate, which is comprised of extraembryonic ectoderm and mesoderm. Here we show that the allantois and chorion, isolated before chorio-allantoic fusion and prior to the establishment of circulation, contain hematopoietic potential. Both allantois and chorion explants produced CD45 positive cells, some of which also expressed Mac-1 and Gr-1, when cultured on OP9 stromal cells in the presence of cytokines that promote myeloid cell differentiation. Cultures of allantois and chorion explants in the presence of lymphoid promoting cytokines induced B220 and CD19 positive B cells. Spatial and temporal analysis of Runx1, a marker for definitive hematopoiesis, showed Runx1 is not expressed in either the allantois or the chorion prior to fusion, but is expressed at the base of the allantois and at the chorio-allantoic junction following fusion. Both allantoic explant cultures, and cultures of whole embryos from which allantoises were removed in order to prohibit chorio-allantoic fusion showed that Runx1 expression in neither tissue is dependent upon fusion. We conclude that the allantois and chorion have intrinsic hematopoietic potential prior to the establishment of circulation. Our results furthermore suggest that the placenta is both a niche and a source of hematopoietic cells.

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The TLR1/2 agonist PAM3CSK4 instructs commitment of human hematopoietic stem cells to a myeloid cell fate

Leukemia ◽

10.1038/leu.2009.155 ◽

2009 ◽

Vol 23 (11) ◽

pp. 2063-2074 ◽

Cited By ~ 78

Author(s):

K De Luca ◽

V Frances-Duvert ◽

M-J Asensio ◽

R Ihsani ◽

E Debien ◽

...

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Cell Fate ◽

Myeloid Cell ◽

Hematopoietic Stem

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Definitive Hematopoietic Stem Cells Minimally Contribute to Embryonic Hematopoiesis

Blood ◽

10.1182/blood-2021-147998 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 3268-3268

Author(s):

Bianca A Ulloa ◽

Samima S Habbsa ◽

Kathryn S Potts ◽

Alana Lewis ◽

Mia McKinstry ◽

...

Keyword(s):

Stem Cells ◽

Hematopoietic Stem Cells ◽

Conflicts Of Interest ◽

Myeloid Cell ◽

Time Frame ◽

Developmental Differences ◽

Lineage Tracing ◽

Hematopoietic Stem ◽

Temporal Regulation ◽

Batch Correction

Abstract Definitive hematopoietic stem cells (HSCs) emerge in the embryo and sustain major adult hematopoietic lineages. Although their functional potential is detected by transplant, nascent HSC contribution during development is both unknown and difficult to address due to the overlapping emergence of HSC-independent progenitors-cells that lack the multipotency and/or longevity of HSCs but express many of the same markers. Using sorted hematopoietic stem and progenitor cells from zebrafish embryos, we performed single cell RNA sequencing to decipher HSC and HSC-independent progenitor heterogeneity during the time frame of their emergence and initial maturation. After batch correction and dimensional reduction, we identified seven distinct populations that are inferred from RNA velocity analysis to originate from pre-hemogenic endothelium and develop into three main differentiation trajectories. We also determined that HSCs can be distinguished from HSC-independent progenitors based on the temporal regulation and differential activity of the draculin (drl) promoter that was previously shown to mark adult-contributing HSCs. From these studies, we found that the drl promoter is active in HSCs and HSC-independent progenitors at 1-day post-fertilization (dpf) but becomes highly expressed primarily in HSCs by 2 dpf. We applied a drl:cre-ER T2 tamoxifen-inducible Cre-loxP lineage-tracing approach to selectively lineage trace HSCs starting at 2 dpf and track their myeloid and lymphoid contribution during larval development and adulthood. We determined that HSC-independent progenitors primarily contribute to developmental lymphomyelopoiesis with minimal HSC contribution until after 7 dpf. Consistent with this result, we demonstrated that although HSCs robustly regenerated after hematopoietic injury using a novel inducible larval HSC injury model, their depletion had almost no impact on lymphoid and myeloid cell numbers up to 7 dpf. These findings suggest that HSCs are not entirely dormant during development and that there exists an uncoupling of HSC self-renewal and differentiation in development. In conclusion, we determine that it is the HSC-independent progenitors, and not HSCs, that sustain embryonic and early larval lymphomyelopoiesis. Acquiring a greater understanding regarding developmental differences in progenitor and HSC specification and maturation will inform and improve the generation of functional HSCs from renewable pluripotent stem cells. Disclosures No relevant conflicts of interest to declare.

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Early B Cell Differentiation from Hematopoietic Stem Cells in the Presence of Stromal Cells and Interleukin-7 (IL-7)

Experimental Hematology Today—1989 ◽

10.1007/978-1-4613-9003-9_8 ◽

1990 ◽

pp. 45-52

Author(s):

T. Suda ◽

A. Ohara ◽

J. Suda ◽

S. Okada ◽

N. Tokuyama ◽

...

Keyword(s):

Stem Cells ◽

Cell Differentiation ◽

Hematopoietic Stem Cells ◽

B Cell ◽

Stromal Cells ◽

B Cell Differentiation ◽

Hematopoietic Stem ◽

Interleukin 7

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Inducible chronic phase of myeloid leukemia with expansion of hematopoietic stem cells in a transgenic model of BCR-ABL leukemogenesis

Blood ◽

10.1182/blood-2003-12-4369 ◽

2005 ◽

Vol 105 (1) ◽

pp. 324-334 ◽

Cited By ~ 140

Author(s):

Steffen Koschmieder ◽

Berthold Göttgens ◽

Pu Zhang ◽

Junko Iwasaki-Arai ◽

Koichi Akashi ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Hematopoietic Stem Cells ◽

Myeloid Leukemia ◽

Blast Crisis ◽

Chronic Phase ◽

Myeloid Cell ◽

Hematopoietic Stem ◽

Murine Bone Marrow ◽

Multiple Organs

Abstract To develop murine models of leukemogenesis, a series of transgenic mice expressing BCR-ABL in different hematopoietic cell subsets was generated. Here we describe targeted expression of P210 BCR-ABL in stem and progenitor cells of murine bone marrow using the tet-off system. The transactivator protein tTA was placed under the control of the murine stem cell leukemia (SCL) gene 3′ enhancer. Induction of BCR-ABL resulted in neutrophilia and leukocytosis, and the mice became moribund within 29 to 122 days. Autopsy of sick mice demonstrated splenomegaly, myeloid bone marrow hyperplasia, and extramedullary myeloid cell infiltration of multiple organs. BCR-ABL mRNA and protein were detectable in the affected organs. Fluorescence-activated cell sorter (FACS) analysis demonstrated a significant increase in mature and immature myeloid cells in bone marrow and spleen, together with increased bilineal B220+/Mac-1+ cells in the bone marrow. tTA mRNA was expressed in FACS-sorted hematopoietic stem cells expanded 26-fold after BCR-ABL induction. Thirty-one percent of the animals demonstrated a biphasic phenotype, consisting of neutrophilia and subsequent B-cell lymphoblastic disease, reminiscent of blast crisis. In summary, this mouse model recapitulates many characteristics of human chronic myeloid leukemia (CML) and may help elucidate basic leukemogenic mechanisms in CML stem cells during disease initiation and progression. (Blood. 2005;105:324-334)

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Interleukin 7 receptor (IL7R) is required for myeloid cell homeostasis and reconstitution by hematopoietic stem cells

10.1101/2020.09.02.280362 ◽

2020 ◽

Author(s):

Taylor Cool ◽

Atesh Worthington ◽

Donna Poscablo ◽

Adeel Hussaini ◽

E. Camilla Forsberg

Keyword(s):

Stem Cell ◽

Hematopoietic Stem Cell ◽

Myeloid Cell ◽

Lineage Tracing ◽

List Type ◽

Cell Homeostasis ◽

Hematopoietic Stem ◽

Adult Lung ◽

Interleukin 7 ◽

Deficient Mice

AbstractRespiratory diseases are a leading cause of death worldwide, with highly varied vulnerability to disease between individuals. The underlying reasons of disease susceptibility are unknown, but often include a variable immune response in lungs. Recently, we identified a surprising novel role of the interleukin 7 receptor (IL7R), a primarily lymphoid-associated regulator, in fetal-specified, lung-resident macrophage development. Here, we report that traditional, hematopoietic stem cell-derived myeloid cells in the adult lung, peripheral blood, and bone marrow also depend on IL7R expression. Using single and double germline knockout models, we found that eosinophil numbers were reduced upon deletion of IL7Rα. We then employed two Cre recombinase models in lineage tracing experiments to test whether these cells developed through an IL7Rα+ pathway. Despite the impact of IL7Rα deletion, IL7R-Cre labeled only a minimal fraction of eosinophils. We therefore examined the intrinsic versus extrinsic requirement for IL7R in the production of eosinophils using reciprocal hematopoietic stem cell transplantation assays. These assays revealed that extrinsic, but not eosinophil-intrinsic, IL7R is required for eosinophil reconstitution by HSCs in the adult lung. To determine which external factors may be influencing eosinophil development and survival, we performed a cytokine array analysis between wild-type and IL7Rα-deficient mice and found several differentially regulated proteins. These findings expand upon our previous publication that IL7R is required not only for proper lymphoid cell development and homeostasis, but also for myeloid cell homeostasis in tissues.HighlightsLoss of IL7Rα resulted in significantly fewer eosinophils in adult miceIL7R-Cre lineage tracing revealed minimal labeling of eosinophilsIL7Rα-deficient HSCs robustly reconstituted eosinophils in a WT hostWT HSCs failed to fully reconstitute eosinophils in IL7Rα-/- hostsSeveral cytokines are differentially expressed in WT and IL7Rα-deficient mice

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C-MYC Augments the Proliferation and Survival of Hematopoietic Stem Cells and Multipotent Progenitors to Drive Myeloproliferative Neoplasms

Blood ◽

10.1182/blood-2021-146399 ◽

2021 ◽

Vol 138 (Supplement 1) ◽

pp. 28-28

Author(s):

Nicole D. Vincelette ◽

Jungwon Moon ◽

Andrew T. Kuykendall ◽

Ling Zhang ◽

Rami S. Komrokji ◽

...

Keyword(s):

Stem Cells ◽

Cell Proliferation ◽

Hematopoietic Stem Cells ◽

Ex Vivo ◽

Myeloproliferative Neoplasms ◽

Myeloid Cell ◽

Extramedullary Hematopoiesis ◽

Hematopoietic Stem ◽

Multipotent Progenitors ◽

Myeloid Progenitors

Abstract Human genomic studies have identified frequent MYC amplification and copy number gains in myeloid malignancies, and previous studies have shown that MYC plays important roles in survival of Myeloproliferative Neoplasms (MPN) and Acute Myeloid Leukemia (AML) cells. Notably, our recent studies have shown that MYC impairs myeloid cell differentiation and promotes proliferation of myeloid progenitors and AML cells by controlling genomic methylation. However, it is unclear if increased levels of MYC in hematopoietic stem cells (HSCs) and myeloid progenitors is sufficient to provoke the development of MPN or AML and, if so, how this occurs. To addresses these questions we generated Mx1-Cre;Rosa26-LSL-MYC transgenic mouse model that inducibly overexpress MYC following polyinosinic:polycytidylic acid (pIpC) injection and Cre-mediated deletion of loxp-stop-loxp cassette. MYC overexpression was confirmed by qRT-PCR and immunoblot. Complete blood counts (CBC) with differential in the Mx1-Cre +/-;Rosa26-LSL-MYC +/+ mice vs. -MYC +/-or -wild type (WT) littermate mice at week 23 revealed worsening anemia (Hb, 9.6 vs. 16.3 vs. 15.5g/dL, p<0.0001), lymphopenia (73.2 vs. 84.3 vs. 84.5%, p<0.0001), and monocytosis (7.4 vs. 1.8 vs. 0.9%, p=0.0097). Also, bone marrow (BM) cells from the Mx1-Cre +/-;Rosa26-LSL-MYC +/+ mice showed increased monocyte- and granulomonocyte-colony forming potential (CFU-M and CFU-GM), but with limited self-renewal capacity ex vivo (i.e., no CFU after 5 serial plating). Further, inducible MYC overexpression promotes expansion of HSCs (Lin -Sca-1 +cKit + [LSK]), multipotent progenitors (MPPs; LSK CD48 +CD150 -), common myeloid progenitors (CMPs; Lin -Sca1 -cKit +), granulocyte-monocyte progenitors (GMPs; Lin -Sca-1 -cKit +CD34 +FCγR +), and Gr-1/CD11b+ mature myeloid cells, with concomitant reduction of B220+ or CD3+ cells in the BM and spleen. In addition, MYC overexpression provokes splenomegaly (565 vs. 150 vs. 100mg at week 18~22, p<0.0001), extramedullary hematopoiesis with markedly atypical megakaryopoiesis and myeloid preponderance akin to MPN that reduces overall survival (median OS, 157 days vs. not reached vs. not reached, p<0.0001). Collectively, these findings suggest MYC confers enhanced proliferation and survival properties to HSCs and MPPs leading to MPN-like disease. We have shown MYC oncogenic functions in AML cells requires its suppression of TFEB, an mTORC1 regulated bHLH-LZ transcription factor, and that TFEB functions as a tumor suppressor by inducing IDH1/2-TET2 signaling, thus promoting 5-methylcytosine (5mC) to 5-hydroxymethylcytosine (5hmC) conversion in key genes that drive myeloid differentiation and cell death. Similarly, inducible overexpression of MYC in the Mx1-Cre +/-;Rosa26-LSL-MYC +/+ mice significantly reduces the expression of Tfeb, Idh1 and Idh2, and 5hmC levels in both c-Kit + and Cd11b + BM cells. Further, 4-OHT-mediated silencing of Myc in ex vivo cultured BM cells from the Rosa26-CreER T2+/-;Myc fl/fl mice impairs myeloid cell proliferation and robustly induces the expression of Tfeb, Idh1, and Idh2 as well as levels of 5hmC. Finally, inducible TFEB expression in normal 32D.3 myeloid progenitor cells impairs cell proliferation and upregulates 5hmC levels, and these responses are partially reversed by treatment with 2-hydroxyglutarate, an oncometabolite that inhibits 5mC-to-5hmC conversion. Collectively, these findings suggest that the MYC-TFEB-IDH1/2 epigenetic circuit plays a pivotal role in promoting myeloid proliferation to drive the malignant transformation of HSCs to the MPN. Disclosures Kuykendall: Pharmaessentia: Honoraria; Abbvie: Honoraria; Protagonist: Consultancy, Research Funding; Incyte: Consultancy; Blueprint: Honoraria; Celgene/BMS: Honoraria; Novartis: Honoraria, Speakers Bureau. Komrokji: Agios: Honoraria, Speakers Bureau; Acceleron: Honoraria; Geron: Honoraria; Novartis: Honoraria; Abbvie: Honoraria, Speakers Bureau; BMS: Honoraria, Speakers Bureau; JAZZ: Honoraria, Speakers Bureau.

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