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Gómez Atria D, Gaudette BT, Londregan J, Kelly S, Perkey E, Allman A, Srivastava B, Koch U, Radtke F, Ludewig B, Siebel CW, Ryan RJ, Robertson TF, Burkhardt JK, Pear WS, Allman D, Maillard I. Stromal Notch ligands foster lymphopenia-driven functional plasticity and homeostatic proliferation of naïve B cells. J Clin Invest 2022; 132:158885. [PMID: 35579963 PMCID: PMC9246379 DOI: 10.1172/jci158885] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 05/12/2022] [Indexed: 11/17/2022] Open
Abstract
In lymphopenic environments, secondary lymphoid organs regulate the size of B and T-cell compartments by supporting homeostatic proliferation of mature lymphocytes. The molecular mechanisms underlying these responses and their functional consequences remain incompletely understood. To evaluate homeostasis of the mature B-cell pool during lymphopenia, we turned to an adoptive transfer model of purified follicular B-cells into Rag2-/- mouse recipients. Highly purified follicular B-cells transdifferentiated into marginal zone-like B-cells when transferred into Rag2-/- lymphopenic hosts, but not into wild-type hosts. In lymphopenic spleens, transferred B-cells gradually lost their follicular phenotype and acquired characteristics of marginal zone B-cells, as judged by cell surface phenotype, expression of integrins and chemokine receptors, positioning close to the marginal sinus, and an ability to rapidly generate functional plasma cells. Initiation of follicular to marginal zone B-cell transdifferentiation preceded proliferation. Furthermore, the transdifferentiation process was dependent on Notch2 receptors in B-cells and expression of Delta-like1 Notch ligands by splenic Ccl19-Cre+ fibroblastic stromal cells. Gene expression analysis showed rapid induction of Notch-regulated transcripts followed by upregulated Myc expression and acquisition of broad transcriptional features of marginal zone B-cells. Thus, naïve mature B-cells are endowed with plastic transdifferentiation potential in response to increased stromal Notch ligand availability during lymphopenia.
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Affiliation(s)
- Daniela Gómez Atria
- Department of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Brian T Gaudette
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Jennifer Londregan
- Immunology Graduate Group, University of Pennsylvania, Philadelphia, United States of America
| | - Samantha Kelly
- Department of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Eric Perkey
- Graduate Program in Cellular and Molecular Biology, University of Michigan, Ann Arbor, United States of America
| | - Anneka Allman
- Department of Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Bhaskar Srivastava
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Ute Koch
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Freddy Radtke
- School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | | | - Christian W Siebel
- Department of Discovery Oncology, Genentech Inc., South San Francisco, United States of America
| | - Russell Jh Ryan
- Department of Pathology, University of Michigan, Ann Arbor, United States of America
| | - Tanner F Robertson
- Immunology Graduate Group, University of Pennsylvania, Philadelphia, United States of America
| | - Janis K Burkhardt
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Warren S Pear
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - David Allman
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, United States of America
| | - Ivan Maillard
- University of Pennsylvania, Philadelphia, United States of America
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Lechner M, Engleitner T, Babushku T, Schmidt-Supprian M, Rad R, Strobl LJ, Zimber-Strobl U. Notch2-mediated plasticity between marginal zone and follicular B cells. Nat Commun 2021; 12:1111. [PMID: 33597542 PMCID: PMC7889629 DOI: 10.1038/s41467-021-21359-1] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Accepted: 01/22/2021] [Indexed: 02/07/2023] Open
Abstract
Follicular B (FoB) and marginal zone B (MZB) cells are functionally and spatially distinct mature B cell populations in the spleen, originating from a Notch2-dependent fate decision after splenic influx of immature transitional B cells. In the B cell follicle, a Notch2-signal is provided by DLL-1-expressing fibroblasts. However, it is unclear whether FoB cells, which are in close contact with these DLL-1 expressing fibroblasts, can also differentiate to MZB cells if they receive a Notch2-signal. Here, we show induced Notch2IC-expression in FoB cells re-programs mature FoB cells into bona fide MZB cells as is evident from the surface phenotype, localization, immunological function and transcriptome of these cells. Furthermore, the lineage conversion from FoB to MZB cells occurs in immunocompetent wildtype mice. These findings demonstrate plasticity between mature FoB and MZB cells that can be driven by a singular signaling event, the activation of Notch2.
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Affiliation(s)
- Markus Lechner
- Research Unit Gene Vectors, Helmholtz Zentrum München GmbH, German Research Center for Environmental Health, München, Germany
| | - Thomas Engleitner
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, München, Germany
- Institute of Molecular Oncology and Functional Genomics, TUM School of Medicine, Technical University of Munich, Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Tea Babushku
- Research Unit Gene Vectors, Helmholtz Zentrum München GmbH, German Research Center for Environmental Health, München, Germany
| | - Marc Schmidt-Supprian
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, München, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
- Institute of Experimental Hematology, TUM School of Medicine, Technical University of Munich, Munich, Germany
| | - Roland Rad
- TranslaTUM, Center for Translational Cancer Research, Technical University of Munich, München, Germany
- Institute of Molecular Oncology and Functional Genomics, TUM School of Medicine, Technical University of Munich, Munich, Germany
- German Cancer Consortium (DKTK), Heidelberg, Germany
| | - Lothar J Strobl
- Research Unit Gene Vectors, Helmholtz Zentrum München GmbH, German Research Center for Environmental Health, München, Germany
| | - Ursula Zimber-Strobl
- Research Unit Gene Vectors, Helmholtz Zentrum München GmbH, German Research Center for Environmental Health, München, Germany.
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3
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Ng HL, Taylor RL, Cheng J, Abraham LJ, Quail E, Cruickshank MN, Ulgiati D. Notch signaling induces a transcriptionally permissive state at the Complement C3d Receptor 2 (CR2) promoter in a pre-B cell model. Mol Immunol 2020; 128:150-164. [PMID: 33129017 DOI: 10.1016/j.molimm.2020.10.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 09/11/2020] [Accepted: 10/02/2020] [Indexed: 01/08/2023]
Abstract
During mammalian lymphoid development, Notch signaling is necessary at multiple stages of T lymphopoiesis, including lineage commitment, and later stages of T cell effector differentiation. In contrast, outside of a defined role in the development of splenic marginal zone B cells, there is conflicting evidence regarding whether Notch signaling plays functional roles in other B cell sub-populations. Complement receptor 2 (CR2) modulates BCR-signaling and is tightly regulated throughout differentiation. During B lymphopoiesis, CR2 is detected on immature and mature B cells with high surface expression on marginal zone B cells. Here, we have explored the possibility that Notch regulates human CR2 transcriptional activity using in vitro models including a co-culture system, co-transfection gene reporters and chromatin accessibility assays. We provide evidence that Notch signaling regulates CR2 promoter activity in a mature B cell line, as well as the induction of endogenous CR2 mRNA in a non-expressing pre-B cell line. The dynamics of endogenous gene activation suggests additional unidentified factors are required to mediate surface CR2 expression on immature and mature B lineage cells.
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Affiliation(s)
- Han Leng Ng
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia
| | - Rhonda L Taylor
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia
| | - Jessica Cheng
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia
| | - Lawrence J Abraham
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia
| | - Elizabeth Quail
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia; School of Molecular Sciences, Faculty of Science, The University of Western Australia, Australia
| | - Mark N Cruickshank
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia
| | - Daniela Ulgiati
- School of Biomedical Sciences, Faculty of Health and Medical Sciences, The University of Western Australia, Australia.
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4
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Hwang IY, Boularan C, Harrison K, Kehrl JH. Gα i Signaling Promotes Marginal Zone B Cell Development by Enabling Transitional B Cell ADAM10 Expression. Front Immunol 2018; 9:687. [PMID: 29696016 PMCID: PMC5904254 DOI: 10.3389/fimmu.2018.00687] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2017] [Accepted: 03/20/2018] [Indexed: 12/15/2022] Open
Abstract
The follicular (FO) versus marginal zone (MZ) B cell fate decision in the spleen depends upon BCR, BAFF, and Notch2 signaling. Whether or how Gi signaling affects this fate decision is unknown. Here, we show that direct contact with Notch ligand expressing stromal cells (OP9-Delta-like 1) cannot promote normal MZ B cell development when progenitor B cells lack Gαi proteins, or if Gi signaling is disabled. Consistent with faulty ADAM10-dependent Notch2 processing, Gαi-deficient transitional B cells had low ADAM10 membrane expression levels and reduced Notch2 target gene expression. Immunoblotting Gαi-deficient B cell lysates revealed a reduction in mature, processed ADAM10. Suggesting that Gαi signaling promotes ADAM10 membrane expression, stimulating normal transitional B cells with CXCL12 raised it, while inhibiting Gαi nucleotide exchange blocked its upregulation. Surprisingly, inhibiting Gαi nucleotide exchange in transitional B cells also impaired the upregulation of ADAM10 that occurs following antigen receptor crosslinking. These results indicate that Gαi signaling supports ADAM10 maturation and activity in transitional B cells, and ultimately Notch2 signaling to promote MZ B cell development.
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Affiliation(s)
- Il-Young Hwang
- B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - Cedric Boularan
- B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States.,InvivoGen, Toulouse, France
| | - Kathleen Harrison
- B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
| | - John H Kehrl
- B-Cell Molecular Immunology Section, Laboratory of Immunoregulation, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, United States
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5
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Analysis of tandem E-box motifs within human Complement receptor 2 (CR2/CD21) promoter reveals cell specific roles for RP58, E2A, USF and localized chromatin accessibility. Int J Biochem Cell Biol 2015; 64:107-19. [DOI: 10.1016/j.biocel.2015.03.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Revised: 03/03/2015] [Accepted: 03/18/2015] [Indexed: 02/06/2023]
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Obremski K, Poniatowska-Broniek G. Zearalenone induces apoptosis and inhibits proliferation in porcine ileal Peyer's patch lymphocytes. Pol J Vet Sci 2015; 18:153-61. [PMID: 25928923 DOI: 10.1515/pjvs-2015-0020] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Zearalenone (ZEN) is one of the most active natural estrogenic compounds that induces apoptosis. This study has been prompted by the widespread occurrence of ZEN in food and feed and limited knowledge about the effects of exposure to low doses of ZEN on the immune system. The aim of the study was to verify the hypothesis that low doses of ZEN contribute to induction of apoptosis and inhibition of proliferation in lymphocytes of the germinal centers (GC) of ileal Peyer's patches (IPP) in pigs. The experiment was performed on 30 female Polish Large White pigs, aged 2 months, with body weight of 15-18 kg, divided into two groups: control (C, n = 15) and experimental (Z, n = 15). On days 14, 28 and 42 of exposure to ZEN (100 μg kg(-1) feed day(-1)), apoptosis in IPP GC was evaluated histologically in HE-stained specimens, immunohistochemically by active caspase-3 staining and in mononucleosome and oligonucleosome detection-based ELISA. Proliferation was evaluated histologically by mitosis detection in HE-stained specimens, immunohistochemically by PCNA staining and in the MTT tetrazolium salt colorimetric assay detecting mitogenic responses of B cells to LPS. Exposure to low doses of ZEN for several weeks intensified apoptosis and weakened proliferation in IPP lymphocytes. ZEN influences gut-associated lymphoid tissue (GALT) by decreasing the expression of CD21+ on B cells and by increasing the percentage of B1 cell populations.
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7
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Zhao J, Giles BM, Taylor RL, Yette GA, Lough KM, Ng HL, Abraham LJ, Wu H, Kelly JA, Glenn SB, Adler AJ, Williams AH, Comeau ME, Ziegler JT, Marion M, Alarcón-Riquelme ME, Alarcón GS, Anaya JM, Bae SC, Kim D, Lee HS, Criswell LA, Freedman BI, Gilkeson GS, Guthridge JM, Jacob CO, James JA, Kamen DL, Merrill JT, Sivils KM, Niewold TB, Petri MA, Ramsey-Goldman R, Reveille JD, Scofield RH, Stevens AM, Vilá LM, Vyse TJ, Kaufman KM, Harley JB, Langefeld CD, Gaffney PM, Brown EE, Edberg JC, Kimberly RP, Ulgiati D, Tsao BP, Boackle SA. Preferential association of a functional variant in complement receptor 2 with antibodies to double-stranded DNA. Ann Rheum Dis 2014; 75:242-52. [PMID: 25180293 PMCID: PMC4717392 DOI: 10.1136/annrheumdis-2014-205584] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 08/02/2014] [Indexed: 02/03/2023]
Abstract
Objectives Systemic lupus erythematosus (SLE; OMIM 152700) is characterised by the production of antibodies to nuclear antigens. We previously identified variants in complement receptor 2 (CR2/CD21) that were associated with decreased risk of SLE. This study aimed to identify the causal variant for this association. Methods Genotyped and imputed genetic variants spanning CR2 were assessed for association with SLE in 15 750 case-control subjects from four ancestral groups. Allele-specific functional effects of associated variants were determined using quantitative real-time PCR, quantitative flow cytometry, electrophoretic mobility shift assay (EMSA) and chromatin immunoprecipitation (ChIP)-PCR. Results The strongest association signal was detected at rs1876453 in intron 1 of CR2 (pmeta=4.2×10−4, OR 0.85), specifically when subjects were stratified based on the presence of dsDNA autoantibodies (case-control pmeta=7.6×10−7, OR 0.71; case-only pmeta=1.9×10−4, OR 0.75). Although allele-specific effects on B cell CR2 mRNA or protein levels were not identified, levels of complement receptor 1 (CR1/CD35) mRNA and protein were significantly higher on B cells of subjects harbouring the minor allele (p=0.0248 and p=0.0006, respectively). The minor allele altered the formation of several DNA protein complexes by EMSA, including one containing CCCTC-binding factor (CTCF), an effect that was confirmed by ChIP-PCR. Conclusions These data suggest that rs1876453 in CR2 has long-range effects on gene regulation that decrease susceptibility to lupus. Since the minor allele at rs1876453 is preferentially associated with reduced risk of the highly specific dsDNA autoantibodies that are present in preclinical, active and severe lupus, understanding its mechanisms will have important therapeutic implications.
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Affiliation(s)
- Jian Zhao
- Division of Rheumatology, Department of Medicine, University of California at Los Angeles, Los Angeles, California, USA
| | - Brendan M Giles
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Rhonda L Taylor
- School of Pathology and Laboratory Medicine, Centre for Genetic Origins of Health and Disease, The University of Western Australia, Crawley, Western Australia, Australia
| | - Gabriel A Yette
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Kara M Lough
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Han Leng Ng
- School of Pathology and Laboratory Medicine, Centre for Genetic Origins of Health and Disease, The University of Western Australia, Crawley, Western Australia, Australia
| | - Lawrence J Abraham
- School of Pathology and Laboratory Medicine, Centre for Genetic Origins of Health and Disease, The University of Western Australia, Crawley, Western Australia, Australia
| | - Hui Wu
- Division of Rheumatology, Department of Medicine, University of California at Los Angeles, Los Angeles, California, USA
| | - Jennifer A Kelly
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Stuart B Glenn
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Adam J Adler
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Adrienne H Williams
- Department of Biostatistical Sciences and Center for Public Health Genomics, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Mary E Comeau
- Department of Biostatistical Sciences and Center for Public Health Genomics, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Julie T Ziegler
- Department of Biostatistical Sciences and Center for Public Health Genomics, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Miranda Marion
- Department of Biostatistical Sciences and Center for Public Health Genomics, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Marta E Alarcón-Riquelme
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA Pfizer-Universidad de Granada-Junta de Andalucía Center for Genomics and Oncological Research, Granada, Spain
| | | | - Graciela S Alarcón
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Juan-Manuel Anaya
- Center for Autoimmune Diseases Research (CREA), Universidad del Rosario, Bogotá, Colombia
| | - Sang-Cheol Bae
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, South Korea
| | - Dam Kim
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, South Korea
| | - Hye-Soon Lee
- Department of Rheumatology, Hanyang University Hospital for Rheumatic Diseases, Seoul, South Korea
| | - Lindsey A Criswell
- Rosalind Russell/Ephraim P. Engleman Rheumatology Research Center, University of California San Francisco, San Francisco, California, USA
| | - Barry I Freedman
- Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Gary S Gilkeson
- Division of Rheumatology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Joel M Guthridge
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Chaim O Jacob
- Department of Medicine, University of Southern California, Los Angeles, California, USA
| | - Judith A James
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Diane L Kamen
- Division of Rheumatology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Joan T Merrill
- Department of Clinical Pharmacology, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Kathy Moser Sivils
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA
| | - Timothy B Niewold
- Division of Rheumatology and Department of Immunology, Mayo Clinic, Rochester, Minnesota, USA
| | - Michelle A Petri
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Rosalind Ramsey-Goldman
- Division of Rheumatology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, USA
| | - John D Reveille
- Department of Rheumatology and Clinical Immunogenetics, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - R Hal Scofield
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, Oklahoma, USA US Department of Veterans Affairs Medical Center, Oklahoma City, Oklahoma, USA
| | - Anne M Stevens
- Division of Rheumatology, Department of Pediatrics, University of Washington, Seattle, Washington, USA Center for Immunity and Immunotherapies, Seattle Children's Research Institute, Seattle, Washington, USA
| | - Luis M Vilá
- Division of Rheumatology, Department of Medicine, University of Puerto Rico Medical Sciences Campus, San Juan, Puerto Rico
| | - Timothy J Vyse
- Division of Genetics and Molecular Medicine and Immunology, King's College London, London, UK
| | - Kenneth M Kaufman
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA US Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
| | - John B Harley
- Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA US Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
| | - Carl D Langefeld
- Department of Biostatistical Sciences and Center for Public Health Genomics, Wake Forest School of Medicine, Winston-Salem, North Carolina, USA
| | - Patrick M Gaffney
- Arthritis and Clinical Immunology Research Program, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma, USA
| | - Elizabeth E Brown
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA Department of Epidemiology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Jeffrey C Edberg
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Robert P Kimberly
- Department of Medicine, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | - Daniela Ulgiati
- School of Pathology and Laboratory Medicine, Centre for Genetic Origins of Health and Disease, The University of Western Australia, Crawley, Western Australia, Australia
| | - Betty P Tsao
- Division of Rheumatology, Department of Medicine, University of California at Los Angeles, Los Angeles, California, USA
| | - Susan A Boackle
- Division of Rheumatology, University of Colorado School of Medicine, Aurora, Colorado, USA Denver Veterans Affairs Medical Center, Denver, Colorado, USA
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Cruickshank MN, Karimi M, Mason RL, Fenwick E, Mercer T, Tsao BP, Boackle SA, Ulgiati D. Transcriptional effects of a lupus-associated polymorphism in the 5' untranslated region (UTR) of human complement receptor 2 (CR2/CD21). Mol Immunol 2012; 52:165-73. [PMID: 22673213 DOI: 10.1016/j.molimm.2012.04.013] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2012] [Revised: 04/24/2012] [Accepted: 04/29/2012] [Indexed: 11/25/2022]
Abstract
Systemic lupus erythematosus (SLE) is a complex autoimmune disease with a strong genetic component that determines risk. A common three single-nucleotide polymorphism (SNP) haplotype of the complement receptor 2 (CR2) gene has been associated with increased risk of SLE (Wu et al., 2007; Douglas et al., 2009), and a less common haplotype consisting of the major allele at SNP1 and minor alleles at SNP2 and 3 confers protection (Douglas et al., 2009). SNP1 (rs3813946), which is located in the 5' untranslated region (UTR) of the CR2 gene, altered transcriptional activity of a CR2 promoter-luciferase reporter gene construct transiently transfected into a B cell line (Wu et al., 2007) and had an independent effect in the protective haplotype (Douglas et al., 2009). In this study, we show that this SNP alters transcriptional activity in a transiently transfected non B-cell line as well as in stably transfected cell lines, supporting its relevance in vivo. Furthermore, the allele at this SNP affects chromatin accessibility of the surrounding sequence and transcription factor binding. These data confirm the effects of rs3813946 on CR2 transcription, identifying the 5' UTR to be a novel regulatory element for the CR2 gene in which variation may alter gene function and modify the development of lupus.
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Affiliation(s)
- Mark N Cruickshank
- Biochemistry and Molecular Biology, School of Chemistry and Biochemistry, The University of Western Australia, Perth, Western Australia, Australia
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9
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Gibb DR, El Shikh M, Kang DJ, Rowe WJ, El Sayed R, Cichy J, Yagita H, Tew JG, Dempsey PJ, Crawford HC, Conrad DH. ADAM10 is essential for Notch2-dependent marginal zone B cell development and CD23 cleavage in vivo. ACTA ACUST UNITED AC 2010; 207:623-35. [PMID: 20156974 PMCID: PMC2839139 DOI: 10.1084/jem.20091990] [Citation(s) in RCA: 124] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
The proteolytic activity of a disintegrin and metalloproteinase 10 (ADAM10) regulates cell-fate decisions in Drosophila and mouse embryos. However, in utero lethality of ADAM10−/− mice has prevented examination of ADAM10 cleavage events in lymphocytes. To investigate their role in B cell development, we generated B cell–specific ADAM10 knockout mice. Intriguingly, deletion of ADAM10 prevented development of the entire marginal zone B cell (MZB) lineage. Additionally, cleavage of the low affinity IgE receptor, CD23, was profoundly impaired, but subsequent experiments demonstrated that ADAM10 regulates CD23 cleavage and MZB development by independent mechanisms. Development of MZBs is dependent on Notch2 signaling, which requires proteolysis of the Notch2 receptor by a previously unidentified proteinase. Further experiments revealed that Notch2 signaling is severely impaired in ADAM10-null B cells. Thus, ADAM10 critically regulates MZB development by initiating Notch2 signaling. This study identifies ADAM10 as the in vivo CD23 sheddase and an important regulator of B cell development. Moreover, it has important implications for the treatment of numerous CD23- and Notch-mediated pathologies, ranging from allergy to cancer.
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Affiliation(s)
- David R Gibb
- Department of Microbiology and Immunology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
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10
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Deletion of putative intronic control sequences does not alter cell or stage specific expression of Cr2. Mol Immunol 2009; 47:517-25. [PMID: 19740539 DOI: 10.1016/j.molimm.2009.08.016] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2009] [Revised: 08/11/2009] [Accepted: 08/12/2009] [Indexed: 02/01/2023]
Abstract
The expression of the mouse Cr2 gene has been shown to be restricted to mature B cells, follicular dendritic cells and, in some reports, to a minor population of activated T cells. In this report, we demonstrate that the expression of antigen(s) recognized by the anti-CR2 antibody on the surface of T cells is co-incident with T cell apoptotic death. Two distinct regions of the Cr2 gene have been implicated as critical for specific expression, the promoter region at the transcription start site and a control region within the first intron of the gene, approximately 1500 bp from the transcription start site. We have created a mouse that is lacking this intronic control sequence which, in the wild type (WT) mouse, contains multiple known binding sites for RBP-jkappa, Oct, NFAT and YY1 proteins. The analysis of this mouse named Cr2iDelta (Cr2 intron deletion) demonstrated normal tissue specific expression of the Cr2 gene including a lack of expression in mouse T cells. B cell expression of the Cr2 gene products, CR1 and CR2, is normal compared to WT, and the FDC of these mice continue to express Cr2 gene products. Therefore the intronic control region of the Cr2 gene, defined in transfection-based reporter gene assays as instrumental in controlling the cell specific expression profile of Cr2, does not influence the expression of the Cr2 gene in vivo nor alter the relative production of the CR1 and CR2 proteins via alternative slicing of Cr2 gene products.
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11
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Douglas KB, Windels DC, Zhao J, Gadeliya AV, Wu H, Kaufman KM, Harley JB, Merrill J, Kimberly RP, Alarcón GS, Brown EE, Edberg JC, Ramsey-Goldman R, Petri M, Reveille JD, Vilá LM, Gaffney PM, James JA, Moser KL, Alarcón-Riquelme ME, Vyse TJ, Gilkeson GS, Jacob CO, Ziegler JT, Langefeld CD, Ulgiati D, Tsao BP, Boackle SA. Complement receptor 2 polymorphisms associated with systemic lupus erythematosus modulate alternative splicing. Genes Immun 2009; 10:457-69. [PMID: 19387458 PMCID: PMC2714407 DOI: 10.1038/gene.2009.27] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2009] [Revised: 03/17/2009] [Accepted: 03/18/2009] [Indexed: 02/05/2023]
Abstract
Genetic factors influence susceptibility to systemic lupus erythematosus (SLE). A recent family-based analysis in Caucasian and Chinese populations provided evidence for association of single-nucleotide polymorphisms (SNPs) in the complement receptor 2 (CR2/CD21) gene with SLE. Here we confirmed this result in a case-control analysis of an independent European-derived population including 2084 patients with SLE and 2853 healthy controls. A haplotype formed by the minor alleles of three CR2 SNPs (rs1048971, rs17615, rs4308977) showed significant association with decreased risk of SLE (30.4% in cases vs 32.6% in controls, P=0.016, OR=0.90 (0.82-0.98)). Two of these SNPs are in exon 10, directly 5' of an alternatively spliced exon preferentially expressed in follicular dendritic cells (FDC), and the third is in the alternatively spliced exon. Effects of these SNPs and a fourth SNP in exon 11 (rs17616) on alternative splicing were evaluated. We found that the minor alleles of these SNPs decreased splicing efficiency of exon 11 both in vitro and ex vivo. These findings further implicate CR2 in the pathogenesis of SLE and suggest that CR2 variants alter the maintenance of tolerance and autoantibody production in the secondary lymphoid tissues where B cells and FDCs interact.
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Affiliation(s)
- K B Douglas
- University of Colorado Denver School of Medicine, Aurora, CO 80045, USA
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12
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Cruickshank MN, Fenwick E, Karimi M, Abraham LJ, Ulgiati D. Cell- and stage-specific chromatin structure across the Complement receptor 2 (CR2/CD21) promoter coincide with CBF1 and C/EBP-beta binding in B cells. Mol Immunol 2009; 46:2613-22. [PMID: 19487031 DOI: 10.1016/j.molimm.2009.05.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2009] [Revised: 05/01/2009] [Accepted: 05/02/2009] [Indexed: 01/19/2023]
Abstract
Stringent developmental transcription requires multiple transcription factor (TF) binding sites, cell-specific expression of signaling molecules, TFs and co-regulators and appropriate chromatin structure. During B-lymphopoiesis, human Complement receptor 2 (CR2/CD21) is detected on immature and mature B cells but not on B cell precursors and plasma cells. We examined cell- and stage-specific human CR2 gene regulation using cell lines modeling B-lymphopoiesis. Chromatin accessibility assays revealed a region between -409 and -262 with enhanced accessibility in mature B cells and pre-B cells, compared to either non-lymphoid or plasma cell-types, however, accessibility near the transcription start site (TSS) was elevated only in CR2-expressing B cells. A correlation between histone acetylation and CR2 expression was observed, while histone H3K4 dimethylation was enriched near the TSS in both CR2-expressing B cells and non-expressing pre-B cells. Candidate sites within the CR2 promoter were identified which could regulate chromatin, including a matrix attachment region associated with CDP, SATB1/BRIGHT and CEBP-beta sites as well as two CBF1 sites. ChIP assays verified that both CBF1 and C/EBP-beta bind the CR2 promoter in B cells raising the possibility that these factors facilitate or respond to alterations in chromatin structure to control the timing and/or level of CR2 transcription.
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13
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Song R, Kim YW, Koo BK, Jeong HW, Yoon MJ, Yoon KJ, Jun DJ, Im SK, Shin J, Kong MP, Kim KT, Yoon K, Kong YY. Mind bomb 1 in the lymphopoietic niches is essential for T and marginal zone B cell development. ACTA ACUST UNITED AC 2008; 205:2525-36. [PMID: 18824586 PMCID: PMC2571928 DOI: 10.1084/jem.20081344] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Notch signaling regulates lineage decisions at multiple stages of lymphocyte development, and Notch activation requires the endocytosis of Notch ligands in the signal-sending cells. Four E3 ubiquitin ligases, Mind bomb (Mib) 1, Mib2, Neuralized (Neur) 1, and Neur2, regulate the Notch ligands to activate Notch signaling, but their roles in lymphocyte development have not been defined. We show that Mib1 regulates T and marginal zone B (MZB) cell development in the lymphopoietic niches. Inactivation of the Mib1 gene, but not the other E3 ligases, Mib2, Neur1, and Neur2, abrogated T and MZB cell development. Reciprocal bone marrow (BM) transplantation experiments revealed that Mib1 in the thymic and splenic niches is essential for T and MZB cell development. Interestingly, when BM cells from transgenic Notch reporter mice were transplanted into Mib1-null mice, the Notch signaling was abolished in the double-negative thymocytes. In addition, the endocytosis of Dll1 was impaired in the Mib1-null microenvironment. Moreover, the block in T cell development and the failure of Dll1 endocytosis were also observed in coculture system by Mib1 knockdown. Our study reveals that Mib1 is the essential E3 ligase in T and MZB cell development, through the regulation of Notch ligands in the thymic and splenic microenvironments.
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Affiliation(s)
- Ran Song
- Department of Life Science, Pohang University of Science and Technology, Pohang, Kyungbuk 790-784, South Korea
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14
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Molecular structure and expression of anthropic, ovine, and murine forms of complement receptor type 2. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2008; 15:901-10. [PMID: 18400970 DOI: 10.1128/cvi.00465-07] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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15
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Cruickshank M, Fenwick E, Abraham LJ, Ulgiati D. Quantitative differences in chromatin accessibility across regulatory regions can be directly compared in distinct cell-types. Biochem Biophys Res Commun 2007; 367:349-55. [PMID: 18164259 DOI: 10.1016/j.bbrc.2007.12.121] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2007] [Accepted: 12/19/2007] [Indexed: 11/28/2022]
Abstract
Transcriptional activation in eukaryotes is often accompanied by alterations to chromatin structure at specific regulatory sites while other genomic regions may remain unchanged. In this study, we have examined the correlation between expression and chromatin accessibility of the human CR2 gene in a panel of cell lines (U937, REH, Ramos, and Raji) using the CHART-PCR assay with the accessibility agent micrococcal nuclease (MNase). To validate the use of this assay for comparing multiple cell-types, we first tested a series of genomic regions to determine if we could observe consistent, site-specific levels of MNase chromatin accessibility. Promoter regions of the ubiquitously expressed genes GAPDH and beta-actin were similar and showed high accessibility to MNase digestion in each of the cell lines, while on the other hand, promoter regions of developmentally restricted genes PAX-7 and SP-A2 showed consistently reduced chromatin accessibility. Since CHART-PCR detected site-specific differences in chromatin accessibility in a manner that could be compared between cell-types, we next examined chromatin accessibility over the CR2 core promoter in the panel of cell lines representing either CR2 expressing or CR2 non-expressing cell-types. Our data revealed significantly enhanced accessibility over the -289 to -101 and the -115 to -12 regions of the CR2 promoter in expressing B-cells (Ramos, Raji) compared to non-expressing cells (U937, REH). Thus, CHART-PCR assays detected a correlation between chromatin accessibility and expression of the human CR2 gene, while the accessibility of other genomic regions was site-specific, but not altered between cell-types.
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Affiliation(s)
- Mark Cruickshank
- Biochemistry and Molecular Biology, School of Biomedical, Biomolecular and Chemical Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, 6009 WA, Australia
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16
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Debnath I, Roundy KM, Weis JJ, Weis JH. Defining In Vivo Transcription Factor Complexes of the Murine CD21 and CD23 Genes. THE JOURNAL OF IMMUNOLOGY 2007; 178:7139-50. [PMID: 17513763 DOI: 10.4049/jimmunol.178.11.7139] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
The expression of the CD21 and CD23 genes is coincident with differentiation from transition 1 B cells (T1) to transition 2 B cells (T2). To define constituents controlling CD21 and CD23 expression, we conducted chromatin immunoprecipitation analyses for candidate transcription factors. We found constitutive binding of Oct-1, NFAT species, YY1, NF-kappaB-p52, Pax5, E2A, and RBP-Jkappa to CD21 sequences and NF-kappaB-p52, Pax5, NFAT species, E2A, and RBP-Jkappa to CD23 promoter sequences. Splenic T and B cell subsets displayed constitutive binding of YY1, NF-kappaB-p52, Pax5, and Oct-1 proteins to CD21 sequences in B cells but no specific binding of NFATc3 or Pax5 in T cells. Similarly, CD23 sequences demonstrated constitutive binding of NF-kappaB-p52 in splenic T and B cells but only Pax5 in B cells. Of the various NFAT species, only a subset were found forming constitutive DNA/protein complexes with the CD21, CD23, and IL-2 gene sequences. Maturing B cells in the marrow possess stable Pax5 complexes on CD19, CD21, and CD23 gene promoters in the nuclei of such cells, even though only CD19 is expressed. The similarity of genetic controlling elements between the CD21 and CD23 genes does not suggest a mechanism for alternative regulation of these genes; however, separation of splenic B cell subsets into T1, T2, marginal zone (MZ), and mature follicular B cells, followed by quantitative RT-PCR, demonstrated the lack of appreciable CD23 transcripts in CD21(+) MZ cells. We propose an alternative derivation of MZ cells as maturing directly from T1 cells, leaving CD23 transcriptionally inactive in that lineage of cells.
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Affiliation(s)
- Irina Debnath
- Division of Cell Biology and Immunology, Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
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17
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Karimi M, Goldie LC, Ulgiati D, Abraham LJ. Integration site-specific transcriptional reporter gene analysis using Flp recombinase targeted cell lines. Biotechniques 2007; 42:217-24. [PMID: 17373487 DOI: 10.2144/000112317] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
While high-throughput genome-wide approaches are useful to identify important regulatory regions, traditional reporter gene methodologies still represent the ultimate steps in fine structure analysis of transcriptional control elements. However, there are still several inherent limitations in the currently available transient and stable transfection systems often leading to aberrant function of specific cis elements. In this study we overcome these problems and have developed a novel and widely applicable system that permits the comparison of transcriptional reporter gene activities following site-specific genomic integration. By using Flp recombinase-mediated integration, the system allows the integration and expression of a series of reporter gene constructs at exactly the same genomic location and orientation in all cells of any one culture. The resulting reporter gene lines carry a single reporter gene, which is incorporated within a measurably active chromatinized setting, thus more closely reflecting the endogenous gene environment.
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Affiliation(s)
- Mahdad Karimi
- University of Western Australia, Crawley, WA, Australia
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18
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Wu H, Boackle SA, Hanvivadhanakul P, Ulgiati D, Grossman JM, Lee Y, Shen N, Abraham LJ, Mercer TR, Park E, Hebert LA, Rovin BH, Birmingham DJ, Chang DM, Chen CJ, McCurdy D, Badsha HM, Thong BYH, Chng HH, Arnett FC, Wallace DJ, Yu CY, Hahn BH, Cantor RM, Tsao BP. Association of a common complement receptor 2 haplotype with increased risk of systemic lupus erythematosus. Proc Natl Acad Sci U S A 2007; 104:3961-6. [PMID: 17360460 PMCID: PMC1820691 DOI: 10.1073/pnas.0609101104] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
A genomic region on distal mouse chromosome 1 and its syntenic human counterpart 1q23-42 show strong evidence of harboring lupus susceptibility genes. We found evidence of linkage at 1q32.2 in a targeted genome scan of 1q21-43 in 126 lupus multiplex families containing 151 affected sibpairs (nonparametric linkage score 2.52, P = 0.006). A positional candidate gene at 1q32.2, complement receptor 2 (CR2), is also a candidate in the murine Sle1c lupus susceptibility locus. To explore its role in human disease, we analyzed 1,416 individuals from 258 Caucasian and 142 Chinese lupus simplex families and demonstrated that a common three-single-nucleotide polymorphism CR2 haplotype (rs3813946, rs1048971, rs17615) was associated with lupus susceptibility (P = 0.00001) with a 1.54-fold increased risk for the development of disease. Single-nucleotide polymorphism 1 (rs3813946), located in the 5' untranslated region of the CR2 gene, altered transcriptional activity, suggesting a potential mechanism by which CR2 could contribute to the development of lupus. Our findings reveal that CR2 is a likely susceptibility gene for human lupus at 1q32.2, extending previous studies suggesting that CR2 participates in the pathogenesis of systemic lupus erythematosus.
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Affiliation(s)
- Hui Wu
- Division of Rheumatology, University of California, Los Angeles, CA 90095
| | - Susan A. Boackle
- Departments of Medicine and Immunology, University of Colorado at Denver and Health Sciences Center, Denver, CO 80217
| | | | - Daniela Ulgiati
- University of Western Australia Centre for Medical Research, Western Australian Institute for Medical Research and School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley 6000 Western Australia, Australia
| | | | - Youngho Lee
- Division of Rheumatology, University of California, Los Angeles, CA 90095
| | - Nan Shen
- Department of Rheumatology, Shanghai Renji Hospital, Shanghai Second Medical University, Shanghai 200001, China
| | - Lawrence J. Abraham
- University of Western Australia Centre for Medical Research, Western Australian Institute for Medical Research and School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley 6000 Western Australia, Australia
| | - Timothy R. Mercer
- University of Western Australia Centre for Medical Research, Western Australian Institute for Medical Research and School of Biomedical, Biomolecular and Chemical Sciences, University of Western Australia, Crawley 6000 Western Australia, Australia
| | - Elly Park
- Division of Rheumatology, University of California, Los Angeles, CA 90095
| | - Lee A. Hebert
- College of Medicine and Public Health, Ohio State University, Columbus, OH 43210
| | - Brad H. Rovin
- College of Medicine and Public Health, Ohio State University, Columbus, OH 43210
| | - Dan J. Birmingham
- College of Medicine and Public Health, Ohio State University, Columbus, OH 43210
| | - Deh-Ming Chang
- Department of Internal Medicine, Tri-Service General Hospital National Defense Medical Center, Taipei 114, Taiwan
| | - Chung Jen Chen
- Division of Rheumatology, Allergy and Immunology, Chang-Gung University College of Medicine, Kwei-shan, Taiwan 333, Republic of China
| | - Deborah McCurdy
- Department of Pediatrics, University of California, Los Angeles, CA 90023
| | - Humeira M. Badsha
- Department of Rheumatology, Allergy and Immunology, Tan Tock Seng Hospital, Tan Tock Seng 308433, Republic of Singapore
| | - Bernard Y. H. Thong
- Department of Rheumatology, Allergy and Immunology, Tan Tock Seng Hospital, Tan Tock Seng 308433, Republic of Singapore
| | - Hiok H. Chng
- Department of Rheumatology, Allergy and Immunology, Tan Tock Seng Hospital, Tan Tock Seng 308433, Republic of Singapore
| | - Frank C. Arnett
- Division of Rheumatology and Clinical Immunogenetics, University of Texas Health Sciences Center, Houston, TX 77030
| | | | - C. Yung Yu
- College of Medicine and Public Health, Ohio State University, Columbus, OH 43210
| | - Bevra H. Hahn
- Division of Rheumatology, University of California, Los Angeles, CA 90095
| | - Rita M. Cantor
- Department of Pediatrics, University of California, Los Angeles, CA 90023
- Department of Human Genetics, University of California, Los Angeles, CA 90024
| | - Betty P. Tsao
- Division of Rheumatology, University of California, Los Angeles, CA 90095
- To whom correspondence should be addressed at:
University of California, Los Angeles, 1000 Veteran Avenue, Rehabilitation Center 32-59, Los Angeles, CA 90095-1670. E-mail:
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19
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Markova NG, Pinkas-Sarafova A, Simon M. A Metabolic Enzyme of the Short-Chain Dehydrogenase/Reductase Superfamily May Moonlight in the Nucleus as a Repressor of Promoter Activity. J Invest Dermatol 2006; 126:2019-31. [PMID: 16691198 DOI: 10.1038/sj.jid.5700347] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Transcriptional repression often depends on the action of recruited co-repressor complexes with intrinsic enzymatic activities. The composition of these complexes depends on the nicotine amide dinucleotide co-factors and is thus directly reflective of the metabolic state of the cells. This study provides evidence that an enzyme, hRoDH-E2, with cytoplasmic phosphorylated and reduced forms of NAD-dependent retinol dehydrogenase activity may function in the nucleus as a transcriptional repressor. By using the promoter of the epidermal late differentiation marker profilaggrin as a model, we show that both in vivo and in vitro the protein is recruited over the promoter. hRoDH-E2 represses profilaggrin promoter activity by altering the function of other activators, such as Sp1. The repressive function is associated with the ability of nuclear hRoDH-E2 to modulate the acetylation/deacetylation activity in the vicinity of transcription initiation site. These findings add hRoDH-E2 to the small group of metabolic enzymes, which, by being recruited over promoter regions, could directly link the cytoplasmic and nuclear functions within the cell.
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Affiliation(s)
- Nelli G Markova
- Living Skin Bank, Department of Oral Biology and Pathology, School of Dental Medicine, SUNY Stony Brook, New York 11794, USA.
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20
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Breous E, Wenzel A, Loos U. Promoter cloning and characterisation of the transcriptional regulation of the human thyrostimulin A2 subunit. Mol Cell Endocrinol 2005; 245:169-80. [PMID: 16376481 DOI: 10.1016/j.mce.2005.11.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/21/2005] [Revised: 11/10/2005] [Accepted: 11/11/2005] [Indexed: 11/23/2022]
Abstract
The novel heterodimeric glycoprotein hormone thyrostimulin consists of two unique subunits, A2 and B5. To understand its yet unknown transcriptional regulation, we characterised the 3.1-kb immediate 5'-flanking region of the human A2 gene localised on chromosome 11q13. In transient transfection assays this sequence exhibited promoter activity, which could be confined to nucleotides -506 to -347 relative to the ATG start codon. Interestingly, this minimal promoter appeared to be non-tissue-specific. Deletional, mutational and gel shift analyses revealed regulatory elements that are essential for the regulation of the A2 gene expression. Another noteworthy feature of this gene is the presence of silencer elements upstream and downstream of the promoter. To surmise, our results provide an initial step toward a detailed analysis of the underlying molecular mechanisms of the human thyrostimulin gene expression.
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Affiliation(s)
- Ekaterina Breous
- Department of Internal Medicine I, University of Ulm, Robert-Koch-Strasse 8, D-89081 Ulm, Germany
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21
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Sironi M, Menozzi G, Comi GP, Cagliani R, Bresolin N, Pozzoli U. Analysis of intronic conserved elements indicates that functional complexity might represent a major source of negative selection on non-coding sequences. Hum Mol Genet 2005; 14:2533-46. [PMID: 16037065 DOI: 10.1093/hmg/ddi257] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
The non-coding portion of human genome is punctuated by a large number of multispecies conserved sequence (MCS) elements with largely unknown function. We demonstrate that MCSs are unevenly distributed in human introns with the majority of relatively short introns (< 9 kb long) displaying no or a few MCSs and that MCS density reaching up to 10% of total size in longer introns. After correction for intron length, MCSs were found to be enriched within genes involved in development and transcription, whereas depleted in immune response loci. Moreover, many central nervous system tissues show a preferential expression of MCS-rich genes and MCS enrichment significantly correlates with gene functional complexity in terms of distinct protein domains. Analysis of human-mouse orthologous pairs indicated a significant association between intronic MCS density and conservation of protein sequence, promoter regions and untranslated sequences. Moreover, MCS density correlates with the predicted occurrence of human-mouse conserved alternative splicing events. These observations suggest that evolution acts on human genes as integrated units of coding and regulatory capacity and that functional complexity might represent a major source of negative selection on non-coding sequences. To substantiate our result, we also searched previously experimentally identified intronic regulatory elements and indicate that about half of these sequences map to an MCS; in particular, support to the notion whereby mutations in MCSs can result in human genetic diseases is provided, because three previously identified intronic pathological variations were found to occur within MCSs, and human disease and cancer genes were found significantly enriched in MCSs.
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Affiliation(s)
- Manuela Sironi
- Scientific Institute IRCCS E. Medea, 23842 Bosisio Parini (LC), Italy
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22
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Maier S, Santak M, Mantik A, Grabusic K, Kremmer E, Hammerschmidt W, Kempkes B. A somatic knockout of CBF1 in a human B-cell line reveals that induction of CD21 and CCR7 by EBNA-2 is strictly CBF1 dependent and that downregulation of immunoglobulin M is partially CBF1 independent. J Virol 2005; 79:8784-92. [PMID: 15994772 PMCID: PMC1168782 DOI: 10.1128/jvi.79.14.8784-8792.2005] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Accepted: 03/28/2005] [Indexed: 11/20/2022] Open
Abstract
CBF1 is a cellular highly conserved DNA binding factor that is ubiquitously expressed in all tissues and acts as a repressor of cellular genes. In Epstein-Barr virus growth-transformed B-cell lines, CBF1 serves as a central DNA adaptor molecule for several viral proteins, including the viral transactivator Epstein-Barr virus nuclear antigen 2 (EBNA-2). EBNA-2 binds to CBF1 and thereby gains access to regulatory regions of target genes and activates transcription. We have inactivated the CBF1 gene by homologous recombination in the human B-cell line DG75 and characterized changes in cellular gene expression patterns upon loss of CBF1 and activation of EBNA-2. CBF1-negative DG75 cells were viable and proliferated at wild-type rates. Loss of CBF1 was not sufficient to release repression of the previously described EBNA-2 target genes CD21 or CCR7, whereas induction of both target genes by EBNA-2 required CBF1. In contrast, repression of immunoglobulin M by EBNA-2 was mainly CBF1 independent. CBF1-negative DG75 B cells thus provide an excellent tool to dissect CBF1-dependent and -independent functions exerted by the EBNA-2 protein in future studies.
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Affiliation(s)
- Sabine Maier
- Institute of Clinical Molecular Biology, GSF National Research Center for Environment and Health, Marchioninistr. 25, D-81377 Munich, Germany
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23
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Abstract
Coregulation of lymphoid-specific gene sets is achieved by a series of epigenetic mechanisms. Association with higher-order chromosomal structures (nuclear subcompartments repressing or favouring gene expression) and locus control regions affects recombination and transcription of clonotypic antigen receptors and expression of a series of other lymphoid-specific genes. Locus control regions can regulate DNA methylation patterns in their vicinity. They may induce tissue- and site-specific DNA demethylation and affect, thereby, accessibility to recombination-activating proteins, transcription factors, and enzymes involved in histone modifications. Both DNA methylation and the Polycomb group of proteins (PcG) function as alternative systems of epigenetic memory in lymphoid cells. Complexes of PcG proteins mark their target genes by covalent histone tail modifications and influence lymphoid development and rearrangement of IgH genes. Ectopic expression of protein noncoding microRNAs may affect the generation of B-lineage cells, too, by guiding effector complexes to sites of heterochromatin assembly. Coregulation of lymphoid and viral promoters is also possible. EBNA 2, a nuclear protein encoded by episomal Epstein-Barr virus genomes, binds to the cellular protein CBF1 (C promoter binding factor 1) and operates, thereby, a regulatory network to activate latent viral promoters and cellular promoters associated with CBF1 binding sites.Key words : lymphoid cells, coregulation of gene batteries, epigenetic regulation, nuclear subcompartment switch, locus control region, DNA methylation, Polycomb group of proteins, histone modifications, microRNA, Epstein-Barr virus, EBNA 2, regulatory network.
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Affiliation(s)
- Ildikó Györy
- Microbiological Research Group, National Center for Epidemiology, Budapest, Hungary
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24
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Hu HG, Illges H, Gruss C, Knippers R. Distribution of the chromatin protein DEK distinguishes active and inactive CD21/CR2 gene in pre- and mature B lymphocytes. Int Immunol 2005; 17:789-96. [PMID: 15908448 DOI: 10.1093/intimm/dxh261] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
DEK is an abundant and ubiquitous chromatin protein that has only recently attracted attention. DEK preferentially binds to cruciform and superhelical DNA and induces positive supercoils into closed circular DNA. It is quite likely therefore that DEK performs an important architectural function in chromatin. However, it is not known how DEK is distributed in chromatin. As the first study of its kind, we investigate the distribution of DEK at the CD21/complement receptor 2 gene regulatory regions in two B lymphocyte lines, namely Ramos, which expresses the CD21 gene, and Nalm-6, which does not. We use a chromatin immunoprecipitation approach and show that DEK appears to be distributed over various regions of the expressed and silent genes, but occurs in 2- to 3-fold higher amounts at a promoter-proximal site of the expressed gene. Moreover, induction of CD21 expression in Nalm-6 cells leads to accumulation of DEK at this site. We propose that the accumulation of DEK is functionally linked to gene expression.
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Affiliation(s)
- Hong-gang Hu
- Department of Biology, University of Konstanz, D-78457 Konstanz, Germany.
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25
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Dallman MJ, Smith E, Benson RA, Lamb JR. Notch: control of lymphocyte differentiation in the periphery. Curr Opin Immunol 2005; 17:259-66. [PMID: 15886115 DOI: 10.1016/j.coi.2005.04.002] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The complexity of the Notch signalling pathway has impeded progress in understanding its precise role in differentiation processes of the mature peripheral immune system. Nevertheless, both B and T lymphocyte responses are undoubtedly influenced by Notch ligation, and defining the mechanisms by which this is achieved remains a challenge. How the innate-adaptive interface and interactions between lymphocytes can be affected, together with the potential of this pathway for therapeutic intervention remain important and stimulating issues.
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Affiliation(s)
- Margaret J Dallman
- Section of Immunology and Infection, Department of Biological Sciences, Imperial College, London, UK.
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26
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Chang H, Gwack Y, Kingston D, Souvlis J, Liang X, Means RE, Cesarman E, Hutt-Fletcher L, Jung JU. Activation of CD21 and CD23 gene expression by Kaposi's sarcoma-associated herpesvirus RTA. J Virol 2005; 79:4651-63. [PMID: 15795251 PMCID: PMC1069543 DOI: 10.1128/jvi.79.8.4651-4663.2005] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Epstein-Barr virus (EBV) EBNA2 and Kaposi's sarcoma-associated herpesvirus (KSHV) replication and transcription activator (RTA) are recruited to their responsive elements through interaction with a Notch-mediated transcription factor, RBP-Jkappa. In particular, RTA and EBNA2 interactions with RBP-Jkappa are essential for the lytic replication of KSHV and expression of B-cell activation markers CD21 and CD23a, respectively. Here, we demonstrate that like EBV EBNA2, KSHV RTA strongly induces CD21 and CD23a expression through RBP-Jkappa binding sites in the first intron of CD21 and in the CD23a core promoter, respectively. However, unlike EBV EBNA2, which alters immunoglobulin mu (Igmu) and c-myc gene expression, RTA did not affect Igmu and c-myc expression, indicating that KSHV RTA targets the Notch signal transduction pathway in a manner similar to but distinct from that of EBV EBNA2. Furthermore, RTA-induced expression of CD21 glycoprotein, which is an EBV receptor, efficiently facilitated EBV infection. In addition, RTA-induced CD23 glycoprotein underwent proteolysis and gave rise to soluble CD23 (sCD23) molecules in B lymphocytes and KSHV-infected primary effusion lymphocytes. sCD23 then stimulated primary human lymphocytes. These results demonstrate that cellular CD21 and CD23a are common targets for B lymphotropic gammaherpesviruses and that KSHV RTA regulates RBP-Jkappa-mediated cellular gene expression, which ultimately provides a favorable milieu for viral reproduction in the infected host.
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Affiliation(s)
- Heesoon Chang
- Tumor Virology Division, New England Primate Research Center, Harvard Medical School, 1 Pine Hill Dr., Southborough, MA 01772, USA
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Esparza-Gordillo J, Goicoechea de Jorge E, Buil A, Carreras Berges L, López-Trascasa M, Sánchez-Corral P, Rodríguez de Córdoba S. Predisposition to atypical hemolytic uremic syndrome involves the concurrence of different susceptibility alleles in the regulators of complement activation gene cluster in 1q32. Hum Mol Genet 2005; 14:703-12. [PMID: 15661753 DOI: 10.1093/hmg/ddi066] [Citation(s) in RCA: 218] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
The efficiency of the complement system as an innate immune defense mechanism depends on a fine control that restricts its action to pathogens and prevents non-specific damage to host tissues. Genetic and functional analyses have shown that this critical control of complement activation may be impaired in atypical hemolytic uremic syndrome (aHUS) patients. Mutations in HF1, MCP or FI have been found in aHUS patients, but incomplete penetrance of the disease in individuals carrying these mutations is relatively frequent and no genetic defect has yet been found in a majority of aHUS patients. We report here the identification of a specific SNP haplotype block, spanning the MCP gene in the regulators of complement activation gene cluster, which is over-represented in aHUS patients and strongly associates with the severity of the disease. Linkage disequilibrium analyses suggest that this SNP haplotype also includes the CR1, DAF and C4BP genes. Initial studies identified two SNPs in the haplotype that influence the transcription activity of the MCP promoter in transient transfection experiments. Notably, the SNP haplotype block was found to be particularly frequent among patients who carry mutations in HF1, MCP or FI. These findings and the identification of aHUS patients carrying mutations in two complement regulatory genes provide an important insight into the etiology of aHUS. Together, they suggest that complement regulatory molecules act as a protein network and that multiple hits, involving plasma- and membrane-associated complement regulatory proteins, are necessary to impair protection to host tissues and to confer significant predisposition to aHUS.
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Affiliation(s)
- Jorge Esparza-Gordillo
- Centro de Investigaciones Biológicas, Consejo Superior de Investigaciones Cientificas, Madrid, Spain
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28
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Boackle SA. Role of complement receptor 2 in the pathogenesis of systemic lupus erythematosus. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2005; 560:141-7. [PMID: 15932028 DOI: 10.1007/0-387-24180-9_17] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Affiliation(s)
- Susan A Boackle
- University of Colorado Health Sciences Center, Denver, Colorado 80262, USA
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29
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Holers VM. Complement receptors and the shaping of the natural antibody repertoire. ACTA ACUST UNITED AC 2004; 26:405-23. [PMID: 15614507 DOI: 10.1007/s00281-004-0186-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2004] [Accepted: 10/12/2004] [Indexed: 10/26/2022]
Abstract
Complement and complement receptors have been known for several decades to play important roles in immune effector mechanisms related to pathogen elimination and tissue inflammation. In addition, studies over the last 10 years have clearly demonstrated a key role for the complement C3d activation fragment receptor designated CR2 (complement receptor type 2) in the switched-isotype, high-affinity and memory humoral immune responses to T-dependent foreign antigens. More recent studies have extended those observations to include a key role for CR2 and C3d in the humoral immune response to T-independent foreign antigens. Conversely, as these studies have proceeded, a parallel series of analyses have linked defects in expression or function of complement C4 and other classical pathway activation pathway proteins, as well as CR2 and the closely related CR1, to the loss of self tolerance to nuclear antigens such as double-stranded DNA and chromatin in systemic lupus erythematosus. With regard to the topic of this issue, it is now becoming increasingly clear that CR2 also plays a major role in the development of the natural antibody repertoire. Specifically, in the absence of this receptor natural IgM and IgG develop in the naïve animal that demonstrate clearly altered recognition patterns for specific natural antibody targets. This repertoire change is important physiologically in at least one setting because these CR2-dependent natural antibodies are necessary for the recognition of ischemic self tissues. In addition, it is possible that certain of the phenotypes manifest by CR2-deficient mice may be strongly influenced not only by effects on later stages of B cell activation and maturation, as commonly thought, but also by alterations in the pre-existing pool of natural antibodies that are influenced by this receptor. This review will examine the evidence that has accumulated over the last few years supporting these hypotheses.
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Affiliation(s)
- V Michael Holers
- Division of Rheumatology, Department of Medicine, B-115, University of Colorado Health Sciences Center, 4200 E. 9th Avenue, Denver, CO 80262, USA.
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30
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Abstract
The complement system is comprised of a number of serum and membrane-bound proteins that play an important role in the elimination of foreign microorganisms while protecting the host organism from complement-related damage. Complement has also been shown to participate in the generation of normal humoral immune responses to foreign antigens. Recent studies suggest that the functions of complement may be extended to include the maintenance of B cell tolerance. Complement receptor 2 (CR2/CD21) has been implicated in lupus susceptibility in both humans and animal models of disease. Located primarily on B cells and follicular dendritic cells, CR2 binds C3 degradation products that have become covalently bound to antigen or immune complexes in the process of complement activation. The mechanism by which CR2 might regulate B cell reactivity to autoantigens has not been elucidated, but may involve direct effects on B cell tolerance or indirect effects on T cell tolerance.
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Affiliation(s)
- Susan A Boackle
- University of Colorado, Health Sciences Center, 4200 East Ninth Avenue, Box B115, Denver, CO 80262, USA.
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31
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Saito T, Chiba S, Ichikawa M, Kunisato A, Asai T, Shimizu K, Yamaguchi T, Yamamoto G, Seo S, Kumano K, Nakagami-Yamaguchi E, Hamada Y, Aizawa S, Hirai H. Notch2 is preferentially expressed in mature B cells and indispensable for marginal zone B lineage development. Immunity 2003; 18:675-85. [PMID: 12753744 DOI: 10.1016/s1074-7613(03)00111-0] [Citation(s) in RCA: 420] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The Notch genes play a key role in cellular differentiation. The significance of Notch1 during thymocyte development is well characterized, but the function of Notch2 is poorly understood. Here we demonstrate that Notch2 but no other Notch family member is preferentially expressed in mature B cells and that conditionally targeted deletion of Notch2 results in the defect of marginal zone B (MZB) cells and their presumed precursors, CD1d(hi) fraction of type 2 transitional B cells. Among Notch target genes, the expression level of Deltex1 is prominent in MZB cells and strictly dependent on that of Notch2, suggesting that Deltex1 may play a role in MZB cell differentiation.
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Affiliation(s)
- Toshiki Saito
- Department of Hematology and Oncology, Graduate School of Medicine, University of Tokyo, Japan
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Ulgiati D, Pham C, Holers VM. Functional analysis of the human complement receptor 2 (CR2/CD21) promoter: characterization of basal transcriptional mechanisms. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:6279-85. [PMID: 12055242 DOI: 10.4049/jimmunol.168.12.6279] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Human complement receptor (CR) type 2 (CR2/CD21) is a 145-kDa membrane protein encoded within the regulators of complement activation gene cluster localized on human chromosome 1q32. Understanding the mechanisms that regulate CR2 expression is important because CR2 is expressed during specific stages of B cell development, and several lines of evidence suggest a role for altered CR2 function or expression in a number of autoimmune diseases. Additionally, even modest changes in CR2 expression are likely to affect relative B cell responses. In this study we have delineated the transcriptional requirements of the human CR2 gene. We have studied the human CR2 proximal promoter and identified sites important for controlling the level of transcription in CR2-expressing cells. We have determined that four functionally relevant sites lie within very close proximity to the transcriptional initiation site. These sites bind the transcription factors USF1, an AP-2-like transcription factor, and Sp1.
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Affiliation(s)
- Daniela Ulgiati
- Department of Immunology, Division of Rheumatology, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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Ulgiati D, Holers VM. CR2/CD21 proximal promoter activity is critically dependent on a cell type-specific repressor. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:6912-9. [PMID: 11739509 DOI: 10.4049/jimmunol.167.12.6912] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Transcription of the human complement receptor type 2 (CR2/CD21) gene is controlled by both proximal promoter and intronic elements. CR2 is primarily expressed on B cells from the immature through mature cell stages. We have previously described the presence of an intronic element that is required for both cell- and stage-specific expression of CR2. In this study, we report the identification of a cell type-specific repressor element within the proximal promoter. This repressor sequence is shown by linker scanning mutagenesis to comprise an E box motif. By supershift analysis this element binds members of the basic helix-loop-helix family of proteins, in particular E2A gene products. Mutational analysis demonstrates that binding of E2A proteins is critical for functioning of this repressor. Thus, E2A activity is key not only for early B cell development, but also for controlling CR2 expression, a gene expressed only during later stages of ontogeny.
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Affiliation(s)
- D Ulgiati
- Department of Immunology and Medicine, University of Colorado Health Sciences Center, Denver, CO 80262, USA
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