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Qureshi OS, Sutton EJ, Bithell RF, West SM, Cutler RM, McCluskey G, Craggs G, Maroof A, Barnes NM, Humphreys DP, Rapecki S, Smith BJ, Shock A. Interactions of the anti-FcRn monoclonal antibody, rozanolixizumab, with Fcγ receptors and functional impact on immune cells in vitro. MAbs 2024; 16:2300155. [PMID: 38241085 PMCID: PMC10802195 DOI: 10.1080/19420862.2023.2300155] [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: 09/06/2023] [Accepted: 12/22/2023] [Indexed: 01/21/2024] Open
Abstract
Rozanolixizumab is a humanized anti-neonatal Fc receptor (FcRn) monoclonal antibody (mAb) of the immunoglobulin G4 (IgG4) sub-class, currently in clinical development for the treatment of IgG autoantibody-driven diseases. This format is frequently used for therapeutic mAbs due to its intrinsic lower affinity for Fc gamma receptors (FcγR) and lack of C1q engagement. However, with growing evidence suggesting that no Fc-containing agent is truly "silent" in this respect, we explored the engagement of FcγRs and potential functional consequences with rozanolixizumab. In the study presented here, rozanolixizumab was shown to bind to FcγRs in both protein-protein and cell-based assays, and the kinetic data were broadly as expected based on published data for an IgG4 mAb. Rozanolixizumab was also able to mediate antibody bipolar bridging (ABB), a phenomenon that led to a reduction of labeled FcγRI from the surface of human macrophages in an FcRn-dependent manner. However, the presence of exogenous human IgG, even at low concentrations, was able to prevent both binding and ABB events. Furthermore, data from in vitro experiments using relevant human cell types that express both FcRn and FcγRI indicated no evidence for functional sequelae in relation to cellular activation events (e.g., intracellular signaling, cytokine production) upon either FcRn or FcγR binding of rozanolixizumab. These data raise important questions about whether therapeutic antagonistic mAbs like rozanolixizumab would necessarily engage FcγRs at doses typically administered to patients in the clinic, and hence challenge the relevance and interpretation of in vitro assays performed in the absence of competing IgG.
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2
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Thaller AL, Jönsson F, Fiquet O, Marie S, Doisne JM, Girelli-Zubani G, Eri T, Fernandes P, Tatirovsky E, Langa-Vives F, Bruhns P, Strick-Marchand H, Di Santo JP. A human immune system (HIS) mouse model that dissociates roles for mouse and human FcR + cells during antibody-mediated immune responses. Eur J Immunol 2023; 53:e2350454. [PMID: 37621208 DOI: 10.1002/eji.202350454] [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: 02/26/2023] [Revised: 07/21/2023] [Accepted: 08/21/2023] [Indexed: 08/26/2023]
Abstract
Human immune system (HIS) mice provide a model to study human immune responses in vivo. Currently available HIS mouse models may harbor mouse Fc Receptor (FcR)-expressing cells that exert potent effector functions following administration of human Ig. Previous studies showed that the ablation of the murine FcR gamma chain (FcR-γ) results in loss of antibody-dependent cellular cytotoxicity and antibody-dependent cellular phagocytosis in vivo. We created a new FcR-γ-deficient HIS mouse model to compare host (mouse) versus graft (human) effects underlying antibody-mediated immune responses in vivo. FcR-γ-deficient HIS recipients lack expression and function of mouse activating FcRs and can be stably and robustly reconstituted with human immune cells. By screening blood B-cell depletion by rituximab Ig variants, we found that human FcγRs-mediated IgG1 effects, whereas mouse activating FcγRs were dominant in IgG4 effects. Complement played a role as an IgG1 variant (IgG1 K322A) lacking complement binding activity was largely ineffective. Finally, we provide evidence that FcγRIIIA on human NK cells could mediate complement-independent B-cell depletion by IgG1 K322A. We anticipate that our FcR-γ-deficient HIS model will help clarify mechanisms of action of exogenous administered human antibodies in vivo.
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Affiliation(s)
- Anna Louisa Thaller
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Friederike Jönsson
- Institut Pasteur, Antibodies in Therapy and Pathology Unit, Université Paris Cité, Inserm U1222, Paris, France
| | - Oriane Fiquet
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Solenne Marie
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Jean-Marc Doisne
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Giulia Girelli-Zubani
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Toshiki Eri
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Priyanka Fernandes
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Evgeny Tatirovsky
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - Francina Langa-Vives
- Institut Pasteur, Mouse Genetics Engineering Platform, Université Paris Cité, Paris, France
| | - Pierre Bruhns
- Institut Pasteur, Antibodies in Therapy and Pathology Unit, Université Paris Cité, Inserm U1222, Paris, France
| | - Hélène Strick-Marchand
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
| | - James P Di Santo
- Institut Pasteur, Innate Immunity Unit, Université Paris Cité, Inserm U1223, Paris, France
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3
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Rispens T, Huijbers MG. The unique properties of IgG4 and its roles in health and disease. Nat Rev Immunol 2023; 23:763-778. [PMID: 37095254 PMCID: PMC10123589 DOI: 10.1038/s41577-023-00871-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 34.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/20/2023] [Indexed: 04/26/2023]
Abstract
IgG4 is the least abundant subclass of IgG in human serum and has unique functional features. IgG4 is largely unable to activate antibody-dependent immune effector responses and, furthermore, undergoes Fab (fragment antigen binding)-arm exchange, rendering it bispecific for antigen binding and functionally monovalent. These properties of IgG4 have a blocking effect, either on the immune response or on the target protein of IgG4. In this Review, we discuss the unique structural characteristics of IgG4 and how these contribute to its roles in health and disease. We highlight how, depending on the setting, IgG4 responses can be beneficial (for example, in responses to allergens or parasites) or detrimental (for example, in autoimmune diseases, in antitumour responses and in anti-biologic responses). The development of novel models for studying IgG4 (patho)physiology and understanding how IgG4 responses are regulated could offer insights into novel treatment strategies for these IgG4-associated disease settings.
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Affiliation(s)
- Theo Rispens
- Department of Immunopathology, Sanquin Research and Landsteiner Laboratory, Amsterdam, The Netherlands
| | - Maartje G Huijbers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands.
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands.
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4
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Muts RM, den Boer MA, Bardoel BW, Aerts PC, de Haas CJC, Heck AJR, Rooijakkers SHM, Heesterbeek DAC. Artificial surface labelling of Escherichia coli with StrepTagII antigen to study how monoclonal antibodies drive complement-mediated killing. Sci Rep 2023; 13:18836. [PMID: 37914798 PMCID: PMC10620216 DOI: 10.1038/s41598-023-46026-x] [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: 06/21/2023] [Accepted: 10/26/2023] [Indexed: 11/03/2023] Open
Abstract
Antibodies play a key role in the immune defence against Gram-negative bacteria. After binding to bacterial surface antigens, IgG and IgM can activate the complement system and trigger formation of lytic membrane attack complex (MAC) pores. Molecular studies to compare functional activity of antibodies on bacteria are hampered by the limited availability of well-defined antibodies against bacterial surface antigens. Therefore, we genetically engineered E. coli by expressing the StrepTagII antigen into outer membrane protein X (OmpX) and validated that these engineered bacteria were recognised by anti-StrepTagII antibodies. We then combined this antigen-antibody system with a purified complement assay to avoid interference of serum components and directly compare MAC-mediated bacterial killing via IgG1 and pentameric IgM. While both IgG1 and IgM could induce MAC-mediated killing, we show that IgM has an increased capacity to induce complement-mediated killing of E. coli compared to IgG1. While Fc mutations that enhance IgG clustering after target binding could not improve MAC formation, mutations that cause formation of pre-assembled IgG hexamers enhanced the complement activating capacity of IgG1. Altogether, we here present a system to study antibody-dependent complement activation on E. coli and show IgM's enhanced capacity over IgG to induce complement-mediated lysis of E. coli.
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Affiliation(s)
- Remy M Muts
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Maurits A den Boer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomic Center, 3584 CH, Utrecht, The Netherlands
| | - Bart W Bardoel
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Piet C Aerts
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Carla J C de Haas
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute of Pharmaceutical Sciences, Utrecht University, 3584 CH, Utrecht, The Netherlands
- Netherlands Proteomic Center, 3584 CH, Utrecht, The Netherlands
| | - Suzan H M Rooijakkers
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands
| | - Dani A C Heesterbeek
- Department of Medical Microbiology, University Medical Center Utrecht, 3584 CX, Utrecht, The Netherlands.
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5
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de Marco A. Mechanisms underlying the efficacy and safety of IgG, antibody fragments, and design immune biologics. J Allergy Clin Immunol 2023:S0091-6749(23)00082-9. [PMID: 36669622 DOI: 10.1016/j.jaci.2023.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/10/2023] [Accepted: 01/12/2023] [Indexed: 01/19/2023]
Affiliation(s)
- Ario de Marco
- Laboratory for Environmental and Life Sciences, University of Nova Gorica, Nova Gorica, Slovenia.
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6
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Oskam N, Damelang T, Streutker M, Ooijevaar-de Heer P, Nouta J, Koeleman C, Van Coillie J, Wuhrer M, Vidarsson G, Rispens T. Factors affecting IgG4-mediated complement activation. Front Immunol 2023; 14:1087532. [PMID: 36776883 PMCID: PMC9910309 DOI: 10.3389/fimmu.2023.1087532] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2022] [Accepted: 01/16/2023] [Indexed: 01/27/2023] Open
Abstract
Of the four human immunoglobulin G (IgG) subclasses, IgG4 is considered the least inflammatory, in part because it poorly activates the complement system. Regardless, in IgG4 related disease (IgG4-RD) and in autoimmune disorders with high levels of IgG4 autoantibodies, the presence of these antibodies has been linked to consumption and deposition of complement components. This apparent paradox suggests that conditions may exist, potentially reminiscent of in vivo deposits, that allow for complement activation by IgG4. Furthermore, it is currently unclear how variable glycosylation and Fab arm exchange may influence the ability of IgG4 to activate complement. Here, we used well-defined, glyco-engineered monoclonal preparations of IgG4 and determined their ability to activate complement in a controlled system. We show that IgG4 can activate complement only at high antigen and antibody concentrations, via the classical pathway. Moreover, elevated or reduced Fc galactosylation enhanced or diminished complement activation, respectively, with no apparent contribution from the lectin pathway. Fab glycans slightly reduced complement activation. Lastly, we show that bispecific, monovalent IgG4 resulting from Fab arm exchange is a less potent activator of complement than monospecific IgG4. Taken together, these results imply that involvement of IgG4-mediated complement activation in pathology is possible but unlikely.
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Affiliation(s)
- Nienke Oskam
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Amsterdam, Netherlands
| | - Timon Damelang
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Amsterdam, Netherlands.,Department of Immunohematology Experimental, Sanquin Research, Amsterdam, Netherlands.,Department of Biomolecular Mass Spectrometry and Proteomics, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Marij Streutker
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Amsterdam, Netherlands
| | - Pleuni Ooijevaar-de Heer
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Amsterdam, Netherlands
| | - Jan Nouta
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Carolien Koeleman
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Julie Van Coillie
- Department of Immunohematology Experimental, Sanquin Research, Amsterdam, Netherlands.,Department of Biomolecular Mass Spectrometry and Proteomics, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Manfred Wuhrer
- Center for Proteomics and Metabolomics, Leiden University Medical Center, Leiden, Netherlands
| | - Gestur Vidarsson
- Department of Immunohematology Experimental, Sanquin Research, Amsterdam, Netherlands.,Department of Biomolecular Mass Spectrometry and Proteomics, Utrecht Institute for Pharmaceutical Sciences and Bijvoet Center for Biomolecular Research, Utrecht University, Utrecht, Netherlands
| | - Theo Rispens
- Sanquin Research and Landsteiner Laboratory, Department of Immunopathology, Academic Medical Center, Amsterdam, Netherlands
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7
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Qin L, Tang LF, Cheng L, Wang HY. The clinical significance of allergen-specific IgG4 in allergic diseases. Front Immunol 2022; 13:1032909. [PMID: 36389804 PMCID: PMC9648126 DOI: 10.3389/fimmu.2022.1032909] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 09/20/2022] [Indexed: 09/10/2023] Open
Abstract
IgG4 is a subclass of IgG antibody with a unique molecular feature of (Fragment antigen- binding) Fab-arm exchange, allowing bispecific antigen binding in a mono-valent manner. With low binding affinity to C1q and Fcγreceptors, IgG4 is incapable of forming immune complexes and activating the complement pathway, exhibiting a non-inflammatory feature. IgG4 is produced similarly to IgE and is considered a modified reaction to IgE class-switching response under certain conditions. It could also counteract IgE-activated inflammation. However, the clinical significance of IgG4 in allergic diseases is complex and controversial. Three viewpoints have been suggested to describe the role of IgG4. IgG4 can act as a tolerance-inducer to play a protective role under repeated and rapid incremental dosing of allergen exposure in allergen immunotherapy (AIT), supported by allergies in cat raisers and venom desensitization in beekeepers. Another viewpoint accepted by mainstream specialists and guidelines of Food Allergy and Management in different countries points out that food-specific IgG4 is a bystander in food allergy and should not be used as a diagnostic tool in clinical work. However, eosinophilic esophagitis (EoE) investigation revealed a direct clinical relevance between physiopathology and serum IgG4 in cow milk and wheat. These factors indicate that allergen-specific IgG4 plays a multifaceted role in allergic diseases that is protective or pathogenic depending on different allergens or exposure conditions.
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Affiliation(s)
- Lu Qin
- Department of Pulmonology, the Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Lan-Fang Tang
- Department of Pulmonology, the Children’s Hospital of Zhejiang University School of Medicine, Hangzhou, China
| | - Lei Cheng
- Department of Otorhinolaryngology & Clinical Allergy Center, The First Affiliated Hospital, Nanjing Medical University, Nanjing, China
| | - Hui-Ying Wang
- Department of Allergy and Clinical Immunology, the Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
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8
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VanDyke D, Iglesias M, Tomala J, Young A, Smith J, Perry JA, Gebara E, Cross AR, Cheung LS, Dykema AG, Orcutt-Jahns BT, Henclová T, Golias J, Balolong J, Tomasovic LM, Funda D, Meyer AS, Pardoll DM, Hester J, Issa F, Hunter CA, Anderson MS, Bluestone JA, Raimondi G, Spangler JB. Engineered human cytokine/antibody fusion proteins expand regulatory T cells and confer autoimmune disease protection. Cell Rep 2022; 41:111478. [PMID: 36261022 PMCID: PMC9631798 DOI: 10.1016/j.celrep.2022.111478] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 08/02/2022] [Accepted: 09/20/2022] [Indexed: 11/12/2022] Open
Abstract
Low-dose human interleukin-2 (hIL-2) treatment is used clinically to treat autoimmune disorders due to the cytokine's preferential expansion of immunosuppressive regulatory T cells (Tregs). However, off-target immune cell activation and short serum half-life limit the clinical potential of IL-2 treatment. Recent work showed that complexes comprising hIL-2 and the anti-hIL-2 antibody F5111 overcome these limitations by preferentially stimulating Tregs over immune effector cells. Although promising, therapeutic translation of this approach is complicated by the need to optimize dosing ratios and by the instability of the cytokine/antibody complex. We leverage structural insights to engineer a single-chain hIL-2/F5111 antibody fusion protein, termed F5111 immunocytokine (IC), which potently and selectively activates and expands Tregs. F5111 IC confers protection in mouse models of colitis and checkpoint inhibitor-induced diabetes mellitus. These results provide a roadmap for IC design and establish a Treg-biased immunotherapy that could be clinically translated for autoimmune disease treatment.
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Affiliation(s)
- Derek VanDyke
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - Marcos Iglesias
- Vascularized Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jakub Tomala
- Institute of Biotechnology of the Academy of Sciences of the Czech Republic, Vestec 252 50, Czech Republic
| | - Arabella Young
- Diabetes Center, University of California San Francisco, San Francisco, CA 94143, USA; Sean N. Parker Autoimmune Research Laboratory, University of California San Francisco, San Francisco, CA 94143, USA; Huntsman Cancer Institute, University of Utah Health Sciences Center, Salt Lake City, UT 84112, USA; Department of Pathology, University of Utah School of Medicine, Salt Lake City, UT 84112, USA
| | - Jennifer Smith
- Diabetes Center, University of California San Francisco, San Francisco, CA 94143, USA
| | - Joseph A Perry
- Department of Pathobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Edward Gebara
- Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD 21205, USA
| | - Amy R Cross
- Translational Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford OX3 9DU, UK
| | - Laurene S Cheung
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University, Baltimore, MD 21231, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD 21231, USA
| | - Arbor G Dykema
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University, Baltimore, MD 21231, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD 21231, USA
| | - Brian T Orcutt-Jahns
- Department of Bioengineering, Jonsson Comprehensive Cancer Center, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Tereza Henclová
- Institute of Biotechnology of the Academy of Sciences of the Czech Republic, Vestec 252 50, Czech Republic
| | - Jaroslav Golias
- Institute of Microbiology of the Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic
| | - Jared Balolong
- Diabetes Center, University of California San Francisco, San Francisco, CA 94143, USA
| | - Luke M Tomasovic
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA
| | - David Funda
- Institute of Microbiology of the Academy of Sciences of the Czech Republic, Prague 142 20, Czech Republic
| | - Aaron S Meyer
- Department of Bioengineering, Jonsson Comprehensive Cancer Center, Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, University of California, Los Angeles, Los Angeles, CA 90095, USA
| | - Drew M Pardoll
- Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University, Baltimore, MD 21231, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD 21231, USA
| | - Joanna Hester
- Translational Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford OX3 9DU, UK
| | - Fadi Issa
- Translational Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford OX3 9DU, UK
| | - Christopher A Hunter
- Department of Pathobiology, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Mark S Anderson
- Diabetes Center, University of California San Francisco, San Francisco, CA 94143, USA
| | - Jeffrey A Bluestone
- Diabetes Center, University of California San Francisco, San Francisco, CA 94143, USA; Sean N. Parker Autoimmune Research Laboratory, University of California San Francisco, San Francisco, CA 94143, USA; Sonoma Biotherapeutics, South San Francisco, CA 94080, USA
| | - Giorgio Raimondi
- Vascularized Composite Allotransplantation Laboratory, Department of Plastic and Reconstructive Surgery, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA
| | - Jamie B Spangler
- Department of Chemical and Biomolecular Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; Translational Tissue Engineering Center, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Bloomberg-Kimmel Institute for Cancer Immunotherapy, Johns Hopkins University, Baltimore, MD 21231, USA; Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, MD 21231, USA; Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA; Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA; Department of Ophthalmology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
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9
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Kwon OC, Park MC, Kim YG. Correlation between serologic parameters and disease activity of IgG4-related disease: Differences between patients with normal and elevated serum IgG4 concentrations. Front Immunol 2022; 13:1020459. [PMID: 36311699 PMCID: PMC9608652 DOI: 10.3389/fimmu.2022.1020459] [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: 08/16/2022] [Accepted: 09/28/2022] [Indexed: 11/24/2022] Open
Abstract
Objective We aimed to identify serologic parameters that correlate with the disease activity of IgG4-related disease (IgG4-RD) in patients with normal and elevated serum IgG4 concentrations, respectively. Methods This retrospective cohort study included 148 patients with IgG4-RD. Patients were categorized into normal (≤201 mg/dL) and elevated (>201 mg/dL) serum IgG4 concentration groups. Disease activity was assessed using the IgG4-RD responder index (RI). The correlations between IgG4-RD RI and serologic parameters (erythrocyte sedimentation rate [ESR], C-reactive protein, C3, C4, IgG4 concentration, IgG concentration, and IgG4/IgG ratio) were evaluated in each group, using Spearman’s correlation coefficient. Results Of the 148 patients with IgG4-RD, 38 (25.7%) and 110 (74.3%) patients were categorized into the normal and elevated serum IgG4 concentration groups, respectively. In the normal serum IgG4 concentration group, IgG concentration was the only serologic parameter that showed a significant correlation with IgG4-RD RI (rho=0.411, p=0.013). However, in the elevated serum IgG4 concentration group, ESR (rho=0.196, p=0.041), C3 (rho=-0.432, p<0.001), C4 (rho=-0.363, p=0.001), IgG4 concentration (rho=0.423, p<0.001), IgG concentration (rho=0.224, p=0.020), and IgG4/IgG ratio (rho=0.328, p=0.001) correlated with IgG4-RD RI. The combination of C3 and IgG4 concentration (rho=0.509, p<0.001) had the strongest correlation with IgG4-RD RI in this group. Conclusion Among the serologic parameters tested, IgG concentration was the only parameter that correlated with IgG4-RD RI in patients with normal serum IgG4 concentrations, whereas multiple parameters correlated with IgG4-RD RI in those with elevated serum IgG4 concentrations. The combination of C3 and IgG4 concentration had the strongest correlation coefficient in the latter group.
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Affiliation(s)
- Oh Chan Kwon
- Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea
| | - Min-Chan Park
- Division of Rheumatology, Department of Internal Medicine, Yonsei University College of Medicine, Seoul, South Korea
- *Correspondence: Min-Chan Park, ; Yong-Gil Kim,
| | - Yong-Gil Kim
- Division of Rheumatology, Department of Internal Medicine, University of Ulsan, College of Medicine, Asan Medical Center, Seoul, South Korea
- Convergence Medicine Research Center, Asan Institution for Life Science, Asan Medical Center, Seoul, South Korea
- *Correspondence: Min-Chan Park, ; Yong-Gil Kim,
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10
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Delpire B, Van Loon E, Naesens M. The Role of Fc Gamma Receptors in Antibody-Mediated Rejection of Kidney Transplants. Transpl Int 2022; 35:10465. [PMID: 35935272 PMCID: PMC9346079 DOI: 10.3389/ti.2022.10465] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 06/08/2022] [Indexed: 11/25/2022]
Abstract
For the past decades, complement activation and complement-mediated destruction of allograft cells were considered to play a central role in anti-HLA antibody-mediated rejection (AMR) of kidney transplants. However, also complement-independent mechanisms are relevant in the downstream immune activation induced by donor-specific antibodies, such as Fc-gamma receptor (FcγR)-mediated direct cellular activation. This article reviews the literature regarding FcγR involvement in AMR, and the potential contribution of FcγR gene polymorphisms to the risk for antibody mediated rejection of kidney transplants. There is large heterogeneity between the studies, both in the definition of the clinical phenotypes and in the technical aspects. The study populations were generally quite small, except for two larger study cohorts, which obviates drawing firm conclusions regarding the associations between AMR and specific FcγR polymorphisms. Although FcγR are central in the pathophysiology of AMR, it remains difficult to identify genetic risk factors for AMR in the recipient’s genome, independent of clinical risk factors, independent of the donor-recipient genetic mismatch, and in the presence of powerful immunosuppressive agents. There is a need for larger, multi-center studies with standardised methods and endpoints to identify potentially relevant FcγR gene polymorphisms that represent an increased risk for AMR after kidney transplantation.
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Affiliation(s)
- Boris Delpire
- University Hospitals Leuven, Leuven, Belgium
- Nephrology and Renal Transplantation Research Group, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
| | - Elisabet Van Loon
- University Hospitals Leuven, Leuven, Belgium
- Nephrology and Renal Transplantation Research Group, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Department of Nephrology and Kidney Transplantation, University Hospitals Leuven, Leuven, Belgium
| | - Maarten Naesens
- University Hospitals Leuven, Leuven, Belgium
- Nephrology and Renal Transplantation Research Group, Department of Microbiology, Immunology and Transplantation, KU Leuven, Leuven, Belgium
- Department of Nephrology and Kidney Transplantation, University Hospitals Leuven, Leuven, Belgium
- *Correspondence: Maarten Naesens,
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Ogura Y, Yabushita S, Aihara H, Tsukada H, Hashiba T, Furuse S, Fujii A, Ueda Y, Mise N. A case of proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) that responded favorably to steroid therapy. CEN Case Rep 2022; 11:208-215. [PMID: 34628583 PMCID: PMC9061924 DOI: 10.1007/s13730-021-00653-3] [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: 03/10/2021] [Accepted: 09/28/2021] [Indexed: 10/20/2022] Open
Abstract
Proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID) generally has a poor prognosis and the consensus is that it needs to be treated with clone-directed therapy. However, the prognosis of PGNMID is heterogenous and some cases have been successfully treated using other therapeutic strategies. We herein report a case of PGNMID that responded favorably to steroids without clone-directed therapy. An 18-year-old woman was referred to a nephrologist with proteinuria detected in an annual health check-up. Over a 3-year period, the concentration of creatinine (Cr) increased from 0.76 to 1.00 mg/dL and proteinuria from 0.35 to 1.9 g/g Cr. Monoclonal gammopathies were not detected in her serum or urine. Based on the findings of kidney biopsy at the age of 21 years, the patient was diagnosed with proliferative glomerulonephritis with monoclonal IgG1-kappa deposits. The histological feature was mesangial proliferative glomerulonephritis with advanced glomerulosclerosis, which is a rare presentation of PGNMID. Intravenous methylprednisolone pulse therapy was initiated, followed by oral prednisolone at a dose of 30 mg daily. One year later, a second kidney biopsy revealed a significant decrease in mesangial deposits of IgG1-kappa. Prednisolone was gradually tapered and discontinued 2 years after the first kidney biopsy. At the time of prednisolone withdrawal, urinalysis showed proteinuria of 0.2 g/g Cr without hematuria. Kidney function remained stable throughout the treatment period.
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Affiliation(s)
- Yoshiyasu Ogura
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Sayaka Yabushita
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Hideki Aihara
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Hiroyuki Tsukada
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Toyohiro Hashiba
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Satoshi Furuse
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan
| | - Akiko Fujii
- Department of Pathology, Saitama Medical Center, Dokkyo Medical University, 2-1-50 Minamikoshigaya, Koshigaya city, Saitama, 343-8555, Japan
| | - Yoshihiko Ueda
- Department of Pathology, Saitama Medical Center, Dokkyo Medical University, 2-1-50 Minamikoshigaya, Koshigaya city, Saitama, 343-8555, Japan
| | - Naobumi Mise
- Department of Nephrology, Division of Internal Medicine, Mitsui Memorial Hospital, 1 Kanda-izumi-cho, Chiyoda-ku, Tokyo, 101-8643, Japan.
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12
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Golinski ML, Lemieux A, Maho-Vaillant M, Barray M, Drouot L, Schapman D, Petit M, Hertl M, Boyer O, Calbo S, Joly P, Hébert V. The Diversity of Serum Anti-DSG3 IgG Subclasses Has a Major Impact on Pemphigus Activity and Is Predictive of Relapses After Treatment With Rituximab. Front Immunol 2022; 13:849790. [PMID: 35371083 PMCID: PMC8965561 DOI: 10.3389/fimmu.2022.849790] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 02/14/2022] [Indexed: 11/13/2022] Open
Abstract
Introduction We studied the distribution and in vitro pathogenicity of anti-DSG3 IgG subclasses during the course of pemphigus vulgaris (PV). Methods We longitudinally studied the distribution of anti-DSG3 IgG subclasses (before versus after treatment) in sera from PV patients, using an addressable-laser bead immunoassay (ALBIA). The in vitro pathogenicity of corresponding sera was tested using keratinocyte dissociation and immunofluorescence assays. Results Sixty-five sera were assessed at baseline (33 from patients treated with rituximab and 32 with corticosteroids). Sixty-three percent of these baseline sera contained 2 or more anti-DSG3 IgG subclasses versus 35.7% of sera from patients in complete remission (CR) and 75.0% of sera from patients with persistent disease activity after treatment. IgG4 was the most frequently detected anti-DSG3 IgG subclass, both in patients with disease activity and in those in CR. The presence of three or more anti-DSG3 IgG subclasses was predictive of relapse, in particular when it included IgG3, with a positive predictive value of 62.5% and a negative predictive value of 92%. While anti-DSG3 IgG4 Abs from sera collected before treatment were most often pathogenic, anti-DSG3 IgG4 from sera collected after treatment were pathogenic only after adjusting their titer to the one measured before treatment. The IgG3 fraction containing anti-DSG3 Abs also had an in vitro pathogenic effect. The disappearance of the pathogenic effect of some sera after removal of anti-DSG3 IgG3 suggested an additional effect of this IgG subclass. Conclusion The serum levels and number of anti-DSG3 IgG subclasses drive the pathogenic effect of pemphigus sera and may predict the occurrence of relapses.
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Affiliation(s)
- Marie-Laure Golinski
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Dermatology, Rouen, France
| | - Alexandre Lemieux
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Dermatology, Rouen, France
| | - Maud Maho-Vaillant
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Dermatology, Rouen, France
| | - Marion Barray
- Normandie Univ, UNIROUEN, Inserm U1234, Rouen, France
| | | | | | - Marie Petit
- Normandie Univ, UNIROUEN, Inserm U1234, Rouen, France
| | - Michael Hertl
- Department of Dermatology and Allergology, Philipps University, Marburg, Germany
| | - Olivier Boyer
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Immunology, Rouen, France
| | | | - Pascal Joly
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Dermatology, Rouen, France
| | - Vivien Hébert
- Normandie Univ, UNIROUEN, Inserm U1234, CHU Rouen, Department of Dermatology, Rouen, France
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Koneczny I, Tzartos J, Mané-Damas M, Yilmaz V, Huijbers MG, Lazaridis K, Höftberger R, Tüzün E, Martinez-Martinez P, Tzartos S, Leypoldt F. IgG4 Autoantibodies in Organ-Specific Autoimmunopathies: Reviewing Class Switching, Antibody-Producing Cells, and Specific Immunotherapies. Front Immunol 2022; 13:834342. [PMID: 35401530 PMCID: PMC8986991 DOI: 10.3389/fimmu.2022.834342] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Accepted: 02/28/2022] [Indexed: 12/24/2022] Open
Abstract
Organ-specific autoimmunity is often characterized by autoantibodies targeting proteins expressed in the affected tissue. A subgroup of autoimmunopathies has recently emerged that is characterized by predominant autoantibodies of the IgG4 subclass (IgG4-autoimmune diseases; IgG4-AID). This group includes pemphigus vulgaris, thrombotic thrombocytopenic purpura, subtypes of autoimmune encephalitis, inflammatory neuropathies, myasthenia gravis and membranous nephropathy. Although the associated autoantibodies target specific antigens in different organs and thus cause diverse syndromes and diseases, they share surprising similarities in genetic predisposition, disease mechanisms, clinical course and response to therapies. IgG4-AID appear to be distinct from another group of rare immune diseases associated with IgG4, which are the IgG4-related diseases (IgG4-RLD), such as IgG4-related which have distinct clinical and serological properties and are not characterized by antigen-specific IgG4. Importantly, IgG4-AID differ significantly from diseases associated with IgG1 autoantibodies targeting the same organ. This may be due to the unique functional characteristics of IgG4 autoantibodies (e.g. anti-inflammatory and functionally monovalent) that affect how the antibodies cause disease, and the differential response to immunotherapies of the IgG4 producing B cells/plasmablasts. These clinical and pathophysiological clues give important insight in the immunopathogenesis of IgG4-AID. Understanding IgG4 immunobiology is a key step towards the development of novel, IgG4 specific treatments. In this review we therefore summarize current knowledge on IgG4 regulation, the relevance of class switching in the context of health and disease, describe the cellular mechanisms involved in IgG4 production and provide an overview of treatment responses in IgG4-AID.
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Affiliation(s)
- Inga Koneczny
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
- *Correspondence: Inga Koneczny,
| | - John Tzartos
- Neuroimmunology, Tzartos NeuroDiagnostics, Athens, Greece
- 2nd Department of Neurology, “Attikon” University Hospital, School of Medicine, National and Kapodistrian University of Athens, Athens, Greece
| | - Marina Mané-Damas
- Research Group Neuroinflammation and Autoimmunity, Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Vuslat Yilmaz
- Department of Neuroscience, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Maartje G. Huijbers
- Department of Human Genetics, Leiden University Medical Center, Leiden, Netherlands
- Department of Neurology, Leiden University Medical Center, Leiden, Netherlands
| | - Konstantinos Lazaridis
- Department of Immunology, Laboratory of Immunology, Hellenic Pasteur Institute, Athens, Greece
| | - Romana Höftberger
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Vienna, Austria
| | - Erdem Tüzün
- Department of Neuroscience, Aziz Sancar Institute of Experimental Medicine, Istanbul University, Istanbul, Turkey
| | - Pilar Martinez-Martinez
- Research Group Neuroinflammation and Autoimmunity, Department of Psychiatry and Neuropsychology, Faculty of Health, Medicine and Life Sciences, Maastricht University, Maastricht, Netherlands
| | - Socrates Tzartos
- Neuroimmunology, Tzartos NeuroDiagnostics, Athens, Greece
- Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece
| | - Frank Leypoldt
- Neuroimmunology, Institute of Clinical Chemistry and Department of Neurology, UKSH Kiel/Lübeck, Kiel University, Kiel, Germany
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Uchida K, Okazaki K. Current status of type 1 (IgG4-related) autoimmune pancreatitis. J Gastroenterol 2022; 57:695-708. [PMID: 35916965 PMCID: PMC9522839 DOI: 10.1007/s00535-022-01891-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/30/2022] [Indexed: 02/04/2023]
Abstract
In 1995, Yoshida et al. proposed first the concept of "autoimmune pancreatitis" (AIP). Since then, AIP has been accepted as a new pancreatic inflammatory disease and is now divided two subtypes. Type 1 AIP affected immunoglobulin G4 (IgG4) and implicates the pancreatic manifestation of IgG4-related disease, while type 2 is characterized by neutrophil infiltration and granulocytic epithelial lesions (GEL). Recent research has clarified the clinical and pathophysiological aspects of type 1 AIP, which is more than type 2 among the Japanese population. However, many details remain unclear about the pathogenesis and progression of this disease. In this review, we discuss the current knowledge and recent advances relating to type 1 AIP.
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Affiliation(s)
- Kazushige Uchida
- grid.278276.e0000 0001 0659 9825Department of Gastroenterology and Hepatology, Kochi Medical School, Kochi University, Okocho-Kohasu, Nankoku, Kochi 783-8505 Japan
| | - Kazuichi Okazaki
- grid.410783.90000 0001 2172 5041Kansai Medical University Kouri Hospital, 8-45 Kourihondori, Neyagawa, Osaka 572-8551 Japan
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15
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Congdon EE, Jiang Y, Sigurdsson EM. Targeting tau only extracellularly is likely to be less efficacious than targeting it both intra- and extracellularly. Semin Cell Dev Biol 2021; 126:125-137. [PMID: 34896021 DOI: 10.1016/j.semcdb.2021.12.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 12/11/2022]
Abstract
Aggregation of the tau protein is thought to be responsible for the neurodegeneration and subsequent functional impairments in diseases that are collectively named tauopathies. Alzheimer's disease is the most common tauopathy, but the group consists of over 20 different diseases, many of which have tau pathology as their primary feature. The development of tau therapies has mainly focused on preventing the formation of and/or clearing these aggregates. Of these, immunotherapies that aim to either elicit endogenous tau antibodies or deliver exogenous ones are the most common approach in clinical trials. While their mechanism of action can involve several pathways, both extra- and intracellular, pharmaceutical companies have primarily focused on antibody-mediated clearance of extracellular tau. As we have pointed out over the years, this is rather surprising because it is well known that most of pathological tau protein is found intracellularly. It has been repeatedly shown by several groups over the past decades that antibodies can enter neurons and that their cellular uptake can be enhanced by various means, particularly by altering their charge. Here, we will briefly describe the potential extra- and intracellular mechanisms involved in antibody-mediated clearance of tau pathology, discuss these in the context of recent failures of some of the tau antibody trials, and finally provide a brief overview of how the intracellular efficacy of tau antibodies can potentially be further improved by certain modifications that aim to enhance tau clearance via specific intracellular degradation pathways.
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Affiliation(s)
- Erin E Congdon
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States.
| | - Yixiang Jiang
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States
| | - Einar M Sigurdsson
- Department of Neuroscience and Physiology, Neuroscience Institute, New York University Grossman School of Medicine, New York, NY 10016, United States; Department of Psychiatry, New York University Grossman School of Medicine, New York, NY 10016, United States.
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16
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Freiwald T, Afzali B. Renal diseases and the role of complement: Linking complement to immune effector pathways and therapeutics. Adv Immunol 2021; 152:1-81. [PMID: 34844708 PMCID: PMC8905641 DOI: 10.1016/bs.ai.2021.09.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The complement system is an ancient and phylogenetically conserved key danger sensing system that is critical for host defense against pathogens. Activation of the complement system is a vital component of innate immunity required for the detection and removal of pathogens. It is also a central orchestrator of adaptive immune responses and a constituent of normal tissue homeostasis. Once complement activation occurs, this system deposits indiscriminately on any cell surface in the vicinity and has the potential to cause unwanted and excessive tissue injury. Deposition of complement components is recognized as a hallmark of a variety of kidney diseases, where it is indeed associated with damage to the self. The provenance and the pathophysiological role(s) played by complement in each kidney disease is not fully understood. However, in recent years there has been a renaissance in the study of complement, with greater appreciation of its intracellular roles as a cell-intrinsic system and its interplay with immune effector pathways. This has been paired with a profusion of novel therapeutic agents antagonizing complement components, including approved inhibitors against complement components (C)1, C3, C5 and C5aR1. A number of clinical trials have investigated the use of these more targeted approaches for the management of kidney diseases. In this review we present and summarize the evidence for the roles of complement in kidney diseases and discuss the available clinical evidence for complement inhibition.
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Affiliation(s)
- Tilo Freiwald
- Immunoregulation Section, Kidney Diseases Branch, National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), Bethesda, MD, United States; Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany
| | - Behdad Afzali
- Department of Nephrology, University Hospital Frankfurt, Goethe-University, Frankfurt am Main, Germany.
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17
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Yu Z, Zhang M, Jing H, Chen P, Cao R, Pan J, Luo B, Yu Y, Quarles BM, Xiong W, Rivner MH, Mei L. Characterization of LRP4/Agrin Antibodies From a Patient With Myasthenia Gravis. Neurology 2021; 97:e975-e987. [PMID: 34233932 PMCID: PMC8448554 DOI: 10.1212/wnl.0000000000012463] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Accepted: 06/22/2021] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND AND OBJECTIVE To determine whether human anti-LRP4/agrin antibodies are pathogenic in mice and to investigate underpinning pathogenic mechanisms. METHODS Immunoglobulin (Ig) was purified from a patient with myasthenia gravis (MG) with anti-LRP4/agrin antibodies and transferred to mice. Mice were characterized for body weight, muscle strength, twitch and tetanic force, neuromuscular junction (NMJ) functions including compound muscle action potential (CMAP) and endplate potentials, and NMJ structure. Effects of the antibodies on agrin-elicited muscle-specific tyrosine kinase (MuSK) activation and AChR clustering were studied and the epitopes of these antibodies were identified. RESULTS Patient Ig-injected mice had MG symptoms, including weight loss and muscle weakness. Decreased CMAPs, reduced twitch and tetanus force, compromised neuromuscular transmission, and NMJ fragmentation and distortion were detected in patient Ig-injected mice. Patient Ig inhibited agrin-elicited MuSK activation and AChR clustering. The patient Ig recognized the β3 domain of LRP4 and the C-terminus of agrin and reduced agrin-enhanced LRP4-MuSK interaction. DISCUSSION Anti-LRP4/agrin antibodies in the patient with MG is pathogenic. It impairs the NMJ by interrupting agrin-dependent LRP4-MuSK interaction.
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Affiliation(s)
- Zheng Yu
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Meiying Zhang
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Hongyang Jing
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Peng Chen
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Rangjuan Cao
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Jinxiu Pan
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Bin Luo
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Yue Yu
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Brandy M Quarles
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Wencheng Xiong
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH
| | - Michael H Rivner
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH.
| | - Lin Mei
- From the Department of Neurosciences (Z.Y., M.Z., H.J., P.C., R.C., J.P., B.L., W.X., L.M.), School of Medicine, Case Western Reserve University, Cleveland; Beachwood High School (Y.Y.), OH; Department of Neurology (B.M.Q., M.H.R.), Augusta University, GA; and Louis Stokes Cleveland Veterans Affairs Medical Center (W.X., L.M.), OH.
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Grüner J, Stengel H, Werner C, Appeltshauser L, Sommer C, Villmann C, Doppler K. Anti-contactin-1 Antibodies Affect Surface Expression and Sodium Currents in Dorsal Root Ganglia. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2021; 8:8/5/e1056. [PMID: 34429341 PMCID: PMC8407150 DOI: 10.1212/nxi.0000000000001056] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 05/17/2021] [Indexed: 01/13/2023]
Abstract
Background and Objectives As autoantibodies to contactin-1 from patients with chronic inflammatory demyelinating polyradiculoneuropathy not only bind to the paranodes where they are supposed to cause conduction failure but also bind to other neuronal cell types, we aimed to investigate the effect of anti–contactin-1 autoantibodies on contactin-1 surface expression in cerebellar granule neurons, dorsal root ganglion neurons, and contactin-1–transfected human embryonic kidney 293 cells. Methods Immunocytochemistry including structured illumination microscopy and immunoblotting was used to determine expression levels of contactin-1 and/or sodium channels after long-term exposure to autoantibodies from 3 seropositive patients. For functional analysis of sodium channels, whole-cell recordings of sodium currents were performed on dorsal root ganglion neurons incubated with anti–contactin-1 autoantibodies. Results We found a reduction in contactin-1 expression levels on dorsal root ganglion neurons, cerebellar granule neurons, and contactin-1–transfected human embryonic kidney 293 cells and decreased dorsal root ganglion sodium currents after long-term exposure to anti–contactin-1 autoantibodies. Sodium channel density did not decrease. Discussion Our results demonstrate a direct effect of anti–contactin-1 autoantibodies on the surface expression of contactin-1 and sodium currents in dorsal root ganglion neurons. This may be the pathophysiologic correlate of sensory ataxia reported in these patients.
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Affiliation(s)
- Julia Grüner
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Helena Stengel
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Christian Werner
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Luise Appeltshauser
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Claudia Sommer
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Carmen Villmann
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany
| | - Kathrin Doppler
- From the Department of Neurology (J.G., H.S., L.A., C.S., K.D.), University Hospital Würzburg, Germany; Department of Biotechnology and Biophysics (C.W.), Julius-Maximilians-University of Würzburg; and Institute of Clinical Neurobiology (C.V.), University Hospital, Julius-Maximilians-University of Würzburg, Germany.
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The Role of Fc Receptors on the Effectiveness of Therapeutic Monoclonal Antibodies. Int J Mol Sci 2021; 22:ijms22168947. [PMID: 34445651 PMCID: PMC8396266 DOI: 10.3390/ijms22168947] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2021] [Revised: 08/14/2021] [Accepted: 08/16/2021] [Indexed: 12/12/2022] Open
Abstract
Since the approval of the first monoclonal antibody (mAb) in 1986, a huge effort has been made to guarantee safety and efficacy of therapeutic mAbs. As of July 2021, 118 mAbs are approved for the European market for a broad range of clinical indications. In order to ensure clinical efficacy and safety aspects, (pre-)clinical experimental approaches evaluate the respective modes of action (MoA). In addition to antigen-specificity including binding affinity and -avidity, MoA comprise Fc-mediated effector functions such as antibody dependent cellular cytotoxicity (ADCC) and the closely related antibody dependent cellular phagocytosis (ADCP). For this reason, a variety of cell-based assays have been established investigating effector functions of therapeutic mAbs with different effector/target-cell combinations and several readouts including Fcγ receptor (FcγR)-mediated lysis, fluorescence, or luminescence. Optimized FcγR-mediated effector functions regarding clinical safety and efficacy are addressed with modification strategies such as point mutations, altered glycosylation patterns, combination of different Fc subclasses (cross isotypes), and Fc-truncation of the mAb. These strategies opened the field for a next generation of therapeutic mAbs. In conclusion, it is of major importance to consider FcγR-mediated effector functions for the efficacy of therapeutic mAbs.
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20
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Chong HY, Leow CY, Leow CH. Generation of soluble, disulfide-rich JEV NS1 protein recognizable by anti-NS1 antibodies through a simplified, in vitro refolding approach. Int J Biol Macromol 2021; 185:485-493. [PMID: 34174313 DOI: 10.1016/j.ijbiomac.2021.06.146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 06/20/2021] [Accepted: 06/21/2021] [Indexed: 12/01/2022]
Abstract
Co-existence of Japanese Encephalitis virus (JEV) with highly homologous antigenic epitopes results in antibody-based serodiagnosis being inaccurate at detecting and distinguishing JEV from other flaviviruses. This often causes misdiagnosis and inefficient treatments of flavivirus infection. Generation of JEV NS1 protein remains a challenge as it is notably expressed in the form of inactive aggregates known as inclusion bodies using bacterial expression systems. This study evaluated two trxB and gor E. coli strains in producing soluble JEV NS1 via a cold-shock expression system. High yield of JEV NS1 inclusion bodies was produced using cold-shocked expression system. Subsequently, a simplified yet successful approach in generating soluble, active JEV NS1 protein through solubilization, purification and in vitro refolding of JEV NS1 protein from inclusion bodies was developed. A step-wise dialysis refolding approach was used to facilitate JEV NS1 refolding. The authenticity of the refolded JEV NS1 was confirmed by specific antibody binding on indirect ELISA commercial anti-NS1 antibodies which showed that the refolded JEV NS1 was highly immunoreactive. This presented approach is cost-effective, and negates the need for mammalian or insect cell expression systems in order to synthesize this JEV NS1 protein of important diagnostic and therapeutic relevance in Japanese Encephalitis disease.
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Affiliation(s)
- Hui Ying Chong
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Glugor, Penang, Malaysia
| | - Chiuan Yee Leow
- School of Pharmaceutical Science, Universiti Sains Malaysia, Glugor, Penang, Malaysia
| | - Chiuan Herng Leow
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Glugor, Penang, Malaysia.
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21
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Abstract
Antibody-dependent complement activation plays a major role in various pathophysiological processes in our body, including infection, inflammation, autoimmunity, and transplant rejection. In order to activate complement, antibodies should bind to target cells and recruit complement component C1. C1 is a large, multimolecular complex that consists of the antibody recognition protein C1q and a heterotetramer of proteases (C1r2s2). Although it is believed that interactions between C1 and IgGs are solely mediated by C1q, we here show that C1r2s2 proteases affect the capacity of C1q to form an avid complex with surface-bound IgG molecules. Furthermore, we demonstrate that C1q–IgG stability is influenced by IgG oligomerization and that promoting IgG oligomerization improves phagocytosis of the pathogenic bacterium Staphylococcus aureus. Complement is an important effector mechanism for antibody-mediated clearance of infections and tumor cells. Upon binding to target cells, the antibody’s constant (Fc) domain recruits complement component C1 to initiate a proteolytic cascade that generates lytic pores and stimulates phagocytosis. The C1 complex (C1qr2s2) consists of the large recognition protein C1q and a heterotetramer of proteases C1r and C1s (C1r2s2). While interactions between C1 and IgG-Fc are believed to be mediated by the globular heads of C1q, we here find that C1r2s2 proteases affect the capacity of C1q to form an avid complex with surface-bound IgG molecules (on various 2,4-dinitrophenol [DNP]-coated surfaces and pathogenic Staphylococcus aureus). The extent to which C1r2s2 contributes to C1q–IgG stability strongly differs between human IgG subclasses. Using antibody engineering of monoclonal IgG, we reveal that hexamer-enhancing mutations improve C1q–IgG stability, both in the absence and presence of C1r2s2. In addition, hexamer-enhanced IgGs targeting S. aureus mediate improved complement-dependent phagocytosis by human neutrophils. Altogether, these molecular insights into complement binding to surface-bound IgGs could be important for optimal design of antibody therapies.
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22
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Peng S, Lu W, Jiang X, Xu X, Wu Y. IgG deposits in the mesangium and capillary loops predict poor renal outcome in patients with IgA nephropathy: a single-center retrospective study. Ren Fail 2021; 42:902-911. [PMID: 32869693 PMCID: PMC7946043 DOI: 10.1080/0886022x.2020.1811120] [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] [Indexed: 12/16/2022] Open
Abstract
Background Glomerular IgG deposition in patients with IgA nephropathy (IgAN) has been shown to be associated with poor renal survival; however, most published studies to date are too small-scale and inconsistent to provide guidance for clinical practice. Methods Based on renal biopsy findings, 742 patients were divided into the following groups: (i) IgA deposition alone (IgA) vs IgA + IgG deposition (IgA + IgG) and (ii) IgG co-deposition confined to the mesangium vs mesangium + capillary loops (CLs). The clinicopathological variables at biopsy and renal outcome were assessed. Results Of the 742 patients, 182 had IgG co-deposition and 51 had IgG deposits in the mesangium + CLs. Patients with IgG co-deposition were associated with severe clinical and pathological lesions, especially those with a location of IgG deposits in the mesangium +CLs. Kaplan–Meier analysis revealed that a lower renal cumulative survival rate was present in both patients with IgG co-deposition and those with a location of IgG deposits in the mesangium + CLs (all p < 0.05). Moreover, patients with a higher intensity of glomerular IgG deposits or C3 deposits or C1q deposits were also associated with a lower survival rate. A multivariate Cox regression model identified the location of IgG deposits in the mesangium + CLs as an independent risk factor for poor prognosis (HR, 2.11; 95% CI: 1.06–4.18; p = 0.005). Conclusions Glomerular IgG co-deposition and the location of glomerular IgG deposits in the mesangium + CLs were both associated with adverse renal outcomes, but only the location of glomerular IgG deposits in the CLs was an independent risk factor for poor prognosis in IgAN.
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Affiliation(s)
- Siqi Peng
- Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Wen Lu
- Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xiao Jiang
- Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Xingxin Xu
- Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yonggui Wu
- Department of Nephrology, the First Affiliated Hospital of Anhui Medical University, Hefei, China
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23
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Bestard O, Couzi L, Crespo M, Kessaris N, Thaunat O. Stratifying the humoral risk of candidates to a solid organ transplantation: a proposal of the ENGAGE working group. Transpl Int 2021; 34:1005-1018. [PMID: 33786891 DOI: 10.1111/tri.13874] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 03/26/2021] [Indexed: 12/30/2022]
Abstract
Detection of circulating antibodies directed against human leukocyte antigen (HLA) molecules, which corresponds to the current definition of 'sensitized patient', has been shown to have a severe impact on both access to transplantation and, if the anti-HLA antibodies are specific to the selected donor, survival of the graft. However, not all donor-specific antibodies (DSA) are equally harmful to the graft and progress in the understanding of humoral memory has led to the conclusion that absence of DSA at transplantation does not rule out the possibility that the patient has a preformed cellular humoral memory against the graft (thereby defining a category of DSA-negative sensitized recipients). Technological progress has led to the generation of new assays that offer unprecedented precision in exploring the different layers (serological and cellular) of alloimmune humoral memory. Based on this recent knowledge, the EuropeaN Guidelines for the mAnagement of Graft rEcipients (ENGAGE) working group to propose an updated definition of sensitization in candidates for solid organ transplantation - one that moves away from the current binary division towards a definition based on homogenous strata with similar humoral risk.
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Affiliation(s)
- Oriol Bestard
- Kidney Transplant Unit, Nephrology Department, Bellvitge University Hospital, Barcelona, Spain.,Bellvitge Research Institute (IDIBELL), Barcelona, Spain
| | - Lionel Couzi
- Nephrology-Transplantation-Dialysis, CHU Bordeaux, Bordeaux, France.,CNRS-UMR 5164 Immuno ConcEpT, Bordeaux University, Bordeaux, France
| | - Marta Crespo
- Department of Nephrology, Hospital del Mar, Barcelona, Spain.,Nephropathies Research Group, Hospital del Mar Medical Research Institute (IMIM), Barcelona, Spain
| | - Nicos Kessaris
- Department of Nephrology and Transplantation, Guy's Hospital, London, UK.,King's College London, London, UK
| | - Olivier Thaunat
- Service de Transplantation, Néphrologie et Immunologie Clinique, Hôpital Edouard Herriot, Lyon, France.,Université Claude-Bernard Lyon I, Lyon, France.,Institut National de la Santé et de la Recherche Médicale U1111, Lyon, France
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24
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Breville G, Zamberg I, Sadallah S, Stephan C, Ponte B, Seebach JD. Case Report: Severe Complement-Mediated Thrombotic Microangiopathy in IgG4-Related Disease Secondary to Anti-Factor H IgG4 Autoantibodies. Front Immunol 2021; 11:604759. [PMID: 33643292 PMCID: PMC7905310 DOI: 10.3389/fimmu.2020.604759] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Accepted: 12/14/2020] [Indexed: 01/13/2023] Open
Abstract
Objective To first describe and estimate the potential pathogenic role of Ig4 autoantibodies in complement-mediated thrombotic microangiopathy (TMA) in a patient with IgG4-related disease (IgG4-RD). Methods This study is a case report presenting a retrospective review of the patient’s medical chart. Plasma complement C3 and C4 levels, immunoglobulin isotypes and subclasses were determined by nephelometry, the complement pathways’ activity (CH50, AP50, MBL) using WIESLAB® Complement System assays. Human complement factor H levels, anti-complement factor H auto-antibodies were analyzed by ELISA, using HRP-labeled secondary antibodies specific for human IgG, IgG4, and IgA, respectively. Genetic analyses were performed by exome sequencing of 14 gens implicated in complement disorders, as well as multiplex ligation-dependent probe amplification looking specifically for CFH, CFHR1-2-3, and 5. Results Our brief report presents the first case of IgG4-RD with complement-mediated TMA originating from both pathogenic CFHR 1 and CFHR 4 genes deletions, and inhibitory anti-complement factor H autoantibodies of the IgG4 subclass. Remission was achieved with plasmaphereses, corticosteroids, and cyclophosphamide. Following remission, the patient was diagnosed with lymphocytic meningitis and SARS-CoV-2 pneumonia with an uneventful recovery. Conclusion IgG4-RD can be associated with pathogenic IgG4 autoantibodies. Genetic predisposition such as CFHR1 and CFHR4 gene deletions enhance the susceptibility to the formation of inhibitory anti-Factor H IgG4 antibodies.
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Affiliation(s)
- Gautier Breville
- Department of Medicine, Division of Immunology and Allergy, Geneva University Hospitals, Geneva, Switzerland.,Department of Clinical Neurosciences, Division of Neurology, Geneva University Hospitals, Geneva, Switzerland
| | - Ido Zamberg
- Department of Medicine, Division of General Internal Medicine, Geneva University Hospitals, Geneva, Switzerland.,Department of Anaesthesiology, Division of Anaesthesiology, Clinical Pharmacology, Intensive Care and Emergency Medicine, Geneva University Hospitals, Geneva, Switzerland
| | - Salima Sadallah
- Département de médecine de laboratoire et pathologie, Service d'immunologie et d'allergie, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
| | - Caroline Stephan
- Department of Medicine, Immuno-Hematology Unit, Geneva University Hospitals, Geneva, Switzerland
| | - Belen Ponte
- Department of Medicine, Division of Nephrology, Geneva University Hospitals, Geneva, Switzerland
| | - Jörg D Seebach
- Department of Medicine, Division of Immunology and Allergy, Geneva University Hospitals, Geneva, Switzerland
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25
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Abstract
The opposing roles of innate and adaptive immune cells in suppressing or supporting cancer initiation, progression, metastasis and response to therapy has been long debated. The mechanisms by which different monocyte and T cell subtypes affect and modulate cancer have been extensively studied. However, the role of B cells and their subtypes have remained elusive, perhaps partially due to their heterogeneity and range of actions. B cells can produce a variety of cytokines and present tumor-derived antigens to T cells in combination with co-stimulatory or inhibitory ligands based on their phenotype. Unlike most T cells, B cells can be activated by innate immune stimuli, such as endotoxin. Furthermore, the isotype and specificity of the antibodies produced by plasma cells regulate distinct immune responses, including opsonization, antibody-mediated cellular cytotoxicity (ADCC) and complement activation. B cells are shaped by the tumor environment (TME), with the capability to regulate the TME in return. In this review, we will describe the mechanisms of B cell action, including cytokine production, antigen presentation, ADCC, opsonization, complement activation and how they affect tumor development and response to immunotherapy. We will also discuss how B cell fate within the TME is affected by tumor stroma, microbiome and metabolism.
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Affiliation(s)
- Shabnam Shalapour
- Department of Cancer Biology, University of Texas MD Anderson Cancer Center, Houston, TX 77054, USA.
| | - Michael Karin
- Department of Pharmacology, School of Medicine, University of California San Diego, CA 92093, USA; Laboratory of Gene Regulation and Signal Transduction, Department of Pharmacology, School of Medicine, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA
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26
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Byrne AB, Talarico LB. Role of the complement system in antibody-dependent enhancement of flavivirus infections. Int J Infect Dis 2020; 103:404-411. [PMID: 33352325 DOI: 10.1016/j.ijid.2020.12.039] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 12/10/2020] [Accepted: 12/13/2020] [Indexed: 11/26/2022] Open
Abstract
Flavivirus infections have increased dramatically in the last decades in tropical and subtropical regions of the world. Antibody-dependent enhancement of dengue virus infections has been one of the main hypotheses to explain severity of disease and one of the major challenges to safe and effective vaccine development. In the presence of cross-reactive sub-neutralizing concentrations of anti-dengue antibodies, immune complexes can amplify viral infection in mononuclear phagocytic cells, triggering a cytokine cascade and activating the complement system that leads to severe disease. The complement system comprises a family of plasma and cellular surface proteins that recognize pathogen associated molecular patterns, modified ligands and immune complexes, interacting in a regulated manner and forming an enzymatic cascade. Pathogenic as well as protective effects of complement have been reported in flavivirus infections. This review provides updated knowledge on complement activation during flavivirus infection, including antiviral effects of complement and its regulation, as well as mechanisms of complement evasion and dysregulation of complement activity during viral infection leading to pathogenesis. Particularly, insights into classical pathway activation and its protective role on antibody-dependent enhancement of flavivirus infections are highlighted.
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Affiliation(s)
- Alana B Byrne
- Laboratorio de Investigaciones Infectológicas y Biología Molecular, Unidad de Infectología, Departamento de Medicina, Hospital de Niños Dr. Ricardo Gutiérrez, Buenos Aires 1425, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina.
| | - Laura B Talarico
- Laboratorio de Investigaciones Infectológicas y Biología Molecular, Unidad de Infectología, Departamento de Medicina, Hospital de Niños Dr. Ricardo Gutiérrez, Buenos Aires 1425, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires 1425, Argentina.
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27
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Gorovits B. Current Considerations for Immunoglobulin Isotype Characterization of Antibody Response against Biotherapeutics. AAPS JOURNAL 2020; 22:144. [PMID: 33161459 DOI: 10.1208/s12248-020-00530-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Accepted: 10/30/2020] [Indexed: 12/15/2022]
Abstract
The ability of biotherapeutics to induce immune response in patients has been broadly accepted. Humoral immune response to biotherapeutics is expected to be polyclonal in nature with a high degree of diversity, including treatment-induced anti-drug antibodies (ADA) immunoglobulin isotype composition. Therapeutics with strong potential to induce immunity may produce a T cell-dependent response resulting in a gradual transition from initial IgM based to mature, IgG-based ADAs. Immunoglobulin class switch and transition to high affinity IgG1 and IgG4 antibodies were linked to a reduced drug efficacy, accelerated clearance, development of drug neutralizing antibodies, and modulation of hypersensitivity reaction rates. Examples presented herein demonstrate that understanding of isotype composition of ADA response can be highly important to predict future of disease progression. Isotype characterization of ADA response can be viewed highly useful, particularly for high immunogenicity risk biotherapeutics although may be less relevant or used as a research tool only for medium and low immunogenicity risk level therapeutics. Isotype-specific characteristics, methods of detection, and several case studies are presented herein.
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28
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Reinhard L, Stahl RAK, Hoxha E. Is primary membranous nephropathy a complement mediated disease? Mol Immunol 2020; 128:195-204. [PMID: 33142137 DOI: 10.1016/j.molimm.2020.10.017] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2020] [Revised: 09/04/2020] [Accepted: 10/20/2020] [Indexed: 12/25/2022]
Abstract
Membranous nephropathy (MN) is an immune complex mediated disease. Although limited to the kidney, in up to 20% of patients MN is associated with other autoimmune, infectious or malignant diseases. The initial pathogenetic event in what is still considered "primary" MN is the binding of circulating autoantibodies to proteins (autoantigens) expressed in glomerular podocytes. This antibody binding leads to the formation of immune complexes in the glomerular basement membrane. There is clinical and experimental evidence that these immune deposits lead to the activation of the complement system. Experimental studies in the MN model of Heymann's nephritis show that the terminal membrane attack complex (MAC) of the complement system induces a disturbance of the glomerular filtration barrier and leads to proteinuria, the clinical hallmark of MN. After the discovery of the phospholipase A2 receptor 1 and thrombospondin type 1 domain containing protein 7A as endogenous antigens, it is assumed that IgG4 antibodies directed against these proteins induce MN in over 85% of patients with primary MN. As a result, the role of complement in the pathogenesis of MN needs to be defined in light of these developments. In this review we describe the current knowledge on the function of the complement system in primary MN and discuss the open questions, which have to be solved for a better understanding of the potential role of complement in the pathophysiology of primary MN.
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Affiliation(s)
- Linda Reinhard
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany
| | - Rolf A K Stahl
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
| | - Elion Hoxha
- III. Department of Medicine, University Medical Center Hamburg-Eppendorf, Martinistrasse 52, 20246, Hamburg, Germany.
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29
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Koneczny I. Update on IgG4-mediated autoimmune diseases: New insights and new family members. Autoimmun Rev 2020; 19:102646. [PMID: 32801046 DOI: 10.1016/j.autrev.2020.102646] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 03/08/2020] [Indexed: 12/23/2022]
Abstract
Antibodies of IgG4 subclass are exceptional players of the immune system, as they are considered to be immunologically inert and functionally monovalent, and as such may be part of classical tolerance mechanisms. IgG4 antibodies are found in a range of different diseases, including IgG4-related diseases, allergy, cancer, rheumatoid arthritis, helminth infection and IgG4 autoimmune diseases, where they may be pathogenic or protective. IgG4 autoimmune diseases are an emerging new group of diseases that are characterized by pathogenic, antigen-specific autoantibodies of IgG4 subclass, such as MuSK myasthenia gravis, pemphigus vulgaris and thrombotic thrombocytopenic purpura. The list of IgG4 autoantigens is rapidly growing and to date contains 29 candidate antigens. Interestingly, IgG4 autoimmune diseases are restricted to four distinct organs: 1) the central and peripheral nervous system, 2) the kidney, 3) the skin and mucous membranes and 4) the vascular system and soluble antigens in the blood circulation. The pathogenicity of IgG4 can be validated using our classification system, and is usually excerted by functional blocking of protein-protein interaction.
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Affiliation(s)
- Inga Koneczny
- Division of Neuropathology and Neurochemistry, Department of Neurology, Medical University of Vienna, Währingergürtel 18-20, 1090 Vienna, Austria.
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30
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Herman LS, James LK. Moving with the kines: Chemokine receptor expression regulates the migration and differentiation of IgG4‐expressing B cells. Eur J Immunol 2020. [DOI: 10.1002/eji.202048802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lou Salomé Herman
- Blizard InstituteQueen Mary University of London London E1 2AT United Kingdom
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31
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Hsieh SC, Shen CY, Liao HT, Chen MH, Wu CH, Li KJ, Lu CS, Kuo YM, Tsai HC, Tsai CY, Yu CL. The Cellular and Molecular Bases of Allergy, Inflammation and Tissue Fibrosis in Patients with IgG4-related Disease. Int J Mol Sci 2020; 21:ijms21145082. [PMID: 32708432 PMCID: PMC7404109 DOI: 10.3390/ijms21145082] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Revised: 07/09/2020] [Accepted: 07/14/2020] [Indexed: 12/16/2022] Open
Abstract
IgG4-related disease (IgG4-RD) is a spectrum of complex fibroinflammatory disorder with protean manifestations mimicking malignant neoplasms, infectious or non-infectious inflammatory process. The histopathologic features of IgG4-RD include lymphoplasmacytic infiltration, storiform fibrosis and obliterative phlebitis together with increased in situ infiltration of IgG4 bearing-plasma cells which account for more than 40% of all IgG-producing B cells. IgG4-RD can also be diagnosed based on an elevated serum IgG4 level of more than 110 mg/dL (normal < 86.5 mg/mL in adult) in conjunction with protean clinical manifestations in various organs such as pancreato–hepatobiliary inflammation with/without salivary/lacrimal gland enlargement. In the present review, we briefly discuss the role of genetic predisposition, environmental factors and candidate autoantibodies in the pathogenesis of IgG4-RD. Then, we discuss in detail the immunological paradox of IgG4 antibody, the mechanism of modified Th2 response for IgG4 rather than IgE antibody production and the controversial issues in the allergic reactions of IgG4-RD. Finally, we extensively review the implications of different immune-related cells, cytokines/chemokines/growth factors and Toll-like as well as NOD-like receptors in the pathogenesis of tissue fibro-inflammatory reactions. Our proposals for the future investigations and prospective therapeutic strategies for IgG4-RD are shown in the last part.
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Affiliation(s)
- Song-Chou Hsieh
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Chieh-Yu Shen
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Hsien-Tzung Liao
- Division of Allergy, Immunology & Rheumatology, Taipei Veterans General Hospital & National Yang-Ming University, Taipei 11217, Taiwan; (H.-T.L.); (M.-H.C.); (H.-C.T.)
| | - Ming-Han Chen
- Division of Allergy, Immunology & Rheumatology, Taipei Veterans General Hospital & National Yang-Ming University, Taipei 11217, Taiwan; (H.-T.L.); (M.-H.C.); (H.-C.T.)
| | - Cheng-Han Wu
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Ko-Jen Li
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Cheng-Shiun Lu
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Yu-Min Kuo
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
| | - Hung-Cheng Tsai
- Division of Allergy, Immunology & Rheumatology, Taipei Veterans General Hospital & National Yang-Ming University, Taipei 11217, Taiwan; (H.-T.L.); (M.-H.C.); (H.-C.T.)
| | - Chang-Youh Tsai
- Division of Allergy, Immunology & Rheumatology, Taipei Veterans General Hospital & National Yang-Ming University, Taipei 11217, Taiwan; (H.-T.L.); (M.-H.C.); (H.-C.T.)
- Correspondence: (C.-Y.T.); (C.-L.Y.); Tel.: +886-2-28712121 (ext. 3366) (C.-Y.T.); +886-2-23123456 (ext. 65011) (C.-L.Y.)
| | - Chia-Li Yu
- Division of Rheumatology, Immunology & Allergy, National Taiwan University Hospital, National Taiwan University College of Medicine, Taipei 10002, Taiwan; (S.-C.H.); (C.-Y.S.); (C.-H.W.); (K.-J.L.); (C.-S.L.); (Y.-M.K.)
- Correspondence: (C.-Y.T.); (C.-L.Y.); Tel.: +886-2-28712121 (ext. 3366) (C.-Y.T.); +886-2-23123456 (ext. 65011) (C.-L.Y.)
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32
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Borges LS, Richman DP. Muscle-Specific Kinase Myasthenia Gravis. Front Immunol 2020; 11:707. [PMID: 32457737 PMCID: PMC7225350 DOI: 10.3389/fimmu.2020.00707] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 03/30/2020] [Indexed: 01/02/2023] Open
Abstract
Thirty to fifty percent of patients with acetylcholine receptor (AChR) antibody (Ab)-negative myasthenia gravis (MG) have Abs to muscle specific kinase (MuSK) and are referred to as having MuSK-MG. MuSK is a 100 kD single-pass post-synaptic transmembrane receptor tyrosine kinase crucial to the development and maintenance of the neuromuscular junction. The Abs in MuSK-MG are predominantly of the IgG4 immunoglobulin subclass. MuSK-MG differs from AChR-MG, in exhibiting more focal muscle involvement, including neck, shoulder, facial and bulbar-innervated muscles, as well as wasting of the involved muscles. MuSK-MG is highly associated with the HLA DR14-DQ5 haplotype and occurs predominantly in females with onset in the fourth decade of life. Some of the standard treatments of AChR-MG have been found to have limited effectiveness in MuSK-MG, including thymectomy and cholinesterase inhibitors. Therefore, current treatment involves immunosuppression, primarily by corticosteroids. In addition, patients respond especially well to B cell depletion agents, e.g., rituximab, with long-term remissions. Future treatments will likely derive from the ongoing analysis of the pathogenic mechanisms underlying this disease, including histologic and physiologic studies of the neuromuscular junction in patients as well as information derived from the development and study of animal models of the disease.
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Affiliation(s)
- Lucia S Borges
- Department of Neurology, University of California, Davis, Davis, CA, United States
| | - David P Richman
- Department of Neurology, University of California, Davis, Davis, CA, United States
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Marsh‐Wakefield F, Ashhurst T, Trend S, McGuire HM, Juillard P, Zinger A, Jones AP, Kermode AG, Hawke S, Grau GE, Hart PH, Byrne SN. IgG 3 + B cells are associated with the development of multiple sclerosis. Clin Transl Immunology 2020; 9:e01133. [PMID: 32355561 PMCID: PMC7190396 DOI: 10.1002/cti2.1133] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/06/2020] [Accepted: 04/07/2020] [Indexed: 12/29/2022] Open
Abstract
OBJECTIVES Disease-modifying therapies (DMTs) targeting B cells are amongst the most effective for preventing multiple sclerosis (MS) progression. IgG3 antibodies and their uncharacterised B-cell clones are predicted to play a pathogenic role in MS. Identifying subsets of IgG3 + B cells involved in MS progression could improve diagnosis, could inform timely disease intervention and may lead to new DMTs that target B cells more specifically. METHODS We designed a 31-parameter B-cell-focused mass cytometry panel to interrogate the role of peripheral blood IgG3 + B cells in MS progression of two different patient cohorts: one to investigate the B-cell subsets involved in conversion from clinically isolated syndrome (CIS) to MS; and another to compare MS patients with inactive or active stages of disease. Each independent cohort included a group of non-MS controls. RESULTS Nine distinct CD20+IgD-IgG3 + B-cell subsets were identified. Significant changes in the proportion of CD21+CD24+CD27-CD38- and CD27+CD38hiCD71hi memory B-cell subsets correlated with changes in serum IgG3 levels and time to conversion from CIS to MS. The same CD38- double-negative B-cell subset was significantly elevated in MS patients with active forms of the disease. A third CD21+CD24+CD27+CD38- subset was elevated in patients with active MS, whilst narrowband UVB significantly reduced the proportion of this switched-memory B-cell subset. CONCLUSION We have identified previously uncharacterised subsets of IgG3 + B cells and shown them to correlate with autoimmune attacks on the central nervous system (CNS). These results highlight the potential for therapies that specifically target IgG3 + B cells to impact MS progression.
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Affiliation(s)
- Felix Marsh‐Wakefield
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
| | - Thomas Ashhurst
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Viral Immunopathology LaboratoryDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
- Sydney Cytometry FacilityCharles Perkins CentreThe University of Sydney and Centenary InstituteSydneyNSWAustralia
| | - Stephanie Trend
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
- Centre for Neuromuscular and Neurological DisordersPerron Institute for Neurological and Translational ScienceUniversity of Western AustraliaPerthWAAustralia
| | - Helen M McGuire
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Ramaciotti Facility for Human Systems BiologyThe University of SydneySydneyNSWAustralia
- Translational Immunology LaboratoryDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Pierre Juillard
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Anna Zinger
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Anderson P Jones
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
| | - Allan G Kermode
- Centre for Neuromuscular and Neurological DisordersPerron Institute for Neurological and Translational ScienceUniversity of Western AustraliaPerthWAAustralia
- Institute for Immunology and Infectious DiseaseMurdoch UniversityPerthWAAustralia
| | - Simon Hawke
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
- Central West Neurology and NeurosurgeryOrangeNSWAustralia
| | - Georges E Grau
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Vascular Immunology UnitDepartment of PathologyThe University of SydneySydneyNSWAustralia
| | - Prue H Hart
- Telethon Kids InstituteUniversity of Western AustraliaPerthWAAustralia
| | - Scott N Byrne
- School of Medical SciencesFaculty of Medicine and HealthThe University of SydneySydneyNSWAustralia
- Charles Perkins CentreThe University of SydneySydneyNSWAustralia
- Centre for Immunology and Allergy ResearchWestmead Institute for Medical ResearchWestmeadNSWAustralia
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R409K mutation prevents acid-induced aggregation of human IgG4. PLoS One 2020; 15:e0229027. [PMID: 32182240 PMCID: PMC7077836 DOI: 10.1371/journal.pone.0229027] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2019] [Accepted: 01/28/2020] [Indexed: 11/20/2022] Open
Abstract
Human immunoglobulin G isotype 4 (IgG4) antibodies are suitable for use in either the antagonist or agonist format because their low effector functions prevent target cytotoxicity or unwanted cytokine secretion. However, while manufacturing therapeutic antibodies, they are exposed to low pH during purification, and IgG4 is more susceptible to low-pH-induced aggregation than IgG1. Therefore, we investigated the underlying mechanisms of IgG4 aggregation at low pH and engineered an IgG4 with enhanced stability. By swapping the constant regions of IgG1 and IgG4, we determined that the constant heavy chain (CH3) domain is critical for aggregate formation, but a core-hinge-stabilizing S228P mutation in IgG4 is insufficient for preventing aggregation. To identify the aggregation-prone amino acid, we substituted the CH3 domain of IgG4 with that of IgG1, changing IgG4 Arg409 to a Lys, thereby preventing the aggregation of the IgG4 variant as effectively as in IgG1. A stabilizing effect was also recorded with other variable-region variants. Analysis of thermal stability using differential scanning calorimetry revealed that the R409K substitution increased the Tm value of CH3, suggesting that the R409K mutation contributed to the structural strengthening of the CH3-CH3 interaction. The R409K mutation did not influence the binding to antigens/human Fcγ receptors; whereas, the concurrent S228P and R409K mutations in IgG4 suppressed Fab-arm exchange drastically and as effectively as in IgG1, in both in vitro and in vivo in mice models. Our findings suggest that the IgG4 R409K variant represents a potential therapeutic IgG for use in low-effector-activity format that exhibits increased stability.
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Saito S, Namisaki H, Hiraishi K, Takahashi N, Iida S. Engineering a human IgG2 antibody stable at low pH. Protein Sci 2020; 29:1186-1195. [PMID: 32142185 DOI: 10.1002/pro.3852] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2019] [Revised: 03/01/2020] [Accepted: 03/03/2020] [Indexed: 12/16/2022]
Abstract
IgG2 subclass antibodies have unique properties that include low effector function and a rigid hinge region. Although some IgG2 subclasses have been clinically tested and approved for therapeutic use, they have a higher propensity than IgG1 for aggregation, which can curtail or abolish their biological activity and enhance their immunogenicity. In this regard, acid-induced aggregation of monoclonal antibodies during purification and virus inactivation must be prevented. In the present study, we replaced the constant domain of IgG2 with that of IgG1, using anti-2,4-dinitrophenol (DNP) IgG2 as a model antibody, and investigated whether that would confer greater stability. While the anti-DNP IgG2 antibody showed significant aggregation at low pH, this was reduced for the IgG2 antibody containing the IgG1 CH2 domain. Substituting three amino acids within the CH2 domain-namely, F300Y, V309L, and T339A (IgG2_YLA)-reduced aggregation at low pH and increased CH2 transition temperature, as determined by differential scanning calorimetric analysis. IgG2_YLA exhibited similar antigen-binding capacity to IgG2, low affinity for FcγRIIIa, and low binding ability to C1q. The same YLA substitution also reduced the aggregation of panitumumab, another IgG2 antibody, at low pH. Our engineered human IgG2 antibody showed reduced aggregation during bioprocessing and provides a basis for designing improved IgG2 antibodies for therapeutic applications.
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Affiliation(s)
- Seiji Saito
- Antibody & Biologics Research Laboratories, R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Hiroshi Namisaki
- Open Innovation Department, R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Keiko Hiraishi
- Antibody & Biologics Research Laboratories, R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Nobuaki Takahashi
- Research Functions Unit, R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
| | - Shigeru Iida
- Antibody & Biologics Research Laboratories, R&D Division, Kyowa Kirin Co., Ltd., Tokyo, Japan
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Dumet C, Pottier J, Gouilleux-Gruart V, Watier H. Insights into the IgG heavy chain engineering patent landscape as applied to IgG4 antibody development. MAbs 2019; 11:1341-1350. [PMID: 31556789 PMCID: PMC6816381 DOI: 10.1080/19420862.2019.1664365] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Despite being the least abundant immunoglobulin G in human plasma, IgG4 are used therapeutically when weak effector functions are needed. The increase in engineered IgG4-based antibodies on the market led us to study the patent landscape of IgG4 Fc engineering, i.e., patents claiming modifications in the heavy chain. Thirty-seven relevant patent families were identified, comprising hundreds of IgG4 Fc variants focusing on removal of residual effector functions (since IgG4s bind to FcγRI and weakly to other FcγRs), half-life enhancement and IgG4 stability. Given the number of expired or soon to expire major patents in those 3 areas, companies developing blocking antibodies now have, or will in the near future, access to free tools to design silenced, half-life extended and stable IgG4 antibodies.
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Affiliation(s)
- Christophe Dumet
- EA7501, Team "Fc Receptors, Antibodies and Microenvironnement", Université de Tours , France
| | - Jérémy Pottier
- EA7501, Team "Fc Receptors, Antibodies and Microenvironnement", Université de Tours , France
| | - Valérie Gouilleux-Gruart
- EA7501, Team "Fc Receptors, Antibodies and Microenvironnement", Université de Tours , France.,CHRU de Tours , France
| | - Hervé Watier
- EA7501, Team "Fc Receptors, Antibodies and Microenvironnement", Université de Tours , France.,CHRU de Tours , France
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Kramer CSM, Franke-van Dijk MEI, Priddey AJ, Pongrácz T, Gnudi E, Car H, Karahan GE, van Beelen E, Zilvold-van den Oever CCC, Rademaker HJ, de Haan N, Wuhrer M, Kosmoliaptsis V, Parren PWHI, Mulder A, Roelen DL, Claas FHJ, Heidt S. Recombinant human monoclonal HLA antibodies of different IgG subclasses recognising the same epitope: Excellent tools to study differential effects of donor-specific antibodies. HLA 2019; 94:415-424. [PMID: 31403241 PMCID: PMC6851673 DOI: 10.1111/tan.13664] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 07/11/2019] [Accepted: 08/09/2019] [Indexed: 02/07/2023]
Abstract
In the field of transplantation, the humoural immune response against mismatched HLA antigens of the donor is associated with inferior graft survival, but not in every patient. Donor‐specific HLA antibodies (DSA) of different immunoglobulin G (IgG) subclasses may have differential effects on the transplanted organ. Recombinant technology allows for the generation of IgG subclasses of a human monoclonal antibody (mAb), while retaining its epitope specificity. In order to enable studies on the biological function of IgG subclass HLA antibodies, we used recombinant technology to generate recombinant human HLA mAbs from established heterohybridomas. We generated all four IgG subclasses of a human HLA class I and class II mAb and showed that the different subclasses had a comparable affinity, normal human Fc glycosylation, and retained HLA epitope specificity. For both mAbs, the IgG1 and IgG3 isotypes were capable of binding complement component 3d (C3d) and efficient in complement‐dependent cell lysis against their specific targets, while the IgG2 and IgG4 subclasses were not able to induce cytotoxicity. Considering the fact that the antibody‐binding site and properties remained unaffected, these IgG subclass HLA mAbs are excellent tools to study the function of individual IgG subclass HLA class I and class II‐specific antibodies in a controlled fashion.
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Affiliation(s)
- Cynthia S M Kramer
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Marry E I Franke-van Dijk
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Tamás Pongrácz
- Center of Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Elena Gnudi
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Helena Car
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Gonca E Karahan
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Els van Beelen
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | | | | | - Noortje de Haan
- Center of Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | - Manfred Wuhrer
- Center of Proteomics and Metabolomics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Paul W H I Parren
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands.,Lava Therapeutics, 's-Hertogenbosch, The Netherlands
| | - Arend Mulder
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Dave L Roelen
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Frans H J Claas
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
| | - Sebastiaan Heidt
- Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, Leiden, The Netherlands
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Tolbert WD, Subedi GP, Gohain N, Lewis GK, Patel KR, Barb AW, Pazgier M. From Rhesus macaque to human: structural evolutionary pathways for immunoglobulin G subclasses. MAbs 2019; 11:709-724. [PMID: 30939981 PMCID: PMC6601566 DOI: 10.1080/19420862.2019.1589852] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Revised: 02/15/2019] [Accepted: 02/22/2019] [Indexed: 10/27/2022] Open
Abstract
The Old World monkey, Rhesus macaque (Macaca mulatta, Mm), is frequently used as a primate model organism in the study of human disease and to test new vaccines/antibody treatments despite diverging before chimpanzees and orangutans. Mm and humans share 93% genome identity with substantial differences in the genes of the adaptive immune system that lead to different functional IgG subclass characteristics, Fcγ receptors expressed on innate immune cells, and biological interactions. These differences put limitations on Mm use as a primary animal model in the study of human disease and to test new vaccines/antibody treatments. Here, we comprehensively analyzed molecular properties of the Fc domain of the four IgG subclasses of Rhesus macaque to describe potential mechanisms for their interactions with effector cell Fc receptors. Our studies revealed less diversity in the overall structure among the Mm IgG Fc, with MmIgG1 Fc being the most structurally like human IgG3, although its CH2 loops and N297 glycan mobility are comparable to human IgG1. Furthermore, the Fcs of Mm IgG3 and 4 lack the structural properties typical for their human orthologues that determine IgG3's reduced interaction with the neonatal receptor and IgG4's ability for Fab-arm exchange and its weaker Fcγ receptor interactions. Taken together, our data indicate that MmIgG1-4 are less structurally divergent than the human IgGs, with only MmIgG1 matching the molecular properties of human IgG1 and 3, the most active IgGs in terms of Fcγ receptor binding and Fc-mediated functions. PDB accession numbers for deposited structures are 6D4E, 6D4I, 6D4M, and 6D4N for MmIgG1 Fc, MmIgG2 Fc, MmIgG3 Fc, and MmIgG4 Fc, respectively.
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Affiliation(s)
- William David Tolbert
- Division of Vaccine Research, Institute of Human Virology of University of Maryland School of Medicine, Baltimore, MD, USA
- Infectious Disease Division, Uniformed Services University of the Health Sciences, Bethesda, MD
| | - Ganesh Prasad Subedi
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology of Iowa State University, Ames, IA, USA
| | - Neelakshi Gohain
- Division of Vaccine Research, Institute of Human Virology of University of Maryland School of Medicine, Baltimore, MD, USA
| | - George Kenneth Lewis
- Division of Vaccine Research, Institute of Human Virology of University of Maryland School of Medicine, Baltimore, MD, USA
| | - Kashyap Rajesh Patel
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology of Iowa State University, Ames, IA, USA
| | - Adam Wesley Barb
- Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology of Iowa State University, Ames, IA, USA
| | - Marzena Pazgier
- Division of Vaccine Research, Institute of Human Virology of University of Maryland School of Medicine, Baltimore, MD, USA
- Infectious Disease Division, Uniformed Services University of the Health Sciences, Bethesda, MD
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Higgins BW, McHeyzer-Williams LJ, McHeyzer-Williams MG. Programming Isotype-Specific Plasma Cell Function. Trends Immunol 2019; 40:345-357. [PMID: 30846256 DOI: 10.1016/j.it.2019.01.012] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 01/28/2019] [Accepted: 01/29/2019] [Indexed: 01/06/2023]
Abstract
Helper T cell induced plasma cells (PCs) that secrete class-switched neutralizing antibody are paramount to effective immunity. Following class-switch recombination (CSR), antigen-activated B cells differentiate into extrafollicular PCs or mature in germinal centers (GCs) to produce high-affinity memory B cells and follicular PCs. Many studies focus on the core transcriptional programs that drive central PC functions of longevity and antibody secretion. However, it is becoming clear that these central programs are further subdivided across antibody isotype with separable transcriptional trajectories. Divergent functions emerge at CSR, persist through PC terminal differentiation and further assort memory PC function following antigen recall. Here, we emphasize recent work that assorts divergent isotype-specific PC function across four major modules of immune protection.
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Affiliation(s)
- Brett W Higgins
- The Scripps Research Institute, Department of Immunology and Microbiology, La Jolla, CA 92037, USA
| | - Louise J McHeyzer-Williams
- The Scripps Research Institute, Department of Immunology and Microbiology, La Jolla, CA 92037, USA. https://twitter.com/mmw_lmw
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Christensen SM, Belew AT, El-Sayed NM, Tafuri WL, Silveira FT, Mosser DM. Host and parasite responses in human diffuse cutaneous leishmaniasis caused by L. amazonensis. PLoS Negl Trop Dis 2019; 13:e0007152. [PMID: 30845223 PMCID: PMC6405045 DOI: 10.1371/journal.pntd.0007152] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2018] [Accepted: 01/11/2019] [Indexed: 02/01/2023] Open
Abstract
Diffuse cutaneous leishmaniasis (DCL) is a rare form of leishmaniasis where parasites grow uncontrolled in diffuse lesions across the skin. Meta-transcriptomic analysis of biopsies from DCL patients infected with Leishmania amazonensis demonstrated an infiltration of atypical B cells producing a surprising preponderance of the IgG4 isotype. DCL lesions contained minimal CD8+ T cell transcripts and no evidence of persistent TH2 responses. Whereas localized disease exhibited activated (so-called M1) macrophage presence, transcripts in DCL suggested a regulatory macrophage (R-Mϕ) phenotype with higher levels of ABCB5, DCSTAMP, SPP1, SLAMF9, PPARG, MMPs, and TM4SF19. The high levels of parasite transcripts in DCL and the remarkable uniformity among patients afforded a unique opportunity to study parasite gene expression in this disease. Patterns of parasite gene expression in DCL more closely resembled in vitro parasite growth in resting macrophages, in the absence of T cells. In contrast, parasite gene expression in LCL revealed 336 parasite genes that were differently upregulated, relative to DCL and in vitro macrophage growth, and these transcripts may represent transcripts that are produced by the parasite in response to host immune pressure.
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Affiliation(s)
- Stephen M. Christensen
- Department of Cell Biology and Molecular Genetics and the Maryland Pathogen Research Institute, University of Maryland, College Park, MD United States of America
| | - Ashton T. Belew
- Department of Cell Biology and Molecular Genetics and the Maryland Pathogen Research Institute, University of Maryland, College Park, MD United States of America
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD United States of America
| | - Najib M. El-Sayed
- Department of Cell Biology and Molecular Genetics and the Maryland Pathogen Research Institute, University of Maryland, College Park, MD United States of America
- Center for Bioinformatics and Computational Biology, University of Maryland, College Park, MD United States of America
| | - Wagner L. Tafuri
- Departamento de Patologia Geral, Universidade Federal de Minas Geras, Belo Horizonte, Brazil
| | - Fernando T. Silveira
- Evandro Chagas Institute, Tropical Medicine Nucleus, Federal University of Pará, Belém, PA Brazil
| | - David M. Mosser
- Department of Cell Biology and Molecular Genetics and the Maryland Pathogen Research Institute, University of Maryland, College Park, MD United States of America
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Zheng M, Ujiie H, Iwata H, Muramatsu K, Yoshimoto N, Ito T, Ujiie I, Shimizu S, Sato-Matsumura KC, Shimizu H. Characteristics of IgG subclasses and complement deposition in BP230-type bullous pemphigoid. J Eur Acad Dermatol Venereol 2019; 33:595-600. [PMID: 30394605 DOI: 10.1111/jdv.15325] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2018] [Accepted: 10/04/2018] [Indexed: 11/26/2022]
Abstract
BACKGROUND Bullous pemphigoid (BP) is the most common autoimmune blistering disease. BP180 is the primary autoantigen of BP, and in a portion of BP cases, BP230 is the only target of autoantibodies. Such BP is called BP230-type BP. BP230-type BP tends to show milder clinical phenotypes than conventional BP, but the reason is unclear. The pathogenic roles of autoantibodies and complement activation have been shown in conventional BP, but the distribution of IgG subclasses and the degree of complement deposition in BP230-type BP remain unclear. OBJECTIVE To compare the distribution of IgG subclasses and the degree of complement deposition in BP230-type BP with those in conventional BP with autoantibodies to BP180 and BP230 (BP180-BP230-type BP). METHODS The diagnosis of BP was confirmed by the histopathology of the lesions, the deposition of IgG and complement in the perilesional skin and the presence of circulating autoantibodies to BP180 and BP230. The disease severity was determined by bullous pemphigoid disease area index. The deposition of IgG subclasses and complement deposition were examined by direct immunofluorescence of the perilesional skin in 6 BP230-type BP cases and 11 BP180-BP230-type BP cases. RESULTS Sixty seven percent of BP230-type BP cases show a mild clinical phenotype. All BP230-type BP cases and 82% of BP180-BP230-type BP cases were found to demonstrate the clear deposition of IgG4 at the basement membrane zone of skin specimens. Notably, the deposition of IgG1 and IgG3 was faint or negative in all of the BP230-type BP cases, whereas they were clearly detected in 91% and 64% of the BP180-BP230-type BP cases, respectively. The deposition of complement C3 tended to be weaker in BP230-type BP than in BP180-BP230-type BP. CONCLUSION The mild clinical phenotype of BP230-type BP may correlate with the weaker deposition of IgG1, IgG3 and complement in the skin lesions.
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Affiliation(s)
- M Zheng
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - H Ujiie
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - H Iwata
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - K Muramatsu
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - N Yoshimoto
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - T Ito
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - I Ujiie
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - S Shimizu
- Department of Dermatology, Sapporo City General Hospital, Sapporo, Japan
| | | | - H Shimizu
- Department of Dermatology, Hokkaido University Graduate School of Medicine, Sapporo, Japan
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Preformed C1q-binding Donor-specific Anti-HLA Antibodies and Graft Function After Kidney Transplantation. Transplant Proc 2018; 50:3460-3466. [DOI: 10.1016/j.transproceed.2018.07.033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 07/08/2018] [Accepted: 07/18/2018] [Indexed: 01/06/2023]
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Nagata K, Hara S, Nakayama Y, Higaki K, Sugihara H, Kuwamoto S, Matsushita M, Kato M, Tanio S, Ishiguro K, Hayashi K. Epstein-Barr Virus Lytic Reactivation Induces IgG4 Production by Host B Lymphocytes in Graves' Disease Patients and Controls: A Subset of Graves' Disease Is an IgG4-Related Disease-Like Condition. Viral Immunol 2018; 31:540-547. [PMID: 30222515 PMCID: PMC6205085 DOI: 10.1089/vim.2018.0042] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a newly recognized systemic fibroinflammatory disease with characteristic histological findings and high serum IgG4 levels. Epstein–Barr virus (EBV) is a persistent herpesvirus in B lymphocytes, and we previously reported EBV reactivation-induced Ig production. We showed that EBV reactivation induced the production of thyrotropin receptor antibodies, the causative antibodies of Graves' disease. In the present study, we investigated whether EBV reactivation induced IgG4 production and if EBV-positive B cells or IgG4-positive plasma cells are present in the thyroid tissues of Graves' disease patients with lymphoplasmacytic infiltration. EBV-encoded small RNA1 (EBER1) in situ hybridization and immunohistochemistry for IgG and IgG4 were performed on seven resected thyroid tissues with lymphoplasmacytic infiltration collected from the thyroids of 11 Graves' disease patients. We then cultured the lymphocytes of 13 Graves' disease patients and 14 controls and induced EBV reactivation to measure IgG4 levels in culture fluids. We detected EBER1-positive cells and IgG4-positive plasma cells in the same area of thyroid tissues. EBV-reactivated cells with IgG4 on their surface were observed in culture cells, and IgG4 production was detected in culture fluids. The IgG4/IgG percentage was higher than that in normal serum level. A subset of Graves' disease is an IgG4-RD-like condition, not an IgG4-RD. EBV reactivation stimulates IgG4 production, which may result in high serum IgG4 levels and promote IgG4-positive plasma cell infiltration. EBER1 needs to be examined when an increase in IgG4-positive plasma cell numbers is noted.
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Affiliation(s)
- Keiko Nagata
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Sayuri Hara
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Yuji Nakayama
- 2 Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University , Yonago, Japan
| | - Katsumi Higaki
- 2 Division of Functional Genomics, Research Center for Bioscience and Technology, Tottori University , Yonago, Japan
| | - Hirotsugu Sugihara
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Satoshi Kuwamoto
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Michiko Matsushita
- 3 Department of Pathobiological Science and Technology, School of Health Science, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Masako Kato
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Shunsuke Tanio
- 4 Division of Oral and Maxillofacial Biopathological Surgery, Department of Medicine of Sensory and Motor Organs, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Kiyosuke Ishiguro
- 5 Division of Organ Regeneration Surgery, Department of Surgery, Faculty of Medicine, Tottori University , Yonago, Japan
| | - Kazuhiko Hayashi
- 1 Division of Molecular Pathology, Department of Pathology, Faculty of Medicine, Tottori University , Yonago, Japan
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Langereis JD, van der Flier M, de Jonge MI. Limited Innovations After More Than 65 Years of Immunoglobulin Replacement Therapy: Potential of IgA- and IgM-Enriched Formulations to Prevent Bacterial Respiratory Tract Infections. Front Immunol 2018; 9:1925. [PMID: 30190722 PMCID: PMC6115500 DOI: 10.3389/fimmu.2018.01925] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 08/06/2018] [Indexed: 11/13/2022] Open
Abstract
Patients with primary immunoglobulin deficiency have lower immunoglobulin levels or decreased immunoglobulin function, which makes these patients more susceptible to bacterial infection. Most prevalent are the selective IgA deficiencies (~1:3,000), followed by common variable immune deficiency (~1:25,000). Agammaglobulinemia is less common (~1:400,000) and is characterized by very low or no immunoglobulin production resulting in a more severe disease phenotype. Therapy for patients with agammaglobulinemia mainly relies on prophylactic antibiotics and the use of IgG replacement therapy, which successfully reduces the frequency of invasive bacterial infections. Currently used immunoglobulin preparations contain only IgG. As a result, concurrent IgA and IgM deficiency persist in a large proportion of agammaglobulinemia patients. Especially patients with IgM deficiency remain at risk for recurrent infections at mucosal surfaces, which includes the respiratory tract. IgA and IgM have multiple functions in the protection against bacterial infections at the mucosal surface. Because of their multimeric structure, both IgA and IgM are able to agglutinate bacteria efficiently. Agglutination allows for entrapment of bacteria in mucus that increases clearance from the respiratory tract. IgA is also important for blocking bacterial adhesion by interfering with bacterial adhesion receptors. IgM in its place is very well capable of activating complement, therefore, it is thought to be important in complement-mediated protection at the mucosal surface. The purpose of this Mini Review is to highlight the latest advances regarding IgA- and IgM-enriched immunoglobulin replacement therapy. We describe the different IgA- and IgM-enriched IgG formulations, their possible modes of action and potential to protect against respiratory tract infections in patients with primary immunoglobulin deficiencies.
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Affiliation(s)
- Jeroen D. Langereis
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
- Radboud Center for Infectious Diseases, Nijmegen, Netherlands
| | - Michiel van der Flier
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
- Radboud Center for Infectious Diseases, Nijmegen, Netherlands
- Pediatric Infectious Diseases and Immunology, Amalia Children's Hospital, Nijmegen, Netherlands
- Expertise Center for Immunodeficiency and Autoinflammation (REIA), Radboudumc, Nijmegen, Netherlands
| | - Marien I. de Jonge
- Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Nijmegen, Netherlands
- Radboud Center for Infectious Diseases, Nijmegen, Netherlands
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Kauder SE, Kuo TC, Harrabi O, Chen A, Sangalang E, Doyle L, Rocha SS, Bollini S, Han B, Sim J, Pons J, Wan HI. ALX148 blocks CD47 and enhances innate and adaptive antitumor immunity with a favorable safety profile. PLoS One 2018; 13:e0201832. [PMID: 30133535 PMCID: PMC6104973 DOI: 10.1371/journal.pone.0201832] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 07/23/2018] [Indexed: 02/06/2023] Open
Abstract
CD47 is a widely expressed cell surface protein that functions as an immune checkpoint in cancer. When expressed by tumor cells, CD47 can bind SIRPα on myeloid cells, leading to suppression of tumor cell phagocytosis and other innate immune functions. CD47-SIRPα signaling has also been implicated in the suppression of adaptive antitumor responses, but the relevant cellular functions have yet to be elucidated. Therapeutic blockade of the CD47 pathway may stimulate antitumor immunity and improve cancer therapy. To this end, a novel CD47-blocking molecule, ALX148, was generated by fusing a modified SIRPα D1 domain to an inactive human IgG1 Fc. ALX148 binds CD47 from multiple species with high affinity, inhibits wild type SIRPα binding, and enhances phagocytosis of tumor cells by macrophages. ALX148 has no effect on normal human blood cells in vitro or on blood cell parameters in rodent and non-human primate studies. Across several murine tumor xenograft models, ALX148 enhanced the antitumor activity of different targeted antitumor antibodies. Additionally, ALX148 enhanced the antitumor activity of multiple immunotherapeutic antibodies in syngeneic tumor models. These studies revealed that CD47 blockade with ALX148 induces multiple responses that bridge innate and adaptive immunity. ALX148 stimulates antitumor properties of innate immune cells by promoting dendritic cell activation, macrophage phagocytosis, and a shift of tumor-associated macrophages toward an inflammatory phenotype. ALX148 also stimulated the antitumor properties of adaptive immune cells, causing increased T cell effector function, pro-inflammatory cytokine production, and a reduction in the number of suppressive cells within the tumor microenvironment. Taken together, these results show that ALX148 binds and blocks CD47 with high affinity, induces a broad antitumor immune response, and has a favorable safety profile.
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Affiliation(s)
| | - Tracy C. Kuo
- ALX Oncology, Burlingame, CA, United States of America
| | - Ons Harrabi
- ALX Oncology, Burlingame, CA, United States of America
| | - Amy Chen
- ALX Oncology, Burlingame, CA, United States of America
| | | | - Laura Doyle
- ALX Oncology, Burlingame, CA, United States of America
| | - Sony S. Rocha
- ALX Oncology, Burlingame, CA, United States of America
| | | | - Bora Han
- ALX Oncology, Burlingame, CA, United States of America
| | - Janet Sim
- ALX Oncology, Burlingame, CA, United States of America
| | - Jaume Pons
- ALX Oncology, Burlingame, CA, United States of America
| | - Hong I. Wan
- ALX Oncology, Burlingame, CA, United States of America
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Klaus T, Bereta J. CH2 Domain of Mouse IgG3 Governs Antibody Oligomerization, Increases Functional Affinity to Multivalent Antigens and Enhances Hemagglutination. Front Immunol 2018; 9:1096. [PMID: 29875771 PMCID: PMC5974032 DOI: 10.3389/fimmu.2018.01096] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2018] [Accepted: 05/02/2018] [Indexed: 01/06/2023] Open
Abstract
Mouse IgG3 is highly protective against several life-threatening bacteria. This isotype is the only one among mouse IgGs that forms non-covalent oligomers, has increased functional affinity to polyvalent antigens, and efficiently agglutinates erythrocytes. IgG3 also triggers the complement cascade. The high efficacy of protection after passive immunization with IgG3 is correlated with the unique properties of this isotype. Although the features of IgG3 are well documented, their molecular basis remains elusive. Based on functional analyses of IgG1/IgG3 hybrid molecules with swapped constant domains, we identified IgG3-derived CH2 domain as a major determinant of antibody oligomerization and increased functional affinity to a multivalent antigen. The CH2 domain was also crucial for efficient hemagglutination triggered by IgG3 and was indispensable for complement cascade activation. This domain is glycosylated and atypically charged. A mutational analysis based on molecular models of CH2 domain charge distribution indicated that the functional affinity was influenced by the specific charge location. N-glycans were essential for CH2-dependent enhancement of hemagglutination and complement activation. Oligomerization was independent of CH2 charge and glycosylation. We also verified that known C1q-binding motifs are functional in mouse IgG3 but not in IgG1 framework. We generated for the first time a gain-of-function antibody with properties transferred from IgG3 into IgG1 by replacing the CH2 domain. Finding that the CH2 domain of IgG3 governs unique properties of this isotype is likely to open an avenue toward the generation of IgG3-inspired antibodies that will be protective against existing or emerging lethal pathogens.
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Affiliation(s)
- Tomasz Klaus
- Laboratory of Monoclonal Antibodies, Małopolska Centre of Biotechnology, Jagiellonian University, Kraków, Poland.,Department of Cell Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
| | - Joanna Bereta
- Department of Cell Biochemistry, Faculty of Biochemistry, Biophysics and Biotechnology, Jagiellonian University, Kraków, Poland
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Zhou W, Lin S, Chen R, Liu J, Li Y. Characterization of antibody-C1q interactions by Biolayer Interferometry. Anal Biochem 2018; 549:143-148. [DOI: 10.1016/j.ab.2018.03.022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2017] [Revised: 02/20/2018] [Accepted: 03/21/2018] [Indexed: 12/17/2022]
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Bouquegneau A, Loheac C, Aubert O, Bouatou Y, Viglietti D, Empana J, Ulloa C, Hassan Murad M, Legendre C, Glotz D, Jackson AM, Zeevi A, Schaub S, Taupin J, Reed EF, Friedewald JJ, Tyan DB, Süsal C, Shapiro R, Woodle ES, Hidalgo LG, O’Leary J, Montgomery RA, Kobashigawa J, Jouven X, Jabre P, Lefaucheur C, Loupy A. Complement-activating donor-specific anti-HLA antibodies and solid organ transplant survival: A systematic review and meta-analysis. PLoS Med 2018; 15:e1002572. [PMID: 29799874 PMCID: PMC5969739 DOI: 10.1371/journal.pmed.1002572] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 04/26/2018] [Indexed: 12/19/2022] Open
Abstract
BACKGROUND Anti-human leukocyte antigen donor-specific antibodies (anti-HLA DSAs) are recognized as a major barrier to patients' access to organ transplantation and the major cause of graft failure. The capacity of circulating anti-HLA DSAs to activate complement has been suggested as a potential biomarker for optimizing graft allocation and improving the rate of successful transplantations. METHODS AND FINDINGS To address the clinical relevance of complement-activating anti-HLA DSAs across all solid organ transplant patients, we performed a meta-analysis of their association with transplant outcome through a systematic review, from inception to January 31, 2018. The primary outcome was allograft loss, and the secondary outcome was allograft rejection. A comprehensive search strategy was conducted through several databases (Medline, Embase, Cochrane, and Scopus). A total of 5,861 eligible citations were identified. A total of 37 studies were included in the meta-analysis. Studies reported on 7,936 patients, including kidney (n = 5,991), liver (n = 1,459), heart (n = 370), and lung recipients (n = 116). Solid organ transplant recipients with circulating complement-activating anti-HLA DSAs experienced an increased risk of allograft loss (pooled HR 3.09; 95% CI 2.55-3.74, P = 0.001; I2 = 29.3%), and allograft rejection (pooled HR 3.75; 95% CI: 2.05-6.87, P = 0.001; I2 = 69.8%) compared to patients without complement-activating anti-HLA DSAs. The association between circulating complement-activating anti-HLA DSAs and allograft failure was consistent across all subgroups and sensitivity analyses. Limitations of the study are the observational and retrospective design of almost all included studies, the higher proportion of kidney recipients compared to other solid organ transplant recipients, and the inclusion of fewer studies investigating allograft rejection. CONCLUSIONS In this study, we found that circulating complement-activating anti-HLA DSAs had a significant deleterious impact on solid organ transplant survival and risk of rejection. The detection of complement-activating anti-HLA DSAs may add value at an individual patient level for noninvasive biomarker-guided risk stratification. TRIAL REGISTRATION National Clinical Trial protocol ID: NCT03438058.
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Affiliation(s)
- Antoine Bouquegneau
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Nephrology, Dialysis and Transplantation, CHU de Liège, Liège, Belgium
| | - Charlotte Loheac
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
| | - Olivier Aubert
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Kidney Transplantation, Necker Hospital, Paris Descartes University, and Assistance Publique–Hôpitaux de Paris (AP–HP), Paris, France
| | - Yassine Bouatou
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Division of Nephrology, Geneva University Hospitals, Geneva, Switzerland
| | - Denis Viglietti
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Nephrology and Kidney Transplantation, Saint–Louis Hospital, Paris Diderot University, AP–HP, Paris, France
| | - Jean–Philippe Empana
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
| | - Camilo Ulloa
- Hospital Barros Luco Trudeau, Santiago, Chile et Clinica Alemana de Santiago, Chile
| | - Mohammad Hassan Murad
- Mayo Clinic Evidence–based Practice Center, Mayo Clinic, Rochester, Minnesota, United States of America
| | - Christophe Legendre
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Kidney Transplantation, Necker Hospital, Paris Descartes University, and Assistance Publique–Hôpitaux de Paris (AP–HP), Paris, France
| | - Denis Glotz
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Nephrology and Kidney Transplantation, Saint–Louis Hospital, Paris Diderot University, AP–HP, Paris, France
| | - Annette M. Jackson
- Immunogenetics Laboratory, Johns Hopkins University School of Medicine, Baltimore, Maryland, United States of America
| | - Adriana Zeevi
- Department of Pathology, Surgery and Immunology at University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania, United States of America
| | - Stephan Schaub
- Clinic for Transplantation Immunology and Nephrology, University Hospital Basel, Basel, Switzerland
| | - Jean–Luc Taupin
- Department of Immunology and Histocompatibility, CHU Paris–GH St–Louis Lariboisière, Paris, France
| | - Elaine F. Reed
- Department of Pathology and Laboratory Medicine, UCLA Immunogenetics Center, David Geffen School of Medicine, University of California, Los Angeles, California, United States of America
| | - John J. Friedewald
- Northwestern University Feinberg School of Medicine, Comprehensive Transplant Center, Division of Transplant Surgery, Chicago, Illinois, United states of America
| | - Dolly B. Tyan
- Division of Nephrology, Department of Medicine, Stanford University, Stanford, California, United States of America
| | - Caner Süsal
- Institute of Immunology, Heidelberg University, Department of Transplantation Immunology, Heidelberg, Germany
| | - Ron Shapiro
- Kidney/Pancreas Transplant Program, Mount Sinai Hospital, Recanati Miller Transplantation Institute, New York, New York, United States of America
| | - E. Steve Woodle
- Division of Transplantation, Department of Surgery, and Division of Hematology and Oncology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio, United States of America
| | - Luis G. Hidalgo
- Department of Laboratory Medicine and Pathology and Alberta Transplant Applied Genomics Center, Edmonton, Alberta, Canada
| | - Jacqueline O’Leary
- Annette C. & Harold C. Simmons Transplant Institute, Baylor University Medical Center, Dallas, Texas, United States of America
| | - Robert A. Montgomery
- The NYU Transplant Institute, New York University Langone Medical Center, New York, New York, United States of America
| | - Jon Kobashigawa
- Cedars–Sinai Heart Institute, Los Angeles, California, United States of America
| | - Xavier Jouven
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Cardiology and Global Health Unit European Georges Pompidou Hospital, Paris
| | - Patricia Jabre
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- SAMU of Paris, Necker Hospital Paris, France
- Paris Descartes University, Paris, France
- AP–HP, Paris, France
| | - Carmen Lefaucheur
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Nephrology and Kidney Transplantation, Saint–Louis Hospital, Paris Diderot University, AP–HP, Paris, France
| | - Alexandre Loupy
- Paris Translational Research Center for Organ Transplantation INSERM Unit 970, Paris, France
- Department of Kidney Transplantation, Necker Hospital, Paris Descartes University, and Assistance Publique–Hôpitaux de Paris (AP–HP), Paris, France
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Changes in N-glycans of IgG4 and its relationship with the existence of hypocomplementemia and individual organ involvement in patients with IgG4-related disease. PLoS One 2018; 13:e0196163. [PMID: 29672582 PMCID: PMC5908088 DOI: 10.1371/journal.pone.0196163] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 04/06/2018] [Indexed: 12/24/2022] Open
Abstract
Background Although increased serum IgG4 level and tissue infiltration of IgG4-positive cells are key events in IgG4-related disease (IgG4RD), and nearly half of IgG4RD patients show hypocomplementemia, the role of IgG4 in the pathogenesis of IgG4RD remains unclear. Many reports show that altered IgG glycosylation, especially IgG with agalactosylated N-linked glycan (G0 N-glycan), have proinflammatory roles including complement activation, implicated in the pathogenesis of various inflammatory diseases. This study determined the concentration of N-linked glycans (N-glycan) released from serum IgG4 in IgG4RD patients and compared the difference of glycosylation changes to those in healthy controls. We also compared the concentration of each IgG4 glycoform between patients with and without hypocomplementemia and individual organ involvement (kidney, pancreas, lymph node) in IgG4RD. Methods We collected sera from 12 IgG4RD patients and 8 healthy controls. IgG4 was isolated from sera via Melon™ Gel IgG Spin Purification Kit followed by Capture Select IgG4 (Hu) Affinity Matrix. IgG4 N-glycans were analyzed by S-BIO GlycanMap® Xpress methodology. Results Significant increases of IgG4 G0 N-glycan and IgG4 fucosylated N-glycan (F1 N-glycan) concentrations were observed in IgG4RD compared with healthy controls. Although we observed decreased levels of IgG4 F0 glycan in IgG4RD with hypocomplementemia, there were no significant differences in the galactosylation and sialyation of IgG4 N-glycans. Furthermore, there were no significant differences in the glycosylation of IgG4 N-glycans between patients with and without individual organ involvement of IgG4RD. Conclusions Although IgG4 has anti-inflammatory properties, IgG4 G0 and F1 glycans were increased in patients with IgG4RD. Our results suggest that decreased galactosylation of IgG4 is not related to complement activation and the differences of individual organ involvement in IgG4RD. IgG4 fucosylation change may be related to complement activation in IgG4RD. Further investigation is needed to clarify the role of IgG4 in IgG4RD.
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