51
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Kwak K, Akkaya M, Pierce SK. B cell signaling in context. Nat Immunol 2019; 20:963-969. [PMID: 31285625 DOI: 10.1038/s41590-019-0427-9] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 05/13/2019] [Indexed: 12/11/2022]
Abstract
Over the past several decades, B cell antigen receptor (BCR)-induced signaling pathways have been described in extraordinary molecular detail, mainly from studies of B cell responses to antigens in vitro. BCR signaling has been shown to govern the initiation of transcriptional programs associated with B cell activation and fate decisions, as well as the BCR-dependent processing of antigen and presentation of antigen to T cells. However, although the potential of the BCR to orchestrate B cell behavior was known, there was no clear appreciation of the context in which B cells signal in secondary lymphoid organs in vivo or how that context influences signaling. In this Review, we describe the current view of the cellular consequences of BCR signaling and advances in the understanding of B cell signaling in context in vivo.
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Affiliation(s)
- Kihyuck Kwak
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Munir Akkaya
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA
| | - Susan K Pierce
- Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA.
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52
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Noviski M, Tan C, Huizar J, Vykunta V, Mueller JL, Zikherman J. Optimal Development of Mature B Cells Requires Recognition of Endogenous Antigens. THE JOURNAL OF IMMUNOLOGY 2019; 203:418-428. [PMID: 31167773 DOI: 10.4049/jimmunol.1900175] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 05/11/2019] [Indexed: 12/20/2022]
Abstract
It has long been appreciated that highly autoreactive BCRs are actively removed from the developing B cell repertoire by Ag-dependent receptor editing and deletion. However, there is persistent debate about whether mild autoreactivity is simply tolerated or positively selected into the mature B cell repertoire as well as at what stage, to what extent, under what conditions, and into which compartments this occurs. In this study, we describe two minor, trackable populations of B cells in B1-8i Ig transgenic mice that express the VH186.2 H chain and recognize a common foreign Ag (the hapten 4-hydroxy-3-nitrophenylacetyl) but differ in L chain expression. We use the Nur77-eGFP reporter of BCR signaling to define their reactivity toward endogenous Ags. The less autoreactive of these two populations is strongly counterselected during the development of mature B1a, follicular, and marginal zone B cells. By genetically manipulating the strength of BCR signal transduction via the titration of surface CD45 expression, we demonstrate that this B cell population is not negatively selected but instead displays characteristics of impaired positive selection. We demonstrate that mild self-reactivity improves the developmental fitness of B cell clones in the context of a diverse population of B cells, and positive selection by endogenous Ags shapes the mature B cell repertoire.
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Affiliation(s)
- Mark Noviski
- Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - Corey Tan
- Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - John Huizar
- Howard Hughes Medical Institute Medical Research Fellows Program, University of California, San Francisco, San Francisco, CA 94143; and
| | - Vivasvan Vykunta
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
| | - James L Mueller
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
| | - Julie Zikherman
- Division of Rheumatology, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
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53
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Gold MR, Reth MG. Antigen Receptor Function in the Context of the Nanoscale Organization of the B Cell Membrane. Annu Rev Immunol 2019; 37:97-123. [DOI: 10.1146/annurev-immunol-042718-041704] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The B cell antigen receptor (BCR) plays a central role in the self/nonself selection of B lymphocytes and in their activation by cognate antigen during the clonal selection process. It was long thought that most cell surface receptors, including the BCR, were freely diffusing and randomly distributed. Since the advent of superresolution techniques, it has become clear that the plasma membrane is compartmentalized and highly organized at the nanometer scale. Hence, a complete understanding of the precise conformation and activation mechanism of the BCR must take into account the organization of the B cell plasma membrane. We review here the recent literature on the nanoscale organization of the lymphocyte membrane and discuss how this new information influences our view of the conformational changes that the BCR undergoes during activation.
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Affiliation(s)
- Michael R. Gold
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
- Life Sciences Institute, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Michael G. Reth
- BIOSS Centre for Biological Signaling Studies, University of Freiburg, 79104 Freiburg, Germany
- Department of Molecular Immunology, Institute of Biology III, Faculty of Biology, University of Freiburg, 79108 Freiburg, Germany
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54
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Setz CS, Khadour A, Renna V, Iype J, Gentner E, He X, Datta M, Young M, Nitschke L, Wienands J, Maity PC, Reth M, Jumaa H. Pten controls B-cell responsiveness and germinal center reaction by regulating the expression of IgD BCR. EMBO J 2019; 38:embj.2018100249. [PMID: 31015337 PMCID: PMC6545559 DOI: 10.15252/embj.2018100249] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Revised: 03/22/2019] [Accepted: 03/25/2019] [Indexed: 01/10/2023] Open
Abstract
In contrast to other B‐cell antigen receptor (BCR) classes, the function of IgD BCR on mature B cells remains largely elusive as mature B cells co‐express IgM, which is sufficient for development, survival, and activation of B cells. Here, we show that IgD expression is regulated by the forkhead box transcription factor FoxO1, thereby shifting the responsiveness of mature B cells towards recognition of multivalent antigen. FoxO1 is repressed by phosphoinositide 3‐kinase (PI3K) signaling and requires the lipid phosphatase Pten for its activation. Consequently, Pten‐deficient B cells expressing knock‐ins for BCR heavy and light chain genes are unable to upregulate IgD. Furthermore, in the presence of autoantigen, Pten‐deficient B cells cannot eliminate the autoreactive BCR specificity by secondary light chain gene recombination. Instead, Pten‐deficient B cells downregulate BCR expression and become unresponsive to further BCR‐mediated stimulation. Notably, we observed a delayed germinal center (GC) reaction by IgD‐deficient B cells after immunization with trinitrophenyl‐ovalbumin (TNP‐Ova), a commonly used antigen for T‐cell‐dependent antibody responses. Together, our data suggest that the activation of IgD expression by Pten/FoxO1 results in mature B cells that are selectively responsive to multivalent antigen and are capable of initiating rapid GC reactions and T‐cell‐dependent antibody responses.
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Affiliation(s)
- Corinna S Setz
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Ahmad Khadour
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Valerio Renna
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Joseena Iype
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany.,Department of Molecular Immunology, Biology III, Faculty of Biology, Albert-Ludwigs University of Freiburg, Freiburg, Germany
| | - Eva Gentner
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Xiaocui He
- Department of Molecular Immunology, Biology III, Faculty of Biology, Albert-Ludwigs University of Freiburg, Freiburg, Germany
| | - Moumita Datta
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Marc Young
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Lars Nitschke
- Division of Genetics, Department of Biology, Friedrich Alexander University Erlangen-Nürnberg, Erlangen, Germany
| | - Jürgen Wienands
- Cellular and Molecular Immunology, Georg August University Göttingen, Göttingen, Germany
| | - Palash C Maity
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
| | - Michael Reth
- Department of Molecular Immunology, Biology III, Faculty of Biology, Albert-Ludwigs University of Freiburg, Freiburg, Germany
| | - Hassan Jumaa
- Institute of Immunology, Ulm University Medical Center, Ulm, Germany
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55
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Cyster JG, Allen CDC. B Cell Responses: Cell Interaction Dynamics and Decisions. Cell 2019; 177:524-540. [PMID: 31002794 PMCID: PMC6538279 DOI: 10.1016/j.cell.2019.03.016] [Citation(s) in RCA: 488] [Impact Index Per Article: 97.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 03/05/2019] [Accepted: 03/06/2019] [Indexed: 12/21/2022]
Abstract
B cells and the antibodies they produce have a deeply penetrating influence on human physiology. Here, we review current understanding of how B cell responses are initiated; the different paths to generate short- and long-lived plasma cells, germinal center cells, and memory cells; and how each path impacts antibody diversity, selectivity, and affinity. We discuss how basic research is informing efforts to generate vaccines that induce broadly neutralizing antibodies against viral pathogens, revealing the special features associated with allergen-reactive IgE responses and uncovering the antibody-independent mechanisms by which B cells contribute to health and disease.
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Affiliation(s)
- Jason G Cyster
- Howard Hughes Medical Institute and Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA.
| | - Christopher D C Allen
- Cardiovascular Research Institute, Department of Anatomy, and Sandler Asthma Basic Research Center, University of California, San Francisco, San Francisco, CA 94143, USA.
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56
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Tan C, Mueller JL, Noviski M, Huizar J, Lau D, Dubinin A, Molofsky A, Wilson PC, Zikherman J. Nur77 Links Chronic Antigen Stimulation to B Cell Tolerance by Restricting the Survival of Self-Reactive B Cells in the Periphery. THE JOURNAL OF IMMUNOLOGY 2019; 202:2907-2923. [PMID: 30962292 DOI: 10.4049/jimmunol.1801565] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Accepted: 03/14/2019] [Indexed: 02/01/2023]
Abstract
Nur77 (Nr4a1) belongs to a small family of orphan nuclear receptors that are rapidly induced by BCR stimulation, yet little is known about its function in B cells. We have previously characterized a reporter of Nr4a1 transcription, Nur77-eGFP, in which GFP expression faithfully detects Ag encounter by B cells in vitro and in vivo. In this study, we report that Nur77 expression correlates with the degree of self-reactivity, counterselection, and anergy among individual B cell clones from two distinct BCR transgenic mouse models but is dispensable for all of these tolerance mechanisms. However, we identify a role for Nur77 in restraining survival of self-reactive B cells in the periphery under conditions of competition for a limited supply of the survival factor BAFF. We find that Nur77 deficiency results in the progressive accumulation of self-reactive B cells in the mature repertoire with age and is sufficient to break B cell tolerance in VH3H9 H chain transgenic mice. We thus propose that Nur77 is upregulated in self-reactive B cells in response to chronic Ag stimulation and selectively restricts the survival of these cells, gradually pruning self-reactivity from the mature repertoire to impose a novel layer of peripheral B cell tolerance.
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Affiliation(s)
- Corey Tan
- Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - James L Mueller
- Division of Rheumatology, Rosalind Russell/Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143
| | - Mark Noviski
- Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA 94143
| | - John Huizar
- Howard Hughes Medical Institute Medical Fellows Program, University of California, San Francisco, San Francisco, CA 94143
| | - Denise Lau
- Knapp Center for Lupus and Immunology, Section of Rheumatology, Department of Medicine, The University of Chicago, Chicago, IL 60637.,Committee on Immunology, The University of Chicago, Chicago, IL 60637; and
| | - Alexandra Dubinin
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143
| | - Ari Molofsky
- Department of Laboratory Medicine, University of California, San Francisco, CA 94143
| | - Patrick C Wilson
- Knapp Center for Lupus and Immunology, Section of Rheumatology, Department of Medicine, The University of Chicago, Chicago, IL 60637.,Committee on Immunology, The University of Chicago, Chicago, IL 60637; and
| | - Julie Zikherman
- Division of Rheumatology, Rosalind Russell/Ephraim P. Engleman Rheumatology Research Center, Department of Medicine, University of California, San Francisco, San Francisco, CA 94143;
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57
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Maity PC, Datta M, Nicolò A, Jumaa H. Isotype Specific Assembly of B Cell Antigen Receptors and Synergism With Chemokine Receptor CXCR4. Front Immunol 2019. [PMID: 30619343 DOI: 10.3389/fimmu.2018.02988.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Expression of the membrane-bound form of the immunoglobulin (Ig) as part of the antigen receptor is indispensable for both the development and the effector function of B cells. Among five known isotypes, IgM and IgD are the common B cell antigen receptors (BCRs) that are co-expressed in naïve B cells. Despite having identical antigen specificity and being associated with the same signaling heterodimer Igα/Igβ (CD79a/CD79b), IgM and IgD-BCR isotypes functionally differ from each other in the manner of antigen binding, the formation of isolated nanoclusters and in their interaction with co-receptors such as CD19 and CXCR4 on the plasma membrane. With recent developments in experimental techniques, it is now possible to investigate the nanoscale organization of the BCR and better understand early events of BCR engagement. Interestingly, the cytoskeleton network beneath the membrane controls the BCR isotype-specific organization and its interaction with co-receptors. BCR triggering results in reorganization of the cytoskeleton network, which is further modulated by isotype-specific signals from co-receptors. For instance, IgD-BCR is closely associated with CXCR4 on mature B cells and this close proximity allows CXCR4 to employ the BCR machinery as signaling hub. In this review, we discuss the functional specificity and nanocluster assembly of BCR isotypes and the consequences of cross-talk between CXCR4 and IgD-BCR. Furthermore, given the role of BCR and CXCR4 signaling in the development and survival of leukemic B cells, we discuss the consequences of the cross-talk between CXCR4 and the BCR for controlling the growth of transformed B cells.
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Affiliation(s)
| | - Moumita Datta
- Institute of Immunology, Ulm University, Ulm, Germany
| | | | - Hassan Jumaa
- Institute of Immunology, Ulm University, Ulm, Germany
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58
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Maity PC, Datta M, Nicolò A, Jumaa H. Isotype Specific Assembly of B Cell Antigen Receptors and Synergism With Chemokine Receptor CXCR4. Front Immunol 2019; 9:2988. [PMID: 30619343 PMCID: PMC6305424 DOI: 10.3389/fimmu.2018.02988] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2018] [Accepted: 12/04/2018] [Indexed: 12/20/2022] Open
Abstract
Expression of the membrane-bound form of the immunoglobulin (Ig) as part of the antigen receptor is indispensable for both the development and the effector function of B cells. Among five known isotypes, IgM and IgD are the common B cell antigen receptors (BCRs) that are co-expressed in naïve B cells. Despite having identical antigen specificity and being associated with the same signaling heterodimer Igα/Igβ (CD79a/CD79b), IgM and IgD-BCR isotypes functionally differ from each other in the manner of antigen binding, the formation of isolated nanoclusters and in their interaction with co-receptors such as CD19 and CXCR4 on the plasma membrane. With recent developments in experimental techniques, it is now possible to investigate the nanoscale organization of the BCR and better understand early events of BCR engagement. Interestingly, the cytoskeleton network beneath the membrane controls the BCR isotype-specific organization and its interaction with co-receptors. BCR triggering results in reorganization of the cytoskeleton network, which is further modulated by isotype-specific signals from co-receptors. For instance, IgD-BCR is closely associated with CXCR4 on mature B cells and this close proximity allows CXCR4 to employ the BCR machinery as signaling hub. In this review, we discuss the functional specificity and nanocluster assembly of BCR isotypes and the consequences of cross-talk between CXCR4 and IgD-BCR. Furthermore, given the role of BCR and CXCR4 signaling in the development and survival of leukemic B cells, we discuss the consequences of the cross-talk between CXCR4 and the BCR for controlling the growth of transformed B cells.
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Affiliation(s)
| | - Moumita Datta
- Institute of Immunology, Ulm University, Ulm, Germany
| | | | - Hassan Jumaa
- Institute of Immunology, Ulm University, Ulm, Germany
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59
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Ten Hacken E, Gounari M, Ghia P, Burger JA. The importance of B cell receptor isotypes and stereotypes in chronic lymphocytic leukemia. Leukemia 2018; 33:287-298. [PMID: 30555163 DOI: 10.1038/s41375-018-0303-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 08/29/2018] [Accepted: 10/08/2018] [Indexed: 12/14/2022]
Abstract
B cell receptor (BCR) signaling is a central pathway promoting the survival and proliferation of normal and malignant B cells. Chronic lymphocytic leukemia (CLL) arises from mature B cells, expressing functional BCRs, mainly of immunoglobulin M (IgM) and IgD isotypes. Importantly, 30% of CLL patients express quasi-identical BCRs, the so-called "stereotyped" receptors, indicating the existence of common antigenic determinants, which may drive disease initiation and favor its progression. Although the antigenic specificity of IgM and IgD receptors is identical, there are distinct isotype-specific responses after IgM and IgD triggering. Here, we discuss the most important steps of normal B cell development, and highlight the importance of BCR signaling for CLL pathogenesis, with a focus on differences between IgM and IgD isotype signaling. We also highlight the main characteristics of CLL patient subsets, based on BCR stereotypy, and describe subset-specific BCR function and antigen-binding characteristics. Finally, we outline the key biologic and clinical responses to kinase inhibitor therapy, targeting the BCR-associated Bruton's tyrosine kinase, phosphoinositide-3-kinase, and spleen tyrosine kinase in patients with CLL.
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Affiliation(s)
- Elisa Ten Hacken
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.,Department of Medical Oncology, Dana Farber Cancer Institute, Boston, MA, USA
| | - Maria Gounari
- Institute of Applied Biosciences, Centre for Research and Technology Hellas, Thessaloniki, Greece
| | - Paolo Ghia
- Strategic Research Program on CLL, IRCCS Ospedale San Raffaele and Università Vita-Salute San Raffaele, Milan, Italy
| | - Jan A Burger
- Department of Leukemia, Unit 428, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
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60
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Du SW, Jacobs HM, Arkatkar T, Rawlings DJ, Jackson SW. Integrated B Cell, Toll-like, and BAFF Receptor Signals Promote Autoantibody Production by Transitional B Cells. THE JOURNAL OF IMMUNOLOGY 2018; 201:3258-3268. [PMID: 30373855 DOI: 10.4049/jimmunol.1800393] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 10/01/2018] [Indexed: 12/12/2022]
Abstract
The B cell survival cytokine BAFF has been linked with the pathogenesis of systemic lupus erythematosus (SLE). BAFF binds distinct BAFF-family surface receptors, including the BAFF-R and transmembrane activator and CAML interactor (TACI). Although originally characterized as a negative regulator of B cell activation, TACI signals are critical for class-switched autoantibody (autoAb) production in BAFF transgenic mice. Consistent with this finding, a subset of transitional splenic B cells upregulate surface TACI expression and contribute to BAFF-driven autoAb. In the current study, we interrogated the B cell signals required for transitional B cell TACI expression and Ab production. Surprisingly, despite established roles for dual BCR and TLR signals in autoAb production in SLE, signals downstream of these receptors exerted distinct impacts on transitional B cell TACI expression and autoAb titers. Whereas loss of BCR signals prevented transitional B cell TACI expression and resulted in loss of serum autoAb across all Ig isotypes, lack of TLR signals exerted a more limited impact restricted to autoAb class-switch recombination without altering transitional B cell TACI expression. Finally, in parallel with the protective effect of TACI deletion, loss of BAFF-R signaling also protected against BAFF-driven autoimmunity. Together, these findings highlight how multiple signaling pathways integrate to promote class-switched autoAb production by transitional B cells, events that likely impact the pathogenesis of SLE and other BAFF-dependent autoimmune diseases.
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Affiliation(s)
- Samuel W Du
- Seattle Children's Research Institute, Seattle, WA 98101
| | - Holly M Jacobs
- Seattle Children's Research Institute, Seattle, WA 98101
| | - Tanvi Arkatkar
- Seattle Children's Research Institute, Seattle, WA 98101
| | - David J Rawlings
- Seattle Children's Research Institute, Seattle, WA 98101; .,Department of Immunology, University of Washington School of Medicine, Seattle, WA 98109; and.,Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98105
| | - Shaun W Jackson
- Seattle Children's Research Institute, Seattle, WA 98101; .,Department of Pediatrics, University of Washington School of Medicine, Seattle, WA 98105
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61
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Noviski M, Zikherman J. Control of autoreactive B cells by IgM and IgD B cell receptors: maintaining a fine balance. Curr Opin Immunol 2018; 55:67-74. [PMID: 30292928 DOI: 10.1016/j.coi.2018.09.015] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2018] [Revised: 09/14/2018] [Accepted: 09/17/2018] [Indexed: 12/11/2022]
Abstract
A substantial fraction of mature naïve B cells recognize endogenous antigens, and this autoreactivity must be controlled to prevent autoantibody secretion. Selective downregulation of the IgM BCR on autoreactive B cells has long been appreciated, and recent findings illustrate how this might impose tolerance. The BCR isotype maintained on autoreactive B cells, IgD, is less sensitive to endogenous antigens than IgM. This reduced sensitivity may be conferred by structural properties of IgD and/or differential association with activating and inhibitory co-receptors. Once activated, autoreactive B cells are normally excluded from rapid plasma cell responses, but they can enter the germinal center and lose their autoreactivity through a mutation-selection process termed clonal redemption.
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Affiliation(s)
- Mark Noviski
- Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, CA, 94143, USA
| | - Julie Zikherman
- Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, Division of Rheumatology, Department of Medicine, University of California, San Francisco, CA, 94143, USA.
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62
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Nechvatalova J, Bartol SJW, Chovancova Z, Boon L, Vlkova M, van Zelm MC. Absence of Surface IgD Does Not Impair Naive B Cell Homeostasis or Memory B Cell Formation in IGHD Haploinsufficient Humans. THE JOURNAL OF IMMUNOLOGY 2018; 201:1928-1935. [DOI: 10.4049/jimmunol.1800767] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 07/25/2018] [Indexed: 12/31/2022]
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