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Fitzpatrick EA, Wang J, Strome SE. Engineering of Fc Multimers as a Protein Therapy for Autoimmune Disease. Front Immunol 2020; 11:496. [PMID: 32269572 PMCID: PMC7109252 DOI: 10.3389/fimmu.2020.00496] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2019] [Accepted: 03/04/2020] [Indexed: 02/06/2023] Open
Abstract
The success of Intravenous Immunoglobulin in treating autoimmune and inflammatory processes such as immune thrombocytopenia purpura and Kawasaki disease has led to renewed interest in developing recombinant molecules capable of recapitulating these therapeutic effects. The anti-inflammatory properties of IVIG are, in part, due to the Fc region of the IgG molecule, which interacts with activating or inhibitory Fcγ receptors (FcγRs), the neonatal Fc Receptor, non-canonical FcRs expressed by immune cells and complement proteins. In most cases, Fc interactions with these cognate receptors are dependent upon avidity—avidity which naturally occurs when polyclonal antibodies recognize unique antigens on a given target. The functional consequences of these avid interactions include antibody dependent cell-mediated cytotoxicity, antibody dependent cell phagocytosis, degranulation, direct killing, and/or complement activation—all of which are associated with long-term immunomodulatory effects. Many of these immunologic effects can be recapitulated using recombinant or non-recombinant approaches to induce Fc multimerization, affording the potential to develop a new class of therapeutics. In this review, we discuss the history of tolerance induction by immune complexes that has led to the therapeutic development of artificial Fc bearing immune aggregates and recombinant Fc multimers. The contribution of structure, aggregation and N-glycosylation to human IgG: FcγR interactions and the functional effect(s) of these interactions are reviewed. Understanding the mechanisms by which Fc multimers induce tolerance and attempts to engineer Fc multimers to target specific FcγRs and/or specific effector functions in autoimmune disorders is explored in detail.
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Affiliation(s)
- Elizabeth A Fitzpatrick
- Department of Microbiology, Immunology and Biochemistry, College of Medicine, University of Tennessee Health Science Center (UTHSC), Memphis, TN, United States
| | - Jin Wang
- College of Graduate Health Sciences, University of Tennessee Health Science Center, Memphis, TN, United States
| | - S E Strome
- Department of Microbiology, Immunology and Biochemistry, College of Medicine, University of Tennessee Health Science Center (UTHSC), Memphis, TN, United States
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Kim JH, Ye YM, Ban GY, Shin YS, Lee HY, Nam YH, Lee SK, Cho YS, Jang SH, Jung KS, Park HS. Effects of Immunoglobulin Replacement on Asthma Exacerbation in Adult Asthmatics with IgG Subclass Deficiency. ALLERGY, ASTHMA & IMMUNOLOGY RESEARCH 2017; 9:526-533. [PMID: 28913992 PMCID: PMC5603481 DOI: 10.4168/aair.2017.9.6.526] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2017] [Revised: 06/02/2017] [Accepted: 06/13/2017] [Indexed: 12/29/2022]
Abstract
Purpose Recurrent respiratory tract infection is a common manifestation of primary immunodeficiency disease, and respiratory viruses or bacteria are important triggers of asthma exacerbations. Asthma often coexists with humoral immunodeficiency in adults, and some asthmatics with immunoglobulin (Ig) G subclass deficiency (IgGSCD) suffer from recurrent exacerbations. Although some studies suggest a benefit from Ig replacement, others have failed to support its use. This study aimed to assess the effect of Ig replacement on asthma exacerbation caused by respiratory infection as well as the asthma control status of adult asthmatics with IgGSCD. Methods This is a multi-center, open-label study of adult asthmatics with IgGSCD. All patients received monthly intravenous immunoglobulin (IVIG) for 6 months and were evaluated regarding asthma exacerbation related to infection, asthma control status, quality of life, and lung function before and after IVIG infusion. Results A total of 30 patients were enrolled, and 24 completed the study. Most of the patients had a moderate degree of asthma severity with partly (52%) or uncontrolled (41%) status at baseline. IVIG significantly reduced the proportion of patients with asthma exacerbations, lowered the number of respiratory infections, and improved asthma control status, compared to the baseline values (P<0.001). The mean asthma-specific quality of life and asthma control test scores were improved significantly (P=0.009 and P=0.053, respectively); however, there were no significant changes in lung function. Conclusions IVIG reduced the frequency of asthma exacerbations and improved asthma control status in adult asthmatics with IgGSCD, suggesting that IVIG could be an effective treatment option in this population.
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Affiliation(s)
- Joo Hee Kim
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea
| | - Young Min Ye
- Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea
| | - Ga Young Ban
- Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea
| | - Yoo Seob Shin
- Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea
| | - Hyun Young Lee
- Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea
| | - Young Hee Nam
- Department of Allergy and Clinical Immunology, Dong-A University College of Medicine, Busan, Korea
| | - Soo Keol Lee
- Department of Allergy and Clinical Immunology, Dong-A University College of Medicine, Busan, Korea
| | - You Sook Cho
- Department of Allergy and Clinical Immunology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea
| | - Seung Hun Jang
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea
| | - Ki Suck Jung
- Division of Pulmonary, Allergy, and Critical Care Medicine, Department of Medicine, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea
| | - Hae Sim Park
- Department of Allergy and Clinical Immunology, Ajou University School of Medicine, Suwon, Korea.
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Kaufman GN, Massoud AH, Dembele M, Yona M, Piccirillo CA, Mazer BD. Induction of Regulatory T Cells by Intravenous Immunoglobulin: A Bridge between Adaptive and Innate Immunity. Front Immunol 2015; 6:469. [PMID: 26441974 PMCID: PMC4566032 DOI: 10.3389/fimmu.2015.00469] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Accepted: 08/28/2015] [Indexed: 12/25/2022] Open
Abstract
Intravenous immunoglobulin (IVIg) is a polyclonal immunoglobulin G preparation with potent immunomodulatory properties. The mode of action of IVIg has been investigated in multiple disease states, with various mechanisms described to account for its benefits. Recent data indicate that IVIg increases both the number and the suppressive capacity of regulatory T cells, a subpopulation of T cells that are essential for immune homeostasis. IVIg alters dendritic cell function, cytokine and chemokine networks, and T lymphocytes, leading to development of regulatory T cells. The ability of IVIg to influence Treg induction has been shown both in animal models and in human diseases. In this review, we discuss data on the potential mechanisms contributing to the interaction between IVIg and the regulatory T-cell compartment.
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Affiliation(s)
- Gabriel N Kaufman
- Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada
| | - Amir H Massoud
- Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada ; Laboratory of Cellular and Molecular Immunology, University of Montreal Hospital Research Centre , Montreal, QC , Canada
| | - Marieme Dembele
- Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada
| | - Madelaine Yona
- Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada
| | - Ciriaco A Piccirillo
- Infectious Diseases and Immunity in Global Health Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada
| | - Bruce D Mazer
- Translational Research in Respiratory Diseases Program, The Research Institute of the McGill University Health Centre , Montreal, QC , Canada ; Department of Pediatrics, Faculty of Medicine, McGill University , Montreal, QC , Canada
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Nakada T. Effects of anti-inflammatory drugs on intravenous immunoglobulin therapy in the acute phase of Kawasaki disease. Pediatr Cardiol 2015; 36:335-9. [PMID: 25158631 DOI: 10.1007/s00246-014-1010-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Accepted: 08/20/2014] [Indexed: 12/18/2022]
Abstract
This retrospective study aimed to investigate the effects of anti-inflammatory drugs (ADs) on intravenous immunoglobulin (IVIG) therapy in the acute phase of Kawasaki disease. In total, 182 pediatric patients who received IVIG therapy for Kawasaki disease between 1999 and 2013 at the Department of Pediatrics, Aomori Prefectural Central Hospital were enrolled. Patients were divided into 2 groups: an S group, including 111 patients who received single IVIG therapy with delayed administration of ADs, and a T group, including 71 patients who received concomitant AIDs with IVIG. During the study, the only ADs administered were aspirin (A: 30 mg/kg/day) or flurbiprofen (F: 3-5 mg/kg/day). Steroids were not administered to any patient. The regimen of the S group was partially used after 2004 and was used to all patients after 2009. The following clinical findings were significantly different between the S and T groups: disease onset before 2003 (0 vs. 59%, P < 0.001) and after 2009 (70 vs. 0%, P < 0.001), use of 2-g/kg/day IVIG therapy (100 vs. 93%, P = 0.034), ADs type (A/F: 62/49 vs. 17/54, P < 0.001), and the prevalence of coronary artery lesions (CAL) up to (1/111 vs. 11/71, P < 0.001) and after 30 days of illness (0/111 vs. 4/71, P = 0.022). Logistic regression analysis revealed that IVIG therapy only (S group; P = 0.009) and 2-g/kg/day IVIG therapy (P = 0.015) were significant factors for CAL suppression. The findings revealed a possible negative impact of ADs on initial IVIG therapy in the acute phase of Kawasaki disease. Initial single IVIG therapy with delayed administration of ADs may be useful to suppress CAL caused by Kawasaki disease.
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Affiliation(s)
- Toshimasa Nakada
- Department of Pediatrics, Aomori Prefectural Central Hospital, Higashi-Tukurimiti 2-1-1, Aomori City, Aomori Prefecture, 030-8553, Japan,
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Phospholipase cε, an effector of ras and rap small GTPases, is required for airway inflammatory response in a mouse model of bronchial asthma. PLoS One 2014; 9:e108373. [PMID: 25269075 PMCID: PMC4182471 DOI: 10.1371/journal.pone.0108373] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2014] [Accepted: 08/20/2014] [Indexed: 11/29/2022] Open
Abstract
Background Phospholipase Cε (PLCε) is an effector of Ras and Rap small GTPases and expressed in non-immune cells. It is well established that PLCε plays an important role in skin inflammation, such as that elicited by phorbol ester painting or ultraviolet irradiation and contact dermatitis that is mediated by T helper (Th) 1 cells, through upregulating inflammatory cytokine production by keratinocytes and dermal fibroblasts. However, little is known about whether PLCε is involved in regulation of inflammation in the respiratory system, such as Th2-cells-mediated allergic asthma. Methods We prepared a mouse model of allergic asthma using PLCε+/+ mice and PLCεΔX/ΔX mutant mice in which PLCε was catalytically-inactive. Mice with different PLCε genotypes were immunized with ovalbumin (OVA) followed by the challenge with an OVA-containing aerosol to induce asthmatic response, which was assessed by analyzing airway hyper-responsiveness, bronchoalveolar lavage fluids, inflammatory cytokine levels, and OVA-specific immunoglobulin (Ig) levels. Effects of PLCε genotype on cytokine production were also examined with primary-cultured bronchial epithelial cells. Results After OVA challenge, the OVA-immunized PLCεΔX/ΔX mice exhibited substantially attenuated airway hyper-responsiveness and broncial inflammation, which were accompanied by reduced Th2 cytokine content in the bronchoalveolar lavage fluids. In contrast, the serum levels of OVA-specific IgGs and IgE were not affected by the PLCε genotype, suggesting that sensitization was PLCε-independent. In the challenged mice, PLCε deficiency reduced proinflammatory cytokine production in the bronchial epithelial cells. Primary-cultured bronchial epithelial cells prepared from PLCεΔX/ΔX mice showed attenuated pro-inflammatory cytokine production when stimulated with tumor necrosis factor-α, suggesting that reduced cytokine production in PLCεΔX/ΔX mice was due to cell-autonomous effect of PLCε deficiency. Conclusions PLCε plays an important role in the pathogenesis of bronchial asthma through upregulating inflammatory cytokine production by the bronchial epithelial cells.
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Othy S, Bruneval P, Topçu S, Dugail I, Delers F, Lacroix-Desmazes S, Bayry J, Kaveri SV. Effect of IVIg on human dendritic cell-mediated antigen uptake and presentation: Role of lipid accumulation. J Autoimmun 2012; 39:168-72. [DOI: 10.1016/j.jaut.2012.05.013] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Accepted: 05/20/2012] [Indexed: 11/25/2022]
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Lopez-Parra V, Mallavia B, Lopez-Franco O, Ortiz-Muñoz G, Oguiza A, Recio C, Blanco J, Nimmerjahn F, Egido J, Gomez-Guerrero C. Fcγ receptor deficiency attenuates diabetic nephropathy. J Am Soc Nephrol 2012; 23:1518-27. [PMID: 22859852 DOI: 10.1681/asn.2011080822] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Among patients with diabetes, increased production of immunoglobulins against proteins modified by diabetes is associated with proteinuria and cardiovascular risk, suggesting that immune mechanisms may contribute to the development of diabetes complications, such as nephropathy. We investigated the contribution of IgG Fcγ receptors to diabetic renal injury in hyperglycemic, hypercholesterolemic mice. We used streptozotocin to induce diabetes in apolipoprotein E-deficient mice and in mice deficient in both apolipoprotein E and γ-chain, the common subunit of activating Fcγ receptors. After 15 weeks, the mice lacking Fcγ receptors had significantly less albuminuria and renal hypertrophy, despite similar degrees of hyperglycemia and hypercholesterolemia, immunoglobulin production, and glomerular immune deposits. Moreover, diabetic Fcγ receptor-deficient mice had less mesangial matrix expansion, inflammatory cell infiltration, and collagen and α-smooth muscle actin content in their kidneys. Accordingly, expression of genes involved in leukocyte infiltration, fibrosis, and oxidative stress was significantly reduced in diabetic kidneys and in mesangial cells cultured from Fcγ receptor-deficient mice. In summary, preventing the activation of Fcγ receptors alleviates renal hypertrophy, inflammation, and fibrosis in hypercholesterolemic mice with diabetes, suggesting that modulating Fcγ receptor signaling may be renoprotective in diabetic nephropathy.
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Affiliation(s)
- Virginia Lopez-Parra
- Renal and Vascular Inflammation Laboratory, IIS-Fundacion Jimenez Diaz, Autonoma University, Avda Reyes Catolicos, 2 28040 Madrid, Spain
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Batard T, Zimmer A, Nony E, Bouley J, Airouche S, Luce S, Turfkruyer M, Tourdot S, Mascarell L, Moingeon P. Anti-inflammatory activity of sublingual immunoglobulin (SLIG) in a murine model of allergen-driven airway inflammation. Vaccine 2012; 30:5666-74. [PMID: 22776213 DOI: 10.1016/j.vaccine.2012.06.049] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Revised: 05/31/2012] [Accepted: 06/16/2012] [Indexed: 01/27/2023]
Abstract
AIM Intravenous immunoglobulin (IVIG) displays anti-inflammatory activities in many diseases. Subcutaneous administration of anti-IgE in humans provides benefit in severe persistent allergic asthma. Given the well established efficacy of sublingual allergen immunotherapy in respiratory type I allergies, we investigated the therapeutic potential of sublingual immunoglobulin (SLIG), most particularly anti-IgE SLIG, in a murine model of allergen-driven airway inflammation. METHODS BALB/c mice sensitized with ovalbumin (OVA) were treated sublingually with rat monoclonal IgG1 or IgG2a, either directed to mouse IgE or with no reported specificity. Airway hyperresponsiveness (AHR) was assessed by whole body plethysmography, and eosinophil infiltrates were characterized in bronchial alveolar lavages (BAL). OVA-specific antibody and T cell responses were analyzed in sera and saliva or lung and draining lymph nodes, by ELISA or CBA measurement of cytokine production, respectively. RESULTS AHR and BAL eosinophil infiltrates were substantially decreased in mice treated sublingually with particulate OVA (positive control), as well as in animals receiving various rat IgG1, irrespective of their specificity for murine IgE. In contrast, no improvement was observed in mice treated with PBS (negative control) or various rat IgG2a. SLIG anti-inflammatory activity is not related to a downregulation of Th2, Th17 or an induction of Foxp3(+) CD4(+) regulatory T cell responses. Mass spectrometry analysis of glycan moieties, such as sialic acid, suggests that the differential efficacy of rat IgG1 and IgG2a is not related to their capacity to interact with lectins borne by oral immune cells. CONCLUSIONS In a murine model of allergen-driven airway inflammation, SLIG exhibits an anti-inflammatory activity irrespective of the immunoglobulin specificity, and in the absence of allergen. As a noninvasive approach, SLIG deserves to be further studied as a treatment for other inflammatory diseases beyond allergic asthma.
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Affiliation(s)
- T Batard
- Stallergenes, 6 rue Alexis de Tocqueville, 92160 Antony, France.
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Massoud AH, Guay J, Shalaby KH, Bjur E, Ablona A, Chan D, Nouhi Y, McCusker CT, Mourad MW, Piccirillo CA, Mazer BD. Intravenous immunoglobulin attenuates airway inflammation through induction of forkhead box protein 3-positive regulatory T cells. J Allergy Clin Immunol 2012; 129:1656-65.e3. [PMID: 22564681 DOI: 10.1016/j.jaci.2012.02.050] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2011] [Revised: 01/27/2012] [Accepted: 02/28/2012] [Indexed: 11/25/2022]
Abstract
BACKGROUND Intravenous immunoglobulin (IVIG) is a frequently used disease-modifying therapy for a large spectrum of autoimmune and inflammatory conditions, yet its mechanisms of action are incompletely understood. Using a robust murine model of antigen-driven allergic airways disease, we have demonstrated that IVIG markedly improves ovalbumin (OVA)-induced airway hyperresponsiveness characterized by 4- to 6-fold enhancement in regulatory T (Treg) cells in pulmonary and associated lymphoid tissues. OBJECTIVE We sought to determine whether IVIG induces antigen-specific Treg cells and to address cellular interactions that lead to induction of Treg cells by IVIG. METHODS C57Bl/6 mice were sensitized and challenged by means of intranasal OVA exposure. IVIG or albumin control was administered 24 hours before challenge. Treg cells were tracked by using green fluorescent protein (GFP)-forkhead box protein 3 (Foxp3) knock-in reporter mice (Foxp3(GFP)), and Treg cell and dendritic cell (DC) phenotypes and activities were elucidated by using coculture and flow cytometry. RESULTS IVIG therapy of OVA-sensitized and OVA-challenged mice induced antigen-specific forkhead box protein 3 (Foxp3)-positive Treg cells from non-Treg cell precursors. The induced Treg cells home specifically to the lungs and draining lymph nodes and have greatly potentiated suppressive activity compared with that seen in Treg cells purified from control mice. Induction of Treg cells is mediated by tolerogenic DCs generated after IVIG exposure. Compared with albumin-treated, OVA-exposed mice, IVIG-primed DCs express altered Notch ligands, including increased Delta-4 and reduced Jagged-1 levels, reflecting decreased T(H)2 polarization. Furthermore, IVIG-primed DCs can stimulate Treg cell differentiation from uncommitted Foxp3(-)CD4(+) T cells ex vivo, and adoptive transfer of IVIG-primed DCs abrogates airway hyperresponsiveness and induces Treg cells. CONCLUSION The anti-inflammatory effects of IVIG therapy can be mediated by the immunomodulation of DCs, creating a bridge that induces antigen-specific, highly suppressive Treg cells.
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Affiliation(s)
- Amir H Massoud
- Meakins Christie Laboratories, McGill University Health Center-Research Institute, Montreal, Quebec, Canada
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Ishikawa Y, Kobayashi K, Yamamoto M, Nakata K, Takagawa T, Funada Y, Kotani Y, Karasuyama H, Yoshida M, Nishimura Y. Antigen-Specific IgG ameliorates allergic airway inflammation via Fcγ receptor IIB on dendritic cells. Respir Res 2011; 12:42. [PMID: 21477339 PMCID: PMC3079623 DOI: 10.1186/1465-9921-12-42] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2010] [Accepted: 04/10/2011] [Indexed: 12/12/2022] Open
Abstract
Background There have been few reports on the role of Fc receptors (FcRs) and immunoglobulin G (IgG) in asthma. The purpose of this study is to clarify the role of inhibitory FcRs and antigen presenting cells (APCs) in pathogenesis of asthma and to evaluate antigen-transporting and presenting capacity by APCs in the tracheobronchial mucosa. Methods In FcγRIIB deficient (KO) and C57BL/6 (WT) mice, the effects of intratracheal instillation of antigen-specific IgG were analysed using the model with sensitization and airborne challenge with ovalbumin (OVA). Thoracic lymph nodes instilled with fluorescein-conjugated OVA were analysed by fluorescence microscopy. Moreover, we analysed the CD11c+ MHC class II+ cells which intaken fluorescein-conjugated OVA in thoracic lymph nodes by flow cytometry. Also, lung-derived CD11c+ APCs were analysed by flow cytometry. Effects of anti-OVA IgG1 on bone marrow dendritic cells (BMDCs) in vitro were also analysed. Moreover, in FcγRIIB KO mice intravenously transplanted dendritic cells (DCs) differentiated from BMDCs of WT mice, the effects of intratracheal instillation of anti-OVA IgG were evaluated by bronchoalveolar lavage (BAL). Results In WT mice, total cells and eosinophils in BAL fluid reduced after instillation with anti-OVA IgG1. Anti-OVA IgG1 suppressed airway inflammation in hyperresponsiveness and histology. In addition, the number of the fluorescein-conjugated OVA in CD11c+ MHC class II+ cells of thoracic lymph nodes with anti-OVA IgG1 instillation decreased compared with PBS. Also, MHC class II expression on lung-derived CD11c+ APCs with anti-OVA IgG1 instillation reduced. Moreover, in vitro, we showed that BMDCs with anti-OVA IgG1 significantly decreased the T cell proliferation. Finally, we demonstrated that the lacking effects of anti-OVA IgG1 on airway inflammation on FcγRIIB KO mice were restored with WT-derived BMDCs transplanted intravenously. Conclusion Antigen-specific IgG ameliorates allergic airway inflammation via FcγRIIB on DCs.
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Affiliation(s)
- Yumiko Ishikawa
- Division of Respiratory Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, Kobe, Japan
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