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Wemlinger SM, Cambier JC. Therapeutic tactics for targeting B lymphocytes in autoimmunity and cancer. Eur J Immunol 2024; 54:e2249947. [PMID: 37816494 DOI: 10.1002/eji.202249947] [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] [Received: 01/13/2023] [Revised: 10/05/2023] [Accepted: 10/09/2023] [Indexed: 10/12/2023]
Abstract
B lymphocytes have become a very popular therapeutic target in a number of autoimmune indications due to their newly appreciated roles, and approachability, in these diseases. Many of the therapies now applied in autoimmunity were initially developed to deplete malignant B cells. These strategies have also been found to benefit patients suffering from such autoimmune diseases as multiple sclerosis, type I diabetes, systemic lupus erythematosus, and rheumatoid arthritis, to name a few. These observations have supported the expansion of research addressing the mechanistic contributions of B cells in these diseases, as well as blossoming of therapeutics that target them. This review seeks to summarize cutting-edge modalities for targeting B cells, including monoclonal antibodies, bispecific antibodies, antibody-drug conjugates, chimeric antigen receptor-T cells, and small molecule inhibitors. Efforts to refine B-cell targeted therapy to eliminate only pathogenic autoreactive cells will be addressed as well as the potential for future B-cell-based cellular therapeutics. Finally, we also address approaches that seek to silence B-cell function without depletion.
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Affiliation(s)
- Scott M Wemlinger
- Department of Immunology and Microbiology, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | - John C Cambier
- Department of Immunology and Microbiology, University of Colorado School of Medicine, Aurora, Colorado, USA
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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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Zhang X, Dai Q, Shan J, Zhang S, Zhang B, Liu S, Zhang Y, Wang Y, Li X, Jin X, Liang D, Ding J, Wang Y, Wen Y. Inhibition of phosphoinositide‑3 kinases γ/δ ameliorates pulmonary granuloma by rescuing Treg function in a sarcoidosis model. Exp Ther Med 2023; 25:225. [PMID: 37123205 PMCID: PMC10133787 DOI: 10.3892/etm.2023.11923] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2022] [Accepted: 02/17/2023] [Indexed: 05/02/2023] Open
Abstract
Sarcoidosis is a multisystem inflammatory disease characterized by the development of Th1/Th17/regulatory T cells (Tregs)-related non-caseating granulomas. Phosphoinositide-3 kinases δ/γ (PI3Kδ/γ) play an important role in the maintenance of effective immunity, especially for Tregs homeostasis and stability. In the present study, superoxide dismutase A (SodA) stimulation was used to establish the sarcoidosis mouse model. The second immune stimulus was accompanied by CAL-101 (PI3Kδ inhibitor) or AS-605240 (PI3Kδ/γ inhibitor) treatment. To detect the effect of the PI3Kδ/γ inhibitor on the morphology of pulmonary granuloma and the activation of the PI3K signaling pathway, hematoxylin and eosin staining and immunofluorescence and western blotting was used, respectively. Fluorescence-activated cell sorting analysis and reverse transcription-quantitative PCR were adopted to detect the effect of the PI3Kδ/γ inhibitor on the SodA-induced sarcoidosis mouse model in respect to immune cell disorder and the function of Treg cells, with CD4+CD25- T cells and CD4+CD25+ T cells sorted by magnetic cell sorting. The results demonstrated that the inhibition of PI3Kδ/γ by transtracheal CAL-101/AS-605240 administration facilitated pulmonary granuloma formation. These therapeutic effects were associated with certain mechanisms, including suppressing the aberrantly activated PI3K/Akt signaling in both pulmonary granuloma and Tregs, particularly rescuing the suppressive function of Tregs. Notably, CAL-101 was more effective in immune modulation compared with AS-605240 and could overcome the aberrantly activated Akt in the lung and Tregs. These results suggest that PI3K/Akt signaling, especially the PI3Kδ subunit, can play a key role in optimal Tregs-mediated protection against pulmonary sarcoidosis. Therefore, transtracheal usage of PI3Kδ/γ inhibitors is an attractive therapy that may be developed into a new immune-therapeutic principle for sarcoidosis in the future.
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Affiliation(s)
- Xian Zhang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Qianqian Dai
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Jiajia Shan
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Shiyun Zhang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Bin Zhang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Siyang Liu
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Yixue Zhang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Ying Wang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Xiaojie Li
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Xuguang Jin
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Dongmei Liang
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
| | - Jingjing Ding
- Department of Respiratory Medicine and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu 210003, P.R. China
| | - Yong Wang
- State Key Laboratory of Analytical Chemistry for Life Science and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
- Correspondence to: Dr Yanting Wen, State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, 22 Hankou Road, Nanjing, Jiangsu 210093, P.R. China.
| | - Yanting Wen
- State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, Nanjing, Jiangsu 210093, P.R. China
- Correspondence to: Dr Yanting Wen, State Key Laboratory of Pharmaceutical Biotechnology and Jiangsu Key Laboratory of Molecular Medicine, The Affiliated Nanjing Drum Tower Hospital, Medical School of Nanjing University, 22 Hankou Road, Nanjing, Jiangsu 210093, P.R. China.
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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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Vanhaesebroeck B, Perry MWD, Brown JR, André F, Okkenhaug K. PI3K inhibitors are finally coming of age. Nat Rev Drug Discov 2021; 20:741-769. [PMID: 34127844 PMCID: PMC9297732 DOI: 10.1038/s41573-021-00209-1] [Citation(s) in RCA: 200] [Impact Index Per Article: 66.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2021] [Indexed: 01/08/2023]
Abstract
Overactive phosphoinositide 3-kinase (PI3K) in cancer and immune dysregulation has spurred extensive efforts to develop therapeutic PI3K inhibitors. Although progress has been hampered by issues such as poor drug tolerance and drug resistance, several PI3K inhibitors have now received regulatory approval - the PI3Kα isoform-selective inhibitor alpelisib for the treatment of breast cancer and inhibitors mainly aimed at the leukocyte-enriched PI3Kδ in B cell malignancies. In addition to targeting cancer cell-intrinsic PI3K activity, emerging evidence highlights the potential of PI3K inhibitors in cancer immunotherapy. This Review summarizes key discoveries that aid the clinical translation of PI3Kα and PI3Kδ inhibitors, highlighting lessons learnt and future opportunities.
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Affiliation(s)
| | - Matthew W D Perry
- Medicinal Chemistry, Research and Early Development, Respiratory & Immunology BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Jennifer R Brown
- CLL Center, Dana-Farber Cancer Institute, Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Fabrice André
- Institut Gustave Roussy, INSERM U981, Université Paris Saclay, Paris, France
| | - Klaus Okkenhaug
- Department of Pathology, University of Cambridge, Cambridge, UK
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Abstract
Based on the PubMed data, we have been performing a yearly evaluation of the publications related to autoimmune diseases and immunology to ascertain the relative weight of the former in the scientific literature. It is particularly intriguing to observe that despite the numerous new avenues of immune-related mechanisms, such as cancer immunotherapy, the proportion of immunology manuscripts related to autoimmunity continues to increase and has been approaching 20% in 2019. As in the previous 13 years, we performed an arbitrary selection of the peer-reviewed articles published by the major dedicated Journals and discussed the common themes which continue to outnumber peculiarites in autoimmune diseases. The investigated areas included systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), psoriatic arthritis (PsA), autoantibodies (autoAbs), and common therapeutic avenues and novel pathogenic mechanisms for autoimmune conditions. Some examples include new pathogenetic evidence which is well represented by IL21 or P2X7 receptor (P2X7R) in SLE or the application of single-cell RNA sequencing (scRNA-seq), mass cytometry, bulk RNA sequencing (RNA-seq), and flow cytometry for the analysis of different cellular populations in RA. Cumulatively and of interest to the clinicians, a large number of findings continue to underline the importance of a strict relationship between basic and clinical science to define new pathogenetic and therapeutic developments. The therapeutic pipeline in autoimmunity continues to grow and maintain a constant flow of new molecules, as well illustrated in RA and PsA, and this is most certainly derived from the new basic evidence and the high-throughput tools applied to autoimmune diseases.
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Cai B, Cai J, Yin Z, Jiang X, Yao C, Ma J, Xue Z, Miao P, Xiao Q, Cheng Y, Qin J, Guo Q, Shen N, Ye Z, Qu B, Ding H. Long non-coding RNA expression profiles in neutrophils revealed potential biomarker for prediction of renal involvement in SLE patients. Rheumatology (Oxford) 2021; 60:1734-1746. [PMID: 33068407 DOI: 10.1093/rheumatology/keaa575] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2020] [Revised: 08/06/2020] [Indexed: 12/13/2022] Open
Abstract
OBJECTIVE The long non-coding RNA plays an important role in inflammation and autoimmune diseases. The aim of this study is to screen and identify abnormally expressed lncRNAs in peripheral blood neutrophils of SLE patients as novel biomarkers and to explore the relationship between lncRNAs levels and clinical features, disease activity and organ damage. METHODS RNA-seq technology was used to screen differentially expressed lncRNAs in neutrophils from SLE patients and healthy donors. Based on the results of screening, candidate lncRNA levels in neutrophils of 88 SLE patients, 35 other connective disease controls, and 78 healthy controls were qualified by real-time quantitative polymerase chain reaction. RESULTS LncRNA expression profiling revealed 360 up-regulated lncRNAs and 224 down-regulated lncRNAs in neutrophils of SLE patients when compared with healthy controls. qPCR assay validated that the expression of Lnc-FOSB-1:1 was significantly decreased in neutrophils of SLE patients when compared with other CTD patients or healthy controls. It correlated negatively with SLE Disease Activity Index 2000 (SLEDAI-2K) score (r = -0.541, P < 0.001) and IFN scores (r = -0.337, P = 0.001). More importantly, decreased Lnc-FOSB-1:1 expression was associated with lupus nephritis. Lower baseline Lnc-FOSB-1:1 level was associated with higher risk of future renal involvement (within an average of 2.6 years) in patients without renal disease at baseline (P = 0.019). CONCLUSION LncRNA expression profile in neutrophils of SLE patients revealed differentially expressed lncRNAs. Validation study on Lnc-FOSB-1:1 suggest that it is a potential biomarker for prediction of near future renal involvement.
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Affiliation(s)
- Bin Cai
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jingyi Cai
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhihua Yin
- Department of Rheumatology, Shenzhen Futian Hospital for Rheumatic Diseases, Shenzhen, China
| | - Xiaoyue Jiang
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Chao Yao
- Laboratory of Molecular Rheumatology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - Jianyang Ma
- China-Australia Centre for Personalized Immunology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Zhixin Xue
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Ping Miao
- Department of Laboratory Medicine, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qingqing Xiao
- Department of Cardiology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Yijun Cheng
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Jialin Qin
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Qiang Guo
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Nan Shen
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Department of Rheumatology, Shenzhen Futian Hospital for Rheumatic Diseases, Shenzhen, China.,Laboratory of Molecular Rheumatology, Institute of Health Sciences, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.,China-Australia Centre for Personalized Immunology, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China.,Center for Autoimmune Genomics and Etiology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA.,Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Zhizhong Ye
- Department of Rheumatology, Shenzhen Futian Hospital for Rheumatic Diseases, Shenzhen, China
| | - Bo Qu
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
| | - Huihua Ding
- Department of Rheumatology, Renji Hospital, Shanghai Institute of Rheumatology, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
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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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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: 12] [Impact Index Per Article: 4.0] [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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Abstract
PURPOSE OF REVIEW Although type 1 diabetes (T1D) is characterized by destruction of the pancreatic beta cells by self-reactive T cells, it has become increasingly evident that B cells also play a major role in disease development, likely functioning as antigen-presenting cells. Here we review the biology of islet antigen-reactive B cells and their participation in autoimmune diabetes. RECENT FINDINGS Relative to late onset, individuals who develop T1D at an early age display increased accumulation of insulin-reactive B cells in islets. This B-cell signature is also associated with rapid progression of disease and responsiveness to B-cell depletion therapy. Also suggestive of B-cell participation in disease is loss of anergy in high-affinity insulin-reactive B cells. Importantly, loss of anergy is seen in patient's healthy first-degree relatives carrying certain T1D risk alleles, suggesting a role early in disease development. SUMMARY Recent studies indicate that islet-reactive B cells may play a pathogenic role very early in T1D development in young patients, and suggest utility of therapies that target these cells.
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Affiliation(s)
- Mia J. Smith
- Barbara Davis Center for 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
| | - Peter A. Gottlieb
- Barbara Davis Center for Diabetes, University of Colorado School of Medicine, Aurora, CO
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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: 31] [Impact Index Per Article: 6.2] [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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