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Li J, Wang F, Li Z, Feng J, Men Y, Han J, Xia J, Zhang C, Han Y, Chen T, Zhao Y, Zhou S, Da Y, Chai G, Hao J. Integrative multi-omics analysis identifies genetically supported druggable targets and immune cell specificity for myasthenia gravis. J Transl Med 2024; 22:302. [PMID: 38521921 PMCID: PMC10960998 DOI: 10.1186/s12967-024-04994-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 02/12/2024] [Indexed: 03/25/2024] Open
Abstract
BACKGROUND Myasthenia gravis (MG) is a chronic autoimmune disorder characterized by fluctuating muscle weakness. Despite the availability of established therapies, the management of MG symptoms remains suboptimal, partially attributed to lack of efficacy or intolerable side-effects. Therefore, new effective drugs are warranted for treatment of MG. METHODS By employing an analytical framework that combines Mendelian randomization (MR) and colocalization analysis, we estimate the causal effects of blood druggable expression quantitative trait loci (eQTLs) and protein quantitative trait loci (pQTLs) on the susceptibility of MG. We subsequently investigated whether potential genetic effects exhibit cell-type specificity by utilizing genetic colocalization analysis to assess the interplay between immune-cell-specific eQTLs and MG risk. RESULTS We identified significant MR results for four genes (CDC42BPB, CD226, PRSS36, and TNFSF12) using cis-eQTL genetic instruments and three proteins (CTSH, PRSS8, and CPN2) using cis-pQTL genetic instruments. Six of these loci demonstrated evidence of colocalization with MG susceptibility (posterior probability > 0.80). We next undertook genetic colocalization to investigate cell-type-specific effects at these loci. Notably, we identified robust evidence of colocalization, with a posterior probability of 0.854, linking CTSH expression in TH2 cells and MG risk. CONCLUSIONS This study provides crucial insights into the genetic and molecular factors associated with MG susceptibility, singling out CTSH as a potential candidate for in-depth investigation and clinical consideration. It additionally sheds light on the immune-cell regulatory mechanisms related to the disease. However, further research is imperative to validate these targets and evaluate their feasibility for drug development.
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Affiliation(s)
- Jiao Li
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
- Beijing Municipal Geriatric Medical Research Center, Beijing, China
- Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
| | - Fei Wang
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
- Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China
| | - Zhen Li
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Jingjing Feng
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Yi Men
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Jinming Han
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Jiangwei Xia
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Chen Zhang
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Yilai Han
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Teng Chen
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Yinan Zhao
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Sirui Zhou
- Department of Human Genetics, McGill University, Montréal, QC, Canada
| | - Yuwei Da
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China
| | - Guoliang Chai
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China.
- Beijing Municipal Geriatric Medical Research Center, Beijing, China.
| | - Junwei Hao
- Department of Neurology, Xuanwu Hospital, National Center for Neurological Disorders, Capital Medical University, Beijing, 100053, China.
- Beijing Municipal Geriatric Medical Research Center, Beijing, China.
- Key Laboratory for Neurodegenerative Diseases of Ministry of Education, Beijing, China.
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2
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Bhandari V, Bril V. FcRN receptor antagonists in the management of myasthenia gravis. Front Neurol 2023; 14:1229112. [PMID: 37602255 PMCID: PMC10439012 DOI: 10.3389/fneur.2023.1229112] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 07/19/2023] [Indexed: 08/22/2023] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disorder characterized by autoantibodies specifically directed against proteins located within the postsynaptic membrane of the neuromuscular junction. These pathogenic autoantibodies can be reduced by therapies such as plasma exchange, IVIG infusions and other immunosuppressive agents. However, there are significant side effects associated with most of these therapies. Since there is a better understanding of the molecular structure and the biological properties of the neonatal Fc receptors (FcRn), it possesses an attractive profile in treating myasthenia gravis. FcRn receptors prevent the catabolism of IgG by impeding their lysosomal degradation and facilitating their extracellular release at physiological pH, consequently extending the IgG half-life. Thus, the catabolism of IgG can be enhanced by blocking the FcRn, leading to outcomes similar to those achieved through plasma exchange with no significant safety concerns. The available studies suggest that FcRn holds promise as a versatile therapeutic intervention, capable of delivering beneficial outcomes in patients with distinct characteristics and varying degrees of MG severity. Efgartigimod is already approved for the treatment of generalized MG, rozanolixizumab is under review by health authorities, and phase 3 trials of nipocalimab and batoclimab are underway. Here, we will review the available data on FcRn therapeutic agents in the management of MG.
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Affiliation(s)
| | - Vera Bril
- Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital, University Health Network, University of Toronto, Toronto, ON, Canada
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3
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Abstract
INTRODUCTION Myasthenia gravis (MG) is an autoimmune disease where muscle antibodies form against the acetylcholine receptor (AChR), MuSK, or LRP4 at the neuromuscular junction leading to weakness. Patients worry about consequences for pregnancy, giving birth, nursing, and child outcome. AREAS COVERED This review lists the pharmacological treatments for MG in the reproductive age and gives recommendations. Consequences for pregnancy, giving birth, breastfeeding, and child outcome are discussed. EXPERT OPINION Pyridostigmine, corticosteroids in low doses, and azathioprine are regarded as safe during pregnancy and should be continued. Mycophenolate mofetil, methotrexate, and cyclophosphamide should not be used in reproductive age. Rituximab should not be given during pregnancy. Other monoclonal IgG antibodies such as eculizumab and efgartigimod should be given only when regarded strictly necessary to avoid long-term and severe incapacity. Intravenous and subcutaneous immunoglobulin and plasma exchange are safe treatments during pregnancy and are recommended for exacerbations with moderate or severe generalized weakness. Most MG women have spontaneous vaginal deliveries. Indications for Cesarean section are obstetrical and similar to non-MG women. Neonatal myasthenia manifests as a transient weakness caused by the mother's IgG muscle antibodies and affects 10% of the babies. MG women should be supported in their wish to have children.
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Affiliation(s)
- Nils Erik Gilhus
- Department of Neurology, Haukeland University Hospital, Bergen, Norway.,Department of Clinical Medicine, University of Bergen, Bergen, Norway
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4
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Abstract
Myasthenia gravis is an autoimmune disorder caused by antibodies against elements in the postsynaptic membrane at the neuromuscular junction, which leads to muscle weakness. Congenital myasthenic syndromes are rare and caused by mutations affecting pre- or postsynaptic function at the neuromuscular synapse and resulting in muscle weakness. MG has a prevalence of 150-250 and an annual incidence of 8-10 individuals per million. The majority has disease onset after age 50 years. Juvenile MG with onset in early childhood is more common in East Asia. MG is subgrouped according to type of pathogenic autoantibodies, age of onset, thymus pathology, and generalization of muscle weakness. More than 80% have antibodies against the acetylcholine receptor. The remaining have antibodies against MuSK, LRP4, or postsynaptic membrane antigens not yet identified. A thymoma is present in 10% of MG patients, and more than one-third of thymoma patients develop MG as a paraneoplastic condition. Immunosuppressive drug therapy, thymectomy, and symptomatic drug therapy with acetylcholine esterase inhibitors represent cornerstones in the treatment. The prognosis is good, with the majority of patients having mild or moderate symptoms only. Most congenital myasthenic syndromes are due to dysfunction in the postsynaptic membrane. Symptom debut is in early life. Symptomatic drug treatment has sometimes a positive effect.
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Affiliation(s)
- Nils Erik Gilhus
- Department of Neurology, Haukeland University Hospital and Department of Clinical Medicine, University of Bergen, Bergen, Norway.
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5
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Abstract
BACKGROUND Around 60%--75% of myasthenia gravis (MG) patients initially present with nonspecific ocular symptoms. Failed recognition of these symptoms may delay the diagnosis of MG up to 5 years or more, leading to a reduced likelihood of remission and increased morbidity. Current diagnostic tests are either poorly sensitive for patients presenting with ocular symptoms alone or are time consuming, invasive, require a high level of technical expertise, and generally are universally difficult to obtain. This review will explore quantitative eye and pupil tracking as a potential noninvasive, time-effective, and less technically demanding alternative to current diagnostic tests of MG. EVIDENCE ACQUISITION Comprehensive literature review. RESULTS Thirty-two publications using oculography for the diagnosis of MG and 6 studies using pupillometry were evaluated. In MG patients, extra ocular muscle fatigue was evident in reports of intersaccadic, intrasaccadic and postsaccadic abnormalities, changes in optokinetic nystagmus, slow eye movements, disconjugate saccades, and pupillary constrictor muscle weakness. CONCLUSIONS Our review identified several potentially useful variables that derive from oculography and pupillometry studies that could assist with a timely diagnosis of MG. Limitations of this review include heterogeneity in design, sample size, and quality of the studies evaluated. There is a need for larger, well-designed studies evaluating eye-tracking measures in the diagnosis of MG, especially for patients presenting with purely ocular symptoms.
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6
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Chen P, Tang X. Gut Microbiota as Regulators of Th17/Treg Balance in Patients With Myasthenia Gravis. Front Immunol 2022; 12:803101. [PMID: 35003133 PMCID: PMC8732367 DOI: 10.3389/fimmu.2021.803101] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/07/2021] [Indexed: 12/12/2022] Open
Abstract
Myasthenia gravis (MG) is an acquired neurological autoimmune disorder characterized by dysfunctional transmission at the neuromuscular junction, with its etiology associated with genetic and environmental factors. Anti-inflammatory regulatory T cells (Tregs) and pro-inflammatory T helper 17 (Th17) cells functionally antagonize each other, and the immune imbalance between them contributes to the pathogenesis of MG. Among the numerous factors influencing the balance of Th17/Treg cells, the gut microbiota have received attention from scholars. Gut microbial dysbiosis and altered microbial metabolites have been seen in patients with MG. Therefore, correcting Th17/Treg imbalances may be a novel therapeutic approach to MG by modifying the gut microbiota. In this review, we initially review the association between Treg/Th17 and the occurrence of MG and subsequently focus on recent findings on alterations of gut microbiota and microbial metabolites in patients with MG. We also explore the effects of gut microbiota on Th17/Treg balance in patients with MG, which may provide a new direction for the prevention and treatment of this disease.
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Affiliation(s)
- Pan Chen
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Xiangqi Tang
- Department of Neurology, The Second Xiangya Hospital, Central South University, Changsha, China
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7
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NKT and NKT-like Cells in Autoimmune Neuroinflammatory Diseases-Multiple Sclerosis, Myasthenia Gravis and Guillain-Barre Syndrome. Int J Mol Sci 2021; 22:ijms22179520. [PMID: 34502425 PMCID: PMC8431671 DOI: 10.3390/ijms22179520] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 08/27/2021] [Accepted: 08/27/2021] [Indexed: 12/14/2022] Open
Abstract
NKT cells comprise three subsets—type I (invariant, iNKT), type II, and NKT-like cells, of which iNKT cells are the most studied subset. They are capable of rapid cytokine production after the initial stimulus, thus they may be important for polarisation of Th cells. Due to this, they may be an important cell subset in autoimmune diseases. In the current review, we are summarising results of NKT-oriented studies in major neurological autoimmune diseases—multiple sclerosis, myasthenia gravis, and Guillain-Barre syndrome and their corresponding animal models.
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8
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Topaloudi A, Zagoriti Z, Flint AC, Martinez MB, Yang Z, Tsetsos F, Christou YP, Lagoumintzis G, Yannaki E, Zamba-Papanicolaou E, Tzartos J, Tsekmekidou X, Kotsa K, Maltezos E, Papanas N, Papazoglou D, Passadakis P, Roumeliotis A, Roumeliotis S, Theodoridis M, Thodis E, Panagoutsos S, Yovos J, Stamatoyannopoulos J, Poulas K, Kleopa K, Tzartos S, Georgitsi M, Paschou P. Myasthenia gravis genome-wide association study implicates AGRN as a risk locus. J Med Genet 2021; 59:801-809. [PMID: 34400559 DOI: 10.1136/jmedgenet-2021-107953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2021] [Accepted: 07/20/2021] [Indexed: 11/04/2022]
Abstract
BACKGROUND Myasthenia gravis (MG) is a rare autoimmune disorder affecting the neuromuscular junction (NMJ). Here, we investigate the genetic architecture of MG via a genome-wide association study (GWAS) of the largest MG data set analysed to date. METHODS We performed GWAS meta-analysis integrating three different data sets (total of 1401 cases and 3508 controls). We carried out human leucocyte antigen (HLA) fine-mapping, gene-based and tissue enrichment analyses and investigated genetic correlation with 13 other autoimmune disorders as well as pleiotropy across MG and correlated disorders. RESULTS We confirmed the previously reported MG association with TNFRSF11A (rs4369774; p=1.09×10-13, OR=1.4). Furthermore, gene-based analysis revealed AGRN as a novel MG susceptibility gene. HLA fine-mapping pointed to two independent MG loci: HLA-DRB1 and HLA-B. MG onset-specific analysis reveals differences in the genetic architecture of early-onset MG (EOMG) versus late-onset MG (LOMG). Furthermore, we find MG to be genetically correlated with type 1 diabetes (T1D), rheumatoid arthritis (RA), late-onset vitiligo and autoimmune thyroid disease (ATD). Cross-disorder meta-analysis reveals multiple risk loci that appear pleiotropic across MG and correlated disorders. DISCUSSION Our gene-based analysis identifies AGRN as a novel MG susceptibility gene, implicating for the first time a locus encoding a protein (agrin) that is directly relevant to NMJ activation. Mutations in AGRN have been found to underlie congenital myasthenic syndrome. Our results are also consistent with previous studies highlighting the role of HLA and TNFRSF11A in MG aetiology and the different risk genes in EOMG versus LOMG. Finally, we uncover the genetic correlation of MG with T1D, RA, ATD and late-onset vitiligo, pointing to shared underlying genetic mechanisms.
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Affiliation(s)
- Apostolia Topaloudi
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Zoi Zagoriti
- Department of Pharmacy, University of Patras, Rio, Greece
| | - Alyssa Camille Flint
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
| | | | - Zhiyu Yang
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
| | - Fotis Tsetsos
- Department of Molecular Biology and Genetics, Democritus University of Thrace, Alexandroupoli, Greece
| | | | | | - Evangelia Yannaki
- Department of Hematology, George Papanicolaou Hospital, Thessaloniki, Greece
| | - Eleni Zamba-Papanicolaou
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Neuroepidemiology and Centre for Neuromuscular Disorders, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, Nicosia, Cyprus
| | | | - Xanthippi Tsekmekidou
- Division of Endocrinology and Metabolism-Diabetes Center, 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Kalliopi Kotsa
- Division of Endocrinology and Metabolism-Diabetes Center, 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Efstratios Maltezos
- Diabetes Center, 2nd Department of Internal Medicine, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Nikolaos Papanas
- Diabetes Center, 2nd Department of Internal Medicine, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Dimitrios Papazoglou
- Diabetes Center, 2nd Department of Internal Medicine, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Ploumis Passadakis
- Department of Nephrology, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Athanasios Roumeliotis
- Division of Nephrology and Hypertension, 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Stefanos Roumeliotis
- Division of Nephrology and Hypertension, 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Marios Theodoridis
- Department of Nephrology, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Elias Thodis
- Department of Nephrology, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - Stylianos Panagoutsos
- Department of Nephrology, Alexandroupolis University General Hospital, Democritus University of Thrace, Alexandroupoli, Greece
| | - John Yovos
- Division of Endocrinology and Metabolism-Diabetes Center, 1st Department of Internal Medicine, AHEPA University Hospital, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - John Stamatoyannopoulos
- Departments of Medicine and Genome Sciences, University of Washington, Seattle, Washington, USA
| | | | - Kleopas Kleopa
- The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus.,Department of Neuroscience and Centre for Neuromuscular Disorders, The Cyprus Institute of Neurology and Genetics and Cyprus School of Molecular Medicine, Nicosia, Cyprus
| | - Socrates Tzartos
- Department of Pharmacy, University of Patras, Rio, Greece.,Hellenic Pasteur Institute, Athens, Greece
| | - Marianthi Georgitsi
- 1st Laboratory of Medical Biology-Genetics, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Peristera Paschou
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, USA
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9
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Nakamura Y, Sato H, Miyano Y, Murakami R, Motoki M, Shigekiyo T, Sugino M, Arawaka S. Whole-exome sequencing and human leukocyte antigen analysis in familial myasthenia gravis with thymoma: Case report and literature review. Clin Neurol Neurosurg 2021; 208:106864. [PMID: 34388596 DOI: 10.1016/j.clineuro.2021.106864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/17/2021] [Accepted: 07/30/2021] [Indexed: 10/20/2022]
Abstract
Myasthenia gravis (MG) is an autoimmune disease characterized by impaired neurotransmission at the neuromuscular junction. MG is generally non-inherited but is rarely inherited. Here, we report two patients with MG in the same pedigree: a 62-year-old Japanese man and his 46-year-old daughter who were positive for anti-acetylcholine receptor antibodies and had thymoma. We performed whole-exome sequencing (WES) and human leukocyte antigen (HLA) analyses to investigate the genetic contribution to familial onset. WES analysis of both patients showed no known variations in candidate genes for familial MG, and HLA analysis failed to detect HLA haplotypes seen in early-onset and late-onset MG. These findings suggest the presence of an unknown genetic background. Previous genetic studies on familial MG have identified ENOX1 and IFNGR1 as candidate genes in patients without thymoma, whereas no studies have identified candidate genes in patients with thymoma. To explore causative genes, it may be necessary to consider whether the genetic background differs between patients with and without thymoma in familial autoimmune MG.
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Affiliation(s)
- Yoshitsugu Nakamura
- Department of Internal Medicine IV, Division of Neurology, Osaka Medical and Pharmaceutical University Faculty of Medicine, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
| | - Hidenori Sato
- Genome Informatics Unit, Institution for Promotion of Medical Science Research, Yamagata University Faculty of Medicine, 2-2 Iida-Nishi, Yamagata 990-9585, Japan.
| | - Yuki Miyano
- Genome Informatics Unit, Institution for Promotion of Medical Science Research, Yamagata University Faculty of Medicine, 2-2 Iida-Nishi, Yamagata 990-9585, Japan.
| | - Ryoko Murakami
- Genome Informatics Unit, Institution for Promotion of Medical Science Research, Yamagata University Faculty of Medicine, 2-2 Iida-Nishi, Yamagata 990-9585, Japan.
| | - Mikiko Motoki
- Department of Internal Medicine IV, Division of Neurology, Osaka Medical and Pharmaceutical University Faculty of Medicine, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
| | - Taro Shigekiyo
- Department of Internal Medicine IV, Division of Neurology, Osaka Medical and Pharmaceutical University Faculty of Medicine, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
| | - Masakazu Sugino
- Division of Neurology, Aino Hospital, 11-18 Takadacho, Ibaraki, Osaka 567-0011, Japan.
| | - Shigeki Arawaka
- Department of Internal Medicine IV, Division of Neurology, Osaka Medical and Pharmaceutical University Faculty of Medicine, 2-7 Daigaku-machi, Takatsuki, Osaka 569-8686, Japan.
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10
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Creary LE, Gangavarapu S, Caillier SJ, Cavalcante P, Frangiamore R, Lie BA, Bengtsson M, Harbo HF, Brauner S, Hollenbach JA, Oksenberg JR, Bernasconi P, Maniaol AH, Hammarström L, Mantegazza R, Fernández-Viña MA. Next-Generation Sequencing Identifies Extended HLA Class I and II Haplotypes Associated With Early-Onset and Late-Onset Myasthenia Gravis in Italian, Norwegian, and Swedish Populations. Front Immunol 2021; 12:667336. [PMID: 34163474 PMCID: PMC8215161 DOI: 10.3389/fimmu.2021.667336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 04/27/2021] [Indexed: 11/13/2022] Open
Abstract
Genetic susceptibility to myasthenia gravis (MG) associates with specific HLA alleles and haplotypes at the class I and II regions in various populations. Previous studies have only examined alleles at a limited number of HLA loci that defined only broad serotypes or alleles defined at the protein sequence level. Consequently, genetic variants in noncoding and untranslated HLA gene segments have not been fully explored but could also be important determinants for MG. To gain further insight into the role of HLA in MG, we applied next-generation sequencing to analyze sequence variation at eleven HLA genes in early-onset (EO) and late-onset (LO) non-thymomatous MG patients positive for the acetylcholine receptor (AChR) antibodies and ethnically matched controls from Italy, Norway, and Sweden. For all three populations, alleles and haplotype blocks present on the ancestral haplotype AH8.1 were associated with risk in AChR-EOMG patients. HLA-B*08:01:01:01 was the dominant risk allele in Italians (OR = 3.28, P = 1.83E-05), Norwegians (OR = 3.52, P = 4.41E-16), and in Swedes HLA-B*08:01 was the primary risk allele (OR = 4.24, P <2.2E-16). Protective alleles and haplotype blocks were identified on the HLA-DRB7, and HLA-DRB13.1 class II haplotypes in Italians and Norwegians, whereas in Swedes HLA-DRB7 exhibited the main protective effect. For AChR-LOMG patients, the HLA-DRB15.1 haplotype and associated alleles were significantly associated with susceptibility in all groups. The HLA-DR13-HLA-DR-HLA-DQ haplotype was associated with protection in all AChR-LOMG groups. This study has confirmed and extended previous findings that the immunogenetic predisposition profiles for EOMG and LOMG are distinct. In addition, the results are consistent with a role for non-coding HLA genetic variants in the pathogenesis of MG.
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Affiliation(s)
- Lisa E Creary
- Department of Pathology, Stanford University School of Medicine, Palo Alto, CA, United States.,Histocompatibility, Immunogenetics and Disease Profiling Laboratory, Stanford Blood Center, Palo Alto, CA, United States
| | - Sridevi Gangavarapu
- Histocompatibility, Immunogenetics and Disease Profiling Laboratory, Stanford Blood Center, Palo Alto, CA, United States
| | - Stacy J Caillier
- Department of Neurology, School of Medicine, University of California San Francisco, San Francisco, CA, United States
| | - Paola Cavalcante
- Neurology IV Unit Neuroimmunology and Neuromuscular Diseases, Fondazione I.R.C.C.S Istituto Neurologico Carlo Besta (INCB), Milan, Italy
| | - Rita Frangiamore
- Neurology IV Unit Neuroimmunology and Neuromuscular Diseases, Fondazione I.R.C.C.S Istituto Neurologico Carlo Besta (INCB), Milan, Italy
| | - Benedicte A Lie
- Department of Immunology and Transfusion Medicine, Oslo University Hospital, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway.,Department of Medical Genetics, University of Oslo and Oslo University Hospital, Oslo, Norway
| | - Mats Bengtsson
- Department of Immunology, Genetics and Pathology (IGP), Rudbeck Laboratory, Uppsala University and University Hospital, Uppsala, Sweden
| | - Hanne Flinstad Harbo
- Department of Neurology, Oslo University Hospital and University of Oslo, Oslo, Norway
| | - Susanna Brauner
- Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden
| | - Jill A Hollenbach
- Department of Neurology, School of Medicine, University of California San Francisco, San Francisco, CA, United States
| | - Jorge R Oksenberg
- Department of Neurology, School of Medicine, University of California San Francisco, San Francisco, CA, United States
| | - Pia Bernasconi
- Neurology IV Unit Neuroimmunology and Neuromuscular Diseases, Fondazione I.R.C.C.S Istituto Neurologico Carlo Besta (INCB), Milan, Italy
| | | | - Lennart Hammarström
- The Department of Laboratory Medicine, Karolinska Institutet, Stockholm, Sweden
| | - Renato Mantegazza
- Neurology IV Unit Neuroimmunology and Neuromuscular Diseases, Fondazione I.R.C.C.S Istituto Neurologico Carlo Besta (INCB), Milan, Italy.,Department of Clinical Research and Innovation, Fondazione I.R.C.C.S Istituto Neurologico Carlo Besta (INCB), Milan, Italy
| | - Marcelo A Fernández-Viña
- Department of Pathology, Stanford University School of Medicine, Palo Alto, CA, United States.,Histocompatibility, Immunogenetics and Disease Profiling Laboratory, Stanford Blood Center, Palo Alto, CA, United States
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11
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Zhao R, Luo S, Zhao C. The role of innate immunity in myasthenia gravis. Autoimmun Rev 2021; 20:102800. [PMID: 33722749 DOI: 10.1016/j.autrev.2021.102800] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Accepted: 01/22/2021] [Indexed: 12/19/2022]
Abstract
Myasthenia gravis (MG) is a T cell-driven, B cell-mediated and autoantibody-dependent autoimmune disorder against neuromuscular junctions (NMJ). Accumulated evidence has emerged regarding the role of innate immunity in the pathogenesis of MG. In this review, we proposed two hypothesis underlying the pathological mechanism. In the context of gene predisposition, on the one hand, Toll-like receptors (TLRs) pathways were initiated by viral infection in the thymus with MG to generate chemokines and pro-inflammatory cytokines such as Type I interferon (IFN), which facilitate the thymus to function as a tertiary lymphoid organ (TLO). On the another hand, the antibodies against acetylcholine receptors (AChR) generated by thymus then activated the classical pathways on thymus and neuromuscular junction (NMJ). Futher, we also highlight the role of innate immune cells in the pathogenic response. Finally, we provide some future perspectives in developing new therapeutic approaches particularly targeting the innate immunity for MG.
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Affiliation(s)
- Rui Zhao
- Department of Neurology, Huashan hospital Fudan University, 200040 Shanghai, China
| | - Sushan Luo
- Department of Neurology, Huashan hospital Fudan University, 200040 Shanghai, China
| | - Chongbo Zhao
- Department of Neurology, Huashan hospital Fudan University, 200040 Shanghai, China.
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Lotan I, Benninger F, Hellmann MA, Sicsic C, Brenner T, Kahana E, Steiner I. Incidence of AChR Ab-positive myasthenia gravis in Israel: A population-based study. Acta Neurol Scand 2020; 142:66-73. [PMID: 32145067 DOI: 10.1111/ane.13239] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Revised: 02/27/2020] [Accepted: 03/03/2020] [Indexed: 11/29/2022]
Abstract
BACKGROUND The incidence of myasthenia gravis (MG) has traditionally been low, ranging between 2-6/106 . Several recent epidemiological studies have reported a higher incidence. We, therefore, aimed to assess and characterize the incidence of MG in Israel. METHODS We retrospectively reviewed the records of all four laboratories that performed the acetylcholine receptor antibody (AChR Ab) test in Israel between 1994 and 2013 and documented the number of newly diagnosed seropositive MG patients each year. To assure that data indeed reflect only newly diagnosed patients, patient's names and ID numbers were screened at the Hadassah medical center database since 1978, the year when the test was first performed in Israel. In order to calculate the annual incidence of the disease, the population at risk was derived from the annual publication of the Israeli Central Bureau of Statistics. RESULTS The annual incidence of MG for this time period was 13.1/106 inhabitants. The mean incidence of MG between 1994 and 2003 was 7.695/106 /y, while the mean incidence between 2004 and 2013 was 18.49/106 (P < .0001). Mean age of diagnosis between 1994 and 2003 was 56.65 ± 0.9351, while between 2004 and 2013, it was 59.89 ± 0.5336 (P = .0012). Male to female (M:F) incidence ratio in the years 1994-2003 and 2004-2013 was 2:3.2 and 3:1.8, respectively, reflecting increased incidence among males (P < .0001). CONCLUSIONS The incidence of MG in Israel has increased significantly during the last decade, especially among males of older age. These findings may reflect an etiological role of an environmental factor, increased awareness, and increased longevity in general.
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Affiliation(s)
- Itay Lotan
- Department of Neurology Rabin Medical Center Beilinson Campus Petach Tikva Israel
- Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel
| | - Felix Benninger
- Department of Neurology Rabin Medical Center Beilinson Campus Petach Tikva Israel
- Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel
| | - Mark A. Hellmann
- Department of Neurology Rabin Medical Center Beilinson Campus Petach Tikva Israel
- Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel
| | - Camille Sicsic
- Laboratory of Neuroimmunology Department of Neurology The Agnes –Ginges Center for Neurogenetics Hebrew University Hadassah Medical Center Jerusalem Israel
| | - Talma Brenner
- Laboratory of Neuroimmunology Department of Neurology The Agnes –Ginges Center for Neurogenetics Hebrew University Hadassah Medical Center Jerusalem Israel
| | - Ester Kahana
- Department of Neurology Barzilai Medical Center Ashkelon Israel
- Faculty of Health Sciences Ben‐Gurion University of the Negev Beer Sheva Israel
| | - Israel Steiner
- Department of Neurology Rabin Medical Center Beilinson Campus Petach Tikva Israel
- Sackler Faculty of Medicine Tel Aviv University Tel Aviv Israel
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Abstract
Myasthenia gravis (MG) is an autoimmune disease caused by antibodies against the acetylcholine receptor (AChR), muscle-specific kinase (MuSK) or other AChR-related proteins in the postsynaptic muscle membrane. Localized or general muscle weakness is the predominant symptom and is induced by the antibodies. Patients are grouped according to the presence of antibodies, symptoms, age at onset and thymus pathology. Diagnosis is straightforward in most patients with typical symptoms and a positive antibody test, although a detailed clinical and neurophysiological examination is important in antibody-negative patients. MG therapy should be ambitious and aim for clinical remission or only mild symptoms with near-normal function and quality of life. Treatment should be based on MG subgroup and includes symptomatic treatment using acetylcholinesterase inhibitors, thymectomy and immunotherapy. Intravenous immunoglobulin and plasma exchange are fast-acting treatments used for disease exacerbations, and intensive care is necessary during exacerbations with respiratory failure. Comorbidity is frequent, particularly in elderly patients. Active physical training should be encouraged.
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Wang Z, Yan Y. Immunopathogenesis in Myasthenia Gravis and Neuromyelitis Optica. Front Immunol 2017; 8:1785. [PMID: 29312313 PMCID: PMC5732908 DOI: 10.3389/fimmu.2017.01785] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 11/29/2017] [Indexed: 12/13/2022] Open
Abstract
Myasthenia gravis (MG) and neuromyelitis optica (NMO) are autoimmune channelopathies of the peripheral neuromuscular junction (NMJ) and central nervous system (CNS) that are mainly mediated by humoral immunity against the acetylcholine receptor (AChR) and aquaporin-4 (AQP4), respectively. The diseases share some common features, including genetic predispositions, environmental factors, the breakdown of tolerance, the collaboration of T cells and B cells, imbalances in T helper 1 (Th1)/Th2/Th17/regulatory T cells, aberrant cytokine and antibody secretion, and complement system activation. However, some aspects of the immune mechanisms are unique. Both targets (AChR and AQP4) are expressed in the periphery and CNS, but MG mainly affects the NMJ in the periphery outside of CNS, whereas NMO preferentially involves the CNS. Inflammatory cells, including B cells and macrophages, often infiltrate the thymus but not the target—muscle in MG, whereas the infiltration of inflammatory cells, mainly polymorphonuclear leukocytes and macrophages, in NMO, is always observed in the target organ—the spinal cord. A review of the common and discrepant characteristics of these two autoimmune channelopathies may expand our understanding of the pathogenic mechanism of both disorders and assist in the development of proper treatments in the future.
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Affiliation(s)
- Zhen Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.,Tianjin Medical University General Hospital, Tianjin Neurological Institute, Tianjin, China
| | - Yaping Yan
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, College of Life Sciences, Shaanxi Normal University, Xi'an, China
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15
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Liu FC, Kuo CF, See LC, Tsai HI, Yu HP. Familial aggregation of myasthenia gravis in affected families: a population-based study. Clin Epidemiol 2017; 9:527-535. [PMID: 29138598 PMCID: PMC5679568 DOI: 10.2147/clep.s146617] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
Introduction Myasthenia gravis (MG) is clinically heterogeneous and can be life-threatening if bulbar or respiratory muscles are involved. However, relative contributions of genetic, shared, and nonshared environmental factors to MG susceptibility remain unclear. The aim of this study was to examine the familial aggregation and heritability of MG and the relative risks (RRs) of other autoimmune diseases in the relatives of patients with MG. Methods A population-based family study using the Taiwan National Health Insurance (NHI) Database was conducted. Participants included all individuals (N=23,422,955) who were actively registered in the NHI Database in 2013, 15,066 of whom had at least one first-degree relative with MG. We identified 8,638 parent–child relationships, 3,279 with an affected offspring, 3,134 with affected siblings, and 26 with affected twins. Prevalence and RRs of MG and other autoimmune diseases in the relatives of patients as well as the relative contributions of heritability, shared, and nonshared environmental factors to MG susceptibility were measured. Results RRs (95% confidence intervals [CIs]) for MG were 17.85 (8.71–36.56) for patients’ siblings, 5.33 (2.79–10.18) for parents, 5.82 (3.03–11.16) for offspring, and 1.42 (0.20–10.10) for spouses without genetic similarities. RRs (95% CIs) in individuals with a first-degree relative with MG were 2.18 (1.53–3.12) for systemic lupus erythematosus, 1.73 (1.09–2.74) for primary Sjögren’s syndrome, 1.90 (1.66–2.18) for autoimmune thyroid disease, and 1.68 (1.22–2.30) for rheumatoid arthritis. Accountability for the phenotypic variance of MG was 82.1% for familial transmission and 17.9% for nonshared environmental factors. Conclusion Individual risks of MG and other autoimmune diseases are increased in the relatives of patients with MG. Familial transmission of MG was estimated to be 82.1%.
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Affiliation(s)
- Fu-Chao Liu
- Department of Anesthesiology, Chang Gung Memorial Hospital.,College of Medicine, Chang Gung University
| | - Chang-Fu Kuo
- College of Medicine, Chang Gung University.,Division of Rheumatology, Allergy and Immunology, Chang Gung Memorial Hospital.,Department of Public Health, College of Medicine, Chang Gung University.,Office for Big Data Research, Chang Gung Memorial Hospital
| | - Lai-Chu See
- Department of Public Health, College of Medicine, Chang Gung University.,Biostatistics Core Laboratory, Molecular Medicine Research Center
| | - Hsin-I Tsai
- Department of Anesthesiology, Chang Gung Memorial Hospital.,College of Medicine, Chang Gung University.,Graduate Institute of Clinical Medical Sciences, Chang Gung University, Taoyuan, Taiwan, Republic of China
| | - Huang-Ping Yu
- Department of Anesthesiology, Chang Gung Memorial Hospital.,College of Medicine, Chang Gung University
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Yi JS, Guptill JT, Stathopoulos P, Nowak RJ, O'Connor KC. B cells in the pathophysiology of myasthenia gravis. Muscle Nerve 2017; 57:172-184. [PMID: 28940642 DOI: 10.1002/mus.25973] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/07/2017] [Indexed: 12/21/2022]
Abstract
Myasthenia gravis (MG) is an archetypal autoimmune disease. The pathology is characterized by autoantibodies to the acetylcholine receptor (AChR) in most patients or to muscle-specific tyrosine kinase (MuSK) in others and to a growing number of other postsynaptic proteins in smaller subsets. A decrease in the number of functional AChRs or functional interruption of the AChR within the muscle end plate of the neuromuscular junction is caused by pathogenic autoantibodies. Although the molecular immunology underpinning the pathology is well understood, much remains to be learned about the cellular immunology contributing to the production of autoantibodies. This Review documents research concerning the immunopathology of MG, bringing together evidence principally from human studies with an emphasis on the role of adaptive immunity and B cells in particular. Proposed mechanisms for autoimmunity, which take into account that different types of MG may incorporate divergent immunopathology, are offered. Muscle Nerve 57: 172-184, 2018.
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Affiliation(s)
- John S Yi
- Division of Surgical Sciences, Department of Surgery, Duke University Medical Center, Durham, North Carolina, USA
| | - Jeffrey T Guptill
- Department of Neurology, Neuromuscular Section, Duke University Medical Center, Durham, North Carolina, USA
| | - Panos Stathopoulos
- Department of Neurology, Yale School of Medicine, Room 353J, 300 George Street, New Haven, Connecticut, 06511, USA
| | - Richard J Nowak
- Department of Neurology, Yale School of Medicine, Room 353J, 300 George Street, New Haven, Connecticut, 06511, USA
| | - Kevin C O'Connor
- Department of Neurology, Yale School of Medicine, Room 353J, 300 George Street, New Haven, Connecticut, 06511, USA
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Mamrut S, Avidan N, Truffault F, Staun-Ram E, Sharshar T, Eymard B, Frenkian M, Pitha J, de Baets M, Servais L, Berrih-Aknin S, Miller A. Methylome and transcriptome profiling in Myasthenia Gravis monozygotic twins. J Autoimmun 2017; 82:62-73. [PMID: 28549776 DOI: 10.1016/j.jaut.2017.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2017] [Revised: 05/11/2017] [Accepted: 05/15/2017] [Indexed: 01/07/2023]
Abstract
OBJECTIVE To identify novel genetic and epigenetic factors associated with Myasthenia gravis (MG) using an identical twins experimental study design. METHODS The transcriptome and methylome of peripheral monocytes were compared between monozygotic (MZ) twins discordant and concordant for MG, as well as with MG singletons and healthy controls, all females. Sets of differentially expressed genes and differentially methylated CpGs were validated using RT-PCR for expression and target bisulfite sequencing for methylation on additional samples. RESULTS >100 differentially expressed genes and ∼1800 differentially methylated CpGs were detected in peripheral monocytes between MG patients and controls. Several transcripts associated with immune homeostasis and inflammation resolution were reduced in MG patients. Only a relatively few genes differed between the discordant healthy and MG co-twins, and both their expression and methylation profiles demonstrated very high similarity. INTERPRETATION This is the first study to characterize the DNA methylation profile in MG, and the expression profile of immune cells in MZ twins with MG. Results suggest that numerous small changes in gene expression or methylation might together contribute to disease. Impaired monocyte function in MG and decreased expression of genes associated with inflammation resolution could contribute to the chronicity of the disease. Findings may serve as potential new predictive biomarkers for disease and disease activity, as well as potential future targets for therapy development. The high similarity between the healthy and the MG discordant twins, suggests that a molecular signature might precede a clinical phenotype, and that genetic predisposition may have a stronger contribution to disease than previously assumed.
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Affiliation(s)
- Shimrat Mamrut
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel
| | - Nili Avidan
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel
| | - Frédérique Truffault
- INSERM - U974/CNRS UMR7215//UPMC UM76/AIM, Institute of Myology Pitie-Salpetriere, Paris, 73013, France
| | - Elsebeth Staun-Ram
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel
| | - Tarek Sharshar
- General Intensive Care Medicine, Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, University of Versailles Saint-Quentin en Yvelines, 92380, Garches, France
| | - Bruno Eymard
- Department of Neuromuscular Disorders, CHU Salpêtrière, Paris, 75013, France
| | - Mélinée Frenkian
- INSERM - U974/CNRS UMR7215//UPMC UM76/AIM, Institute of Myology Pitie-Salpetriere, Paris, 73013, France
| | - Jiri Pitha
- Department of Neurology and Clinical Neuroscience Center, 1st Faculty of Medicine, Charles University and General Teaching Hospital, Prague, Czech Republic
| | - Marc de Baets
- Neuroimmunology Group, Division of Neuroscience, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Laurent Servais
- Institute of Myology, Groupe hospitalier Pitié-Salpêtrière, AP-HP, Sorbonne Universités, UPMC Universités Paris 06, INSERM, Paris, 75013, France
| | - Sonia Berrih-Aknin
- INSERM - U974/CNRS UMR7215//UPMC UM76/AIM, Institute of Myology Pitie-Salpetriere, Paris, 73013, France
| | - Ariel Miller
- Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, 31096, Israel; Division of Neuroimmunology, Lady Davis Carmel Medical Center, Haifa, 34362, Israel.
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18
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Association of early onset myasthenia gravis in Newfoundland dogs with the canine major histocompatibility complex class I. Neuromuscul Disord 2017; 27:409-416. [DOI: 10.1016/j.nmd.2017.01.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2016] [Revised: 01/08/2017] [Accepted: 01/27/2017] [Indexed: 12/19/2022]
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19
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Verschuuren J, Strijbos E, Vincent A. Neuromuscular junction disorders. HANDBOOK OF CLINICAL NEUROLOGY 2017; 133:447-66. [PMID: 27112691 DOI: 10.1016/b978-0-444-63432-0.00024-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Diseases of the neuromuscular junction comprise a wide range of disorders. Antibodies, genetic mutations, specific drugs or toxins interfere with the number or function of one of the essential proteins that control signaling between the presynaptic nerve ending and the postsynaptic muscle membrane. Acquired autoimmune disorders of the neuromuscular junction are the most common and are described here. In myasthenia gravis, antibodies to acetylcholine receptors or to proteins involved in receptor clustering, particularly muscle-specific kinase, cause direct loss of acetylcholine receptors or interfere with the agrin-induced acetylcholine receptor clustering necessary for efficient neurotransmission. In the Lambert-Eaton myasthenic syndrome (LEMS), loss of the presynaptic voltage-gated calcium channels results in reduced release of the acetylcholine transmitter. The conditions are generally recognizable clinically and the diagnosis confirmed by serologic testing and electromyography. Screening for thymomas in myasthenia or small cell cancer in LEMS is important. Fortunately, a wide range of symptomatic treatments, immunosuppressive drugs, or other immunomodulating therapies is available. Future research is directed to understanding the pathogenesis, discovering new antigens, and trying to develop disease-specific treatments.
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Affiliation(s)
- Jan Verschuuren
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands.
| | - Ellen Strijbos
- Department of Neurology, Leiden University Medical Centre, Leiden, The Netherlands
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, Oxford, UK
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20
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Boldingh MI, Maniaol A, Brunborg C, Dekker L, Lipka A, Niks EH, Verschuuren J, Tallaksen C. Prevalence and clinical aspects of immigrants with myasthenia gravis in northern Europe. Muscle Nerve 2017; 55:819-827. [PMID: 27641227 DOI: 10.1002/mus.25408] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2016] [Revised: 09/07/2016] [Accepted: 09/14/2016] [Indexed: 01/22/2023]
Abstract
INTRODUCTION Multiethnic studies can provide etiological clues toward the genetic and environmental influence of a disease. The aim of this study was to determine prevalence and clinical features of myasthenia gravis (MG) in immigrants compared with native patients in 2 population-based cohorts. METHODS This cross-sectional study included 843 MG patients (375 from Norway and 468 from the Netherlands). Ethnic background was defined by questionnaires. RESULTS Among the participating MG patients, 163 of 843 (19.3%) were first or second generation immigrants, mainly from Europe, Asia, and South America. No marked prevalence differences were found between immigrants and native ethnic groups. MG with muscle specific kinase antibodies and MG with thymoma were more frequent in Asian MG immigrants compared with other ethnic groups (8% vs. 0-4%; P < 0.001 and 21% vs. 6-10%; P < 0.001), respectively. CONCLUSIONS Our findings indicate that Asian immigrant MG patients carry genetic factors or environmental/lifestyle factors which contribute to their specific phenotype, even after migration. Muscle Nerve 55: 819-827, 2017.
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Affiliation(s)
- Marion Ingeborg Boldingh
- Department of Neurology, Oslo University Hospital, pb 4950, Nydalen, 0424, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
| | - Angelina Maniaol
- Department of Neurology, Oslo University Hospital, pb 4950, Nydalen, 0424, Oslo, Norway
| | - Cathrine Brunborg
- Department of Neurology, Oslo University Hospital, pb 4950, Nydalen, 0424, Oslo, Norway.,Oslo Centre for Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, Oslo, Norway
| | - Luuk Dekker
- Department of Neurology, Leiden University Medical Centre, The Netherlands
| | - Alexander Lipka
- Department of Neurology, Leiden University Medical Centre, The Netherlands
| | - Erik Harmen Niks
- Department of Neurology, Leiden University Medical Centre, The Netherlands
| | - Jan Verschuuren
- Department of Neurology, Leiden University Medical Centre, The Netherlands
| | - Chantal Tallaksen
- Department of Neurology, Oslo University Hospital, pb 4950, Nydalen, 0424, Oslo, Norway.,Institute of Clinical Medicine, University of Oslo, Oslo, Norway
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Karni A, Asmail A, Drory VE, Kolb H, Kesler A. Thymus involvement in myasthenia gravis: Epidemiological and clinical impacts of different self-tolerance breakdown mechanisms. J Neuroimmunol 2016; 298:58-62. [DOI: 10.1016/j.jneuroim.2016.07.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Revised: 07/02/2016] [Accepted: 07/06/2016] [Indexed: 01/24/2023]
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22
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Fang F, Sveinsson O, Thormar G, Granqvist M, Askling J, Lundberg IE, Ye W, Hammarström L, Pirskanen R, Piehl F. The autoimmune spectrum of myasthenia gravis: a Swedish population-based study. J Intern Med 2015; 277:594-604. [PMID: 25251578 DOI: 10.1111/joim.12310] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
OBJECTIVES To determine the prevalence of myasthenia gravis (MG) and the rate of concurrent autoimmune diseases in patients with MG. DESIGN AND SETTING Using the Swedish health and population registers, during the period 2005-2010, we conducted a nested case-control study of patients with MG (n = 2045) with five age- and sex-matched population-based controls per case. Register-based MG diagnosis was validated against the Stockholm MG Cohort. Similar nested case-control studies were conducted in patients with multiple sclerosis (MS), as a neuroinflammatory disease control, and siblings of patients with MG. MAIN OUTCOME MEASURE Odds ratios (ORs) and their 95% confidence intervals (CIs) were calculated as a measure of the association between MG and other autoimmune diseases. RESULTS The prevalence of MG was 24.8/100,000, and patients with MG had an increased risk of another autoimmune disease compared to controls (22.0% vs. 8.9%; OR: 2.82, 95% CI: 2.49-3.20); this risk was stronger amongst younger persons and women. Polymyositis/dermatomyositis, systemic lupus erythematosus and Addison's disease, three conditions regulated by the HLA-B8-DR3 haplotype, were most strongly associated with MG, especially early-onset disease. HLA typing in the Stockholm MG Cohort showed that early-onset MG was indeed dominated by HLA-B8-DR3. The risk of another autoimmune disease was increased in both patients with MS and siblings of patients with MG, compared to their respective controls, but to a lesser extent than in patients with MG. CONCLUSIONS Our results suggest that MG shares risk factors with other autoimmune diseases, to a greater degree than MS, with a particular role of the HLA-B8-DR3 haplotype, especially amongst younger and female patients.
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Affiliation(s)
- F Fang
- Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Stockholm, Sweden
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Varela M, García-Camba P, Gutiérrez Mosquera B, García Rosas S, Lorda I. Desarrollo tardío de múltiples dientes supernumerarios en una paciente con miastenia gravis juvenil tratada con azatioprina. An Pediatr (Barc) 2014; 81:200-1. [DOI: 10.1016/j.anpedi.2013.10.053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2013] [Accepted: 10/31/2013] [Indexed: 10/25/2022] Open
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24
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Genetic basis of myasthenia gravis – A comprehensive review. J Autoimmun 2014; 52:146-53. [DOI: 10.1016/j.jaut.2013.12.001] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2013] [Accepted: 12/02/2013] [Indexed: 11/24/2022]
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25
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Berrih-Aknin S. Myasthenia Gravis: paradox versus paradigm in autoimmunity. J Autoimmun 2014; 52:1-28. [PMID: 24934596 DOI: 10.1016/j.jaut.2014.05.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 05/07/2014] [Indexed: 12/12/2022]
Abstract
Myasthenia Gravis (MG) is a paradigm of organ-specific autoimmune disease (AID). It is mediated by antibodies that target the neuromuscular junction. The purpose of this review is to place MG in the general context of autoimmunity, to summarize the common mechanisms between MG and other AIDs, and to describe the specific mechanisms of MG. We have chosen the most common organ-specific AIDs to compare with MG: type 1 diabetes mellitus (T1DM), autoimmune thyroid diseases (AITD), multiple sclerosis (MS), some systemic AIDs (systemic lupus erythematous (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS)), as well as inflammatory diseases of the gut and liver (celiac disease (CeD), Crohn's disease (CD), and primary biliary cirrhosis (PBC)). Several features are similar between all AIDs, suggesting that common pathogenic mechanisms lead to their development. In this review, we address the predisposing factors (genetic, epigenetic, hormones, vitamin D, microbiota), the triggering components (infections, drugs) and their interactions with the immune system [1,2]. The dysregulation of the immune system is detailed and includes the role of B cells, Treg cells, Th17 and cytokines. We particularly focused on the role of TNF-α and interferon type I whose role in MG is very analogous to that in several other AIDS. The implication of AIRE, a key factor in central tolerance is also discussed. Finally, if MG is a prototype of AIDS, it has a clear specificity compared to the other AIDS, by the fact that the target organ, the muscle, is not the site of immune infiltration and B cell expansion, but exclusively that of antibody-mediated pathogenic mechanisms. By contrast, the thymus in the early onset subtype frequently undergoes tissue remodeling, resulting in the development of ectopic germinal centers surrounded by high endothelial venules (HEV), as observed in the target organs of many other AIDs.
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Affiliation(s)
- Sonia Berrih-Aknin
- Sorbonne Universités, UPMC Univ Paris 06, Myology Research Center UM76, F-75013 Paris, France; INSERM U974, F-75013 Paris, France; CNRS FRE 3617, F-75013 Paris, France; Institute of Myology, F-75013 Paris, France.
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Avidan N, Le Panse R, Harbo HF, Bernasconi P, Poulas K, Ginzburg E, Cavalcante P, Colleoni L, Baggi F, Antozzi C, Truffault F, Horn-Saban S, Pöschel S, Zagoriti Z, Maniaol A, Lie BA, Bernard I, Saoudi A, Illes Z, Casasnovas Pons C, Melms A, Tzartos S, Willcox N, Kostera-Pruszczyk A, Tallaksen C, Mantegazza R, Berrih-Aknin S, Miller A. VAV1 and BAFF, via NFκB pathway, are genetic risk factors for myasthenia gravis. Ann Clin Transl Neurol 2014; 1:329-39. [PMID: 25356403 PMCID: PMC4184684 DOI: 10.1002/acn3.51] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2014] [Accepted: 02/12/2014] [Indexed: 01/22/2023] Open
Abstract
Objective To identify novel genetic loci that predispose to early-onset myasthenia gravis (EOMG) applying a two-stage association study, exploration, and replication strategy. Methods Thirty-four loci and one confirmation loci, human leukocyte antigen (HLA)-DRA, were selected as candidate genes by team members of groups involved in different research aspects of MG. In the exploration step, these candidate genes were genotyped in 384 EOMG and 384 matched controls and significant difference in allele frequency were found in eight genes. In the replication step, eight candidate genes and one confirmation loci were genotyped in 1177 EOMG patients and 814 controls, from nine European centres. Results Allele frequency differences were found in four novel loci: CD86, AKAP12, VAV1, B-cell activating factor (BAFF), and tumor necrosis factor-alpha (TNF-α), and these differences were consistent in all nine cohorts. Haplotype trend test supported the differences in allele frequencies between cases and controls. In addition, allele frequency difference in female versus male patients at HLA-DRA and TNF-α loci were observed. Interpretation The genetic associations to EOMG outside the HLA complex are novel and of interest as VAV1 is a key signal transducer essential for T- and B-cell activation, and BAFF is a cytokine that plays important roles in the proliferation and differentiation of B-cells. Moreover, we noted striking epistasis between the predisposing VAV1 and BAFF haplotypes; they conferred a greater risk in combination than alone. These, and CD86, share the same signaling pathway, namely nuclear factor-kappaB (NFκB), thus implicating dysregulation of proinflammatory signaling in predisposition to EOMG.
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Affiliation(s)
- Nili Avidan
- Pharmacogenetics and Translational Genetics Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology Haifa, Israel
| | - Rozen Le Panse
- Research Unit (INSERM U974/CNRS UMR7215//UPMC UM76/AIM) - Institute of Myology Pitié-Salpêtrière Paris, France
| | - Hanne F Harbo
- Department of Neurology, Oslo University Hospital Ullevål, Norway ; Institute of Clinical Medicine, University of Oslo Oslo, Norway
| | - Pia Bernasconi
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | | | - Elizabeta Ginzburg
- Pharmacogenetics and Translational Genetics Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology Haifa, Israel
| | - Paola Cavalcante
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | - Lara Colleoni
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | - Fulvio Baggi
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | - Carlo Antozzi
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | - Frédérique Truffault
- Research Unit (INSERM U974/CNRS UMR7215//UPMC UM76/AIM) - Institute of Myology Pitié-Salpêtrière Paris, France
| | - Shirley Horn-Saban
- Department of Biological Services, Weizmann Institute of Science Rehovot, Israel
| | - Simone Pöschel
- Department of Neurology, Tübingen University Medical Center Tubingen, Germany ; Neurologische Klinik, Universitätsklinikum Erlangen Erlangen, Germany
| | - Zoi Zagoriti
- Department of Pharmacy, University of Patras Patras, Greece
| | - Angelina Maniaol
- Department of Neurology, Oslo University Hospital Ullevål, Norway
| | - Benedicte A Lie
- Institute of Clinical Medicine, University of Oslo Oslo, Norway ; Department of Medical Genetics, Oslo University Hospital Ullevål, Norway
| | - Isabelle Bernard
- INSERM, U1043 Toulouse, F-31300, France ; Centre National de la Recherche Scientifique, U5282 Toulouse, F-31300, France
| | - Abdelhadi Saoudi
- INSERM, U1043 Toulouse, F-31300, France ; Centre National de la Recherche Scientifique, U5282 Toulouse, F-31300, France
| | - Zsolt Illes
- Department of Neurology, University of Pecs Pecs, Hungary ; Department of Neurology, Odense University Hospital, University of Southern Denmark Odense, Denmark
| | | | - Arthur Melms
- Department of Neurology, Tübingen University Medical Center Tubingen, Germany ; Neurologische Klinik, Universitätsklinikum Erlangen Erlangen, Germany
| | - Socrates Tzartos
- Department of Pharmacy, University of Patras Patras, Greece ; Hellenic Pasteur Institute Athens, Greece
| | - Nicholas Willcox
- Clinical Neurology, Weatherall Institute for Molecular Medicine, University of Oxford Oxford, United Kingdom
| | | | - Chantal Tallaksen
- Department of Neurology, Oslo University Hospital Ullevål, Norway ; Institute of Clinical Medicine, University of Oslo Oslo, Norway
| | - Renato Mantegazza
- Department of Neurology IV, Neuromuscular Diseases and Neuroimmunology, Fondazione Istituto Neurologico Carlo Besta (INNCB) Milan, Italy
| | - Sonia Berrih-Aknin
- Research Unit (INSERM U974/CNRS UMR7215//UPMC UM76/AIM) - Institute of Myology Pitié-Salpêtrière Paris, France
| | - Ariel Miller
- Pharmacogenetics and Translational Genetics Center, The Rappaport Faculty of Medicine and Research Institute, Technion-Israel Institute of Technology Haifa, Israel ; Division of Neuroimmunology, Carmel Medical Center Haifa, Israel
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Berrih-Aknin S, Le Panse R. Myasthenia gravis: a comprehensive review of immune dysregulation and etiological mechanisms. J Autoimmun 2014; 52:90-100. [PMID: 24389034 DOI: 10.1016/j.jaut.2013.12.011] [Citation(s) in RCA: 224] [Impact Index Per Article: 22.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2013] [Accepted: 12/12/2013] [Indexed: 12/31/2022]
Abstract
Autoimmune myasthenia gravis (MG) is characterized by muscle weakness caused by antibodies directed against proteins of the neuromuscular junction. The main antigenic target is the acetylcholine receptor (AChR), but the muscle Specific Kinase (MuSK) and the low-density lipoprotein receptor-related protein (LRP4) are also targets. This review summarizes the clinical and biological data available for different subgroups of patients, who are classified according to antigenic target, age of onset, and observed thymic abnormalities, such as follicular hyperplasia or thymoma. Here, we analyze in detail the role of the thymus in the physiopathology of MG and propose an explanation for the development of the thymic follicular hyperplasia that is commonly observed in young female patients with anti-AChR antibodies. The influence of the pro-inflammatory environment is discussed, particularly the role of TNF-α and Th17-related cytokines, which could explain the escape of thymic T cells from regulation and the chronic inflammation in the MG thymus. Together with this immune dysregulation, active angiogenic processes and the upregulation of chemokines could promote thymic follicular hyperplasia. MG is a multifactorial disease, and we review the etiological mechanisms that could lead to its onset. Recent global genetic analyses have highlighted potential susceptibility genes. In addition, miRNAs, which play a crucial role in immune function, have been implicated in MG by recent studies. We also discuss the role of sex hormones and the influence of environmental factors, such as the viral hypothesis. This hypothesis is supported by reports that type I interferon and molecules mimicking viral infection can induce thymic changes similar to those observed in MG patients with anti-AChR antibodies.
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Affiliation(s)
- Sonia Berrih-Aknin
- INSERM U974, Paris, France; CNRS UMR 7215, Paris, France; UPMC Univ Paris 6, Paris, France; AIM, Institute of myology, Paris, France.
| | - Rozen Le Panse
- INSERM U974, Paris, France; CNRS UMR 7215, Paris, France; UPMC Univ Paris 6, Paris, France; AIM, Institute of myology, Paris, France.
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Berrih-Aknin S, Le Panse R. [Myasthenia gravis and autoantibodies: Pathophysiology of the different subtypes]. Rev Med Interne 2013; 35:413-20. [PMID: 24156976 DOI: 10.1016/j.revmed.2013.09.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2013] [Accepted: 09/23/2013] [Indexed: 10/26/2022]
Abstract
Myasthenia gravis is characterized by muscle weakness and abnormal fatigability. It is an autoimmune disease caused by the presence of antibodies against components of the muscle membrane localized at the neuromuscular junction. In most cases, the autoantibodies are directed against the acetylcholine receptor (AChR). Recently, other targets have been described, such as muscle-specific kinase protein (MuSK) or lipoprotein related protein 4 (LRP4). The origin of the autoimmune response is not known, but thymic abnormalities and defects in immune regulation certainly play a major role in patients with anti-AChR antibodies. Genetic predisposition probably influences the occurrence of the disease. Sex hormones seem to play a role in the early form of the disease. Muscle weakness is fluctuating and worsens with exercise. Myasthenia gravis could be classified according to the location of the affected muscles (ocular versus generalized), the age of onset of symptoms, thymic abnormalities and profile of autoantibodies. These criteria are used to optimize the management and treatment of patients. In this review, we analyze the latest concepts of the pathophysiology of myasthenia gravis according to the different subgroups of the disease, including a description of the role of immunological, genetic and environmental factors. The potential viral hypothesis of this disease is discussed. Finally, we also discuss the biological assays available to validate the diagnosis.
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Affiliation(s)
- S Berrih-Aknin
- Unité mixte de recherche (UMR), CNRS UMR7215/Inserm U974/UPMC UM76/AIM, thérapie des maladies du muscle strié, groupe hospitalier Pitié-Salpêtrière, 105, boulevard de l'Hôpital, 75651 Paris cedex 13, France.
| | - R Le Panse
- Unité mixte de recherche (UMR), CNRS UMR7215/Inserm U974/UPMC UM76/AIM, thérapie des maladies du muscle strié, groupe hospitalier Pitié-Salpêtrière, 105, boulevard de l'Hôpital, 75651 Paris cedex 13, France
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29
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Ramanujam R, Ramanujam S, Hillert J. Considerations for subgroups and phenocopies in complex disease genetics. PLoS One 2013; 8:e71614. [PMID: 23977088 PMCID: PMC3748062 DOI: 10.1371/journal.pone.0071614] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 06/30/2013] [Indexed: 02/05/2023] Open
Abstract
The number of identified genetic variants associated to complex disease cannot fully explain heritability. This may be partially due to more complicated patterns of predisposition than previously suspected. Diseases such as multiple sclerosis (MS) may consist of multiple disease causing mechanisms, each comprised of several elements. We describe how the effect of subgroups can be calculated using the standard association measurement odds ratio, which is then manipulated to provide a formula for the true underlying association present within the subgroup. This is sensitive to the initial minor allele frequencies present in both cases and the subgroup of patients. The methodology is then extended to the χ2 statistic, for two related scenarios. First, to determine the true χ2 when phenocopies or disease subtypes reduce association and are reclassified as controls when calculating statistics. Here, the χ2 is given by, or for equal numbers of cases and controls. Second, when subgroups corresponding to heterogeneity mask the true effect size, but no reclassification is made. Here, the proportion increase in total sample size required to attain the same χ2 statistic as the subgroup is given as , and a python script to calculate and plot this value is provided at kirc.se. Practical examples show how in a study of modest size (1000 cases and 1000 controls), a non-significant SNP may exceed genome-wide significance when corresponding to a subgroup of 20% of cases, and may occur in heterozygous form in all cases. This methodology may explain the modest association found in diseases such as MS wherein heterogeneity confounds straightforward measurement of association.
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Affiliation(s)
- Ryan Ramanujam
- Department of Clinical Neuroscience, Karolinska Institutet at Karolinska University Hospital Solna, Stockholm, Sweden
- * E-mail:
| | - S. Ramanujam
- The Peter J. Tobin College of Business, St. John’s University, New York, New York, United States of America
| | - Jan Hillert
- Department of Clinical Neuroscience, Karolinska Institutet at Karolinska University Hospital Solna, Stockholm, Sweden
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30
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Verschuuren JJ, Huijbers MG, Plomp JJ, Niks EH, Molenaar PC, Martinez-Martinez P, Gomez AM, De Baets MH, Losen M. Pathophysiology of myasthenia gravis with antibodies to the acetylcholine receptor, muscle-specific kinase and low-density lipoprotein receptor-related protein 4. Autoimmun Rev 2013; 12:918-23. [DOI: 10.1016/j.autrev.2013.03.001] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2013] [Indexed: 01/13/2023]
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31
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Greer JM, McCombe PA. The role of epigenetic mechanisms and processes in autoimmune disorders. Biologics 2012; 6:307-27. [PMID: 23055689 PMCID: PMC3459549 DOI: 10.2147/btt.s24067] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Indexed: 12/18/2022]
Abstract
The lack of complete concordance of autoimmune disease in identical twins suggests that nongenetic factors play a major role in determining disease susceptibility. In this review, we consider how epigenetic mechanisms could affect the immune system and effector mechanisms in autoimmunity and/or the target organ of autoimmunity and thus affect the development of autoimmune diseases. We also consider the types of stimuli that lead to epigenetic modifications and how these relate to the epidemiology of autoimmune diseases and the biological pathways operative in different autoimmune diseases. Increasing our knowledge of these epigenetic mechanisms and processes will increase the prospects for controlling or preventing autoimmune diseases in the future through the use of drugs that target the epigenetic pathways.
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Affiliation(s)
- Judith M Greer
- The University of Queensland, UQ Centre for Clinical Research, Brisbane, Queensland, Australia
| | - Pamela A McCombe
- The University of Queensland, UQ Centre for Clinical Research, Brisbane, Queensland, Australia
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32
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Sex differences and genomics in autoimmune diseases. J Autoimmun 2012; 38:J254-65. [DOI: 10.1016/j.jaut.2011.12.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2011] [Accepted: 12/02/2011] [Indexed: 12/23/2022]
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33
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Bogdanos DP, Smyk DS, Rigopoulou EI, Mytilinaiou MG, Heneghan MA, Selmi C, Gershwin ME. Twin studies in autoimmune disease: genetics, gender and environment. J Autoimmun 2011; 38:J156-69. [PMID: 22177232 DOI: 10.1016/j.jaut.2011.11.003] [Citation(s) in RCA: 194] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2011] [Accepted: 11/12/2011] [Indexed: 02/08/2023]
Abstract
Twin studies are powerful tools to discriminate whether a complex disease is due to genetic or environmental factors. High concordance rates among monozygotic (MZ) twins support genetic factors being predominantly involved, whilst low rates are suggestive of environmental factors. Twin studies have often been utilised in the study of systemic and organ specific autoimmune diseases. As an example, type I diabetes mellitus has been investigated to establish that that disease is largely affected by genetic factors, compared to rheumatoid arthritis or scleroderma, which have a weaker genetic association. However, large twin studies are scarce or virtually non-existent in other autoimmune diseases which have been limited to few sets of twins and individual case reports. In addition to the study of the genetic and environmental contributions to disease, it is likely that twin studies will also provide data in regards to the clinical course of disease, as well as risk for development in related individuals. More importantly, genome-wide association studies have thus far reported genomic variants that only account for a minority of autoimmunity cases, and cannot explain disease discordance in MZ twins. Future research is therefore encouraged not only in the analysis of twins with autoimmune disease, but also in regards to epigenetic factors or rare variants that may be discovered with next-generation sequencing. This review will examine the literature surrounding twin studies in autoimmune disease including discussions of genetics and gender.
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Affiliation(s)
- Dimitrios P Bogdanos
- Institute of Liver Studies, Liver Immunopathology, King's College London School of Medicine at King's College Hospital, London, UK.
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34
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Wang N, Shen N, Vyse TJ, Anand V, Gunnarson I, Sturfelt G, Rantapää-Dahlqvist S, Elvin K, Truedsson L, Andersson BA, Dahle C, Örtqvist E, Gregersen PK, Behrens TW, Hammarström L. Selective IgA deficiency in autoimmune diseases. Mol Med 2011; 17:1383-96. [PMID: 21826374 PMCID: PMC3321806 DOI: 10.2119/molmed.2011.00195] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2011] [Accepted: 08/02/2011] [Indexed: 12/12/2022] Open
Abstract
Selective immunoglobulin A deficiency (IgAD) is the most common primary immunodeficiency in Caucasians. It has previously been suggested to be associated with a variety of concomitant autoimmune diseases. In this review, we present data on the prevalence of IgAD in patients with Graves disease (GD), systemic lupus erythematosus (SLE), type 1 diabetes (T1D), celiac disease (CD), myasthenia gravis (MG) and rheumatoid arthritis (RA) on the basis of both our own recent large-scale screening results and literature data. Genetic factors are important for the development of both IgAD and various autoimmune disorders, including GD, SLE, T1D, CD, MG and RA, and a strong association with the major histocompatibility complex (MHC) region has been reported. In addition, non-MHC genes, such as interferon-induced helicase 1 (IFIH1) and c-type lectin domain family 16, member A (CLEC16A), are also associated with the development of IgAD and some of the above diseases. This indicates a possible common genetic background. In this review, we present suggestive evidence for a shared genetic predisposition between these disorders.
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Affiliation(s)
- Ning Wang
- Division of Clinical Immunology, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Nan Shen
- Department of Rheumatology, Renji Hospital, JiaoTong University School of Medicine, Shanghai, China
| | - Timothy J Vyse
- Section of Molecular Genetics and Rheumatology, Hammersmith Hospital, London, United Kingdom
| | - Vidya Anand
- Section of Molecular Genetics and Rheumatology, Hammersmith Hospital, London, United Kingdom
| | - Iva Gunnarson
- Rheumatology Unit, Department of Medicine, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Gunnar Sturfelt
- Department of Rheumatology, Lund University Hospital, Lund, Sweden
| | | | - Kerstin Elvin
- Unit of Clinical Immunology, Department of Clinical Immunology and Transfusion Medicine, Karolinska University Hospital Huddinge, Stockholm, Sweden
| | - Lennart Truedsson
- Department of Laboratory Medicine, Section of Microbiology, Immunology and Glycobiology, Lund University, Sweden
| | | | - Charlotte Dahle
- Clinical Immunology Unit, Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Eva Örtqvist
- Department of Woman and Child Health, Astrid Lindgren Children’s Hospital, Karolinska University Hospital Solna, Stockholm, Sweden
| | - Peter K Gregersen
- Robert S. Boas Center for Genomics and Human Genetics, Feinstein Institute for Medical Research, Manhasset, New York, United States of America
| | - Timothy W Behrens
- Division of Immunology, Tissue Growth & Repair, Biomarker Discovery and Human Genetics, Genentech, South San Francisco, California, United States of America
| | - Lennart Hammarström
- Division of Clinical Immunology, Department of Laboratory Medicine, Karolinska Institutet at Karolinska University Hospital Huddinge, Stockholm, Sweden
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