1
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Raposo-Gutiérrez I, Rodríguez-Ronchel A, Ramiro AR. Atherosclerosis antigens as targets for immunotherapy. NATURE CARDIOVASCULAR RESEARCH 2023; 2:1129-1147. [PMID: 39196152 DOI: 10.1038/s44161-023-00376-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 10/18/2023] [Indexed: 08/29/2024]
Abstract
Atherosclerosis is a chronic inflammatory disease of the arteries that can lead to thrombosis, infarction and stroke, underlying the first cause of mortality worldwide. Adaptive immunity plays critical roles in atherosclerosis, and numerous studies have ascribed both atheroprotective and atherogenic functions to specific subsets of T and B cells. However, less is known on how antigen specificity determines the protective or adverse outcome of such adaptive responses. Understanding antigen triggers in atherosclerosis is crucial to delve deeper into mechanisms of disease initiation and progression and to implement specific immunotherapeutic approaches, including vaccination strategies. Here we review the role of adaptive immunity in atherosclerosis and the insights that single-cell technology has provided into the function of distinct immune cell subsets. We outline the most relevant atherosclerosis antigens and antibodies reported to date and examine their immunotherapeutic potential. Finally, we review the most promising vaccination-based clinical trials targeting the adaptive immune system.
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Affiliation(s)
- Irene Raposo-Gutiérrez
- B Lymphocyte Lab, Novel Mechanisms of Atherosclerosis Program, Spanish National Center for Cardiovascular Research, Madrid, Spain
| | - Ana Rodríguez-Ronchel
- B Lymphocyte Lab, Novel Mechanisms of Atherosclerosis Program, Spanish National Center for Cardiovascular Research, Madrid, Spain
| | - Almudena R Ramiro
- B Lymphocyte Lab, Novel Mechanisms of Atherosclerosis Program, Spanish National Center for Cardiovascular Research, Madrid, Spain.
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2
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López-Sanz L, Bernal S, Jiménez-Castilla L, Pardines M, Hernández-García A, Blanco-Colio L, Martín-Ventura JL, Gómez Guerrero C. The presence of activating IgG Fc receptors in macrophages aggravates the development of experimental abdominal aortic aneurysm. CLINICA E INVESTIGACION EN ARTERIOSCLEROSIS : PUBLICACION OFICIAL DE LA SOCIEDAD ESPANOLA DE ARTERIOSCLEROSIS 2023; 35:185-194. [PMID: 36737385 DOI: 10.1016/j.arteri.2022.12.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 12/16/2022] [Accepted: 12/22/2022] [Indexed: 02/04/2023]
Abstract
INTRODUCTION Abdominal aortic aneurysm (AAA) is a multifactorial, degenerative disease characterized by progressive aortic dilation and chronic activation of inflammation, proteolytic activity, and oxidative stress in the aortic wall. The immune response triggered by antibodies against antigens present in the vascular wall participates in the formation and progression of AAA through mechanisms not completely understood. This work analyses the function of specific IgG receptors (FcγR), especially those expressed by monocytes/macrophages, in the development of experimental AAA. METHODS In the elastase-induced AAA model, the abdominal aortas from wildtype and FcγR deficient mice with/without macrophage adoptive transfer were analysed by histology and quantitative PCR. In vitro, mouse macrophages were transfected with RNA interference of FcγRIV/CD16.2 or treated with Syk kinase inhibitor before stimulation with IgG immune complexes. RESULTS Macrophage adoptive transfer in FcγR deficient mice increased the susceptibility to AAA development. Mice receiving macrophages with functional FcγR exhibited higher aortic diameter increase, higher content of macrophages and B lymphocytes, and upregulated expression of chemokine CCL2, cytokines (TNF-α and IL-17), metalloproteinase MMP2, prooxidant enzyme NADPH oxidase-2, and the isoforms FcγRIII/CD16 and FcγRIV/CD16.2. In vitro, both FcγRIV/CD16.2 gene silencing and Syk inhibition reduced cytokines and reactive oxygen species production induced by immune complexes in macrophages. CONCLUSIONS Activation of macrophage FcγR contributes to AAA development by inducing mediators of inflammation, proteolysis, and oxidative stress. Modulation of FcγR or effector molecules may represent a potential target for AAA treatment.
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Affiliation(s)
- Laura López-Sanz
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), Madrid, España
| | - Susana Bernal
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), Madrid, España
| | - Luna Jiménez-Castilla
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), Madrid, España
| | - Marisa Pardines
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España
| | - Ana Hernández-García
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España
| | - Luis Blanco-Colio
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, España
| | - José Luis Martín-Ventura
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Enfermedades Cardiovasculares (CIBERCV), Madrid, España
| | - Carmen Gómez Guerrero
- Laboratorio de Patología Vascular y Renal, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz, Universidad Autónoma de Madrid (IIS-FJD/UAM), Madrid, España; Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas (CIBERDEM), Madrid, España.
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3
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Rowaiye AB, Asala T, Oli AN, Uzochukwu IC, Akpa A, Esimone CO. The Activating Receptors of Natural Killer Cells and Their Inter-Switching Potentials. Curr Drug Targets 2021; 21:1733-1751. [PMID: 32914713 DOI: 10.2174/1389450121666200910160929] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 07/14/2020] [Accepted: 07/24/2020] [Indexed: 12/18/2022]
Abstract
The global incidence of cancer is on the increase and researchers are prospecting for specific and non-selective therapies derived from the immune system. The killer activating receptors of NK cells are known to be involved in immunosurveillance against tumor and virally-infected cells. These receptors belong to two main categories, namely the immunoglobulin like and C-lectin like families. Though they have different signal pathways, all the killer activating receptors have similar effector functions which include direct cytotoxicity and the release of inflammatory cytokines such as IFN-gamma and TNF-alpha. To transduce signals that exceed the activation threshold for cytotoxicity, most of these receptors require synergistic effort. This review profiles 21 receptors: 13 immunoglobulin-like, 5 lectin-like, and 3 others. It critically explores their structural uniqueness, role in disease, respective transduction signal pathways and their status as current and prospective targets for cancer immunotherapy. While the native ligands of most of these receptors are known, much work is required to prospect for specific antibodies, peptides and multi-target small molecules with high binding affinities.
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Affiliation(s)
| | - Titilayo Asala
- Department of Medical Biotechnology, National Biotechnology Development Agency, Abuja, Nigeria
| | - Angus Nnamdi Oli
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Agulu, Anambra state, Nigeria
| | - Ikemefuna Chijioke Uzochukwu
- Department of Pharmaceutical and Medicinal Chemistry, Faculty of Pharmaceutical sciences, Nnamdi Azikiwe University, Agulu, Anambra state, Nigeria
| | - Alex Akpa
- Department of Medical Biotechnology, National Biotechnology Development Agency, Abuja, Nigeria
| | - Charles Okechukwu Esimone
- Department of Pharmaceutical Microbiology and Biotechnology, Faculty of Pharmaceutical Sciences, Nnamdi Azikiwe University, Agulu, Anambra state, Nigeria
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4
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Johnson AA, Shokhirev MN. Pan-Tissue Aging Clock Genes That Have Intimate Connections with the Immune System and Age-Related Disease. Rejuvenation Res 2021; 24:377-389. [PMID: 34486398 DOI: 10.1089/rej.2021.0012] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
In our recent transcriptomic meta-analysis, we used random forest machine learning to accurately predict age in human blood, bone, brain, heart, and retina tissues given gene inputs. Although each tissue-specific model utilized a unique number of genes for age prediction, we found that the following six genes were prioritized in all five tissues: CHI3L2, CIDEC, FCGR3A, RPS4Y1, SLC11A1, and VTCN1. Since being selected for age prediction in multiple tissues is unique, we decided to explore these pan-tissue clock genes in greater detail. In the present study, we began by performing over-representation and network topology-based enrichment analyses in the Gene Ontology Biological Process database. These analyses revealed that the immunological terms "response to protozoan," "immune response," and "positive regulation of immune system process" were significantly enriched by these clock inputs. Expression analyses in mouse and human tissues identified that these inputs are frequently upregulated or downregulated with age. A detailed literature search showed that all six genes had noteworthy connections to age-related disease. For example, mice deficient in Cidec are protected against various metabolic defects, while suppressing VTCN1 inhibits age-related cancers in mouse models. Using a large multitissue transcriptomic dataset, we additionally generate a novel, minimalistic aging clock that can predict human age using just these six genes as inputs. Taken all together, these six genes are connected to diverse aspects of aging.
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Affiliation(s)
| | - Maxim N Shokhirev
- Razavi Newman Integrative Genomics and Bioinformatics Core, Salk Institute for Biological Studies, La Jolla, California, USA
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5
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Porsch F, Mallat Z, Binder CJ. Humoral immunity in atherosclerosis and myocardial infarction: from B cells to antibodies. Cardiovasc Res 2021; 117:2544-2562. [PMID: 34450620 DOI: 10.1093/cvr/cvab285] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 07/30/2021] [Accepted: 08/24/2021] [Indexed: 02/06/2023] Open
Abstract
Immune mechanisms are critically involved in the pathogenesis of atherosclerosis and its clinical manifestations. Associations of specific antibody levels and defined B cell subsets with cardiovascular disease activity in humans as well as mounting evidence from preclinical models demonstrate a role of B cells and humoral immunity in atherosclerotic cardiovascular disease. These include all aspects of B cell immunity, the generation of antigen-specific antibodies, antigen presentation and co-stimulation of T cells, as well as production of cytokines. Through their impact on adaptive and innate immune responses and the regulation of many other immune cells, B cells mediate both protective and detrimental effects in cardiovascular disease. Several antigens derived from (oxidised) lipoproteins, the vascular wall and classical autoantigens have been identified. The unique antibody responses they trigger and their relationship with atherosclerotic cardiovascular disease are reviewed. In particular, we focus on the different effector functions of specific IgM, IgG, and IgE antibodies and the cellular responses they trigger and highlight potential strategies to target B cell functions for therapy.
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Affiliation(s)
- Florentina Porsch
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
| | - Ziad Mallat
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom.,INSERM U970, Paris Cardiovascular Research Centre, Paris, France.,Unversité Paris Descartes, Sorbonne Paris Cité, Paris France
| | - Christoph J Binder
- Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria
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6
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Song X, Zou X, Ge W, Hou C, Cao Z, Zhao H, Zhang T, Jin L, Fu Y, Kong W, Yan C, Cai J, Wang J. Blocking FcγRIIB in Smooth Muscle Cells Reduces Hypertension. Circ Res 2021; 129:308-325. [PMID: 33980031 DOI: 10.1161/circresaha.120.318447] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
[Figure: see text].
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MESH Headings
- Animals
- Antibodies/pharmacology
- Antihypertensive Agents/pharmacology
- Blood Pressure/drug effects
- Case-Control Studies
- Disease Models, Animal
- Extracellular Signal-Regulated MAP Kinases/metabolism
- Female
- HEK293 Cells
- Humans
- Hypertension/genetics
- Hypertension/metabolism
- Hypertension/physiopathology
- Hypertension/prevention & control
- Immunoglobulin G/blood
- Male
- Mice, Inbred C57BL
- Mice, Knockout
- Middle Aged
- Muscle, Smooth, Vascular/metabolism
- Muscle, Smooth, Vascular/physiopathology
- Myocytes, Smooth Muscle/drug effects
- Myocytes, Smooth Muscle/metabolism
- Rats
- Receptor, Angiotensin, Type 1/metabolism
- Receptors, IgG/antagonists & inhibitors
- Receptors, IgG/genetics
- Receptors, IgG/metabolism
- Signal Transduction
- Vascular Remodeling/drug effects
- Mice
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Affiliation(s)
- Xiaomin Song
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Xuan Zou
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Weipeng Ge
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Cuiliu Hou
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Zhujie Cao
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Hongmei Zhao
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Tiantian Zhang
- Department Physiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (T.Z.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Ling Jin
- State Key Laboratory of Cardiovascular Disease, Beijing Key Laboratory for Molecular Diagnostics of Cardiovascular Diseases, Center of Laboratory Medicine, Fuwai Hospital, National Center for Cardiovascular Diseases (L.J., J.C.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Yi Fu
- Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Beijing, China (Y.F., W.K.)
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education (Y.F., W.K.)
| | - Wei Kong
- Physiology and Pathophysiology, School of Basic Medical Sciences, Peking University, Beijing, China (Y.F., W.K.)
- Key Laboratory of Molecular Cardiovascular Science, Ministry of Education (Y.F., W.K.)
| | - Chen Yan
- Aab Cardiovascular Research Institute, Medicine, University of Rochester School of Medicine and Dentistry, NY (C.Y.)
| | - Jun Cai
- State Key Laboratory of Cardiovascular Disease, Beijing Key Laboratory for Molecular Diagnostics of Cardiovascular Diseases, Center of Laboratory Medicine, Fuwai Hospital, National Center for Cardiovascular Diseases (L.J., J.C.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
| | - Jing Wang
- Department of Pathophysiology, State Key Laboratory of Medical Molecular Biology, Institute of Basic Medical Sciences (X.S., X.Z., W.G., C.H., Z.C., H.Z., J.W.), Chinese Academy of Medical Sciences, Peking Union Medical College, China
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7
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Asare Y, Koehncke J, Selle J, Simsekyilmaz S, Jankowski J, Shagdarsuren G, Gessner JE, Bernhagen J, Shagdarsuren E. Differential Role for Activating FcγRIII in Neointima Formation After Arterial Injury and Diet-Induced Chronic Atherosclerosis in Apolipoprotein E-Deficient Mice. Front Physiol 2020; 11:673. [PMID: 32625118 PMCID: PMC7313534 DOI: 10.3389/fphys.2020.00673] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 05/26/2020] [Indexed: 12/25/2022] Open
Abstract
Atherogenesis and arterial remodeling following mechanical injury are driven by inflammation and mononuclear cell infiltration. The binding of immune complexes (ICs) to immunoglobulin (Ig)-Fc gamma receptors (FcγRs) on most innate and adaptive immune cells induces a variety of inflammatory responses that promote atherogenesis. Here, we studied the role of FcγRIII in neointima formation after arterial injury in atherosclerosis-prone mice and compared the outcome and mechanism to that of FcγRIII in diet-induced “chronic” atherosclerosis. FcγrIII–/–/Apoe–/– and control Apoe–/– mice were subjected to wire-induced endothelial denudation of the carotid artery while on high-fat diet (HFD). FcγrIII deficiency mitigated neointimal plaque formation and lesional macrophage accumulation, and enhanced neointimal vascular smooth muscle cell (VSMC) numbers. This went along with a reduced expression of tumor necrosis factor-α (TNF-α), monocyte chemoattractant protein-1 (MCP-1/CCL2), and vascular cell adhesion molecule-1 (VCAM-1) in the neointimal lesions. Interestingly, in a chronic model of diet-induced atherosclerosis, we unraveled a dichotomic role of FcγRIII in an early versus advanced stage of the disease. While FcγrIII deficiency conferred atheroprotection in the early stage, it promoted atherosclerosis in advanced stages. To this end, FcγrIII deficiency attenuated pro-inflammatory responses in early atherosclerosis but promoted these events in advanced stages. Analysis of the mechanism(s) underlying the athero-promoting effect of FcγrIII deficiency in late-stage atherosclerosis revealed increased serum levels of anti-oxidized-LDL immunoglobulins IgG2c and IgG2b. This was paralleled by enhanced lesional accumulation of IgGs without affecting levels of complement-activated products C5a or C5ar1, FcγRII, and FcγRIV. Moreover, FcγrIII-deficient macrophages expressed more FcγrII, Tnf-α, and Il-1β mRNA when exposed to IgG1 or oxLDL-IgG1 ICs in vitro, and peripheral CD4+ and CD8+ T-cell levels were altered. Collectively, our data suggest that deficiency of activating FcγRIII limits neointima formation after arterial injury in atherosclerosis-prone mice as well as early stage chronic atherosclerosis, but augments late-stage atherosclerosis suggesting a dual role of FcγRIII in atherogenic inflammation.
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Affiliation(s)
- Yaw Asare
- Institute for Stroke and Dementia Research (ISD), LMU University Hospital, Ludwig Maximilian University of Munich (LMU), Munich, Germany.,Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany
| | - Janine Koehncke
- Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany
| | - Jaco Selle
- Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany.,Translational Experimental Pediatrics - Experimental Pulmonology, Department of Pediatric and Adolescent Medicine, University of Cologne, Cologne, Germany
| | - Sakine Simsekyilmaz
- Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany
| | - Joachim Jankowski
- Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany.,Experimental Vascular Pathology, Cardiovascular Research Institute Maastricht (CARIM), Maastricht University, Maastricht, Netherlands
| | - Gansuvd Shagdarsuren
- Department of Nephrology, School of Medicine, Mongolian National University of Medical Sciences, Ulaanbaatar, Mongolia
| | - Johannes E Gessner
- Molecular Immunology Research Unit, Clinical Department of Immunology and Rheumatology, Hannover Medical School, Hanover, Germany
| | - Jürgen Bernhagen
- Vascular Biology, Institute for Stroke and Dementia Research (ISD), LMU University Hospital, Ludwig Maximilian University of Munich (LMU), Munich, Germany.,Munich Heart Alliance, Munich, Germany
| | - Erdenechimeg Shagdarsuren
- Institute for Molecular Cardiovascular Research (IMCAR), University Hospital, RWTH Aachen University, Aachen, Germany.,Institute for Transplantation Diagnostics and Cell Therapeutics, University Hospital and Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
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8
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Xiang Y, Liang B, Zhang X, Zheng F. Lower HDL-C levels are associated with higher expressions of CD16 on monocyte subsets in coronary atherosclerosis. Int J Med Sci 2020; 17:2171-2179. [PMID: 32922178 PMCID: PMC7484662 DOI: 10.7150/ijms.47998] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 07/29/2020] [Indexed: 01/17/2023] Open
Abstract
Background: Increased expressions of CD16 on classical monocytes precede their transition to intermediate monocytes. Thus far, the influence of lipids on the expression of CD14 and CD16 on monocyte subsets in coronary atherosclerosis (CA) remains unclear. The aim of this study was to investigate the underlying association between blood lipids and the expression of CD14 and CD16 on monocyte subsets. Methods: This study enrolled 112 healthy controls and 110 CA patients. Monocyte subsets [CD14++CD16- (classical), CD14++CD16+ (intermediate) and CD14+CD16++ (non-classical)] were analyzed by flow cytometry. Median fluorescent intensity (MFI) was used to evaluate the expression levels of CD14 and CD16 on monocyte subsets. Results: Compared with the control group, the expression of CD16 was significantly increased on all three monocyte subsets in the patient group. Correlation analysis revealed that serum HDL-C was inversely associated with the expression of CD16 on intermediate monocytes after Bonferroni correction in the control group. In addition, a significant decrease in classical monocytes and an increase in intermediate monocytes were detected in patients. In linear regression analysis, intermediate monocytes showed an inverse association with serum HDL-C in the control group. Although CD14 was correlated with serum TC and HDL-C, there was no statistical difference in CD14 expression between the two groups. Conclusion: Low serum HDL-C may induce upregulation of CD16 on classical monocytes, which may in turn lead to the increase of intermediate monocytes in coronary atherosclerosis patients.
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Affiliation(s)
- Yang Xiang
- Center for Gene Diagnosis, and Clinical Lab, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan 430071, China
| | - Bin Liang
- Center for Gene Diagnosis, and Clinical Lab, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan 430071, China
| | - Xiaokang Zhang
- Center for Gene Diagnosis, and Clinical Lab, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan 430071, China
| | - Fang Zheng
- Center for Gene Diagnosis, and Clinical Lab, Zhongnan Hospital of Wuhan University, Donghu Road 169, Wuhan 430071, China
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10
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Maguire EM, Pearce SWA, Xiao Q. Foam cell formation: A new target for fighting atherosclerosis and cardiovascular disease. Vascul Pharmacol 2018; 112:54-71. [PMID: 30115528 DOI: 10.1016/j.vph.2018.08.002] [Citation(s) in RCA: 187] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2018] [Revised: 07/17/2018] [Accepted: 08/03/2018] [Indexed: 12/23/2022]
Abstract
During atherosclerosis, the gradual accumulation of lipids into the subendothelial space of damaged arteries results in several lipid modification processes followed by macrophage uptake in the arterial wall. The way in which these modified lipoproteins are dealt with determines the likelihood of cholesterol accumulation within the monocyte-derived macrophage and thus its transformation into the foam cell that makes up the characteristic fatty streak observed in the early stages of atherosclerosis. The unique expression of chemokine receptors and cellular adhesion molecules expressed on the cell surface of monocytes points to a particular extravasation route that they can take to gain entry into atherosclerotic site, in order to undergo differentiation into the phagocytic macrophage. Indeed several GWAS and animal studies have identified key genes and proteins required for monocyte recruitment as well cholesterol handling involving lipid uptake, cholesterol esterification and cholesterol efflux. A re-examination of the previously accepted paradigm of macrophage foam cell origin has been called into question by recent studies demonstrating shared expression of scavenger receptors, cholesterol transporters and pro-inflammatory cytokine release by alternative cell types present in the neointima, namely; endothelial cells, vascular smooth muscle cells and stem/progenitor cells. Thus, therapeutic targets aimed at a more heterogeneous foam cell population with shared functions, such as enhanced protease activity, and signalling pathways, mediated by non-coding RNA molecules, may provide greater therapeutic outcome in patients. Finally, studies targeting each aspect of foam cell formation and death using both genetic knock down and pharmacological inhibition have provided researchers with a clearer understanding of the cellular processes at play, as well as helped researchers to identify key molecular targets, which may hold significant therapeutic potential in the future.
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Affiliation(s)
- Eithne M Maguire
- Centre for Clinical Pharmacology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Stuart W A Pearce
- Centre for Clinical Pharmacology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK
| | - Qingzhong Xiao
- Centre for Clinical Pharmacology, William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, London, EC1M 6BQ, UK.
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11
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Cappellari R, D'Anna M, Bonora BM, Rigato M, Cignarella A, Avogaro A, Fadini GP. Shift of monocyte subsets along their continuum predicts cardiovascular outcomes. Atherosclerosis 2017; 266:95-102. [DOI: 10.1016/j.atherosclerosis.2017.09.032] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 09/20/2017] [Accepted: 09/28/2017] [Indexed: 11/29/2022]
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12
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Sage AP, Nus M, Bagchi Chakraborty J, Tsiantoulas D, Newland SA, Finigan AJ, Masters L, Binder CJ, Mallat Z. X-Box Binding Protein-1 Dependent Plasma Cell Responses Limit the Development of Atherosclerosis. Circ Res 2017; 121:270-281. [DOI: 10.1161/circresaha.117.310884] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 06/14/2017] [Accepted: 06/15/2017] [Indexed: 02/06/2023]
Abstract
Rationale:
Diverse B cell responses and functions may be involved in atherosclerosis. Protective antibody responses, such as those against oxidized lipid epitopes, are thought to mainly derive from T cell-independent innate B cell subsets. In contrast, both pathogenic and protective roles have been associated with T cell-dependent antibodies, and their importance in both humans and mouse models is still unclear.
Objective:
To specifically target antibody production by plasma cells and determine the impact on atherosclerotic plaque development in mice with and without CD4+ T cells.
Methods and Results:
We combined a model of specific antibody deficiency, B cell-specific CD79a-
Cre
x XBP1 (X-box binding protein-1) floxed mice (XBP1-conditional knockout), with antibody-mediated depletion of CD4+ T cells. Ldlr knockout mice transplanted with XBP1-conditional knockout (or wild-type control littermate) bone marrow were fed western diet for 8 weeks with or without anti-CD4 depletion. All groups had similar levels of serum cholesterol. In Ldlr/XBP1-conditional knockout mice, serum levels of IgG, IgE, and IgM were significantly attenuated, and local antibody deposition in atherosclerotic plaque was absent. Antibody deficiency significantly accelerated atherosclerosis at both the aortic root and aortic arch. T cell and monocyte responses were not modulated, but necrotic core size was greater, even when adjusting for plaque size, and collagen deposition significantly lower. Anti-CD4 depletion in Ldlr/wild-type mice led to a decrease of serum IgG1 and IgG2c but not IgG3, as well as decreased IgM, associated with increased atherosclerosis and necrotic cores, and a decrease in plaque collagen. The combination of antibody deficiency and anti-CD4 depletion has no additive effects on aortic root atherosclerosis.
Conclusions:
The endogenous T cell-dependent humoral response can be protective. This has important implications for novel vaccine strategies for atherosclerosis and in understanding the impacts of immunotherapies used in patients at high risk for cardiovascular disease.
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Affiliation(s)
- Andrew P. Sage
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Meritxell Nus
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Jayashree Bagchi Chakraborty
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Dimitrios Tsiantoulas
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Stephen A. Newland
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Alison J. Finigan
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Leanne Masters
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Christoph J. Binder
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
| | - Ziad Mallat
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, United Kingdom (A.P.S., M.N., J.B.C., S.A.N., A.J.F., L.M., Z.M.); Department of Laboratory Medicine, (D.T., C.J.B.); Medical University of Vienna, Austria (D.T., C.J.B.); CeMM Research Center for Molecular Medicine of the Austrian Academy of Sciences, Vienna (D.T., C.J.B.); INSERM U970, Paris Cardiovascular Research Center, France (Z.M.); and Université Paris Descartes, Sorbonne Paris Cité, France (Z.M.)
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Sun JB, Holmgren J, Cragg MS, Xiang Z. Lack of Fc Gamma Receptor IIIA Promotes Rather than Suppresses Humoral and Cellular Immune Responses after Mucosal or Parenteral Immunization with Antigen and Adjuvants. Scand J Immunol 2017; 85:264-271. [PMID: 28128471 DOI: 10.1111/sji.12528] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 01/18/2017] [Indexed: 11/28/2022]
Abstract
The Fcγ receptor IIIA (FcγRIIIA) has traditionally been known as a positive regulator of immune responses. Consistent with this, mice deficient in FcγRIIIA are protected from various inflammation-associated pathologies including several autoimmune diseases. In contrast to this accepted dogma, we show here that mice lacking FcγRIIIA developed increased rather than reduced both humoral and cellular immune responses to mucosal (sublingual) immunization with ovalbumin (OVA) given together with the strong mucosal adjuvant cholera toxin as well as to parenteral (subcutaneous) immunization with OVA in complete Freund's adjuvant. After either route of immunization, in comparison with concomitantly immunized wild-type mice, FcγRIIIA-/- mice had increased serum anti-OVA IgG (IgG1 but not IgG2) antibody responses as well as augmented cellular responses that included memory B cells and effector T cells. The increments in immune responses in FcγRIIIA-/- mice were similar to those seen in FcγRIIB-/- mice. Furthermore, OVA-pulsed FcγRIIIA-/- DCs, similar to OVA-specific FcγRIIB-/- DCs, had enhanced capacity to activate OVA-specific OT-II T cells, which was even further pronounced when DCs were pulsed with IgG1-complexed OVA. Our data support an inhibitory-regulatory role of FcγRIIIA on vaccine/adjuvant-induced immune responses and demonstrate that lack of FcγRIIIA can promote rather than suppress both humoral and cellular immune responses.
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Affiliation(s)
- J-B Sun
- Department of Microbiology and Immunology and University of Gothenburg Vaccine Research Institute (GUVAX), Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - J Holmgren
- Department of Microbiology and Immunology and University of Gothenburg Vaccine Research Institute (GUVAX), Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
| | - M S Cragg
- Antibody and Vaccine Group, Cancer Sciences Unit, Faculty of Medicine, Southampton General Hospital, University of Southampton, Southampton, Hampshire, UK
| | - Z Xiang
- Department of Microbiology and Immunology and University of Gothenburg Vaccine Research Institute (GUVAX), Institute of Biomedicine, Sahlgrenska Academy at University of Gothenburg, Göteborg, Sweden
- Department of Health Technology and Informatics, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hong Kong, China
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14
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Sage AP, Mallat Z. Readapting the adaptive immune response - therapeutic strategies for atherosclerosis. Br J Pharmacol 2017; 174:3926-3939. [PMID: 28052311 DOI: 10.1111/bph.13700] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2016] [Revised: 12/13/2016] [Accepted: 12/20/2016] [Indexed: 02/06/2023] Open
Abstract
Cardiovascular diseases remain a major global health issue, with the development of atherosclerosis as a major underlying cause. Our treatment of cardiovascular disease has improved greatly over the past three decades, but much remains to be done reduce disease burden. Current priorities include reducing atherosclerosis advancement to clinically significant stages and preventing plaque rupture or erosion. Inflammation and involvement of the adaptive immune system influences all these aspects and therefore is one focus for future therapeutic development. The atherosclerotic vascular wall is now recognized to be invaded from both sides (arterial lumen and adventitia), for better or worse, by the adaptive immune system. Atherosclerosis is also affected at several stages by adaptive immune responses, overall providing many opportunities to target these responses and to reduce disease progression. Protective influences that may be defective in diseased individuals include humoral responses to modified LDL and regulatory T cell responses. There are many strategies in development to boost these pathways in humans, including vaccine-based therapies. The effects of various existing adaptive immune targeting therapies, such as blocking critical co-stimulatory pathways or B cell depletion, on cardiovascular disease are beginning to emerge with important consequences for both autoimmune disease patients and the potential for wider use of such therapies. Entering the translation phase for adaptive immune targeting therapies is an exciting and promising prospect. LINKED ARTICLES This article is part of a themed section on Targeting Inflammation to Reduce Cardiovascular Disease Risk. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v174.22/issuetoc and http://onlinelibrary.wiley.com/doi/10.1111/bcp.v82.4/issuetoc.
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Affiliation(s)
- Andrew P Sage
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, UK
| | - Ziad Mallat
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, UK.,INSERM U970, Paris Cardiovascular Research Center, Paris, France, Université Paris Descartes, Sorbonne Paris Cité, Paris, France
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15
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Abstract
In the current era, one of the major factors limiting graft survival is chronic antibody-mediated rejection (ABMR), whilst patient survival is impacted by the effects of immunosuppression on susceptibility to infection, malignancy and atherosclerosis. IgG antibodies play a role in all of these processes, and many of their cellular effects are mediated by Fc gamma receptors (FcγRs). These surface receptors are expressed by most immune cells, including B cells, natural killer cells, dendritic cells and macrophages. Genetic variation in FCGR genes is likely to affect susceptibility to ABMR and to modulate the physiological functions of IgG. In this review, we discuss the potential role played by FcγRs in determining outcomes in solid organ transplantation, and how genetic polymorphisms in these receptors may contribute to variations in transplant outcome.
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Affiliation(s)
- Tomas Castro-Dopico
- Molecular Immunity Unit, Department of Medicine, MRC Laboratory of Molecular Biology, University of Cambridge, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH UK
| | - Menna R. Clatworthy
- Molecular Immunity Unit, Department of Medicine, MRC Laboratory of Molecular Biology, University of Cambridge, Francis Crick Avenue, Cambridge Biomedical Campus, Cambridge, CB2 0QH UK
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16
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Harmon EY, Fronhofer V, Keller RS, Feustel PJ, Zhu X, Xu H, Avram D, Jones DM, Nagarajan S, Lennartz MR. Anti-inflammatory immune skewing is atheroprotective: Apoe−/−FcγRIIb−/− mice develop fibrous carotid plaques. J Am Heart Assoc 2015; 3:e001232. [PMID: 25516435 PMCID: PMC4338708 DOI: 10.1161/jaha.114.001232] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Background Stroke, caused by carotid plaque rupture, is a major cause of death in the United States. Whereas vulnerable human plaques have higher Fc receptor (FcγR) expression than their stable counterparts, how FcγR expression impacts plaque histology is unknown. We investigated the role of FcγRIIb in carotid plaque development and stability in apolipoprotein (Apo)e−/− and Apoe−/−FcγRIIb−/− double knockout (DKO) animals. Methods and Results Plaques were induced by implantation of a shear stress‐modifying cast around the carotid artery. Plaque length and stenosis were followed longitudinally using ultrasound biomicroscopy. Immune status was determined by flow cytometry, cytokine release, immunoglobulin G concentration and analysis of macrophage polarization both in plaques and in vitro. Surprisingly, DKO animals had lower plaque burden in both carotid artery and descending aorta. Plaques from Apoe−/− mice were foam‐cell rich and resembled vulnerable human specimens, whereas those from DKO mice were fibrous and histologically stable. Plaques from DKO animals expressed higher arginase 1 (Arg‐1) and lower inducible nitric oxide synthase (iNOS), indicating the presence of M2 macrophages. Analysis of blood and cervical lymph nodes revealed higher interleukin (IL)‐10, immune complexes, and regulatory T cells (Tregs) and lower IL‐12, IL‐1β, and tumor necrosis factor alpha (TNF‐α) in DKO mice. Similarly, in vitro stimulation produced higher IL‐10 and Arg‐1 and lower iNOS, IL‐1β, and TNF‐α in DKO versus Apoe−/− macrophages. These results define a systemic anti‐inflammatory phenotype. Conclusions We hypothesized that removal of FcγRIIb would exacerbate atherosclerosis and generate unstable plaques. However, we found that deletion of FcγRIIb on a congenic C57BL/6 background induces an anti‐inflammatory Treg/M2 polarization that is atheroprotective.
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Affiliation(s)
- Erin Y Harmon
- Centers for Cell Biology and Cancer Research, Albany Medical College, Albany, NY
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17
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Sage AP, Nus M, Baker LL, Finigan AJ, Masters LM, Mallat Z. Regulatory B Cell–Specific Interleukin-10 Is Dispensable for Atherosclerosis Development in Mice. Arterioscler Thromb Vasc Biol 2015; 35:1770-3. [DOI: 10.1161/atvbaha.115.305568] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Accepted: 06/05/2015] [Indexed: 12/24/2022]
Affiliation(s)
- Andrew P. Sage
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
| | - Meritxell Nus
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
| | - Lauren L. Baker
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
| | - Alison J. Finigan
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
| | - Leanne M. Masters
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
| | - Ziad Mallat
- From the Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge, Cambridge, United Kingdom (A.P.S, M.S, L.L.B., A.J.F., L.M.M., Z.M.); and Institut National de la Sante et de la Recherche Medicale, Paris, France (Z.M.)
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18
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Ng HP, Zhu X, Harmon EY, Lennartz MR, Nagarajan S. Reduced Atherosclerosis in apoE-inhibitory FcγRIIb-Deficient Mice Is Associated With Increased Anti-Inflammatory Responses by T Cells and Macrophages. Arterioscler Thromb Vasc Biol 2015; 35:1101-12. [PMID: 25792447 PMCID: PMC4409543 DOI: 10.1161/atvbaha.115.305290] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 02/27/2015] [Indexed: 01/08/2023]
Abstract
OBJECTIVE Fcγ receptors (FcγRs) are classified as activating (FcγRI, III, and IV) and inhibitory (FcγRII) receptors. We have reported that deletion of activating FcγRs in apolipoprotein E (apoE) single knockout mice attenuated atherosclerosis. In this report, we investigated the hypothesis that deficiency of inhibitory FcγRIIb exacerbates atherosclerosis. APPROACH AND RESULTS ApoE-FcγRIIb double knockout mice, congenic to the C57BL/6 (apoE-FcγRIIbB6 (-/-)), were generated and atherosclerotic lesions were assessed. In contrary to our hypothesis, when compared with apoE single knockout mice, arterial lesions were significantly decreased in apoE-FcγRIIbB6 (-/-) male and female mice fed chow or high-fat diets. Chimeric mice generated by transplanting apoE-FcγRIIbB6 (-/-) marrow into apoE single knockout mice also developed reduced lesions. CD4(+) T cells from apoE-FcγRIIbB6 (-/-) mice produced higher levels of interleukin-10 and transforming growth factor-β than their apoE single knockout counterparts. As our findings conflict with a previous report using apoE-FcγRIIb129/B6 (-/-) mice on a mixed genetic background, we investigated whether strain differences contributed to the anti-inflammatory response. Macrophages from FcγRIIb129/B6 (-/-) mice on a mixed genetic background produced more interleukin-1β and MCP-1 (monocyte chemoattractant protein-1) in response to immune complexes, whereas congenic FcγRIIbB6 (-/-) mice generated more interleukin-10 and significantly less interleukin-1β. Interestingly, the expression of lupus-associated slam genes, located in proximity to fcgr2b in mouse chromosome 1, is upregulated only in mixed FcγRIIb129/B6 (-/-) mice. CONCLUSIONS Our findings demonstrate a detrimental role for FcγRIIb signaling in atherosclerosis and the contribution of anti-inflammatory cytokine responses in the attenuated lesions observed in apoE-FcγRIIbB6 (-/-) mice. As 129/sv genome-derived lupus-associated genes have been implicated in lupus phenotype in FcγRIIb129/B6 (-/-) mice, our findings suggest possible epistatic mechanism contributing to the decreased lesions.
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Affiliation(s)
- Hang Pong Ng
- From the Department of Pathology, Vascular Medicine Institute, University of Pittsburgh, PA (H.P.N., X.Z., S.N.); Department of Microbiology and Immunology (H.P.N., S.N.), University of Arkansas for Medical Sciences, Little Rock; and Center for Cell Biology and Cancer Research, Albany Medical College, NY (E.Y.H., M.R.L.)
| | - Xinmei Zhu
- From the Department of Pathology, Vascular Medicine Institute, University of Pittsburgh, PA (H.P.N., X.Z., S.N.); Department of Microbiology and Immunology (H.P.N., S.N.), University of Arkansas for Medical Sciences, Little Rock; and Center for Cell Biology and Cancer Research, Albany Medical College, NY (E.Y.H., M.R.L.)
| | - Erin Y Harmon
- From the Department of Pathology, Vascular Medicine Institute, University of Pittsburgh, PA (H.P.N., X.Z., S.N.); Department of Microbiology and Immunology (H.P.N., S.N.), University of Arkansas for Medical Sciences, Little Rock; and Center for Cell Biology and Cancer Research, Albany Medical College, NY (E.Y.H., M.R.L.)
| | - Michelle R Lennartz
- From the Department of Pathology, Vascular Medicine Institute, University of Pittsburgh, PA (H.P.N., X.Z., S.N.); Department of Microbiology and Immunology (H.P.N., S.N.), University of Arkansas for Medical Sciences, Little Rock; and Center for Cell Biology and Cancer Research, Albany Medical College, NY (E.Y.H., M.R.L.)
| | - Shanmugam Nagarajan
- From the Department of Pathology, Vascular Medicine Institute, University of Pittsburgh, PA (H.P.N., X.Z., S.N.); Department of Microbiology and Immunology (H.P.N., S.N.), University of Arkansas for Medical Sciences, Little Rock; and Center for Cell Biology and Cancer Research, Albany Medical College, NY (E.Y.H., M.R.L.).
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19
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Wilhelm AJ, Rhoads JP, Wade NS, Major AS. Dysregulated CD4+ T cells from SLE-susceptible mice are sufficient to accelerate atherosclerosis in LDLr-/- mice. Ann Rheum Dis 2015; 74:778-85. [PMID: 24395554 PMCID: PMC4083014 DOI: 10.1136/annrheumdis-2013-203759] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2013] [Revised: 11/30/2013] [Accepted: 12/15/2013] [Indexed: 12/25/2022]
Abstract
OBJECTIVE Accelerated atherosclerosis is a major source of morbidity in systemic lupus erythematosus (SLE). However, the cause of SLE-accelerated atherosclerosis remains unclear. METHODS CD4(+) T cells from C57/Bl/6 (B6) or SLE-susceptible B6.Sle1.2.3 (B6.SLE) mice were transferred into LDLr(-/-), Rag(-/-) mice. T cells were examined for cytokine production and expression of interleukin-10 receptor (IL-10R) and functional markers. T cells were isolated based on FoxP3(GFP) expression and transferred to LDLr(-/-), Rag(-/-) mice to establish a role for B6.SLE effector T cells (Teff) in atherosclerosis. RESULTS Mice receiving whole B6.SLE CD4(+) T cells displayed no other SLE phenotype; however, atherosclerosis was increased nearly 40%. We noted dysregulated IL-17 production and reduced frequency of IL-10R expression by B6.SLE regulatory T cells (Treg). Functional assays indicated resistance of B6.SLE Teff to suppression by both B6.SLE and B6 Treg. Transfer experiments with CD4(+)FoxP3(-) Teff and CD4(+)FoxP3(+) Treg from B6.SLE and B6 mice, respectively, resulted in increased atherosclerosis compared with B6 Teff and Treg recipients. Treg isolated from mice receiving B6.SLE Teff with B6 Treg had increased production of IL-17 and fewer expressed IL-10R compared with B6 Teff and Treg transfer. CONCLUSIONS Transfer of B6.SLE Teff to LDLr(-/-), Rag(-/-) mice results in accelerated atherosclerosis independent of the source of Treg. In addition, the presence of B6.SLE Teff resulted in more IL-17-producing Treg and fewer expressing IL-10R, suggesting that B6.SLE Teff may mediate phenotypic changes in Treg. To our knowledge, this is the first study to provide direct evidence of the role of B6.SLE Teff in accelerating atherosclerosis through resistance to Treg suppression.
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MESH Headings
- Animals
- Atherosclerosis/genetics
- Atherosclerosis/immunology
- Atherosclerosis/metabolism
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- Disease Models, Animal
- Forkhead Transcription Factors/metabolism
- Lupus Erythematosus, Systemic/genetics
- Lupus Erythematosus, Systemic/immunology
- Lupus Erythematosus, Systemic/metabolism
- Mice
- Mice, Inbred Strains
- Mice, Knockout
- Receptors, Interleukin-10/metabolism
- Receptors, LDL/genetics
- T-Lymphocyte Subsets
- T-Lymphocytes, Regulatory/immunology
- T-Lymphocytes, Regulatory/metabolism
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Affiliation(s)
- Ashley J Wilhelm
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Jillian P Rhoads
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Nekeithia S Wade
- Department of Microbiology, Carter Center for Immunology Research, University of Virginia, Charlottesville, Virginia, USA
| | - Amy S Major
- Division of Cardiovascular Medicine, Department of Medicine, Vanderbilt University Medical Center, Nashville, Tennessee, USA
- Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, Tennessee, USA
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Tanigaki K, Sundgren N, Khera A, Vongpatanasin W, Mineo C, Shaul PW. Fcγ receptors and ligands and cardiovascular disease. Circ Res 2015; 116:368-84. [PMID: 25593280 DOI: 10.1161/circresaha.116.302795] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Fcγ receptors (FcγRs) classically modulate intracellular signaling on binding of the Fc region of IgG in immune response cells. How FcγR and their ligands affect cardiovascular health and disease has been interrogated recently in both preclinical and clinical studies. The stimulation of activating FcγR in endothelial cells, vascular smooth muscle cells, and monocytes/macrophages causes a variety of cellular responses that may contribute to vascular disease pathogenesis. Stimulation of the lone inhibitory FγcR, FcγRIIB, also has adverse consequences in endothelial cells, antagonizing NO production and reparative mechanisms. In preclinical disease models, activating FcγRs promote atherosclerosis, whereas FcγRIIB is protective, and activating FcγRs also enhance thrombotic and nonthrombotic vascular occlusion. The FcγR ligand C-reactive protein (CRP) has undergone intense study. Although in rodents CRP does not affect atherosclerosis, it causes hypertension and insulin resistance and worsens myocardial infarction. Massive data have accumulated indicating an association between increases in circulating CRP and coronary heart disease in humans. However, Mendelian randomization studies reveal that CRP is not likely a disease mediator. CRP genetics and hypertension warrant further investigation. To date, studies of genetic variants of activating FcγRs are insufficient to implicate the receptors in coronary heart disease pathogenesis in humans. However, a link between FcγRIIB and human hypertension may be emerging. Further knowledge of the vascular biology of FcγR and their ligands will potentially enhance our understanding of cardiovascular disorders, particularly in patients whose greater predisposition for disease is not explained by traditional risk factors, such as individuals with autoimmune disorders.
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Affiliation(s)
- Keiji Tanigaki
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Nathan Sundgren
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Amit Khera
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Wanpen Vongpatanasin
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Chieko Mineo
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas
| | - Philip W Shaul
- From the Department of Pediatrics, Center for Pulmonary and Vascular Biology (K.T., N.S., C.M., P.W.S.), and Division of Cardiology, Department of Internal Medicine (A.K., W.V.), University of Texas Southwestern Medical Center, Dallas.
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Abstract
The development of atherosclerosis is the major etiological factor causing cardiovascular disease and constitutes a lipid-induced, chronic inflammatory and autoimmune disease of the large arteries. A long-standing view of the protective role of B cells in atherosclerosis has been challenged by recent studies using B cell depletion in animal models. Whereas complete B cell deficiency increases atherosclerosis, depletion of B2 but not B1 cells reduces atherosclerosis. This has led to a re-evaluation of the multiple potential pathways by which B cells can regulate atherosclerosis, and the apparent opposing roles of B1 and B2 cells. B cells, in addition to having the unique ability to produce antibodies, are now recognized to play a number of important roles in the immune system, including cytokine production and direct regulation of T cell responses. This review summarizes current knowledge on B cell subsets and functions, and how these could distinctly influence atherosclerosis development.
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Affiliation(s)
- Andrew P Sage
- Division of Cardiovascular Medicine, Department of Medicine, University of Cambridge , Cambridge , UK
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22
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Zhu X, Ng HP, Lai YC, Craigo JK, Nagilla PS, Raghani P, Nagarajan S. Scavenger receptor function of mouse Fcγ receptor III contributes to progression of atherosclerosis in apolipoprotein E hyperlipidemic mice. THE JOURNAL OF IMMUNOLOGY 2014; 193:2483-95. [PMID: 25038257 DOI: 10.4049/jimmunol.1303075] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Recent studies showed loss of CD36 or scavenger receptor-AI/II (SR-A) does not ameliorate atherosclerosis in a hyperlipidemic mouse model, suggesting receptors other than CD36 and SR-A may also contribute to atherosclerosis. In this report, we show that apolipoprotein E (apoE)-CD16 double knockout (DKO; apoE-CD16 DKO) mice have reduced atherosclerotic lesions compared with apoE knockout mice. In vivo and in vitro foam cell analyses showed apoE-CD16 DKO macrophages accumulated less neutral lipids. Reduced foam cell formation in apoE-CD16 DKO mice is not due to change in expression of CD36, SR-A, and LOX-1. This led to a hypothesis that CD16 may have scavenger receptor activity. We presented evidence that a soluble form of recombinant mouse CD16 (sCD16) bound to malondialdehyde-modified low-density lipoprotein (MDALDL), and this binding is blocked by molar excess of MDA- modified BSA and anti-MDA mAbs, suggesting CD16 specifically recognizes MDA epitopes. Interestingly, sCD16 inhibited MDALDL binding to macrophage cell line, as well as soluble forms of recombinant mouse CD36, SR-A, and LOX-1, indicating CD16 can cross-block MDALDL binding to other scavenger receptors. Anti-CD16 mAb inhibited immune complex binding to sCD16, whereas it partially inhibited MDALDL binding to sCD16, suggesting MDALDL binding site may be in close proximity to the immune complex binding site in CD16. Loss of CD16 expression resulted in reduced levels of MDALDL-induced proinflammatory cytokine expression. Finally, CD16-deficient macrophages showed reduced MDALDL-induced Syk phosphorylation. Collectively, our findings suggest scavenger receptor activity of CD16 may, in part, contribute to the progression of atherosclerosis.
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Affiliation(s)
- Xinmei Zhu
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Hang Pong Ng
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Yen-Chun Lai
- Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Jodi K Craigo
- Center for Vaccine Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Pruthvi S Nagilla
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261
| | - Pooja Raghani
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Summer Undergraduate Research Program, University of Pittsburgh, Pittsburgh, PA 15261; and Arizona State University, Tempe, AZ 85287
| | - Shanmugam Nagarajan
- Department of Pathology, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Vascular Medicine Institute, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261; Center for Vaccine Research, University of Pittsburgh School of Medicine, Pittsburgh, PA 15261;
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23
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Abstract
Insights into the important contribution of inflammation and immune functions in the development and progression of atherosclerosis have greatly improved our understanding of this disease. Although the role of T cells has been extensively studied for decades, only recently has the role of B cells gained more attention. Recent studies have identified differential effects of different B-cell subsets and helped to clarify the still poorly understood mechanisms by which these act. B1 cells have been shown to prevent lesion formation, whereas B2 cells have been suggested to promote it. Natural IgM antibodies, mainly derived from B1 cells, have been shown to mediate atheroprotective effects, but the functional role of other immunoglobulin classes, particularly IgG, still remains elusive. In this review, we will focus on recent insights on the role of B cells and various immunoglobulin classes and how these may mediate their effects in atherosclerotic lesion formation. Moreover, we will highlight potential therapeutic approaches focusing on B-cell depletion that could be used to translate experimental evidence to human disease.
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Affiliation(s)
- Dimitrios Tsiantoulas
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Cody J Diehl
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Joseph L Witztum
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.)
| | - Christoph J Binder
- From the Center for Molecular Medicine (CeMM) of the Austrian Academy of Sciences, Vienna, Austria (D.T., C.J.B.); Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (D.T., C.J.B.); and Department of Medicine, University of California San Diego, La Jolla (C.J.D., J.L.W.).
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24
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Abstract
At least 468 individual genes have been manipulated by molecular methods to study their effects on the initiation, promotion, and progression of atherosclerosis. Most clinicians and many investigators, even in related disciplines, find many of these genes and the related pathways entirely foreign. Medical schools generally do not attempt to incorporate the relevant molecular biology into their curriculum. A number of key signaling pathways are highly relevant to atherogenesis and are presented to provide a context for the gene manipulations summarized herein. The pathways include the following: the insulin receptor (and other receptor tyrosine kinases); Ras and MAPK activation; TNF-α and related family members leading to activation of NF-κB; effects of reactive oxygen species (ROS) on signaling; endothelial adaptations to flow including G protein-coupled receptor (GPCR) and integrin-related signaling; activation of endothelial and other cells by modified lipoproteins; purinergic signaling; control of leukocyte adhesion to endothelium, migration, and further activation; foam cell formation; and macrophage and vascular smooth muscle cell signaling related to proliferation, efferocytosis, and apoptosis. This review is intended primarily as an introduction to these key signaling pathways. They have become the focus of modern atherosclerosis research and will undoubtedly provide a rich resource for future innovation toward intervention and prevention of the number one cause of death in the modern world.
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Affiliation(s)
- Paul N Hopkins
- Cardiovascular Genetics, Department of Internal Medicine, University of Utah, Salt Lake City, Utah, USA.
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25
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Witztum JL, Lichtman AH. The influence of innate and adaptive immune responses on atherosclerosis. ANNUAL REVIEW OF PATHOLOGY-MECHANISMS OF DISEASE 2013; 9:73-102. [PMID: 23937439 DOI: 10.1146/annurev-pathol-020712-163936] [Citation(s) in RCA: 204] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Both the chronic development of atherosclerotic lesions and the acute changes in lesion phenotype that lead to clinical cardiovascular events are significantly influenced by the innate and adaptive immune responses to lipoprotein deposition and oxidation in the arterial wall. The rapid pace of discovery of mechanisms of immunologic recognition, effector functions, and regulation has significantly influenced the study of atherosclerosis, and our new knowledge is beginning to affect how we treat this ubiquitous disease. In this review, we discuss recent advances in our understanding of how innate and adaptive immunity contribute to atherosclerosis, as well as therapeutic opportunities that arise from this knowledge.
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Affiliation(s)
- Joseph L Witztum
- Department of Medicine, University of California, San Diego, La Jolla, California 92093;
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26
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Mallavia B, Oguiza A, Lopez-Franco O, Recio C, Ortiz-Muñoz G, Lazaro I, Lopez-Parra V, Egido J, Gomez-Guerrero C. Gene Deficiency in Activating Fcγ Receptors Influences the Macrophage Phenotypic Balance and Reduces Atherosclerosis in Mice. PLoS One 2013; 8:e66754. [PMID: 23805273 PMCID: PMC3689671 DOI: 10.1371/journal.pone.0066754] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2012] [Accepted: 05/10/2013] [Indexed: 01/18/2023] Open
Abstract
Immunity contributes to arterial inflammation during atherosclerosis. Oxidized low-density lipoproteins induce an autoimmune response characterized by specific antibodies and immune complexes in atherosclerotic patients. We hypothesize that specific Fcγ receptors for IgG constant region participate in atherogenesis by regulating the inflammatory state of lesional macrophages. In vivo we examined the role of activating Fcγ receptors in atherosclerosis progression using bone marrow transplantation from mice deficient in γ-chain (the common signaling subunit of activating Fcγ receptors) to hyperlipidemic mice. Hematopoietic deficiency of Fcγ receptors significantly reduced atherosclerotic lesion size, which was associated with decreased number of macrophages and T lymphocytes, and increased T regulatory cell function. Lesions of Fcγ receptor deficient mice exhibited increased plaque stability, as evidenced by higher collagen and smooth muscle cell content and decreased apoptosis. These effects were independent of changes in serum lipids and antibody response to oxidized low-density lipoproteins. Activating Fcγ receptor deficiency reduced pro-inflammatory gene expression, nuclear factor-κB activity, and M1 macrophages at the lesion site, while increasing anti-inflammatory genes and M2 macrophages. The decreased inflammation in the lesions was mirrored by a reduced number of classical inflammatory monocytes in blood. In vitro, lack of activating Fcγ receptors attenuated foam cell formation, oxidative stress and pro-inflammatory gene expression, and increased M2-associated genes in murine macrophages. Our study demonstrates that activating Fcγ receptors influence the macrophage phenotypic balance in the artery wall of atherosclerotic mice and suggests that modulation of Fcγ receptor-mediated inflammatory responses could effectively suppress atherosclerosis.
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Affiliation(s)
- Beñat Mallavia
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Ainhoa Oguiza
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Oscar Lopez-Franco
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Carlota Recio
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Guadalupe Ortiz-Muñoz
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Cardiovascular Research Institute, University of California San Francisco, San Francisco, California, United States of America
| | - Iolanda Lazaro
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Virginia Lopez-Parra
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Jesus Egido
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
| | - Carmen Gomez-Guerrero
- Renal and Vascular Inflammation Lab, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- Nephrology Department, IIS-Fundacion Jimenez Diaz, Autonoma University, Madrid, Spain
- * E-mail:
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27
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Lichtman AH, Binder CJ, Tsimikas S, Witztum JL. Adaptive immunity in atherogenesis: new insights and therapeutic approaches. J Clin Invest 2013; 123:27-36. [PMID: 23281407 DOI: 10.1172/jci63108] [Citation(s) in RCA: 149] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Many remarkable advances have improved our understanding of the cellular and molecular events in the pathogenesis of atherosclerosis. Chief among these is the accumulating knowledge of how the immune system contributes to all phases of atherogenesis, including well-known inflammatory reactions consequent to intimal trapping and oxidation of LDL. Advances in our understanding of the innate and adaptive responses to these events have helped to clarify the role of inflammation in atherogenesis and suggested new diagnostic modalities and novel therapeutic targets. Here we focus on recent advances in understanding how adaptive immunity affects atherogenesis.
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Affiliation(s)
- Andrew H Lichtman
- Vascular Research Division, Department of Pathology, Brigham and Women’s Hospital, and Harvard Medical School, Boston, Massachusetts 02115, USA.
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28
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Perry HM, Bender TP, McNamara CA. B cell subsets in atherosclerosis. Front Immunol 2012; 3:373. [PMID: 23248624 PMCID: PMC3518786 DOI: 10.3389/fimmu.2012.00373] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2012] [Accepted: 11/21/2012] [Indexed: 12/21/2022] Open
Abstract
Atherosclerosis, the underlying cause of heart attacks and strokes, is a chronic inflammatory disease of the artery wall. Immune cells, including lymphocytes modulate atherosclerotic lesion development through interconnected mechanisms. Elegant studies over the past decades have begun to unravel a role for B cells in atherosclerosis. Recent findings provide evidence that B cell effects on atherosclerosis may be subset-dependent. B-1a B cells have been reported to protect from atherosclerosis by secretion of natural IgM antibodies. Conventional B-2 B cells can promote atherosclerosis through less clearly defined mechanism that may involve CD4 T cells. Yet, there may be other populations of B cells within these subsets with different phenotypes altering their impact on atherosclerosis. Additionally, the role of B cell subsets in atherosclerosis may depend on their environmental niche and/or the stage of atherogenesis. This review will highlight key findings in the evolving field of B cells and atherosclerosis and touch on the potential and importance of translating these findings to human disease.
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Affiliation(s)
- Heather M Perry
- Department of Pathology, University of Virginia Charlottesville, VA, USA ; Cardiovascular Research Center, University of Virginia Health System Charlottesville, VA, USA
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29
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Chang SH, Johns M, Boyle JJ, McConnell E, Kirkham PA, Bicknell C, Zahoor-ul-Hassan Dogar M, Edwards RJ, Gale-Grant O, Khamis R, Ramkhelawon KVV, Haskard DO. Model IgG monoclonal autoantibody-anti-idiotype pair for dissecting the humoral immune response to oxidized low density lipoprotein. Hybridoma (Larchmt) 2012; 31:87-98. [PMID: 22509912 DOI: 10.1089/hyb.2011.0058] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Increasing evidence implicates IgG autoantibodies against oxidized forms of low density lipoprotein (oxLDL) in the pathophysiology of atherosclerotic arterial disease. However, insufficient knowledge of their structure and function is a key gap. Using an elderly LDL receptor-deficient atherosclerotic mouse, we isolated a novel IgG3k against oxLDL (designated MAb LO1). LO1 reacts with copper-oxidized LDL, but minimally with native LDL. Further analysis showed that MAb LO1 also reacts in vitro with malondialdehyde-conjugated LDL (MDA-LDL), a known key epitope in copper-oxidized LDL preparations. By screening a phage library expressing single chain variable region antibodies (scFv), we selected an anti-idiotype scFv (designated H3) that neutralizes MAb LO1 binding to MDA-LDL. Amino acid substitutions between H3 and an irrelevant control scFv C12 showed that residues in the H3 CDRH2, CDRH3, and CDRL2 are all critical for MAb LO1 binding, consistent with a conformational epitope on H3 involving both heavy and light chains. Comparison of amino acids in H3 CDRH2 and CDRL2 with apoB, the major LDL protein, showed homologous sequences, suggesting H3 has structural similarities to the MAb LO1 binding site on MDA-LDL. Immunocytochemical staining showed that MAb LO1 binds epitopes in mouse and human atherosclerotic lesions. The MAb LO1-H3 combination therefore provides a very promising model for analyzing the structure and function of an individual IgG autoantibody in relation to atherosclerosis.
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Affiliation(s)
- Shang-Hung Chang
- Vascular Sciences Section, Department of Medicine, Imperial College, Hammersmith Hospital, London, United Kingdom
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30
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Potential cardiovascular disease risk markers among HIV-infected women initiating antiretroviral treatment. J Acquir Immune Defic Syndr 2012; 60:359-68. [PMID: 22592585 DOI: 10.1097/qai.0b013e31825b03be] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Inflammation and hemostasis perturbation may be involved in vascular complications of HIV infection. We examined atherogenic biomarkers and subclinical atherosclerosis in HIV-infected adults before and after beginning highly active antiretroviral therapy (HAART). METHODS In the Women's Interagency HIV Study, 127 HIV-infected women studied pre and post HAART were matched to HIV-uninfected controls. Six semiannual measurements of soluble CD14, tumor necrosis factor (TNF) alfa, soluble interleukin (IL) 2 receptor, IL-6, IL-10, monocyte chemoattractant protein 1, D-dimer, and fibrinogen were obtained. Carotid artery intima-media thickness was measured by B-mode ultrasound. RESULTS Relative to HIV-uninfected controls, HAART-naive HIV-infected women had elevated levels of soluble CD14 (1945 vs 1662 ng/mL, Wilcoxon signed rank P < 0.0001), TNF-α (6.3 vs 3.4 pg/mL, P < 0.0001), soluble IL-2 receptor (1587 vs 949 pg/mL, P < 0.0001), IL-10 (3.3 vs 1.9 pg/mL, P < 0.0001), monocyte chemoattractant protein 1 (190 vs 163 pg/mL, P < 0.0001), and D-dimer (0.43 vs 0.31 μg/mL, P < 0.01). Elevated biomarker levels declined after HAART. Although most biomarkers normalized to HIV-uninfected levels, in women on effective HAART, TNF-α levels remained elevated compared with HIV-uninfected women (+0.8 pg/mL, P = 0.0002). Higher post-HAART levels of soluble IL-2 receptor (P = 0.02), IL-6 (P = 0.05), and D-dimer (P = 0.03) were associated with increased carotid artery intima-media thickness. CONCLUSIONS Untreated HIV infection is associated with abnormal hemostasis (eg, D-dimer), proatherogenic (eg, TNF-α), and antiatherogenic (eg, IL-10) inflammatory markers. HAART reduces most inflammatory mediators to HIV-uninfected levels. Increased inflammation and hemostasis are associated with subclinical atherosclerosis in recently treated women. These findings have potential implications for long-term risk of cardiovascular disease in HIV-infected patients, even with effective therapy.
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31
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Wang X, Liu X, Kishimoto C, Yuan Z. The role of Fcγ receptors in atherosclerosis. Exp Biol Med (Maywood) 2012; 237:609-16. [PMID: 22688821 DOI: 10.1258/ebm.2012.011373] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Atherosclerosis is widely considered to be an immune-mediated process. Fcγ receptors (Fcγ Rs) contribute to the regulation of a multitude of immune and inflammatory responses and are implicated in human atherosclerotic lesions. Major cell types involved in the pathogenesis of atherosclerosis express Fcγ Rs and their proatherogenic ligands such as immune complexes and C-reactive protein, which act to activate Fcγ R signaling pathways. This review summarizes recent significant progress addressing the multifaceted roles of Fcγ Rs in atherogenesis which comes from the studies of Fcγ R-deficient animal models, clinical investigations and in vitro molecular and cellular studies. These new findings help us appreciate the emerging role of Fcγ Rs in atherosclerosis, and suggest Fcγ Rs as a potential therapeutic target for atherosclerosis.
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Affiliation(s)
- Xinhong Wang
- Department of Cardiovascular Medicine, First Affiliated Hospital of Medical School, Xi'an Jiaotong University, 277 Yanta West Road, Xi'an, China
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32
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Boyle JJ, Christou I, Iqbal MB, Nguyen AT, Leung VWY, Evans PC, Liu Y, Johns M, Kirkham P, Haskard DO. Solid-phase immunoglobulins IgG and IgM activate macrophages with solid-phase IgM acting via a novel scavenger receptor a pathway. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 181:347-61. [PMID: 22658487 DOI: 10.1016/j.ajpath.2012.03.040] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Revised: 02/26/2012] [Accepted: 03/20/2012] [Indexed: 01/21/2023]
Abstract
IgG may accelerate atherosclerosis via ligation of proinflammatory Fcγ receptors; however, IgM is unable to ligate FcγR and is often considered vasculoprotective. IgM aggravates ischemia-reperfusion injury, and solid-phase deposits of pure IgM, as seen with IgM-secreting neoplasms, are well known clinically to provoke vascular inflammation. We therefore examined the molecular mechanisms by which immunoglobulins can aggravate vascular inflammation, such as in atherosclerosis. We compared the ability of fluid- and solid-phase immunoglobulins to activate macrophages. Solid-phase immunoglobulins initiated prothrombotic and proinflammatory functions in human macrophages, including NF-κB p65 activation, H(2)O(2) secretion, macrophage-induced apoptosis, and tissue factor expression. Responses to solid-phase IgG (but not to IgM) were blocked by neutralizing antibodies to CD16 (FcγRIII), consistent with its known role. Macrophages from mice deficient in macrophage scavenger receptor A (SR-A; CD204) had absent IgM binding and no activation by solid-phase IgM. RNA interference-mediated knockdown of SR-A in human macrophages suppressed activation by solid-phase IgM. IgM binding to SR-A was demonstrated by both co-immunoprecipitation studies and the binding of fluorescently labeled IgM to SR-A-transfected cells. Immunoglobulins on solid-phase particles around macrophages were found in human plaques, increased in ruptured plaques compared with stable ones. These observations indicate that solid-phase IgM and IgG can activate macrophages and destabilize vulnerable plaques. Solid-phase IgM activates macrophages via a novel SR-A pathway.
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Affiliation(s)
- Joseph J Boyle
- Vascular Sciences Section, National Heart and Lung Institute, Imperial College London, London, United Kingdom.
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33
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Stylianou IM, Bauer RC, Reilly MP, Rader DJ. Genetic basis of atherosclerosis: insights from mice and humans. Circ Res 2012; 110:337-55. [PMID: 22267839 DOI: 10.1161/circresaha.110.230854] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Atherosclerosis is a complex and heritable disease involving multiple cell types and the interactions of many different molecular pathways. The genetic and molecular mechanisms of atherosclerosis have, in part, been elucidated by mouse models; at least 100 different genes have been shown to influence atherosclerosis in mice. Importantly, unbiased genome-wide association studies have recently identified a number of novel loci robustly associated with atherosclerotic coronary artery disease. Here, we review the genetic data elucidated from mouse models of atherosclerosis, as well as significant associations for human coronary artery disease. Furthermore, we discuss in greater detail some of these novel human coronary artery disease loci. The combination of mouse and human genetics has the potential to identify and validate novel genes that influence atherosclerosis, some of which may be candidates for new therapeutic approaches.
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Affiliation(s)
- Ioannis M Stylianou
- Institute for Translational Medicine and Therapeutics, University of Pennsylvania School of Medicine, 654 BRBII/III Labs, 421 Curie Boulevard, Philadelphia, Pennsylvania, 19104-6160, USA
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34
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Ng HP, Burris RL, Nagarajan S. Attenuated atherosclerotic lesions in apoE-Fcγ-chain-deficient hyperlipidemic mouse model is associated with inhibition of Th17 cells and promotion of regulatory T cells. THE JOURNAL OF IMMUNOLOGY 2011; 187:6082-93. [PMID: 22043015 DOI: 10.4049/jimmunol.1004133] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Though the presence of antioxidized low-density lipoprotein IgG is well documented in clinical and animal studies, the role for FcγRs to the progression of atherosclerosis has not been studied in detail. In the current study, we investigated the role for activating FcγR in the progression of atherosclerosis using apolipoprotein E (apoE)-Fcγ-chain double-knockout (DKO) mice. Relative to apoE knockout (KO) mice, arterial lesion formation was significantly decreased in apoE-Fcγ-chain DKO mice. Bone marrow chimera studies showed reduced lesions in apoE KO mice receiving the bone marrow of apoE-Fcγ-chain DKO mice. Compared to apoE KO mice, antioxidized low-density lipoprotein IgG1 (Th2) and IgG2a (Th1), IL-10, and IFN-γ secretion by activated T cells was increased in apoE-Fcγ-chain DKO mice. These findings suggest that reduced atherosclerotic lesion in apoE-Fcγ-chain DKO mice is not due to a Th1/Th2 imbalance. Interestingly, the number of Th17 cells and the secretion of IL-17 by activated CD4(+) cells were decreased in apoE-Fcγ-chain DKO mice. Notably, the number of regulatory T cells, expression of mRNA, and secretion of TGF-β and IL-10 were increased in apoE-Fcγ-chain DKO mice. Furthermore, secretions of IL-6 and STAT-3 phosphorylation essential for Th17 cell genesis were reduced in apoE-Fcγ-chain DKO mice. Importantly, decrease in Th17 cells in apoE-Fcγ-chain DKO mice was due to reduced IL-6 release by APC of apoE-Fcγ-chain DKO mice. Collectively, our data suggest that activating FcγR promotes atherosclerosis by inducing a Th17 response in the hyperlipidemic apoE KO mouse model.
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Affiliation(s)
- Hang Pong Ng
- Arkansas Children's Nutrition Center, University of Arkansas for Medical Sciences, Little Rock, AR 72202, USA
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35
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Affiliation(s)
- Christoph J. Binder
- From the Center for Molecular Medicine of the Austrian Academy of Sciences (C.J.B.), Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (C.J.B.); Department of Medicine, University of California, San Diego, La Jolla, CA (C.J.B., J.L.W.)
| | - Joseph L. Witztum
- From the Center for Molecular Medicine of the Austrian Academy of Sciences (C.J.B.), Department of Laboratory Medicine, Medical University of Vienna, Vienna, Austria (C.J.B.); Department of Medicine, University of California, San Diego, La Jolla, CA (C.J.B., J.L.W.)
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36
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Lennartz MR, Aggarwal A, Michaud TM, Feustel PJ, Jones DM, Brosnan MJ, Keller RS, Loegering DJ, Kreienberg PB. Ligation of macrophage Fcγ receptors recapitulates the gene expression pattern of vulnerable human carotid plaques. PLoS One 2011; 6:e21803. [PMID: 21814555 PMCID: PMC3140977 DOI: 10.1371/journal.pone.0021803] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2011] [Accepted: 06/07/2011] [Indexed: 11/24/2022] Open
Abstract
Stroke is a leading cause of death in the United States. As ∼60% of strokes result from carotid plaque rupture, elucidating the mechanisms that underlie vulnerability is critical for therapeutic intervention. We tested the hypothesis that stable and vulnerable human plaques differentially express genes associated with matrix degradation. Examination established that femoral, and the distal region of carotid, plaques were histologically stable while the proximal carotid plaque regions were vulnerable. Quantitative RT-PCR was used to compare expression of 22 genes among these tissues. Distal carotid and femoral gene expression was not significantly different, permitting the distal carotid segments to be used as a paired control for their corresponding proximal regions. Analysis of the paired plaques revealed differences in 16 genes that impact plaque stability: matrix metalloproteinases (MMP, higher in vulnerable), MMP modulators (inhibitors: lower, activators: higher in vulnerable), activating Fc receptors (FcγR, higher in vulnerable) and FcγR signaling molecules (higher in vulnerable). Surprisingly, the relative expression of smooth muscle cell and macrophage markers in the three plaque types was not significantly different, suggesting that macrophage distribution and/or activation state correlates with (in)stability. Immunohistochemistry revealed that macrophages and smooth muscle cells localize to distinct and non-overlapping regions in all plaques. MMP protein localized to macrophage-rich regions. In vitro, treatment of macrophages with immune complexes, but not oxidized low density lipoprotein, C-reactive protein, or TNF-α, induced a gene expression profile similar to that of the vulnerable plaques. That ligation of FcγR recapitulates the pattern of gene expression in vulnerable plaques suggests that the FcγR → macrophage activation pathway may play a greater role in human plaque vulnerability than previously appreciated.
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Affiliation(s)
- Michelle R Lennartz
- Center for Cell Biology and Cancer Research, Albany Medical College, Albany, New York, United States of America.
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The inhibitory FcγRIIb modulates the inflammatory response and influences atherosclerosis in male apoE(-/-) mice. Atherosclerosis 2010; 214:73-80. [PMID: 21084088 DOI: 10.1016/j.atherosclerosis.2010.10.018] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 10/05/2010] [Accepted: 10/11/2010] [Indexed: 01/18/2023]
Abstract
BACKGROUND Atherosclerosis is widely accepted as an inflammatory disease involving both innate and adaptive immunity. B cells and/or antibodies have previously been shown to play a protective role against atherosclerosis. Aside from their ability to bind to antigens, antibodies can influence inflammatory responses by interacting with various Fcγ receptors on the surface of antigen presenting cells. Although studies in mice have determined that stimulatory Fcγ receptors contribute to atherosclerosis, the role of the inhibitory Fcγ receptor IIb (FcγRIIb) has only recently been investigated. METHODS AND RESULTS To determine the importance of FcγRIIb in modulating the adaptive immune response to hyperlipidemia, we generated FcγRIIb-deficient mice on the apoE-deficient background (apoE/FcγRIIb(-/-)). We report that male apoE/FcγRIIb(-/-) mice develop exacerbated atherosclerosis that is independent of lipid levels, and is characterized by increased antibody titers to modified LDL and pro-inflammatory cytokines in the aorta. CONCLUSIONS These findings suggest that antibodies against atherosclerosis-associated antigens partially protect against atherosclerosis in male apoE(-/-) mice by conveying inhibitory signals through the FcγRIIb that downregulate pro-inflammatory signaling via other immune receptors. These data are the first to describe a significant in vivo effect for FcγRIIb in modulating the cytokine response in the aorta in male apoE(-/-) mice.
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