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Zhang T, Sun J, Cheng J, Yin W, Li J, Miller H, Herrada AA, Gu H, Song H, Chen Y, Gong Q, Liu C. The role of ubiquitinase in B cell development and function. J Leukoc Biol 2020; 109:395-405. [PMID: 32816356 DOI: 10.1002/jlb.1mr0720-185rr] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 07/16/2020] [Accepted: 07/18/2020] [Indexed: 11/10/2022] Open
Abstract
Ubiquitinases are a select group of enzymes that modify target proteins through ubiquitination, which plays a crucial role in the regulation of protein degradation, location, and function. B lymphocytes that originated from bone marrow hematopoietic stem cells (HSC), exert humoral immune functions by differentiating into plasma cells and producing antibodies. Previous studies have shown that ubiquitination is involved in the regulation of the cell cycle and signal transduction important for B lymphocyte development and function. In this review, how ubiquitinases regulate B cell development, activation, apoptosis, and proliferation is discussed, which could help in understanding the physiological processes and diseases related to B cells and also provides potential new targets for further studies.
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Affiliation(s)
- Tong Zhang
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jianxuan Sun
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jiali Cheng
- Department of hematology, Tongji Hospital, Tongji Medical college, Huazhong University of Science and Technology, Wuhan, China
| | - Wei Yin
- Wuhan Children's Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jingwen Li
- Department of hematology, Wuhan Union Hospital, Tongji Medical college, Huazhong University of Science and Technology, Wuhan, China
| | - Heather Miller
- Department of Intracellular Pathogens, National Institute of Allergy and Infectious Diseases, Bethesda, Maryland, USA
| | - Andrés A Herrada
- Lymphatic and Inflammation Research Laboratory, Facultad de Ciencias de la Salud, Instituto de Ciencias Biomédicas, Universidad Autónoma de Chile, Talca, Chile
| | - Heng Gu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Hongmei Song
- Department of Pediatrics, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, No 1, Shuaifuyuan, Dongcheng District, Beijing, China
| | - Yan Chen
- The Second Department of Pediatrics, Affiliated Hospital of Zunyi Medical University, Zunyi, Guizhou, China
| | - Quan Gong
- Department of Immunology, School of Medicine, Yangtze University, Jingzhou, China.,Clinical Molecular Immunology Center, School of Medicine, Yangtze University, Jingzhou, China
| | - Chaohong Liu
- Department of Pathogen Biology, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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2
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McLean KC, Mandal M. It Takes Three Receptors to Raise a B Cell. Trends Immunol 2020; 41:629-642. [PMID: 32451219 DOI: 10.1016/j.it.2020.05.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2020] [Revised: 05/03/2020] [Accepted: 05/04/2020] [Indexed: 12/14/2022]
Abstract
As the unique source of diverse immunoglobulin repertoires, B lymphocytes are an indispensable part of humoral immunity. B cell progenitors progress through sequential and mutually exclusive states of proliferation and recombination, coordinated by cytokines and chemokines. Mutations affecting the crucial pre-B cell checkpoint result in immunodeficiency, autoimmunity, and leukemia. This checkpoint was previously modeled by the signaling of two opposing receptors, IL-7R and the pre-BCR. We provide an update to this model in which three receptors, IL-7R, pre-BCR, and CXCR4, work in concert to coordinate both the proper positioning of B cell progenitors in the bone marrow (BM) microenvironment and their progression through the pre-B checkpoint. Furthermore, signaling initiated by all three receptors directly instructs cell fate and developmental progression.
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Affiliation(s)
- Kaitlin C McLean
- Section of Rheumatology, and Gwen Knapp Center for Lupus and Immunology Research, Department of Medicine, University of Chicago, IL 60637, USA
| | - Malay Mandal
- Section of Rheumatology, and Gwen Knapp Center for Lupus and Immunology Research, Department of Medicine, University of Chicago, IL 60637, USA.
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3
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Mandal M, Okoreeh MK, Kennedy DE, Maienschein-Cline M, Ai J, McLean KC, Kaverina N, Veselits M, Aifantis I, Gounari F, Clark MR. CXCR4 signaling directs Igk recombination and the molecular mechanisms of late B lymphopoiesis. Nat Immunol 2019; 20:1393-1403. [PMID: 31477919 PMCID: PMC6754289 DOI: 10.1038/s41590-019-0468-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 07/16/2019] [Indexed: 12/17/2022]
Abstract
In B lymphopoiesis, activation of the pre-B cell antigen receptor (pre-BCR) is associated with both cell cycle exit and Igk recombination. Yet how the pre-BCR mediates these functions remains unclear. Here, we demonstrate that the pre-BCR initiates a feed-forward amplification loop mediated by the transcription factor interferon regulatory factor 4 and the chemokine receptor C-X-C motif chemokine receptor 4 (CXCR4). CXCR4 ligation by C-X-C motif chemokine ligand 12 activates the mitogen-activated protein kinase extracellular-signal-regulated kinase, which then directs the development of small pre- and immature B cells, including orchestrating cell cycle exit, pre-BCR repression, Igk recombination and BCR expression. In contrast, pre-BCR expression and escape from interleukin-7 have only modest effects on B cell developmental transcriptional and epigenetic programs. These data show a direct and central role for CXCR4 in orchestrating late B cell lymphopoiesis. Furthermore, in the context of previous findings, our data provide a three-receptor system sufficient to recapitulate the essential features of B lymphopoiesis in vitro.
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Affiliation(s)
- Malay Mandal
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA.
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA.
| | - Michael K Okoreeh
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | - Domenick E Kennedy
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | | | - Junting Ai
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | - Kaitlin C McLean
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | - Natalya Kaverina
- Division of Nephrology, University of Washington, Seattle, WA, USA
| | - Margaret Veselits
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | - Iannis Aifantis
- Department of Pathology, NYU School of Medicine, New York, NY, USA
- Laura and Isaac Perlmutter Cancer Center, NYU School of Medicine, New York, NY, USA
| | - Fotini Gounari
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA
| | - Marcus R Clark
- Department of Medicine, Section of Rheumatology, University of Chicago, Chicago, IL, USA.
- Gwen Knapp Center for Lupus and Immunology Research, University of Chicago, Chicago, IL, USA.
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4
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Winkler TH, Mårtensson IL. The Role of the Pre-B Cell Receptor in B Cell Development, Repertoire Selection, and Tolerance. Front Immunol 2018; 9:2423. [PMID: 30498490 PMCID: PMC6249383 DOI: 10.3389/fimmu.2018.02423] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 10/01/2018] [Indexed: 11/18/2022] Open
Abstract
Around four decades ago, it had been observed that there were cell lines as well as cells in the fetal liver that expressed antibody μ heavy (μH) chains in the apparent absence of bona fide light chains. It was thus possible that these cells expressed another molecule(s), that assembled with μH chains. The ensuing studies led to the discovery of the pre-B cell receptor (pre-BCR), which is assembled from Ig μH and surrogate light (SL) chains, together with the signaling molecules Igα and β. It is expressed on a fraction of pro-B (pre-BI) cells and most large pre-B(II) cells, and has been implicated in IgH chain allelic exclusion and down-regulation of the recombination machinery, assessment of the expressed μH chains and shaping the IgH repertoire, transition from the pro-B to pre-B stage, pre-B cell expansion, and cessation.
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Affiliation(s)
- Thomas H Winkler
- Chair of Genetics, Department of Biology, Nikolaus-Fiebiger-Center for Molecular Medicine, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen, Germany
| | - Inga-Lill Mårtensson
- Department of Rheumatology and Inflammation Research, Institute of Medicine, The Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden
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5
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Yang Y, Kong S, Zhang Y, Melo-Cardenas J, Gao B, Zhang Y, Zhang DD, Zhang B, Song J, Thorp E, Zhang K, Zhang J, Fang D. The endoplasmic reticulum-resident E3 ubiquitin ligase Hrd1 controls a critical checkpoint in B cell development in mice. J Biol Chem 2018; 293:12934-12944. [PMID: 29907570 DOI: 10.1074/jbc.ra117.001267] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2017] [Revised: 05/21/2018] [Indexed: 11/06/2022] Open
Abstract
Humoral immunity involves multiple checkpoints that occur in B cell development, maturation, and activation. The pre-B-cell receptor (pre-BCR) is expressed following the productive recombination of the immunoglobulin heavy-chain gene, and sSignalsing through the pre-BCR are required for the differentiation of pre-B cells into immature B cells. However, the molecular mechanisms controlling the pre-BCR expression and signaling strength remain undefined. Herein, we probed the role of the endoplasmic reticulum-associated, stress-activated E3 ubiquitin ligase HMG-CoA reductase degradation 1 (Hrd1) in B cell differentiation. Using mice with a specific Hrd1 deletion in pro-B cells and subsequent B cell developmental stages, we showed that the E3 ubiquitin ligase Hrd1 governs a critical checkpoint during B cell development. We observed that Hrd1 is required for degradation of the pre-BCR complex during the early stage of B cell development. As a consequence, loss of Hrd1 in the B cell lineage resulted in increased pre-BCR expression levels and a developmental defect in the transition from large to small pre-B cells. This defect, in turn, resulted in reduced fewer mature B cells in bone marrow and peripheral lymphoid organs. Our results revealed a novel critical role of Hrd1 in controlling a critical checkpoint in B cell-mediated immunity and suggest that Hrd1 may functioning as an E3 ubiquitin ligase of the pre-BCR complex.
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Affiliation(s)
- Yi Yang
- Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu Province 215123, China; Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Sinyi Kong
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Yana Zhang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611; Department of Otolaryngology, Head and Neck Surgery of Guangzhou Women and Children's Medical Center, Guangzhou, Guangdong 510623, China
| | - Johanna Melo-Cardenas
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Beixue Gao
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Yusi Zhang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Donna D Zhang
- Department of Pharmacology and Toxicology, University of Arizona, Tucson, Arizona 85721
| | - Bin Zhang
- Department of Medicine, Division of Hematology/Oncology, Robert H. Lurie Comprehensive Cancer Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Jianxun Song
- Department of Microbiology and Immunology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 16801
| | - Edward Thorp
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611
| | - Kezhong Zhang
- Department of Immunology and Microbiology, Center for Molecular Medicine and Genetics, Wayne State University School of Medicine, Detroit, Michigan 48201
| | - Jinping Zhang
- Institutes of Biology and Medical Sciences, Soochow University, Suzhou, Jiangsu Province 215123, China.
| | - Deyu Fang
- Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, Illinois 60611.
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van Beek AA, Sovran B, Hugenholtz F, Meijer B, Hoogerland JA, Mihailova V, van der Ploeg C, Belzer C, Boekschoten MV, Hoeijmakers JHJ, Vermeij WP, de Vos P, Wells JM, Leenen PJM, Nicoletti C, Hendriks RW, Savelkoul HFJ. Supplementation with Lactobacillus plantarum WCFS1 Prevents Decline of Mucus Barrier in Colon of Accelerated Aging Ercc1-/Δ7 Mice. Front Immunol 2016; 7:408. [PMID: 27774093 PMCID: PMC5054004 DOI: 10.3389/fimmu.2016.00408] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2016] [Accepted: 09/22/2016] [Indexed: 11/23/2022] Open
Abstract
Although it is clear that probiotics improve intestinal barrier function, little is known about the effects of probiotics on the aging intestine. We investigated effects of 10-week bacterial supplementation of Lactobacillus plantarum WCFS1, Lactobacillus casei BL23, or Bifidobacterium breve DSM20213 on gut barrier and immunity in 16-week-old accelerated aging Ercc1−/Δ7 mice, which have a median lifespan of ~20 weeks, and their wild-type littermates. The colonic barrier in Ercc1−/Δ7 mice was characterized by a thin (< 10 μm) mucus layer. L. plantarum prevented this decline in mucus integrity in Ercc1−/Δ7 mice, whereas B. breve exacerbated it. Bacterial supplementations affected the expression of immune-related genes, including Toll-like receptor 4. Regulatory T cell frequencies were increased in the mesenteric lymph nodes of L. plantarum- and L. casei-treated Ercc1−/Δ7 mice. L. plantarum- and L. casei-treated Ercc1−/Δ7 mice showed increased specific antibody production in a T cell-dependent immune response in vivo. By contrast, the effects of bacterial supplementation on wild-type control mice were negligible. Thus, supplementation with L. plantarum – but not with L. casei and B. breve – prevented the decline in the mucus barrier in Ercc1−/Δ7 mice. Our data indicate that age is an important factor influencing beneficial or detrimental effects of candidate probiotics. These findings also highlight the need for caution in translating beneficial effects of probiotics observed in young animals or humans to the elderly.
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Affiliation(s)
- Adriaan A van Beek
- Cell Biology and Immunology Group, Wageningen University, Wageningen, Netherlands; Top Institute Food and Nutrition, Wageningen, Netherlands; Gut Health and Food Safety, Institute of Food Research, Norwich, UK
| | - Bruno Sovran
- Top Institute Food and Nutrition, Wageningen, Netherlands; Host Microbe Interactomics, Wageningen University, Wageningen, Netherlands
| | - Floor Hugenholtz
- Top Institute Food and Nutrition, Wageningen, Netherlands; Laboratory of Microbiology, Wageningen University, Wageningen, Netherlands
| | - Ben Meijer
- Cell Biology and Immunology Group, Wageningen University , Wageningen , Netherlands
| | - Joanne A Hoogerland
- Cell Biology and Immunology Group, Wageningen University , Wageningen , Netherlands
| | - Violeta Mihailova
- Cell Biology and Immunology Group, Wageningen University , Wageningen , Netherlands
| | - Corine van der Ploeg
- Cell Biology and Immunology Group, Wageningen University , Wageningen , Netherlands
| | - Clara Belzer
- Top Institute Food and Nutrition, Wageningen, Netherlands; Laboratory of Microbiology, Wageningen University, Wageningen, Netherlands
| | - Mark V Boekschoten
- Top Institute Food and Nutrition, Wageningen, Netherlands; Human Nutrition, Wageningen University, Wageningen, Netherlands
| | - Jan H J Hoeijmakers
- Department of Molecular Genetics, Erasmus University Medical Center, Rotterdam, Netherlands; CECAD Forschungszentrum, Universität zu Köln, Köln, Germany
| | - Wilbert P Vermeij
- Department of Molecular Genetics, Erasmus University Medical Center , Rotterdam , Netherlands
| | - Paul de Vos
- Top Institute Food and Nutrition, Wageningen, Netherlands; University of Groningen, Groningen, Netherlands
| | - Jerry M Wells
- Top Institute Food and Nutrition, Wageningen, Netherlands; Host Microbe Interactomics, Wageningen University, Wageningen, Netherlands
| | - Pieter J M Leenen
- Department of Immunology, Erasmus University Medical Center , Rotterdam , Netherlands
| | - Claudio Nicoletti
- Gut Health and Food Safety, Institute of Food Research, Norwich, UK; Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus University Medical Center , Rotterdam , Netherlands
| | - Huub F J Savelkoul
- Cell Biology and Immunology Group, Wageningen University, Wageningen, Netherlands; Top Institute Food and Nutrition, Wageningen, Netherlands
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7
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Ji Y, Kim H, Yang L, Sha H, Roman CA, Long Q, Qi L. The Sel1L-Hrd1 Endoplasmic Reticulum-Associated Degradation Complex Manages a Key Checkpoint in B Cell Development. Cell Rep 2016; 16:2630-2640. [PMID: 27568564 DOI: 10.1016/j.celrep.2016.08.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2016] [Revised: 07/06/2016] [Accepted: 07/31/2016] [Indexed: 01/09/2023] Open
Abstract
Endoplasmic reticulum (ER)-associated degradation (ERAD) is a principal mechanism that targets ER-associated proteins for cytosolic proteasomal degradation. Here, our data demonstrate a critical role for the Sel1L-Hrd1 complex, the most conserved branch of ERAD, in early B cell development. Loss of Sel1L-Hrd1 ERAD in B cell precursors leads to a severe developmental block at the transition from large to small pre-B cells. Mechanistically, we show that Sel1L-Hrd1 ERAD selectively recognizes and targets the pre-B cell receptor (pre-BCR) for proteasomal degradation in a BiP-dependent manner. The pre-BCR complex accumulates both intracellularly and at the cell surface in Sel1L-deficient pre-B cells, leading to persistent pre-BCR signaling and pre-B cell proliferation. This study thus implicates ERAD mediated by Sel1L-Hrd1 as a key regulator of B cell development and reveals the molecular mechanism underpinning the transient nature of pre-BCR signaling.
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Affiliation(s)
- Yewei Ji
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Hana Kim
- Graduate Field of Immunology and Infectious Disease, Cornell University, Ithaca, NY 14853, USA
| | - Liu Yang
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Haibo Sha
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA
| | - Christopher A Roman
- Department of Cell Biology, College of Medicine and Program in Molecular and Cellular Biology, The School of Graduate Studies, State University of New York, Downstate Medical Center at Brooklyn, New York, NY 11203, USA
| | - Qiaoming Long
- Laboratory Animal Research Center, Medical College of Soochow University, Suzhou 215006, Jiangsu, China
| | - Ling Qi
- Division of Nutritional Sciences, Cornell University, Ithaca, NY 14853, USA; Graduate Field of Immunology and Infectious Disease, Cornell University, Ithaca, NY 14853, USA.
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8
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Urquhart KR, Zhao Y, Baker JA, Lu Y, Yan L, Cook MN, Jones BC, Hamre KM, Lu L. A novel heat shock protein alpha 8 (Hspa8) molecular network mediating responses to stress- and ethanol-related behaviors. Neurogenetics 2016; 17:91-105. [PMID: 26780340 DOI: 10.1007/s10048-015-0470-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2015] [Accepted: 12/10/2015] [Indexed: 12/15/2022]
Abstract
Genetic differences mediate individual differences in susceptibility and responses to stress and ethanol, although, the specific molecular pathways that control these responses are not fully understood. Heat shock protein alpha 8 (Hspa8) is a molecular chaperone and member of the heat shock protein family that plays an integral role in the stress response and that has been implicated as an ethanol-responsive gene. Therefore, we assessed its role in mediating responses to stress and ethanol across varying genetic backgrounds. The hippocampus is an important mediator of these responses, and thus, was examined in the BXD family of mice in this study. We conducted bioinformatic analyses to dissect genetic factors modulating Hspa8 expression, identify downstream targets of Hspa8, and examined its role. Hspa8 is trans-regulated by a gene or genes on chromosome 14 and is part of a molecular network that regulates stress- and ethanol-related behaviors. To determine additional components of this network, we identified direct or indirect targets of Hspa8 and show that these genes, as predicted, participate in processes such as protein folding and organic substance metabolic processes. Two phenotypes that map to the Hspa8 locus are anxiety-related and numerous other anxiety- and/or ethanol-related behaviors significantly correlate with Hspa8 expression. To more directly assay this relationship, we examined differences in gene expression following exposure to stress or alcohol and showed treatment-related differential expression of Hspa8 and a subset of the members of its network. Our findings suggest that Hspa8 plays a vital role in genetic differences in responses to stress and ethanol and their interactions.
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Affiliation(s)
- Kyle R Urquhart
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Yinghong Zhao
- Department of Neurology, Affiliated Hospital of Nantong University, Nantong, Jiangsu, China
| | - Jessica A Baker
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Ye Lu
- The International Hospital of Zhejiang University, Hangzhou, Zhejiang, China
| | - Lei Yan
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Melloni N Cook
- Department of Psychology, University of Memphis, Memphis, TN, 38152, USA
| | - Byron C Jones
- Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38163, USA
| | - Kristin M Hamre
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA.
| | - Lu Lu
- Department of Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN, 38163, USA. .,Department of Genetics, Genomics and Informatics, University of Tennessee Health Science Center, Memphis, TN, 38163, USA. .,Jiangsu Province Key Laboratory for Inflammation and Molecular Drug Target, Medical College of Nantong University, Nantong, China.
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9
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Übelhart R, Jumaa H. Autoreactivity and the positive selection of B cells. Eur J Immunol 2015; 45:2971-7. [DOI: 10.1002/eji.201444622] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2014] [Revised: 07/08/2015] [Accepted: 08/13/2015] [Indexed: 11/09/2022]
Affiliation(s)
- Rudolf Übelhart
- Institute of Immunology; University Hospital Ulm; Ulm Germany
| | - Hassan Jumaa
- Institute of Immunology; University Hospital Ulm; Ulm Germany
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10
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Kil LP, Corneth OB, de Bruijn MJ, Asmawidjaja PS, Krause A, Lubberts E, van Loo PF, Hendriks RW. Surrogate light chain expression beyond the pre-B cell stage promotes tolerance in a dose-dependent fashion. J Autoimmun 2015; 57:30-41. [DOI: 10.1016/j.jaut.2014.11.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Revised: 11/20/2014] [Accepted: 11/27/2014] [Indexed: 10/24/2022]
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11
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de Almeida CR, Hendriks RW, Stadhouders R. Dynamic Control of Long-Range Genomic Interactions at the Immunoglobulin κ Light-Chain Locus. Adv Immunol 2015; 128:183-271. [DOI: 10.1016/bs.ai.2015.07.004] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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12
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Corneth OBJ, Klein Wolterink RGJ, Hendriks RW. BTK Signaling in B Cell Differentiation and Autoimmunity. Curr Top Microbiol Immunol 2015; 393:67-105. [PMID: 26341110 DOI: 10.1007/82_2015_478] [Citation(s) in RCA: 59] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Since the original identification of Bruton's tyrosine kinase (BTK) as the gene defective in the primary immunodeficiency X-linked agammaglobulinemia (XLA) in 1993, our knowledge on the physiological function of BTK has expanded impressively. In this review, we focus on the role of BTK during B cell differentiation in vivo, both in the regulation of expansion and in the developmental progression of pre-B cells in the bone marrow and as a crucial signal transducer of signals downstream of the IgM or IgG B cell antigen receptor (BCR) in mature B cells governing proliferation, survival, and differentiation. In particular, we highlight BTK function in B cells in the context of host defense and autoimmunity. Small-molecule inhibitors of BTK have very recently shown impressive anti-tumor activity in clinical studies in patients with various B cell malignancies. Since promising effects of BTK inhibition were also seen in experimental animal models for lupus and rheumatoid arthritis, BTK may be a good target for controlling autoreactive B cells in patients with systemic autoimmune disease.
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Affiliation(s)
- Odilia B J Corneth
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands
| | - Roel G J Klein Wolterink
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands
| | - Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC Rotterdam, Room Ee2251a, PO Box 2040, NL 3000, CA, Rotterdam, The Netherlands.
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13
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García-Muñoz R, Feliu J, Llorente L. The top ten clues to understand the origin of chronic lymphocytic leukemia (CLL). J Autoimmun 2015; 56:81-6. [DOI: 10.1016/j.jaut.2014.10.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2012] [Revised: 10/12/2014] [Accepted: 10/18/2014] [Indexed: 11/24/2022]
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14
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Liu GJ, Cimmino L, Jude JG, Hu Y, Witkowski MT, McKenzie MD, Kartal-Kaess M, Best SA, Tuohey L, Liao Y, Shi W, Mullighan CG, Farrar MA, Nutt SL, Smyth GK, Zuber J, Dickins RA. Pax5 loss imposes a reversible differentiation block in B-progenitor acute lymphoblastic leukemia. Genes Dev 2014; 28:1337-50. [PMID: 24939936 PMCID: PMC4066403 DOI: 10.1101/gad.240416.114] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Loss-of-function mutations in hematopoietic transcription factors occur in most cases of B-progenitor acute lymphoblastic leukemia (B-ALL). Here, Liu et al. used transgenic RNAi to reversibly suppress endogenous Pax5 expression in the hematopoietic compartment of mice. Restoring Pax5 expression in established B-ALL triggers immunophenotypic maturation and durable disease remission by engaging a transcriptional program reminiscent of normal B-cell differentiation. Similar findings in human B-ALL cell lines establish that Pax5 hypomorphism promotes B-ALL self-renewal by impairing a differentiation program that can be re-engaged despite the presence of additional oncogenic lesions. Loss-of-function mutations in hematopoietic transcription factors including PAX5 occur in most cases of B-progenitor acute lymphoblastic leukemia (B-ALL), a disease characterized by the accumulation of undifferentiated lymphoblasts. Although PAX5 mutation is a critical driver of B-ALL development in mice and humans, it remains unclear how its loss contributes to leukemogenesis and whether ongoing PAX5 deficiency is required for B-ALL maintenance. Here we used transgenic RNAi to reversibly suppress endogenous Pax5 expression in the hematopoietic compartment of mice, which cooperates with activated signal transducer and activator of transcription 5 (STAT5) to induce B-ALL. In this model, restoring endogenous Pax5 expression in established B-ALL triggers immunophenotypic maturation and durable disease remission by engaging a transcriptional program reminiscent of normal B-cell differentiation. Notably, even brief Pax5 restoration in B-ALL cells causes rapid cell cycle exit and disables their leukemia-initiating capacity. These and similar findings in human B-ALL cell lines establish that Pax5 hypomorphism promotes B-ALL self-renewal by impairing a differentiation program that can be re-engaged despite the presence of additional oncogenic lesions. Our results establish a causal relationship between the hallmark genetic and phenotypic features of B-ALL and suggest that engaging the latent differentiation potential of B-ALL cells may provide new therapeutic entry points.
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Affiliation(s)
- Grace J Liu
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Luisa Cimmino
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Julian G Jude
- Research Institute of Molecular Pathology, Vienna Biocenter, A-1030 Vienna, Austria
| | - Yifang Hu
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Victoria, Australia
| | - Matthew T Witkowski
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Mark D McKenzie
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Mutlu Kartal-Kaess
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Sarah A Best
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Laura Tuohey
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Yang Liao
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Victoria, Australia; Department of Computing and Information Systems, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Wei Shi
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Victoria, Australia; Department of Computing and Information Systems, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Charles G Mullighan
- Department of Pathology, St. Jude Children's Research Hospital, Memphis, Tennessee 38105, USA
| | - Michael A Farrar
- Department of Laboratory Medicine and Pathology, Center for Immunology, The Masonic Cancer Center, University of Minnesota, Minneapolis, Minnesota 55455, USA
| | - Stephen L Nutt
- Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia; Molecular Immunology Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia
| | - Gordon K Smyth
- Bioinformatics Division, Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Victoria, Australia; Department of Mathematics and Statistics, University of Melbourne, Parkville, Victoria 3010, Australia
| | - Johannes Zuber
- Research Institute of Molecular Pathology, Vienna Biocenter, A-1030 Vienna, Austria
| | - Ross A Dickins
- Molecular Medicine Division, Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria 3052, Australia; Department of Medical Biology, University of Melbourne, Parkville, Victoria 3010, Australia
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15
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García-Muñoz R, Llorente L. Chronic lymphocytic leukaemia: could immunological tolerance mechanisms be the origin of lymphoid neoplasms? Immunology 2014; 142:536-50. [PMID: 24645778 PMCID: PMC4107664 DOI: 10.1111/imm.12285] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2014] [Revised: 03/06/2014] [Accepted: 03/13/2014] [Indexed: 12/12/2022] Open
Abstract
Immunological tolerance theory in chronic lymphocytic leukaemia (CLL): we suggest that B cells that express B-cell receptors (BCR) that recognize their own BCR epitopes are viewed by immune system as 'dangerous cells'. BCR autonomous signalling may induce constant receptor editing and mistakes in allelic exclusion. The fact that whole BCR recognizes a self-antigen or foreing antigen may be irrelevant in early B cell development. In early B cells, autonomous signalling induced by recognition of the BCR's own epitopes simulates an antigen-antibody engagement. In the bone marrow this interaction is viewed as recognition of self-molecules and induces receptor editing. In mature B cells autonomous signalling by the BCR may promote 'reversible anergy' and also may correct self-reactivity induced by the somatic hypermutation mechanisms in mutated CLL B cells. However, in unmutated CLL B cells, BCR autonomous signalling in addition to self-antigen recognition augments B cell activation, proliferation and genomic instability. We suggest that CLL originates from a coordinated normal immunologic tolerance mechanism to destroy self-reactive B cells. Additional genetic damage induced by tolerance mechanisms may immortalize self-reactive B cells and transform them into a leukemia.
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Affiliation(s)
| | - Luis Llorente
- Department of Immunology and Rheumatology, Instituto Nacional de Ciencias Médicas y Nutrición Salvador ZubiránMéxico City, México
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16
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Abstract
Bruton's tyrosine kinase (BTK) is a key component of B cell receptor (BCR) signalling and functions as an important regulator of cell proliferation and cell survival in various B cell malignancies. Small-molecule inhibitors of BTK have shown antitumour activity in animal models and, recently, in clinical studies. High response rates were reported in patients with chronic lymphocytic leukaemia and mantle cell lymphoma. Remarkably, BTK inhibitors have molecular effects that cannot be explained by the classic role of BTK in BCR signalling. In this Review, we highlight the importance of BTK in various signalling pathways in the context of its therapeutic inhibition.
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Affiliation(s)
- Rudi W Hendriks
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
| | - Saravanan Yuvaraj
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
| | - Laurens P Kil
- Department of Pulmonary Medicine, Room Ee2251a, Erasmus MC Rotterdam, PO Box 2040, NL 3000 CA Rotterdam, the Netherlands
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17
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Zouali M. Transcriptional and metabolic pre-B cell receptor-mediated checkpoints: implications for autoimmune diseases. Mol Immunol 2014; 62:315-20. [PMID: 24602812 DOI: 10.1016/j.molimm.2014.01.009] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2013] [Revised: 01/10/2014] [Accepted: 01/13/2014] [Indexed: 02/01/2023]
Abstract
At the pre-B cell stage of lymphocyte development, immunoglobulin light-chains are not yet produced, and heavy-chains are covalently linked to surrogate light-chains composed of VpreB and λ5 to form the pre-B cell receptor (pre-BCR) in a non-covalent association with signal-transducing modules. Even tough the pre-BCR does not have the potential to bind conventional antigens, accumulating evidence indicates that pre-BCR-mediated checkpoints are important both for negative and positive selection of self-reactivity, and that defects in these regulatory nodes may be associated with autoimmune disease. Thus, the transcription factor BACH2, which represents a susceptibility locus for rheumatoid arthritis, has recently emerged as a crucial mediator of negative selection at a pre-BCR checkpoint. The lysosome-associated protein LAPTM5, which is highly expressed in an animal model of Sjögren's syndrome, plays a role in down-modulation of the pre-BCR. Studies of copy number variation in rheumatoid arthritis suggest that a reduced dosage of the VPREB1 gene is involved in disease pathogenesis. Notably, animal models of autoimmune disease exhibit defects in pre-B to naïve B cell checkpoints. Administration of a pre-BCR ligand, which also plays a role in anergy both in human and murine B lymphocytes, ameliorates disease in experimental models of autoimmunity. Further investigation is required to gain a better insight into the molecular mechanisms of pre-BCR-mediated checkpoints and to determine their relevance to autoimmune diseases.
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Affiliation(s)
- Moncef Zouali
- Inserm, UMR 1132, F-75475 Paris, France; Université Paris Diderot, Sorbone Paris Cité, F-75475 Paris, France.
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18
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19
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Orchestrating B cell lymphopoiesis through interplay of IL-7 receptor and pre-B cell receptor signalling. Nat Rev Immunol 2013; 14:69-80. [PMID: 24378843 DOI: 10.1038/nri3570] [Citation(s) in RCA: 216] [Impact Index Per Article: 19.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The development of B cells is dependent on the sequential DNA rearrangement of immunoglobulin loci that encode subunits of the B cell receptor. The pathway navigates a crucial checkpoint that ensures expression of a signalling-competent immunoglobulin heavy chain before commitment to rearrangement and expression of an immunoglobulin light chain. The checkpoint segregates proliferation of pre-B cells from immunoglobulin light chain recombination and their differentiation into B cells. Recent advances have revealed the molecular circuitry that controls two rival signalling systems, namely the interleukin-7 (IL-7) receptor and the pre-B cell receptor, to ensure that proliferation and immunoglobulin recombination are mutually exclusive, thereby maintaining genomic integrity during B cell development.
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20
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Hauser J, Verma-Gaur J, Grundström T. Broad feedback inhibition of pre-B-cell receptor signaling components. Mol Immunol 2013; 54:247-53. [DOI: 10.1016/j.molimm.2012.12.002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 11/28/2012] [Accepted: 12/04/2012] [Indexed: 11/13/2022]
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21
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Ta VBT, de Bruijn MJW, Matheson L, Zoller M, Bach MP, Wardemann H, Jumaa H, Corcoran A, Hendriks RW. Highly Restricted Usage of Ig H Chain VH14 Family Gene Segments in Slp65-Deficient Pre-B Cell Leukemia in Mice. THE JOURNAL OF IMMUNOLOGY 2012; 189:4842-51. [DOI: 10.4049/jimmunol.1201440] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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22
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A novel mechanism for the autonomous termination of pre-B cell receptor expression via induction of lysosome-associated protein transmembrane 5. Mol Cell Biol 2012; 32:4462-71. [PMID: 22949502 DOI: 10.1128/mcb.00531-12] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
The expression of the pre-B cell receptor (BCR) is confined to the early stage of B cell development, and its dysregulation is associated with anomalies of B-lineage cells, including leukemogenesis. Previous studies suggested that the pre-BCR signal might trigger the autonomous termination of pre-BCR expression even before the silencing of pre-BCR gene expression to prevent sustained pre-BCR expression. However, the underlying mechanism remains ill defined. Here we demonstrate that the pre-BCR signal induces the expression of lysosome-associated protein transmembrane 5 (LAPTM5), which leads to the prompt downmodulation of the pre-BCR. While LAPTM5 induction had no significant impact on the internalization of cell surface pre-BCR, it elicited the translocation of a large pool of intracellular pre-BCR from the endoplasmic reticulum to the lysosomal compartment concomitantly with a drastic reduction of the level of intracellular pre-BCR proteins. This reduction was inhibited by lysosomal inhibitors, indicating the lysosomal degradation of the pre-BCR. Notably, the LAPTM5 deficiency in pre-B cells led to the augmented expression level of surface pre-BCR. Collectively, the pre-BCR induces the prompt downmodulation of its own expression through the induction of LAPTM5, which promotes the lysosomal transport and degradation of the intracellular pre-BCR pool and, hence, limits the supply of pre-BCR to the cell surface.
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23
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Herzog S, Jumaa H. Self-recognition and clonal selection: autoreactivity drives the generation of B cells. Curr Opin Immunol 2012; 24:166-72. [PMID: 22398125 DOI: 10.1016/j.coi.2012.02.004] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Revised: 01/19/2012] [Accepted: 02/06/2012] [Indexed: 11/15/2022]
Abstract
The diversity of B cell receptor (BCR) specificities is generated by VDJ recombination of gene segments during early B cell development, a process which bears the risk of producing BCRs that recognize and lead to the destruction of self-structures. Traditional thoughts have mainly focused on how such putatively dangerous specificities are dealt with and in how they contribute to the development of autoimmune diseases. However, a positive or even necessary role of self-recognition during B cell development has rarely been taken into account. Now, considerable data reveal that the pre-B cell receptor (pre-BCR), which marks an important checkpoint during B cell development, acts as a surrogate autoreactive receptor. This review outlines how autoreactivity is necessary for efficient B cell development and how autoreactive receptors drive positive selection, leading to a diverse repertoire of receptor specificities in the mature B cell pool.
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Affiliation(s)
- Sebastian Herzog
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany
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24
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Epigenetic repression of the Igk locus by STAT5-mediated recruitment of the histone methyltransferase Ezh2. Nat Immunol 2011; 12:1212-20. [PMID: 22037603 PMCID: PMC3233979 DOI: 10.1038/ni.2136] [Citation(s) in RCA: 148] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Accepted: 09/09/2011] [Indexed: 12/11/2022]
Abstract
During B lymphopoiesis, recombination of the locus encoding the immunoglobulin κ-chain complex (Igk) requires expression of the precursor to the B cell antigen receptor (pre-BCR) and escape from signaling via the interleukin 7 receptor (IL-7R). By activating the transcription factor STAT5, IL-7R signaling maintains proliferation and represses Igk germline transcription by unknown mechanisms. We demonstrate that a STAT5 tetramer bound the Igk intronic enhancer (E(κi)), which led to recruitment of the histone methyltransferase Ezh2. Ezh2 marked trimethylation of histone H3 at Lys27 (H3K27me3) throughout the κ-chain joining region (J(κ)) to the κ-chain constant region (C(κ)). In the absence of Ezh2, IL-7 failed to repress Igk germline transcription. H3K27me3 modifications were lost after termination of IL-7R-STAT5 signaling, and the transcription factor E2A bound E(κi), which resulted in acquisition of H3K4me1 and acetylated histone H4 (H4Ac). Genome-wide analyses showed a STAT5 tetrameric binding motif associated with transcriptional repression. Our data demonstrate how IL-7R signaling represses Igk germline transcription and provide a general model for STAT5-mediated epigenetic transcriptional repression.
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25
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Eschbach C, Bach MP, Fidler I, Pelanda R, Köhler F, Rajewsky K, Jumaa H. Efficient generation of B lymphocytes by recognition of self-antigens. Eur J Immunol 2011; 41:2397-403. [PMID: 21604259 DOI: 10.1002/eji.201041344] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2010] [Revised: 03/14/2011] [Accepted: 04/29/2011] [Indexed: 11/12/2022]
Abstract
Antibody diversity is generated by a random gene recombination process with the inherent risk of the production of autoreactive specificities. The current view suggests that B cells expressing such specificities are negatively selected at an early developmental stage. Using the knock-in model system of the 3-83 autoreactive B-cell antigen receptor (BCR) in combination with precursor-BCR (pre-BCR) deficiency, we show here that the 3-83 BCR mediates efficient generation of B cells in the presence, but not the absence, of a strongly recognized auto-antigen. Experiments with mixed bone marrow chimeras showed that combining the 3-83 BCR with the corresponding auto-antigen resulted in efficient reconstitution of B-cell development in immune-deficient mice. These results suggest that B cells are positively selected by recognition of self-antigens during developmental stages that precede receptor editing. Moreover, the data indicate that the pre-BCR functions as a specialized autoreactive BCR to initiate positive selection at a stage where the cells express immunoglobulin heavy but not light chains.
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Affiliation(s)
- Cathrin Eschbach
- Center for Biological Signalling Studies, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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26
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Hendriks RW, Bredius RG, Pike-Overzet K, Staal FJ. Biology and novel treatment options for XLA, the most common monogenetic immunodeficiency in man. Expert Opin Ther Targets 2011; 15:1003-21. [PMID: 21635151 DOI: 10.1517/14728222.2011.585971] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
INTRODUCTION X-linked agammaglobulinemia (XLA) is the most common primary immunodeficiency in man, and is caused by a single genetic defect. Inactivating mutations in the Bruton's tyrosine kinase (BTK) gene are invariably the cause of XLA,. XLA is characterized by a differentiation arrest at the pre-B cell stage, the absence of immunoglobulins and recurrent bacterial infections, making it an insidious disease that gradually disables the patient, and can result in death due to chronic lung disease. Current treatment involves prophylactic antibiotics and immunoglobulin infusions, which are non-curative. This disease is a good candidate for curative hematopoietic stem cell (HSC)-based gene therapy, which could correct the B cell and myeloid deficiencies. AREAS COVERED This paper reviews the basic biology of BTK in B cell development, the clinical features of XLA, and the possibilities of gene therapy for XLA, covering the literature from 1995 to 2010. EXPERT OPINION Work from various laboratories demonstrates the feasibility of using gene-corrected HSCs to complement the immune defects of Btk-deficiency in mice. We propose that it is timely to start clinical programs to develop stem cell based therapy for XLA, using gene-corrected autologous HSC.
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Affiliation(s)
- Rudi W Hendriks
- Department of Pulmonary Medicine, Erasmus MC, Rotterdam, The Netherlands
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27
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Abstract
Heavy chain diseases (HCDs) are B-cell proliferative disorders characterized by the production of monoclonal, incomplete, immunoglobulin (Ig) heavy chains (HCs) without associated light chains (LCs). These abnormal HCs are produced as a consequence of HC gene alterations in the neoplastic B cells. HC gene alterations will also impact on surface HC, which is part of the B-cell receptor (BCR), a crucial player in lymphocyte activation by antigen. The selective advantage conferred to mutant cells by abnormal BCR without an antigen-binding domain may be explained by activation of ligand-independent signaling, in analogy to what has been shown for mutated oncogenic growth factor receptors. Here we review data obtained from mouse models showing abnormal, constitutive activity of HCD-BCR, and we discuss the possible mechanism involved, namely, aberrant spontaneous self-aggregation. This self-aggregation might occur as a consequence of escape from the chaperone immunoglobulin binding protein (BiP) and from the anti-aggregation effect of LC association. The concept of misfolding-induced signaling elaborated here may extend to other pathologies termed conformational diseases.
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28
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Abstract
Engagement of the B-cell antigen receptor (BCR) or its precursor, the pre-BCR, induces a cascade of biochemical reactions that regulate the differentiation, selection, survival, and activation of B cells. This cascade is initiated by receptor-associated tyrosine kinases that activate multiple downstream signaling pathways. Since it is required for metabolism, cell growth, development, and survival, the activation of phosphoinositide 3-kinase (PI3K)-dependent pathways represents a crucial event of BCR/pre-BCR signaling. The phosphorylated substrates of the PI3K promote specific recruitment of selected signaling proteins to the plasma membrane, where important signaling complexes are formed to mediate the above-mentioned biological processes. Here, we review the principles of PI3K signaling and highlight the role of an important PI3K-driven module in VDJ recombination of immunoglobulin (Ig) genes during early B-cell development as compared with class switch recombination of Ig genes in mature B cells after activation by specific antigens. Furthermore, we discuss the role of PI3K in the survival of mature B cells, which is strictly dependent on BCR expression and basal BCR signaling.
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Affiliation(s)
- Markus Werner
- Faculty of Biology, Department of Molecular Immunology, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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29
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Yim SH, Chung YJ, Jin EH, Shim SC, Kim JY, Kim YS, Hu HJ, Shin SH, Pae HO, Zouali M, Chung HT. The potential role of VPREB1 gene copy number variation in susceptibility to rheumatoid arthritis. Mol Immunol 2010; 48:1338-43. [PMID: 21144590 DOI: 10.1016/j.molimm.2010.11.009] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2010] [Revised: 10/29/2010] [Accepted: 11/02/2010] [Indexed: 01/07/2023]
Abstract
Although the etiology of rheumatoid arthritis (RA) remains unknown, it has been widely suggested that RA has a genetic background. In humans, a copy number loss of 22q11.2, a region harboring the VPREB1 gene, has been suggested to be associated with several immunologic disorders, but there has been no study on the copy number variation (CNV) of the VPREB1 and its potential association with RA. Here, we explored the association between the RA and the CNV of the VPREB1 gene by performing genomic quantitative PCR and quantification of B cell subsets in RA patients and controls. The proportion of the individuals with <2 copies of the VPREB1 gene was significantly higher in the patient group than that in the controls (12.9% vs 0.9%, p<0.0001), while that of the individuals with >2 copies was lower in the patient group than that in the controls (1.7% vs 18.9%, p<0.0001). The odds ratio (OR) of the individuals with <2 copies was significantly higher compared with the odds ratio of those individuals with 2 copies (OR=12.1, 95% confidence interval (CI) 2.8-51.6). Likewise, the OR of the individuals with >2 copies was significantly lower than the OR of those individuals with 2 copies (OR=0.09, 95% CI 0.03-0.3). We also found that the proportion of CD21⁻CD23⁻ B cells was significantly higher in the RA patients compared with that of the controls (11.9% vs 5.7%, p=0.002), but the proportion of CD21+CD23+ cells was significantly lower in the RA patients (26.2% in RA vs 34.9% in the controls, p=0.005). To the best of our knowledge, this is the first evidence showing the association between a low copy number of the VPREB1 gene and RA, and this may help understanding the pathogenesis of RA and other autoimmune disorders.
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Affiliation(s)
- Seon-Hee Yim
- Integrated Research Center for Genome Polymorphism, The Catholic University of Korea, School of Medicine, 505 Banpo-dong, Socho gu, Seoul 137-701, Republic of Korea
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30
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Merkenschlager M. Ikaros in immune receptor signaling, lymphocyte differentiation, and function. FEBS Lett 2010; 584:4910-4. [DOI: 10.1016/j.febslet.2010.09.042] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2010] [Revised: 09/20/2010] [Accepted: 09/27/2010] [Indexed: 12/18/2022]
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31
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Kersseboom R, Kil L, Flierman R, van der Zee M, Dingjan GM, Middendorp S, Maas A, Hendriks RW. Constitutive activation of Bruton's tyrosine kinase induces the formation of autoreactive IgM plasma cells. Eur J Immunol 2010; 40:2643-54. [DOI: 10.1002/eji.201040521] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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32
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The pre-B cell receptor: turning autoreactivity into self-defense. Trends Immunol 2010; 31:176-83. [DOI: 10.1016/j.it.2010.02.004] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 02/03/2010] [Accepted: 02/25/2010] [Indexed: 11/17/2022]
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33
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Abstract
Antigen receptors on the surface of B lymphocytes trigger adaptive immune responses after encountering their cognate antigens but also control a series of antigen-independent checkpoints during B cell development. These physiological processes are regulated by the expression and function of cell surface receptors, intracellular signaling molecules, and transcription factors. The function of these proteins can be altered by a dynamic array of post-translational modifications, using two interconnected mechanisms. These modifications can directly induce an altered conformational state in the protein target of the modification itself. In addition, they can create new binding sites for other protein partners, thereby contributing to where and when such multiple protein assemblies are activated within cells. As a new type of post-transcriptional regulator, microRNAs have emerged to influence the development and function of B cells by affecting the expression of target mRNAs.
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34
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Tussiwand R, Bosco N, Ceredig R, Rolink AG. Tolerance checkpoints in B-cell development: Johnny B good. Eur J Immunol 2009; 39:2317-24. [PMID: 19714572 DOI: 10.1002/eji.200939633] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
B-cell development up to the immature B-cell stage takes place in the bone marrow, while final maturation into mature B cells occurs in the spleen. During differentiation, the precursor and immature B cells have to pass several checkpoints, including those in which they are censored for being auto-reactive, and therefore being potentially dangerous. Numerous studies have shown that the immature B-cell stage in the bone marrow and the transitional B-cell stages in the spleen comprise distinct checkpoints at which auto-reactivity is censored. Recently, evidence has been provided that the large pre-BII stage in the bone marrow, at which the pre-BCR is expressed, is yet another B-cell tolerance checkpoint. Here, we review these findings and speculate on directions for possible further experimentation.
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Affiliation(s)
- Roxane Tussiwand
- Developmental and Molecular Immunology, Department of Biomedicine, University of Basel, Mattenstrasse, Basel, Switzerland
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35
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Ras orchestrates exit from the cell cycle and light-chain recombination during early B cell development. Nat Immunol 2009; 10:1110-7. [PMID: 19734904 DOI: 10.1038/ni.1785] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2009] [Accepted: 07/27/2009] [Indexed: 12/12/2022]
Abstract
Signals through the pre-B cell antigen receptor (pre-BCR) and interleukin 7 receptor (IL-7R) coordinate pre-B cell population expansion with subsequent recombination of the locus encoding immunoglobulin kappa-chain (Igk). Although many 'downstream' effectors of each receptor are known, how they integrate to mediate development has remained unclear. Here we report that pre-BCR-mediated activation of the Ras-MEK-Erk signaling pathway silenced transcription of Ccnd3 (encoding cyclin D3) and coordinated exit from the cell cycle with induction of the transcription factor E2A and the initiation of Igk recombination. IL-7R-mediated activation of the transcription factor STAT5 opposed this pathway by promoting Ccnd3 expression and concomitantly inhibiting Igk transcription by binding to the Igk intronic enhancer and preventing E2A recruitment. Our data show how pre-BCR signaling poises pre-B cells to undergo differentiation after escape from IL-7R signaling.
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Trageser D, Iacobucci I, Nahar R, Duy C, von Levetzow G, Klemm L, Park E, Schuh W, Gruber T, Herzog S, Kim YM, Hofmann WK, Li A, Storlazzi CT, Jäck HM, Groffen J, Martinelli G, Heisterkamp N, Jumaa H, Müschen M. Pre-B cell receptor-mediated cell cycle arrest in Philadelphia chromosome-positive acute lymphoblastic leukemia requires IKAROS function. ACTA ACUST UNITED AC 2009; 206:1739-53. [PMID: 19620627 PMCID: PMC2722172 DOI: 10.1084/jem.20090004] [Citation(s) in RCA: 104] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
B cell lineage acute lymphoblastic leukemia (ALL) arises in virtually all cases from B cell precursors that are arrested at pre–B cell receptor–dependent stages. The Philadelphia chromosome–positive (Ph+) subtype of ALL accounts for 25–30% of cases of adult ALL, has the most unfavorable clinical outcome among all ALL subtypes and is defined by the oncogenic BCR-ABL1 kinase and deletions of the IKAROS gene in >80% of cases. Here, we demonstrate that the pre–B cell receptor functions as a tumor suppressor upstream of IKAROS through induction of cell cycle arrest in Ph+ ALL cells. Pre–B cell receptor–mediated cell cycle arrest in Ph+ ALL cells critically depends on IKAROS function, and is reversed by coexpression of the dominant-negative IKAROS splice variant IK6. IKAROS also promotes tumor suppression through cooperation with downstream molecules of the pre–B cell receptor signaling pathway, even if expression of the pre–B cell receptor itself is compromised. In this case, IKAROS redirects oncogenic BCR-ABL1 tyrosine kinase signaling from SRC kinase-activation to SLP65, which functions as a critical tumor suppressor downstream of the pre–B cell receptor. These findings provide a rationale for the surprisingly high frequency of IKAROS deletions in Ph+ ALL and identify IKAROS-mediated cell cycle exit as the endpoint of an emerging pathway of pre–B cell receptor–mediated tumor suppression.
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Affiliation(s)
- Daniel Trageser
- Leukemia and Lymphoma Program, Norris Comprehensive Cancer Center, University of Southern California, Los Angeles, CA 90027, USA
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Herzog S, Reth M, Jumaa H. Regulation of B-cell proliferation and differentiation by pre-B-cell receptor signalling. Nat Rev Immunol 2009; 9:195-205. [PMID: 19240758 DOI: 10.1038/nri2491] [Citation(s) in RCA: 230] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pre-B-cell receptor (pre-BCR) is expressed following the productive recombination of the immunoglobulin heavy chain gene. Signals through the pre-BCR are required for initiating diverse processes in pre-B cells, including proliferation and recombination of the light chain gene, which eventually lead to the differentiation of pre-B cells to immature B cells. However, the molecular mechanisms by which the pre-BCR promotes these processes remain largely unresolved. Recent findings suggest that forkhead box O (FOXO) transcription factors connect pre-BCR signalling to the activation of the recombination machinery. In this Review, we discuss how FOXO transcription factors are regulated by the pre-BCR to allow the progression of the cell cycle and the recombination of the light chain gene.
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Affiliation(s)
- Sebastian Herzog
- Centre for Biological Signalling Studies, Albert-Ludwigs-Universität Freiburg, Freiburg, Germany
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Köhler F, Hug E, Eschbach C, Meixlsperger S, Hobeika E, Kofer J, Wardemann H, Jumaa H. Autoreactive B cell receptors mimic autonomous pre-B cell receptor signaling and induce proliferation of early B cells. Immunity 2008; 29:912-21. [PMID: 19084434 DOI: 10.1016/j.immuni.2008.10.013] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Revised: 07/10/2008] [Accepted: 10/15/2008] [Indexed: 01/03/2023]
Abstract
The majority of early immature B cells express autoreactive B cell receptors (BCRs) that are, according to the current view, negatively selected to avoid the production of self-reactive antibodies. Here, we show that polyreactive BCRs, which recognize multiple self-antigens, induced autonomous signaling and selective expansion of B cell precursors in a manner comparable to the pre-BCR. We found that the pre-BCR was capable of recognizing multiple self-antigens and that a signaling-deficient pre-BCR lacking the non-Ig region of the surrogate-light-chain component lambda5 was rescued by the complementarity-determining region 3 derived from heavy chains of polyreactive receptors. Importantly, bone marrow B cells from mice carrying Ig transgenes for an autoreactive BCR showed increased cell-cycle activity, which could not be detected in cells lacking the transgenic BCR. Together, the pre-BCR has evolved to ensure self-recognition because autoreactivity is required for positive selection of B cell precursors.
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Affiliation(s)
- Fabian Köhler
- Department of Molecular Immunology, Faculty of Biology and Centre for Biological Signalling Studies (bioss), Albert-Ludwigs-University and Max-Planck-Institute for Immunobiology, 79108 Freiburg, Germany
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Karnowski A, Cao C, Matthias G, Carotta S, Corcoran LM, Martensson IL, Skok JA, Matthias P. Silencing and nuclear repositioning of the lambda5 gene locus at the pre-B cell stage requires Aiolos and OBF-1. PLoS One 2008; 3:e3568. [PMID: 18974788 PMCID: PMC2571989 DOI: 10.1371/journal.pone.0003568] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2008] [Accepted: 09/15/2008] [Indexed: 12/30/2022] Open
Abstract
The chromatin regulator Aiolos and the transcriptional coactivator OBF-1 have been implicated in regulating aspects of B cell maturation and activation. Mice lacking either of these factors have a largely normal early B cell development. However, when both factors are eliminated simultaneously a block is uncovered at the transition between pre-B and immature B cells, indicating that these proteins exert a critical function in developing B lymphocytes. In mice deficient for Aiolos and OBF-1, the numbers of immature B cells are reduced, small pre-BII cells are increased and a significant impairment in immunoglobulin light chain DNA rearrangement is observed. We identified genes whose expression is deregulated in the pre-B cell compartment of these mice. In particular, we found that components of the pre-BCR, such as the surrogate light chain genes λ5 and VpreB, fail to be efficiently silenced in double-mutant mice. Strikingly, developmentally regulated nuclear repositioning of the λ5 gene is impaired in pre-B cells lacking OBF-1 and Aiolos. These studies uncover a novel role for OBF-1 and Aiolos in controlling the transcription and nuclear organization of genes involved in pre-BCR function.
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Affiliation(s)
- Alexander Karnowski
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, Basel, Switzerland
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Chun Cao
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, Basel, Switzerland
| | - Gabriele Matthias
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, Basel, Switzerland
| | - Sebastian Carotta
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Lynn M. Corcoran
- The Walter and Eliza Hall Institute of Medical Research, Parkville, Victoria, Australia
| | - Inga-Lill Martensson
- Laboratory of Lymphocyte Signaling and Development, The Babraham Institute, Cambridge, United Kingdom
| | - Jane A. Skok
- Department of Immunology and Molecular Pathology, University College London, London, United Kingdom
- New York University School of Medicine, New York, New York, United States of America
| | - Patrick Matthias
- Friedrich Miescher Institute for Biomedical Research, Novartis Research Foundation, Basel, Switzerland
- * E-mail:
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Vettermann C, Herrmann K, Albert C, Roth E, Bösl MR, Jäck HM. A unique role for the lambda5 nonimmunoglobulin tail in early B lymphocyte development. THE JOURNAL OF IMMUNOLOGY 2008; 181:3232-42. [PMID: 18713994 DOI: 10.4049/jimmunol.181.5.3232] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Precursor BCR (pre-BCR) signaling governs proliferation and differentiation of pre-B cells during B lymphocyte development. However, it is controversial as to which parts of the pre-BCR, which is composed of Igmu H chain, surrogate L chain (SLC), and Igalpha-Igbeta, are important for signal initiation. Here, we show in transgenic mice that the N-terminal non-Ig-like (unique) tail of the surrogate L chain component lambda5 is critical for enhancing pre-BCR-induced proliferation signals. Pre-BCRs with a mutated lambda5 unique tail are still transported to the cell surface, but they deliver only basal signals that trigger survival and differentiation of pre-B cells. Further, we demonstrate that the positively charged residues of the lambda5 unique tail, which are required for pre-BCR self-oligomerization, can also mediate binding to stroma cell-associated self-Ags, such as heparan sulfate. These findings establish the lambda5 unique tail as a pre-BCR-specific autoreactive signaling motif that could increase the size of the primary Ab repertoire by selectively expanding pre-B cells with functional Igmu H chains.
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Affiliation(s)
- Christian Vettermann
- Division of Molecular Immunology, Department of Internal Medicine III, Nikolaus-Fiebiger-Center for Molecular Medicine, University of Erlangen, Erlangen, Germany
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Lu R. Interferon regulatory factor 4 and 8 in B-cell development. Trends Immunol 2008; 29:487-92. [PMID: 18775669 DOI: 10.1016/j.it.2008.07.006] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2008] [Revised: 07/14/2008] [Accepted: 07/15/2008] [Indexed: 12/27/2022]
Abstract
Interferon regulatory factor 4 (IRF4) and 8 are members of the interferon regulatory factor family of transcription factors and have been shown to be essential for the development and function of T cells, macrophages and dendritic cells. A series of recent studies have further demonstrated critical functions for IRF4 and 8 at several stages of B-cell development including pre-B-cell development, receptor editing, germinal center reaction and plasma cell generation. Collectively, these new studies provide molecular insights into the function of IRF4 and 8 and underscore a requirement for IRF4 and 8 throughout B-cell development. This review focuses on the recent advances on the roles of IRF4 and 8 in B-cell development.
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Affiliation(s)
- Runqing Lu
- Department of Genetics, Cell Biology and Anatomy, University of Nebraska Medical Center, Omaha, NE 68198, USA.
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