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Sun S, Shen Y, Zhang X, Ding N, Xu Z, Zhang Q, Li L. The MuSK agonist antibody protects the neuromuscular junction and extends the lifespan in C9orf72-ALS mice. Mol Ther 2024; 32:2176-2189. [PMID: 38734896 DOI: 10.1016/j.ymthe.2024.05.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 04/06/2024] [Accepted: 05/09/2024] [Indexed: 05/13/2024] Open
Abstract
The disassembly of the neuromuscular junction (NMJ) is an early event in amyotrophic lateral sclerosis (ALS), ultimately leading to motor dysfunction and lethal respiratory paralysis. The hexanucleotide GGGGCC repeat expansion in the C9orf72 gene is the most common genetic mutation, and the dipeptide repeat (DPR) proteins have been shown to cause neurodegeneration. While no drugs can treat ALS patients efficiently, new treatment strategies are urgently needed. Here, we report that a MuSK agonist antibody alleviates poly-PR-induced NMJ deficits in C9orf72-ALS mice. The HB9-PRF/F mice, which express poly-PR proteins in motor neurons, exhibited impaired motor behavior and NMJ deficits. Mechanistically, poly-PR proteins interacted with Agrin to disrupt the interaction between Agrin and Lrp4, leading to attenuated activation of MuSK. Treatment with a MuSK agonist antibody rescued NMJ deficits, and extended the lifespan of C9orf72-ALS mice. Moreover, impaired NMJ transmission was observed in C9orf72-ALS patients. These findings identify the mechanism by which poly-PR proteins attenuate MuSK activation and NMJ transmission, highlighting the potential of promoting MuSK activation with an agonist antibody as a therapeutic strategy to protect NMJ function and prolong the lifespan of ALS patients.
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Affiliation(s)
- Shuangshuang Sun
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Yihui Shen
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Xu Zhang
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Ning Ding
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Zhe Xu
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Qijie Zhang
- Department of Neurology, Fujian Institute of Neurology, The First Affiliated Hospital, Fujian Medical University, Fuzhou 350005, China.
| | - Lei Li
- School of Life Science and Technology, ShanghaiTech University, Shanghai 201210, China.
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2
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Brandsema JF, Ginsberg M, Hoshino H, Mimaki M, Nagata S, Rao VK, Ruzhansky K, Suresh N, Tiongson E, Yamanouchi H, Frick G, Hicks E, Liao S, Howard JF. Eculizumab in Adolescent Patients With Refractory Generalized Myasthenia Gravis: A Phase 3, Open-Label, Multicenter Study. Pediatr Neurol 2024; 156:198-207. [PMID: 38810600 DOI: 10.1016/j.pediatrneurol.2024.04.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 03/10/2024] [Accepted: 04/21/2024] [Indexed: 05/31/2024]
Abstract
BACKGROUND This study evaluated the efficacy and safety of eculizumab, a terminal complement C5 inhibitor, in juvenile generalized myasthenia gravis (gMG). METHODS Adolescents aged 12 to 17 years with refractory anti-acetylcholine receptor (AChR) antibody-positive gMG received eculizumab (weekly induction [one to two doses of 600 mg or four doses of 900 mg] followed by maintenance doses [300 to 1200 mg] every two weeks for up to 26 weeks) in a phase 3, open-label multicenter study (NCT03759366). Change from baseline to week 26 in Quantitative Myasthenia Gravis (QMG) total score (primary end point) and secondary end points including Myasthenia Gravis-Activities of Daily Living (MG-ADL) total score, Myasthenia Gravis Composite score, Myasthenia Gravis Foundation of America postintervention status, EuroQol 5-Dimensions (Youth) and Neurological Quality-of-Life Pediatric Fatigue questionnaire scores, as well as pharmacokinetics, pharmacodynamics, and safety, were recorded. RESULTS Eleven adolescents (mean ± S.D. age 14.8 ± 1.8 years) were enrolled; 10 completed the primary evaluation period. Least-squares mean changes from baseline at week 26 were -5.8 (standard error [SE] 1.2; P = 0.0004) for QMG total score and -2.3 (SE 0.6; P = 0.0017) for MG-ADL total score. Overall, the primary and all secondary efficacy end point analyses met statistical significance from the first assessment and were sustained throughout. Complete terminal complement inhibition was sustained through 26 weeks in all patients. Treatment-emergent adverse events were all mild/moderate and predominantly unrelated to eculizumab. CONCLUSIONS Eculizumab was effective in reducing disease burden and was well tolerated in adolescents with refractory AChR antibody-positive gMG.
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Affiliation(s)
- John F Brandsema
- Division of Neurology, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania
| | | | - Hideki Hoshino
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
| | - Masakazu Mimaki
- Department of Pediatrics, Teikyo University School of Medicine, Tokyo, Japan
| | - Satoru Nagata
- Department of Pediatrics, Tokyo Women's Medical University School of Medicine, Tokyo, Japan
| | - Vamshi K Rao
- Division of Neurology, Lurie Children's Hospital, Department of Pediatrics, Northwestern University Feinberg School of Medicine, Chicago, Illinois
| | - Katherine Ruzhansky
- Department of Neurology, Medical University of South Carolina, Charleston, South Carolina
| | - Niraja Suresh
- Department of Neurology, University of South Florida, Tampa, Florida
| | - Emmanuelle Tiongson
- Division of Neurology, Children's Hospital Los Angeles, Los Angeles, California
| | - Hideo Yamanouchi
- Department of Pediatrics, Comprehensive Epilepsy Center, Saitama Medical University, Saitama, Japan
| | - Glen Frick
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts.
| | - Eden Hicks
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts
| | - Serena Liao
- Alexion, AstraZeneca Rare Disease, Boston, Massachusetts
| | - James F Howard
- Department of Neurology, The University of North Carolina, Chapel Hill, North Carolina
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3
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Shu J, Xie W, Chen Z, Offringa R, Hu Y, Mei H. The enchanting canvas of CAR technology: Unveiling its wonders in non-neoplastic diseases. MED 2024; 5:495-529. [PMID: 38608709 DOI: 10.1016/j.medj.2024.03.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 12/08/2023] [Accepted: 03/19/2024] [Indexed: 04/14/2024]
Abstract
Chimeric antigen receptor (CAR) T cells have made a groundbreaking advancement in personalized immunotherapy and achieved widespread success in hematological malignancies. As CAR technology continues to evolve, numerous studies have unveiled its potential far beyond the realm of oncology. This review focuses on the current applications of CAR-based cellular platforms in non-neoplastic indications, such as autoimmune, infectious, fibrotic, and cellular senescence-associated diseases. Furthermore, we delve into the utilization of CARs in non-T cell populations such as natural killer (NK) cells and macrophages, highlighting their therapeutic potential in non-neoplastic conditions and offering the potential for targeted, personalized therapies to improve patient outcomes and enhanced quality of life.
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Affiliation(s)
- Jinhui Shu
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China; Hubei Clinical Medical Center of Cell Therapy for Neoplastic Disease, Wuhan 430022, China
| | - Wei Xie
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China; Hubei Clinical Medical Center of Cell Therapy for Neoplastic Disease, Wuhan 430022, China
| | - Zhaozhao Chen
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China; Hubei Clinical Medical Center of Cell Therapy for Neoplastic Disease, Wuhan 430022, China
| | - Rienk Offringa
- Department of General, Visceral and Transplantation Surgery, University Hospital Heidelberg, 69120 Heidelberg, Germany; Division of Molecular Oncology of Gastrointestinal Tumors, German Cancer Research Center, 69120 Heidelberg, Germany
| | - Yu Hu
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China; Hubei Clinical Medical Center of Cell Therapy for Neoplastic Disease, Wuhan 430022, China
| | - Heng Mei
- Institute of Hematology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, 1277 Jiefang Avenue, Wuhan, Hubei 430022, China; Hubei Clinical Medical Center of Cell Therapy for Neoplastic Disease, Wuhan 430022, China.
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4
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Butenko O, Jensen SM, Fillié-Grijpma YE, Verpalen R, Verschuuren JJ, van der Maarel SM, Huijbers MG, Plomp JJ. Change of voltage-gated sodium channel repertoire in skeletal muscle of a MuSK myasthenia gravis mouse model. Eur J Neurosci 2024; 59:3292-3308. [PMID: 38650308 DOI: 10.1111/ejn.16347] [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: 09/15/2023] [Revised: 03/11/2024] [Accepted: 03/23/2024] [Indexed: 04/25/2024]
Abstract
Muscle-specific kinase myasthenia gravis (MuSK MG) is caused by autoantibodies against MuSK in the neuromuscular junction (NMJ). MuSK MG patients have fluctuating, fatigable skeletal muscle weakness, in particular of bulbar muscles. Severity differs greatly between patients, in spite of comparable autoantibody levels. One explanation for inter-patient and inter-muscle variability in sensitivity might be variations in compensatory muscle responses. Previously, we developed a passive transfer mouse model for MuSK MG. In preliminary ex vivo experiments, we observed that muscle contraction of some mice, in particular those with milder myasthenia, had become partially insensitive to inhibition by μ-Conotoxin-GIIIB, a blocker of skeletal muscle NaV1.4 voltage-gated sodium channels. We hypothesised that changes in NaV channel expression profile, possibly co-expression of (μ-Conotoxin-GIIIB insensitive) NaV1.5 type channels, might lower the muscle fibre's firing threshold and facilitate neuromuscular synaptic transmission. To test this hypothesis, we here performed passive transfer in immuno-compromised mice, using 'high', 'intermediate' and 'low' dosing regimens of purified MuSK MG patient IgG4. We compared myasthenia levels, μ-Conotoxin-GIIIB resistance and muscle fibre action potential characteristics and firing thresholds. High- and intermediate-dosed mice showed clear, progressive myasthenia, not seen in low-dosed animals. However, diaphragm NMJ electrophysiology demonstrated almost equal myasthenic severities amongst all regimens. Nonetheless, low-dosed mouse diaphragms showed a much higher degree of μ-Conotoxin-GIIIB resistance. This was not explained by upregulation of Scn5a (the NaV1.5 gene), lowered muscle fibre firing thresholds or histologically detectable upregulated NaV1.5 channels. It remains to be established which factors are responsible for the observed μ-Conotoxin-GIIIB insensitivity and whether the NaV repertoire change is compensatory beneficial or a bystander effect.
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Affiliation(s)
- Olena Butenko
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Stine Marie Jensen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Robyn Verpalen
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
| | - Jan J Verschuuren
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | | | - Maartje G Huijbers
- Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Jaap J Plomp
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
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5
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Tsai NW, Chien LN, Hung C, Kuo A, Chiu YT, Lin HW, Jian LS, Chou KP, Yeh JH. Epidemiology, Patient Characteristics, and Treatment Patterns of Myasthenia Gravis in Taiwan: A Population-Based Study. Neurol Ther 2024; 13:809-824. [PMID: 38678112 PMCID: PMC11136923 DOI: 10.1007/s40120-024-00619-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Accepted: 04/05/2024] [Indexed: 04/29/2024] Open
Abstract
INTRODUCTION Myasthenia gravis (MG) is a chronic neuromuscular disease leading to significant disease burden. This study aimed to investigate the epidemiology of MG in Taiwan. METHODS A retrospective study was conducted using the Taiwan National Health Insurance Research Database. Prevalent patients with MG diagnosis (either ocular or generalized MG) from 2013 to 2019 were identified, and 2813 patients with initial MG diagnosis from 2014 to 2019 were further defined as the incident cohort. Patient characteristics, treatment patterns, and the occurrence of MG-related events were analyzed. RESULTS The number of prevalent patients with MG increased from 4476 in 2013 to 5752 in 2019, with the prevalence rate increasing from 19 to 24 per 100,000 population. The incidence rate also slightly increased from 1.9 to 2.3 per 100,000 population during the study period. Almost all incident patients (99%, n = 2791) received MG-related treatment during the follow-up period. Among 1876 patients who received monotherapy as their initial treatment in the outpatient setting, the mean time from the index date to initial treatment was 48.8 (standard deviation 164.3) days, and most patients received acetylcholinesterase inhibitors (88.5%, n = 1661) as their initial treatment. During the first year after the index date, 133 (4.7%) incident patients experienced their first myasthenic crisis, and 96.2% of these events occurred within 3 months. CONCLUSION The prevalence of MG increased steadily in Taiwan, and the treatment of patients with MG was consistent with guidelines. Despite a high treatment rate, patients still experienced MG-related events, highlighting the limitation of current treatments and emphasizing the need for early intervention and novel treatment approaches.
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Affiliation(s)
- Nai-Wen Tsai
- Department of Neurology, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
- College of Medicine, Chang Gung University, Taoyuan, Taiwan
- School of Medicine, College of Medicine, National Sun Yat-sen University, Kaohsiung, Taiwan
| | - Li-Nien Chien
- Institute of Health and Welfare Policy, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | | | | | - Yu-Ting Chiu
- Institute of Health and Welfare Policy, College of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan
| | - Hung-Wei Lin
- Real World Solutions, IQVIA Solutions Taiwan Ltd., Taipei, Taiwan
| | - Li-Shan Jian
- Real World Solutions, IQVIA Solutions Taiwan Ltd., Taipei, Taiwan
| | - Kai-Pei Chou
- Real World Solutions, IQVIA Solutions Taiwan Ltd., Taipei, Taiwan
| | - Jiann-Horng Yeh
- Department of Neurology, Shin Kong Wu Ho-Su Memorial Hospital, Taipei, Taiwan.
- School of Medicine, College of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
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6
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Alfaidi N, Karmastaji S, Matic A, Bril V. FcRn Inhibitor Therapies in Neurologic Diseases. CNS Drugs 2024; 38:425-441. [PMID: 38724842 DOI: 10.1007/s40263-024-01090-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/11/2024] [Indexed: 05/18/2024]
Abstract
In the last decade, the landscape of treating autoimmune diseases has evolved with the emergence and approval of novel targeted therapies. Several new biological agents offer selective and target-specific immunotherapy and therefore fewer side effects, such as neonatal Fc receptor (FcRn)-targeting therapy. Neonatal Fc receptor-targeted therapies are engineered to selectively target FcRn through various methods, such as Fc fragments or monoclonal anti-FcRn antibodies. These approaches enhance the breakdown of autoantibodies by blocking the immunoglobulin G recycling pathway. This mechanism reduces overall plasma immunoglobulin levels, including the levels of pathogenic autoantibodies, without affecting the other immunoglobulin class immunoglobulin A, immunoglobulin E, immunoglobulin M, and immunoglobulin D levels. Drugs that inhibit FcRn include efgartigimod, rozanolixizumab, batoclimab, and nipocalimab. These medications can be administered either intravenously or subcutaneously. Numerous clinical trials are currently underway to investigate their effectiveness, safety, and tolerability in various neurological conditions, including myasthenia gravis and other neurological disorders such as chronic inflammatory demyelinating polyneuropathy, myositis, neuromyelitis optica, and myelin oligodendrocyte glycoprotein antibody disease. Positive results from clinical trials of efgartigimod and rozanolixizumab led to their approval for the treatment of generalized myasthenia gravis. Additional clinical trials are still ongoing. Neonatal Fc receptor inhibitor agents seem to be well tolerated. Reported adverse events include headache (most commonly observed with efgartigimod and rozanolixizumab), upper respiratory tract infection, urinary tract infection, diarrhea, pyrexia, and nausea. Additionally, some of these agents may cause transient hypoalbuminemia and hypercholesterolemia notably reported with batoclimab and nipocalimab. In this review, we discuss the available clinical data for FcRN inhibitor agents in treating different neurological autoimmune diseases.
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Affiliation(s)
- Nouf Alfaidi
- Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital, University Health Network, University of Toronto, 5EC-309, TGH 200 Elizabeth St, Toronto, ON, M5G 2C4, Canada
| | - Salama Karmastaji
- Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital, University Health Network, University of Toronto, 5EC-309, TGH 200 Elizabeth St, Toronto, ON, M5G 2C4, Canada
| | - Alexandria Matic
- Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital, University Health Network, University of Toronto, 5EC-309, TGH 200 Elizabeth St, Toronto, ON, M5G 2C4, Canada
| | - Vera Bril
- Ellen and Martin Prosserman Centre for Neuromuscular Diseases, Toronto General Hospital, University Health Network, University of Toronto, 5EC-309, TGH 200 Elizabeth St, Toronto, ON, M5G 2C4, Canada.
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7
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Jacob S. Treating myasthenia gravis beyond the eye clinic. Eye (Lond) 2024:10.1038/s41433-024-03133-x. [PMID: 38789789 DOI: 10.1038/s41433-024-03133-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Revised: 02/17/2024] [Accepted: 05/07/2024] [Indexed: 05/26/2024] Open
Abstract
Myasthenia gravis (MG) is one of the most well characterised autoimmune disorders affecting the neuromuscular junction with autoantibodies targeting the acetylcholine receptor (AChR) complex. The vast majority of patients present with ocular symptoms including double vision and ptosis, but may progress on to develop generalised fatiguable muscle weakness. Severe involvement of the bulbar muscles can lead to dysphagia, dysarthria and breathing difficulties which can progress to myasthenic crisis needing ventilatory support. Given the predominant ocular onset of the disease, it is important that ophthalmologists are aware of the differential diagnosis, investigations and management including evolving therapies. When the disease remains localised to the extraocular muscles (ocular MG) IgG1 and IgG3 antibodies against the AChR (including clustered AChR) are present in nearly 50% of patients. In generalised MG this is seen in nearly 90% patients. Other antibodies include those against muscle specific tyrosine kinase (MuSK) and lipoprotein receptor related protein 4 (LRP4). Even though decremental response on repetitive nerve stimulation is the most well recognised neurophysiological abnormality, single fibre electromyogram (SFEMG) in experienced hands is the most sensitive test which helps in the diagnosis. Initial treatment should be using cholinesterase inhibitors and then proceeding to immunosuppression using corticosteroids and steroid sparing drugs. Patients requiring bulbar muscle support may need rescue therapies including plasma exchange and intravenous immunoglobulin (IVIg). Newer therapeutic targets include those against the B lymphocytes, complement system, neonatal Fc receptors (FcRn) and various other elements of the immune system.
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Affiliation(s)
- Saiju Jacob
- University Hospitals Birmingham, Birmingham, UK.
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, UK.
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8
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Wu Q, Xia Y, Guo MS, Au TY, Yuen GKW, Kong I, Wang Z, Lin Y, Dong TTX, Tsim KWK. Acetylcholinesterase is regulated by exposure of ultraviolet B in skin keratinocytes: A potential inducer of cholinergic urticaria. FASEB J 2024; 38:e23641. [PMID: 38690717 DOI: 10.1096/fj.202400146r] [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: 01/19/2024] [Revised: 03/25/2024] [Accepted: 04/18/2024] [Indexed: 05/02/2024]
Abstract
Cholinergic urticaria is a dermatological disease characterized by the presence of large patches of red skin and transient hives triggered by factors, such as exercise, sweating, and psychological tension. This skin problem is hypothesized to be attributed to a reduced expression of acetylcholinesterase (AChE), an enzyme responsible for hydrolyzing acetylcholine (ACh). Consequently, ACh is thought to the leak from sympathetic nerves to skin epidermis. The redundant ACh stimulates the mast cells to release histamine, triggering immune responses in skin. Here, the exposure of ultraviolet B in skin suppressed the expression of AChE in keratinocytes, both in in vivo and in vitro models. The decrease of the enzyme was resulted from a declined transcription of ACHE gene mediated by micro-RNAs, that is, miR-132 and miR-212. The levels of miR-132 and miR-212 were markedly induced by exposure to ultraviolet B, which subsequently suppressed the transcriptional rate of ACHE. In the presence of low level of AChE, the overflow ACh caused the pro-inflammatory responses in skin epidermis, including increased secretion of cytokines and COX-2. These findings suggest that ultraviolet B exposure is one of the factors contributing to cholinergic urticaria in skin.
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Affiliation(s)
- Qiyun Wu
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
- Shenzhen Key Laboratory of Edible and Medicinal Bioresources, HKUST Shenzhen Research Institute, Hi-Tech Park, Shenzhen, China
| | - Yingjie Xia
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Maggie Suisui Guo
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tsz Yu Au
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Gary K W Yuen
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Ivan Kong
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Zhengqi Wang
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Yingyi Lin
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
| | - Tina T X Dong
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
- Shenzhen Key Laboratory of Edible and Medicinal Bioresources, HKUST Shenzhen Research Institute, Hi-Tech Park, Shenzhen, China
| | - Karl W K Tsim
- Division of Life Science and State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Hong Kong, China
- Shenzhen Key Laboratory of Edible and Medicinal Bioresources, HKUST Shenzhen Research Institute, Hi-Tech Park, Shenzhen, China
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9
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Querol L, De Sèze J, Dysgaard T, Levine T, Rao TH, Rivner M, Hartung HP, Kiessling P, Shimizu S, Marmol D, Bozorg A, Colson AO, Massow U, Eftimov F. Efficacy, safety and tolerability of rozanolixizumab in patients with chronic inflammatory demyelinating polyradiculoneuropathy: a randomised, subject-blind, investigator-blind, placebo-controlled, phase 2a trial and open-label extension study. J Neurol Neurosurg Psychiatry 2024:jnnp-2023-333112. [PMID: 38729747 DOI: 10.1136/jnnp-2023-333112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2023] [Accepted: 02/13/2024] [Indexed: 05/12/2024]
Abstract
BACKGROUND Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a peripheral nerve disorder characterised by weakness and sensory loss. We assessed the neonatal Fc receptor inhibitor rozanolixizumab for CIDP management. METHODS CIDP01 (NCT03861481) was a randomised, subject-blind, investigator-blind, placebo-controlled, phase 2a study. Adults with definite or probable CIDP receiving subcutaneous or intravenous immunoglobulin maintenance therapy were randomised 1:1 to 12 once-weekly subcutaneous infusions of rozanolixizumab 10 mg/kg or placebo, stratified according to previous immunoglobulin administration route. Investigators administering treatment and assessing efficacy, and patients, were blinded. The primary outcome was a change from baseline (CFB) to day 85 in inflammatory Rasch-built Overall Disability Scale (iRODS) score. Eligible patients who completed CIDP01 entered the open-label extension CIDP04 (NCT04051944). RESULTS In CIDP01, between 26 March 2019 and 31 March 2021, 34 patients were randomised to rozanolixizumab or placebo (17 (50%) each). No significant difference in CFB to day 85 in iRODS centile score was observed between rozanolixizumab (least squares mean 2.0 (SE 3.2)) and placebo (3.4 (2.6); difference -1.5 (90% CI -7.5 to 4.5)). Overall, 14 (82%) patients receiving rozanolixizumab and 13 (76%) receiving placebo experienced a treatment-emergent adverse event during the treatment period. Across CIDP01 and CIDP04, rozanolixizumab was well tolerated over up to 614 days; no clinically meaningful efficacy results were seen. No deaths occurred. CONCLUSIONS Rozanolixizumab did not show efficacy in patients with CIDP in this study, although this could be due to a relatively high placebo stability rate. Rozanolixizumab was well tolerated over medium-to-long-term weekly use, with an acceptable safety profile.
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Affiliation(s)
- Luis Querol
- Neuromuscular Diseases Unit - Neurology Department, Hospital de la Santa Creu i Sant Pau, Autonomous University of Barcelona, Barcelona, Spain
- Center for Network Research in Rare Diseases - CIBERER, Madrid, Spain
| | - Jérôme De Sèze
- Department of Neurology, Clinical Investigation Centre, University Hospital of Strasbourg, Strasbourg, France
| | - Tina Dysgaard
- Department of Neurology, Copenhagen Neuromuscular Center, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Todd Levine
- Honor Health Neurology, Bob Bové Neuroscience Institute, Scottsdale, Arizona, USA
| | - T Hemanth Rao
- The Neurological Institute, PA, Charlotte, North Carolina, USA
| | - Michael Rivner
- Department of Neurology, Augusta University, Augusta, Atlanta, Georgia, USA
| | - Hans-Peter Hartung
- Department of Neurology, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany
- Brain and Mind Center, Medical Faculty, University of Sydney, Sydney, New South Wales, Australia
- Department of Neurology, Palacký University, Olomouc, Czech Republic
| | | | | | | | - Ali Bozorg
- UCB Pharma, Morrisville, North Carolina, USA
| | | | | | - Filip Eftimov
- Department of Neurology, Amsterdam Neuroscience, Amsterdam University Medical Centers, University of Amsterdam, Amsterdam, The Netherlands
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10
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Bicskó RR, Illés Á, Hevessy Z, Ivády G, Kerekes G, Méhes G, Csépány T, Gergely L. Eculizumab Treatment of Massive Hemolysis Occurring in a Rare Co-Existence of Paroxysmal Nocturnal Hemoglobinuria and Myasthenia Gravis. Hematol Rep 2024; 16:255-259. [PMID: 38651454 PMCID: PMC11036238 DOI: 10.3390/hematolrep16020025] [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: 02/05/2024] [Revised: 04/02/2024] [Accepted: 04/16/2024] [Indexed: 04/25/2024] Open
Abstract
The co-occurrence of myasthenia gravis (MG) and paroxysmal nocturnal hemoglobinuria (PNH) is rare; only one case has been published so far. We report a 63-year-old Caucasian female patient who was diagnosed with MG at the age of 43. Thymoma was also detected, and so it was surgically resected, which resulted in reasonable disease control for nearly 20 years. Slight hemolysis began to emerge, and then myasthenia symptoms progressed, so immunosuppressive therapy was started. Due to progressive disease and respiratory failure, the patient underwent plasmapheresis, and ventilatory support was stopped. Marked hemolysis was present, and diagnostic tests confirmed PNH with type III PNH cells. Her myasthenia symptoms aggravated, mechanical ventilation had to be started again, and due to the respiratory acidosis, massive hemolysis occurred. After two plasmapheresis sessions, the patient received eculizumab at 600 mg, resulting in prompt hemolysis control. After the second dose of the treatment, the patient was extubated. Still, due to their inability to cough, she developed another respiratory failure and pneumonia-sepsis, resulting in the patient's death. This case highlights the rare association between these two serious diseases and similar immune-mediated pathophysiology mechanisms involving the complement system.
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Affiliation(s)
- Ráhel Réka Bicskó
- Department of Hematology, Institute of Internal Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary; (Á.I.); (L.G.)
| | - Árpád Illés
- Department of Hematology, Institute of Internal Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary; (Á.I.); (L.G.)
| | - Zsuzsanna Hevessy
- Department of Laboratory Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary; (Z.H.); (G.I.)
| | - Gergely Ivády
- Department of Laboratory Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary; (Z.H.); (G.I.)
| | - György Kerekes
- Intensive Care Unit, Institute of Internal Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary;
| | - Gábor Méhes
- Department of Pathology, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary;
| | - Tünde Csépány
- Department of Neurology, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary;
| | - Lajos Gergely
- Department of Hematology, Institute of Internal Medicine, Faculty of Medicine, Clinical Center, University of Debrecen, 4032 Debrecen, Hungary; (Á.I.); (L.G.)
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11
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Ünlü S, Sánchez Navarro BG, Cakan E, Berchtold D, Meleka Hanna R, Vural S, Vural A, Meisel A, Fichtner ML. Exploring the depths of IgG4: insights into autoimmunity and novel treatments. Front Immunol 2024; 15:1346671. [PMID: 38698867 PMCID: PMC11063302 DOI: 10.3389/fimmu.2024.1346671] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Accepted: 02/29/2024] [Indexed: 05/05/2024] Open
Abstract
IgG4 subclass antibodies represent the rarest subclass of IgG antibodies, comprising only 3-5% of antibodies circulating in the bloodstream. These antibodies possess unique structural features, notably their ability to undergo a process known as fragment-antigen binding (Fab)-arm exchange, wherein they exchange half-molecules with other IgG4 antibodies. Functionally, IgG4 antibodies primarily block and exert immunomodulatory effects, particularly in the context of IgE isotype-mediated hypersensitivity reactions. In the context of disease, IgG4 antibodies are prominently observed in various autoimmune diseases combined under the term IgG4 autoimmune diseases (IgG4-AID). These diseases include myasthenia gravis (MG) with autoantibodies against muscle-specific tyrosine kinase (MuSK), nodo-paranodopathies with autoantibodies against paranodal and nodal proteins, pemphigus vulgaris and foliaceus with antibodies against desmoglein and encephalitis with antibodies against LGI1/CASPR2. Additionally, IgG4 antibodies are a prominent feature in the rare entity of IgG4 related disease (IgG4-RD). Intriguingly, both IgG4-AID and IgG4-RD demonstrate a remarkable responsiveness to anti-CD20-mediated B cell depletion therapy (BCDT), suggesting shared underlying immunopathologies. This review aims to provide a comprehensive exploration of B cells, antibody subclasses, and their general properties before examining the distinctive characteristics of IgG4 subclass antibodies in the context of health, IgG4-AID and IgG4-RD. Furthermore, we will examine potential therapeutic strategies for these conditions, with a special focus on leveraging insights gained from anti-CD20-mediated BCDT. Through this analysis, we aim to enhance our understanding of the pathogenesis of IgG4-mediated diseases and identify promising possibilities for targeted therapeutic intervention.
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Affiliation(s)
- Selen Ünlü
- Koç University Research Center for Translational Medicine (KUTTAM), İstanbul, Türkiye
- Koç University School of Medicine, Istanbul, Türkiye
| | - Blanca G. Sánchez Navarro
- Department of Neurology with Experimental Neurology, Integrated Myasthenia Gravis Center, Neuroscience Clinical Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Elif Cakan
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology and Harvard University, Cambridge, MA, United States
| | - Daniel Berchtold
- Department of Neurology with Experimental Neurology, Integrated Myasthenia Gravis Center, Neuroscience Clinical Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Rafael Meleka Hanna
- Department of Neurology with Experimental Neurology, Integrated Myasthenia Gravis Center, Neuroscience Clinical Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Secil Vural
- Koç University Research Center for Translational Medicine (KUTTAM), İstanbul, Türkiye
- Department of Dermatology and Venereology, Koç University School of Medicine, İstanbul, Türkiye
| | - Atay Vural
- Koç University Research Center for Translational Medicine (KUTTAM), İstanbul, Türkiye
- Department of Neurology, Koç University School of Medicine, İstanbul, Türkiye
| | - Andreas Meisel
- Department of Neurology with Experimental Neurology, Integrated Myasthenia Gravis Center, Neuroscience Clinical Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
| | - Miriam L. Fichtner
- Koç University Research Center for Translational Medicine (KUTTAM), İstanbul, Türkiye
- Department of Neurology with Experimental Neurology, Integrated Myasthenia Gravis Center, Neuroscience Clinical Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
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12
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Tannemaat MR, Huijbers MG, Verschuuren JJGM. Myasthenia gravis-Pathophysiology, diagnosis, and treatment. HANDBOOK OF CLINICAL NEUROLOGY 2024; 200:283-305. [PMID: 38494283 DOI: 10.1016/b978-0-12-823912-4.00026-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/19/2024]
Abstract
Myasthenia gravis (MG) is an autoimmune disease characterized by dysfunction of the neuromuscular junction resulting in skeletal muscle weakness. It is equally prevalent in males and females, but debuts at a younger age in females and at an older age in males. Ptosis, diplopia, facial bulbar weakness, and limb weakness are the most common symptoms. MG can be classified based on the presence of serum autoantibodies. Acetylcholine receptor (AChR) antibodies are found in 80%-85% of patients, muscle-specific kinase (MuSK) antibodies in 5%-8%, and <1% may have low-density lipoprotein receptor-related protein 4 (Lrp4) antibodies. Approximately 10% of patients are seronegative for antibodies binding the known disease-related antigens. In patients with AChR MG, 10%-20% have a thymoma, which is usually detected at the onset of the disease. Important differences between clinical presentation, treatment responsiveness, and disease mechanisms have been observed between these different serologic MG classes. Besides the typical clinical features and serologic testing, the diagnosis can be established with additional tests, including repetitive nerve stimulation, single fiber EMG, and the ice pack test. Treatment options for MG consist of symptomatic treatment (such as pyridostigmine), immunosuppressive treatment, or thymectomy. Despite the treatment with symptomatic drugs, steroid-sparing immunosuppressants, intravenous immunoglobulins, plasmapheresis, and thymectomy, a large proportion of patients remain chronically dependent on corticosteroids (CS). In the past decade, the number of treatment options for MG has considerably increased. Advances in the understanding of the pathophysiology have led to new treatment options targeting B or T cells, the complement cascade, the neonatal Fc receptor or cytokines. In the future, these new treatments are likely to reduce the chronic use of CS, diminish side effects, and decrease the number of patients with refractory disease.
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Affiliation(s)
- Martijn R Tannemaat
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands
| | - Maartje G Huijbers
- Department of Neurology, Leiden University Medical Center, Leiden, The Netherlands; Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands
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13
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Vu T, Wiendl H, Katsuno M, Reddel SW, Howard JF. Ravulizumab in Myasthenia Gravis: A Review of the Current Evidence. Neuropsychiatr Dis Treat 2023; 19:2639-2655. [PMID: 38059203 PMCID: PMC10697093 DOI: 10.2147/ndt.s374694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 10/17/2023] [Indexed: 12/08/2023] Open
Abstract
The terminal complement C5 inhibitor ravulizumab was engineered from the humanized monoclonal antibody eculizumab to have an extended half-life and duration of action. It binds to human terminal complement protein C5, inhibiting its cleavage into C5a and C5b, thus preventing the cascade of events that lead to architectural destruction of the postsynaptic neuromuscular junction membrane by the membrane attack complex, and consequent muscle weakness in patients with anti-acetylcholine receptor (AChR) antibody-positive generalized myasthenia gravis (gMG). The 26-week randomized, placebo-controlled period (RCP) of the phase 3 CHAMPION MG study demonstrated the rapid efficacy of ravulizumab in reducing MG symptoms. Weight-based dosing of ravulizumab every 8 weeks provided sustained efficacy, in terms of patient-reported (Myasthenia Gravis-Activities of Daily Living) and clinician-reported (Quantitative Myasthenia Gravis) endpoints in patients with anti-AChR antibody-positive gMG. Pharmacokinetic and pharmacodynamic analyses showed therapeutic serum ravulizumab concentrations (>175 µg/mL) were achieved immediately after the first dose and were maintained throughout 26 weeks, irrespective of patient body weight; inhibition of serum free C5 was immediate, complete (<0.5 μg/mL), and sustained in all patients. Interim results from the open-label extension (OLE) showed that after 60 weeks, efficacy was maintained in patients continuing on ravulizumab. Rapid and sustained improvements in efficacy, similar to those seen in patients initiating ravulizumab in the RCP, were observed after initiation of ravulizumab treatment in patients who switched from placebo in the RCP to ravulizumab in the OLE. The findings from the RCP and OLE support ravulizumab's favorable safety profile. In conclusion, ravulizumab has a simple weight-based administration and long dosing interval. Its targeted mechanism of action without generalized immunosuppression is reflected in its rapid onset of symptom improvement, sustained efficacy and good safety profile in the treatment of patients with anti-AChR antibody-positive gMG.
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Affiliation(s)
- Tuan Vu
- Department of Neurology, University of South Florida Morsani College of Medicine, Tampa, FL, USA
| | - Heinz Wiendl
- Department of Neurology with Institute of Translational Neurology, University Hospital Münster, Münster, Germany
| | - Masahisa Katsuno
- Department of Neurology, Nagoya University Graduate School of Medicine, Nagoya, Japan
| | - Stephen W Reddel
- Department of Neurology, Concord Hospital, University of Sydney, Sydney, NSW, Australia
| | - James F Howard
- Department of Neurology, The University of North Carolina, Chapel Hill, NC, USA
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Almuqbil S, AlHarbi A, Alzouri FS, Elbawab HY, Alsafwani NS, Alkhunaizy Z. Primary Thymic Hodgkin Lymphoma Coexisting with Thymoma and Myasthenia Gravis: A Case Report. AMERICAN JOURNAL OF CASE REPORTS 2023; 24:e941792. [PMID: 38006204 PMCID: PMC10687740 DOI: 10.12659/ajcr.941792] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2023] [Revised: 10/23/2023] [Accepted: 10/06/2023] [Indexed: 11/26/2023]
Abstract
BACKGROUND Myasthenia gravis is a neuromuscular disorder that is strongly associated with thymoma. Although the presence of myasthenia gravis with other tumors is uncommon, approximately 50% of patients with thymoma have myasthenia gravis. Thymic Hodgkin lymphoma should be considered due to the multiple reported cases of patients with myasthenia gravis and Hodgkin lymphoma. In this report, we present the case of 24-year-old woman with myasthenia gravis who was incidentally found to have coexisting thymoma with thymic Hodgkin lymphoma. CASE REPORT A 24-year-old woman with a known case of vitiligo presented with a 2-year history of diplopia and incidental anterior mediastinal mass. Following investigations, myasthenia gravis was diagnosed and managed by pyridostigmine, prednisolone, and azathioprine. Regarding the anterior mediastinal mass, thymoma was suspected based on the presence of myasthenia gravis and radiological findings. She underwent extended transsternal thymectomy. The final histopathological report of the dissected thymus disclosed Hodgkin lymphoma pathology coexisting with thymoma. After the diagnosis of Hodgkin lymphoma nodular sclerosis type IIA was confirmed, 6 cycles of chemotherapy were administered. Four years of follow-up revealed no evidence of Hodgkin lymphoma. However, her symptoms of myasthenia gravis persisted despite Hodgkin lymphoma remission. CONCLUSIONS There is an unclear association between myasthenia gravies and Hodgkin lymphoma. Prior reports revealed regression of myasthenia gravies following Hodgkin lymphoma management, which suggests that myasthenia could be a complication of Hodgkin lymphoma. However, in our case, myasthenia gravis persisted after Hodgkin lymphoma management; therefore, further studies are needed to explore this association.
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Affiliation(s)
- Sarah Almuqbil
- College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Amal AlHarbi
- College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Fatimah S. Alzouri
- College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Hatem Yazeed Elbawab
- Thoracic Surgery Division, Department of Surgery, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Noor S. Alsafwani
- Department of Pathology, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Zahra Alkhunaizy
- Department of Pathology, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
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Bouchtout MN, Meçabih F, Boukadir C, Attal E, Daoudi S, Benkortbi H, Touil-Boukoffa C, Raache R, Attal N. Cytokines Single Nucleotide Polymorphisms (SNPs) Association With Myasthenia Gravis (MG) In Algerian Patients: A Case-Control Study On A Small Group. J Clin Neuromuscul Dis 2023; 25:18-26. [PMID: 37611266 DOI: 10.1097/cnd.0000000000000446] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/25/2023]
Abstract
ABSTRACT Myasthenia gravis (MG) is an autoimmune disease of multifactorial etiology in which genetic factors and cytokines seem to play an important role. The aim of this study was to investigate potential associations of cytokines single nucleotide polymorphisms (SNPs) and MG in Algerian patients. We performed a case-control study that included 27 patients and 74 healthy subjects. Cytokines SNPs genotyping was performed by the polymerase chain reaction sequence-specific primers (PCR-SSP) method. Our results showed that the TNF-α -308G/A (P < 0.005) and TGF-β1 +869T/T (P < 0.05) genotypes were more frequent among patients with MG compared with healthy individuals, whereas TNF-α -308G/G (P < 0.0001), TGF-β1 +869T/C (P < 0.05), and IFN-γ +874A/A (P < 0.05) were less frequent. Our results also showed that IL-10 and IL-6 SNPs did not show any significant difference in distribution between MG patients and healthy individuals. Our observations support the hypothesis that implicates genetic variants of certain cytokines in MG. However, ours results should be replicated with a larger sample size. In addition, the precise underlying processes remain to be clarified. HIGHLIGHTS TNF-α -308G/A and TGF-β1 +869T/C genotypes predispose to MG.IFN-γ +874A/A genotype protects against MG.IL-6 -174C/G SNP is not associated with MG.
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Affiliation(s)
- Mohamed Nadji Bouchtout
- Laboratory of Cellular and Molecular Biology, Cytokine and NO Synthase Team, University of Science and Technology Houari Boumediene (USTHB), Algiers, Algeria
| | - Fethi Meçabih
- Immunology Department, Pasteur Institute of Algeria, Algiers, Algeria
| | - Chahrazad Boukadir
- Neurology department, Sidi Belloua Unit, University Hospital Center of Tizi Ouzou, Tizi Ouzou, Algeria
| | - Elias Attal
- Male unit of neurology, Ait Idir neurosurgery hospital, Algiers, Algeria
| | - Smail Daoudi
- Neurology department, Sidi Belloua Unit, University Hospital Center of Tizi Ouzou, Tizi Ouzou, Algeria
| | - Halla Benkortbi
- Immunology Department, Pasteur Institute of Algeria, Algiers, Algeria
| | - Chafia Touil-Boukoffa
- Laboratory of Cellular and Molecular Biology, Cytokine and NO Synthase Team, University of Science and Technology Houari Boumediene (USTHB), Algiers, Algeria
| | - Rachida Raache
- Laboratory of Cellular and Molecular Biology, Cytokine and NO Synthase Team, University of Science and Technology Houari Boumediene (USTHB), Algiers, Algeria
| | - Nabila Attal
- Immunology Department, Pasteur Institute of Algeria, Algiers, Algeria
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Huang EJC, Wu MH, Wang TJ, Huang TJ, Li YR, Lee CY. Myasthenia Gravis: Novel Findings and Perspectives on Traditional to Regenerative Therapeutic Interventions. Aging Dis 2023; 14:1070-1092. [PMID: 37163445 PMCID: PMC10389825 DOI: 10.14336/ad.2022.1215] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 12/15/2022] [Indexed: 05/12/2023] Open
Abstract
The prevalence of myasthenia gravis (MG), an autoimmune disorder, is increasing among all subsets of the population leading to an elevated economic and social burden. The pathogenesis of MG is characterized by the synthesis of autoantibodies against the acetylcholine receptor (AChR), low-density lipoprotein receptor-related protein 4 (LRP4), or muscle-specific kinase at the neuromuscular junction, thereby leading to muscular weakness and fatigue. Based on clinical and laboratory examinations, the research is focused on distinguishing MG from other autoimmune, genetic diseases of neuromuscular transmission. Technological advancements in machine learning, a subset of artificial intelligence (AI) have been assistive in accurate diagnosis and management. Besides, addressing the clinical needs of MG patients is critical to improving quality of life (QoL) and satisfaction. Lifestyle changes including physical exercise and traditional Chinese medicine/herbs have also been shown to exert an ameliorative impact on MG progression. To achieve enhanced therapeutic efficacy, cholinesterase inhibitors, immunosuppressive drugs, and steroids in addition to plasma exchange therapy are widely recommended. Under surgical intervention, thymectomy is the only feasible alternative to removing thymoma to overcome thymoma-associated MG. Although these conventional and current therapeutic approaches are effective, the associated adverse events and surgical complexity limit their wide application. Moreover, Restivo et al. also, to increase survival and QoL, further recent developments revealed that antibody, gene, and regenerative therapies (such as stem cells and exosomes) are currently being investigated as a safer and more efficacious alternative. Considering these above-mentioned points, we have comprehensively reviewed the recent advances in pathological etiologies of MG including COVID-19, and its therapeutic management.
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Affiliation(s)
- Evelyn Jou-Chen Huang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Meng-Huang Wu
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Wang
- Department of Ophthalmology, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Ophthalmology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Tsung-Jen Huang
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
| | - Yan-Rong Li
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Linkou Chang Gung Memorial Hospital and College of Medicine, Chang Gung University, Taoyuan, Taiwan.
| | - Ching-Yu Lee
- Department of Orthopedics, Taipei Medical University Hospital, Taipei, Taiwan.
- Department of Orthopaedics, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
- International PhD Program for Cell Therapy and Regeneration Medicine, College of Medicine, Taipei Medical University, Taipei 11031, Taiwan.
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Gambino CM, Agnello L, Ciaccio AM, Scazzone C, Vidali M, Di Stefano V, Milano S, Brighina F, Candore G, Lo Sasso B, Ciaccio M. Detection of Antibodies against the Acetylcholine Receptor in Patients with Myasthenia Gravis: A Comparison of Two Enzyme Immunoassays and a Fixed Cell-Based Assay. J Clin Med 2023; 12:4781. [PMID: 37510896 PMCID: PMC10381261 DOI: 10.3390/jcm12144781] [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: 05/11/2023] [Revised: 06/28/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
The detection of serum anti-acetylcholine receptor (AChR) antibodies is currently an important tool for diagnosing myasthenia gravis (MG) since they are present in about 85% of MG patients. Many serological tests are now available. Nevertheless, results from these tests can be different in some patients. The aim of this study is to compare the sensitivity of a commercially available fixed cell-based assay (F-CBA) to that of enzyme-linked immunosorbent assay (ELISA) kits for anti-AChR detection in patients with a diagnosis of MG. Overall, 143 patients with a confirmed MG diagnosis were included in the study. The detection and measurement of serum anti-AChR antibodies were performed by three analytical methods, namely, a competitive ELISA (cELISA), an indirect ELISA (iELISA), and an F-CBA, according to the manufacturers' instructions. Anti-AChR antibody titers were positive in 94/143 (66%) using the cELISA, in 75/143 (52%) using the iELISA and in 61/143 (43%) using the F-CBA (adult and/or fetal). Method agreement, evaluated by concordant pairs and Cohen's kappa, was as follows: cELISA-iELISA: 110/143 (77%), k = 0.53 (95%CI 0.40-0.66); cELISA-F-CBA: 108/143 (76%), k = 0.53 (95%CI 0.41-0.66); iELISA-F-CBA: 121/143 (85%), k = 0.70 (95%CI 0.57-0.80). Our findings show that the cELISA has better analytical performance than the iELISA and F-CBA. However, the iELISA and F-CBA show the highest concordance.
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Affiliation(s)
- Caterina Maria Gambino
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
- Department of Laboratory Medicine, University Hospital "P. Giaccone", 90127 Palermo, Italy
| | - Luisa Agnello
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
| | - Anna Maria Ciaccio
- Department of Health Promotion, Maternal and Infant Care, Internal Medicine and Medical Specialties "G. D'Alessandro", University of Palermo, 90127 Palermo, Italy
| | - Concetta Scazzone
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
| | - Matteo Vidali
- Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, 20122 Milan, Italy
| | - Vincenzo Di Stefano
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Unit of Neurology, University of Palermo, 90127 Palermo, Italy
| | - Salvatore Milano
- Department of Laboratory Medicine, University Hospital "P. Giaccone", 90127 Palermo, Italy
| | - Filippo Brighina
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Unit of Neurology, University of Palermo, 90127 Palermo, Italy
| | - Giuseppina Candore
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
- Department of Laboratory Medicine, University Hospital "P. Giaccone", 90127 Palermo, Italy
| | - Bruna Lo Sasso
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
- Department of Laboratory Medicine, University Hospital "P. Giaccone", 90127 Palermo, Italy
| | - Marcello Ciaccio
- Department of Biomedicine, Neurosciences and Advanced Diagnostics, Institute of Clinical Biochemistry, Clinical Molecular Medicine and Clinical Laboratory Medicine, University of Palermo, 90127 Palermo, Italy
- Department of Laboratory Medicine, University Hospital "P. Giaccone", 90127 Palermo, Italy
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18
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Fan Y, Huang H, Chen X, Chen Y, Zeng X, Lin F, Chen X. Causal effect of vitamin D on myasthenia gravis: a two-sample Mendelian randomization study. Front Nutr 2023; 10:1171830. [PMID: 37538922 PMCID: PMC10394469 DOI: 10.3389/fnut.2023.1171830] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Accepted: 07/05/2023] [Indexed: 08/05/2023] Open
Abstract
Introduction Observational studies suggest that vitamin D supplementation may be effective in preventing myasthenia gravis (MG). However, the causal relationship between circulating vitamin D levels and MG remains unclear. This study aimed to examine the genetic causality of circulating vitamin D and MG using data from large population-based genome-wide association studies (GWAS). Methods SNPs (single nucleotide polymorphisms) strongly associated with exposure were selected. Two-sample Mendelian Randomization (MR) was performed with inverse variance weighting (IVW), MR-Egger (Mendelian randomization-Egger), weight median and MR-PRESSO (Mendelian randomization pleiotropy residual sum and outlier) methods. Heterogeneity was tested via IVW and MR-Egger. Pleiotropy was tested using MR-Egger intercept test and MR-PRESSO method. MR-PRESSO was also used to detect outliers. Leave-one-out analysis was used to identify SNPs with potential effect. Reverse MR analysis was also performed. Result In IVW, circulating vitamin D levels had no causal effect on MG [OR = 0.91 (0.67-1.22), p = 0.532] and MG had no causal effect on circulating vitamin D [OR = 1.01 (099-1.02), p = 0.663]. No heterogeneity or pleiotropy was observed (p > 0.05). Other MR methods also agreed with IVW results. Conclusion This study provides the causal relationship between genetically predicted circulating vitamin D levels and MG and provides new insights into the genetics of MG.
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Affiliation(s)
- Yidan Fan
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Huaiying Huang
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiangda Chen
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Yuexuan Chen
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Xiashi Zeng
- The First Clinical Medical College, Guangzhou University of Chinese Medicine, Guangzhou, China
| | - Fenwei Lin
- Guangdong East Hospital of Guangmei Development Zone Hospital of the Third Affiliated Hospital of Sun Yat-sen University, Meizhou, China
| | - Xu Chen
- The First Affiliated Hospital of Guangzhou University of Chinese Medicine, Guangzhou, China
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Bril V, Drużdż A, Grosskreutz J, Habib AA, Mantegazza R, Sacconi S, Utsugisawa K, Vissing J, Vu T, Boehnlein M, Bozorg A, Gayfieva M, Greve B, Woltering F, Kaminski HJ. Safety and efficacy of rozanolixizumab in patients with generalised myasthenia gravis (MycarinG): a randomised, double-blind, placebo-controlled, adaptive phase 3 study. Lancet Neurol 2023; 22:383-394. [PMID: 37059507 DOI: 10.1016/s1474-4422(23)00077-7] [Citation(s) in RCA: 52] [Impact Index Per Article: 52.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 02/07/2023] [Accepted: 02/10/2023] [Indexed: 04/16/2023]
Abstract
BACKGROUND Generalised myasthenia gravis is a chronic, unpredictable, and debilitating autoimmune disease. New treatments for this disease are needed because conventional therapies have limitations, such as side-effects (eg, increased infection risk) or inadequate control of symptoms. Rozanolixizumab is a neonatal Fc receptor blocker that might provide a novel therapeutic option for myasthenia gravis. We aimed to assess the safety and efficacy of rozanolixizumab for generalised myasthenia gravis. METHODS MycarinG is a randomised, double-blind, placebo-controlled, adaptive phase 3 study done at 81 outpatient centres and hospitals in Asia, Europe, and North America. We enrolled patients (aged ≥18 years) with acetylcholine receptor (AChR) or muscle-specific kinase (MuSK) autoantibody-positive generalised myasthenia gravis (Myasthenia Gravis Foundation of America class II-IVa), a Myasthenia Gravis Activities of Daily Living (MG-ADL) score of at least 3 (non-ocular symptoms), and a quantitative myasthenia gravis score of at least 11. Patients were randomly assigned (1:1:1) to receive subcutaneous infusions once a week for 6 weeks of either rozanolixizumab 7 mg/kg, rozanolixizumab 10 mg/kg, or placebo. Randomisation was stratified by AChR and MuSK autoantibody status. Investigators, patients, and people assessing outcomes were masked to random assignments. The primary efficacy endpoint was change from baseline to day 43 in MG-ADL score, assessed in the intention-to-treat population. Treatment-emergent adverse events (TEAEs) were assessed in all randomly assigned patients who received at least one dose of study drug. This trial is registered with ClinicalTrials.gov (NCT03971422) and EudraCT (2019-000968-18); an open-label extension study has been completed (NCT04124965; EudraCT 2019-000969-21) and another is underway (NCT04650854; EudraCT 2020-003230-20). FINDINGS Between June 3, 2019, and June 30, 2021, 300 patients were assessed for eligibility, of whom 200 were enrolled. 66 (33%) were randomly assigned to rozanolixizumab 7 mg/kg, 67 (34%) to rozanolixizumab 10 mg/kg, and 67 (34%) to placebo. Reductions in MG-ADL score from baseline to day 43 were greater in the rozanolixizumab 7 mg/kg group (least-squares mean change -3·37 [SE 0·49]) and in the rozanolixizumab 10 mg/kg group (-3·40 [0·49]) than with placebo (-0·78 [0·49]; for 7 mg/kg, least-squares mean difference -2·59 [95% CI -4·09 to -1·25], p<0·0001; for 10 mg/kg, -2·62 [-3·99 to -1·16], p<0·0001). TEAEs were experienced by 52 (81%) of 64 patients treated with rozanolixizumab 7 mg/kg, 57 (83%) of 69 treated with rozanolixizumab 10 mg/kg, and 45 (67%) of 67 treated with placebo. The most frequent TEAEs were headache (29 [45%] patients in the rozanolixizumab 7 mg/kg group, 26 [38%] in the rozanolixizumab 10 mg/kg group, and 13 [19%] in the placebo group), diarrhoea (16 [25%], 11 [16%], and nine [13%]), and pyrexia (eight [13%], 14 [20%], and one [1%]). Five (8%) patients in the rozanolixizumab 7 mg/kg group, seven (10%) in the rozanolixizumab 10 mg/kg group, and six (9%) in the placebo group had a serious TEAE. No deaths occurred. INTERPRETATION Rozanolixizumab showed clinically meaningful improvements in patient-reported and investigator-assessed outcomes in patients with generalised myasthenia gravis, for both 7 mg/kg and 10 mg/kg doses. Both doses were generally well tolerated. These findings support the mechanism of action of neonatal Fc receptor inhibition in generalised myasthenia gravis. Rozanolixizumab represents a potential additional treatment option for patients with generalised myasthenia gravis. FUNDING UCB Pharma.
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Affiliation(s)
- Vera Bril
- University Health Network, Toronto, ON, Canada.
| | - Artur Drużdż
- Department of Neurology, Municipal Hospital, Poznań, Poland
| | - Julian Grosskreutz
- Precision Neurology, Department of Neurology, University of Lübeck, Lübeck, Germany
| | - Ali A Habib
- MDA ALS and Neuromuscular Center, University of California, Irvine, CA, USA
| | - Renato Mantegazza
- Fondazione Istituto di Ricovero e Cura a Carattere Scientifico, Istituto Nazionale Neurologico Carlo Besta, Milan, Italy
| | - Sabrina Sacconi
- Université Côte d'Azur, Peripheral Nervous System and Muscle Department, Pasteur 2 Hospital, Centre Hospitalier Universitaire de Nice, Nice, France
| | | | - John Vissing
- Copenhagen Neuromuscular Center, Department of Neurology, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark
| | - Tuan Vu
- Department of Neurology, University of South Florida Morsani College of Medicine, Tampa, FL, USA
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Meisel A, Annane D, Vu T, Mantegazza R, Katsuno M, Aguzzi R, Frick G, Gault L, Howard JF. Long-term efficacy and safety of ravulizumab in adults with anti-acetylcholine receptor antibody-positive generalized myasthenia gravis: results from the phase 3 CHAMPION MG open-label extension. J Neurol 2023:10.1007/s00415-023-11699-x. [PMID: 37103755 PMCID: PMC10134722 DOI: 10.1007/s00415-023-11699-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/29/2023] [Accepted: 03/30/2023] [Indexed: 04/28/2023]
Abstract
INTRODUCTION Ravulizumab demonstrated efficacy and an acceptable safety profile versus placebo in the randomized controlled period (RCP) of the phase 3 CHAMPION MG trial in patients with anti-acetylcholine receptor antibody-positive generalized myasthenia gravis. We report an interim analysis of the ongoing open-label extension (OLE) designed to evaluate long-term treatment effects. METHODS Following completion of the 26-week RCP, patients could enter the OLE; patients who received ravulizumab in the RCP continued the drug; patients who previously received placebo switched to ravulizumab. Patients receive body-weight-based maintenance dosing of ravulizumab every 8 weeks. Efficacy endpoints up to 60 weeks included Myasthenia Gravis-Activities of Daily Living (MG-ADL) and Quantitative Myasthenia Gravis (QMG) scores, with least-squares (LS) mean change and 95% confidence intervals (95% CI) reported. RESULTS Long-term efficacy and safety in the OLE were analyzed in 161 and 169 patients, respectively. Improvements in all scores were maintained through 60 weeks in patients who received ravulizumab during the RCP; LS mean change from RCP baseline in MG-ADL score was - 4.0 (95% CI: - 4.8, - 3.1; p < 0.0001). Rapid (within 2 weeks) and sustained improvements occurred in patients previously receiving placebo; LS mean change in MG-ADL score from OLE baseline to Week 60 was - 1.7 (95% CI: - 2.7, - 0.8; p = 0.0007). Similar trends were seen in QMG scores. Ravulizumab treatment was associated with a decreased rate of clinical deterioration events compared with placebo. Ravulizumab was well tolerated; no meningococcal infections were reported. CONCLUSION Findings support the sustained efficacy and long-term safety of ravulizumab, administered every 8 weeks, in adults with anti-acetylcholine receptor antibody-positive generalized myasthenia gravis. CLINICALTRIALS gov identifier: NCT03920293; EudraCT: 2018-003243-39.
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Affiliation(s)
| | | | - Tuan Vu
- University of South Florida Morsani College of Medicine, Tampa, FL, USA
| | | | | | - Rasha Aguzzi
- Alexion, AstraZeneca Rare Disease, Boston, MA, USA
| | - Glen Frick
- Alexion, AstraZeneca Rare Disease, Boston, MA, USA
| | - Laura Gault
- Alexion, AstraZeneca Rare Disease, Boston, MA, USA
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Nair SS, Jacob S. Novel Immunotherapies for Myasthenia Gravis. Immunotargets Ther 2023; 12:25-45. [PMID: 37038596 PMCID: PMC10082579 DOI: 10.2147/itt.s377056] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2023] [Accepted: 03/03/2023] [Indexed: 04/07/2023] Open
Abstract
Myasthenia gravis (MG), a prototype autoimmune neurological disease, had its therapy centred on corticosteroids, non-steroidal broad-spectrum immunotherapy and cholinesterase inhibitors for several decades. Treatment-refractory MG and long-term toxicities of the medications have been major concerns with the conventional therapies. Advances in the immunology and pathogenesis of MG have ushered in an era of newer therapies which are more specific and efficacious. Complement inhibitors and neonatal Fc receptor blockers target disease-specific pathogenic mechanisms linked to myasthenia and have proven their efficacy in pivotal clinical studies. B cell-depleting agents, specifically rituximab, have also emerged as useful for the treatment of severe MG. Many more biologicals are in the pipeline and in diverse stages of development. This review discusses the evidence for the novel therapies and the specific issues related to their clinical use.
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Affiliation(s)
- Sruthi S Nair
- Department of Neurology, University Hospitals Birmingham, Birmingham, B15 2TH, UK
- Department of Neurology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, Kerala, India
| | - Saiju Jacob
- Department of Neurology, University Hospitals Birmingham, Birmingham, B15 2TH, UK
- Institute of Immunology and Immunotherapy, University of Birmingham, Birmingham, B15 2TT, UK
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22
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Betterle C, Furmaniak J, Sabbadin C, Scaroni C, Presotto F. Type 3 autoimmune polyglandular syndrome (APS-3) or type 3 multiple autoimmune syndrome (MAS-3): an expanding galaxy. J Endocrinol Invest 2023; 46:643-665. [PMID: 36609775 DOI: 10.1007/s40618-022-01994-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Accepted: 12/13/2022] [Indexed: 01/08/2023]
Abstract
BACKGROUND The number of recognised distinct autoimmune diseases (AIDs) has progressively increased over the years with more than 100 being reported today. The natural history of AIDs is characterized by progression from latent and subclinical to clinical stages and is associated with the presence of the specific circulating autoantibodies. Once presented, AIDs are generally chronic conditions. AIDs have the tendency to cluster and co-occur in a single patient. Autoimmune thyroid diseases (AITD) are the most prevalent of AIDs in the world population, and about one-third of the AITD patients also present with a non-thyroid AID during their life-span. Furthermore, patient with non-thyroid AIDs often presents with a form of AITD as a concurrent condition. Many of the clusters of AIDs are well characterized as distinctive syndromes, while some are infrequent and only described in case reports. PURPOSE In this review, we describe the wide spectrum of the combinations and the intricate relationships between AITD and the other AIDs, excluding Addison's disease. These combinations are collectively termed type 3 Autoimmune Polyglandular Syndrome (APS-3), also called type 3 Multiple Autoimmune Syndrome (MAS-3), and represent the most frequent APS in the world populations. CONCLUSIONS Numerous associations of AITD with various AIDs could be viewed as if the other AIDs were gravitating like satellites around AITD located in the center of a progressively expanding galaxy of autoimmunity.
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Affiliation(s)
- C Betterle
- Endocrine Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy.
- Chair of Clinical Immunology and Allergy, Department of Medical and Surgical Sciences, University of Padua Medical School, Via Ospedale Civile 105, 35128, Padua, Italy.
| | | | - C Sabbadin
- Endocrine Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - C Scaroni
- Endocrine Unit, Department of Medicine (DIMED), University of Padua, Padua, Italy
| | - F Presotto
- Unit of Internal Medicine, Ospedale Dell'Angelo, Mestre-Venice, Italy
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23
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Vu T, Ortiz S, Katsuno M, Annane D, Mantegazza R, Beasley KN, Aguzzi R, Howard JF. Ravulizumab pharmacokinetics and pharmacodynamics in patients with generalized myasthenia gravis. J Neurol 2023; 270:3129-3137. [PMID: 36890354 DOI: 10.1007/s00415-023-11617-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 02/06/2023] [Accepted: 02/07/2023] [Indexed: 03/10/2023]
Abstract
INTRODUCTION The terminal complement C5 inhibitor ravulizumab has a long elimination half-life, allowing maintenance dosing every 8 weeks. In the 26-week, double-blind, randomized, placebo-controlled period (RCP) of the CHAMPION MG study, ravulizumab provided rapid and sustained efficacy and was well tolerated in adults with anti-acetylcholine receptor antibody-positive (AChR Ab+) generalized myasthenia gravis (gMG). This analysis evaluated the pharmacokinetics (PK), pharmacodynamics (PD), and potential immunogenicity of ravulizumab in adults with AChR Ab+ gMG. METHODS Data were analyzed from 86 patients who received ravulizumab in the CHAMPION MG RCP. Ravulizumab dosing was weight-based: initial loading dose of 2400/2700/3000 mg on Day 1 and maintenance doses of 3000/3300/3600 mg on Day 15 and then every 8 weeks. PK parameters were estimated from serum ravulizumab concentrations determined pre- and post-dose; PD effects of ravulizumab on serum free C5 concentrations were measured; and immunogenicity was assessed using anti-drug antibody and neutralizing-antibody assays. RESULTS Target serum ravulizumab concentrations (> 175 µg/mL) were achieved immediately after the first ravulizumab dose (within 30 min of infusion completion) and maintained throughout the 26-week treatment period irrespective of patient body weight. Following the final maintenance dose, mean Cmax was 1548 µg/mL and Ctrough 587 µg/mL; no meaningful differences were noted among body-weight categories. Inhibition of serum free C5 was immediate, complete (< 0.5 μg/mL), and sustained throughout treatment in all patients. No treatment-emergent anti-drug antibodies were observed. CONCLUSIONS PK/PD evidence supports the use of ravulizumab every 8 weeks for immediate, complete, and sustained inhibition of terminal complement C5 in adults with AChR Ab+ gMG. TRIAL REGISTRATION ClinicalTrials.gov ID: NCT03920293 (April 18, 2019).
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Affiliation(s)
- Tuan Vu
- University of South Florida Morsani College of Medicine, Tampa, FL, USA
| | | | | | - Djillali Annane
- Hôpital Raymond Poincaré, University of Versailles, Garches, France
| | | | | | - Rasha Aguzzi
- Alexion, AstraZeneca Rare Disease, Boston, MA, USA
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Wiboonpong P, Setthawatcharawanich S, Korathanakhun P, Amornpojnimman T, Pruphetkaew N, Chongphattararot P, Sathirapanya C, Sathirapanya P. Comparison of Short-Term Post-Thymectomy Outcomes by Time-Weighted Dosages of Drug Requirements between Thymoma and Non-Thymoma Myasthenia Gravis Patients. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:3039. [PMID: 36833734 PMCID: PMC9959777 DOI: 10.3390/ijerph20043039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 02/04/2023] [Accepted: 02/08/2023] [Indexed: 06/18/2023]
Abstract
(1) Background: Early thymectomy is suggested in all clinically indicated myasthenia gravis (MG) patients. However, short-term clinical response after thymectomy in MG patients has been limitedly described in the literature. This study aimed to compare the 5-year post-thymectomy outcomes between thymoma (Th) and non-thymoma (non-Th) MG patients. (2) Methods: MG patients aged ≥18 years who underwent transsternal thymectomy and had tissue histopathology reports in Songklanagarind Hospital between 2002 and 2020 were enrolled in a retrospective review. The differences in the baseline demographics and clinical characteristics between ThMG and non-Th MG patients were studied. We compared the time-weighted averages (TWAs) of daily required dosages of pyridostigmine, prednisolone or azathioprine to efficiently maintain daily living activities and earnings between the MG patient groups during 5 consecutive years following thymectomy. Post-thymectomy clinical status, exacerbations or crises were followed. Descriptive statistics were used for analysis with statistical significance set at p < 0.05. (3) Results: ThMG patients had significantly older ages of onset and shorter times from the MG diagnosis to thymectomy. Male gender was the only significant factor associated with ThMG. TWAs of the daily MG treatment drug dosages required showed no differences between the groups. Additionally, the rates of exacerbations and crises were not different, but decremental trends were shown in both groups after the thymectomies. (4) Conclusions: The daily dosage requirements of MG treatment drugs were not different. There was a trend of decreasing adverse event rates despite no statistically significant differences during the first 5 years after thymectomy in ThMG and non-ThMG patients.
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Affiliation(s)
- Phattamon Wiboonpong
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | | | - Pat Korathanakhun
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Thanyalak Amornpojnimman
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Nannapat Pruphetkaew
- Epidemiology Unit, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Pensri Chongphattararot
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Chutarat Sathirapanya
- Department of Family and Preventive Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
| | - Pornchai Sathirapanya
- Department of Internal Medicine, Faculty of Medicine, Prince of Songkla University, Songkhla 90110, Thailand
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Stergiou C, Williams R, Fleming JR, Zouvelou V, Ninou E, Andreetta F, Rinaldi E, Simoncini O, Mantegazza R, Bogomolovas J, Tzartos J, Labeit S, Mayans O, Tzartos S. Immunological and Structural Characterization of Titin Main Immunogenic Region; I110 Domain Is the Target of Titin Antibodies in Myasthenia Gravis. Biomedicines 2023; 11:biomedicines11020449. [PMID: 36830985 PMCID: PMC9952892 DOI: 10.3390/biomedicines11020449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 01/25/2023] [Accepted: 02/01/2023] [Indexed: 02/08/2023] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disease caused by antibodies targeting the neuromuscular junction (NJ) of skeletal muscles. The major MG autoantigen is nicotinic acetylcholine receptor. Other autoantigens at the NJ include MuSK, LRP4 and agrin. Autoantibodies to the intra-sarcomeric striated muscle-specific gigantic protein titin, although not directed to the NJ, are invaluable biomarkers for thymoma and MG disease severity. Thymus and thymoma are critical in MG mechanisms and management. Titin autoantibodies bind to a 30 KDa titin segment, the main immunogenic region (MIR), consisting of an Ig-FnIII-FnIII 3-domain tandem, termed I109-I111. In this work, we further resolved the localization of titin epitope(s) to facilitate the development of more specific anti-titin diagnostics. For this, we expressed protein samples corresponding to 8 MIR and non-MIR titin fragments and tested 77 anti-titin sera for antibody binding using ELISA, competition experiments and Western blots. All anti-MIR antibodies were bound exclusively to the central MIR domain, I110, and to its containing titin segments. Most antibodies were bound also to SDS-denatured I110 on Western blots, suggesting that their epitope(s) are non-conformational. No significant difference was observed between thymoma and non-thymoma patients or between early- and late-onset MG. In addition, atomic 3D-structures of the MIR and its subcomponents were elucidated using X-ray crystallography. These immunological and structural data will allow further studies into the atomic determinants underlying titin-based autoimmunity, improved diagnostics and how to eventually treat titin autoimmunity associated co-morbidities.
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Affiliation(s)
| | - Rhys Williams
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | | | - Vasiliki Zouvelou
- 1st Neurology Department, Eginition Hospital, National and Kapodistrian University of Athens, 157 72 Athens, Greece
| | | | - Francesca Andreetta
- Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, 20133 Milano, Italy
| | - Elena Rinaldi
- Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, 20133 Milano, Italy
| | - Ornella Simoncini
- Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, 20133 Milano, Italy
| | - Renato Mantegazza
- Fondazione I.R.C.C.S., Istituto Neurologico Carlo Besta, 20133 Milano, Italy
| | - Julius Bogomolovas
- School of Medicine, University of California, La Jolla, San Diego, CA 92093, USA
| | - John Tzartos
- School of Medicine, Attikon University Hospital, National and Kapodistrian University of Athens, 124 62 Athens, Greece
| | - Siegfried Labeit
- DZHK Partner Site Mannheim-Heidelberg, Medical Faculty Mannheim, University of Heidelberg, 68167 Mannheim, Germany
- Myomedix GmbH, 69151 Neckargemuend, Germany
| | - Olga Mayans
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany
| | - Socrates Tzartos
- Tzartos NeuroDiagnostics, 115 23 Athens, Greece
- Hellenic Pasteur Institute, 115 21 Athens, Greece
- Department of Pharmacy, University of Patras, 265 00 Patras, Greece
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26
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Huda R. Inflammation and autoimmune myasthenia gravis. Front Immunol 2023; 14:1110499. [PMID: 36793733 PMCID: PMC9923104 DOI: 10.3389/fimmu.2023.1110499] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Accepted: 01/13/2023] [Indexed: 02/03/2023] Open
Abstract
Myasthenia gravis (MG) is a neuromuscular autoimmune disorder characterized by chronic but intermittent fatigue of the eye- and general body muscles. Muscle weakness is caused primarily by the binding of an autoantibody to the acetylcholine receptors, resulting in blockage of normal neuromuscular signal transmission. Studies revealed substantial contributions of different proinflammatory or inflammatory mediators in the pathogenesis of MG. Despite these findings, compared to therapeutic approaches that target autoantibody and complements, only a few therapeutics against key inflammatory molecules have been designed or tested in MG clinical trials. Recent research focuses largely on identifying unknown molecular pathways and novel targets involved in inflammation associated with MG. A well-designed combination or adjunct treatment utilizing one or more selective and validated promising biomarkers of inflammation as a component of targeted therapy may yield better treatment outcomes. This review briefly discusses some preclinical and clinical findings of inflammation associated with MG and current therapy approaches and suggest the potential of targeting important inflammatory marker(s) along with current monoclonal antibody or antibody fragment based targeted therapies directed to a variety of cell surface receptors.
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Nagaoka A, Tsujino A, Shiraishi H, Kanamoto T, Shima T, Yoshimura S, Miyazaki T, Tateishi Y, Tsujihata M, Motomura M, Maxwell S, Higuchi O, Beeson D, Vincent A. Motor end-plate analysis to diagnose immune-mediated myasthenia gravis in seronegative patients. J Neurol Sci 2022; 443:120494. [PMID: 36403297 DOI: 10.1016/j.jns.2022.120494] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 11/08/2022] [Accepted: 11/10/2022] [Indexed: 11/16/2022]
Abstract
This study aimed to evaluate the diagnostic usefulness of motor end-plate (MEP) analysis along with clustered acetylcholine receptor (AChR) antibody (Ab) assays in patients with myasthenia-like symptoms but negative routine AChR and muscle-specific kinase (MuSK) Ab tests. MEP analysis of muscle biopsies of the biceps brachii was performed in 20 patients to try to differentiate between those with or without immune-mediated myasthenia gravis (MG). Using a quantitative method, complement C3 deposition and AChR densities in MEPs were examined. Independently, cell-based assays were used to detect serum clustered-AChR Abs. Only five of 20 patients had complement deposition at MEPs; four of these patients had reduced AChR densities similar to those in patients with typical AChR Ab positive MG, and distinct from those in the remaining 15 patients. Two of the four serum samples from these patients had clustered-AChR Abs. All complement-positive patients were considered as having immune-mediated MG and improved with appropriate treatments; although one patient presented with MG 3 years later, the remaining patients had other diagnoses during over 10 years of follow-up. These results suggest the usefulness of MEP analysis of muscle biopsies in diagnosing immune-mediated MG in seronegative patients with myasthenia-like symptoms but, due to the invasiveness of the muscle biopsy procedure, clustered AChR Abs should, if possible, be tested first.
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Affiliation(s)
- Atsushi Nagaoka
- Department of Clinical Neuroscience, Unit of Clinical Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki City, Japan.
| | - Akira Tsujino
- Department of Clinical Neuroscience, Unit of Clinical Medicine, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki City, Japan.
| | - Hirokazu Shiraishi
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan
| | - Tadashi Kanamoto
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan
| | - Tomoaki Shima
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan.
| | - Shunsuke Yoshimura
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan.
| | - Teiichiro Miyazaki
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan.
| | - Yohei Tateishi
- Department of Neurology and Strokology, Nagasaki University Hospital, Nagasaki City, Japan.
| | | | - Masakatsu Motomura
- Medical Electronic Course, Nagasaki Institute of Applied Science, Nagasaki City, Japan.
| | - Susan Maxwell
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
| | - Osamu Higuchi
- Department of Neurology, Nagasaki Kawatana Medical Center, Nagasaki, Japan.
| | - David Beeson
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
| | - Angela Vincent
- Nuffield Department of Clinical Neurosciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
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Shah SMI, Yasmin F, Memon RS, Jatoi NN, Savul IS, Kazmi S, Monawwer SA, Zafar MDB, Asghar MS, Tahir MJ, Lee KY. COVID-19 and myasthenia gravis: A review of neurological implications of the SARS-COV-2. Brain Behav 2022; 12:e2789. [PMID: 36306401 PMCID: PMC9759145 DOI: 10.1002/brb3.2789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 09/10/2022] [Accepted: 09/24/2022] [Indexed: 11/11/2022] Open
Abstract
INTRODUCTION This review highlights the potential mechanisms of neuromuscular manifestation of COVID-19, especially myasthenia gravis (MG). METHODS An extensive literature search was conducted by two independent investigators using PubMed/MEDLINE and Google Scholar from its inception to December 2020. RESULTS Exacerbations of clinical symptoms in patients of MG who were treated with some commonly used COVID-19 drugs has been reported, with updated recommendations of management of symptoms of neuromuscular disorders. Severe acute respiratory syndrome coronavirus 2 can induce the immune response to trigger autoimmune neurological disorders. CONCLUSIONS Further clinical studies are warranted to indicate and rather confirm if MG in the setting of COVID-19 can pre-existent subclinically or develop as a new-onset disease.
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Affiliation(s)
| | - Farah Yasmin
- Department of Internal Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | - Roha Saeed Memon
- Department of Internal Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | - Nadia Nazir Jatoi
- Department of Internal Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | - Ilma Saleh Savul
- Department of Internal Medicine, St. Joseph Medical Center, Houston, Texas, USA
| | - Sana Kazmi
- Department of Internal Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | | | - Muhammad Daim Bin Zafar
- Department of Internal Medicine, Dow Medical College, Dow University of Health Sciences, Karachi, Pakistan
| | | | | | - Ka Yiu Lee
- Swedish Winter Sports Research Centre, Department of Health Sciences, Mid Sweden University, Östersund, Sweden
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Point Counter-Point: Thymectomy in Ocular Myasthenia Gravis. J Neuroophthalmol 2022; 42:541-546. [PMID: 36394968 DOI: 10.1097/wno.0000000000001748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Schubert M, Pelz A, Trautmann G, Block K, Furlan S, Gutsmann M, Kohler S, Volpe P, Blottner D, Meisel A, Salanova M. Opposite Regulation of Homer Signal at the NMJ Postsynaptic Micro Domain between Slow- and Fast-Twitch Muscles in an Experimentally Induced Autoimmune Myasthenia Gravis (EAMG) Mouse Model. Int J Mol Sci 2022; 23:ijms232315052. [PMID: 36499379 PMCID: PMC9738765 DOI: 10.3390/ijms232315052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 11/17/2022] [Accepted: 11/26/2022] [Indexed: 12/03/2022] Open
Abstract
Accelerated postsynaptic remodelling and disturbance of neuromuscular transmission are common features of autoimmune neurodegenerative diseases. Homer protein isoform expression, crosslinking activity and neuromuscular subcellular localisation are studied in mouse hind limb muscles of an experimentally induced autoimmune model of Myasthenia Gravis (EAMG) and correlated to motor end plate integrity. Soleus (SOL), extensor digitorum longus (EDL) and gastrocnemius (GAS) skeletal muscles are investigated. nAChR membrane clusters were studied to monitor neuromuscular junction (NMJ) integrity. Fibre-type cross-sectional area (CSA) analysis is carried out in order to determine the extent of muscle atrophy. Our findings clearly showed that crosslinking activity of Homer long forms (Homer 1b/c and Homer2a/b) are decreased in slow-twitch and increased in fast-twitch muscle of EAMG whereas the short form of Homer that disrupts Homer crosslinking (Homer1a) is upregulated in slow-twitch muscle only. Densitometry analysis showed a 125% increase in Homer protein expression in EDL, and a 45% decrease in SOL of EAMG mice. In contrast, nAChR fluorescence pixel intensity decreased in endplates of EAMG mice, more distinct in type-I dominant SOL muscle. Morphometric CSA of EAMG vs. control (CTR) revealed a significant reduction in EDL but not in GAS and SOL. Taken together, these results indicate that postsynaptic Homer signalling is impaired in slow-twitch SOL muscle from EAMG mice and provide compelling evidence suggesting a functional coupling between Homer and nAChR, underscoring the key role of Homer in skeletal muscle neurophysiology.
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Affiliation(s)
- Martin Schubert
- Institute of Integrative Neuroanatomy, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10115 Berlin, Germany
| | - Andreas Pelz
- Department of Experimental Neurology, Charité—Universitätsmedizin Berlin, 10115 Berlin, Germany
| | - Gabor Trautmann
- Institute of Integrative Neuroanatomy, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10115 Berlin, Germany
| | - Katharina Block
- Center of Space Medicine Berlin, Neuromuscular Signaling and System, 10115 Berlin, Germany
| | - Sandra Furlan
- C.N.R. Institute of Neuroscience, 35131 Padova, Italy
| | - Martina Gutsmann
- Institute of Integrative Neuroanatomy, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10115 Berlin, Germany
| | - Siegfried Kohler
- Department of Experimental Neurology, Charité—Universitätsmedizin Berlin, 10115 Berlin, Germany
| | - Pompeo Volpe
- Department of Biomedical Sciences, University of Padova, 35122 Padova, Italy
| | - Dieter Blottner
- Institute of Integrative Neuroanatomy, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10115 Berlin, Germany
- Center of Space Medicine Berlin, Neuromuscular Signaling and System, 10115 Berlin, Germany
| | - Andreas Meisel
- Department of Experimental Neurology, Charité—Universitätsmedizin Berlin, 10115 Berlin, Germany
| | - Michele Salanova
- Institute of Integrative Neuroanatomy, Charité—Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, 10115 Berlin, Germany
- Center of Space Medicine Berlin, Neuromuscular Signaling and System, 10115 Berlin, Germany
- Correspondence: ; Tel.: +49-30-450528-354
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Yoshikawa H, Adachi Y, Nakamura Y, Kuriyama N, Murai H, Nomura Y, Sakai Y, Iwasa K, Furukawa Y, Kuwabara S, Matsui M. Two-step nationwide epidemiological survey of myasthenia gravis in Japan 2018. PLoS One 2022; 17:e0274161. [PMID: 36129914 PMCID: PMC9491589 DOI: 10.1371/journal.pone.0274161] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Accepted: 08/23/2022] [Indexed: 11/18/2022] Open
Abstract
Objective To study the updated prevalence and clinical features of myasthenia gravis (MG) in Japan during 2017. Methods We sent survey sheets to the randomly selected medical departments (number = 7,545). First, we asked the number of MG patients who visited medical departments from January 1, 2017, to December 31, 2017. Then, we sent the second survey sheet to the medical departments that answered the first survey to obtain the clinical information of patients who received MG diagnosis between January 1, 2015, and December 31, 2017. Results The received answer to the first survey were 2,708 (recovery rate: 35.9%). After all, the prevalence of the 100,000 population was estimated as 23.1 (95%CI: 20.5–25.6). As a result of the second survey, we obtained 1,464 case records. After checking the duplications and lacking data, we utilized 1,195 data for further analysis. The median [interquartile range (IQR)] from the onset age of total patients was 59 (43–70) years old. The male-female ratio was 1: 1.15. The onset age [median (IQR)] for female patients was 58 (40–72) years old, and that for male patients was 60 (49–69) years old (Wilcoxon-Mann-Whitney test, p = 0.0299). We divided patients into four categories: 1) anti-acetylcholine receptor antibody (AChRAb) (+) thymoma (Tm) (-), 2) AChRAb(+)Tm(+), 3) anti-muscle-specific kinase antibody (MuSKAb) (+), and AChRAb(-)MuSKAb(-) (double negative; DN). The onset age [median (IQR)] of AChRAb(+)Tm(-) was 64 (48–73) years old, and AChRb(+)Tm(+) was 55 (45–66), MuSKAb(+) was 49 (36–64), DN was 47 (35–60) year old. The multivariate logistic regression analysis using sex, initial symptoms, repetitive nerve stimulation test (RNST), and edrophonium test revealed that sex, ocular symptoms, bulbar symptoms, and RNST were factors to distinguish each category. The myasthenia gravis activities of daily living profile at the severest state were significantly higher in MuSKAb(+). MuSKAb(+) frequently received prednisolone, tacrolimus plasmapheresis, and intravenous immunoglobulin; however, they received less acetylcholine esterase inhibitor. 99.2% of AChRAb(+)Tm(+) and 15.4% of AChRAb(+)Tm(-) received thymectomy. MuSKAb(+) did not receive thymectomy, and only 5.7% of DN received thymectomy. The prognosis was favorable in all categories. Conclusion Our result revealed that the prevalence of Japanese MG doubled from the previous study using the same survey method in 2006. We also found that the onset age shifted to the elderly, and the male-female ratio reached almost even. Classification in four categories; AChRAb(+)Tm(-), AChRAb(+)Tm(+), MuSKAb(+), and DN, well describe the specific clinical features of each category and differences in therapeutic approaches.
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Affiliation(s)
- Hiroaki Yoshikawa
- Health Service Center, Kanazawa University, Kanazawa, Ishikawa, Japan
- * E-mail:
| | - Yumi Adachi
- Health Service Center, Kanazawa University, Kanazawa, Ishikawa, Japan
| | | | - Nagato Kuriyama
- Department of Epidemiology for Community Health and Medicine, Kyoto Prefectural University of Medicine, Kamigyo-Ku, Kyoto, Japan
| | - Hiroyuki Murai
- Department of Neurology, School of Medicine, International University of Health and Welfare, Narita, Chiba, Japan
| | - Yoshiko Nomura
- Yoshiko Nomura Neurological Clinic for Children, Bunkyo-Ku, Tokyo, Japan
| | - Yasunari Sakai
- Department of Pediatrics, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Fukuoka, Japan
| | - Kazuo Iwasa
- Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Yutaka Furukawa
- Department of Neurology and Neurobiology of Aging, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan
| | - Satoshi Kuwabara
- Department of Neurology, Graduate School of Medicine, Chiba University, Chiba, Chiba, Japan
| | - Makoto Matsui
- Department of Neurology, Kanazawa Medical University, Uchinada, Ishikawa, Japan
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Brates D, Harel D, Molfenter SM. Perception of Swallowing-Related Fatigue Among Older Adults. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2022; 65:2801-2814. [PMID: 35921661 DOI: 10.1044/2022_jslhr-22-00151] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
PURPOSE Although fatigue is recognized as clinically relevant to swallowing performance, its prevalence and significance in dysphagic and nondysphagic adults have not been sufficiently examined. In this study, an online survey was used to examine swallowing- and eating-related fatigue (SERF) symptoms, the relationship between perceived SERF and other dysphagia-related health outcomes, and whether perceived SERF predicts risk for dysphagia or malnutrition. METHOD An online survey of older adults (aged 60 years or older) was conducted. A novel 12-item scale was developed to capture perceived SERF. Previously validated scales were used to measure dysphagia risk, sarcopenia, general fatigue, malnutrition risk, and quality of life. Logistic regression was used to examine whether SERF predicted risk for dysphagia and/or malnutrition. RESULTS Complete responses were collected from 417 community-dwelling adults (M age = 70.6 years, SD = 4.9; 263 women); 75% (n = 312) reported at least some degree of SERF. SERF was significantly correlated with dysphagia risk, sarcopenia, general fatigue, malnutrition risk, and quality of life. SERF was a significant predictor of dysphagia risk while controlling for age, gender, and other health outcomes (odds ratio [OR] = 1.2, 95% confidence interval [CI; 1.16, 1.27], p < .001). For every unit increase in SERF score, the odds of being at risk for dysphagia were associated with an increase of 22%. Significant predictors for malnutrition risk included SERF (OR = 0.94, 95% CI [0.91, 0.98]), general fatigue (OR = 0.95, 95% CI [0.92, 0.99]), and quality of life (OR = 1.04, 95% CI [1.0, 1.1]). CONCLUSIONS Fatigue during swallowing and mealtimes is experienced by community-dwelling older adults and predicted dysphagia risk and malnutrition risk. Further research is needed to refine and validate a patient-reported outcome measure for SERF and examine the effects of fatigue on swallowing function and physiology under imaging. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.20405835.
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Affiliation(s)
- Danielle Brates
- Department of Communicative Sciences and Disorders, New York University, NY
| | - Daphna Harel
- Department of Applied Statistics, Social Science, and Humanities, New York University, NY
| | - Sonja M Molfenter
- Department of Communicative Sciences and Disorders, New York University, NY
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Lazaridis K, Fernandez-Santoscoy M, Baltatzidou V, Andersson JO, Christison R, Grünberg J, Tzartos S, Löwenadler B, Fribert C. A Recombinant Acetylcholine Receptor α1 Subunit Extracellular Domain Is a Promising New Drug Candidate for Treatment Of Myasthenia Gravis. Front Immunol 2022; 13:809106. [PMID: 35720339 PMCID: PMC9204200 DOI: 10.3389/fimmu.2022.809106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Accepted: 04/21/2022] [Indexed: 12/03/2022] Open
Abstract
Background and Aims Myasthenia gravis (MG) is a T-cell dependent antibody-mediated autoimmune disease in which the nicotinic acetylcholine receptor (AChR) is the major autoantigen, comprising several T and B cell auto-epitopes. We hypothesized that an efficacious drug candidate for antigen-specific therapy in MG should comprise a broad range of these auto-epitopes and be administered in a noninflammatory and tolerogenic context. Methods We used a soluble mutated form of the extracellular domain of the α1 chain of the AChR (α1-ECDm), which represents the major portion of auto-epitopes involved in MG, and investigated, in a well-characterized rat model of experimental autoimmune myasthenia gravis (EAMG) whether its intravenous administration could safely and efficiently treat the autoimmune disease. Results We demonstrated that intravenous administration of α1-ECDm abrogates established EAMG, in a dose and time dependent manner, as assessed by clinical symptoms, body weight, and compound muscle action potential (CMAP) decrement. Importantly, the effect was more pronounced compared to drugs representing current standard of care for MG. The protein had a short plasma half-life, most of what could be recovered was sequestered in the liver, kidneys and spleen. Further, we did not observe any signs of toxicity or intolerability in animals treated with α1-ECDm. Conclusion We conclude that intravenous treatment with α1-ECDm is safe and effective in suppressing EAMG. α1-ECDm is in preclinical development as a promising new drug candidate for MG.
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Affiliation(s)
| | | | | | | | | | | | - Socrates Tzartos
- Department of Neurobiology, Hellenic Pasteur Institute, Athens, Greece.,Tzartos NeuroDiagnostics, Athens, Greece
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Kang SA, Sweeney M, Govindarajan R. Academic and Employment Status in Patients With Generalized Myasthenia Gravis Treated With Eculizumab: A Case Series. J Clin Neuromuscul Dis 2022; 23:210-218. [PMID: 35608645 PMCID: PMC9126260 DOI: 10.1097/cnd.0000000000000391] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To evaluate the impact of treatment with eculizumab, a terminal complement inhibitor, on academic and employment status in patients with refractory generalized myasthenia gravis (MG). METHODS Case review of 7 US patients. RESULTS Six patients were aged ≤65 years; one was a full-time student and the remainder were in employment before MG diagnosis. After diagnosis, all patients gave up work (n = 3) or reduced their study/working hours (n = 4). In the 12 months after eculizumab initiation, patients who had stopped work resumed working in some capacity, whereas those who had changed their work/study hours returned to their original work/study pattern. Patients also experienced a reduction in the number of MG exacerbations, and a clinically significant improvement in MG-Activities of Daily Living scores, and were able to reduce other MG medications. CONCLUSIONS These results suggest that treatment with eculizumab may help maintain education/employment activity in patients with refractory generalized MG.
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Affiliation(s)
- Seung Ah Kang
- Department of Neurology, University of Missouri Health Care, Columbia, MO
| | - Megan Sweeney
- Department of Neurology, University of Missouri Health Care, Columbia, MO
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Vu T, Meisel A, Mantegazza R, Annane D, Katsuno M, Aguzzi R, Enayetallah A, Beasley KN, Rampal N, Howard JF. Terminal Complement Inhibitor Ravulizumab in Generalized Myasthenia Gravis. NEJM EVIDENCE 2022; 1:EVIDoa2100066. [PMID: 38319212 DOI: 10.1056/evidoa2100066] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2024]
Abstract
BACKGROUND: Generalized myasthenia gravis (gMG) is a rare, chronic, and debilitating autoimmune disease. Activation of the complement system by autoantibodies against the postsynaptic acetylcholine receptor (AChR) leads to destruction of the postsynaptic membrane and disruption of neuromuscular transmission. This trial evaluated ravulizumab, a long-acting inhibitor of terminal complement protein C5, as a treatment for gMG. METHODS: In this randomized, double-blind, placebo-controlled, multinational trial, we randomly assigned (1:1) patients with anti-AChR antibody-positive gMG to intravenous ravulizumab or placebo for 26 weeks. Patients received a loading dose on day 1, followed by maintenance doses on day 15 and every 8 weeks thereafter. The primary end point and first secondary end point (change from baseline to week 26 in patient-reported Myasthenia Gravis–Activities of Daily Living [MG-ADL] scale and clinician-reported Quantitative Myasthenia Gravis [QMG] total scores, respectively) were compared between the ravulizumab- and placebo-treated groups. RESULTS: In total, 175 patients were enrolled. Ravulizumab significantly increased the magnitude of mean changes from baseline to week 26 versus placebo in MG-ADL (−3.1 vs. −1.4; P<0.001) and QMG (−2.8 vs. −0.8; P<0.001) total scores. Improvements in both measures occurred within 1 week of ravulizumab initiation and were sustained through week 26. QMG total scores improved by 5 points or more in a significantly greater proportion of ravulizumab-treated patients than of those receiving placebo (30.0% vs. 11.3%; P=0.005). No notable differences in adverse events were observed. CONCLUSIONS: Ravulizumab demonstrated rapid and sustained improvements in both patient- and clinician-reported outcomes and had a side effect and adverse-event profile that did not limit treatment in adults with anti-AChR antibody-positive gMG. (Funded by Alexion, AstraZeneca Rare Disease; ClinicalTrials.gov number, NCT03920293; EudraCT number, 2018-003243-39.)
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Affiliation(s)
- Tuan Vu
- University of South Florida Morsani College of Medicine, Tampa
| | | | - Renato Mantegazza
- Fondazione Istituto di Ricovero e Cura a Carattere Scientifico Istituto Neurologico Carlo Besta, Milan
| | - Djillali Annane
- Hôpital Raymond Poincaré, University of Versailles, Garches, France
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Dalakas MC. Autoimmune Neurological Disorders with IgG4 Antibodies: a Distinct Disease Spectrum with Unique IgG4 Functions Responding to Anti-B Cell Therapies. Neurotherapeutics 2022; 19:741-752. [PMID: 35290608 PMCID: PMC9294117 DOI: 10.1007/s13311-022-01210-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/18/2022] [Indexed: 11/26/2022] Open
Abstract
The main IgG4 antibody-mediated neurological disorders (IgG4-ND) include MuSK myasthenia; CIDP with nodal/paranodal antibodies to Neurofascin-155, contactin-1/caspr-1, or pan-neurofascins; anti-LGI1 and CASPR2-associated limbic encephalitis, Morvan syndrome, or neuromyotonia; and several cases of the anti-IgLON5 and anti-DPPX-spectrum CNS diseases. The paper is centered on the clinical spectrum of IgG4-ND and their immunopathogenesis highlighting the unique functional effects of the IgG4 subclass compared to IgG1-3 antibody subclasses. The IgG4 antibodies exert pathogenic effects on their targeted antigens by blocking enzymatic activity or disrupting protein-protein interactions affecting signal transduction pathways, but not by activating complement, binding to inhibitory FcγRIIb receptor or engaging in cross-linking of the targeted antigen with immune complex formation as the IgG1-IgG3 antibody subclasses do. IgG4 can even inhibit the classical complement pathway by affecting the affinity of IgG1-2 subclasses to C1q binding. Because the IgG4 antibodies do not trigger inflammatory processes or complement-mediated immune responses, the conventional anti-inflammatory therapies, especially with IVIg, immunosuppressants, and plasmapheresis, are ineffective or not sufficiently effective in inducing long-term remissions. In contrast, aiming at the activated plasmablasts connected with IgG4 antibody production is a meaningful therapeutic target in IgG4-ND. Indeed, data from large series of patients with MuSK myasthenia, CIDP with nodal/paranodal antibodies, and anti-LGI1 and CASPR2-associated syndromes indicate that B cell depletion therapy with rituximab exerts long-lasting clinical remissions by targeting memory B cells and IgG4-producing CD20-positive short-lived plasma cells. Because IgG4 antibody titers seem reduced in remissions and increased in exacerbation, they may serve as potential biomarkers of treatment response supporting further the pathogenic role of self-reacting B cells. Controlled trials are needed in IgG4-ND not only with rituximab but also with the other anti-B cell agents that target CD19/20, especially those like obexelimab and obinutuzumab, that concurrently activate the inhibitory FcγRIIb receptors which have low binding affinity to IgG4, exerting a more prolonged anti-B cell action affecting also antigen presentation and cytotoxic T cells. Antibody therapies targeting FcRn, testing those anti-FcRn inhibitors that effectively catabolize the IgG4 antibody subclass, may be especially promising.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.
- Neuroimmunology Unit National and Kapodistrian University of Athens Medical School, Athens, Greece.
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Vyas S, Bansal A, Murugan N, Bhalla AS, Naranje P, Manchanda S. Hypersensitivity reactions and the respiratory system: Imaging based review. Curr Probl Diagn Radiol 2022; 52:56-65. [DOI: 10.1067/j.cpradiol.2022.04.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2022] [Revised: 03/24/2022] [Accepted: 04/18/2022] [Indexed: 11/22/2022]
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Spontaneous Remission in Juvenile Myasthenia Gravis: A cohort of 13 cases and review of the literature. Neuromuscul Disord 2022; 32:213-219. [DOI: 10.1016/j.nmd.2021.11.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2021] [Revised: 11/28/2021] [Accepted: 11/29/2021] [Indexed: 11/30/2022]
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Meng X, Zeng Z, Wang Y, Guo S, Wang C, Wang B, Guo S. Efficacy and Safety of Low-Dose Rituximab in Anti-MuSK Myasthenia Gravis Patients: A Retrospective Study. Neuropsychiatr Dis Treat 2022; 18:953-964. [PMID: 35535211 PMCID: PMC9078430 DOI: 10.2147/ndt.s358851] [Citation(s) in RCA: 2] [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: 01/18/2022] [Accepted: 04/21/2022] [Indexed: 01/19/2023] Open
Abstract
PURPOSE To evaluate the efficacy and safety of low dosages of rituximab (RTX) in the treatment of MuSK-antibody-positive MG patients. PATIENTS AND METHODS We retrospectively analyzed the data of MuSK-antibody-positive MG patients who were treated with low dosages of RTX from January 2018 to October 2021. The long-term treatment response to RTX was assessed by Myasthenia Gravis Foundation of America (MGFA) post-interventional status (PIS), Myasthenia Gravis Status and Treatment Intensity (MGSTI), dosage of steroid, MG-related activities of daily living (MG-ADL) and myasthenic muscle score (MMS) at the end of follow-up. RESULTS Clinical improvement was observed in all eight patients with follow-up for 8 to 29 months after treatment. At the last visit, complete stable remission had been achieved in one patient, pharmacologic remission in three patients, minimal manifestations status in three patients and improved in one patient based on the MGFA-PIS criteria. MGSTI level 2 or better had been reached in six (75%) patients at the last visit. The steroid dosage decreased from 60 mg at baseline to 15 mg at the last follow-up (p = 0.011). The average MG-ADL score decreased from 11 (range 7 to 15) to 0 (range 0 to 3; p = 0.011), and the MMS improved from 38.5 (range 24 to 60) to 100 (range 90 to 100; p = 0.012). These differences were all statistically significant. During RTX treatment and subsequent follow-up, 1 patient reported minor post-infusion malaise. CONCLUSION Low-dose RTX is effective and safe for treating anti-MuSK antibody positive MG patients. A long-term response is observed after treatment. Larger prospective studies are required to provide further evidence.
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Affiliation(s)
- Xin Meng
- Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, People's Republic of China
| | - Ziling Zeng
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, People's Republic of China
| | - Yunda Wang
- Department of Neurosurgery, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, People's Republic of China
| | - Shuai Guo
- Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, People's Republic of China
| | - Chunjuan Wang
- Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, People's Republic of China
| | - Baojie Wang
- Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, People's Republic of China
| | - Shougang Guo
- Department of Neurology, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan, Shandong, People's Republic of China.,Department of Neurology, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, People's Republic of China
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Dalakas MC. IgG4-Mediated Neurologic Autoimmunities: Understanding the Pathogenicity of IgG4, Ineffectiveness of IVIg, and Long-Lasting Benefits of Anti-B Cell Therapies. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2022; 9:9/1/e1116. [PMID: 34845096 PMCID: PMC8630661 DOI: 10.1212/nxi.0000000000001116] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/23/2021] [Accepted: 10/08/2021] [Indexed: 12/15/2022]
Abstract
BACKGROUND AND OBJECTIVES Describe the unique functions of immunoglobulin G4 (IgG4) in IgG4-neurologic disorders (IgG4-ND) and explain why, in contrast to their IgG1-counterparts, they respond poorly to intravenous immune globulin (IVIg) but effectively to anti-B cell therapies. METHODS The IgG4 structure and isotype switch, B cells and plasmablasts relevant to IgG4 production, and IgG4-induced disruption of the targeted antigens are reviewed and compared with IgG1-mediated autoimmune ND, where IVIg inhibits IgG1-triggered inflammatory effects. RESULTS The main IgG4-ND include muscle-specific kinase myasthenia; nodal/paranodal chronic inflammatory demyelinating polyradiculoneuropathy with antibodies to neurofascin-155, contactin-1/caspr-1, or pan-neurofascins; antileucine-rich, glioma-inactivated-1 and contactin-associated protein-like 2 associated-limbic encephalitis, Morvan syndrome, or neuromyotonia; and anti-IgLON5 disorder. The IgG4, because of its unique structural features in the hinge region, has noninflammatory properties being functionally monovalent and bispecific, unable to engage in cross-linking and internalization of the targeted antigen. In contrast to IgG1 subclass which is bivalent and monospecific, IgG4 does not activate complement and cannot bind to inhibitory Fcγ receptor (FcγRIIb) to activate cellular and complement-mediated immune responses, the key functions inhibited by IVIg. Because IVIg contains only 0.7%-2.6% IgG4, its idiotypes are of IgG1 subclass and cannot effectively neutralize IgG4 or sufficiently enhance IgG4 catabolism by saturating FcRn. In contrast, rituximab, by targeting memory B cells and IgG4-producing CD20-positive short-lived plasma cells, induces long-lasting clinical benefits. DISCUSSION Rituximab is the preferred treatment in IgG4-ND patients with severe disease by effectively targeting the production of pathogenic IgG-4 antibodies. In contrast, IVIG is ineffective because it inhibits immunoinflammatory functions irrelevant to the mechanistic effects of IgG4 and contains IgG-1 idiotypes that cannot sufficiently neutralize or possibly catabolize IgG4. Controlled studies with anti-CD19/20 monoclonals that also activate FcγRIIb may be more promising in treating IgG4-ND.
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Affiliation(s)
- Marinos C Dalakas
- From Thomas Jefferson University, Philadelphia, PA; and the University of Athens Medical School, Greece.
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Gomathy SB, Agarwal A, Vishnu VY. Molecular Therapy in Myasthenia Gravis. Neurology 2022. [DOI: 10.17925/usn.2022.18.1.49] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disorder caused by antibodies that act against the myoneural junction. Conventional immunosuppressants such as corticosteroids, azathioprine and mycophenolate are associated with long-term side effects and many patients do not achieve remission and may become refractory. Thus, there is an unmet need for target-specific therapies that act faster, have fewer side effects and lead to stable disease remission. However, many of the novel therapeutic agents being described are not meeting their primary endpoints. We reviewed the current status of novel immunotherapies for MG, their mechanisms of action, along with the side effect profiles. Fast onset of action, sustained disease remission and relatively low frequency of side effects of the new agents are attractive. However, the unknown long-term safety and high cost are precluding factors. Better preclinical studies and more randomized trials are needed before novel agents are routinely employed.
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Quigley R, Koenig ZA, Schick S, Miller E. A Complicated Case of Postpartum Myasthenic Crisis. Cureus 2021; 13:e20247. [PMID: 35018255 PMCID: PMC8737072 DOI: 10.7759/cureus.20247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/07/2021] [Indexed: 11/13/2022] Open
Abstract
Myasthenia gravis (MG) is the most common autoimmune disorder affecting the neuromuscular junction (NMJ) of voluntary skeletal muscle. This disease is characterized by ptosis, diplopia, facial muscle weakness, bulbar muscle involvement including dysphagia and difficulty chewing, dysarthria, hypophonia, respiratory muscle fatigue, and sometimes generalized weakness. A myasthenic crisis (MC) is a complication of MG. MC is defined as severe worsening of respiratory function necessitating the need for mechanical ventilation. Precipitating factors include infection, certain drugs, pregnancy, childbirth, surgery, discontinuation of medical therapy, or even spontaneously with no inciting event. Here we present a complicated case of a 24-year-old patient with a long history of controlled who encounters many events that lead to an MC necessitating mechanical intubation, plasmapheresis, and high dose immunosuppressive therapy. She recently gave birth to a child, had an occult perforated appendicitis with multiple abscesses needing emergent exploratory laparotomy, and had an overlying COVID-19 infection. The complexity of this disease and its complications warrants careful consideration by physicians in any branch of specialty.
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Affiliation(s)
- Ryan Quigley
- Department of Medicine, West Virginia University, Morgantown, USA
| | - Zachary A Koenig
- Department of Medicine, West Virginia University, Morgantown, USA
| | - Samuel Schick
- Department of Medicine, West Virginia University, Morgantown, USA
| | - Erin Miller
- Department of Obstetrics and Gynecology, West Virginia University, Martinsburg, USA
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Monteleone JPR, Gao X, Kleijn HJ, Bellanti F, Pelto R. Eculizumab Pharmacokinetics and Pharmacodynamics in Patients With Generalized Myasthenia Gravis. Front Neurol 2021; 12:696385. [PMID: 34795626 PMCID: PMC8594444 DOI: 10.3389/fneur.2021.696385] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Accepted: 08/20/2021] [Indexed: 11/17/2022] Open
Abstract
Objective: To investigate the pharmacokinetics, pharmacodynamics, and exposure-response of the approved 900/1,200 mg dosing regimen for the terminal complement component 5 (C5) inhibitor eculizumab in patients with generalized myasthenia gravis (gMG). Methods: The analysis used data from 62 patients aged ≥ 18 years with anti-acetylcholine receptor (AChR) antibody-positive refractory gMG who received eculizumab during the REGAIN study (ClinicalTrials.gov: NCT01997229). One- and two-compartment population-pharmacokinetic models were evaluated, and the impact of covariates on pharmacokinetic parameters was assessed. Relationships between eculizumab exposure and free C5 concentration, in vitro hemolytic activity, clinical response, and tolerability were characterized. Results: Steady-state serum eculizumab concentrations were achieved by Week 4 and were sustained throughout the 26-week treatment period. The eculizumab pharmacokinetic data were well-described by a two-compartment model with first-order elimination, including effects of body weight on pharmacokinetic parameters and plasma-exchange events on clearance. Complete inhibition of terminal complement was achieved in nearly all patients at the time of trough and peak eculizumab concentrations at all post-dose timepoints assessed (free C5 < 0.5 μg/ml in 92% of patients; in vitro hemolysis < 20% in 87% of patients). Serum eculizumab concentrations of ≥116 μg/ml achieved free C5 concentrations of < 0.5 μg/ml. Clinical efficacy and tolerability were consistent across the eculizumab exposure range. Conclusions: Rigorous, quantitative, model-based exposure-response analysis of serum eculizumab concentration and response data demonstrated that the approved eculizumab dosing (900/1,200 mg) for adults with anti-AChR antibody-positive refractory gMG rapidly achieved complete inhibition of terminal complement activation and provided sustained clinical efficacy across the eculizumab exposure range.
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Affiliation(s)
- Jonathan P. R. Monteleone
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
| | - Xiang Gao
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
| | | | | | - Ryan Pelto
- Department of Pharmacometrics, PK/PD M&S, Clinical Development and Translational Sciences, Alexion Pharmaceuticals Inc., Boston, MA, United States
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Dalakas MC. Update on Intravenous Immunoglobulin in Neurology: Modulating Neuro-autoimmunity, Evolving Factors on Efficacy and Dosing and Challenges on Stopping Chronic IVIg Therapy. Neurotherapeutics 2021; 18:2397-2418. [PMID: 34766257 PMCID: PMC8585501 DOI: 10.1007/s13311-021-01108-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/11/2021] [Indexed: 02/07/2023] Open
Abstract
In the last 25 years, intravenous immunoglobulin (IVIg) has had a major impact in the successful treatment of previously untreatable or poorly controlled autoimmune neurological disorders. Derived from thousands of healthy donors, IVIg contains IgG1 isotypes of idiotypic antibodies that have the potential to bind pathogenic autoantibodies or cross-react with various antigenic peptides, including proteins conserved among the "common cold"-pre-pandemic coronaviruses; as a result, after IVIg infusions, some of the patients' sera may transiently become positive for various neuronal antibodies, even for anti-SARS-CoV-2, necessitating caution in separating antibodies derived from the infused IVIg or acquired humoral immunity. IVIg exerts multiple effects on the immunoregulatory network by variably affecting autoantibodies, complement activation, FcRn saturation, FcγRIIb receptors, cytokines, and inflammatory mediators. Based on randomized controlled trials, IVIg is approved for the treatment of GBS, CIDP, MMN and dermatomyositis; has been effective in, myasthenia gravis exacerbations, and stiff-person syndrome; and exhibits convincing efficacy in autoimmune epilepsy, neuromyelitis, and autoimmune encephalitis. Recent evidence suggests that polymorphisms in the genes encoding FcRn and FcγRIIB may influence the catabolism of infused IgG or its anti-inflammatory effects, impacting on individualized dosing or efficacy. For chronic maintenance therapy, IVIg and subcutaneous IgG are effective in controlled studies only in CIDP and MMN preventing relapses and axonal loss up to 48 weeks; in practice, however, IVIg is continuously used for years in all the aforementioned neurological conditions, like is a "forever necessary therapy" for maintaining stability, generating challenges on when and how to stop it. Because about 35-40% of patients on chronic therapy do not exhibit objective neurological signs of worsening after stopping IVIg but express subjective symptoms of fatigue, pains, spasms, or a feeling of generalized weakness, a conditioning effect combined with fear that discontinuing chronic therapy may destabilize a multi-year stability status is likely. The dilemmas of continuing chronic therapy, the importance of adjusting dosing and scheduling or periodically stopping IVIg to objectively assess necessity, and concerns in accurately interpreting IVIg-dependency are discussed. Finally, the merit of subcutaneous IgG, the ineffectiveness of IVIg in IgG4-neurological autoimmunities, and genetic factors affecting IVIg dosing and efficacy are addressed.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, USA.
- Neuroimmunology Unit, Dept. of Pathophysiology, National and Kapodistrian University of Athens Medical School, Athens, Greece.
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Clinical Predictors of Prolonged Hospital Stay in Patients with Myasthenia Gravis: A Study Using Machine Learning Algorithms. J Clin Med 2021; 10:jcm10194393. [PMID: 34640412 PMCID: PMC8509494 DOI: 10.3390/jcm10194393] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2021] [Revised: 09/22/2021] [Accepted: 09/24/2021] [Indexed: 01/03/2023] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disorder that causes muscle weakness. Although the management is well established, some patients are refractory and require prolonged hospitalization. Our study is aimed to identify the important factors that predict the duration of hospitalization in patients with MG by using machine learning methods. A total of 21 factors were chosen for machine learning analyses. We retrospectively reviewed the data of patients with MG who were admitted to hospital. Five machine learning methods, including stochastic gradient boosting (SGB), least absolute shrinkage and selection operator (Lasso), ridge regression (Ridge), eXtreme gradient boosting (XGboost), and gradient boosting with categorical features support (Catboost), were used to construct models for identify the important factors affecting the duration of hospital stay. A total of 232 data points of 204 hospitalized MG patients admitted were enrolled into the study. The MGFA classification, treatment of high-dose intravenous corticosteroid, age at admission, treatment with intravenous immunoglobulins, and thymoma were the top five significant variables affecting prolonged hospitalization. Our findings from machine learning will provide physicians with information to evaluate the potential risk of MG patients having prolonged hospital stay. The use of high-dose corticosteroids is associated with prolonged hospital stay and to be used cautiously in MG patients.
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46
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Sindhu RK, Madaan P, Chandel P, Akter R, Adilakshmi G, Rahman MH. Therapeutic Approaches for the Management of Autoimmune Disorders via Gene Therapy: Prospects, Challenges, and Opportunities. Curr Gene Ther 2021; 22:245-261. [PMID: 34530709 DOI: 10.2174/1566523221666210916113609] [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: 01/26/2021] [Revised: 07/05/2021] [Accepted: 06/24/2021] [Indexed: 11/22/2022]
Abstract
BACKGROUND Autoimmune diseases are the diseases that result due to the overactive immune response, and comprise systemic autoimmune diseases like rheumatoid arthritis (RA), sjӧgren's syndrome (SS), and organ-specific autoimmune diseases like type-1 diabetes mellitus (T1DM), myasthenia gravis (MG), and inflammatory bowel disease (IBD). Currently, there is no long-term cure; but, several treatments exist which retard the evolution of the disease, embracing gene therapy, which has been scrutinized to hold immense aptitude for the management of autoimmune diseases. OBJECTIVE The review highlights the pathogenic mechanisms and genes liable for the development of autoimmune diseases, namely T1DM, type-2 diabetes mellitus (T2DM), RA, SS, IBD, and MG. Furthermore, the review focuses on investigating the outcomes of delivering the corrective genes with their specific viral vectors in various animal models experiencing these diseases to determine the effectiveness of gene therapy. METHODS Numerous review and research articles emphasizing the tremendous potential of gene therapy in the management of autoimmune diseases were procured from PubMed, MEDLINE, Frontier, and other databases and thoroughly studied for writing this review article. RESULTS The various animal models that experienced treatment with gene therapy have displayed regulation in the levels of proinflammatory cytokines, infiltration of lymphocytes, manifestations associated with autoimmune diseases, and maintained equilibrium in the immune response, thereby hinder the progression of autoimmune diseases. CONCLUSION Gene therapy has revealed prodigious aptitude in the management of autoimmune diseases in various animal studies, but further investigation is essential to combat the limitations associated with it and before employing it on humans.
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Affiliation(s)
- Rakesh K Sindhu
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Piyush Madaan
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Parteek Chandel
- Chitkara College of Pharmacy, Chitkara University, Punjab. India
| | - Rokeya Akter
- Department of Pharmacy, Jagannath University, Sadarghat, Dhaka-1100. Bangladesh
| | - G Adilakshmi
- Department of PhysicxVikramaSimahpuri University, P.G. Centre, kavil-524201, Andhra Pradesh. India
| | - Md Habibur Rahman
- Department of Pharmacy, Southeast University, Banani, Dhaka-1213. Bangladesh
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Evoli A, Spagni G, Monte G, Damato V. Heterogeneity in myasthenia gravis: considerations for disease management. Expert Rev Clin Immunol 2021; 17:761-771. [PMID: 34043932 DOI: 10.1080/1744666x.2021.1936500] [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: 02/06/2023]
Abstract
Introduction: Myasthenia gravis is a rare disease of the neuromuscular junction and a prototype of B cell-driven immunopathology. Pathogenic antibodies target post-synaptic transmembrane proteins, most commonly the nicotinic acetylcholine receptor and the muscle-specific tyrosine kinase, inducing end-plate alterations and neuromuscular transmission impairment. Several clinical subtypes are distinct on the basis of associated antibodies, age at symptom onset, thymus pathology, genetic factors, and weakness distribution. These subtypes have distinct pathogenesis that can account for different responses to treatment. Conventional therapy is based on the use of symptomatic agents, steroids, immunosuppressants and thymectomy. Of late, biologics have emerged as effective therapeutic options.Areas covered: In this review, we will discuss the management of myasthenia gravis in relation to its phenotypic and biological heterogeneity, in the light of recent advances in the disease immunopathology, new diagnostic tools, and results of clinical trialsExpert opinion: Clinical management is shaped on serological subtype, and patient age at onset, lifestyle and comorbidities, balancing therapeutic needs and safety. Although reliable biomarkers predictive of clinical and biologic outcome are still lacking, recent developments promise a more effective and safe treatment. Disease subtyping according to serological testing and immunopathology is crucial to the appropriateness of clinical management.
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Affiliation(s)
- Amelia Evoli
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy.,Unità Operativa Complessa di Neurologia, Fondazione Policlinico Universitario "A. Gemelli" IRCCS, Rome, Italy
| | - Gregorio Spagni
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Gabriele Monte
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
| | - Valentina Damato
- Dipartimento di Neuroscienze, Università Cattolica Del Sacro Cuore, Rome, Italy
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Hui T, Jing H, Lai X. Neuromuscular junction-specific genes screening by deep RNA-seq analysis. Cell Biosci 2021; 11:81. [PMID: 33933147 PMCID: PMC8088568 DOI: 10.1186/s13578-021-00590-9] [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: 03/15/2021] [Accepted: 04/17/2021] [Indexed: 01/17/2023] Open
Abstract
Background Neuromuscular junctions (NMJs) are chemical synapses formed between motor neurons and skeletal muscle fibers and are essential for controlling muscle contraction. NMJ dysfunction causes motor disorders, muscle wasting, and even breathing difficulties. Increasing evidence suggests that many NMJ disorders are closely related to alterations in specific gene products that are highly concentrated in the synaptic region of the muscle. However, many of these proteins are still undiscovered. Thus, screening for NMJ-specific proteins is essential for studying NMJ and the pathogenesis of NMJ diseases. Results In this study, synaptic regions (SRs) and nonsynaptic regions (NSRs) of diaphragm samples from newborn (P0) and adult (3-month-old) mice were used for RNA-seq. A total of 92 and 182 genes were identified as differentially expressed between the SR and NSR in newborn and adult mice, respectively. Meanwhile, a total of 1563 genes were identified as differentially expressed between the newborn SR and adult SR. Gene Ontology (GO) enrichment analyses, Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis and gene set enrichment analysis (GSEA) of the DEGs were performed. Protein–protein interaction (PPI) networks were constructed using STRING and Cytoscape. Further analysis identified some novel proteins and pathways that may be important for NMJ development, maintenance and maturation. Specifically, Sv2b, Ptgir, Gabrb3, P2rx3, Dlgap1 and Rims1 may play roles in NMJ development. Hcn1 may localize to the muscle membrane to regulate NMJ maintenance. Trim63, Fbxo32 and several Asb family proteins may regulate muscle developmental-related processes. Conclusion Here, we present a complete dataset describing the spatiotemporal transcriptome changes in synaptic genes and important synaptic pathways. The neuronal projection-related pathway, ion channel activity and neuroactive ligand-receptor interaction pathway are important for NMJ development. The myelination and voltage-gated ion channel activity pathway may be important for NMJ maintenance. These data will facilitate the understanding of the molecular mechanisms underlying the development and maintenance of NMJ and the pathogenesis of NMJ disorders.
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Affiliation(s)
- Tiankun Hui
- School of Life Science, Nanchang University, Nanchang, Jiangxi, China.,Laboratory of Synaptic Development and Plasticity, Institute of Life Science, Nanchang University, Nanchang, Jiangxi, China
| | - Hongyang Jing
- School of Life Science, Nanchang University, Nanchang, Jiangxi, China.,Laboratory of Synaptic Development and Plasticity, Institute of Life Science, Nanchang University, Nanchang, Jiangxi, China
| | - Xinsheng Lai
- School of Life Science, Nanchang University, Nanchang, Jiangxi, China. .,Laboratory of Synaptic Development and Plasticity, Institute of Life Science, Nanchang University, Nanchang, Jiangxi, China.
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Fuertes-Alvarez S, Izeta A. Terminal Schwann Cell Aging: Implications for Age-Associated Neuromuscular Dysfunction. Aging Dis 2021; 12:494-514. [PMID: 33815879 PMCID: PMC7990373 DOI: 10.14336/ad.2020.0708] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 07/08/2020] [Indexed: 12/11/2022] Open
Abstract
Action potential is transmitted to muscle fibers through specialized synaptic interfaces called neuromuscular junctions (NMJs). These structures are capped by terminal Schwann cells (tSCs), which play essential roles during formation and maintenance of the NMJ. tSCs are implicated in the correct communication between nerves and muscles, and in reinnervation upon injury. During aging, loss of muscle mass and strength (sarcopenia and dynapenia) are due, at least in part, to the progressive loss of contacts between muscle fibers and nerves. Despite the important role of tSCs in NMJ function, very little is known on their implication in the NMJ-aging process and in age-associated denervation. This review summarizes the current knowledge about the implication of tSCs in the age-associated degeneration of NMJs. We also speculate on the possible mechanisms underlying the observed phenotypes.
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Affiliation(s)
- Sandra Fuertes-Alvarez
- 1Biodonostia, Tissue Engineering Group, Paseo Dr. Begiristain, s/n, San Sebastian 20014, Spain
| | - Ander Izeta
- 1Biodonostia, Tissue Engineering Group, Paseo Dr. Begiristain, s/n, San Sebastian 20014, Spain.,2Tecnun-University of Navarra, School of Engineering, Department of Biomedical Engineering and Science, Paseo Mikeletegi, 48, San Sebastian 20009, Spain
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López-Viñas L, Rocío-Martín E, Delis-Gómez S, Wix-Ramos R. Myasthenia Gravis Related to Small Cell Lung Carcinoma. Cureus 2021; 13:e13889. [PMID: 33880245 PMCID: PMC8046688 DOI: 10.7759/cureus.13889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Myasthenia gravis is a neuromuscular disease that causes weakness in skeletal muscles because of the presence of acetylcholine receptor antibodies. These antibodies produce a compromise in the end-plate potential, reducing the safety factor for effective synaptic transmission. Clinically, this manifests as muscle weakness and, in severe cases, respiratory failure. There is widespread knowledge about the association between small cell lung carcinoma and Lambert- Eaton myasthenic syndrome, but not with other neuromuscular disorders, such as myasthenia gravis. We present a patient with small cell lung carcinoma who presented weakness affecting the proximal muscles over the last three years, and electromyography findings suggesting myasthenia gravis. After this electrodiagnosis, analytical tests showed an increase in anti-acetylcholine receptor antibodies. Given these findings, we can affirm that neurophysiological tests provide a significant value in diagnosing myasthenia gravis, as anti-acetylcholine receptor antibodies were negative at the moment of the electromyography’s performance. Likewise, it is essential to consider a paraneoplastic syndrome in this type of carcinoma.
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Affiliation(s)
- Laura López-Viñas
- Clinical Neurophysiology Department, Fundación Jiménez Díaz University Hospital, Madrid, ESP
| | | | | | - Rybel Wix-Ramos
- Clinical Neurophysiology Department, La Princesa University Hospital, Madrid, ESP
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