Single-cell analysis reveals the KIT D816V mutation in hematopoietic stem and progenitor cells in systemic mastocytosis: Supplementary data

Background: Systemic mastocytosis (SM) is a hematological disease characterized by organ infiltration by neoplastic mast cells. Almost all SM patients have a mutation in the gene encoding the tyrosine kinase receptor KIT causing a D816V substitution and autoactivation of the receptor. Mast cells and CD34+ hematopoietic progenitors can carry the mutation, however, in which progenitor cell subset the mutation arises is unknown. We aimed to investigate the distribution of the D816V mutation in single mast cells and single hematopoietic stem and progenitor cells. Methods: Fluorescence-activated single-cell index sorting and D816V mutation assessment were applied to analyze mast cells and more than 10,000 CD34+ bone marrow progenitors across 10 hematopoietic progenitor subsets. In vitro assays verified cell-forming potential. Findings: We found that in SM 60-99% of the mast cells harbored the D816V mutation. Despite increased frequencies of mast cells in SM patients compared with control subjects, the hematopoietic progenitor subset frequencies were comparable. Nevertheless, the mutation could be detected throughout the hematopoietic landscape of SM patients, from hematopoietic stem cells to more lineage-primed progenitors. In addition, we demonstrate that FcεRI+ bone marrow progenitors exhibit mast cell-forming potential, and we describe aberrant CD45RA expression on SM mast cells for the first time. Interpretation: The KIT D816V mutation arises in early hematopoietic stem and progenitor cells and the mutation frequency is approaching 100% in mature mast cells, which express the aberrant marker CD45RA.

Download Full-text

Sociology of Normal Stem and Progenitor Cells in CML Niche

Blood ◽

10.1182/blood.v120.21.1234.1234 ◽

2012 ◽

Vol 120 (21) ◽

pp. 1234-1234

Author(s):

Robert S Welner ◽

Giovanni Amabile ◽

Deepak Bararia ◽

Philipp B. Staber ◽

Akos G. Czibere ◽

...

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Mouse Model ◽

Progenitor Cells ◽

Conflicts Of Interest ◽

Hematopoietic Progenitor Cells ◽

Quiescent State ◽

Hematopoietic Progenitor ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells

Abstract Abstract 1234 Specialized bone marrow (BM) microenvironment niches are essential for hematopoietic stem and progenitor cell maintenance, and recent publications have focused on the leukemic stem cells interaction and placement within those sites. Surprisingly, little is known about how the integrity of this leukemic niche changes the normal stem and progenitor cells behavior and functionality. To address this issue, we started by studying the kinetics and differentiation of normal hematopoietic stem and progenitor cells in mice with Chronic Myeloid Leukemia (CML). CML accounts for ∼15% of all adult leukemias and is characterized by the BCR-ABL t(9;22) translocation. Therefore, we used a novel SCL-tTA BCR/ABL inducible mouse model of CML-chronic phase to investigate these issues. To this end, BM from leukemic and normal mice were mixed and co-transplanted into hosts. Although normal hematopoiesis was increasingly suppressed during the disease progression, the leukemic microenvironment imposed distinct effects on hematopoietic progenitor cells predisposing them toward the myeloid lineage. Indeed, normal hematopoietic progenitor cells from this leukemic environment demonstrated accelerated proliferation with a lack of lymphoid potential, similar to that of the companion leukemic population. Meanwhile, the leukemic-exposed normal hematopoietic stem cells were kept in a more quiescent state, but remained functional on transplantation with only modest changes in both engraftment and homing. Further analysis of the microenvironment identified several cytokines that were found to be dysregulated in the leukemia and potentially responsible for these bystander responses. We investigated a few of these cytokines and found IL-6 to play a crucial role in the perturbation of normal stem and progenitor cells observed in the leukemic environment. Interestingly, mice treated with anti-IL-6 monoclonal antibody reduced both the myeloid bias and proliferation defects of normal stem and progenitor cells. Results obtained with this mouse model were similarly validated using specimens obtained from CML patients. Co-culture of primary CML patient samples and GFP labeled human CD34+CD38- adult stem cells resulted in selective proliferation of the normal primitive progenitors compared to mixed cultures containing unlabeled normal bone marrow. Proliferation was blocked by adding anti-IL-6 neutralizing antibody to these co-cultures. Therefore, our current study provides definitive support and an underlying crucial mechanism for the hematopoietic perturbation of normal stem and progenitor cells during leukemogenesis. We believe our study to have important implications for cancer prevention and novel therapeutic approach for leukemia patients. We conclude that changes in cytokine levels and in particular those of IL-6 in the CML microenvironment are responsible for altered differentiation and functionality of normal stem cells. Disclosures: No relevant conflicts of interest to declare.

Download Full-text

Histidine Decarboxylase (HDC) as Novel Marker of Immature Neoplastic Mast Cells in Systemic Mastocytosis.

Blood ◽

10.1182/blood.v104.11.4755.4755 ◽

2004 ◽

Vol 104 (11) ◽

pp. 4755-4755

Author(s):

Maria T. Krauth ◽

Hermine Agis ◽

Karl J. Aichberger ◽

Ingrid Simonitsch ◽

Leonhard Muellauer ◽

...

Keyword(s):

Bone Marrow ◽

Mast Cells ◽

Progenitor Cells ◽

Histidine Decarboxylase ◽

Systemic Mastocytosis ◽

Bone Marrow Involvement ◽

Hematopoietic Progenitor Cells ◽

Pcr Analysis ◽

Maturation Stage ◽

Hematopoietic Progenitor

Abstract Synthesis of histamine in hematopoietic progenitor cells may be one of the earliest events in mast cell-development from pluripotent hematopoietic progenitor cells. In the present study, we asked whether the key enzyme involved in histamine generation, histidine decarboxylase (HDC), can be employed as an immunohistochemical marker for the detection of (neoplastic) mast cells (MC) in patients with cutaneous (CM) or systemic mastocytosis (SM). To address this question, we examined bone marrow biopsy specimens in a cohort of 101 patients (CM, n=10; indolent SM, n=46; SM with associated clonal non-MC lineage disease, n=31; aggressive SM, n=10; MC leukemia, n=3; MC sarcoma, n=1) using an antibody against HDC. Independent of the maturation stage of MC or subtype of disease, the anti-HDC antibody produced clear diagnostic staining results in all patients with bone marrow involvement examined including those with MC leukemia and MC sarcoma, in which MC are particularly immature and often escape analysis when examined by conventional stains. In these patients (MC leukemia, n=2; MC sarcoma, n=1), expression of HDC was reconfirmed at the mRNA level by RT-PCR analysis performed with RNA of highly enriched sorted CD117+ MC. In patients with CM or normal/reactive bone marrow (n=30), no HDC-positive infiltrates were detected. In these patients, only a few hematopoietic cells, presumably basophils, were found to react with the anti-HDC antibody. In summary, HDC is expressed in neoplastic bone marrow MC in patients with SM independent of the maturation stage of cells or the variant of disease. HDC should therefore be considered as a new MC marker in the screen panel of antigens employed to diagnose high grade MC malignancies.

Download Full-text

The Neurotransmitter Receptor Gabbr1 Regulates Proliferation and Function of Hematopoietic Stem and Progenitor Cells

Blood ◽

10.1182/blood-2019-130627 ◽

2019 ◽

Vol 134 (Supplement_1) ◽

pp. 3707-3707

Author(s):

Adedamola Elujoba-Bridenstine ◽

Lijian Shao ◽

Katherine Zink ◽

Laura Sanchez ◽

Brian Cox ◽

...

Keyword(s):

Bone Marrow ◽

Single Cell ◽

Progenitor Cells ◽

Gene Set Enrichment Analysis ◽

Mouse Bone Marrow ◽

Type I ◽

Rna Seq ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

And Behavior

Hematopoietic stem and progenitor cells (HSPCs) have multi-lineage potential and can be used in transplants as a curative treatment for various hematopoietic diseases. HSPC function and behavior is tightly regulated by various cell types and factors in the bone marrow niche. One level of regulation comes from the sympathetic nervous system that innervates the niche and releases neurotransmitters to stromal cells. However, the direct regulation of HSPCs via cell surface expression of neural receptors has not been functionally explored. Using imaging mass spectrometry, we detected strong and regionally specific gamma-aminobutyric acid (GABA) neurotransmitter signal in the endosteal region of mouse bone marrow. GABBR1 is known to be expressed on human HSPCs (Steidl et al., Blood 2004), however its function in their regulation has not been investigated. Based on published mouse HSPC single cell RNA-seq data (Nestorowa et al., Blood 2016), we found that a subset of HSPCs expressed the GABA type B receptor subunit 1 (Gabbr1). We confirmed by surface receptor expression that a subset of mouse bone marrow HSPCs express Gabbr1 protein. Using the same single cell RNA-seq data as above, our own gene set enrichment analysis (GSEA) revealed positive correlation of Gabbr1 expression with genes involved in immune system processes, such as response to type I interferons. We generated a CRISPR-Cas9 Gabbr1 mutant mouse model on a C57/BL6 background suitable for hematopoietic studies. Analysis of Gabbr1 mutant bone marrow cells revealed a reduction in the absolute number of Lin-Sca1+cKit+ (LSK) HSPCs, but no change in the number of long-term hematopoietic stem cells (LT-HSCs). With further hematopoietic profiling, we discovered reduced numbers of white blood cells in peripheral blood that was primarily due to fewer B220+ cells. We show that Gabbr1 null HSPCs display reduced proliferative capacity, as well as diminished reconstitution ability when transplanted in a competitive setting. An in vitro differentiation assay revealed the impaired ability of Gabbr1 null HSPCs to produce B cell lineages. We tested our predicted association with type I interferon response by administration of poly(I:C) and found reduced HSPC proliferation in Gabbr1 null mice. Our results may translate well to humans, as a rare human SNP within the GABBR1 locus was found that correlates with altered leukocyte counts (Astle et al., Cell 2016). Our results indicate an important role for Gabbr1 in the regulation of HSPC proliferation and differentiation, highlighting Gabbr1 as an emerging factor in the modulation of HSPC function and behavior. Disclosures No relevant conflicts of interest to declare.

Download Full-text

A Meta-Analytic Single-Cell Atlas of Mouse Bone Marrow Hematopoietic Development

10.1101/2021.08.12.456098 ◽

2021 ◽

Author(s):

Benjamin D Harris ◽

John Lee ◽

Jesse Gillis

Keyword(s):

Bone Marrow ◽

Single Cell ◽

Progenitor Cells ◽

Cell Types ◽

Marker Genes ◽

Mouse Bone Marrow ◽

Clear Understanding ◽

Hematopoietic Stem ◽

Hematopoietic Development ◽

Stem And Progenitor Cells

The clinical importance of the hematopoietic system makes it one of the most heavily studied lineages in all of biology. A clear understanding of the cell types and functional programs during hematopoietic development is central to research in aging, cancer, and infectious diseases. Known cell types are traditionally identified by the expression of proteins on the surface of the cells. Stem and progenitor cells defined based on these markers are assigned functions based on their lineage potential. The rapid growth of single cell RNA sequencing technologies (scRNAseq) provides a new modality for evaluating the cellular and functional landscape of hematopoietic stem and progenitor cells. The popularity of this technology among hematopoiesis researchers enables us to conduct a robust meta-analysis of mouse bone marrow scRNAseq data. Using over 300,000 cells across 12 datasets, we evaluate the classification and function of cell types based on discrete clustering, in silico FACS sorting, and a continuous trajectory. We identify replicable signatures that define cell types based on genes and known cellular functions. Additionally, we evaluate the conservation of signatures associated with erythroid and monocyte lineage development across species using co-expression networks. The co-expression networks predict the effectiveness of the signature at identifying erythroid and monocyte cells in zebrafish and human scRNAseq data. Together, this analysis provides a robust reference, particularly marker genes and functional annotations, for future experiments in hematopoietic development.

Download Full-text

Faculty Opinions recommendation of Bone marrow CD169+ macrophages promote the retention of hematopoietic stem and progenitor cells in the mesenchymal stem cell niche.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.11493958.12528059 ◽

2011 ◽

Author(s):

Devendra Agrawal ◽

Vineet Agrawal

Keyword(s):

Bone Marrow ◽

Stem Cell ◽

Mesenchymal Stem Cell ◽

Progenitor Cells ◽

Stem Cell Niche ◽

Hematopoietic Stem ◽

Stem And Progenitor Cells ◽

Cell Niche

Download Full-text

Mechanism of Action of Diallyl Sulphide in Ameliorating the Hematopoietic Radiation Injury

Journal of Health and Allied Sciences NU ◽

10.1055/s-0041-1730094 ◽

2021 ◽

Author(s):

Omika Katoch ◽

Mrinalini Tiwari ◽

Namita Kalra ◽

Paban K. Agrawala

Keyword(s):

Stem Cells ◽

Bone Marrow ◽

Progenitor Cells ◽

Hematopoietic Stem ◽

Proliferation And Differentiation ◽

Stem And Progenitor Cells ◽

Radiation Induced ◽

Medicinal Properties ◽

Marrow Cellularity

AbstractDiallyl sulphide (DAS), the pungent component of garlic, is known to have several medicinal properties and has recently been shown to have radiomitigative properties. The present study was performed to better understand its mode of action in rendering radiomitigation. Evaluation of the colonogenic ability of hematopoietic progenitor cells (HPCs) on methocult media, proliferation and differentiation of hematopoietic stem cells (HSCs), and transplantation of stem cells were performed. The supporting tissue of HSCs was also evaluated by examining the histology of bone marrow and in vitro colony-forming unit–fibroblast (CFU-F) count. Alterations in the levels of IL-5, IL-6 and COX-2 were studied as a function of radiation or DAS treatment. It was observed that an increase in proliferation and differentiation of hematopoietic stem and progenitor cells occurred by postirradiation DAS administration. It also resulted in increased circulating and bone marrow homing of transplanted stem cells. Enhancement in bone marrow cellularity, CFU-F count, and cytokine IL-5 level were also evident. All those actions of DAS that could possibly add to its radiomitigative potential and can be attributed to its HDAC inhibitory properties, as was observed by the reversal radiation induced increase in histone acetylation.

Download Full-text