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Kaminski HJ, Sikorski P, Coronel SI, Kusner LL. Myasthenia gravis: the future is here. J Clin Invest 2024; 134:e179742. [PMID: 39105625 DOI: 10.1172/jci179742] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/07/2024] Open
Abstract
Myasthenia gravis (MG) stands as a prototypical antibody-mediated autoimmune disease: it is dependent on T cells and characterized by the presence of autoantibodies targeting proteins located on the postsynaptic surface of skeletal muscle, known as the neuromuscular junction. Patients with MG exhibit a spectrum of weakness, ranging from limited ocular muscle involvement to life-threatening respiratory failure. Recent decades have witnessed substantial progress in understanding the underlying pathophysiology, leading to the delineation of distinct subcategories within MG, including MG linked to AChR or MuSK antibodies as well as age-based distinction, thymoma-associated, and immune checkpoint inhibitor-induced MG. This heightened understanding has paved the way for the development of more precise and targeted therapeutic interventions. Notably, the FDA has recently approved therapeutic inhibitors of complement and the IgG receptor FcRn, a testament to our improved comprehension of autoantibody effector mechanisms in MG. In this Review, we delve into the various subgroups of MG, stratified by age, autoantibody type, and histology of the thymus with neoplasms. Furthermore, we explore both current and potential emerging therapeutic strategies, shedding light on the evolving landscape of MG treatment.
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Affiliation(s)
| | | | | | - Linda L Kusner
- Department of Pharmacology and Physiology, George Washington University, Washington, DC, USA
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Chuquisana O, Stascheit F, Keller CW, Pučić-Baković M, Patenaude AM, Lauc G, Tzartos S, Wiendl H, Willcox N, Meisel A, Lünemann JD. Functional Signature of LRP4 Antibodies in Myasthenia Gravis. NEUROLOGY(R) NEUROIMMUNOLOGY & NEUROINFLAMMATION 2024; 11:e200220. [PMID: 38507656 PMCID: PMC10959168 DOI: 10.1212/nxi.0000000000200220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/22/2023] [Accepted: 01/26/2024] [Indexed: 03/22/2024]
Abstract
BACKGROUND AND OBJECTIVES Antibodies (Abs) specific for the low-density lipoprotein receptor-related protein 4 (LRP4) occur in up to 5% of patients with myasthenia gravis (MG). The objective of this study was to profile LRP4-Ab effector actions. METHODS We evaluated the efficacy of LRP4-specific compared with AChR-specific IgG to induce Ab-dependent cellular phagocytosis (ADCP), Ab-dependent cellular cytotoxicity (ADCC), and Ab-dependent complement deposition (ADCD). Functional features were additionally assessed in an independent AChR-Ab+ MG cohort. Levels of circulating activated complement proteins and frequency of Fc glycovariants were quantified and compared with demographically matched 19 healthy controls. RESULTS Effector actions that required binding of Fc domains to cellular FcRs such as ADCC and ADCP were detectable for both LRP4-specific and AChR-specific Abs. In contrast to AChR-Abs, LRP4-binding Abs showed poor efficacy in inducing complement deposition. Levels of circulating activated complement proteins were not substantially increased in LRP4-Ab-positive MG. Frequency of IgG glycovariants carrying 2 sialic acid residues, indicative for anti-inflammatory IgG activity, was decreased in patients with LRP4-Ab-positive MG. DISCUSSION LRP4-Abs are more effective in inducing cellular FcR-mediated effector mechanisms than Ab-dependent complement activation. Their functional signature is different from AChR-specific Abs.
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Affiliation(s)
- Omar Chuquisana
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Frauke Stascheit
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Christian W Keller
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Maja Pučić-Baković
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Anne-Marie Patenaude
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Gordan Lauc
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Socrates Tzartos
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Heinz Wiendl
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Nick Willcox
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Andreas Meisel
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
| | - Jan D Lünemann
- From the Department of Neurology with Institute of Translational Neurology (O.C., C.W.K., H.W., J.D.L.), University Hospital Münster; Department of Neurology with Experimental Neurology (F.S., A.M.); Neuroscience Clinical Research Center (F.S., A.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Genos Glycoscience Research Laboratory (M.P.-B., A.-M.P., G.L.), Zagreb; Faculty of Pharmacy and Biochemistry (G.L.), University of Zagreb, Croatia; Tzartos NeuroDiagnostics (S.T.); Department of Neurobiology (S.T.), Hellenic Pasteur Institute, Athens, Greece; Nuffield Department of Clinical Neurosciences (N.W.), Weatherall Institute of Molecular Medicine, University of Oxford, United Kingdom; and Center for Stroke Research Berlin (A.G.M.), Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany
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Mihalache OA, Vilciu C, Petrescu DM, Petrescu C, Manea MC, Ciobanu AM, Ciobanu CA, Popa-Velea O, Riga S. Depression: A Contributing Factor to the Clinical Course in Myasthenia Gravis Patients. MEDICINA (KAUNAS, LITHUANIA) 2023; 60:56. [PMID: 38256317 PMCID: PMC10819146 DOI: 10.3390/medicina60010056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Revised: 12/22/2023] [Accepted: 12/26/2023] [Indexed: 01/24/2024]
Abstract
Background and Objectives: The association between myasthenia gravis (MG) and depression is intricate and characterized by bidirectional causality. In this regard, MG can be a contributing factor to depression and, conversely, depression may worsen the symptoms of MG. This study aimed to identify any differences in the progression of the disease among patients with MG who were also diagnosed with depression as compared to those without depression. Our hypothesis focused on the theory that patients with more severe MG symptoms may have a higher likelihood of suffering depression at the same time. Materials and Methods: One hundred twenty-two male and female patients (N = 122) aged over 18 with a confirmed diagnosis of autoimmune MG who were admitted to the Neurology II department of Myasthenia Gravis, Clinical Institute Fundeni in Bucharest between January 2019 and December 2020, were included in the study. Patients were assessed at baseline and after six months. The psychiatric assessment of the patients included the Hamilton Depression Rating Scale-17 items (HAM-D), and neurological status was determined with two outcome measures: Quantitative Myasthenia Gravis (QMG) and Myasthenia Gravis Activities of Daily Life (MG-ADL). The patients were divided into two distinct groups as follows: group MG w/dep, which comprised 49 MG patients diagnosed with depressive disorder who were also currently receiving antidepressant medication, and group MG w/o dep, which consisted of 73 patients who did not have depression. Results: In our study, 40.16% of the myasthenia gravis (MG) patients exhibited a comorbid diagnosis of depression. Among the MG patients receiving antidepressant treatment, baseline assessments revealed a mean MG-ADL score of 7.73 (SD = 5.05), an average QMG score of 18.40 (SD = 8.61), and a mean Ham-D score of 21.53 (SD = 7.49). After a six-month period, a statistically significant decrease was observed in the MG-ADL (2.92, SD = 1.82), QMG (7.15, SD = 4.46), and Ham-D scores (11.16, SD = 7.49) (p < 0.0001). These results suggest a significant correlation between MG severity and elevated HAM-D depression scores. Regarding the MG treatment in the group with depression, at baseline, the mean dose of oral corticosteroids was 45.10 mg (SD = 16.60). Regarding the treatment with pyridostigmine, patients with depression and undergoing antidepressant treatment remained with an increased need for pyridostigmine, 144.49 mg (SD = 51.84), compared to those in the group without depression, 107.67 mg (SD = 55.64, p < 0.001). Conclusions: Our investigation confirms that the occurrence of depressive symptoms is significantly widespread among individuals diagnosed with MG. Disease severity, along with younger age and higher doses of cortisone, is a significant factor associated with depression in patients with MG. Substantial reductions in MG-ADL and QMG scores were observed within each group after six months, highlighting the effectiveness of MG management. The findings suggest that addressing depressive symptoms in MG patients, in addition to standard MG management, can lead to improved clinical outcomes.
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Affiliation(s)
- Oana Antonia Mihalache
- Department of Doctoral Studies, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania;
- Department of Neurology, “Fundeni” Clinical Institute, 022328 Bucharest, Romania;
| | - Crisanda Vilciu
- Department of Neurology, “Fundeni” Clinical Institute, 022328 Bucharest, Romania;
- Department of Neurology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania;
| | - Diana-Mihaela Petrescu
- Department of Neurology, “Carol Davila” University of Medicine and Pharmacy, 020021 Bucharest, Romania;
| | - Cristian Petrescu
- Department of Psychiatry, “Prof. Dr. Alexandru Obregia” Clinical Hospital of Psychiatry, 041914 Bucharest, Romania; (C.P.); (M.C.M.)
- Neuroscience Department, Discipline of Psychiatry, Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania
| | - Mihnea Costin Manea
- Department of Psychiatry, “Prof. Dr. Alexandru Obregia” Clinical Hospital of Psychiatry, 041914 Bucharest, Romania; (C.P.); (M.C.M.)
- Neuroscience Department, Discipline of Psychiatry, Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania
| | - Adela Magdalena Ciobanu
- Department of Psychiatry, “Prof. Dr. Alexandru Obregia” Clinical Hospital of Psychiatry, 041914 Bucharest, Romania; (C.P.); (M.C.M.)
- Neuroscience Department, Discipline of Psychiatry, Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 020021 Bucharest, Romania
| | | | - Ovidiu Popa-Velea
- Department of Medical Psychology, Faculty of Medicine, University of Medicine and Pharmacy “Carol Davila”, 050474 Bucharest, Romania;
| | - Sorin Riga
- Department of Stress Research and Prophylaxis, “Prof. Dr. Alexandru Obregia” Clinical Hospital of Psychiatry, 041914 Bucharest, Romania;
- Romanian Academy of Medical Sciences, 927180 Bucharest, Romania
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Hayashi M. Pathophysiology of Childhood-Onset Myasthenia: Abnormalities of Neuromuscular Junction and Autoimmunity and Its Background. PATHOPHYSIOLOGY 2023; 30:599-617. [PMID: 38133144 PMCID: PMC10747330 DOI: 10.3390/pathophysiology30040043] [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: 10/28/2023] [Revised: 11/28/2023] [Accepted: 11/29/2023] [Indexed: 12/23/2023] Open
Abstract
The pathophysiology of myasthenia gravis (MG) has been largely elucidated over the past half century, and treatment methods have advanced. However, the number of cases of childhood-onset MG is smaller than that of adult MG, and the treatment of childhood-onset MG has continued to be based on research in the adult field. Research on pathophysiology and treatment methods that account for the unique growth and development of children is now desired. According to an epidemiological survey conducted by the Ministry of Health, Labour and Welfare of Japan, the number of patients with MG by age of onset in Japan is high in early childhood. In recent years, MG has been reported from many countries around the world, but the pattern of the number of patients by age of onset differs between East Asia and Western Europe, confirming that the Japanese pattern is common in East Asia. Furthermore, there are racial differences in autoimmune MG and congenital myasthenic syndromes according to immunogenetic background, and their pathophysiology and relationships are gradually becoming clear. In addition, treatment options are also recognized in different regions of the world. In this review article, I will present recent findings focusing on the differences in pathophysiology.
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Affiliation(s)
- Masatoshi Hayashi
- Department of Pediatrics, Uwajima City Hospital, Uwajima 798-8510, Japan
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Li X, Sun B, Li J, Ye W, Li M, Guan F, Wu S, Luo X, Feng J, Jia J, Liu X, Li T, Liu L. SEPSIS LEADS TO IMPAIRED MITOCHONDRIAL CALCIUM UPTAKE AND SKELETAL MUSCLE WEAKNESS BY REDUCING THE MICU1:MCU PROTEIN RATIO. Shock 2023; 60:698-706. [PMID: 37695737 PMCID: PMC10662578 DOI: 10.1097/shk.0000000000002221] [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: 05/02/2023] [Revised: 05/23/2023] [Accepted: 08/29/2023] [Indexed: 09/13/2023]
Abstract
ABSTRACT Purpose: Intensive care unit-acquired weakness (ICUAW) is a severe neuromuscular complication that frequently occurs in patients with sepsis. The precise molecular pathophysiology of mitochondrial calcium uptake 1 (MICU1) and mitochondrial calcium uniporter (MCU) in ICUAW has not been fully elucidated. Here, we speculate that ICUAW is associated with MICU1:MCU protein ratio-mediated mitochondrial calcium ([Ca 2+ ] m ) uptake dysfunction. Methods: Cecal ligation and perforation (CLP) was performed on C57BL/6J mice to induce sepsis. Sham-operated animals were used as controls. Lipopolysaccharide (LPS) (5 μg/mL) was used to induce inflammation in differentiated C2C12 myoblasts. Compound muscle action potential (CMAP) was detected using a biological signal acquisition system. Grip strength was measured using a grip-strength meter. Skeletal muscle inflammatory factors were detected using ELISA kits. The cross-sectional area (CSA) of the tibialis anterior (TA) muscle was detected by hematoxylin and eosin staining. Cytosolic calcium ([Ca 2+ ] c ) levels were measured using Fluo-4 AM. Adeno-associated virus (AAV) was injected into TA muscles for 4 weeks to overexpress MICU1 prophylactically. A lentivirus was used to infect C2C12 cells to increase MICU1 expression prophylactically. Findings: The results suggest that sepsis induces [Ca 2+ ] m uptake disorder by reducing the MICU1:MCU protein ratio, resulting in skeletal muscle weakness and muscle fiber atrophy. However, MICU1 prophylactic overexpression reversed these effects by increasing the MICU1:MCU protein ratio. Conclusions: ICUAW is associated with impaired [Ca 2+ ] m uptake caused by a decreased MICU1:MCU protein ratio. MICU1 overexpression improves sepsis-induced skeletal muscle weakness and atrophy by ameliorating the [Ca 2+ ] m uptake disorder.
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Affiliation(s)
- Xuexin Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Bowen Sun
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jie Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Wanlin Ye
- Laboratory of Mitochondria and Metabolism, West China Hospital of Sichuan University, Chengdu, China
| | - Mingjuan Li
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Fasheng Guan
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Songlin Wu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Xuerong Luo
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jianguo Feng
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Jing Jia
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Xueru Liu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
| | - Tao Li
- Laboratory of Mitochondria and Metabolism, West China Hospital of Sichuan University, Chengdu, China
| | - Li Liu
- Department of Anesthesiology, The Affiliated Hospital of Southwest Medical University, Luzhou, Sichuan Province, China
- Anesthesiology and Critical Care Medicine Key Laboratory of Luzhou, Southwest Medical University, Luzhou, Sichuan Province, China
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Almodovar JL, Mehrabyan A. Disease-Based Prognostication: Myasthenia Gravis. Semin Neurol 2023; 43:799-806. [PMID: 37751854 DOI: 10.1055/s-0043-1775791] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/28/2023]
Abstract
Myasthenia gravis (MG) is an acquired autoimmune neuromuscular junction transmission disorder that clinically presents as fluctuating or persistent weakness in various skeletal muscle groups. Neuroprognostication in MG begins with some basic observations on the natural history of the disease and known treatment outcomes. Our objective is to provide a framework that can assist a clinician who encounters the MG patient for the first time and attempts to prognosticate probable outcomes in individual patients. In this review article, we explore clinical type, age of onset, antibody status, severity of disease, thymus pathology, autoimmune, and other comorbidities as prognostic factors in MG.
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Affiliation(s)
- Jorge L Almodovar
- Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
| | - Anahit Mehrabyan
- Department of Neurology, University of North Carolina School of Medicine, Chapel Hill, North Carolina
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Lv R, Duan L, Gao J, Si J, Feng C, Hu J, Zheng X. Bioinformatics-based analysis of the roles of basement membrane-related gene AGRN in systemic lupus erythematosus and pan-cancer development. Front Immunol 2023; 14:1231611. [PMID: 37841281 PMCID: PMC10570813 DOI: 10.3389/fimmu.2023.1231611] [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: 05/30/2023] [Accepted: 09/07/2023] [Indexed: 10/17/2023] Open
Abstract
Introduction Systemic lupus erythematosus (SLE) is an autoimmune disease involving many systems and organs, and individuals with SLE exhibit unique cancer risk characteristics. The significance of the basement membrane (BM) in the occurrence and progression of human autoimmune diseases and tumors has been established through research. However, the roles of BM-related genes and their protein expression mechanisms in the pathogenesis of SLE and pan-cancer development has not been elucidated. Methods In this study, we applied bioinformatics methods to perform differential expression analysis of BM-related genes in datasets from SLE patients. We utilized LASSO logistic regression, SVM-RFE, and RandomForest to screen for feature genes and construct a diagnosis model for SLE. In order to attain a comprehensive comprehension of the biological functionalities of the feature genes, we conducted GSEA analysis, ROC analysis, and computed levels of immune cell infiltration. Finally, we sourced pan-cancer expression profiles from the TCGA and GTEx databases and performed pan-cancer analysis. Results We screened six feature genes (AGRN, PHF13, SPOCK2, TGFBI, COL4A3, and COLQ) to construct an SLE diagnostic model. Immune infiltration analysis showed a significant correlation between AGRN and immune cell functions such as parainflammation and type I IFN response. After further gene expression validation, we finally selected AGRN for pan-cancer analysis. The results showed that AGRN's expression level varied according to distinct tumor types and was closely correlated with some tumor patients' prognosis, immune cell infiltration, and other indicators. Discussion In conclusion, BM-related genes play a pivotal role in the pathogenesis of SLE, and AGRN shows immense promise as a target in SLE and the progression of multiple tumors.
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Affiliation(s)
- Rundong Lv
- Department of Clinical Pharmacy, Zibo Central Hospital, Zibo, Shandong, China
| | - Lei Duan
- Department of Clinical Pharmacy, Zibo Central Hospital, Zibo, Shandong, China
| | - Jie Gao
- Department of Clinical Pharmacy, Zibo Central Hospital, Zibo, Shandong, China
| | - Jigang Si
- Department of Clinical Pharmacy, Zibo Central Hospital, Zibo, Shandong, China
| | - Chen Feng
- Department of Pharmacy, Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China
| | - Jun Hu
- Department of Children’s Health, Zibo Central Hospital, Zibo, Shandong, China
| | - Xiulan Zheng
- School of Pharmacy, Faculty of Medicine, Macau University of Science and Technology, Macao, Macao SAR, China
- Department of Rheumatology and Immunology, The Affiliated Drum Tower Hospital of Nanjing University Medical School, Nanjing, Jiangsu, China
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8
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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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9
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Behbehani R. Ocular Myasthenia Gravis: A Current Overview. Eye Brain 2023; 15:1-13. [PMID: 36778719 PMCID: PMC9911903 DOI: 10.2147/eb.s389629] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2022] [Accepted: 01/24/2023] [Indexed: 02/05/2023] Open
Abstract
Ocular myasthenia gravis (OMG) is a neuromuscular disease characterized by autoantibody production against post-synaptic proteins in the neuromuscular junction. The pathophysiological auto-immune mechanisms of myasthenia are diverse, and this is governed primarily by the type of autoantibody production. The diagnosis of OMG relies mainly on clinical assessment, the use of serological antibody assays for acetylcholine receptors (AchR), muscle-specific tyrosine kinase (MusK), and low-density lipoprotein 4 (LPR4). Other autoantibodies against post-synaptic proteins, such as cortactin and agrin, have been detected; however, their diagnostic value and pathogenic effect are not yet clearly defined. Clinical tests such as the ice test and electrophysiologic tests, particularly single-fiber electromyography, have a valuable role in diagnosis. The treatment of OMG is primarily through cholinesterase inhibitors (pyridostigmine), and steroids are frequently required in cases of ophthalmoplegia. Other immunosuppressive therapies include antimetabolites (azathioprine, mycophenolate mofetil, methotrexate) and biological agents such as B-cell depleting agents (Rituximab) and complement inhibitors (eculizumab). Evidence is scarce on the effect of immunosuppressive therapy on altering the natural course of OMG. Clinicians must be vigilant of a myasthenic syndrome in patients using immune-check inhibitors. Reliable and consistent biomarkers are required to assess disease severity and response to therapy to optimize the management of OMG. The purpose of this review is to summarize the current trends and the latest developments in diagnosing and treating OMG.
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Affiliation(s)
- Raed Behbehani
- Neuroophthalmology Unit, Ibn Sina Hospital, Kuwait City, Kuwait,Correspondence: Raed Behbehani, Ibn Sina Hospital, P.O Box 1180, Tel +965 2224 2999, Fax +965 2249 2406, Email
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10
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Younger DS. Critical illness-associated weakness and related motor disorders. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:707-777. [PMID: 37562893 DOI: 10.1016/b978-0-323-98818-6.00031-5] [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: 08/12/2023]
Abstract
Weakness of limb and respiratory muscles that occurs in the course of critical illness has become an increasingly common and serious complication of adult and pediatric intensive care unit patients and a cause of prolonged ventilatory support, morbidity, and prolonged hospitalization. Two motor disorders that occur singly or together, namely critical illness polyneuropathy and critical illness myopathy, cause weakness of limb and of breathing muscles, making it difficult to be weaned from ventilatory support, commencing rehabilitation, and extending the length of stay in the intensive care unit, with higher rates of morbidity and mortality. Recovery can take weeks or months and in severe cases, and may be incomplete or absent. Recent findings suggest an improved prognosis of critical illness myopathy compared to polyneuropathy. Prevention and treatment are therefore very important. Its management requires an integrated team approach commencing with neurologic consultation, creatine kinase (CK) measurement, detailed electrodiagnostic, respiratory and neuroimaging studies, and potentially muscle biopsy to elucidate the etiopathogenesis of the weakness in the peripheral and/or central nervous system, for which there may be a variety of causes. These tenets of care are being applied to new cases and survivors of the coronavirus-2 disease pandemic of 2019. This chapter provides an update to the understanding and approach to critical illness motor disorders.
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Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
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11
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Younger DS. On the path to evidence-based therapy in neuromuscular disorders. HANDBOOK OF CLINICAL NEUROLOGY 2023; 195:315-358. [PMID: 37562877 DOI: 10.1016/b978-0-323-98818-6.00007-8] [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: 08/12/2023]
Abstract
Neuromuscular disorders encompass a diverse group of acquired and genetic diseases characterized by loss of motor functionality. Although cure is the goal, many therapeutic strategies have been envisioned and are being studied in randomized clinical trials and entered clinical practice. As in all scientific endeavors, the successful clinical translation depends on the quality and translatability of preclinical findings and on the predictive value and feasibility of the clinical models. This chapter focuses on five exemplary diseases: childhood spinal muscular atrophy (SMA), Charcot-Marie-Tooth (CMT) disorders, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), acquired autoimmune myasthenia gravis (MG), and Duchenne muscular dystrophy (DMD), to illustrate the progress made on the path to evidenced-based therapy.
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Affiliation(s)
- David S Younger
- Department of Clinical Medicine and Neuroscience, CUNY School of Medicine, New York, NY, United States; Department of Medicine, Section of Internal Medicine and Neurology, White Plains Hospital, White Plains, NY, United States.
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12
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Fichtner ML, Hoehn KB, Ford EE, Mane-Damas M, Oh S, Waters P, Payne AS, Smith ML, Watson CT, Losen M, Martinez-Martinez P, Nowak RJ, Kleinstein SH, O'Connor KC. Reemergence of pathogenic, autoantibody-producing B cell clones in myasthenia gravis following B cell depletion therapy. Acta Neuropathol Commun 2022; 10:154. [PMID: 36307868 PMCID: PMC9617453 DOI: 10.1186/s40478-022-01454-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 11/12/2022] Open
Abstract
Myasthenia gravis (MG) is an autoantibody-mediated autoimmune disorder of the neuromuscular junction. A small subset of patients (<10%) with MG, have autoantibodies targeting muscle-specific tyrosine kinase (MuSK). MuSK MG patients respond well to CD20-mediated B cell depletion therapy (BCDT); most achieve complete stable remission. However, relapse often occurs. To further understand the immunomechanisms underlying relapse, we studied autoantibody-producing B cells over the course of BCDT. We developed a fluorescently labeled antigen to enrich for MuSK-specific B cells, which was validated with a novel Nalm6 cell line engineered to express a human MuSK-specific B cell receptor. B cells (≅ 2.6 million) from 12 different samples collected from nine MuSK MG patients were screened for MuSK specificity. We successfully isolated two MuSK-specific IgG4 subclass-expressing plasmablasts from two of these patients, who were experiencing a relapse after a BCDT-induced remission. Human recombinant MuSK mAbs were then generated to validate binding specificity and characterize their molecular properties. Both mAbs were strong MuSK binders, they recognized the Ig1-like domain of MuSK, and showed pathogenic capacity when tested in an acetylcholine receptor (AChR) clustering assay. The presence of persistent clonal relatives of these MuSK-specific B cell clones was investigated through B cell receptor repertoire tracing of 63,977 unique clones derived from longitudinal samples collected from these two patients. Clonal variants were detected at multiple timepoints spanning more than five years and reemerged after BCDT-mediated remission, predating disease relapse by several months. These findings demonstrate that a reservoir of rare pathogenic MuSK autoantibody-expressing B cell clones survive BCDT and reemerge into circulation prior to manifestation of clinical relapse. Overall, this study provides both a mechanistic understanding of MuSK MG relapse and a valuable candidate biomarker for relapse prediction.
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Affiliation(s)
- Miriam L Fichtner
- Department of Neurology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA
- Department of Immunobiology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA
| | - Kenneth B Hoehn
- Department of Pathology, Yale School of Medicine, New Haven, CT, USA
| | - Easton E Ford
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, USA
| | - Marina Mane-Damas
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Sangwook Oh
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Patrick Waters
- Oxford Autoimmune Neurology Group, Nuffield Department of Clinical Neurosciences, University of Oxford, Oxford, UK
| | - Aimee S Payne
- Department of Dermatology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Melissa L Smith
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, USA
| | - Corey T Watson
- Department of Microbiology and Immunology, University of Louisville School of Medicine, Louisville, KY, USA
- Department of Biochemistry and Molecular Genetics, University of Louisville School of Medicine, Louisville, KY, USA
| | - Mario Losen
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Pilar Martinez-Martinez
- Department of Psychiatry and Neuropsychology, School for Mental Health and Neuroscience, Maastricht University, Maastricht, The Netherlands
| | - Richard J Nowak
- Department of Neurology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA
| | - Steven H Kleinstein
- Department of Immunobiology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA
- Department of Pathology, Yale School of Medicine, New Haven, CT, USA
- Program in Computational Biology & Bioinformatics, Yale University, New Haven, CT, USA
| | - Kevin C O'Connor
- Department of Neurology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA.
- Department of Immunobiology, Yale University School of Medicine, 300 George Street - Room 353J, New Haven, CT, 06511, USA.
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13
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Abstract
PURPOSE OF REVIEW This review summarizes recent insights into the immunopathogenesis of autoimmune myasthenia gravis (MG). Mechanistic understanding is presented according to MG disease subtypes and by leveraging the knowledge gained through the use of immunomodulating biological therapeutics. RECENT FINDINGS The past two years of research on MG have led to a more accurate definition of the mechanisms through which muscle-specific tyrosine kinase (MuSK) autoantibodies induce pathology. Novel insights have also emerged from the collection of stronger evidence on the pathogenic capacity of low-density lipoprotein receptor-related protein 4 autoantibodies. Clinical observations have revealed a new MG phenotype triggered by cancer immunotherapy, but the underlying immunobiology remains undetermined. From a therapeutic perspective, MG patients can now benefit from a wider spectrum of treatment options. Such therapies have uncovered profound differences in clinical responses between and within the acetylcholine receptor and MuSK MG subtypes. Diverse mechanisms of immunopathology between the two subtypes, as well as qualitative nuances in the autoantibody repertoire of each patient, likely underpin the variability in therapeutic outcomes. Although predictive biomarkers of clinical response are lacking, these observations have ignited the development of assays that might assist clinicians in the choice of specific therapeutic strategies. SUMMARY Recent advances in the understanding of autoantibody functionalities are bringing neuroimmunologists closer to a more detailed appreciation of the mechanisms that govern MG pathology. Future investigations on the immunological heterogeneity among MG patients will be key to developing effective, individually tailored therapies.
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Affiliation(s)
- Gianvito Masi
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511 USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06511 USA
| | - Kevin C. O’Connor
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511 USA
- Department of Immunobiology, Yale School of Medicine, New Haven, CT 06511 USA
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Racke MK, Batish SD, Lisak RP, Barohn RJ. LRP4 antibody testing in myasthenia gravis. J Neuroimmunol 2022; 371:577949. [PMID: 35973344 DOI: 10.1016/j.jneuroim.2022.577949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2022] [Accepted: 08/08/2022] [Indexed: 10/15/2022]
Affiliation(s)
- Michael K Racke
- Quest Diagnostics, 500 Plaza Drive, Secaucus, NJ 07094, USA.
| | | | - Robert P Lisak
- Department of Neurology, Wayne State University and Detroit Medical Center, Detroit, MI, USA
| | - Richard J Barohn
- Department of Neurology, School of Medicine, University of Missouri, Columbia, MO, USA
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15
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Novel treatment strategies for acetylcholine receptor antibody-positive myasthenia gravis and related disorders. Autoimmun Rev 2022; 21:103104. [PMID: 35452851 DOI: 10.1016/j.autrev.2022.103104] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 04/18/2022] [Indexed: 11/21/2022]
Abstract
The presence of autoantibodies directed against the muscle nicotinic acetylcholine receptor (AChR) is the most common cause of myasthenia gravis (MG). These antibodies damage the postsynaptic membrane of the neuromuscular junction and cause muscle weakness by depleting AChRs and thus impairing synaptic transmission. As one of the best-characterized antibody-mediated autoimmune diseases, AChR-MG has often served as a reference model for other autoimmune disorders. Classical pharmacological treatments, including broad-spectrum immunosuppressive drugs, are effective in many patients. However, complete remission cannot be achieved in all patients, and 10% of patients do not respond to currently used therapies. This may be attributed to production of autoantibodies by long-lived plasma cells which are resistant to conventional immunosuppressive drugs. Hence, novel therapies specifically targeting plasma cells might be a suitable therapeutic approach for selected patients. Additionally, in order to reduce side effects of broad-spectrum immunosuppression, targeted immunotherapies and symptomatic treatments will be required. This review presents established therapies as well as novel therapeutic approaches for MG and related conditions, with a focus on AChR-MG.
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RNF185 antisense RNA 1 (RNF185-AS1) promotes proliferation, migration, and invasion in papillary thyroid carcinoma. Anticancer Drugs 2022; 33:595-606. [PMID: 35324519 DOI: 10.1097/cad.0000000000001295] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Long noncoding RNA (lncRNA) plays an important role in multiple cancers. So far, the exact function of lncRNAs in papillary thyroid carcinoma (PTC) is unclear. The purposes of this work were to investigate the function and underlying mechanisms of RNF185 antisense RNA 1 (RNF185-AS1) in PTC. The expression of RNF185-AS1 was analyzed by quantitative real-time PCR (qRT-PCR). Colony formation, 5-ethynyl-2'-deoxyuridine, and Cell Counting Kit-8 assays were utilized to determine cell proliferation. Cell migration and invasion were tested using wound healing and transwell assays. A mouse transplantation tumor model was used for tumor growth analyses in vivo. The regulation of RNF185-AS1 on the downstream miR-429/lipoprotein receptor-related protein (LRP4) axis was predicted and identified through bioinformatic analysis, dual-luciferase reporter assay, and RNA immunoprecipitation (RIP) assay. RNF185-AS1 was dramatically overexpressed in PTC tumors and cells. High RNF185-AS1 expression was associated with bigger tumor size, lymph node metastasis, and advanced tumor-node-metastasis stage in PTC patients. Silencing of RNF185-AS1 impeded the proliferation, migration, and invasion in vitro and constrained tumorigenesis in vivo. Mechanistically, RNF185-AS1 could act as a sponge of miR-429 to regulate the expression of LRP4. In addition, downregulation of miR-429 or upregulation of LRP4 could relieve the proliferation, migration, and invasion of IHH-4 and TPC-1 cells that inhibited by RNF185-AS1 knockdown. Downregulation of RNF185-AS1 may suppress PTC progression through functioning as a sponge of miR-429 to hinder the expression of LRP4. The RNF185-AS1/miR-429/LRP4 axis will lay the groundwork for future therapeutic strategies in PTC.
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Lisak RP. Antibodies to LRP4 and Agrin Are Pathogenic in Myasthenia Gravis: At the Junction Where It Happens. Neurology 2021; 97:463-464. [PMID: 34233934 DOI: 10.1212/wnl.0000000000012471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Robert P Lisak
- From the Wayne State University School of Medicine, Detroit, MI.
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