1
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McCaleb MR, Miranda AM, Khammash HA, Torres RM, Pelanda R. Regulation of Foxo1 expression is critical for central B cell tolerance and allelic exclusion. Cell Rep 2024; 43:114283. [PMID: 38796853 DOI: 10.1016/j.celrep.2024.114283] [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: 02/01/2024] [Revised: 05/03/2024] [Accepted: 05/10/2024] [Indexed: 05/29/2024] Open
Abstract
Resolving the molecular mechanisms of central B cell tolerance might unveil strategies that prevent autoimmunity. Here, using a mouse model of central B cell tolerance in which Forkhead box protein O1 (Foxo1) is either deleted or over-expressed in B cells, we show that deleting Foxo1 blocks receptor editing, curtails clonal deletion, and decreases CXCR4 expression, allowing high-avidity autoreactive B cells to emigrate to the periphery whereby they mature but remain anergic and short lived. Conversely, expression of degradation-resistant Foxo1 promotes receptor editing in the absence of self-antigen but leads to allelic inclusion. Foxo1 over-expression also restores tolerance in autoreactive B cells harboring active PI3K, revealing opposing roles of Foxo1 and PI3K in B cell selection. Overall, we show that the transcription factor Foxo1 is a major gatekeeper of central B cell tolerance and that PI3K drives positive selection of immature B cells and establishes allelic exclusion by suppressing Foxo1.
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Affiliation(s)
- Megan R McCaleb
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Anjelica M Miranda
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Hadeel A Khammash
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Raul M Torres
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA
| | - Roberta Pelanda
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO 80045, USA.
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2
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Fiske BE, Wemlinger SM, Crute BW, Getahun A. The Src-family kinase Lyn plays a critical role in establishing and maintaining B cell anergy by suppressing PI3K-dependent signaling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.21.595208. [PMID: 38826354 PMCID: PMC11142063 DOI: 10.1101/2024.05.21.595208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Although the Src family kinase (SFK) Lyn is known to be involved in induction and maintenance of peripheral B cell tolerance, the molecular basis of its action in this context remains unclear. This question has been approached using conventional as well as B cell-targeted knockouts of Lyn, with varied conclusions likely confused by collateral loss of Lyn functions in B cell and myeloid cell development and activation. Here we utilized a system in which Lyn gene deletion is tamoxifen inducible and B cell restricted. This system allows acute elimination of Lyn in B cells without off-target effects. This genetic tool was employed in conjunction with immunoglobulin transgenic mice in which peripheral B cells are autoreactive. DNA reactive Ars/A1 B cells require continuous inhibitory signaling, mediated by the inositol phosphatase SHIP-1 and the tyrosine phosphatase SHP-1, to maintain an unresponsive (anergic) state. Here we show that Ars/A1 B cells require Lyn to establish and maintain B cell unresponsiveness. Lyn primarily functions by restricting PI3K-dependent signaling pathways. This Lyn-dependent mechanism complements the impact of reduced mIgM BCR expression to restrict BCR signaling in Ars/A1 B cells. Our findings suggest that a subset of autoreactive B cells requires Lyn to become anergic and that the autoimmunity associated with dysregulated Lyn function may, in part, be due to an inability of these autoreactive B cells to become tolerized.
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3
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Fiske BE, Getahun A. Failed Downregulation of PI3K Signaling Makes Autoreactive B Cells Receptive to Bystander T Cell Help. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2024; 212:1150-1160. [PMID: 38353615 PMCID: PMC10948302 DOI: 10.4049/jimmunol.2300108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 01/16/2024] [Indexed: 02/27/2024]
Abstract
The role of T cell help in autoantibody responses is not well understood. Because tolerance mechanisms govern both T and B cell responses, one might predict that both T cell tolerance and B cell tolerance must be defeated in autoantibody responses requiring T cell help. To define whether autoreactive B cells depend on T cells to generate autoantibody responses, we studied the role of T cells in murine autoantibody responses resulting from acute B cell-specific deletion of regulatory phosphatases. Ars/A1 B cells are DNA reactive and require continuous inhibitory signaling by the tyrosine phosphatase SHP-1 and the inositol phosphatases SHIP-1 and PTEN to maintain unresponsiveness. Acute B cell-restricted deletion of any of these phosphatases results in an autoantibody response. In this study, we show that CD40-CD40L interactions are required to support autoantibody responses of B cells whose anergy has been compromised. If the B cell-intrinsic driver of loss of tolerance is failed negative regulation of PI3K signaling, bystander T cells provide sufficient CD40-mediated signal 2 to support an autoantibody response. However, although autoantibody responses driven by acute B cell-targeted deletion of SHP-1 also require T cells, bystander T cell help does not suffice. These results demonstrate that upregulation of PI3K signaling in autoreactive B cells, recapitulating the effect of multiple autoimmunity risk alleles, promotes autoantibody responses both by increasing B cells' cooperation with noncognate T cell help and by altering BCR signaling. Receptiveness to bystander T cell help enables autoreactive B cells to circumvent the fail-safe of T cell tolerance.
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Affiliation(s)
- Brigita E. Fiske
- Department of Immunology and Microbiology, University of Colorado SOM, Aurora, CO, USA
| | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado SOM, Aurora, CO, USA
- Department of Immunology and Genomic Medicine, National Jewish Health, Denver, CO, USA
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4
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Xu M, Ren J, Jia W, Wang S, Liu Y, Chen X, Shi J, Wang H. Regulation of B-1 cell numbers and B cell-mediated antibody production by Inpp4b. Scand J Immunol 2023; 98:e13309. [PMID: 37389566 DOI: 10.1111/sji.13309] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 06/11/2023] [Accepted: 06/20/2023] [Indexed: 07/01/2023]
Abstract
T and B lymphocytes are crucial players in cellular and humoral immune responses. The development, activation and differentiation of T and B lymphocytes are regulated by the best characterized PI3K-PI (3,4,5) P3-AKT phosphoinositide signalling pathway. As a branch of the phosphoinositide signalling pathway, the lipid phosphatase INPP4B inhibits AKT activation through degrading the phosphoinositide signalling messenger PI (3,4) P2. However, the role of Inpp4b in T and B lymphocytes remains elusive. Here, we reported that Inpp4b was highly expressed in human and murine T- and B-1 lymphocytes. Despite its higher expression in T lymphocytes, neither T cell development and homeostasis nor in vitro T cell activation and CD4+ T cell differentiation were altered upon loss of Inpp4b. Interestingly, combined direct phenotype analysis of Inpp4b conventional knockout mice and adoptive transfer studies revealed that ablation of Inpp4b intrinsically reduced peritoneal B-1 cells rather B-2 cells. Moreover, Inpp4b deficiency led to impaired thymus independent (TI) and thymus dependent (TD) antigens-induced antibody production. Further in vitro analysis revealed that CD40-mediated B cell proliferation was impaired upon ablation of Inpp4b. Our findings reveal that Inpp4b is required in regulating B-1 cell numbers and B cell-mediated antibody production.
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Affiliation(s)
- Meizhen Xu
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
- Clinical Laboratory Center, The First Hospital of Putian City, Putian, China
| | - Jinfeng Ren
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
| | - Wenyu Jia
- Department of dermatology, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Siyu Wang
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
| | - Yuting Liu
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
| | - Xinzhu Chen
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
| | - Jianhong Shi
- Central Laboratory, Hebei Collaborative Innovation Center of Tumor Microecological Metabolism Regulation, Hebei Key Laboratory of Cancer Radiotherapy and Chemotherapy, Affiliated Hospital of Hebei University, Baoding, China
| | - Hui Wang
- Department of Pathogenic Biology and Immunology, Jiangsu Key Laboratory of Immunity and Metabolism, Xuzhou Medical University, Xuzhou, China
- National Experimental Demonstration Center for Basic Medicine Education, Xuzhou Medical University, Xuzhou, China
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5
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Olayinka-Adefemi F, Hou S, Marshall AJ. Dual inhibition of phosphoinositide 3-kinases delta and gamma reduces chronic B cell activation and autoantibody production in a mouse model of lupus. Front Immunol 2023; 14:1115244. [PMID: 37234154 PMCID: PMC10206234 DOI: 10.3389/fimmu.2023.1115244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2022] [Accepted: 04/25/2023] [Indexed: 05/27/2023] Open
Abstract
Phosphoinositide 3-kinase delta (PI3Kδ) plays key roles in normal B cell activation and is chronically activated in malignant B cells. Targeting of PI3Kδ using FDA-approved drugs Idelalisib or Umbralisib has shown efficacy in treatment of multiple B cell malignancies. Duvelisib, an inhibitor targeting both PI3Kδ and PI3Kγ (PI3Kδγi) has also been used for treatment of several leukemias and lymphomas and was suggested to offer potential additional benefits in supressing T cell and inflammatory responses. Transcriptomics analyses indicated that while most B cell subsets predominantly express PI3Kδ, plasma cells upregulate PI3Kγ. We thus assessed whether PI3Kδγi treatment can impact chronic B cell activation in the context of an autoantibody-mediated disease. Using the TAPP1R218LxTAPP2R211L (TAPP KI) mouse model of lupus-like disease driven by dysregulated PI3K pathway activity, we performed 4 week PI3Kδγi treatments and found significant reduction in CD86+ B cells, germinal center B cells, follicular helper T cells and plasma cells in multiple tissues. This treatment also significantly attenuated the abnormally elevated serum levels of IgG isotypes observed in this model. The profile of autoantibodies generated was markedly altered by PI3Kδγi treatment, with significant reductions in IgM and IgG targeting nuclear antigens, matrix proteins and other autoantigens. Kidney pathology was also impacted, with reduced IgG deposition and glomerulonephritis. These results indicate that dual inhibition of PI3Kδ and PI3Kγ can target autoreactive B cells and may have therapeutic benefits in autoantibody-mediated disease.
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6
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Fiske BE, Getahun A. Failed down-regulation of PI3K signaling makes autoreactive B cells receptive to bystander T cell help. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.01.23.525206. [PMID: 36747655 PMCID: PMC9900797 DOI: 10.1101/2023.01.23.525206] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The role of T cell help in autoantibody responses is not well understood. Since tolerance mechanisms govern both T and B cell responses, one might predict that both T cell tolerance and B cell tolerance must be defeated in autoantibody responses requiring T cell help. To define whether autoreactive B cells depend on T cells to generate autoantibody responses, we studied the role of T cells in autoantibody responses resulting from acute cell-specific deletion of regulatory phosphatases. Ars/A1 B cells are DNA-reactive and require continuous inhibitory signaling by the tyrosine phosphatase SHP-1 and the inositol phosphatases SHIP-1 and PTEN to maintain unresponsiveness. Acute B cell-restricted deletion of any of these phosphatases results in an autoantibody response. Here we show that CD40-CD40L interactions are required to support autoantibody responses of B cells whose anergy has been compromised. If the B cell-intrinsic driver of loss of tolerance is failed negative regulation of PI3K signaling, bystander T cells provide sufficient CD40-mediated signal 2 to support an autoantibody response. However, while autoantibody responses driven by acute B cell-targeted deletion of SHP-1 also require T cells, bystander T cell help does not suffice. These results demonstrate that upregulation of PI3K signaling in autoreactive B cells, recapitulating the effect of multiple autoimmunity risk alleles, promotes autoantibody responses both by increasing B cells’ cooperation with non-cognate T cell help, as well as by altering BCR signaling. Receptiveness to bystander T cell help enables autoreactive B cells to circumvent the fail-safe of T cell tolerance. Significance Phosphatase suppression of PI3K signaling is an important mechanism by which peripheral autoreactive B cells are kept in an unresponsive/anergic state. Loss of this suppression, due to genetic alleles that confer risk of autoimmunity, often occurs in autoreactive B cells of individuals who develop autoimmune disease. Here we demonstrate that de-repression of PI3K signaling promotes autoantibody responses of a DNA-reactive B cell clone by relaxing dependence of autoantibody responses on T cell-derived helper signals. These results suggest that impaired regulation of PI3K signaling can promote autoantibody responses in two ways: by restoring antigen receptor signaling and by enabling autoreactive B cells to circumvent restrictions imposed by T cell tolerance mechanisms.
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7
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Harley ITW, Allison K, Scofield RH. Polygenic autoimmune disease risk alleles impacting B cell tolerance act in concert across shared molecular networks in mouse and in humans. Front Immunol 2022; 13:953439. [PMID: 36090990 PMCID: PMC9450536 DOI: 10.3389/fimmu.2022.953439] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2022] [Accepted: 07/19/2022] [Indexed: 11/23/2022] Open
Abstract
Most B cells produced in the bone marrow have some level of autoreactivity. Despite efforts of central tolerance to eliminate these cells, many escape to periphery, where in healthy individuals, they are rendered functionally non-responsive to restimulation through their antigen receptor via a process termed anergy. Broad repertoire autoreactivity may reflect the chances of generating autoreactivity by stochastic use of germline immunoglobulin gene segments or active mechanisms may select autoreactive cells during egress to the naïve peripheral B cell pool. Likewise, it is unclear why in some individuals autoreactive B cell clones become activated and drive pathophysiologic changes in autoimmune diseases. Both of these remain central questions in the study of the immune system(s). In most individuals, autoimmune diseases arise from complex interplay of genetic risk factors and environmental influences. Advances in genome sequencing and increased statistical power from large autoimmune disease cohorts has led to identification of more than 200 autoimmune disease risk loci. It has been observed that autoantibodies are detectable in the serum years to decades prior to the diagnosis of autoimmune disease. Thus, current models hold that genetic defects in the pathways that control autoreactive B cell tolerance set genetic liability thresholds across multiple autoimmune diseases. Despite the fact these seminal concepts were developed in animal (especially murine) models of autoimmune disease, some perceive a disconnect between human risk alleles and those identified in murine models of autoimmune disease. Here, we synthesize the current state of the art in our understanding of human risk alleles in two prototypical autoimmune diseases – systemic lupus erythematosus (SLE) and type 1 diabetes (T1D) along with spontaneous murine disease models. We compare these risk networks to those reported in murine models of these diseases, focusing on pathways relevant to anergy and central tolerance. We highlight some differences between murine and human environmental and genetic factors that may impact autoimmune disease development and expression and may, in turn, explain some of this discrepancy. Finally, we show that there is substantial overlap between the molecular networks that define these disease states across species. Our synthesis and analysis of the current state of the field are consistent with the idea that the same molecular networks are perturbed in murine and human autoimmune disease. Based on these analyses, we anticipate that murine autoimmune disease models will continue to yield novel insights into how best to diagnose, prognose, prevent and treat human autoimmune diseases.
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Affiliation(s)
- Isaac T. W. Harley
- Division of Rheumatology, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
- Human Immunology and Immunotherapy Initiative (HI3), Department of Immunology, University of Colorado School of Medicine, Aurora, CO, United States
- Rheumatology Section, Medicine Service, Rocky Mountain Regional Veterans Affairs Medical Center, Aurora, CO, United States
- *Correspondence: Isaac T. W. Harley,
| | - Kristen Allison
- Division of Rheumatology, Department of Medicine, University of Colorado School of Medicine, Aurora, CO, United States
- Human Immunology and Immunotherapy Initiative (HI3), Department of Immunology, University of Colorado School of Medicine, Aurora, CO, United States
| | - R. Hal Scofield
- Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Arthritis & Clinical Immunology Program, Oklahoma Medical Research Foundation, Oklahoma City, OK, United States
- Medical/Research Service, US Department of Veterans Affairs Medical Center, Oklahoma City, OK, United States
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8
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Wemlinger SM, Parker Harp CR, Yu B, Hardy IR, Seefeldt M, Matsuda J, Mingueneau M, Spilker KA, Cameron TO, Larrick JW, Getahun A, Cambier JC. Preclinical Analysis of Candidate Anti-Human CD79 Therapeutic Antibodies Using a Humanized CD79 Mouse Model. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:1566-1584. [PMID: 35321883 DOI: 10.4049/jimmunol.2101056] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Accepted: 01/18/2022] [Indexed: 11/19/2022]
Abstract
The BCR comprises a membrane-bound Ig that is noncovalently associated with a heterodimer of CD79A and CD79B. While the BCR Ig component functions to sense extracellular Ag, CD79 subunits contain cytoplasmic ITAMs that mediate intracellular propagation of BCR signals critical for B cell development, survival, and Ag-induced activation. CD79 is therefore an attractive target for Ab and chimeric Ag receptor T cell therapies for autoimmunity and B cell neoplasia. Although the mouse is an attractive model for preclinical testing, due to its well-defined immune system, an obstacle is the lack of cross-reactivity of candidate therapeutic anti-human mAbs with mouse CD79. To overcome this problem, we generated knockin mice in which the extracellular Ig-like domains of CD79A and CD79B were replaced with human equivalents. In this study, we describe the generation and characterization of mice expressing chimeric CD79 and report studies that demonstrate their utility in preclinical analysis of anti-human CD79 therapy. We demonstrate that human and mouse CD79 extracellular domains are functionally interchangeable, and that anti-human CD79 lacking Fc region effector function does not cause significant B cell depletion, but induces 1) decreased expression of plasma membrane-associated IgM and IgD, 2) uncoupling of BCR-induced tyrosine phosphorylation and calcium mobilization, and 3) increased expression of PTEN, consistent with the levels observed in anergic B cells. Finally, anti-human CD79 treatment prevents disease development in two mouse models of autoimmunity. We also present evidence that anti-human CD79 treatment may inhibit Ab secretion by terminally differentiated plasmablasts and plasma cells in vitro.
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Affiliation(s)
- Scott M Wemlinger
- Department of Immunology and Microbiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO
| | | | - Bo Yu
- Panorama Research Institute, Sunnyvale, CA
| | | | | | - Jennifer Matsuda
- Department of Biomedical Research, National Jewish Health, Denver, CO; and
| | | | | | | | | | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado Denver, Anschutz Medical Campus, Aurora, CO;
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9
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Getahun A. Role of inhibitory signaling in peripheral B cell tolerance*. Immunol Rev 2022; 307:27-42. [PMID: 35128676 PMCID: PMC8986582 DOI: 10.1111/imr.13070] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2022] [Accepted: 01/17/2022] [Indexed: 12/16/2022]
Abstract
At least 20% of B cells in the periphery expresses an antigen receptor with a degree of self-reactivity. If activated, these autoreactive B cells pose a risk as they can contribute to the development of autoimmune diseases. To prevent their activation, both B cell-intrinsic and extrinsic tolerance mechanisms are in place in healthy individuals. In this review article, I will focus on B cell-intrinsic mechanisms that prevent the activation of autoreactive B cells in the periphery. I will discuss how inhibitory signaling circuits are established in autoreactive B cells, focusing on the Lyn-SHIP-1-SHP-1 axis, how they contribute to peripheral immune tolerance, and how disruptions of these circuits can contribute to the development of autoimmunity.
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Affiliation(s)
- Andrew Getahun
- Department of Immunology and Microbiology University of Colorado SOM Aurora Colorado USA
- Department of Immunology and Genomic Medicine National Jewish Health Denver Colorado USA
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10
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Bier J, Deenick EK. The role of dysregulated PI3Kdelta signaling in human autoimmunity*. Immunol Rev 2022; 307:134-144. [DOI: 10.1111/imr.13067] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 12/27/2021] [Indexed: 12/17/2022]
Affiliation(s)
- Julia Bier
- Garvan Institute of Medical Research Darlinghurst New South Wales Australia
- St Vincent’s Clinical School Faculty of Medicine and Health UNSW Sydney Sydney New South Wales Australia
| | - Elissa K. Deenick
- Garvan Institute of Medical Research Darlinghurst New South Wales Australia
- Faculty of Medicine and Health UNSW Sydney Sydney New South Wales Australia
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11
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Deenick EK, Bier J, Lau A. PI3K Isoforms in B Cells. Curr Top Microbiol Immunol 2022; 436:235-254. [PMID: 36243847 DOI: 10.1007/978-3-031-06566-8_10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Phosphatidylinositol-3-kinases (PI3K) control many aspects of cellular activation and differentiation and play an important role in B cells biology. Three different classes of PI3K have been described, all of which are expressed in B cells. However, it is the class IA PI3Ks, and the p110δ catalytic subunit in particular, which seem to play the most critical role in B cells. Here we discuss the important role that class IA PI3K plays in B cell development, activation and differentiation, as well as examine what is known about the other classes of PI3Ks in B cells.
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Affiliation(s)
- Elissa K Deenick
- Garvan Institute of Medical Research, Darlinghurst, NSW, Australia.
- Faculty of Medicine and Health, UNSW, Sydney, Australia.
| | - Julia Bier
- Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent's Clinical School, Faculty of Medicine and Health, UNSW, Sydney, Australia
| | - Anthony Lau
- Garvan Institute of Medical Research, Darlinghurst, NSW, Australia
- St Vincent's Clinical School, Faculty of Medicine and Health, UNSW, Sydney, Australia
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12
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Tanaka S, Ise W, Baba Y, Kurosaki T. Silencing and activating anergic B cells. Immunol Rev 2021; 307:43-52. [PMID: 34908172 DOI: 10.1111/imr.13053] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2021] [Accepted: 11/30/2021] [Indexed: 02/06/2023]
Abstract
Despite the existence of central tolerance mechanisms, including clonal deletion and receptor editing to eliminate self-reactive B cells, moderately self-reactive cells still survive in the periphery (about 20% of peripheral B cells). These cells normally exist in a functionally silenced state called anergy; thus, anergy has been thought to contribute to tolerance by active-silencing of potentially dangerous B cells. However, a positive rationale for the existence of these anergic B cells has recently been suggested by discoveries that broadly neutralizing antibodies for HIV and influenza virus possess poly- and/or auto-reactivity. Given the conundrum of generating inherent holes in the immune repertoire, retaining weakly self-reactive BCRs on anergic B cells could allow these antibodies to serve as an effective defense against pathogens, particularly in the case of pathogens that mimic forbidden self-epitopes to evade the host immune system. Thus, anergic B cells should be brought into a silenced or activated state, depending on their contexts. Here, we review recent progress in our understanding of how the anergic B cell state is controlled in B cell-intrinsic and B cell-extrinsic ways.
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Affiliation(s)
- Shinya Tanaka
- Division of Immunology and Genome Biology, Department of Molecular Genetics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Wataru Ise
- Team of Host Defense, Center for Infectious Disease Education and Research, Osaka University, Osaka, Japan.,Laboratory of Lymphocyte Differentiation, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan
| | - Yoshihiro Baba
- Division of Immunology and Genome Biology, Department of Molecular Genetics, Medical Institute of Bioregulation, Kyushu University, Fukuoka, Japan
| | - Tomohiro Kurosaki
- Laboratory of Lymphocyte Differentiation, WPI Immunology Frontier Research Center, Osaka University, Osaka, Japan.,Division of Microbiology and Immunology, Center for Infectious Disease Education and Research, Osaka University, Osaka, Japan.,Laboratory of Lymphocyte Differentiation, RIKEN Center for Integrative Medical Sciences (IMS), Yokohama, Japan
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13
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Borbet TC, Hines MJ, Koralov SB. MicroRNA regulation of B cell receptor signaling. Immunol Rev 2021; 304:111-125. [PMID: 34523719 PMCID: PMC8616848 DOI: 10.1111/imr.13024] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/29/2021] [Accepted: 08/31/2021] [Indexed: 12/19/2022]
Abstract
B lymphocytes play a central role in host immune defense. B cell receptor (BCR) signaling regulates survival, proliferation, and differentiation of B lymphocytes. Signaling through the BCR signalosome is a multi-component cascade that is tightly regulated and is important in the coordination of B cell differentiation and function. At different stages of development, B cells that have BCRs recognizing self are eliminated to prevent autoimmunity. microRNAs (miRNAs) are small single-stranded non-coding RNAs that contribute to post-transcriptional regulation of gene expression and have been shown to orchestrate cell fate decisions through the regulation of lineage-specific transcriptional profiles. Studies have identified miRNAs to be crucial for B cell development in the bone marrow and their subsequent population of the peripheral immune system. In this review, we focus on the role of miRNAs in the regulation of BCR signaling as it pertains to B lymphocyte development and function. In particular, we discuss the most recent studies describing the role of miRNAs in the regulation of both early B cell development and peripheral B cell responses and examine the ways by which miRNAs regulate signal downstream of B cell antigen receptor to prevent aberrant activation and autoimmunity.
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Affiliation(s)
- Timothy C. Borbet
- New York University School of Medicine, Department of Pathology, New York, NY 10016
| | - Marcus J. Hines
- New York University School of Medicine, Department of Pathology, New York, NY 10016
| | - Sergei B. Koralov
- New York University School of Medicine, Department of Pathology, New York, NY 10016
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14
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Metabolic determinants of B-cell selection. Biochem Soc Trans 2021; 49:1467-1478. [PMID: 34196360 DOI: 10.1042/bst20201316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Revised: 06/01/2021] [Accepted: 06/07/2021] [Indexed: 11/17/2022]
Abstract
B-cells are antibody-producing cells of the adaptive immune system. Approximately 75% of all newly generated B-cells in the bone marrow are autoreactive and express potentially harmful autoantibodies. To prevent autoimmune disease, the immune system has evolved a powerful mechanism to eliminate autoreactive B-cells, termed negative B-cell selection. While designed to remove autoreactive clones during early B-cell development, our laboratory recently discovered that transformed B-cells in leukemia and lymphoma are also subject to negative selection. Indeed, besides the risk of developing autoimmune disease, B-cells are inherently prone to malignant transformation: to produce high-affinity antibodies, B-cells undergo multiple rounds of somatic immunoglobulin gene recombination and hypermutation. Reflecting high frequencies of DNA-breaks, adaptive immune protection by B-cells comes with a dramatically increased risk of development of leukemia and lymphoma. Of note, B-cells exist under conditions of chronic restriction of energy metabolism. Here we discuss how these metabolic gatekeeper functions during B-cell development provide a common mechanism for the removal of autoreactive and premalignant B-cells to safeguard against both autoimmune diseases and B-cell malignancies.
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15
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Nguyen T, Deenick EK, Tangye SG. Phosphatidylinositol 3-kinase signaling and immune regulation: insights into disease pathogenesis and clinical implications. Expert Rev Clin Immunol 2021; 17:905-914. [PMID: 34157234 DOI: 10.1080/1744666x.2021.1945443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
INTRODUCTION Phosphatidylinositol 3-kinase (PI3K) is a lipid kinase that plays a fundamental role in cell survival, metabolism, proliferation and differentiation. Thus, balanced PI3K signalling is critical for multiple aspects of human health. The discovery that germline variants in genes in the PI3K pathway caused inborn errors of immunity highlighted the non-redundant role of these signalling proteins in the human immune system. The subsequent identification and characterisation of >300 individuals with a novel immune dysregulatory disorder, termed activated PI3K-delta syndrome (APDS), has reinforced the status of PI3K as a key pathway regulating immune function. Studies of APDS have demonstrated that dysregulated PI3K function is disruptive for immune cell development, activation, differentiation, effector function and self-tolerance, which are all important in supporting effective, long-term immune responses. AREAS COVERED In this review, we recount recent findings regarding humans with germline variants in PI3K genes and discuss the underlying cellular and molecular pathologies, with a focus on implications for therapy in APDS patients. EXPERT OPINION Modulating PI3K immune cell signalling by offers opportunities for therapeutic interventions in settings of immunodeficiency, autoimmunity and malignancy, but also highlights potential adverse events that may result from overt pharmacological or intrinsic inhibition of PI3K function.
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Affiliation(s)
- Tina Nguyen
- Immunity & Inflammation Theme, Garvan Institute of Medical Research, Darlinghurst, Australia.,St Vincent's Clinical Clinical School, University of NSW, Kensington, NSW, Australia
| | - Elissa K Deenick
- Immunity & Inflammation Theme, Garvan Institute of Medical Research, Darlinghurst, Australia.,St Vincent's Clinical Clinical School, University of NSW, Kensington, NSW, Australia
| | - Stuart G Tangye
- Immunity & Inflammation Theme, Garvan Institute of Medical Research, Darlinghurst, Australia.,St Vincent's Clinical Clinical School, University of NSW, Kensington, NSW, Australia
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16
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Abstract
B cells are central to the pathogenesis of multiple autoimmune diseases, through antigen presentation, cytokine secretion, and the production of autoantibodies. During development and differentiation, B cells undergo drastic changes in their physiology. It is emerging that these are accompanied by equally significant shifts in metabolic phenotype, which may themselves also drive and enforce the functional properties of the cell. The dysfunction of B cells during autoimmunity is characterised by the breaching of tolerogenic checkpoints, and there is developing evidence that the metabolic state of B cells may contribute to this. Determining the metabolic phenotype of B cells in autoimmunity is an area of active study, and is important because intervention by metabolism-altering therapeutic approaches may represent an attractive treatment target.
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Affiliation(s)
- Iwan G. A. Raza
- Medical Sciences Division, University of Oxford, Oxford, United Kingdom
| | - Alexander J. Clarke
- Kennedy Institute of Rheumatology, University of Oxford, Oxford, United Kingdom
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17
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Adefemi F, Fruman DA, Marshall AJ. A Case for Phosphoinositide 3-Kinase-Targeted Therapy for Infectious Disease. THE JOURNAL OF IMMUNOLOGY 2021; 205:3237-3245. [PMID: 33288538 DOI: 10.4049/jimmunol.2000599] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2020] [Accepted: 08/22/2020] [Indexed: 12/19/2022]
Abstract
PI3Ks activate critical signaling cascades and have multifaceted regulatory functions in the immune system. Loss-of-function and gain-of-function mutations in the PI3Kδ isoform have revealed that this enzyme can substantially impact immune responses to infectious agents and their products. Moreover, reports garnered from decades of infectious disease studies indicate that pharmacologic inhibition of the PI3K pathway could potentially be effective in limiting the growth of certain microbes via modulation of the immune system. In this review, we briefly highlight the development and applications of PI3K inhibitors and summarize data supporting the concept that PI3Kδ inhibitors initially developed for oncology have immune regulatory potential that could be exploited to improve the control of some infectious diseases. This repurposing of existing kinase inhibitors could lay the foundation for alternative infectious disease therapy using available therapeutic agents.
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Affiliation(s)
- Folayemi Adefemi
- Department of Immunology, Rady Faculty of Health Sciences, University of Manitoba, R3E-0T5 Winnipeg, Manitoba, Canada
| | - David A Fruman
- Department of Molecular Biology and Biochemistry, University of California, Irvine, CA 92697; and.,Institute for Immunology, University of California, Irvine, CA 92697
| | - Aaron J Marshall
- Department of Immunology, Rady Faculty of Health Sciences, University of Manitoba, R3E-0T5 Winnipeg, Manitoba, Canada;
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18
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B Cell Aberrance in Lupus: the Ringleader and the Solution. Clin Rev Allergy Immunol 2021; 62:301-323. [PMID: 33534064 DOI: 10.1007/s12016-020-08820-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/02/2020] [Indexed: 12/18/2022]
Abstract
Systemic lupus erythematosus (SLE) is a prototypical autoimmune disease with high heterogeneity but the common characterization of numerous autoantibodies and systemic inflammation which lead to the damage of multiple organs. Aberrance of B cells plays a pivotal role in the immunopathogenesis of SLE via both antibody-dependent and antibody-independent manners. Escape of autoreactive B cells from the central and peripheral tolerance checkpoints, over-activation of B cells and their excessive cytokines release which drive T cells and dendritic cells stimulation, and dysregulated surface molecules, as well as intracellular signal pathways involved in B cell biology, are all contributing to B cell aberrance and participating in the pathogenesis of SLE. Based on that rationale, targeting aberrance of B cells and relevant molecules and pathways is expected to be a promising strategy for lupus control. Multiple approaches targeting B cells through different mechanisms have been attempted, including B-cell depletion via monoclonal antibodies against B-cell-specific molecules, blockade of B-cell survival and activation factors, suppressing T-B crosstalk by interrupting costimulatory molecules and inhibiting intracellular activation signaling cascade by targeting pathway molecules in B cells. Though most attempts ended in failure, the efficacy of B-cell targeting has been encouraged by the FDA approval of belimumab that blocks B cell-activating factor (BAFF) and the recommended use of anti-CD20 as a remedial therapy in refractory lupus. Still, quantities of clinical trials targeting B cells or relevant molecules are ongoing and some of them have displayed promising preliminary results. Additionally, advances in multi-omics studies help deepen our understandings of B cell biology in lupus and may promote the discovery of novel potential therapeutic targets. The combination of real-world data with basic research achievements may pave the road to conquering lupus.
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19
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Sadras T, Chan LN, Xiao G, Müschen M. Metabolic Gatekeepers of Pathological B Cell Activation. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2021; 16:323-349. [DOI: 10.1146/annurev-pathol-061020-050135] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Unlike other cell types, B cells undergo multiple rounds of V(D)J recombination and hypermutation to evolve high-affinity antibodies. Reflecting high frequencies of DNA double-strand breaks, adaptive immune protection by B cells comes with an increased risk of malignant transformation. In addition, the vast majority of newly generated B cells express an autoreactive B cell receptor (BCR). Thus, B cells are under intense selective pressure to remove autoreactive and premalignant clones. Despite stringent negative selection, B cells frequently give rise to autoimmune disease and B cell malignancies. In this review, we discuss mechanisms that we term metabolic gatekeepers to eliminate pathogenic B cell clones on the basis of energy depletion. Chronic activation signals from autoreactive BCRs or transforming oncogenes increase energy demands in autoreactive and premalignant B cells. Thus, metabolic gatekeepers limit energy supply to levels that are insufficient to fuel either a transforming oncogene or hyperactive signaling from an autoreactive BCR.
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Affiliation(s)
- Teresa Sadras
- Center of Molecular and Cellular Oncology, Yale Cancer Center, and Department of Immunobiology, Yale University, New Haven, Connecticut 06520, USA
| | - Lai N. Chan
- Center of Molecular and Cellular Oncology, Yale Cancer Center, and Department of Immunobiology, Yale University, New Haven, Connecticut 06520, USA
| | - Gang Xiao
- Current affiliation: Department of Immunology, Zhejiang University School of Medicine, Hangzhou 310058, China
| | - Markus Müschen
- Center of Molecular and Cellular Oncology, Yale Cancer Center, and Department of Immunobiology, Yale University, New Haven, Connecticut 06520, USA
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20
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Bacalao MA, Satterthwaite AB. Recent Advances in Lupus B Cell Biology: PI3K, IFNγ, and Chromatin. Front Immunol 2021; 11:615673. [PMID: 33519824 PMCID: PMC7841329 DOI: 10.3389/fimmu.2020.615673] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 11/26/2020] [Indexed: 12/18/2022] Open
Abstract
In the autoimmune disease Systemic Lupus Erythematosus (SLE), autoantibodies are formed that promote inflammation and tissue damage. There has been significant interest in understanding the B cell derangements involved in SLE pathogenesis. The past few years have been particularly fruitful in three domains: the role of PI3K signaling in loss of B cell tolerance, the role of IFNγ signaling in the development of autoimmunity, and the characterization of changes in chromatin accessibility in SLE B cells. The PI3K pathway coordinates various downstream signaling molecules involved in B cell development and activation. It is governed by the phosphatases PTEN and SHIP-1. Murine models lacking either of these phosphatases in B cells develop autoimmune disease and exhibit defects in B cell tolerance. Limited studies of human SLE B cells demonstrate reduced expression of PTEN or increased signaling events downstream of PI3K in some patients. IFNγ has long been known to be elevated in both SLE patients and mouse models of lupus. New data suggests that IFNγR expression on B cells is required to develop autoreactive germinal centers (GC) and autoantibodies in murine lupus. Furthermore, IFNγ promotes increased transcription of BCL6, IL-6 and T-bet in B cells, which also promote GC and autoantibody formation. IFNγ also induces epigenetic changes in human B cells. SLE B cells demonstrate significant epigenetic reprogramming, including enhanced chromatin accessibility at transcription factor motifs involved in B cell activation and plasma cell (PC) differentiation as well as alterations in DNA methylation and histone modifications. Histone deacetylase inhibitors limit disease development in murine lupus models, at least in part via their ability to prevent B cell class switching and differentiation into plasma cells. This review will discuss relevant discoveries of the past several years pertaining to these areas of SLE B cell biology.
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Affiliation(s)
- Maria A. Bacalao
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
| | - Anne B. Satterthwaite
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX, United States
- Department of Immunology, University of Texas Southwestern Medical Center, Dallas, TX, United States
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21
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Xiao C, Nemazee D, Gonzalez-Martin A. MicroRNA control of B cell tolerance, autoimmunity and cancer. Semin Cancer Biol 2020; 64:102-107. [PMID: 32522353 DOI: 10.1016/j.semcancer.2019.04.004] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2019] [Accepted: 04/24/2019] [Indexed: 01/14/2023]
Abstract
Since the discovery of the first microRNA (miRNA) in 1993, thousands of miRNAs have been identified in humans and mice and many of them have been shown to control a large variety of cellular processes in different cell types including those composing the immune system. MicroRNAs regulate virtually all aspects of immune cell development, differentiation and function. Studies have shown that these molecules are involved in the maintenance of lymphocyte tolerance and, when dysregulated, promote the development of autoimmune diseases. In this review, we focus on the current knowledge about the roles of miRNAs in B cell tolerance and their contribution to autoimmunity, highlighting additional roles for some of these miRNAs in T cell tolerance. Finally, we will comment on miRNAs that promote both autoimmunity and lymphoma.
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Affiliation(s)
- Changchun Xiao
- State Key Laboratory of Cellular Stress Biology, Innovation Center for Cell Signaling Network, School of Life Sciences, Xiamen University, Xiamen, Fujian, 361005, China
| | - David Nemazee
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, California, USA
| | - Alicia Gonzalez-Martin
- Department of Biochemistry, Universidad Autonoma de Madrid (UAM), Instituto de Investigaciones Biomedicas Alberto Sols (CSIC-UAM), 28029, Madrid, Spain.
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22
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Lau A, Avery DT, Jackson K, Lenthall H, Volpi S, Brigden H, Russell AJ, Bier J, Reed JH, Smart JM, Cole T, Choo S, Gray PE, Berglund LJ, Hsu P, Wong M, O'Sullivan M, Boztug K, Meyts I, Uzel G, Notarangelo LD, Brink R, Goodnow CC, Tangye SG, Deenick EK. Activated PI3Kδ breaches multiple B cell tolerance checkpoints and causes autoantibody production. J Exp Med 2020; 217:132760. [PMID: 31841125 PMCID: PMC7041712 DOI: 10.1084/jem.20191336] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Revised: 09/29/2019] [Accepted: 11/07/2019] [Indexed: 12/17/2022] Open
Abstract
In patients, gain-of-function (GOF) mutations in PIK3CD break tolerance, causing highly penetrant secretion of autoreactive IgM. Mouse models reveal that Pik3cd GOF subverts the response to self-antigen, preventing the induction of anergy and instead stimulating plasmablast and GC formation. Antibody-mediated autoimmune diseases are a major health burden. However, our understanding of how self-reactive B cells escape self-tolerance checkpoints to secrete pathogenic autoantibodies remains incomplete. Here, we demonstrate that patients with monogenic immune dysregulation caused by gain-of-function mutations in PIK3CD, encoding the p110δ catalytic subunit of phosphoinositide 3-kinase (PI3K), have highly penetrant secretion of autoreactive IgM antibodies. In mice with the corresponding heterozygous Pik3cd activating mutation, self-reactive B cells exhibit a cell-autonomous subversion of their response to self-antigen: instead of becoming tolerized and repressed from secreting autoantibody, Pik3cd gain-of-function B cells are activated by self-antigen to form plasmablasts that secrete high titers of germline-encoded IgM autoantibody and hypermutating germinal center B cells. However, within the germinal center, peripheral tolerance was still enforced, and there was selection against B cells with high affinity for self-antigen. These data show that the strength of PI3K signaling is a key regulator of pregerminal center B cell self-tolerance and thus represents a druggable pathway to treat antibody-mediated autoimmunity.
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Affiliation(s)
- Anthony Lau
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St. Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Danielle T Avery
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Katherine Jackson
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Helen Lenthall
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Stefano Volpi
- Clinica Pediatrica e Reumatologia, Centro per le malattie Autoinfiammatorie e Immunodeficienze, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) Istituto Giannina Gaslini and Dipartimento di Neuroscienze, riabilitazione, oftalmologia, genetica e scienze materno-infantili (DINOGMI), Università degli Studi di Genova, Genova, Italy
| | - Henry Brigden
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Amanda J Russell
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
| | - Julia Bier
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St. Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Joanne H Reed
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St. Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia
| | - Joanne M Smart
- Department of Allergy and Immunology, Royal Children's Hospital Melbourne, Victoria, Australia
| | - Theresa Cole
- Department of Allergy and Immunology, Royal Children's Hospital Melbourne, Victoria, Australia
| | - Sharon Choo
- Department of Allergy and Immunology, Royal Children's Hospital Melbourne, Victoria, Australia
| | - Paul E Gray
- School of Women's and Children's Health, UNSW Sydney, Sydney, Australia.,Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia
| | - Lucinda J Berglund
- Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,Immunopathology Department, Westmead Hospital, Westmead, New South Wales, Australia.,Faculty of Medicine, University of Sydney, Sydney, New South Wales, Australia
| | - Peter Hsu
- Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,Children's Hospital at Westmead, New South Wales, Australia
| | - Melanie Wong
- Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,Children's Hospital at Westmead, New South Wales, Australia
| | - Michael O'Sullivan
- Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,Department of Immunology and Allergy, Princess Margaret Hospital, Subiaco, Western Australia, Australia
| | - Kaan Boztug
- Ludwig Boltzmann Institute for Rare and Undiagnosed Diseases, Vienna, Austria.,CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna, Austria.,St. Anna Children's Hospital, Department of Pediatrics and Adolescent Medicine, Medical University of Vienna, Vienna, Austria.,St. Anna Children's Cancer Research Institute (CCRI), Vienna, Austria
| | - Isabelle Meyts
- Department of Immunology and Microbiology, Inborn Errors of Immunity, Department of Pediatrics, University Hospitals Leuven and KU Leuven, Leuven, Belgium
| | - Gulbu Uzel
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Luigi D Notarangelo
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD
| | - Robert Brink
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St. Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia.,Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia
| | - Christopher C Goodnow
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,UNSW Cellular Genomics Futures Institute, UNSW Sydney, Sydney, Australia
| | - Stuart G Tangye
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,St. Vincent's Clinical School, Faculty of Medicine, UNSW Sydney, Sydney, Australia.,Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia
| | - Elissa K Deenick
- Immunity and Inflammatory Diseases, Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia.,Clinical Immunogenomics Research Consortium of Australasia, Sydney, Australia.,Faculty of Medicine, UNSW Sydney, Sydney, Australia
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23
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Agazio A, Cimons J, Shotts KM, Guo K, Santiago ML, Pelanda R, Torres RM. Histone H2A-Reactive B Cells Are Functionally Anergic in Healthy Mice With Potential to Provide Humoral Protection Against HIV-1. Front Immunol 2020; 11:1565. [PMID: 32849530 PMCID: PMC7396680 DOI: 10.3389/fimmu.2020.01565] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/15/2020] [Indexed: 11/13/2022] Open
Abstract
Peripheral tolerance is essential for silencing weakly autoreactive B cells that have escaped central tolerance, but it is unclear why these potentially pathogenic B cells are retained rather than being eliminated entirely. Release from peripheral tolerance restraint can occur under certain circumstances (i.e., strong TLR stimulus), that are present during infection. In this regard, we hypothesized that autoreactive B cells could function as a reserve population that can be activated to contribute to the humoral immune response, particularly with pathogens, such as HIV-1, that exploit immune tolerance to avoid host defense. In this study, we identify a population of autoreactive B cells with the potential to neutralize HIV-1 and experimentally release them from the functional restrictions of peripheral tolerance. We have previously identified murine monoclonal antibodies that displayed autoreactivity against histone H2A and neutralized HIV-1 in vitro. Here, we identify additional H2A-reactive IgM monoclonal antibodies and demonstrate that they are both autoreactive and polyreactive with self and foreign antigens and are able to neutralize multiple clades of tier 2 HIV-1. Flow cytometric analysis of H2A-reactive B cells in naïve wildtype mice revealed that these B cells are present in peripheral B cell populations and we further document that murine H2A-reactive B cells are restrained by peripheral tolerance mechanisms. Specifically, we show endogenous H2A-reactive B cells display increased expression of the inhibitory mediators CD5 and phosphatase and tensin homolog (PTEN) phosphatase and fail to mobilize calcium upon immunoreceptor stimulation; all characterized markers of anergy. Moreover, we show that toll-like receptor stimulation or provision of CD4 T cell help induces the in vitro production of H2A-reactive antibodies, breaking tolerance. Thus, we have identified a novel poly/autoreactive B cell population that has the potential to neutralize HIV-1 but is silenced by immune tolerance.
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Affiliation(s)
- Amanda Agazio
- Department of Immunology & Microbiology, University of Colorado, Aurora, CO, United States
| | - Jennifer Cimons
- Department of Immunology & Microbiology, University of Colorado, Aurora, CO, United States
| | - Kristin M. Shotts
- Department of Immunology & Microbiology, University of Colorado, Aurora, CO, United States
| | - Kejun Guo
- Department of Medicine, Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, CO, United States
| | - Mario L. Santiago
- Department of Medicine, Division of Infectious Diseases, School of Medicine, University of Colorado, Aurora, CO, United States
| | - Roberta Pelanda
- Department of Immunology & Microbiology, University of Colorado, Aurora, CO, United States
| | - Raul M. Torres
- Department of Immunology & Microbiology, University of Colorado, Aurora, CO, United States
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24
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Chen Z, Krinsky A, Woolaver RA, Wang X, Chen SMY, Popolizio V, Xie P, Wang JH. TRAF3 Acts as a Checkpoint of B Cell Receptor Signaling to Control Antibody Class Switch Recombination and Anergy. THE JOURNAL OF IMMUNOLOGY 2020; 205:830-841. [PMID: 32591397 DOI: 10.4049/jimmunol.2000322] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 06/01/2020] [Indexed: 02/06/2023]
Abstract
The BCR recognizes foreign Ags to initiate humoral immunity that needs isotype-switched Abs generated via class switch recombination (CSR); however, stimulating the BCR in the absence of costimulation (e.g., CD40) does not induce CSR; thus, it remains elusive whether and how the BCR induces CSR mechanistically. Autoreactive B cells can maintain anergy via unresponsiveness of their BCRs to self-antigens. However, it remains unknown what molecule(s) restrict BCR signaling strength for licensing BCR-induced CSR and whether deficiency of such molecule(s) disrupts autoreactive B cell anergy and causes B cell-mediated diseases by modulating BCR signaling. In this study, we employ mouse models to show that the BCR's capacity to induce CSR is restrained by B cell-intrinsic checkpoints TRAF3 and TRAF2, whose deletion in B cells enables the BCR to induce CSR in the absence of costimulation. TRAF3 deficiency permits BCR-induced CSR by elevating BCR-proximal signaling intensity. Furthermore, NF-κB2 is required for BCR-induced CSR in TRAF3-deficient B cells but not for CD40-induced or LPS-induced CSR, suggesting that TRAF3 restricts NF-κB2 activation to specifically limit the BCR's ability to induce CSR. TRAF3 deficiency also disrupts autoreactive B cell anergy by elevating calcium influx in response to BCR stimulation, leading to lymphoid organ disorders and autoimmune manifestations. We showed that TRAF3 deficiency-associated autoimmune phenotypes can be rectified by limiting BCR repertoires or attenuating BCR signaling strength. Thus, our studies highlight the importance of TRAF3-mediated restraint on BCR signaling strength for controlling CSR, B cell homeostasis, and B cell-mediated disorders.
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Affiliation(s)
- Zhangguo Chen
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045;
| | - Alexandra Krinsky
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Rachel A Woolaver
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Xiaoguang Wang
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Samantha M Y Chen
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Vince Popolizio
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045
| | - Ping Xie
- Department of Cell Biology and Neuroscience, Rutgers University, Piscataway, NJ 08854; and.,Rutgers Cancer Institute of New Jersey, New Brunswick, NJ 08901
| | - Jing H Wang
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, CO 80045;
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25
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Turner JS, Benet ZL, Grigorova IL. Signals 1, 2 and B cell fate or: Where, when and for how long? Immunol Rev 2020; 296:9-23. [DOI: 10.1111/imr.12865] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2020] [Revised: 04/01/2020] [Accepted: 04/28/2020] [Indexed: 12/14/2022]
Affiliation(s)
- Jackson S. Turner
- Department of Microbiology and Immunology University of Michigan Medical School Ann Arbor MichiganUSA
| | - Zachary L. Benet
- Department of Microbiology and Immunology University of Michigan Medical School Ann Arbor MichiganUSA
| | - Irina L. Grigorova
- Department of Microbiology and Immunology University of Michigan Medical School Ann Arbor MichiganUSA
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26
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Wang Y, Yang Q, Chen X, Tang W, Zhou L, Chen Z, An Y, Zhang Z, Tang X, Zhao X. Phenotypic characterization of patients with activated PI3Kδ syndrome 1 presenting with features of systemic lupus erythematosus. Genes Dis 2020; 8:907-917. [PMID: 34522717 PMCID: PMC8427252 DOI: 10.1016/j.gendis.2020.04.012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 04/22/2020] [Indexed: 10/26/2022] Open
Abstract
Activated phosphoinositide 3-kinase δ syndrome 1 (APDS1) is a primary immunodeficiency disease caused by gain-of-function mutations in PIK3CD. Clinical features of autoimmune disease have been reported in patients with APDS1. In this study, we reported three patients with APDS1 presenting with systemic lupus erythematosus (SLE) phenotype. The clinical manifestations included recurrent respiratory tract infection, lymphoproliferation, Coombs-positive hemolytic anemia, decreased complement fractions, positive antinuclear antibodies, renal complications related to SLE associated diseases, which met the clinical spectrum of APDS1 and the classification criteria of SLE. The immunological phenotype included an inversion in the CD4:CD8 ratio, an increase in both non-circulating Tfh CD4+ memory T and circulating Tfh populations, a low level of recent thymic emigrant T cells, overexpression of CD57 on T cells, and a decrease in B cells with fewer antibody class switch recombination. These phenotypes detected in patients with APDS1 presenting with SLE were resemble that in patients with APDS1 presenting without SLE. Meanwhile, we described the effect of glucocorticoids and rapamycin therapy on patients with APDS1. The phosphorylation of S6 at Ser235/236 was inhibited in patients with APDS1 who underwent glucocorticoids therapy, including two who presented with SLE phenotype. The phosphorylation of AKT at Ser473 and phosphorylation of S6 at Ser235/236 were inhibited in other patients with APDS1 who underwent rapamycin therapy. Here, we showed the coexistence of immunodeficiency and SLE phenotype in APDS1, and the inhibition of rapamycin in activated Akt-mTOR signaling pathway.
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Affiliation(s)
- Yanping Wang
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Qiuyun Yang
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Xuemei Chen
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Wenjing Tang
- Division of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Lina Zhou
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Zhi Chen
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Yunfei An
- Division of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Zhiyong Zhang
- Division of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Xuemei Tang
- Division of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
| | - Xiaodong Zhao
- National Clinical Research Center for Child Health and Disorders (Chongqing), Children's Hospital ofChongqing Medical University, Chongqing, 400014, PR China.,China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Chongqing Key Laboratory of Child Infection and Immunity, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China.,Division of Rheumatology and Immunology, Children's Hospital of Chongqing Medical University, Chongqing, 400014, PR China
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27
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Tan C, Noviski M, Huizar J, Zikherman J. Self-reactivity on a spectrum: A sliding scale of peripheral B cell tolerance. Immunol Rev 2019; 292:37-60. [PMID: 31631352 DOI: 10.1111/imr.12818] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Accepted: 10/02/2019] [Indexed: 12/16/2022]
Abstract
Efficient mechanisms of central tolerance, including receptor editing and deletion, prevent highly self-reactive B cell receptors (BCRs) from populating the periphery. Despite this, modest self-reactivity persists in (and may even be actively selected into) the mature B cell repertoire. In this review, we discuss new insights into mechanisms of peripheral B cell tolerance that restrain mature B cells from mounting inappropriate responses to endogenous antigens, and place recent work into historical context. In particular, we discuss new findings that have arisen from application of a novel in vivo reporter of BCR signaling, Nur77-eGFP, expression of which scales with the degree of self-reactivity in both monoclonal and polyclonal B cell repertoires. We discuss new and historical evidence that self-reactivity is not just tolerated, but actively selected into the peripheral repertoire. We review recent progress in understanding how dual expression of the IgM and IgD BCR isotypes on mature naive follicular B cells tunes responsiveness to endogenous antigen recognition, and discuss how this may be integrated with other features of clonal anergy. Finally, we discuss how expression of Nur77 itself couples chronic antigen stimulation with B cell tolerance.
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Affiliation(s)
- Corey Tan
- Biomedical Sciences (BMS) Graduate Program, University of California, San Francisco, CA, USA
| | - Mark Noviski
- Biomedical Sciences (BMS) Graduate Program, University of California, San Francisco, CA, USA.,Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, University of California, San Francisco, CA, USA
| | - John Huizar
- School of Medicine, HHMI Medical Fellows Program, University of California, San Francisco, CA, USA
| | - Julie Zikherman
- Division of Rheumatology, Department of Medicine, Rosalind Russell and Ephraim P. Engleman Arthritis Research Center, University of California, San Francisco, CA, USA
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28
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Weißenberg SY, Szelinski F, Schrezenmeier E, Stefanski AL, Wiedemann A, Rincon-Arevalo H, Welle A, Jungmann A, Nordström K, Walter J, Imgenberg-Kreuz J, Nordmark G, Rönnblom L, Bachali P, Catalina MD, Grammer AC, Lipsky PE, Lino AC, Dörner T. Identification and Characterization of Post-activated B Cells in Systemic Autoimmune Diseases. Front Immunol 2019; 10:2136. [PMID: 31616406 PMCID: PMC6768969 DOI: 10.3389/fimmu.2019.02136] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Accepted: 08/27/2019] [Indexed: 12/16/2022] Open
Abstract
Autoimmune diseases (AID) such as systemic lupus erythematosus (SLE), primary Sjögren's syndrome (pSS), and rheumatoid arthritis (RA) are chronic inflammatory diseases in which abnormalities of B cell function play a central role. Although it is widely accepted that autoimmune B cells are hyperactive in vivo, a full understanding of their functional status in AID has not been delineated. Here, we present a detailed analysis of the functional capabilities of AID B cells and dissect the mechanisms underlying altered B cell function. Upon BCR activation, decreased spleen tyrosine kinase (Syk) and Bruton's tyrosine kinase (Btk) phosphorylation was noted in AID memory B cells combined with constitutive co-localization of CD22 and protein tyrosine phosphatase (PTP) non-receptor type 6 (SHP-1) along with hyporesponsiveness to TLR9 signaling, a Syk-dependent response. Similar BCR hyporesponsiveness was also noted specifically in SLE CD27− B cells together with increased PTP activities and increased transcripts for PTPN2, PTPN11, PTPN22, PTPRC, and PTPRO in SLE B cells. Additional studies revealed that repetitive BCR stimulation of normal B cells can induce BCR hyporesponsiveness and that tissue-resident memory B cells from AID patients also exhibited decreased responsiveness immediately ex vivo, suggesting that the hyporesponsive status can be acquired by repeated exposure to autoantigen(s) in vivo. Functional studies to overcome B cell hyporesponsiveness revealed that CD40 co-stimulation increased BCR signaling, induced proliferation, and downregulated PTP expression (PTPN2, PTPN22, and receptor-type PTPs). The data support the conclusion that hyporesponsiveness of AID and especially SLE B cells results from chronic in vivo stimulation through the BCR without T cell help mediated by CD40–CD154 interaction and is manifested by decreased phosphorylation of BCR-related proximal signaling molecules and increased PTPs. The hyporesponsiveness of AID B cells is similar to a form of functional anergy.
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Affiliation(s)
- Sarah Y Weißenberg
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany.,German Rheumatism Research Center Berlin (DRFZ), Berlin, Germany
| | - Franziska Szelinski
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany.,German Rheumatism Research Center Berlin (DRFZ), Berlin, Germany
| | - Eva Schrezenmeier
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany
| | - Ana-Luisa Stefanski
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany
| | - Annika Wiedemann
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany
| | - Hector Rincon-Arevalo
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany.,German Rheumatism Research Center Berlin (DRFZ), Berlin, Germany.,Grupo de Inmunología Celular e Inmunogenética, Facultad de Medicina, Instituto de Investigaciones Médicas, Universidad de Antioquia UdeA, Medellín, Colombia
| | - Anna Welle
- Department of Genetics and Epigenetics, Saarland University, Saarbrücken, Germany
| | - Annemarie Jungmann
- Department of Genetics and Epigenetics, Saarland University, Saarbrücken, Germany
| | - Karl Nordström
- Department of Genetics and Epigenetics, Saarland University, Saarbrücken, Germany
| | - Jörn Walter
- Department of Genetics and Epigenetics, Saarland University, Saarbrücken, Germany
| | - Juliana Imgenberg-Kreuz
- Department of Medical Sciences, Rheumatology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Gunnel Nordmark
- Department of Medical Sciences, Rheumatology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Lars Rönnblom
- Department of Medical Sciences, Rheumatology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | | | | | - Amrie C Grammer
- RILITE Research Institute, Charlottesville, VA, United States
| | - Peter E Lipsky
- RILITE Research Institute, Charlottesville, VA, United States
| | - Andreia C Lino
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany.,German Rheumatism Research Center Berlin (DRFZ), Berlin, Germany
| | - Thomas Dörner
- Department of Rheumatology and Clinical Immunology, Charité University Medicine Berlin, Berlin, Germany.,German Rheumatism Research Center Berlin (DRFZ), Berlin, Germany
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29
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Franks SE, Getahun A, Cambier JC. A Precision B Cell-Targeted Therapeutic Approach to Autoimmunity Caused by Phosphatidylinositol 3-Kinase Pathway Dysregulation. THE JOURNAL OF IMMUNOLOGY 2019; 202:3381-3393. [PMID: 31076529 DOI: 10.4049/jimmunol.1801394] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2018] [Accepted: 04/08/2019] [Indexed: 12/17/2022]
Abstract
The inositol lipid phosphatases PTEN and SHIP-1 play a crucial role in maintaining B cell anergy and are reduced in expression in B cells from systemic lupus erythematosus and type 1 diabetes patients, consequent to aberrant regulation by miRNA-7 and 155. With an eye toward eventual use in precision medicine therapeutic approaches in autoimmunity, we explored the ability of p110δ inhibition to compensate for PI3K pathway dysregulation in mouse models of autoimmunity. Low dosages of the p110δ inhibitor idelalisib, which spare the ability to mount an immune response to exogenous immunogens, are able to block the development of autoimmunity driven by compromised PI3K pathway regulation resultant from acutely induced B cell-targeted haploinsufficiency of PTEN and SHIP-1. These conditions do not block autoimmunity driven by B cell loss of the regulatory tyrosine phosphatase SHP-1. Finally, we show that B cells in NOD mice express reduced PTEN, and low-dosage p110δ inhibitor therapy blocks disease progression in this model of type 1 diabetes. These studies may aid in the development of precision treatments that act by enforcing PI3K pathway regulation in patients carrying specific risk alleles.
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Affiliation(s)
- S Elizabeth Franks
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045
| | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045
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30
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31
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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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32
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Greaves SA, Peterson JN, Strauch P, Torres RM, Pelanda R. Active PI3K abrogates central tolerance in high-avidity autoreactive B cells. J Exp Med 2019; 216:1135-1153. [PMID: 30948496 PMCID: PMC6504226 DOI: 10.1084/jem.20181652] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 01/23/2019] [Accepted: 03/22/2019] [Indexed: 01/02/2023] Open
Abstract
High-avidity autoreactive B cells are typically removed by central tolerance mechanisms in the bone marrow. Greaves et al. demonstrate that B cell–intrinsic expression of active PI3Kα prevents central tolerance and effectively promotes differentiation and activation of high-avidity autoreactive B cells in the periphery. Autoreactive B cells that bind self-antigen with high avidity in the bone marrow undergo mechanisms of central tolerance that prevent their entry into the peripheral B cell population. These mechanisms are breached in many autoimmune patients, increasing their risk of B cell–mediated autoimmune diseases. Resolving the molecular pathways that can break central B cell tolerance could therefore provide avenues to diminish autoimmunity. Here, we show that B cell–intrinsic expression of a constitutively active form of PI3K-P110α by high-avidity autoreactive B cells of mice completely abrogates central B cell tolerance and further promotes these cells to escape from the bone marrow, differentiate in peripheral tissue, and undergo activation in response to self-antigen. Upon stimulation with T cell help factors, these B cells secrete antibodies in vitro but remain unable to secrete autoantibodies in vivo. Overall, our data demonstrate that activation of the PI3K pathway leads high-avidity autoreactive B cells to breach central, but not late, stages of peripheral tolerance.
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Affiliation(s)
- Sarah A Greaves
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO
| | - Jacob N Peterson
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO
| | - Pamela Strauch
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO
| | - Raul M Torres
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO.,Department of Biomedical Research, National Jewish Health, Denver, CO
| | - Roberta Pelanda
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Anschutz Medical Campus, Aurora, CO .,Department of Biomedical Research, National Jewish Health, Denver, CO
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33
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Tangye SG, Bier J, Lau A, Nguyen T, Uzel G, Deenick EK. Immune Dysregulation and Disease Pathogenesis due to Activating Mutations in PIK3CD-the Goldilocks' Effect. J Clin Immunol 2019; 39:148-158. [PMID: 30911953 DOI: 10.1007/s10875-019-00612-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2019] [Accepted: 03/12/2019] [Indexed: 12/12/2022]
Abstract
"This porridge is too hot!" she exclaimed. So, she tasted the porridge from the second bowl. "This porridge is too cold," she said. So, she tasted the last bowl of porridge. "Ahhh, this porridge is just right," she said happily and she ate it all up. While this describes the adventures of Goldilocks in the classic fairytale "The Story of Goldilocks and the Three Bears," it is an ideal analogy for the need for balanced signaling mediated by phosphatidylinositol-3-kinase (PI3K), a key signaling hub in immune cells. Either too little or too much PI3K activity is deleterious, even pathogenic-it needs to be "just right"! This has been elegantly demonstrated by the identification of inborn errors of immunity in key components of the PI3K pathway, and the impact of these mutations on immune regulation. Detailed analyses of patients with germline activating mutations in PIK3CD, as well as the parallel generation of novel murine models of this disease, have shed substantial light on the role of PI3K in lymphocyte development and differentiation, and mechanisms of disease pathogenesis resulting not only from PIK3CD mutations but genetic lesions in other components of the PI3K pathway. Furthermore, by being able to pharmacologically target PI3K, these monogenic conditions have provided opportunities for the implementation of precision medicine as a therapy, as well as to gain further insight into the consequences of modulating the PI3K pathway in clinical settings.
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Affiliation(s)
- Stuart G Tangye
- Immunology, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia. .,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia.
| | - Julia Bier
- Immunology, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia
| | - Anthony Lau
- Immunology, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia
| | - Tina Nguyen
- Immunology, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia
| | - Gulbu Uzel
- Laboratory of Clinical Immunology and Microbiology, National Institutes of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Elissa K Deenick
- Immunology, Garvan Institute of Medical Research, 384 Victoria St, Darlinghurst, NSW, 2010, Australia.,St Vincent's Clinical School, University of New South Wales, Darlinghurst, Australia
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34
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Müschen M. Metabolic gatekeepers to safeguard against autoimmunity and oncogenic B cell transformation. Nat Rev Immunol 2019; 19:337-348. [DOI: 10.1038/s41577-019-0154-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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35
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Single Cell Profiling Reveals PTEN Overexpression in Influenza-Specific B cells in Aging HIV-infected individuals on Anti-retroviral Therapy. Sci Rep 2019; 9:2482. [PMID: 30792481 PMCID: PMC6385500 DOI: 10.1038/s41598-019-38906-y] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2018] [Accepted: 01/04/2019] [Indexed: 11/09/2022] Open
Abstract
Memory B cells (MBC) respond to secondary antigen challenge to protect against infection and to boost immunity following vaccinations. Despite effective treatment, chronic HIV infection disturbs MBCs by reducing numbers and altering functionality due to hyper-activation and increased apoptosis leading to suboptimal antibody responses against common infectious agents. We used single cell gene expression analysis to evaluate antigen-specific memory B cells in peripheral blood of virally-suppressed HIV-infected individuals and healthy controls stratified by serum H1N1 antibody response 3 weeks post-administration of the seasonal trivalent inactivated influenza vaccine. We used a fluorescent probe to isolate influenza H1N1-specific B cells and a multiplexed and targeted RT-PCR approach to measure expression levels of 96 genes involved in B cell activation and function. Gene profiling revealed a 4-gene predictive signature containing the phosphoinositide-3 kinase (PI3K) inhibitor, PTEN, for identifying antigen-specific MBC from HIV-infected individuals compared to healthy controls. Gene co-expression analysis showed that in addition to overexpression of PTEN, there was increased co-expression of type I interferon-associated genes with PTEN on single cell level in HIV compared to controls. This study highlights the persistent defects in MBC from HIV-infected individuals and points to the PI3K signaling pathway as a target for potential immune intervention.
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36
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Smith MJ, Ford BR, Rihanek M, Coleman BM, Getahun A, Sarapura VD, Gottlieb PA, Cambier JC. Elevated PTEN expression maintains anergy in human B cells and reveals unexpectedly high repertoire autoreactivity. JCI Insight 2019; 4:e123384. [PMID: 30728334 PMCID: PMC6413793 DOI: 10.1172/jci.insight.123384] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Accepted: 01/09/2019] [Indexed: 11/17/2022] Open
Abstract
It has been reported that 2.5%-30% of human peripheral CD27- B cells are autoreactive and anergic based on unresponsiveness to antigen receptor (BCR) stimulation and autoreactivity of cloned and expressed BCR. The molecular mechanisms that maintain this unresponsiveness are unknown. Here, we showed that in humans anergy is maintained by elevated expression of PTEN, a phosphatidylinositol 3,4,5P-3-phosphatase. Upregulation of PTEN was associated with reduced expression of microRNAs that control its expression. Pharmacologic inhibition of PTEN lead to significant restoration of responsiveness. Consistent with a role in conferring risk of autoimmunity, B cells from type 1 diabetics and autoimmune thyroid disease patients expressed reduced PTEN. Unexpectedly, in healthy individuals PTEN expression was elevated in on average 40% of CD27- B cells, with levels gradually decreasing as IgM levels increase. Our findings suggest that a much higher proportion of the peripheral repertoire is autoreactive than previously thought and that B cells upregulate PTEN in a manner that is proportional to the recognition of autoantigens of increasing avidity, thus tuning BCR signaling to prevent development of autoimmunity while providing a reservoir of cells that can be readily activated to respond when needed.
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Affiliation(s)
- Mia J. Smith
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, Colorado, USA
| | - B. Rhodes Ford
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Marynette Rihanek
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Brianne M. Coleman
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Virginia D. Sarapura
- Division of Endocrinology, Metabolism, and Diabetes, University of Colorado Health Sciences Center, Aurora, Colorado, USA
| | - Peter A. Gottlieb
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - John C. Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
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37
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Guo R, Li J, Gu Y, Li Y, Li S, Gao X, Zhu Z, Tu P. GYF-21, an epoxide 2‑(2‑phenethyl)‑chromone derivative, suppresses dysfunction of B cells mainly via inhibiting BAFF activated signaling pathways. Int Immunopharmacol 2019; 67:473-482. [DOI: 10.1016/j.intimp.2018.12.048] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 12/20/2018] [Accepted: 12/21/2018] [Indexed: 10/27/2022]
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38
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Smith MJ, Hinman RM, Getahun A, Kim S, Packard TA, Cambier JC. Silencing of high-affinity insulin-reactive B lymphocytes by anergy and impact of the NOD genetic background in mice. Diabetologia 2018; 61:2621-2632. [PMID: 30255377 PMCID: PMC6219930 DOI: 10.1007/s00125-018-4730-z] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2018] [Accepted: 08/16/2018] [Indexed: 12/22/2022]
Abstract
AIMS/HYPOTHESIS Previous studies have demonstrated that high-affinity insulin-binding B cells (IBCs) silenced by anergy in healthy humans lose their anergy in islet autoantibody-positive individuals with recent-onset type 1 diabetes, and in autoantibody-negative first-degree relatives carrying certain risk alleles. Here we explore the hypothesis that IBCs are found in the immune periphery of disease-resistant C57BL/6-H2g7 mice, where, as in healthy humans, they are anergic, but that in disease-prone genetic backgrounds (NOD) they become activated and migrate to the pancreas and pancreatic lymph nodes, where they participate in the development of type 1 diabetes. METHODS We compared the status of high-affinity IBCs in disease-resistant VH125.C57BL/6-H2g7 and disease-prone VH125.NOD mice. RESULTS Consistent with findings in healthy humans, high-affinity IBCs reach the periphery in disease-resistant mice and are anergic, as indicated by a reduced expression of membrane IgM, unresponsiveness to antigen and failure to become activated or accumulate in the pancreatic lymph nodes or pancreas. In NOD mice, high-affinity IBCs reach the periphery early in life and increase in number prior to the onset of hyperglycaemia. These cells are not anergic; they become activated, produce autoantibodies and accumulate in the pancreas and pancreatic lymph nodes prior to disease development. CONCLUSIONS/INTERPRETATION These findings are consistent with genetic determination of the escape of high-affinity IBCs from anergy and their early contribution to the development of type 1 diabetes.
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Affiliation(s)
- Mia J Smith
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Rochelle M Hinman
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA
| | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA
| | - Soojin Kim
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA
| | - Thomas A Packard
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, P18-8100, RC1 North, 12800 East 19th Avenue, Aurora, CO, 80045-2537, USA.
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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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Jayachandran N, Mejia EM, Sheikholeslami K, Sher AA, Hou S, Hatch GM, Marshall AJ. TAPP Adaptors Control B Cell Metabolism by Modulating the Phosphatidylinositol 3-Kinase Signaling Pathway: A Novel Regulatory Circuit Preventing Autoimmunity. THE JOURNAL OF IMMUNOLOGY 2018; 201:406-416. [DOI: 10.4049/jimmunol.1701440] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Accepted: 05/10/2018] [Indexed: 01/24/2023]
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Franks SE, Cambier JC. Putting on the Brakes: Regulatory Kinases and Phosphatases Maintaining B Cell Anergy. Front Immunol 2018; 9:665. [PMID: 29681901 PMCID: PMC5897502 DOI: 10.3389/fimmu.2018.00665] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 03/19/2018] [Indexed: 12/21/2022] Open
Abstract
B cell antigen receptor (BCR) signaling is a tightly regulated process governed by both positive and negative mediators/regulators to ensure appropriate responses to exogenous and autologous antigens. Upon naïve B cell recognition of antigen CD79 [the immunoreceptor tyrosine-based activation motif (ITAM)-containing signaling subunit of the BCR] is phosphorylated and recruits Src and Syk family kinases that then phosphorylate proximal intermediaries linked to downstream activating signaling circuitry. This plasma membrane localized signalosome activates PI3K leading to generation of PIP3 critical for membrane localization and activation of plecktrin homology domain-containing effectors. Conversely, in anergic B cells, chronic antigen stimulation drives biased monophosphorylation of CD79 ITAMs leading to recruitment of Lyn, but not Syk, which docks only to bi-phosphorylated ITAMS. In this context, Lyn appears to function primarily as a driver of inhibitory signaling pathways promoting the inhibition of the PI3K pathway by inositol phosphatases, SHIP-1 and PTEN, which hydrolyze PIP3 to PIP2. Lyn may also exert negative regulation of signaling through recruitment of SHP-1, a tyrosine phosphatase that dephosphorylates activating signaling molecules. Alleles of genes that encode or regulate expression of components of this axis, including SHIP-1, SHP-1, Csk/PTPn22, and Lyn, have been shown to confer risk of autoimmunity. This review will discuss functional interplay of components of this pathway and the impact of risk alleles on its function.
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Affiliation(s)
- S Elizabeth Franks
- Department of Immunology and Microbiology, University of Colorado Denver School of Medicine, Aurora, CO, United States
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado Denver School of Medicine, Aurora, CO, United States
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Smith MJ, Rihanek M, Wasserfall C, Mathews CE, Atkinson MA, Gottlieb PA, Cambier JC. Loss of B-Cell Anergy in Type 1 Diabetes Is Associated With High-Risk HLA and Non-HLA Disease Susceptibility Alleles. Diabetes 2018; 67:697-703. [PMID: 29343548 PMCID: PMC5860860 DOI: 10.2337/db17-0937] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Accepted: 01/12/2018] [Indexed: 12/18/2022]
Abstract
Although B cells reactive with islet autoantigens are silenced by tolerance mechanisms in healthy individuals, they can become activated and contribute to the development of type 1 diabetes. We previously demonstrated that high-affinity insulin-binding B cells (IBCs) occur exclusively in the anergic (BND) compartment in peripheral blood of healthy subjects. Consistent with their activation early in disease development, high-affinity IBCs are absent from the BND compartment of some first-degree relatives (FDRs) as well as all patients with autoantibody-positive prediabetes and new-onset type 1 diabetes, a time when they are found in pancreatic islets. Loss of BND IBCs is associated with a loss of the entire BND B-cell compartment consistent with provocation by an environmental trigger or predisposing genetic factors. To investigate potential mechanisms operative in subversion of B-cell tolerance, we explored associations between HLA and non-HLA type 1 diabetes-associated risk allele genotypes and loss of BNDs in FDRs. We found that high-risk HLA alleles and a subset of non-HLA risk alleles (i.e., PTPN2 [rs1893217], INS [rs689], and IKZF3 [rs2872507]), relevant to B- and T-cell development and function are associated with loss of anergy. Hence, the results suggest a role for risk-conferring alleles in perturbation of B-cell anergy during development of type 1 diabetes.
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Affiliation(s)
- Mia J Smith
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO
| | - Marynette Rihanek
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - Clive Wasserfall
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL
| | - Clayton E Mathews
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL
| | - Mark A Atkinson
- Department of Pathology, Immunology, and Laboratory Medicine, University of Florida College of Medicine, Gainesville, FL
- Department of Pediatrics, University of Florida College of Medicine, Gainesville, FL
| | - Peter A Gottlieb
- Barbara Davis Center for Childhood Diabetes, University of Colorado School of Medicine, Aurora, CO
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO
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Vangapandu HV, Havranek O, Ayres ML, Kaipparettu BA, Balakrishnan K, Wierda WG, Keating MJ, Davis RE, Stellrecht CM, Gandhi V. B-cell Receptor Signaling Regulates Metabolism in Chronic Lymphocytic Leukemia. Mol Cancer Res 2017; 15:1692-1703. [PMID: 28835371 PMCID: PMC5714317 DOI: 10.1158/1541-7786.mcr-17-0026] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 06/16/2017] [Accepted: 08/15/2017] [Indexed: 11/16/2022]
Abstract
Peripheral blood chronic lymphocytic leukemia (CLL) cells are quiescent but have active transcription and translation processes, suggesting that these lymphocytes are metabolically active. Based on this premise, the metabolic phenotype of CLL lymphocytes was investigated by evaluating the two intracellular ATP-generating pathways. Metabolic flux was assessed by measuring glycolysis as extracellular acidification rate (ECAR) and mitochondrial oxidative phosphorylation as oxygen consumption rate (OCR) and then correlated with prognostic factors. Further, the impact of B-cell receptor signaling (BCR) on metabolism was determined by genetic ablation and pharmacological inhibitors. Compared with proliferative B-cell lines, metabolic fluxes of oxygen and lactate were low in CLL cells. ECAR was consistently low, but OCR varied considerably in human patient samples (n = 45). Higher OCR was associated with poor prognostic factors such as ZAP 70 positivity, unmutated IGHV, high β2M levels, and higher Rai stage. Consistent with the association of ZAP 70 and IGHV unmutated status with active BCR signaling, genetic ablation of BCR mitigated OCR in malignant B cells. Similarly, knocking out PI3Kδ, a critical component of the BCR pathway, decreased OCR and ECAR. In concert, PI3K pathway inhibitors dramatically reduced OCR and ECAR. In harmony with a decline in metabolic activity, the ribonucleotide pools in CLL cells were reduced with duvelisib treatment. Collectively, these data demonstrate that CLL metabolism, especially OCR, is linked to prognostic factors and is curbed by BCR and PI3K pathway inhibition.Implications: This study identifies a relationship between oxidative phosphorylation in CLL and prognostic factors providing a rationale to therapeutically target these processes. Mol Cancer Res; 15(12); 1692-703. ©2017 AACR.
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MESH Headings
- Adenosine Triphosphate/genetics
- Adenosine Triphosphate/metabolism
- Apoptosis/genetics
- Cell Line, Tumor
- Cell Proliferation/genetics
- Class I Phosphatidylinositol 3-Kinases/genetics
- Glycolysis/genetics
- Humans
- Leukemia, Lymphocytic, Chronic, B-Cell/genetics
- Leukemia, Lymphocytic, Chronic, B-Cell/metabolism
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Metabolic Networks and Pathways/genetics
- Oxidative Phosphorylation
- Oxygen Consumption/genetics
- Prognosis
- Receptors, Antigen, B-Cell/genetics
- ZAP-70 Protein-Tyrosine Kinase/genetics
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Affiliation(s)
- Hima V Vangapandu
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Ondrej Havranek
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Mary L Ayres
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | | | - Kumudha Balakrishnan
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
| | - William G Wierda
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Michael J Keating
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - R Eric Davis
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
- Department of Lymphoma/Myeloma, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Christine M Stellrecht
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
| | - Varsha Gandhi
- Department of Experimental Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
- MD Anderson Cancer Center UT Health Graduate School of Biomedical Sciences, Houston, Texas
- Department of Leukemia, The University of Texas MD Anderson Cancer Center, Houston, Texas
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44
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Molfino A, Alessandri F, Mosillo P, Dell'Utri D, Farcomeni A, Amabile MI, Laviano A. PTEN expression and its association with glucose control and calorie supplementation in critically ill patients. Clin Nutr 2017; 37:2186-2190. [PMID: 29154111 DOI: 10.1016/j.clnu.2017.10.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Revised: 08/07/2017] [Accepted: 10/28/2017] [Indexed: 11/28/2022]
Abstract
BACKGROUND & AIM Phosphatase and tensin homologue (PTEN) reduces insulin sensitivity. Since critically ill patients present insulin resistance, we aimed at assessing the role of PTEN expression on glucose homeostasis and clinical outcome in patients admitted to an intensive care unit (ICU) and receiving artificial nutrition. METHODS Observational, single-center study conducted in one ICU in Rome, Italy on adult patients hospitalized for trauma. Plasma glucose levels and its variability were recorded in patients receiving artificial nutrition. PTEN expression was measured by western blotting analysis and the associations between PTEN, plasma glucose levels and variability, and calories administered were investigated. Parametric and non-parametric tests were used, as appropriate. RESULTS Twenty consecutive patients (13 men and 7 women, mean age of 37.3 ± 12.7 years) were studied. No correlation between plasma glucose and PTEN was documented (r = -0.15, P = 0.55), neither between glycemic variability and PTEN expression (r = -0.00, P = 0.99). However, total kcal/day administered and PTEN expression significantly correlated (r = 0.56, P = 0.01). Also, patients with PTEN levels below the median received less kcal/day than those with PTEN above the median (P = 0.048). This association was more pronounced when normalized per body weight (P = 0.03) and after adjusting for the average of insulin daily administered (P = 0.02). CONCLUSIONS PTEN expression might significantly contribute to glucose homeostasis and disposal in critically ill patients receiving artificial nutrition. Larger samples are necessary to confirm our observation. CLINICAL TRIAL REGISTRY NUMBER NCT01796847 (www.clinicaltrials.gov) submitted on February 11, 2013.
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Affiliation(s)
- Alessio Molfino
- Department of Clinical Medicine, Sapienza University of Rome, Italy.
| | - Francesco Alessandri
- Department of Cardiovascular, Respiratory, Nephrology, Anesthesiology and Geriatric Sciences, Sapienza University of Rome, Italy.
| | - Paola Mosillo
- Department of Physiology and Pharmacology "Vittorio Erspamer", Sapienza University of Rome, Italy.
| | - Donatella Dell'Utri
- Department of Cardiovascular, Respiratory, Nephrology, Anesthesiology and Geriatric Sciences, Sapienza University of Rome, Italy.
| | - Alessio Farcomeni
- Department of Public Health and Infectious Diseases, Sapienza University of Rome, Italy.
| | - Maria Ida Amabile
- Department of Clinical Medicine, Sapienza University of Rome, Italy.
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Chang NH, Manion KP, Loh C, Pau E, Baglaenko Y, Wither JE. Multiple tolerance defects contribute to the breach of B cell tolerance in New Zealand Black chromosome 1 congenic mice. PLoS One 2017. [PMID: 28628673 PMCID: PMC5476272 DOI: 10.1371/journal.pone.0179506] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Lupus is characterized by a loss of B cell tolerance leading to autoantibody production. In this study, we explored the mechanisms underlying this loss of tolerance using B6 congenic mice with an interval from New Zealand Black chromosome 1 (denoted c1(96–100)) sufficient for anti-nuclear antibody production. Transgenes for soluble hen egg white lysozyme (sHEL) and anti-HEL immunoglobulin were crossed onto this background and various tolerance mechanisms examined. We found that c1(96–100) mice produced increased levels of IgM and IgG anti-HEL antibodies compared to B6 mice and had higher proportions of germinal center B cells and long-lived plasma cells, suggesting a germinal center-dependent breach of B cell anergy. Consistent with impaired anergy induction, c1(96–100) double transgenic B cells showed enhanced survival and CD86 upregulation. Hematopoietic chimeric sHEL mice with a mixture of B6 and c1(96–100) HEL transgenic B cells recapitulated these results, suggesting the presence of a B cell autonomous defect. Surprisingly, however, there was equivalent recruitment of B6 and c1(96–100) B cells into germinal centers and differentiation to splenic plasmablasts in these mice. In contrast, there were increased proportions of c1(96–100) T follicular helper cells and long-lived plasma cells as compared to their B6 counterparts, suggesting that both B and T cell defects are required to breach germinal center tolerance in this model. This possibility was further supported by experiments showing an enhanced breach of anergy in double transgenic mice with a longer chromosome 1 interval with additional T cell defects.
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Affiliation(s)
- Nan-Hua Chang
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
| | - Kieran P. Manion
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Christina Loh
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Evelyn Pau
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Yuriy Baglaenko
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | - Joan E. Wither
- Arthritis Centre of Excellence, Division of Genetics and Development, Krembil Research Institute, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
- Division of Rheumatology, University Health Network, Toronto, Ontario, Canada
- * E-mail:
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Zharkova O, Celhar T, Cravens PD, Satterthwaite AB, Fairhurst AM, Davis LS. Pathways leading to an immunological disease: systemic lupus erythematosus. Rheumatology (Oxford) 2017; 56:i55-i66. [PMID: 28375453 PMCID: PMC5410978 DOI: 10.1093/rheumatology/kew427] [Citation(s) in RCA: 100] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2016] [Indexed: 12/25/2022] Open
Abstract
SLE is a chronic autoimmune disease caused by perturbations of the immune system. The clinical presentation is heterogeneous, largely because of the multiple genetic and environmental factors that contribute to disease initiation and progression. Over the last 60 years, there have been a number of significant leaps in our understanding of the immunological mechanisms driving disease processes. We now know that multiple leucocyte subsets, together with inflammatory cytokines, chemokines and regulatory mediators that are normally involved in host protection from invading pathogens, contribute to the inflammatory events leading to tissue destruction and organ failure. In this broad overview, we discuss the main pathways involved in SLE and highlight new findings. We describe the immunological changes that characterize this form of autoimmunity. The major leucocytes that are essential for disease progression are discussed, together with key mediators that propagate the immune response and drive the inflammatory response in SLE.
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Affiliation(s)
- Olga Zharkova
- Singapore Immunology Network, 8A Biomedical Grove, Immunos.,School of Biological Sciences, Nanyang Technological University, Singapore
| | - Teja Celhar
- Singapore Immunology Network, 8A Biomedical Grove, Immunos
| | | | - Anne B Satterthwaite
- Department of Immunology.,The Rheumatic Diseases Division, Department of Internal Medicine, UT Southwestern Medical Center at Dallas, TX, USA
| | - Anna-Marie Fairhurst
- Singapore Immunology Network, 8A Biomedical Grove, Immunos.,School of Biological Sciences, Nanyang Technological University, Singapore.,Department of Immunology
| | - Laurie S Davis
- The Rheumatic Diseases Division, Department of Internal Medicine, UT Southwestern Medical Center at Dallas, TX, USA
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47
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Hemon P, Renaudineau Y, Debant M, Le Goux N, Mukherjee S, Brooks W, Mignen O. Calcium Signaling: From Normal B Cell Development to Tolerance Breakdown and Autoimmunity. Clin Rev Allergy Immunol 2017; 53:141-165. [DOI: 10.1007/s12016-017-8607-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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48
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Getahun A, Wemlinger SM, Rudra P, Santiago ML, van Dyk LF, Cambier JC. Impaired B cell function during viral infections due to PTEN-mediated inhibition of the PI3K pathway. J Exp Med 2017; 214:931-941. [PMID: 28341640 PMCID: PMC5379973 DOI: 10.1084/jem.20160972] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Revised: 10/23/2016] [Accepted: 01/30/2017] [Indexed: 01/27/2023] Open
Abstract
Getahun et al. show that the inositol phosphatase PTEN plays a role in the inhibition of B cell functions observed during acute viral infections. Transient suppression of B cell function often accompanies acute viral infection. However, the molecular signaling circuitry that enforces this hyporesponsiveness is undefined. In this study, experiments identify up-regulation of the inositol phosphatase PTEN (phosphatase and tensin homolog) as primarily responsible for defects in B lymphocyte migration and antibody responses that accompany acute viral infection. B cells from mice acutely infected with gammaherpesvirus 68 are defective in BCR- and CXCR4-mediated activation of the PI3K pathway, and this, we show, is associated with increased PTEN expression. This viral infection-induced PTEN overexpression appears responsible for the suppression of antibody responses observed in infected mice because PTEN deficiency or expression of a constitutively active PI3K rescued function of B cells in infected mice. Conversely, induced overexpression of PTEN in B cells in uninfected mice led to suppression of antibody responses. Finally, we demonstrate that PTEN up-regulation is a common mechanism by which infection induces suppression of antibody responses. Collectively, these findings identify a novel role for PTEN during infection and identify regulation of the PI3K pathway, a mechanism previously shown to silence autoreactive B cells, as a key physiological target to control antibody responses.
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Affiliation(s)
- Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Biomedical Research, National Jewish Health, Denver, CO 80206
| | - Scott M Wemlinger
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Biomedical Research, National Jewish Health, Denver, CO 80206
| | - Pratyaydipta Rudra
- Department of Biostatistics and Informatics, University of Colorado School of Public Health, Aurora, CO 80045
| | - Mario L Santiago
- Division of Infectious Disease, University of Colorado School of Medicine, Aurora, CO 80045
| | - Linda F van Dyk
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045.,Department of Biomedical Research, National Jewish Health, Denver, CO 80206
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, CO 80045 .,Department of Biomedical Research, National Jewish Health, Denver, CO 80206
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49
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He Y, Huang Y, Tu L, Luo J, Yu B, Qian H, Duan L, Shi G. Decreased Gαq expression in T cells correlates with enhanced cytokine production and disease activity in systemic lupus erythematosus. Oncotarget 2016; 7:85741-85749. [PMID: 27965465 PMCID: PMC5349870 DOI: 10.18632/oncotarget.13903] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 12/01/2016] [Indexed: 11/25/2022] Open
Abstract
Aberrant T cell immune responses appear central to the development of systemic lupus erythematosus (SLE). We previously reported that Gαq, the alpha subunit of Gq, regulates T and B cell immune responses, promoting autoimmunity. To address whether Gαq contributes to the pathogenesis of SLE, Gαq mRNA expression was studied using real time-PCR in PBMCs and T cells from SLE patients as well as age- and sex-matched healthy controls. Our results showed that Gαq mRNA expression was decreased in PBMCs and T cells from SLE patients compared to healthy individuals. Correlation analyses showed that Gαq expression in T cells from SLE patients was associated with disease severity (as per SLE Disease Activity Index), the presence of lupus nephritis, and expression of Th1, Th2 and Th17 cytokines. In keeping with clinical results, T-helper cell subsets (Th1, Th2 and Th17) were over-represented in Gαq knockout mice. In addition, Gαq expression in SLE T cells was negatively correlated with the expression of Bcl-2, an anti-apoptotic gene, and positively correlated with the expression of Bax, a pro-apoptotic gene. These data suggest that reduced Gαq levels in T cells may promote enhanced and prolonged T cell activation, contributing to the clinical manifestations of SLE.
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Affiliation(s)
- Yan He
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Yan Huang
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China.,Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China
| | - Lei Tu
- Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei, China
| | - Jiao Luo
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Bing Yu
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Hongyan Qian
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Lihua Duan
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China
| | - Guixiu Shi
- Department of Rheumatology and Clinical Immunology, The First Affiliated Hospital of Xiamen University, Xiamen, Fujian, China.,Fujian University of Traditional Chinese Medicine, Fuzhou, Fujian, China
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Franks SE, Getahun A, Hogarth PM, Cambier JC. Targeting B cells in treatment of autoimmunity. Curr Opin Immunol 2016; 43:39-45. [PMID: 27718447 DOI: 10.1016/j.coi.2016.09.003] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 08/10/2016] [Accepted: 09/13/2016] [Indexed: 01/06/2023]
Abstract
B cells have emerged as effective targets for therapeutic intervention in autoimmunities in which the ultimate effectors are antibodies, as well as those in which T cells are primary drivers of inflammation. Proof of this principle has come primarily from studies of the efficacy of Rituximab, an anti-CD20 mAb that depletes B cells, in various autoimmune settings. These successes have inspired efforts to develop more effective anti-CD20s tailored for specific needs, as well as biologicals and small molecules that suppress B cell function without the risks inherent in B cell depletion. Here we review the current status of B cell-targeted therapies for autoimmunity.
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Affiliation(s)
- S Elizabeth Franks
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Denver, CO, USA
| | - Andrew Getahun
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Denver, CO, USA; Department of Biomedical Research, National Jewish Health, Denver, CO, USA
| | - P Mark Hogarth
- Centre for Biomedicine, Burnet Institute, Melbourne, Vic., Australia; Department of Immunology, Monash University, Melbourne, Vic., Australia; Department of Pathology, University of Melbourne, Melbourne, Vic., Australia
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Denver, CO, USA; Department of Biomedical Research, National Jewish Health, Denver, CO, USA.
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