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Hui GK, Gao X, Gor J, Lu J, Sun PD, Perkins SJ. The solution structure of the unbound IgG Fc receptor CD64 resembles its crystal structure: Implications for function. PLoS One 2023; 18:e0288351. [PMID: 37733670 PMCID: PMC10513344 DOI: 10.1371/journal.pone.0288351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Accepted: 06/23/2023] [Indexed: 09/23/2023] Open
Abstract
FcγRI (CD64) is the only high-affinity Fcγ receptor found on monocytes, macrophages, eosinophils, neutrophils and dendritic cells. It binds immunoglobulin G (IgG) antibody-antigen complexes at its Fc region to trigger key immune responses. CD64 contains three immunoglobulin-fold extracellular domains (D1, D2 and D3) and a membrane-spanning region. Despite the importance of CD64, no solution structure for this is known to date. To investigate this, we used analytical ultracentrifugation, small-angle X-ray scattering, and atomistic modelling. Analytical ultracentrifugation revealed that CD64 was monomeric with a sedimentation coefficient s020,w of 2.53 S, together with some dimer. Small-angle X-ray scattering showed that its radius of gyration RG was 3.3-3.4 nm and increased at higher concentrations to indicate low dimerization. Monte Carlo modelling implemented in the SASSIE-web package generated 279,162 physically-realistic trial CD64 structures. From these, the scattering best-fit models at the lowest measured concentrations that minimised dimers revealed that the D1, D2 and D3 domains were structurally similar to those seen in three CD64 crystal structures, but showed previously unreported flexibility between D1, D2 and D3. Despite the limitations of the scattering data, the superimposition of the CD64 solution structures onto crystal structures of the IgG Fc-CD64 complex showed that the CD64 domains do not sterically clash with the IgG Fc region, i.e. the solution structure of CD64 was sufficiently compact to allow IgG to bind to its high-affinity Fcγ receptor. This improved understanding may result in novel approaches to inhibit CD64 function, and opens the way for the solution study of the full-length CD64-IgG complex.
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Affiliation(s)
- Gar Kay Hui
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, United Kingdom
| | - Xin Gao
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, United Kingdom
| | - Jayesh Gor
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, United Kingdom
| | - Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, Maryland, United States of America
| | - Peter D. Sun
- Structural Immunology Section, Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institute of Health, Rockville, Maryland, United States of America
| | - Stephen J. Perkins
- Department of Structural and Molecular Biology, Darwin Building, University College London, London, United Kingdom
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2
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Liu Y, Caterina MJ, Qu L. Sensory Neuron Expressed FcγRI Mediates Postinflammatory Arthritis Pain in Female Mice. Front Immunol 2022; 13:889286. [PMID: 35833115 PMCID: PMC9271677 DOI: 10.3389/fimmu.2022.889286] [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: 03/04/2022] [Accepted: 06/01/2022] [Indexed: 11/13/2022] Open
Abstract
Persistent arthritis pain after resolution of joint inflammation represents a huge health burden in patients with rheumatoid arthritis (RA). However, the underling mechanisms are poorly understood. We and other groups recently revealed that FcγRI, a key immune receptor, is functionally expressed in joint nociceptors. Thus, we investigated a potential role of sensory neuron expressed FcγRI in postinflammatory arthritis pain in a mouse model of collagen antibody-induced arthritis (CAIA). Here, we show that global deletion of Fcgr1 significantly attenuated mechanical hyperalgesia in the ankle and hind paw of female mice in both inflammatory and postinflammatory phases of CAIA. No obvious differences in cartilage destruction were observed after resolution of joint inflammation between genotypes. In situ hybridization (ISH) revealed that a larger proportion of dorsal root ganglion (DRG) neurons expressed Fcgr1 mRNA signal in the late phase of CAIA. Conditional deletion of Fcgr1 in primary sensory neurons produced similar analgesic effects without affecting joint swelling. Knockdown of Fcgr1 expression within DRG in the postinflammatory phase of CAIA alleviated persistent pain. Inflammation within DRG after resolution of joint inflammation in the CAIA model was evidenced by T cell and neutrophil infiltration and upregulated mRNA expression of numerous inflammatory mediators. Yet, such changes were not altered by genetic deletion of Fcgr1. We suggest that neuroinflammation within the DRG after resolution of joint inflammation might upregulate FcγRI signaling in DRG neurons. Sensory neuron expressed FcγRI thus merits exploration as a potential target for the treatment of arthritis pain that persists in RA patients in remission.
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Affiliation(s)
- Yan Liu
- Department of Neurosurgery, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Michael J. Caterina
- Department of Neurosurgery, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD, United States
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, United States
- Department of Biological Chemistry, Johns Hopkins School of Medicine, Baltimore, MD, United States
| | - Lintao Qu
- Department of Neurosurgery, Neurosurgery Pain Research Institute, Johns Hopkins School of Medicine, Baltimore, MD, United States
- *Correspondence: Lintao Qu,
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3
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Chalayer E, Gramont B, Zekre F, Goguyer-Deschaumes R, Waeckel L, Grange L, Paul S, Chung AW, Killian M. Fc receptors gone wrong: A comprehensive review of their roles in autoimmune and inflammatory diseases. Autoimmun Rev 2021; 21:103016. [PMID: 34915182 DOI: 10.1016/j.autrev.2021.103016] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 12/08/2021] [Indexed: 12/16/2022]
Abstract
Systemic autoimmune and inflammatory diseases have a complex and only partially known pathophysiology with various abnormalities involving all the components of the immune system. Among these components, antibodies, and especially autoantibodies are key elements contributing to autoimmunity. The interaction of antibody fragment crystallisable (Fc) and several distinct receptors, namely Fc receptors (FcRs), have gained much attention during the recent years, with possible major therapeutic perspectives for the future. The aim of this review is to comprehensively describe the known roles for FcRs (activating and inhibitory FcγRs, neonatal FcR [FcRn], FcαRI, FcεRs, Ro52/tripartite motif containing 21 [Ro52/TRIM21], FcδR, and the novel Fc receptor-like [FcRL] family) in systemic autoimmune and inflammatory disorders, namely rheumatoid arthritis, Sjögren's syndrome, systemic lupus erythematosus, systemic sclerosis, idiopathic inflammatory myopathies, mixed connective tissue disease, Crohn's disease, ulcerative colitis, immunoglobulin (Ig) A vasculitis, Behçet's disease, Kawasaki disease, IgG4-related disease, immune thrombocytopenia, autoimmune hemolytic anemia, antiphospholipid syndrome and heparin-induced thrombocytopenia.
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Affiliation(s)
- Emilie Chalayer
- Department of Hematology and Cell Therapy, Institut de Cancérologie Lucien Neuwirth, Saint-Etienne, France; INSERM U1059-Sainbiose, dysfonction vasculaire et hémostase, Université de Lyon, Saint-Etienne, France
| | - Baptiste Gramont
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Internal Medicine, Saint-Etienne University Hospital, Saint-Etienne, France
| | - Franck Zekre
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Pediatrics, Saint-Etienne University Hospital, Saint-Etienne, France
| | - Roman Goguyer-Deschaumes
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France
| | - Louis Waeckel
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Immunology, Saint-Etienne University Hospital, Saint-Etienne, France
| | - Lucile Grange
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Internal Medicine, Saint-Etienne University Hospital, Saint-Etienne, France
| | - Stéphane Paul
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Immunology, Saint-Etienne University Hospital, Saint-Etienne, France
| | - Amy W Chung
- The Peter Doherty Institute for Infection and Immunity, The University of Melbourne, Melbourne, Victoria, Australia
| | - Martin Killian
- CIRI - Centre International de Recherche en Infectiologie, Team GIMAP, Université de Lyon, Université Jean Monnet, Université Claude Bernard Lyon 1, INSERM, U1111, CNRS, UMR530, F42023 Saint-Etienne, France; Department of Internal Medicine, Saint-Etienne University Hospital, Saint-Etienne, France.
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El-Gendy H, Hawass SED, Awad M, Mohsen MA, Amin M, Abdalla HA, Fouad S, Lotfy A. Comparative study between human mesenchymal stem cells and etanercept as immunomodulatory agents in rat model of rheumatoid arthritis. Immunol Res 2021; 68:255-268. [PMID: 32734446 DOI: 10.1007/s12026-020-09132-w] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
To compare human adipose tissue mesenchymal stem cells (AT-MSCs) and etanercept as immunomodulatory agents for collagen-induced arthritis (CIA). CIA was induced by rats' immunization with collagen type II (CII) in complete Freund's adjuvant in days 0 and 7. Before the onset of CIA, prevention group received five doses of AT-MSCS intraperitoneally. After establishment of arthritis, rats received either five doses of AT-MSCs or phosphate-buffered saline (PBS) intraperitoneally or six doses of etanercept subcutaneously. Clinical and histopathological evaluation were performed in all groups; serum levels of tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), and anti-collagen II were assessed by enzyme-linked immunosorbent assay (ELISA). A total percent of autoreactive T and regulatory T (Treg) cells were quantified using spleen immune histochemical analysis. AT-MSCs were able to delay the onset of CIA, suppress the ongoing clinical and histopathological signs, decrease serum levels of TNF-α and anti-collagen type II, and downregulate the autoreactive T cells as etanercept. AT-MSCs were more potent in Treg cells upregulation, producing high serum levels of IL10. AT-MSCs might have a therapeutic effect in CIA via their potency in immune cell education, representing an effective new promising approach in rheumatoid arthritis in human.
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Affiliation(s)
- Heba El-Gendy
- Department of Rheumatology and Rehabilitation, Faculty of Medicine, Mansoura University, Mansoura, Egypt.
| | - Salah El-Deen Hawass
- Department of Rheumatology and Rehabilitation, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Manal Awad
- Department of Rheumatology and Rehabilitation, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Mona Ahmad Mohsen
- Department of Rheumatology and Rehabilitation, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Maha Amin
- Department of Pathology, Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | | | - Samah Fouad
- Medical Experimental Research Centre , Faculty of Medicine, Mansoura University, Mansoura, Egypt
| | - Ahmed Lotfy
- eBiotechnology and Life Sciences Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University, Beni-Suef, Egypt
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Lacagnina MJ, Heijnen CJ, Watkins LR, Grace PM. Autoimmune regulation of chronic pain. Pain Rep 2021; 6:e905. [PMID: 33981931 PMCID: PMC8108590 DOI: 10.1097/pr9.0000000000000905] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2020] [Revised: 11/19/2020] [Accepted: 01/19/2021] [Indexed: 01/24/2023] Open
Abstract
Chronic pain is an unpleasant and debilitating condition that is often poorly managed by existing therapeutics. Reciprocal interactions between the nervous system and the immune system have been recognized as playing an essential role in the initiation and maintenance of pain. In this review, we discuss how neuroimmune signaling can contribute to peripheral and central sensitization and promote chronic pain through various autoimmune mechanisms. These pathogenic autoimmune mechanisms involve the production and release of autoreactive antibodies from B cells. Autoantibodies-ie, antibodies that recognize self-antigens-have been identified as potential molecules that can modulate the function of nociceptive neurons and thereby induce persistent pain. Autoantibodies can influence neuronal excitability by activating the complement pathway; by directly signaling at sensory neurons expressing Fc gamma receptors, the receptors for the Fc fragment of immunoglobulin G immune complexes; or by binding and disrupting ion channels expressed by nociceptors. Using examples primarily from rheumatoid arthritis, complex regional pain syndrome, and channelopathies from potassium channel complex autoimmunity, we suggest that autoantibody signaling at the central nervous system has therapeutic implications for designing novel disease-modifying treatments for chronic pain.
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Affiliation(s)
- Michael J. Lacagnina
- Laboratories of Neuroimmunology, Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Cobi J. Heijnen
- Laboratories of Neuroimmunology, Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Linda R. Watkins
- Department of Psychology and Neuroscience, Center for Neuroscience, University of Colorado, Boulder, CO, USA
| | - Peter M. Grace
- Laboratories of Neuroimmunology, Department of Symptom Research, University of Texas MD Anderson Cancer Center, Houston, TX, USA
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6
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The prospects for targeting FcR as a novel therapeutic strategy in rheumatoid arthritis. Biochem Pharmacol 2020; 183:114360. [PMID: 33301760 DOI: 10.1016/j.bcp.2020.114360] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Revised: 12/03/2020] [Accepted: 12/03/2020] [Indexed: 01/05/2023]
Abstract
Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial membrane hyperplasia, infiltration of inflammatory cells and bone tissue destruction. Although there have been many measures taken for RA therapy in recent years, they are not sufficiently safe or effective. Thus, it is very important to develop new drugs and slow down damage to other healthy organs in the case of RA. Lately, immunoglobulin Fc receptors (FcRs), such as the IgG Fc receptor (FcγR), IgA Fc receptor (FcαR), and IgD Fc receptor (FcδR), have been found to be involved in inducing or suppressing arthritis. FcRs interacting with immune complexes (ICs) are a key factor in the etiopathogenesis of RA. Therefore, an increasing number of methodsfor the targeted treatment of RA with FcRs are emerging, such as recombinant soluble FcγRs, recombinant multimeric Fc fragments and monoclonal antibodies, and have been demonstrated to significantly improve RA symptoms. Simultaneously, certain kinases involved in the downstream signaling of FcRs can also be a target for the treatment of RA, such as Syk and Btk inhibitors. An overview of these FcRs is provided in this review, including a description of FcR-related functions, signaling pathways, and potential FcR-targeting molecules for RA therapy. To date, the initial results of those developed FcR-targeting molecules have been promising. With this, FcRs might offer a better alternative to RA medication. Additionally, further pharmacological characterization and a better understanding of the unique mechanisms of FcR-targeting molecules are necessary.
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7
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Wang L, Jiang X, Zheng Q, Jeon SM, Chen T, Liu Y, Kulaga H, Reed R, Dong X, Caterina MJ, Qu L. Neuronal FcγRI mediates acute and chronic joint pain. J Clin Invest 2019; 129:3754-3769. [PMID: 31211699 DOI: 10.1172/jci128010] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Although joint pain in rheumatoid arthritis (RA) is conventionally thought to result from inflammation, arthritis pain and joint inflammation are at least partially uncoupled. This suggests that additional pain mechanisms in RA remain to be explored. Here we show that FcγRI, an immune receptor for IgG immune complex (IgG-IC), is expressed in a subpopulation of joint sensory neurons and that, under naïve conditions, FcγRI crosslinking by IgG-IC directly activates the somata and peripheral terminals of these neurons to evoke acute joint hypernociception without obvious concurrent joint inflammation. These effects were diminished in both global and sensory neuron-specific Fcgr1 knockout mice. In murine models of inflammatory arthritis, FcγRI signaling was upregulated in joint sensory neurons. Acute blockade or global genetic deletion of Fcgr1 significantly attenuated arthritis pain and hyperactivity of joint sensory neurons without measurably altering joint inflammation. Conditional deletion of Fcgr1 in sensory neurons produced similar analgesic effects in these models. We therefore suggest that FcγRI expressed in sensory neurons contributes to arthritis pain independently of its functions in inflammatory cells. These findings expand our understanding of the immunosensory capabilities of sensory neurons and imply that neuronal FcγRI merits consideration as a target for treating RA pain.
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Affiliation(s)
- Li Wang
- Department of Neurosurgery and Neurosurgery Pain Research Institute
| | - Xiaohua Jiang
- Department of Neurosurgery and Neurosurgery Pain Research Institute
| | - Qin Zheng
- Solomon H. Snyder Department of Neuroscience
| | - Sang-Min Jeon
- Department of Neurosurgery and Neurosurgery Pain Research Institute
| | - Tiane Chen
- Department of Neurosurgery and Neurosurgery Pain Research Institute
| | - Yan Liu
- Department of Neurosurgery and Neurosurgery Pain Research Institute
| | | | - Randall Reed
- Department of Molecular Biology and Genetics, and
| | | | - Michael J Caterina
- Department of Neurosurgery and Neurosurgery Pain Research Institute.,Solomon H. Snyder Department of Neuroscience.,Department of Biological Chemistry, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
| | - Lintao Qu
- Department of Neurosurgery and Neurosurgery Pain Research Institute
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8
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Anania JC, Chenoweth AM, Wines BD, Hogarth PM. The Human FcγRII (CD32) Family of Leukocyte FcR in Health and Disease. Front Immunol 2019; 10:464. [PMID: 30941127 PMCID: PMC6433993 DOI: 10.3389/fimmu.2019.00464] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 02/21/2019] [Indexed: 12/15/2022] Open
Abstract
FcγRs have been the focus of extensive research due to their key role linking innate and humoral immunity and their implication in both inflammatory and infectious disease. Within the human FcγR family FcγRII (activatory FcγRIIa and FcγRIIc, and inhibitory FcγRIIb) are unique in their ability to signal independent of the common γ chain. Through improved understanding of the structure of these receptors and how this affects their function we may be able to better understand how to target FcγR specific immune activation or inhibition, which will facilitate in the development of therapeutic monoclonal antibodies in patients where FcγRII activity may be desirable for efficacy. This review is focused on roles of the human FcγRII family members and their link to immunoregulation in healthy individuals and infection, autoimmunity and cancer.
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Affiliation(s)
- Jessica C Anania
- Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.,Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Alicia M Chenoweth
- Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.,Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, VIC, Australia
| | - Bruce D Wines
- Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.,Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Department of Pathology, The University of Melbourne, Melbourne, VIC, Australia
| | - P Mark Hogarth
- Centre for Biomedical Research, Burnet Institute, Melbourne, VIC, Australia.,Department of Immunology and Pathology, Central Clinical School, Monash University, Melbourne, VIC, Australia.,Department of Pathology, The University of Melbourne, Melbourne, VIC, Australia
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9
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Hayes JM, Wormald MR, Rudd PM, Davey GP. Fc gamma receptors: glycobiology and therapeutic prospects. J Inflamm Res 2016; 9:209-219. [PMID: 27895507 PMCID: PMC5118039 DOI: 10.2147/jir.s121233] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Therapeutic antibodies hold great promise for the treatment of cancer and autoimmune diseases, and developments in antibody–drug conjugates and bispecific antibodies continue to enhance treatment options for patients. Immunoglobulin (Ig) G antibodies are proteins with complex modifications, which have a significant impact on their function. The most important of these modifications is glycosylation, the addition of conserved glycans to the antibody Fc region, which is critical for its interaction with the immune system and induction of effector activities such as antibody-dependent cell cytotoxicity, complement activation and phagocytosis. Communication of IgG antibodies with the immune system is controlled and mediated by Fc gamma receptors (FcγRs), membrane-bound proteins, which relay the information sensed and gathered by antibodies to the immune system. These receptors are also glycoproteins and provide a link between the innate and adaptive immune systems. Recent information suggests that this receptor glycan modification is also important for the interaction with antibodies and downstream immune response. In this study, the current knowledge on FcγR glycosylation is discussed, and some insight into its role and influence on the interaction properties with IgG, particularly in the context of biotherapeutics, is provided. For the purpose of this study, other Fc receptors such as FcαR, FcεR or FcRn are not discussed extensively, as IgG-based antibodies are currently the only therapeutic antibody-based products on the market. In addition, FcγRs as therapeutics and therapeutic targets are discussed, and insight into and comment on the therapeutic aspects of receptor glycosylation are provided.
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Affiliation(s)
- Jerrard M Hayes
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College, Dublin, Ireland
| | - Mark R Wormald
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford, UK
| | - Pauline M Rudd
- NIBRT Glycoscience Group, National Institute for Bioprocessing, Research and Training, Dublin, Ireland
| | - Gavin P Davey
- School of Biochemistry and Immunology, Trinity Biomedical Sciences Institute, Trinity College, Dublin, Ireland
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10
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Harnessing Fc receptor biology in the design of therapeutic antibodies. Curr Opin Immunol 2016; 40:78-87. [DOI: 10.1016/j.coi.2016.03.005] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/14/2016] [Accepted: 03/15/2016] [Indexed: 02/04/2023]
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Matt P, Lindqvist U, Kleinau S. Up-regulation of CD64-expressing monocytes with impaired FcγR function reflects disease activity in polyarticular psoriatic arthritis. Scand J Rheumatol 2015; 44:464-73. [PMID: 26084203 DOI: 10.3109/03009742.2015.1020864] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
OBJECTIVES The aim of this study was to assess monocyte Fc receptor (FcR) status and function in patients with active psoriatic arthritis (PsA) in relation to healthy controls (HC) and to disease activity. METHOD The study population comprised 23 patients with active polyarticular PsA and 33 age- and gender-matched HC. Immunoglobulin (Ig) levels, inflammatory laboratory parameters, patient-reported outcomes of joint disease activity, skin scoring (Psoriasis Area and Severity Index, PASI), and joint status were determined in the patients. Monocytes were analysed for the expression of FcRs for IgG (FcγR) class I (CD64), IIa (CD32a), IIb (CD32b), and III (CD16), the FcR for IgA (FcαR) (CD89), and surface-bound IgG. The monocytic FcγR function was assessed by evaluating IgG immune complex (IC) binding and tumour necrosis factor (TNF)-α production following IgG-IC stimulation. The monocytes were further subdivided and analysed according to their CD14 and CD16 expression. RESULTS The PsA patients presented elevated serum levels of IgG1, 2, and 3 and increased numbers of CD64(+) monocytes. Furthermore, the PsA monocytes exhibited increased cell-bound IgG, and the FcγR function was affected in terms of reduced IgG-IC-mediated TNF-α release. These findings correlated significantly with different markers of joint disease activity. PsA was also accompanied by an increase in the CD16 low-expressing monocyte subset. CONCLUSIONS An intensified humoral immune response affects monocytes and their FcR status in active polyarticular PsA. The up-regulated CD64(+) monocytes seem to be have an important role in psoriatic joint inflammation. These cells may prove to be a useful target in future PsA therapeutic interventions.
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Affiliation(s)
- P Matt
- a Department of Medical Sciences, Rheumatology , Uppsala University , Sweden.,b Department of Cellular and Molecular Biology , Uppsala University , Sweden
| | - U Lindqvist
- a Department of Medical Sciences, Rheumatology , Uppsala University , Sweden
| | - S Kleinau
- b Department of Cellular and Molecular Biology , Uppsala University , Sweden
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12
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Abstract
INTRODUCTION The Fc receptors (FcRs) and their interactions with immunoglobulin and innate immune opsonins, such as C-reactive protein, are key players in humoral and cellular immune responses. As the effector mechanism for some therapeutic monoclonal antibodies, and often a contributor to the pathogenesis and progression of autoimmunity, FcRs are promising targets for treating autoimmune diseases. AREAS COVERED This review discusses the nature of different FcRs and the various mechanisms of their involvement in initiating and modulating immunocyte functions and their biological consequences. It describes a range of current strategies in targeting FcRs and manipulating their interaction with specific ligands, while presenting the pros and cons of these approaches. This review also discusses potential new strategies including regulation of FcR expression and receptor crosstalk. EXPERT OPINION FcRs are appealing targets in the treatment of inflammatory autoimmune diseases. However, there are still knowledge limitations and technical challenges, the most important being a better understanding of the individual roles of each of the FcRs and enhancement of the specificity in targeting particular cell types and specific FcRs.
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Affiliation(s)
- Xinrui Li
- The University of Alabama , SHEL 272, 1825 University Blvd, Birmingham, AL 35294 , USA
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13
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The binding of soluble recombinant human Fcγ receptor I for human immunoglobulin G is conferred by its first and second extracellular domains. Mol Immunol 2013; 54:403-7. [PMID: 23399386 DOI: 10.1016/j.molimm.2013.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Revised: 01/11/2013] [Accepted: 01/11/2013] [Indexed: 11/22/2022]
Abstract
Human FcγRI is a high affinity receptor for the Fc portion of human immunoglobulin G (IgG), and has extracellular, transmembrane and cytoplasmic regions. The extracellular region of human FcγRI, which is the part that interacts with human IgG, is comprised of three immunoglobulin-like domains. Unlike low affinity Fcγ receptors (FcγRII and FcγRIII), FcγRI has a unique third extracellular domain (D3). This study investigated the contribution of D3 to the binding between recombinant human FcγRI (rhFcγRI) and human IgG. The three extracellular domains and the first and second extracellular domains of human FcγRI were expressed by Escherichia coli as rhFcγRI and rhFcγRI-D1D2, respectively. The binding specificity of rhFcγRI-D1D2 to human IgG subclasses was the same as that of rhFcγRI. From surface plasmon resonance analysis, the binding affinity of rhFcγRI-D1D2 for human IgG1/κ was high (the equilibrium dissociation constant: KD=8.04 × 10(-10)M), but slightly lower than that of rhFcγRI (KD=2.59 × 10(-10)M). While the association of rhFcγRI-D1D2 with human IgG1/κ was same as that of rhFcγRI, the dissociation of rhFcγRI-D1D2 was faster than that of rhFcγRI. From these results, D3 of rhFcγRI would not contribute directly to the binding specificity and association of rhFcγRI, but to the holding bound human IgG.
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14
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Asaoka Y, Hatayama K, Tsumoto K, Tomita M, Ide T. Engineering of recombinant human Fcγ receptor I by directed evolution. Protein Eng Des Sel 2012; 25:835-42. [PMID: 22967788 DOI: 10.1093/protein/gzs053] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Human FcγRI is a high-affinity receptor for human IgG. On the basis of its binding activity, recombinant human FcγRI (rhFcγRI) has several possible applications, including as a therapeutic reagent to treat immune complex-mediated disease and as a ligand in affinity chromatography for purification of human IgG. As the stability and production rate of rhFcγRI are low, it would need to be engineered for use in such applications. In this study, we demonstrated engineering of rhFcγRI by directed evolution through random mutagenesis and integration of mutations. Engineered rhFcγRI was expressed by Escherichia coli. Screening identified 19 amino acid mutations contributing to the thermal stability and production rate of rhFcγRI. By integration of these mutations, engineered rhFcγRI containing all 19 amino acid mutations (enFcRd) was constructed and showed markedly enhanced thermal stability (transition midpoint temperature [Tm] = 65.6°C) and production rate (3.27 mg L-medium(-1) OD(600)(-1)) compared with wild-type rhFcγRI (Tm = 48.5°C; production rate, 0.07 mg L-medium(-1) OD(600)(-1)) without a change in the specificities of binding to human IgG subclasses. Moreover, the binding affinity of enFcRd for human IgG1/к (equilibrium dissociation constant [K(D)] = 0.80 × 10(-10) M) was higher than that of wild-type rhFcγRI (K(D) = 1.23 × 10(-10) M). Our study showed that substantial engineering of rhFcγRI is possible.
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Xi J, Zhang GP, Qiao SL, Guo JQ, Wang XN, Yang YY, Zhang LN, Miao XW, Zhao D, Zhi YB, Cai SJ, Luo J, Deng RG. Increased survival and reduced renal injury in MRL/lpr mice treated with a human Fcγ receptor II (CD32) peptide. Immunology 2012; 136:46-53. [PMID: 22236212 DOI: 10.1111/j.1365-2567.2012.03553.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
Systemic lupus erythematosus (SLE) is a multisystem chronic inflammatory disease affecting many organs. The deposition in kidney tissue of immune complexes and their interaction with macrophages is thought to trigger the inflammatory response leading to glomerulonephritis. It has been demonstrated that inhibition of this interaction in murine models can alleviate the disease. Six synthetic peptides were derived from the membrane-proximal extracellular domain (EC2) of human Fcγ receptor II (huFcγRII). Of these, one peptide, huRII6, was shown to be a potent competitive inhibitor of IgG binding to recombinant FcγRII in vitro. To examine the possible therapeutic impact of huRII6 in vivo, this peptide, or a control, was given by subcutaneous injection to female MRL/lpr mice from weeks 7 to 36, resulting in an enhanced survival rate compared with control-treated animals and a reduction of proteinuria. Histopathological examination of the kidneys showed a reduction in deposition of immune complexes and preservation of structure. Such a functional peptide should prove useful for examining the role of IgG-FcγR interactions in experimental models of disease and may provide for the development of FcR-targeting drugs to treat autoimmune disorders.
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Affiliation(s)
- Jun Xi
- School of Food Science and Technology, Henan University of Technology, Zhengzhou, China.
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16
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Fc receptor-targeted therapies for the treatment of inflammation, cancer and beyond. Nat Rev Drug Discov 2012; 11:311-31. [PMID: 22460124 DOI: 10.1038/nrd2909] [Citation(s) in RCA: 256] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The direct or indirect targeting of antibody Fc receptors (FcRs) presents unique opportunities and interesting challenges for the treatment of inflammatory diseases, cancer and infection. Biological responses induced via the Fc portions of antibodies are powerful, complex and unusual, and comprise both activating and inhibitory effects. These properties can be exploited in the engineering of therapeutic monoclonal antibodies to improve their activity in vivo. FcRs have also emerged as key participants in the pathogenesis of several important autoimmune diseases, including systemic lupus erythematosus and rheumatoid arthritis. Therapeutic approaches based on antagonizing FcR function with small molecules or biological drugs such as monoclonal antibodies and recombinant soluble FcR ectodomains have gained momentum. This Review addresses various strategies to manipulate FcR function to overcome immune complex-mediated inflammatory diseases, and considers approaches to improve antibody-based anticancer therapies.
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17
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Efficient expression of recombinant soluble human FcγRI in mammalian cells and its characterization. Protein Expr Purif 2012; 82:155-61. [DOI: 10.1016/j.pep.2011.12.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2011] [Revised: 12/14/2011] [Accepted: 12/20/2011] [Indexed: 11/18/2022]
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18
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Shashidharamurthy R, Machiah D, Bozeman EN, Srivatsan S, Patel J, Cho A, Jacob J, Selvaraj P. Hydrodynamic delivery of plasmid DNA encoding human FcγR-Ig dimers blocks immune-complex mediated inflammation in mice. Gene Ther 2011; 19:877-85. [PMID: 22113315 PMCID: PMC3296821 DOI: 10.1038/gt.2011.175] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Therapeutic use and function of recombinant molecules can be studied by the expression of foreign genes in mice. In this study, we have expressed human Fcgamma receptor –Ig fusion molecules (FcγR-Igs) in mice by administering FcγR-Ig plasmid DNAs hydrodynamically and compared their effectiveness to purified molecules in blocking immune-complex (IC) mediated inflammation in mice. The concentration of hydrodynamically expressed FcγR-Igs (CD16AF-Ig, CD32AR-Ig and CD32AH-Ig) reached a maximum of 130 μg/ml of blood within 24 h after plasmid DNA administration. The in vivo half-life of FcγR-Igs was found to be 9-16 days and Western blot analysis showed that the FcγR-Igs were expressed as a homodimer. The hydrodynamically expressed FcγR-Igs blocked 50-80% of IC-mediated inflammation up to 3 days in a reverse passive Arthus reaction model. Comparative analysis with purified molecules showed that hydrodynamically expressed FcγR-Igs are more efficient than purified molecules in blocking IC-mediated inflammation and had a higher half-life. In summary, these results suggest that the administration of a plasmid vector with a FcγR-Ig gene can be used to study the consequences of blocking IC-binding to FcγRs during the development of inflammatory diseases. This approach may have potential therapeutic value in treating IC-mediated inflammatory autoimmune diseases such as lupus, arthritis and autoimmune vasculitis.
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Affiliation(s)
- R Shashidharamurthy
- Department of Pathology and Laboratory Medicine, Emory University School of Medicine, Atlanta, GA, USA
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19
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Lu J, Ellsworth JL, Hamacher N, Oak SW, Sun PD. Crystal structure of Fcγ receptor I and its implication in high affinity γ-immunoglobulin binding. J Biol Chem 2011; 286:40608-13. [PMID: 21965667 DOI: 10.1074/jbc.m111.257550] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Fcγ receptors (FcγRs) play critical roles in humoral and cellular immune responses through interactions with the Fc region of immunoglobulin G (IgG). Among them, FcγRI is the only high affinity receptor for IgG and thus is a potential target for immunotherapy. Here we report the first crystal structure of an FcγRI with all three extracellular Ig-like domains (designated as D1, D2, and D3). The structure shows that, first, FcγRI has an acute D1-D2 hinge angle similar to that of FcεRI but much smaller than those observed in the low affinity Fcγ receptors. Second, the D3 domain of FcγRI is positioned away from the putative IgG binding site on the receptor and is thus unlikely to make direct contacts with Fc. Third, the replacement of FcγRIII FG-loop ((171)LVGSKNV(177)) with that of FcγRI ((171)MGKHRY(176)) resulted in a 15-fold increase in IgG(1) binding affinity, whereas a valine insertion in the FcγRI FG-loop ((171)MVGKHRY(177)) abolished the affinity enhancement. Thus, the FcγRI FG-loop with its conserved one-residue deletion is critical to the high affinity IgG binding. The structural results support FcγRI binding to IgG in a similar mode as its low affinity counterparts. Taken together, our study suggests a molecular mechanism for the high affinity IgG recognition by FcγRI and provides a structural basis for understanding its physiological function and its therapeutic implication in treating autoimmune diseases.
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Affiliation(s)
- Jinghua Lu
- Structural Immunology Section, Laboratory of Immunogenetics, NIAID, National Institutes of Health, Rockville, Maryland, USA
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20
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Administering human adipose-derived mesenchymal stem cells to prevent and treat experimental arthritis. Clin Immunol 2011; 141:328-37. [PMID: 21944669 DOI: 10.1016/j.clim.2011.08.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2011] [Revised: 08/25/2011] [Accepted: 08/26/2011] [Indexed: 02/08/2023]
Abstract
Rheumatoid arthritis is a chronic autoimmune disease and affecting approximately 1% of the population. Human adipose-derived mesenchymal stem cells (hASCs) were recently found to suppress effector T cell and inflammatory responses and, thus, to have beneficial effects in various autoimmune diseases. In this study, we examined whether hASCs could play a protective and/or therapeutic role in collagen-induced arthritis (CIA). We showed that hASCs both prevented and treated CIA by significantly reducing the incidence and severity of experimental arthritis. We further demonstrated that treatment with hASCs inhibited the production of various inflammatory mediators, decreased antigen-specific Th1/Th17 cell expansion, and induced the production of anti-inflammatory cytokine interleukin-10. Moreover, hASCs could induce the generation of antigen-specific Treg cells with the capacity to suppress collagen-specific T cell responses.
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21
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Levin SD, Taft DW, Brandt CS, Bucher C, Howard ED, Chadwick EM, Johnston J, Hammond A, Bontadelli K, Ardourel D, Hebb L, Wolf A, Bukowski TR, Rixon MW, Kuijper JL, Ostrander CD, West JW, Bilsborough J, Fox B, Gao Z, Xu W, Ramsdell F, Blazar BR, Lewis KE. Vstm3 is a member of the CD28 family and an important modulator of T-cell function. Eur J Immunol 2011; 41:902-15. [PMID: 21416464 DOI: 10.1002/eji.201041136] [Citation(s) in RCA: 248] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2010] [Revised: 11/16/2010] [Accepted: 01/07/2011] [Indexed: 12/13/2022]
Abstract
Members of the CD28 family play important roles in regulating T-cell functions and share a common gene structure profile. We have identified VSTM3 as a protein whose gene structure matches that of the other CD28 family members. This protein (also known as TIGIT and WUCAM) has been previously shown to affect immune responses and is expressed on NK cells, activated and memory T cells, and Tregs. The nectin-family proteins CD155 and CD112 serve as counter-structures for VSTM3, and CD155 and CD112 also bind to the activating receptor CD226 on T cells and NK cells. Hence, this group of interacting proteins forms a network of molecules similar to the well-characterized CD28-CTLA-4-CD80-CD86 network. In the same way that soluble CTLA-4 can be used to block T-cell responses, we show that soluble Vstm3 attenuates T-cell responses in vitro and in vivo. Moreover, animals deficient in Vstm3 are more sensitive to autoimmune challenges indicating that this new member of the CD28 family is an important regulator of T-cell responses.
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Affiliation(s)
- Steven D Levin
- Department of Immunology, ZymoGenetics, Inc., Seattle, WA, USA.
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22
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Jung ST, Kang TH, Georgiou G. Efficient expression and purification of human aglycosylated Fcgamma receptors in Escherichia coli. Biotechnol Bioeng 2010; 107:21-30. [PMID: 20506277 DOI: 10.1002/bit.22785] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Effector Fc gamma receptors (FcgammaRs) are expressed on the surface of a variety of cells of hematopoietic lineage and serve as a bridge between adaptive and innate immune responses. The interaction between immune complexes, formed by IgG class antibodies that are crosslinked with antigen, and FcgammaRs triggers signaling cascades that result in numerous cellular responses including the activation or donwregulation of cytotoxic responses, cytokine release, and antibody synthesis. Here, the extracellular domains of the human type I transmembrane FcgammaRs were expressed in Escherichia coli and their interactions to subclass IgGs (IgG1, IgG2, IgG3, and IgG4) antibodies were analyzed. Expression using fully synthetic E. coli codon optimized FcgammaR genes and optimization of sequences for N-terminal translation initiation region through mRNA secondary structure prediction enabled us to achieve high yield of purified, bacterially expressed receptors, including FcgammaRI and FcgammaRIIIa which have not been successfully expressed in bacteria until now. The aglycosylated FcgammaRs showed similar IgG subclass binding selectivity compared to the respective glycosylated FcgammaRs expressed in mammalian cells.
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Affiliation(s)
- Sang Taek Jung
- Department of Chemical Engineering, University of Texas, Austin, 78712, USA
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Ellsworth JL, Hamacher N, Harder B, Maurer M, Bukowski TR, Lantry M, Noriega C, Rixon MW, Fox B, Lewis K, Meengs B, Rollins E, Greeff K, Meyer J, Birks C. Generation of a high-affinity Fcgamma receptor by Ig-domain swapping between human CD64A and CD16A. Protein Eng Des Sel 2010; 23:299-309. [PMID: 20150179 DOI: 10.1093/protein/gzq007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A recombinant soluble version of the human high-affinity receptor for IgG, rh-FcgammaRIA or CD64A, was expressed in mammalian cells and purified from their conditioned media. As assessed by circular dichroism, size exclusion chromatography and dynamic light scattering, incubation of rh-FcgammaRIA at 37 degrees C resulted in time-dependent formation of soluble aggregates caused by protein unfolding and loss of native structure. Aggregate formation was irreversible, temperature-dependent and was independent of rh-FcgammaRIA concentration. Aggregated rh-FcgammaRIA lost its ability to inhibit immune complex precipitation and failed to bind to IgG-Sepharose. Addition of human IgG1 to rh-FcgammaRIA prior to incubation at 37 degrees C blocked the formation of rh-FcgammaRIA aggregates. Production of soluble monomeric rh-FcgammaRIA was limited by aggregate formation during cell culture. Substitution of the membrane distal D1 Ig domain of FcgammaRIA with the D1 Ig domain of FcgammaRIIIA or CD16A resulted in a chimeric receptor, FcgammaR3A1A, with enhanced temperature stability. Relative to native rh-FcgammaRIA, FcgammaR3A1A exhibited less aggregation in Chinese hamster ovary cell-conditioned media or when purified receptor was incubated for up to 24 h at 37 degrees C. Both receptors bound to immobilized human IgG1 with high affinity and were equipotent at blockade of immune complex-mediated cytokine production from cultured mast cells. Equivalent dose-dependent reductions in edema and neutrophil infiltration in the cutaneous Arthus reaction in mice were noted for rh-FcgammaRIA and FcgammaR3A1A. These data demonstrate that the D1 Ig domains of FcgammaRIA and FcgammaRIIIA are functionally interchangeable and further suggest that the chimeric receptor FcgammaR3A1A is an effective inhibitor of type III hypersensitivity in mice.
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Affiliation(s)
- Jeff L Ellsworth
- Department of Immunology, ZymoGenetics, Inc., Seattle, WA 98102, USA.
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