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Kim Y, Calderon AA, Favaro P, Glass DR, Tsai AG, Ho D, Borges L, Greenleaf WJ, Bendall SC. Terminal deoxynucleotidyl transferase and CD84 identify human multi-potent lymphoid progenitors. Nat Commun 2024; 15:5910. [PMID: 39003273 PMCID: PMC11246490 DOI: 10.1038/s41467-024-49883-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 06/24/2024] [Indexed: 07/15/2024] Open
Abstract
Lymphoid specification in human hematopoietic progenitors is not fully understood. To better associate lymphoid identity with protein-level cell features, we conduct a highly multiplexed single-cell proteomic screen on human bone marrow progenitors. This screen identifies terminal deoxynucleotidyl transferase (TdT), a specialized DNA polymerase intrinsic to VDJ recombination, broadly expressed within CD34+ progenitors prior to B/T cell emergence. While these TdT+ cells coincide with granulocyte-monocyte progenitor (GMP) immunophenotype, their accessible chromatin regions show enrichment for lymphoid-associated transcription factor (TF) motifs. TdT expression on GMPs is inversely related to the SLAM family member CD84. Prospective isolation of CD84lo GMPs demonstrates robust lymphoid potentials ex vivo, while still retaining significant myeloid differentiation capacity, akin to LMPPs. This multi-omic study identifies human bone marrow lymphoid-primed progenitors, further defining the lympho-myeloid axis in human hematopoiesis.
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Affiliation(s)
- YeEun Kim
- Immunology Graduate Program, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Ariel A Calderon
- Immunology Graduate Program, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Patricia Favaro
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - David R Glass
- Immunology Graduate Program, Stanford University, Stanford, CA, USA
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Albert G Tsai
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Daniel Ho
- Department of Pathology, Stanford University, Stanford, CA, USA
| | - Luciene Borges
- Department of Pathology, Stanford University, Stanford, CA, USA
| | | | - Sean C Bendall
- Department of Pathology, Stanford University, Stanford, CA, USA.
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2
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Sigvardsson M. Molecular Regulation of Differentiation in Early B-Lymphocyte Development. Int J Mol Sci 2018; 19:ijms19071928. [PMID: 29966360 PMCID: PMC6073616 DOI: 10.3390/ijms19071928] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 06/27/2018] [Accepted: 06/28/2018] [Indexed: 12/15/2022] Open
Abstract
B-lymphocyte differentiation is one of the best understood developmental pathways in the hematopoietic system. Our understanding of the developmental trajectories linking the multipotent hematopoietic stem cell to the mature functional B-lymphocyte is extensive as a result of efforts to identify and prospectively isolate progenitors at defined maturation stages. The identification of defined progenitor compartments has been instrumental for the resolution of the molecular features that defines given developmental stages as well as for our understanding of the mechanisms that drive the progressive maturation process. Over the last years it has become increasingly clear that the regulatory networks that control normal B-cell differentiation are targeted by mutations in human B-lineage malignancies. This generates a most interesting link between development and disease that can be explored to improve diagnosis and treatment protocols in lymphoid malignancies. The aim of this review is to provide an overview of our current understanding of molecular regulation in normal and malignant B-cell development.
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Affiliation(s)
- Mikael Sigvardsson
- Division of Molecular Hematology, Lund Stem Cell Center, Department of Laboratory Medicine, Lund University, 22184 Lund, Sweden.
- Department of Clinical and Experimental Medicine, Linköping University, SE-581 85 Linköping, Sweden.
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3
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Jensen CT, Åhsberg J, Sommarin MNE, Strid T, Somasundaram R, Okuyama K, Ungerbäck J, Kupari J, Airaksinen MS, Lang S, Bryder D, Soneji S, Karlsson G, Sigvardsson M. Dissection of progenitor compartments resolves developmental trajectories in B-lymphopoiesis. J Exp Med 2018; 215:1947-1963. [PMID: 29899037 PMCID: PMC6028518 DOI: 10.1084/jem.20171384] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 03/12/2018] [Accepted: 05/18/2018] [Indexed: 01/22/2023] Open
Abstract
Jensen et al. report the identification and characterization of novel lymphoid progenitor populations in the mouse bone marrow. The work resolves the complexity of the BLP/pre-pro–B/Fraction A compartments and provides a developmental trajectory for early B cell development. To understand the developmental trajectories in early lymphocyte differentiation, we identified differentially expressed surface markers on lineage-negative lymphoid progenitors (LPs). Single-cell polymerase chain reaction experiments allowed us to link surface marker expression to that of lineage-associated transcription factors (TFs) and identify GFRA2 and BST1 as markers of early B cells. Functional analyses in vitro and in vivo as well as single-cell gene expression analyses supported that surface expression of these proteins defined distinct subpopulations that include cells from both the classical common LPs (CLPs) and Fraction A compartments. The formation of the GFRA2-expressing stages of development depended on the TF EBF1, critical both for the activation of stage-specific target genes and modulation of the epigenetic landscape. Our data show that consecutive expression of Ly6D, GFRA2, and BST1 defines a developmental trajectory linking the CLP to the CD19+ progenitor compartment.
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Affiliation(s)
| | | | | | - Tobias Strid
- Division of Molecular Hematology, Lund University, Lund, Sweden.,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Rajesh Somasundaram
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Kazuki Okuyama
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Jonas Ungerbäck
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Jussi Kupari
- Faculty of Medicine, University of Helsinki, Helsinki, Finland
| | | | - Stefan Lang
- Division of Molecular Hematology, Lund University, Lund, Sweden
| | - David Bryder
- Division of Molecular Hematology, Lund University, Lund, Sweden
| | - Shamit Soneji
- Division of Molecular Hematology, Lund University, Lund, Sweden
| | - Göran Karlsson
- Division of Molecular Hematology, Lund University, Lund, Sweden
| | - Mikael Sigvardsson
- Division of Molecular Hematology, Lund University, Lund, Sweden .,Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
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4
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Gil VS, Bhagat G, Howell L, Zhang J, Kim CH, Stengel S, Vega F, Zelent A, Petrie K. Deregulated expression of HDAC9 in B cells promotes development of lymphoproliferative disease and lymphoma in mice. Dis Model Mech 2016; 9:1483-1495. [PMID: 27799148 PMCID: PMC5200892 DOI: 10.1242/dmm.023366] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Accepted: 10/21/2016] [Indexed: 12/11/2022] Open
Abstract
Histone deacetylase 9 (HDAC9) is expressed in B cells, and its overexpression has been observed in B-lymphoproliferative disorders, including B-cell non-Hodgkin lymphoma (B-NHL). We examined HDAC9 protein expression and copy number alterations in primary B-NHL samples, identifying high HDAC9 expression among various lymphoma entities and HDAC9 copy number gains in 50% of diffuse large B-cell lymphoma (DLBCL). To study the role of HDAC9 in lymphomagenesis, we generated a genetically engineered mouse (GEM) model that constitutively expressed an HDAC9 transgene throughout B-cell development under the control of the immunoglobulin heavy chain (IgH) enhancer (Eμ). Here, we report that the Eμ-HDAC9 GEM model develops splenic marginal zone lymphoma and lymphoproliferative disease (LPD) with progression towards aggressive DLBCL, with gene expression profiling supporting a germinal center cell origin, as is also seen in human B-NHL tumors. Analysis of Eμ-HDAC9 tumors suggested that HDAC9 might contribute to lymphomagenesis by altering pathways involved in growth and survival, as well as modulating BCL6 activity and p53 tumor suppressor function. Epigenetic modifications play an important role in the germinal center response, and deregulation of the B-cell epigenome as a consequence of mutations and other genomic aberrations are being increasingly recognized as important steps in the pathogenesis of a variety of B-cell lymphomas. A thorough mechanistic understanding of these alterations will inform the use of targeted therapies for these malignancies. These findings strongly suggest a role for HDAC9 in B-NHL and establish a novel GEM model for the study of lymphomagenesis and, potentially, preclinical testing of therapeutic approaches based on histone deacetylase inhibitors. Summary: This study demonstrates that aberrant expression of HDAC9 in B cells promotes development of lymphoproliferative disease and lymphoma through altering expression of genes involved in the cell cycle and survival, and modulating the activity of key B-lineage factors such as BCL6 and p53.
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Affiliation(s)
- Veronica S Gil
- Division of Clinical Studies, Institute of Cancer Research, London SM2 5NG, UK
| | - Govind Bhagat
- Department of Pathology & Cell Biology, Columbia University Medical Center, New York, NY 10032, USA.,Department of Pathology, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032, USA
| | - Louise Howell
- Division of Molecular Pathology, Institute of Cancer Research, London SM2 5NG, UK
| | - Jiyuan Zhang
- Department of Pathology, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, NY 10032, USA.,Institute for Cancer Genetics, Columbia University, New York, NY 10032, USA
| | - Chae H Kim
- Division of Hematopathology, Sylvester Cancer Center, University of Miami, Miami, FL 33136, USA
| | - Sven Stengel
- Division of Molecular Pathology, Institute of Cancer Research, London SM2 5NG, UK
| | - Francisco Vega
- Division of Hematopathology, Sylvester Cancer Center, University of Miami, Miami, FL 33136, USA
| | - Arthur Zelent
- Department of Medicine, Sylvester Comprehensive Cancer Center, University of Miami, Miami, FL 33136, USA
| | - Kevin Petrie
- Department of Biological and Environmental Sciences, Faculty of Natural Sciences, University of Stirling, Stirling FK9 4LA, UK
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5
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Jensen CT, Lang S, Somasundaram R, Soneji S, Sigvardsson M. Identification of Stage-Specific Surface Markers in Early B Cell Development Provides Novel Tools for Identification of Progenitor Populations. THE JOURNAL OF IMMUNOLOGY 2016; 197:1937-44. [PMID: 27456481 DOI: 10.4049/jimmunol.1600297] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/18/2016] [Accepted: 06/22/2016] [Indexed: 11/19/2022]
Abstract
Whereas the characterization of B lymphoid progenitors has been facilitated by the identification of lineage- and stage-specific surface markers, the continued identification of differentially expressed proteins increases our capacity to explore normal and malignant B cell development. To identify novel surface markers with stage-specific expression patterns, we explored the reactivity of CD19(+) B cell progenitor cells to Abs targeted to 176 surface proteins. Markers with stage-specific expression were identified using a transgenic reporter gene system subdividing the B cell progenitors into four surface IgM(-) stages. This approach affirmed the utility of known stage-specific markers, as well as identifying additional proteins that selectively marked defined stages of B cell development. Among the stage-specific markers were the cell adhesion proteins CD49E, CD11A, and CD54 that are highly expressed selectively on the most immature progenitors. This work identifies a set of novel stage-specific surface markers that can be used as a complement to the classical staining protocols to explore B lymphocyte development.
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Affiliation(s)
- Christina T Jensen
- Department of Molecular Hematology, Lund University, 22184 Lund, Sweden; and
| | - Stefan Lang
- Department of Molecular Hematology, Lund University, 22184 Lund, Sweden; and
| | - Rajesh Somasundaram
- Department of Clinical and Experimental Medicine, Linköping University, 58185 Linköping, Sweden
| | - Shamit Soneji
- Department of Molecular Hematology, Lund University, 22184 Lund, Sweden; and
| | - Mikael Sigvardsson
- Department of Molecular Hematology, Lund University, 22184 Lund, Sweden; and Department of Clinical and Experimental Medicine, Linköping University, 58185 Linköping, Sweden
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6
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Tsuneto M, Tokoyoda K, Kajikhina E, Hauser AE, Hara T, Tani-Ichi S, Ikuta K, Melchers F. B-cell progenitors and precursors change their microenvironment in fetal liver during early development. Stem Cells 2015; 31:2800-12. [PMID: 23666739 DOI: 10.1002/stem.1421] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Accepted: 04/15/2013] [Indexed: 01/16/2023]
Abstract
The microenvironments, in which B lymphocytes develop in fetal liver, are largely still unknown. Among the nonhematopoietic cells, we have identified and FACS-separated two subpopulations, CD45(-) TER119(-) VCAM-1(+) cells that are either CD105(high) LYVE-1(high) or CD105(low) ALCAM(high) . Immunohistochemical analyses find three of four c-Kit(+) IL-7Rα(+) B220(low) CD19(-) SLC(-) B progenitors in contact with vascular endothelial-type LYVE-1(high) cells on embryonic day 13.5. One day later c-Kit(+) IL-7Rα(+) cells develop to CD19(- and +) , SLC-expressing, DHJH-rearranged pre/pro and pro/preB-I cells. Less than 10% are still in contact with LYVE-1(high) cells, but half of them are now in contact with mesenchymally derived ALCAM(high) liver cells. All of these ALCAM(high) cells, but not the LYVE-1(high) cells produce IL-7 and CXCL12, while both produce CXCL10. Progenitors and pro/preB-I cells are chemoattracted in vitro toward CXCL10 and 12, suggesting that lymphoid progenitors with Ig gene loci in germline configuration enter the developing fetal liver at E13.5 from vascular endothelium, attracted by CXCL10, and then migrate within a day to an ALCAM(high) liver cell microenvironment, differentiating to DHJH-rearranging, surrogate light chain-expressing pre/proB and pro/preB-I cells, attracted by CXCL10 and 12. Between E15.5 and E16.5 preB-I cells expand 10-fold in continued contact with ALCAM(high) cells and begin VH- to DHJH-rearrangements in further differentiated c-Kit(-) IL-7Rα(-) preBII cells. STEM Cells 2013;31:2800-2812.
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Affiliation(s)
- Motokazu Tsuneto
- Lymphocyte Development Group, Max Planck Institute for Infection Biology, Berlin, Germany
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7
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Separation of plasmacytoid dendritic cells from B-cell-biased lymphoid progenitor (BLP) and Pre-pro B cells using PDCA-1. PLoS One 2013; 8:e78408. [PMID: 24205225 PMCID: PMC3813560 DOI: 10.1371/journal.pone.0078408] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2013] [Accepted: 09/10/2013] [Indexed: 11/22/2022] Open
Abstract
B-cell-biased lymphoid progenitors (BLPs) and Pre-pro B cells lie at a critical juncture between B cell specification and commitment. However, both of these populations are heterogenous, which hampers investigation into the molecular changes that occur as lymphoid progenitors commit to the B cell lineage. Here, we demonstrate that there are PDCA-1+Siglec H+ plasmacytoid dendritic cells (pDCs) that co-purify with BLPs and Pre-pro B cells, which express little or no CD11c or Ly6C. Removal of PDCA-1+ pDCs separates B cell progenitors that express high levels of a Rag1-GFP reporter from Rag1-GFPlow/neg pDCs within the BLP and Pre-pro B populations. Analysis of Flt3-ligand knockout and IL-7Rα knockout mice revealed that there is a block in B cell development at the all-lymphoid progenitor (ALP) stage, as the majority of cells within the BLP or Pre-pro B gates were PDCA-1+ pDCs. Thus, removal of PDCA-1+ pDCs is critical for analysis of BLP and Pre-pro B cell populations. Analysis of B cell potential within the B220+CD19− fraction demonstrated that AA4.1+Ly6D+PDCA-1− Pre-pro B cells gave rise to CD19+ B cells at high frequency, while PDCA-1+ pDCs in this fraction did not. Interestingly, the presence of PDCA-1+ pDCs within CLPs may help to explain the conflicting results regarding the origin of these cells.
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8
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Åhsberg J, Ungerbäck J, Strid T, Welinder E, Stjernberg J, Larsson M, Qian H, Sigvardsson M. Early B-cell factor 1 regulates the expansion of B-cell progenitors in a dose-dependent manner. J Biol Chem 2013; 288:33449-61. [PMID: 24078629 DOI: 10.1074/jbc.m113.506261] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Transcription factor doses are of importance for normal and malignant B-lymphocyte development; however, the understanding of underlying mechanisms and functional consequences of reduced transcription factor levels is limited. We have analyzed progenitor and B-lineage compartments in mice carrying heterozygote mutations in the E2a, Ebf1, or Pax5 gene. Although lymphoid progenitors from Ebf1 or Pax5 heterozygote mice were specified and lineage-restricted in a manner comparable with Wt progenitors, this process was severely impaired in E2a heterozygote mutant mice. This defect was not significantly enhanced upon combined deletion of E2a with Ebf1 or Pax5. Analysis of the pre-B-cell compartment in Ebf1 heterozygote mice revealed a reduction in cell numbers. These cells expressed Pax5 and other B-lineage-associated genes, and global gene expression analysis suggested that the reduction of the pre-B-cell compartment was a result of impaired pre-B-cell expansion. This idea was supported by a reduction in IL2Rα-expressing late pre-B-cells as well as by cell cycle analysis and by the finding that the complexity of the VDJ rearrangement patterns was comparable in Wt and Ebf1(+/-) pre-B-cells, although the number of progenitors was reduced. Heterozygote deletion of Ebf1 resulted in impaired response to IL7 in vitro and reduced expression levels of pre-BCR on the cell surface, providing possible explanations for the observed stage-specific reduction in cellular expansion. Thus, transcription factor doses are critical for specification as well as expansion of B-lymphoid progenitors, providing increased insight into the molecular regulation of B-cell development.
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Affiliation(s)
- Josefine Åhsberg
- From the Department of Clinical and Experimental Medicine, Experimental Hematopoiesis Unit, Faculty for Health Sciences, Linköping University, University Lab 1, Level 13, SE-581 85 Linköping, Sweden
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9
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Single-cell analysis of early B-lymphocyte development suggests independent regulation of lineage specification and commitment in vivo. Proc Natl Acad Sci U S A 2012; 109:15871-6. [PMID: 23019372 DOI: 10.1073/pnas.1210144109] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
To better understand the process of B-lymphocyte lineage restriction, we have investigated molecular and functional properties in early B-lineage cells from Pax-5-deficient animals crossed to a B-lineage-restricted reporter mouse, allowing us to identify B-lineage-specified progenitors independently of conventional surface markers. Pax-5 deficiency resulted in a dramatic increase in the frequency of specified progenitor B-cells marked by expression of a λ5 (Igll1) promoter-controlled reporter gene. Gene expression analysis of ex vivo isolated progenitor cells revealed that Pax-5 deficiency has a minor impact on B-cell specification. However, single-cell in vitro differentiation analysis of ex vivo isolated cells revealed that specified B-lineage progenitors still displayed a high degree of plasticity for development into NK or T lineage cells. In contrast, we were unable to detect any major changes in myeloid lineage potential in specified Pax-5-deficient cells. By comparison of gene expression patterns in ex vivo isolated Pax-5- and Ebf-1-deficient progenitors, it was possible to identify a set of B-cell-restricted genes dependent on Ebf-1 but not Pax-5, supporting the idea that B-cell specification and commitment is controlled by distinct regulatory networks.
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10
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Welinder E, Ahsberg J, Sigvardsson M. B-lymphocyte commitment: identifying the point of no return. Semin Immunol 2011; 23:335-40. [PMID: 21944938 DOI: 10.1016/j.smim.2011.08.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Accepted: 08/19/2011] [Indexed: 02/07/2023]
Abstract
Even though B-lymphocyte development is one of the best understood models for cell differentiation in the hematopoetic system, recent advances in cell sorting and functional genomics has increased this understanding further. This has suggested that already early lymphoid primed multipotent progenitor cells (LMPPs) express low levels of lymphoid restricted transcripts. The expression of these genes becomes more pronounced when cells enter the FLT-3/IL-7 receptor positive common lymphoid progenitor (CLP) stage. However, the expression of B-lineage specific genes is limited to a B-cell restricted Ly6D surface positive subpopulation of the CLP compartment. The gene expression patterns also reflect differences in lineage potential and while Ly6D negative FLT-3/IL-7 receptor positive cells represents true CLPs with an ability to generate B/T and NK cells, the Ly6D positive cells lack NK cell potential and display a reduced T-cell potential in vivo. These recent findings suggest that the CLP compartment is highly heterogenous and that the point of no return in B-cell development may occur already in B220(-)CD19(-) cells. These findings have allowed for a better understanding of the interplay between transcription factors like EBF-1, PAX-5 and E47, all known as crucial for normal B-cell development. In this review, we aim to provide a comprehensive overview of B-cell fate specification and commitment based on the recent advances in the understanding of molecular networks as well as functional properties of early progenitor populations.
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Affiliation(s)
- Eva Welinder
- Lund Stem Cell Center, BMC B10, 221 84 Lund, Sweden
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11
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Abstract
Abstract
Deficiencies in the IL-7 signaling pathway result in severe disruptions of lymphoid development in adult mice. To understand more about how IL-7 deficiency impacts early lymphoid development, we have investigated lineage restriction events within the common lymphoid progenitor (CLP) compartment in IL-7 knockout mice. This revealed that although IL-7 deficiency had a minor impact on the development of LY6D− multipotent CLPs, the formation of the lineage restricted LY6D+ CLP population was dramatically reduced. This was reflected in a low-level transcription of B-lineage genes as well as in a loss of functional B-cell commitment. The few Ly6D+ CLPs developed in the absence of IL-7 displayed increased lineage plasticity and low expression of Ebf-1. Absence of Ebf-1 could be linked to increased plasticity because even though Ly6D+ cells develop in Ebf-1–deficient mice, these cells retain both natural killer and dendritic cell potential. This reveals that IL-7 is essential for normal development of Ly6D+ CLPs and that Ebf-1 is crucial for lineage restriction in early lymphoid progenitors.
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12
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Zandi S, Bryder D, Sigvardsson M. Load and lock: the molecular mechanisms of B-lymphocyte commitment. Immunol Rev 2010; 238:47-62. [DOI: 10.1111/j.1600-065x.2010.00950.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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13
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Single-cell analysis of the common lymphoid progenitor compartment reveals functional and molecular heterogeneity. Blood 2009; 115:2601-9. [PMID: 19996414 DOI: 10.1182/blood-2009-08-236398] [Citation(s) in RCA: 98] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
To investigate molecular events involved in the regulation of lymphoid lineage commitment, we crossed lambda5 reporter transgenic mice to Rag1-GFP knockin mice. This allowed us to subfractionate common lymphoid progenitors and pre-pro-B (fraction A) cells into lambda5(-)Rag1(low), lambda5(-)Rag1(high), and lambda5(+)Rag1(high) cells. Clonal in vitro differentiation analysis demonstrated that Rag1(low) cells gave rise to B/T and NK cells. Rag1(high) cells displayed reduced NK-cell potential with preserved capacity to generate B- and T-lineage cells, whereas the lambda5(+) cells were B-lineage restricted. Ebf1 and Pax5 expression was largely confined to the Rag1(high) populations. These cells also expressed a higher level of the surface protein LY6D, providing an additional tool for the analysis of early lymphoid development. These data suggest that the classic common lymphoid progenitor compartment composes a mixture of cells with relatively restricted lineage potentials, thus opening new possibilities to investigate early hematopoiesis.
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14
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Zandi S, Mansson R, Tsapogas P, Zetterblad J, Bryder D, Sigvardsson M. EBF1 is essential for B-lineage priming and establishment of a transcription factor network in common lymphoid progenitors. THE JOURNAL OF IMMUNOLOGY 2008; 181:3364-72. [PMID: 18714008 DOI: 10.4049/jimmunol.181.5.3364] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Development of B-lymphoid cells in the bone marrow is a process under strict control of a hierarchy of transcription factors. To understand the development of a B-lymphoid-restricted functional network of transcription factors, we have investigated the cell autonomous role of the transcription factor EBF1 in early B cell development. This revealed that even though transplanted EBF1-deficient fetal liver cells were able to generate common lymphoid progenitors (CLPs) as well as B220(+)CD43(+)AA4.1(+) candidate precursor B cells, none of these populations showed signs of B lineage priming. The isolated CLPs were able to generate T lymphocytes in vitro supporting the idea that the phenotype of EBF1-deficient mice is restricted to the development of the B lineage. Furthermore, EBF deficient CLPs displayed a reduction in Ig H chain recombination as compared with their wild-type counterpart and essentially lacked transcription of B-lineage-associated genes. Among the genes displaying reduced expression in the EBF1 deficient CLPs were the transcription factors Pax5, Pou2af1 (OcaB), and FoxO1 that all appear to be direct genetic targets for EBF1 because their promoters contained functional binding sites for this factor. This leads us to suggest that EBF1 regulates a transcription factor network crucial for B lineage commitment.
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Affiliation(s)
- Sasan Zandi
- Department for Biomedicin and Surgery, Linköping University, Sweden
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15
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B-lineage commitment prior to surface expression of B220 and CD19 on hematopoietic progenitor cells. Blood 2008; 112:1048-55. [DOI: 10.1182/blood-2007-11-125385] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Abstract
Commitment of hematopoietic progenitor cells to B-lymphoid cell fate has been suggested to coincide with the development of PAX5-expressing B220+CD19+ pro–B cells. We have used a transgenic reporter mouse, expressing human CD25 under the control of the B-lineage–restricted Igll1 (λ5) promoter to investigate the lineage potential of early progenitor cells in the bone marrow. This strategy allowed us to identify a reporter expressing LIN−B220−CD19−CD127+FLT3+SCA1lowKITlow population that displays a lack of myeloid and a 90% reduction in in vitro T-cell potential compared with its reporter-negative counterpart. Gene expression analysis demonstrated that these lineage-restricted cells express B-lineage–associated genes to levels comparable with that observed in pro–B cells. These data suggest that B-lineage commitment can occur before the expression of B220 and CD19.
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16
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Petropoulos K, Arseni N, Schessl C, Stadler CR, Rawat VPS, Deshpande AJ, Heilmeier B, Hiddemann W, Quintanilla-Martinez L, Bohlander SK, Feuring-Buske M, Buske C. A novel role for Lef-1, a central transcription mediator of Wnt signaling, in leukemogenesis. ACTA ACUST UNITED AC 2008; 205:515-22. [PMID: 18316418 PMCID: PMC2275375 DOI: 10.1084/jem.20071875] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Canonical Wnt signaling is critically involved in normal hematopoietic development and the self-renewal process of hematopoietic stem cells (HSCs). Deregulation of this pathway has been linked to a large variety of cancers, including different subtypes of leukemia. Lef-1 is a major transcription factor of this pathway and plays a pivotal role in lymphoid differentiation as well as in granulopoiesis. Here, we demonstrate Lef-1 expression in murine HSCs as well as its expression in human leukemia. Mice transplanted with bone marrow retrovirally transduced to express Lef-1 or a constitutive active Lef-1 mutant showed a severe disturbance of normal hematopoietic differentiation and finally developed B lymphoblastic and acute myeloid leukemia (AML). Lef-1–induced AMLs were characterized by immunoglobulin (Ig) DH-JH rearrangements and a promiscuous expression of lymphoid and myeloid regulatory factors. Furthermore, single cell experiments and limiting dilution transplantation assays demonstrated that Lef-1–induced AML was propagated by a leukemic stem cell with lymphoid characteristics displaying Ig DH-JH rearrangements and a B220+ myeloid marker− immunophenotype. These data indicate a thus far unknown role of Lef-1 in the biology of acute leukemia, pointing to the necessity of balanced Lef-1 expression for an ordered hematopoietic development.
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17
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Rumfelt LL, Zhou Y, Rowley BM, Shinton SA, Hardy RR. Lineage specification and plasticity in CD19- early B cell precursors. ACTA ACUST UNITED AC 2006; 203:675-87. [PMID: 16505143 PMCID: PMC2118241 DOI: 10.1084/jem.20052444] [Citation(s) in RCA: 151] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
We describe here three CD19- B cell precursor populations in mouse bone marrow identified using 12-color flow cytometry. Cell transfer experiments indicate lineage potentials consistent with multilineage progenitor (MLP), common lymphoid progenitor (CLP), and B lineage-restricted pre-pro-B (Fr. A), respectively. However, single cell in vitro assays reveal lineage plasticity: lymphoid/myeloid lineage potential for CLP and B/T lineage potential for Fr. A. Despite myeloid potential, recombination activating gene 2 reporter activation is first detected at low levels in most MLP cells, with 95% of CLPs showing 10-fold increased levels. Furthermore, single cell analysis shows that half of CLP and 90% of Fr. A cells contain heavy chain DJ rearrangements. These data, together with expression profiles of lineage-specific genes, demonstrate progressive acquisition of B lineage potential and support an asynchronous view of early B cell development, in which B lineage specification initiates in the MLP/CLP stage, whereas myeloid potential is not lost until the pre-pro-B (Fr. A) stage, and B/T lymphoid plasticity persists until the CD19+ pro-B stage. Thus, MLP, CLP, and Fr. A represent progressively B lineage-specified stages in development, before the CD19+ B lineage-committed pro-B stage.
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Affiliation(s)
- Lynn L Rumfelt
- Division of Basic Sciences, Fox Chase Cancer Center, Philadelphia, PA 19111, USA
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18
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Melchers F. The pre-B-cell receptor: selector of fitting immunoglobulin heavy chains for the B-cell repertoire. Nat Rev Immunol 2005; 5:578-84. [PMID: 15999097 DOI: 10.1038/nri1649] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
In this Opinion article, I address the role of the pre-B-cell receptor (pre-BCR) in the development of antigen-specific B cells in terms of immunoglobulin heavy chain (IgH) variable-region repertoire selection, precursor B-cell differentiation and proliferation, and IgH allelic exclusion. Comparisons with the role of the pre-T-cell receptor (pre-TCR) in T-cell development raise provocative questions. Why do B- and T-cell lineages both use a surrogate chain - the surrogate light chain and the pre-TCR alpha-chain, respectively - as a step to develop their repertoires of antigen-recognizing cells? What are the functions of the pre-BCR and pre-TCR in lymphocyte differentiation and antigen-receptor allelic exclusion? This article, together with the accompanying article by Harald von Boehmer, hopes to answer some of these questions.
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Affiliation(s)
- Fritz Melchers
- Max Planck Institute for Infection Biology, Campus Charité Mitte, Schumannstrasse 21-22, D-10117 Berlin, Germany.
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19
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Galler GR, Mundt C, Parker M, Pelanda R, Mårtensson IL, Winkler TH. Surface mu heavy chain signals down-regulation of the V(D)J-recombinase machinery in the absence of surrogate light chain components. ACTA ACUST UNITED AC 2004; 199:1523-32. [PMID: 15173209 PMCID: PMC2211789 DOI: 10.1084/jem.20031523] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Early B cell development is characterized by stepwise, ordered rearrangement of the immunoglobulin (Ig) heavy (HC) and light (LC) chain genes. Only one of the two alleles of these genes is used to produce a receptor, a phenomenon referred to as allelic exclusion. It has been suggested that pre–B cell receptor (pre-BCR) signals are responsible for down-regulation of the VDJH-recombinase machinery (Rag1, Rag2, and terminal deoxynucleotidyl transferase [TdT]), thereby preventing further rearrangement on the second HC allele. Using a mouse model, we show that expression of an inducible μHC transgene in Rag2−/− pro–B cells induces down-regulation of the following: (a) TdT protein, (b) a transgenic green fluorescent protein reporter reflecting endogenous Rag2 expression, and (c) Rag1 primary transcripts. Similar effects were also observed in the absence of surrogate LC (SLC) components, but not in the absence of the signaling subunit Ig-α. Furthermore, in wild-type mice and in mice lacking either λ5, VpreB1/2, or the entire SLC, the TdT protein is down-regulated in μHC+LC− pre–B cells. Surprisingly, μHC without LC is expressed on the surface of pro–/pre–B cells from λ5−/−, VpreB1−/−VpreB2−/−, and SLC−/− mice. Thus, SLC or LC is not required for μHC cell surface expression and signaling in these cells. Therefore, these findings offer an explanation for the occurrence of HC allelic exclusion in mice lacking SLC components.
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Affiliation(s)
- Gunther R Galler
- Hematopoiesis Unit, Nikolaus-Fiebiger-Center, Friedrich-Alexander University, Glueckstrasse 6, 91054 Erlangen, Germany
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20
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Gaunt SJ, Drage D, Cockley A. Vertebrate caudal gene expression gradients investigated by use of chick cdx-A/lacZ and mouse cdx-1/lacZ reporters in transgenic mouse embryos: evidence for an intron enhancer. Mech Dev 2003; 120:573-86. [PMID: 12782274 DOI: 10.1016/s0925-4773(03)00023-6] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The vertebrate caudal proteins, being upstream regulators of the Hox genes, play a role in establishment of the body plan. We describe analysis of two orthologous caudal genes (chick cdx-A and mouse cdx-1) by use of lacZ reporters expressed in transgenic mouse embryos. The expression patterns show many similarities to the expression of endogenous mouse cdx-1. At 8.7 days, cdx/lacZ activity within neurectoderm and mesoderm forms posterior-to-anterior gradients, and we discuss the possibility that similar gradients of cdx gene expression may function as morphogen gradients for the establishment of Hox gene expression boundaries. Our observations suggest that gradients form by decay of cdx/lacZ activity in cells that have moved anterior to the vicinity of the node. The cdx-A/lacZ expression pattern requires an intron enhancer that includes two functional control elements: a DR2-type retinoic acid response element and a Tcf/beta-catenin binding motif. These motifs are structurally conserved in mouse cdx-1.
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Affiliation(s)
- Stephen J Gaunt
- Department of Development and Genetics, The Babraham Institute, Babraham, Cambridge CB2 4AT, UK.
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21
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Zeisig BB, García-Cuéllar MP, Winkler TH, Slany RK. The oncoprotein MLL-ENL disturbs hematopoietic lineage determination and transforms a biphenotypic lymphoid/myeloid cell. Oncogene 2003; 22:1629-37. [PMID: 12642866 DOI: 10.1038/sj.onc.1206104] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Mixed-lineage leukemia (MLL) fusion proteins are associated with a unique class of leukemia that is characterized by the simultaneous expression of lymphoid-specific as well as myeloid-specific genes. Here we report the first experimental model of MLL. Murine bone marrow cells were retrovirally transduced to express the MLL-eleven nineteen leukemia (MLL-ENL) fusion protein. When cultivated in flt-3 ligand, stem cell factor and interleukin-7 (IL-7) in a stroma-free culture system MLL-ENL-transduced as well as control cells showed a wave of B-lymphopoiesis. Whereas the controls exhausted their proliferative capacity in a CD19+/B220+ state, a continuously proliferating CD19-/B220+ cell population emerged in the MLL-ENL-transduced cultures. Despite the lymphoid surface marker, these cells were of monocytoid morphology. The immortalized cells contained unrearranged retrovirus, expressed MLL-ENL mRNA and were able to grow in syngenic recipients. From the diseased animals an MLL-ENL positive, B220+/CD19- cell type could be reisolated and cultivated in vitro. In analogy to human MLL, MLL-ENL-transformed cells not only coexpressed lymphocyte-specific (rag1, rag2, pax5, Tdt) and monocyte-specific genes (lysozyme, c-fms), but also showed rearrangements of the genomic immunoglobulin locus. This model shows that MLL-ENL influences events of early lineage determination and it will enable the investigation of the underlying molecular processes.
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Affiliation(s)
- B B Zeisig
- Department of Genetics, University of Erlangen, Germany
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22
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Gounari F, Aifantis I, Martin C, Fehling HJ, Hoeflinger S, Leder P, von Boehmer H, Reizis B. Tracing lymphopoiesis with the aid of a pTalpha-controlled reporter gene. Nat Immunol 2002; 3:489-96. [PMID: 11927910 DOI: 10.1038/ni778] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A transgenic reporter mouse strain, which expressed the human CD25 (hCD25) surface marker as a reporter under the control of the pre-T cell receptor alpha(pTalpha) promoter, was used to identify lymphoid precursors that expressed pTalpha intracellularly. The hCD25 reporter marked intra- and extrathymic precursors of lymphocytes but not myeloid cells. The earliest intrathymic precursors were CD4(lo)CD8(-)CD25(-)CD44(+)c-Kit(+) cells that expressed elevated levels of Notch-1 mRNA. Clonogenic assays showed that the extrathymic precursors were common lymphoid progenitors (CLPs) that included CD19(-), B220(+), Thy1(+) and CD4(+) cells. Thus, the pTalpha reporter can be used to trace lymphopoiesis between CLPs and alphabeta T cells. The slower extinction of the hCD25 reporter compared to pTalpha enabled us to define points at which pTalpha(-) lineages branched off.
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MESH Headings
- Animals
- Flow Cytometry
- Gene Expression Regulation
- Hematopoiesis/immunology
- Humans
- Lymphocytes/cytology
- Lymphocytes/immunology
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/immunology
- Membrane Proteins/analysis
- Membrane Proteins/genetics
- Membrane Proteins/immunology
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Phenotype
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
- Receptor, Notch1
- Receptors, Antigen, T-Cell, alpha-beta
- Receptors, Cell Surface
- Receptors, Interleukin-2/immunology
- Reverse Transcriptase Polymerase Chain Reaction
- Stem Cells
- Transcription Factors
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Affiliation(s)
- Fotini Gounari
- Department of Pathology, Harvard Medical School, Dana-Farber Cancer Institute, Boston, MA 02115, USA
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23
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Abstract
Surrogate light chain expression during B lineage differentiation was examined by using indicator fluorochrome-filled liposomes in an enhanced immunofluorescence assay. Pro-B cells bearing surrogate light chain components were found in mice, but not in humans. A limited subpopulation of relatively large pre-B cells in both species expressed pre-B cell receptors. These cells had reduced expression of the recombinase activating genes, RAG-1 and RAG-2. Their receptor-negative pre-B cell progeny were relatively small, expressed RAG-1 and RAG-2, and exhibited selective down-regulation of VpreB and λ5expression. Comparative analysis of the 2 pre-B cell subpopulations indicated that loss of the pre-B cell receptors from surrogate light chain gene silencing was linked with exit from the cell cycle and light chain gene rearrangement to achieve B-cell differentiation.
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24
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Uehara S, Grinberg A, Farber JM, Love PE. A role for CCR9 in T lymphocyte development and migration. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:2811-9. [PMID: 11884450 DOI: 10.4049/jimmunol.168.6.2811] [Citation(s) in RCA: 248] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
CCR9 mediates chemotaxis in response to CCL25/thymus-expressed chemokine and is selectively expressed on T cells in the thymus and small intestine. To investigate the role of CCR9 in T cell development, the CCR9 gene was disrupted by homologous recombination. B cell development, thymic alphabeta-T cell development, and thymocyte selection appeared unimpaired in adult CCR9-deficient (CCR9(-/-)) mice. However, competitive transplantation experiments revealed that bone marrow from CCR9(-/-) mice was less efficient at repopulating the thymus of lethally irradiated Rag-1(-/-) mice than bone marrow from littermate CCR9(+/+) mice. CCR9(-/-) mice had increased numbers of peripheral gammadelta-T cells but reduced numbers of gammadeltaTCR(+) and CD8alphabeta(+)alphabetaTCR(+) intraepithelial lymphocytes in the small intestine. Thus, CCR9 plays an important, although not indispensable, role in regulating the development and/or migration of both alphabeta(-) and gammadelta(-) T lymphocytes.
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MESH Headings
- Aging/genetics
- Aging/immunology
- Animals
- B-Lymphocyte Subsets/cytology
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Bone Marrow Cells/pathology
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cells, Cultured
- Chemotaxis, Leukocyte/genetics
- Chemotaxis, Leukocyte/immunology
- Crosses, Genetic
- Hematopoiesis/immunology
- Intestinal Mucosa/immunology
- Intestinal Mucosa/metabolism
- Lymph Nodes/cytology
- Lymph Nodes/immunology
- Lymph Nodes/metabolism
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Organ Specificity/genetics
- Organ Specificity/immunology
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, gamma-delta/biosynthesis
- Receptors, CCR
- Receptors, Chemokine/biosynthesis
- Receptors, Chemokine/deficiency
- Receptors, Chemokine/genetics
- Receptors, Chemokine/physiology
- Spleen/cytology
- Spleen/immunology
- Spleen/metabolism
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
- T-Lymphocyte Subsets/pathology
- Thymus Gland/immunology
- Thymus Gland/pathology
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Affiliation(s)
- Shoji Uehara
- Laboratory of Mammalian Genes and Development, National Institute of Child Health and Human Development, and Laboratory of Clinical Investigation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892
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25
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Petersson K, Mårtensson A, Mertsching E, Winkler T, Ceredig R, Mårtensson IL, Ivars F. A pTalpha-negative subpopulation of CD25+ TN thymocytes revealed by a transgenic marker. Scand J Immunol 2002; 55:119-28. [PMID: 11896928 DOI: 10.1046/j.1365-3083.2002.01022.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
We have recently generated 5'lambda5-huTAC mice, which express the human CD25 (huTAC) gene under the control of the 5'-flanking region of the mouse lambda5-gene. The huTAC-transgene was expressed in pre-B cells but neither in mature B cells nor in T cells of these mice. In this report we demonstrate that the transgene is also transiently expressed by adult CD25+ CD3-CD4-CD8- (triple negative, TN) thymocytes and in fetal thymocytes. The huTAC+, in contrast to the huTAC- subpopulation of the CD44+CD25+ TN cells, was unexpectedly found not to express the pTalpha-gene. Still the huTAC+CD44+CD25+ TN cells reconstituted the development of both alphabeta and gammadelta lineage cells equally efficiently as the pTalpha-expressing huTAC- fraction, demonstrating that this pTalpha-negative subpopulation contained precursors for both T-cell lineages. Single cell reverse transcription-polymerase chain reaction (RT-PCR) experiments demonstrated that also in normal mice only a fraction of CD44+CD25+ and CD44-CD25+ TN cells expressed this gene. Taken together, these data indicate that huTAC transgene expression revealed a truly pTalpha-negative fraction of the CD44+CD25+ TN cells. The observation that not all precursors in the CD25+ TN population express the pTalpha-gene has important implications for the understanding of early T-cell development and T-cell lineage commitment.
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MESH Headings
- Animals
- B-Lymphocytes/immunology
- Fetus/cytology
- Fetus/immunology
- Gene Expression
- Genes, Reporter
- Genetic Markers
- Hematopoietic Stem Cells/immunology
- Hyaluronan Receptors/metabolism
- Liver/cytology
- Liver/immunology
- Membrane Glycoproteins/genetics
- Mice
- Mice, Inbred C57BL
- Mice, Transgenic
- Receptors, Antigen, T-Cell, alpha-beta/metabolism
- Receptors, Antigen, T-Cell, gamma-delta/metabolism
- Receptors, Interleukin-2/genetics
- Receptors, Interleukin-2/metabolism
- T-Lymphocyte Subsets/immunology
- Thymus Gland/cytology
- Thymus Gland/immunology
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Affiliation(s)
- K Petersson
- Section for Immunology, Department of Cell and Molecular Biology, Lund University, Sweden
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26
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Mårtensson A, Xie XQ, Persson C, Holm M, Grundström T, Mårtensson IL. PEBP2 and c-myb sites crucial for lambda5 core enhancer activity in pre-B cells. Eur J Immunol 2001; 31:3165-74. [PMID: 11745333 DOI: 10.1002/1521-4141(200111)31:11<3165::aid-immu3165>3.0.co;2-n] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The lambda5 gene is expressed exclusively in precursor (pre-) B cells where its gene product, as part of the pre-B cell receptor, is crucial for the proliferation of these cells. Several DNA regions regulate the activity and expression pattern of the lambda5 gene. Amongst these is an enhancer, B(lambda5), located 5' of the gene. Here we analyze the lambda5 enhancer core, b(lambda5), which in earlier experiments was demonstrated to retain 50% of the enhancer activity, and show that this activity is restricted to pre-B cells. We identify a DNA element within b(lambda5), PEBP2(lambda5), which is essential for enhancer activity: mutation within this site dramatically reduces core enhancer activity in pre-B cells. The PEBP2(lambda5) site binds bacterially produced polyoma enhancer binding proteins (PEBP) (Runx/AML/CBFA). Furthermore, PEBP2 proteins present in nuclear extracts from murine pre-B cells bind to the PEBP2(lambda5) element. PEBP2 proteins in mature B cells also bind to the PEBP2(lambda5 )element, implying that if PEBP2 proteins are responsible for the stage-specific expression, they have to be non-activating or inhibiting in mature B cells. We also demonstrate that a described partner of PEBP2, c-myb, binds to a sequence termed myb(lambda5) located just upstream of the PEBP2(lambda5) site in the core enhancer. The myb(lambda5) element is also crucial for enhancer activity, since mutating the myb site reduces core enhancer activity to the same extent as mutating the PEBP2 site. Earlier reports have shown that c-myb is expressed at high levels in pre-B cell lines whereas its expression is down-regulated in more mature B cell lines. Thus, c-myb may be involved in determining the stage-specific expression of the lambda5 gene.
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Affiliation(s)
- A Mårtensson
- Department of Cell- and Molecular Biology, Lund University, Lund, Sweden
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27
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Wrammert J, Vingsbo Lundberg C, Leanderson T. A transgenic marker expressed on discrete populations during B-cell development. Scand J Immunol 2001; 54:357-65. [PMID: 11555402 DOI: 10.1046/j.1365-3083.2001.00968.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We describe a transgenic mouse strain that selectively express a surface marker (huCD25) on transitional B cells, pre-B cells and a lineage unidentified bone marrow (BM) population. We show that a subpopulation of B cells in Peyer's patches, spleen, blood and BM expressed the transgenic huCD25 marker on the cell surface. In the spleen, the huCD25 expression was found on transitional B cells, that had not yet been recruited into the recirculating pool. In the BM a fraction of the B220low surface immunoglobulin (Ig) negative PB493+ pre-B cells were huCD25+. HuCD25 expression was also seen on practically all immature B cells while the mature recirculating B cells did not express huCD25. A huCD25+B220- cell population was also found in the BM that had not rearranged the Ig heavy chain locus and did not express the lineage markers CD3, T-cell receptor (TCR), CD19 and Mac-1. A low expression of CD4 on these cells may indicate that they represent a noncommitted, hematopoetic progenitor cell population.
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Affiliation(s)
- J Wrammert
- Section for Immunology, Department of Cell and Molecular Biology, Lund University, Lund, Sweden.
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28
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Stephan RP, Elgavish E, Karasuyama H, Kubagawa H, Cooper MD. Analysis of VpreB expression during B lineage differentiation in lambda5-deficient mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:3734-9. [PMID: 11564789 DOI: 10.4049/jimmunol.167.7.3734] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
The VpreB/lambda5 surrogate L chain complex is an essential component of the pre-B cell receptor, the expression of which serves as an important checkpoint in B cell development. Surrogate L chains also may serve as components of murine pro-B cell receptors whose function is unknown. We have produced two new mAbs, R3 and R5, that recognize a different VpreB epitope than the one recognized by the previously described VP245 anti-mouse VpreB Ab. These Abs were used to confirm the expression of surrogate L chains on wild-type pro-B and pre-B cell lines. Although undetectable on the cell surface, VpreB was found to be normally expressed within B lineage cells of lambda5-deficient mice. Nevertheless, VpreB expression was extinguished at the B cell stage of differentiation in these mice. The normal pattern of VpreB expression in lambda5-deficient mice excludes an essential role for pro-B and pre-B cell receptors in VpreB regulation.
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Affiliation(s)
- R P Stephan
- Division of Developmental and Clinical Immunology, University of Alabama, 18214 Sixth Avenue South, Birmingham, AL 35294, USA
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29
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Reizis B, Leder P. The upstream enhancer is necessary and sufficient for the expression of the pre-T cell receptor alpha gene in immature T lymphocytes. J Exp Med 2001; 194:979-90. [PMID: 11581319 PMCID: PMC2193489 DOI: 10.1084/jem.194.7.979] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
The expression of the pre-T cell receptor alpha (pTa) gene occurs exclusively in immature T lymphocytes and is regulated by poorly defined mechanisms. We have analyzed the role of the upstream enhancer in pTa expression using conventional and bacterial artificial chromosome (BAC) reporter transgenes. The deletion of the enhancer completely abolished the expression of pTa BAC reporter in transgenic mice. Conversely, the combination of pTa enhancer and promoter targeted transgenes specifically to immature thymocytes, recapitulating the expression pattern of pTa. The core enhancer is conserved between mice and humans and contains a critical binding site for the transcription factor c-Myb. We also show that pTa promoter contains a conserved tandem E box site activated by E protein, HEB. These data establish the enhancer as a critical element regulating pTa gene expression and identify additional targets for c-Myb and E proteins in T cell development.
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MESH Headings
- Animals
- Base Sequence
- Chromosomes, Artificial, Bacterial
- Conserved Sequence
- Enhancer Elements, Genetic
- Gene Expression Regulation
- Genes, T-Cell Receptor alpha
- Hematopoietic Stem Cells/immunology
- Humans
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/genetics
- Mice
- Promoter Regions, Genetic
- Receptors, Antigen, T-Cell, alpha-beta/biosynthesis
- Receptors, Antigen, T-Cell, alpha-beta/genetics
- Sequence Homology, Nucleic Acid
- T-Lymphocytes/immunology
- Transgenes
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Affiliation(s)
- Boris Reizis
- Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115
| | - Philip Leder
- Department of Genetics and Howard Hughes Medical Institute, Harvard Medical School, Boston, MA 02115
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30
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Mundt C, Licence S, Shimizu T, Melchers F, Mårtensson IL. Loss of precursor B cell expansion but not allelic exclusion in VpreB1/VpreB2 double-deficient mice. J Exp Med 2001; 193:435-45. [PMID: 11181696 PMCID: PMC2195903 DOI: 10.1084/jem.193.4.435] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The pre-B cell receptor consists of immunoglobulin (Ig) mu heavy chains and surrogate light chain, i.e., the VpreB and lambda5 proteins. To analyze the role of the two VpreB proteins, mice lacking the VpreB1 and VpreB2 genes were generated. VpreB1(-/-) VpreB2(-/-) mice were impaired in their B cell development at the transition from pre-BI to large pre-BII cells. Pre-BII cells did not expand by proliferation, consequently 40-fold less small pre-BII and immature B cells were found in bone marrow, and the generation of immature and mature conventional B cells in spleen appeared reduced. In addition, only low numbers of B-1a cells were detected in the peritoneum. Surprisingly, Ig heavy chain allelic exclusion was still active, apparently ruling out a signaling role of a VpreB1/VpreB2-containing receptor in this process.
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Affiliation(s)
- Cornelia Mundt
- Developmental Immunology, The Babraham Institute, Cambridge CB2 4AT, United Kingdom
| | - Steve Licence
- Developmental Immunology, The Babraham Institute, Cambridge CB2 4AT, United Kingdom
| | | | | | - Inga-Lill Mårtensson
- Developmental Immunology, The Babraham Institute, Cambridge CB2 4AT, United Kingdom
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31
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Mårtensson IL, Ceredig R. Review article: role of the surrogate light chain and the pre-B-cell receptor in mouse B-cell development. Immunology 2000; 101:435-41. [PMID: 11122446 PMCID: PMC2327112 DOI: 10.1046/j.1365-2567.2000.00151.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
- I L Mårtensson
- Developmental Immunology, The Babraham Institute, Babraham, Cambridge, UK
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32
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Donohoe ME, Beck-Engeser GB, Lonberg N, Karasuyama H, Riley RL, Jäck HM, Blomberg BB. Transgenic human lambda 5 rescues the murine lambda 5 nullizygous phenotype. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:5269-76. [PMID: 10799888 DOI: 10.4049/jimmunol.164.10.5269] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The human lambda 5 (hu lambda 5) gene is the structural homologue of the murine lambda 5 (m lambda 5) gene and is transcriptionally active in pro-B and pre-B lymphocytes. The lambda 5 and VpreB polypeptides together with the Ig mu H chain and the signal-transducing subunits, Ig alpha and Ig beta, comprise the pre-B cell receptor. To further investigate the pro-B/pre-B-specific transcription regulation of hu lambda 5 in an in vivo model, we generated mouse lines that contain a 28-kb genomic fragment encompassing the entire hu lambda 5 gene. High levels of expression of the transgenic hu lambda 5 gene were detected in bone marrow pro-B and pre-B cells at the mRNA and protein levels, suggesting that the 28-kb transgene fragment contains all the transcriptional elements necessary for the stage-specific B progenitor expression of hu lambda 5. Flow cytometric and immunoprecipitation analyses of bone marrow cells and Abelson murine leukemia virus-transformed pre-B cell lines revealed the hu lambda 5 polypeptide on the cell surface and in association with mouse Ig mu and mouse VpreB. Finally, we found that the hu lambda 5 transgene is able to rescue the pre-B lymphocyte block when bred onto the m lambda 5-/- background. Therefore, we conclude that the hu lambda 5 polypeptide can biochemically and functionally substitute for m lambda 5 in vivo in pre-B lymphocyte differentiation and proliferation. These studies on the mouse and human pre-B cell receptor provide a model system to investigate some of the molecular requirements necessary for B cell development.
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MESH Headings
- Abelson murine leukemia virus/genetics
- Animals
- B-Lymphocyte Subsets/cytology
- B-Lymphocyte Subsets/immunology
- B-Lymphocyte Subsets/metabolism
- Binding Sites, Antibody/genetics
- Bone Marrow Cells/immunology
- Bone Marrow Cells/metabolism
- Cell Differentiation/genetics
- Cell Differentiation/immunology
- Cell Lineage/genetics
- Cell Lineage/immunology
- Crosses, Genetic
- Female
- Gene Expression Regulation/immunology
- Humans
- Immunoglobulin Heavy Chains/metabolism
- Immunoglobulin Light Chains
- Immunoglobulin Light Chains, Surrogate
- Immunoglobulin lambda-Chains/biosynthesis
- Immunoglobulin lambda-Chains/genetics
- Immunoglobulin lambda-Chains/metabolism
- Immunoglobulin mu-Chains/metabolism
- Immunophenotyping
- Male
- Membrane Glycoproteins/biosynthesis
- Membrane Glycoproteins/genetics
- Membrane Glycoproteins/metabolism
- Mice
- Mice, Transgenic
- Receptors, Antigen, B-Cell/biosynthesis
- Receptors, Antigen, B-Cell/genetics
- Receptors, Antigen, B-Cell/metabolism
- Stem Cells/cytology
- Stem Cells/immunology
- Stem Cells/metabolism
- Testis/immunology
- Testis/metabolism
- Thymus Gland/immunology
- Thymus Gland/metabolism
- Transgenes/immunology
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Affiliation(s)
- M E Donohoe
- Department of Microbiology, University of Miami School of Medicine, Miami, FL 33101, USA
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33
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Sigvardsson M. Overlapping expression of early B-cell factor and basic helix-loop-helix proteins as a mechanism to dictate B-lineage-specific activity of the lambda5 promoter. Mol Cell Biol 2000; 20:3640-54. [PMID: 10779354 PMCID: PMC85657 DOI: 10.1128/mcb.20.10.3640-3654.2000] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The basic helix-loop-helix (bHLH) transcription factors are a large group of proteins suggested to control key events in the development of B lymphocytes as well as of other cellular lineages. To examine how bHLH proteins activate a B-lineage-specific promoter, I investigated the ability of E47, E12, Heb, E2-2, and MyoD to activate the lambda5 surrogate light chain promoter. Comparison of the functional capacity of the E2A-encoded E47 and E12 proteins indicated that even though both were able to activate the lambda5 promoter and act in synergy with early B-cell factor (EBF), E47 displayed a higher functional activity than E12. An ability to act in synergy with EBF was also observed for Heb, E2-2, and MyoD, suggesting that these factors were functionally redundant in this regard. Mapping of functional domains in EBF and E47 revealed that the dimerization and DNA binding domains mediated the synergistic activity. Electrophoretic mobility shift assay analysis using the 5' part of the lambda5 promoter revealed formation of template-dependent heteromeric complexes between EBF and E47, suggesting that the synergistic mechanism involves cooperative binding to DNA. These findings propose a unique molecular function for E47 and provide overlapping expression with EBF as a molecular mechanism to direct B-cell-specific target gene activation by bHLH proteins.
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Affiliation(s)
- M Sigvardsson
- Immunology Group, CMB, Lund University, S-223 62 Lund, Sweden.
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34
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Ogawa M, ten Boekel E, Melchers F. Identification of CD19(-)B220(+)c-Kit(+)Flt3/Flk-2(+)cells as early B lymphoid precursors before pre-B-I cells in juvenile mouse bone marrow. Int Immunol 2000; 12:313-24. [PMID: 10700466 DOI: 10.1093/intimm/12.3.313] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The combined analysis of the expression of receptor tyrosine kinases c-Kit and Flt3/Flk-2 and of the human CD25 gene expressed as a transgene under the regulation of the mouse lambda5 promoter in the bone marrow of 1-week-old mice allows us to identify three stages of B lymphocyte development before the CD19(+)c-Kit(+) pre-B-I cells. Single-cell PCR analysis of the rearrangement status of the Ig heavy chain alleles allows us to order these early stages of B cell development as follows: (i) B220(+)CD19(-)c-Kit(lo)Flt3/Flk-2(hi)lambda5(-), (ii) B220(+)CD19(-)c-Kit(lo)Flt3/Flk-2(hi)lambda5(+) and (iii) B220(+)CD19(+)c-Kit(lo)Flt3/Flk-2(lo)lambda5(+) before B220(+)CD19(+)c-Kit(lo)Flt3/Flk-2(-)lambda5(+) pre-B-I cells. All these progenitors are clonable on stromal cells in the presence of IL-7 and can differentiate to CD19(+)c-Kit(-) B-lineage cells. A combination of stem cell factor, Flt3 ligand and IL-7 was also able to support the proliferation and differentiation of the progenitors in a suspension culture. Furthermore, the analyses indicate that the onset of D(H)J(H) rearrangements precedes the expression of the lambda5 gene. These progenitor populations were characteristic of juvenile mice and could not be detected in the bone marrow of adult mice. Hence the expression pattern, and probably the function, of the receptor tyrosine kinases in early B cell differentiation appears to be different in juvenile and adult mice.
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Affiliation(s)
- M Ogawa
- Basel Institute for Immunology, 4005 Basel, Switzerland
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35
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Lymphoid-Restricted Development From Multipotent Candidate Murine Stem Cells: Distinct and Complimentary Functions of the c-kit and flt3-Ligands. Blood 1999. [DOI: 10.1182/blood.v94.11.3781.423k04_3781_3790] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The two tyrosine kinase receptors, c-kit and flt3, and their respective ligands KL and FL, have been demonstrated to play key and nonredundant roles in regulating the earliest events in hematopoiesis. However, their precise roles and potential interactions in promoting early lymphoid commitment and development remain unclear. Here we show that most if not all murine Lin−/loSca1+c-kit+ bone marrow (BM) cells generating B220+CD19+proB-cells in response to FL and interleukin-7 (IL-7) also have a myeloid potential. In contrast to FL + IL-7, KL + IL-7 could not promote proB-cell formation from Lin−/loSca1+c-kit+ cells. However, KL potently enhanced FL + IL-7–stimulated proB-cell formation, in part through enhanced recruitment of FL + IL-7–unresponsive Lin−/loSca1+c-kit+progenitors, and in part by enhancing the growth of proB-cells. The enhanced recruitment (4-fold) in response to KL occurred exclusively from the Lin−/loSca1+c-kit+flt3−long-term repopulating stem cell population, whereas KL had no effect on FL + IL-7–stimulated recruitment of Lin−/loSca1+c-kit+flt3+short-term repopulating cells. The progeny of FL + IL-7–stimulated Lin−/loSca1+c-kit+ cells lacked in vitro and in vivo myeloid potential, but efficiently reconstituted both B and T lymphopoiesis. In agreement with this FL, but not KL, efficiently induced expression of B220 and IL-7 receptor- on Lin−/loSca1+c-kit+flt3+cells. Thus, whereas KL appears crucial for recruitment of FL + IL-7–unresponsive candidate (c-kit+flt3−) murine stem cells, FL is essential and sufficient for development toward lymphoid restricted progenitors from a population of (c-kit+flt3+) multipotent short-term reconstituting progenitors.
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36
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Lymphoid-Restricted Development From Multipotent Candidate Murine Stem Cells: Distinct and Complimentary Functions of the c-kit and flt3-Ligands. Blood 1999. [DOI: 10.1182/blood.v94.11.3781] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
The two tyrosine kinase receptors, c-kit and flt3, and their respective ligands KL and FL, have been demonstrated to play key and nonredundant roles in regulating the earliest events in hematopoiesis. However, their precise roles and potential interactions in promoting early lymphoid commitment and development remain unclear. Here we show that most if not all murine Lin−/loSca1+c-kit+ bone marrow (BM) cells generating B220+CD19+proB-cells in response to FL and interleukin-7 (IL-7) also have a myeloid potential. In contrast to FL + IL-7, KL + IL-7 could not promote proB-cell formation from Lin−/loSca1+c-kit+ cells. However, KL potently enhanced FL + IL-7–stimulated proB-cell formation, in part through enhanced recruitment of FL + IL-7–unresponsive Lin−/loSca1+c-kit+progenitors, and in part by enhancing the growth of proB-cells. The enhanced recruitment (4-fold) in response to KL occurred exclusively from the Lin−/loSca1+c-kit+flt3−long-term repopulating stem cell population, whereas KL had no effect on FL + IL-7–stimulated recruitment of Lin−/loSca1+c-kit+flt3+short-term repopulating cells. The progeny of FL + IL-7–stimulated Lin−/loSca1+c-kit+ cells lacked in vitro and in vivo myeloid potential, but efficiently reconstituted both B and T lymphopoiesis. In agreement with this FL, but not KL, efficiently induced expression of B220 and IL-7 receptor- on Lin−/loSca1+c-kit+flt3+cells. Thus, whereas KL appears crucial for recruitment of FL + IL-7–unresponsive candidate (c-kit+flt3−) murine stem cells, FL is essential and sufficient for development toward lymphoid restricted progenitors from a population of (c-kit+flt3+) multipotent short-term reconstituting progenitors.
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37
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Dannaeus K, Johannisson A, Nilsson K, Jönsson JI. Flt3 ligand induces the outgrowth of Mac-1+B220+ mouse bone marrow progenitor cells restricted to macrophage differentiation that coexpress early B cell-associated genes. Exp Hematol 1999; 27:1646-54. [PMID: 10560912 DOI: 10.1016/s0301-472x(99)00106-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Flt3 ligand (FL) is an important cytokine that affects the proliferation of hematopoietic stem cells and multipotent progenitors. In addition, FL seems to be strongly involved in the differentiation of B cells and macrophages. These two cell types are derived from separate hematopoietic lineages and display distinct surface markers, for instance, the pan-B cell marker B220 (CD45R) and the myelo/monocytic marker Mac-1 (CD11b), respectively. However, reports during several years have shown that some lineage markers can be coexpressed on factor-dependent progenitor cells as well as on some malignant leukemic clones. In the present study, we describe the ability of FL to induce the development and growth of Mac-1+ progenitor cells coexpressing B220 from c-kit+Lin- mouse bone marrow cells. FL was shown to be necessary but not sufficient for the development of Mac-1(-)B220+ cells, because certain other cytokines, in particular IL-6, had to be added to the cultures. An extended characterization of the cells revealed coexpression of other early B-cell markers, i.e., CD24, CD43, and c-kit. They expressed transcripts for c-fms, the receptor for macrophage-colony stimulating factor (M-CSF), and were able to develop into macrophages at high numbers, but not to other myeloid cells. By RT-PCR analysis we could also demonstrate expression of the B-cell associated genes Pax-5, Rag-2, and TdT. In contrast, Mac-1(+)B220- cells from the same cultures did not express any of the B-cell genes, and retained a broader myeloid differentiation capacity. Despite these B-cell associated features, Mac-1(+)B220- cells could not be induced towards B-cell progenitors. Our data suggest that FL triggers the activation of some B-cell associated genes in progenitor cells predestined to macrophage differentiation.
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Affiliation(s)
- K Dannaeus
- Department of Laboratory Medicine, Lund University, University Hospital MAS, Malmö, Sweden
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38
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Loss of c-kit Accompanies B-Lineage Commitment and Acquisition of CD45R by Most Murine B-Lymphocyte Precursors. Blood 1999. [DOI: 10.1182/blood.v94.2.713] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
Using surface markers, we identified two bone marrow (BM) subsets enriched for TdT+ cells on the brink of CD45R acquisition. These two populations, Lin−c-kitLo and Lin−c-kit−, consisting of 35.4% and 7.4%, respectively, TdT+ cells, generated B-lineage cells in overnight cultures. Approximately half of the c-kitLoB-lineage precursors were bipotential, yielding myeloid and lymphoid progeny, whereas most that were c-kit− gave rise only to lymphocytes. Analysis of B-lineage progression during a finite culture period showed that the most mature precursors were concentrated in the Lin−c-kit− population. Moreover, a majority of the earliest CD45R+ pro-B cells in BM, identified as CD45R+ CD43+ BP-1−CD25− natural killer (NK)1.1−sIgM−, were also c-kit−. These c-kit− cells, like their c-kitLocounterparts, expressed TdT, proliferated in response to interleukin (IL)-7, and generated sIgM+ cells. These data suggest that TdT expression is initiated as c-kit downregulation begins in Lin− cells, with progressive loss of c-kit during B-lineage differentiation. CD45R expression is initiated during the transition from c-kitLo to c-kit− with many cells losing c-kit before acquiring CD45R. The ability to isolate highly enriched populations of viable CD45R− precursors will be instrumental in characterizing the earliest B-lineage cells.
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39
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Loss of c-kit Accompanies B-Lineage Commitment and Acquisition of CD45R by Most Murine B-Lymphocyte Precursors. Blood 1999. [DOI: 10.1182/blood.v94.2.713.414k15_713_723] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Using surface markers, we identified two bone marrow (BM) subsets enriched for TdT+ cells on the brink of CD45R acquisition. These two populations, Lin−c-kitLo and Lin−c-kit−, consisting of 35.4% and 7.4%, respectively, TdT+ cells, generated B-lineage cells in overnight cultures. Approximately half of the c-kitLoB-lineage precursors were bipotential, yielding myeloid and lymphoid progeny, whereas most that were c-kit− gave rise only to lymphocytes. Analysis of B-lineage progression during a finite culture period showed that the most mature precursors were concentrated in the Lin−c-kit− population. Moreover, a majority of the earliest CD45R+ pro-B cells in BM, identified as CD45R+ CD43+ BP-1−CD25− natural killer (NK)1.1−sIgM−, were also c-kit−. These c-kit− cells, like their c-kitLocounterparts, expressed TdT, proliferated in response to interleukin (IL)-7, and generated sIgM+ cells. These data suggest that TdT expression is initiated as c-kit downregulation begins in Lin− cells, with progressive loss of c-kit during B-lineage differentiation. CD45R expression is initiated during the transition from c-kitLo to c-kit− with many cells losing c-kit before acquiring CD45R. The ability to isolate highly enriched populations of viable CD45R− precursors will be instrumental in characterizing the earliest B-lineage cells.
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40
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Bemark M, Mårtensson A, Liberg D, Leanderson T. Spi-C, a novel Ets protein that is temporally regulated during B lymphocyte development. J Biol Chem 1999; 274:10259-67. [PMID: 10187812 DOI: 10.1074/jbc.274.15.10259] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A novel Ets protein was isolated by yeast one-hybrid screening of a cDNA library made from lipopolysaccharide-stimulated mouse splenic B cells, using the SP6 kappa promoter kappaY element as a bait. The novel Ets protein was most closely related to PU.1 and Spi-B within the DNA binding Ets domain and was therefore named Spi-C. However, Spi-C may represent a novel subgroup within the Ets protein family, as it differed significantly from Spi-B and PU.1 within helix 1 of the Ets domain. Spi-C was encoded by a single-copy gene that was mapped to chromosome 10, region C. Spi-C interacted with DNA similarly to PU.1 as judged by methylation interference, band-shift and site selection analysis, and activated transcription of a kappaY element reporter gene upon co-transfection of HeLa cells. Spi-C RNA was expressed in mature B lymphocytes and at lower levels in macrophages. Furthermore, pre-B cell and plasma cell lines were Spi-C-negative, suggesting that Spi-C might be a regulatory molecule during a specific phase of B lymphoid development.
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Affiliation(s)
- M Bemark
- Immunology Unit, Department of Cell and Molecular Biology, Lund University, P. O. Box 7031, S-220 07 Lund, Sweden
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41
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Sabbattini P, Georgiou A, Sinclair C, Dillon N. Analysis of mice with single and multiple copies of transgenes reveals a novel arrangement for the lambda5-VpreB1 locus control region. Mol Cell Biol 1999; 19:671-9. [PMID: 9858590 PMCID: PMC83924 DOI: 10.1128/mcb.19.1.671] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/1998] [Accepted: 10/19/1998] [Indexed: 12/24/2022] Open
Abstract
The murine lambda5-VpreB1 locus encodes two proteins that form part of the pre-B-cell receptor and play a key role in B-lymphocyte development. We have identified a locus control region (LCR) which is responsible for coordinate activation of both genes in pre-B cells. Analysis of mice with single and multiple copies of transgenes shows a clear difference in the expression behavior of the genes depending on the transgene copy number. While expression of both lambda5 and VpreB1 in single- and two-copy integrations requires the presence of a set of DNase I hypersensitive sites located 3' of the lambda5 gene, small fragments containing the genes have LCR activity when arranged in multiple-copy tandem arrays, indicating that additional components of the LCR are located within or close to the genes. The complete LCR is capable of driving efficient copy-dependent expression of a lambda5 gene in pre-B cells even when it is integrated into centomeric gamma-satellite DNA. The finding that activation of expression of the locus by positively acting factors is fully dominant over the silencing effect of heterochromatin has implications for models for chromatin-mediated gene silencing during B-cell development.
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Affiliation(s)
- P Sabbattini
- Gene Regulation and Chromatin Group, MRC Clinical Sciences Centre, Imperial College School of Medicine, Hammersmith Hospital, London W12 0NN, United Kingdom
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42
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Ghia P, ten Boekel E, Rolink AG, Melchers F. B-cell development: a comparison between mouse and man. IMMUNOLOGY TODAY 1998; 19:480-5. [PMID: 9785673 DOI: 10.1016/s0167-5699(98)01330-9] [Citation(s) in RCA: 94] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
A common variable immunodeficiency (CVID) patient, who carries mutations on both alleles of the gene encoding the surrogate light chain component lambda 5/14.1, shows a similar phenotype of B-cell deficiency as the lambda 5-deficient mutant mouse. As discussed here by Paolo Ghia and colleagues, this points to a remarkably similar developmental pathway of B cells in humans and mice.
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Affiliation(s)
- P Ghia
- Dana Farber Cancer Institute Boston, MA, USA
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43
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Abstract
The VpreB and lambda 5 genes encode proteins that associate non-covalently to form the so-called surrogate light (SL) chain. The SL chain complexes with the immunoglobulin heavy chain to form the pre-B cell receptor, which plays a critical role in B cell development. Expression of the murine SL genes is regulated at the level of transcription initiation. Here, we show that a VpreB1 enhancer is located within the 356 bp immediately upstream of the coding sequence. Interestingly, this region exhibits 96% identity to the upstream region of VpreB2. Deletion mapping located the enhancer to between positions -214 and -47 (+1 is the 5'-most transcription initiation site). The enhancer is tissue and differentiation stage specific, and is composed of several DNA elements that are important for its activity. We also show that a transcription factor, early B cell factor, binds to two such elements, and that at least one of these sites is involved in determining enhancer activity.
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Affiliation(s)
- C Persson
- Department of Cell and Molecular Biology, University of Lund, Sweden.
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44
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Osmond DG, Rolink A, Melchers F. Murine B lymphopoiesis: towards a unified model. IMMUNOLOGY TODAY 1998; 19:65-8. [PMID: 9509760 DOI: 10.1016/s0167-5699(97)01203-6] [Citation(s) in RCA: 128] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- D G Osmond
- Dept of Anatomy and Cell Biology, McGill University, Montreal, Canada.
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45
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Bidirectional Effect of Interleukin-10 on Early Murine B-Cell Development: Stimulation of flt3-Ligand Plus Interleukin-7–Dependent Generation of CD19− ProB Cells From Uncommitted Bone Marrow Progenitor Cells and Growth Inhibition of CD19+ ProB Cells. Blood 1997. [DOI: 10.1182/blood.v90.11.4321] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Abstract
B-cell commitment and early development from multipotent hematopoietic progenitor cells has until recently been considered to be dependent on direct interaction with stromal cells. We recently showed that the flt3 ligand (FL) has a unique ability to interact with interleukin-7 (IL-7) to directly and selectively promote B-cell development from murine bone marrow progenitor cells with a combined myeloid and lymphoid potential. Here we report that whereas IL-10 alone has no ability to stimulate growth of primitive (Lin−Sca-1+c-kit+) bone marrow progenitor cells, it potently enhances FL + IL-7–induced proliferation (sevenfold). This enhanced proliferation results from recruitment of progenitors unresponsive to FL + IL-7 alone, as well as from increased growth of individual clones, resulting in a 7,000-fold cellular expansion over 12 days. Single cell cultures and delayed addition studies suggested that the stimulatory effect of IL-10 was directly mediated on the progenitor cells. The cells generated in response to FL + IL-7 + IL-10 appeared to be almost exclusively proB cells, as shown by their expression of B220, CD24, CD43, and lack of expression of cμ, myeloid, erythroid, and T-cell surface antigens. Although IL-10 also enhanced kit ligand (KL) + IL-7–induced proliferation of Lin−Sca-1+c-kit+ progenitor cells, the resulting cells were predominantly myeloid progeny. Accordingly, FL + IL-7 + IL-10 was 100-fold more efficient in stimulating production of proB cells than KL + IL-7 + IL-10. In contrast to its ability to stimulate the earliest phase of proB cell formation and proliferation, IL-10 inhibited growth of proB cells generated in response to FL + IL-7. Analysis of CD19 expression on cells generated in FL + IL-7 + IL-10 showed that almost all cells generated under these conditions lacked expression of CD19, in contrast to cells generated in the absence of IL-10, which were predominantly CD19+. Replating of sorted CD19+ and CD19− proB cells in FL + IL-7 or FL + IL-7 + IL-10 showed that IL-10 efficiently blocked growth of CD19+, but not CD19− cells. Both CD19− and CD19+ cells expressed λ5 and VpreB , shown to be specific for B-cell progenitors. In addition, sorted CD19− cells generated CD19+ cells in response to FL + IL-7. Thus, IL-10 has a dual regulatory effect on early B-cell development from primitive murine bone marrow progenitor cells in that it enhances FL + IL-7–induced proB-cell formation and growth before acquisition of CD19 expression, whereas growth of CD19+ proB cells is inhibited.
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46
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Bidirectional Effect of Interleukin-10 on Early Murine B-Cell Development: Stimulation of flt3-Ligand Plus Interleukin-7–Dependent Generation of CD19− ProB Cells From Uncommitted Bone Marrow Progenitor Cells and Growth Inhibition of CD19+ ProB Cells. Blood 1997. [DOI: 10.1182/blood.v90.11.4321.4321_4321_4331] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
B-cell commitment and early development from multipotent hematopoietic progenitor cells has until recently been considered to be dependent on direct interaction with stromal cells. We recently showed that the flt3 ligand (FL) has a unique ability to interact with interleukin-7 (IL-7) to directly and selectively promote B-cell development from murine bone marrow progenitor cells with a combined myeloid and lymphoid potential. Here we report that whereas IL-10 alone has no ability to stimulate growth of primitive (Lin−Sca-1+c-kit+) bone marrow progenitor cells, it potently enhances FL + IL-7–induced proliferation (sevenfold). This enhanced proliferation results from recruitment of progenitors unresponsive to FL + IL-7 alone, as well as from increased growth of individual clones, resulting in a 7,000-fold cellular expansion over 12 days. Single cell cultures and delayed addition studies suggested that the stimulatory effect of IL-10 was directly mediated on the progenitor cells. The cells generated in response to FL + IL-7 + IL-10 appeared to be almost exclusively proB cells, as shown by their expression of B220, CD24, CD43, and lack of expression of cμ, myeloid, erythroid, and T-cell surface antigens. Although IL-10 also enhanced kit ligand (KL) + IL-7–induced proliferation of Lin−Sca-1+c-kit+ progenitor cells, the resulting cells were predominantly myeloid progeny. Accordingly, FL + IL-7 + IL-10 was 100-fold more efficient in stimulating production of proB cells than KL + IL-7 + IL-10. In contrast to its ability to stimulate the earliest phase of proB cell formation and proliferation, IL-10 inhibited growth of proB cells generated in response to FL + IL-7. Analysis of CD19 expression on cells generated in FL + IL-7 + IL-10 showed that almost all cells generated under these conditions lacked expression of CD19, in contrast to cells generated in the absence of IL-10, which were predominantly CD19+. Replating of sorted CD19+ and CD19− proB cells in FL + IL-7 or FL + IL-7 + IL-10 showed that IL-10 efficiently blocked growth of CD19+, but not CD19− cells. Both CD19− and CD19+ cells expressed λ5 and VpreB , shown to be specific for B-cell progenitors. In addition, sorted CD19− cells generated CD19+ cells in response to FL + IL-7. Thus, IL-10 has a dual regulatory effect on early B-cell development from primitive murine bone marrow progenitor cells in that it enhances FL + IL-7–induced proB-cell formation and growth before acquisition of CD19 expression, whereas growth of CD19+ proB cells is inhibited.
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