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Jayaraman S, Wilson A, Zheng XA, Montagne JM, Pinal-Fernandez I, Mammen AL, Lloyd TE, Larman HB. Characterizing local antibody responses in the muscle of inclusion body myositis patients. J Autoimmun 2025; 154:103437. [PMID: 40424896 DOI: 10.1016/j.jaut.2025.103437] [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: 02/12/2025] [Revised: 04/14/2025] [Accepted: 05/02/2025] [Indexed: 05/29/2025]
Abstract
OBJECTIVE Sporadic inclusion body myositis (IBM) is the most common adult idiopathic inflammatory myopathy. IBM etiology has been elusive, due to both degenerative and autoimmune disease features found on muscle biopsy, and significant disease heterogeneity. Investigating the role of antibodies in the muscle of IBM patients may improve our understanding of disease pathogenesis. METHODS We used an IBM xenograft mouse model in which muscle biopsy tissue from IBM patients (n = 98) and controls (n = 131; including 54 from other types of myopathy) were implanted into immunodeficient mice (NOD-Rag1null-IL2rγnull). We quantified the amount of human IgG, IgA, and IgM in xenografted mouse sera using MesoScale Diagnostics (MSD) assay. We detected donor-derived antibody reactivities targeting autoantigens and infectious agents using Phage ImmunoPrecipitation Sequencing (PhIP-Seq). Finally, we used FR3 AmplifiKation Sequencing (FR3AK-Seq) to sequence the antibody mRNAs from a separate cohort of 146 patient biopsies (14 IBM, 22 healthy controls, 110 other myositis subtypes). RESULTS With the MSD assay we found human IgG, IgA, and IgM in a larger percentage of IBM xenografted mice versus controls. Using PhIP-Seq, we found anti-microbial reactivities secreted from IBM muscle are prevalent amongst a healthy control population but autoantigen reactivities in IBM are more unique at the peptide and protein level. Additionally, NT5C1A (IgG/IgA and IgM) and TIF1γ (IgG/A) autoantibodies are secreted from muscle tissues of 4/18 and 10/18 IBM xenograft donors, respectively. CONCLUSION Our characterization of antibody responses within the muscle of IBM patients reveals that muscle-infiltrating B cells produce both disease-associated autoantibodies and a broad spectrum of antibodies targeting non-self antigens.
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Affiliation(s)
- Sahana Jayaraman
- Institute for Cell Engineering, Division of Immunology, Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Andrew Wilson
- Department of Neurology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Xuwen Alice Zheng
- Institute for Cell Engineering, Division of Immunology, Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Janelle M Montagne
- Department of Oncology, Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Johns Hopkins University, Baltimore, MD, USA
| | - Iago Pinal-Fernandez
- Muscle Disease Section, National Institute of Arthritis and Musculoskeletal and Skin Disease, National Institutes of Health, Bethesda, MD, USA
| | - Andrew L Mammen
- Muscle Disease Section, National Institute of Arthritis and Musculoskeletal and Skin Disease, National Institutes of Health, Bethesda, MD, USA
| | - Thomas E Lloyd
- Department of Neurology, Baylor College of Medicine, Houston, TX, USA
| | - H Benjamin Larman
- Institute for Cell Engineering, Division of Immunology, Department of Pathology, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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Gao H, Lin J, Yang M, Gui M, Ji S, Bu B, Li Y. Telitacicept add-on therapy in refractory idiopathic inflammatory myopathy: insights from a pilot study. Rheumatology (Oxford) 2025; 64:2945-2952. [PMID: 39495163 DOI: 10.1093/rheumatology/keae601] [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: 04/25/2024] [Revised: 10/01/2024] [Accepted: 10/21/2024] [Indexed: 11/05/2024] Open
Abstract
OBJECTIVES This study aimed to evaluate the therapeutic efficacy of telitacicept based on the conventional treatment in adults with idiopathic inflammatory myopathy (IIM), focusing on its impact on clinical manifestations. METHODS IIM patients who had been treated with telitacicept for at least 3 months based on the conventional treatment from January 2023 to January 2024 were included in this study. The clinical response to telitacicept was determined based on the ACR/EULAR criteria for minimal, moderate and major improvement in the Total Improvement Score. Disease activity was monitored using core set measures, while myositis damage was assessed with established assessment tools. The Manual Muscle Test for eight muscle groups (MMT-8) was used to assess the muscle performance. RESULTS A total of 11 patients administered with telitacicept (160 mg per week) were included in this study. Post-treatment assessments revealed improvements in all patients according to ACR/EULAR criteria. Notably, there was a significant reduction in the prednisone dosage from baseline to last visit [27.05 (12.47) to 12.05 (7.32) mg; P < 0.005]. An enhancement was observed in the MMT-8 score [which improved from 109.18 (14.18) to 137.64 (15.28); P < 0.005], and there was a reduction in creatine kinase level [from 2670.27 (2675.00) to 561.09 (754.09) U/l; P < 0.05]. CONCLUSION Telitacicept demonstrated effectiveness in treating refractory inflammatory myopathy, contributing to a significant reduction in steroid dosage among the patients. These findings highlight the potential of telitacicept as a valuable therapeutic option in the management of IIM.
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Affiliation(s)
- Huajie Gao
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Jing Lin
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mengge Yang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Mengcui Gui
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Suqiong Ji
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bitao Bu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Yue Li
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
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Nakazawa M, Horuluoglu B, de Vries C, Lodin K, Malmström V, Lundberg IE, Grönwall C. CD73 low B-cell phenotypes and distinct cytokine profiles in patients with active anti-Jo-1 antibody positive idiopathic inflammatory myopathies. RMD Open 2025; 11:e005401. [PMID: 40210261 PMCID: PMC11987157 DOI: 10.1136/rmdopen-2024-005401] [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: 12/26/2024] [Accepted: 03/25/2025] [Indexed: 04/12/2025] Open
Abstract
OBJECTIVES We performed multiparameter phenotyping of peripheral B cells in anti-Jo-1 antibody positive idiopathic inflammatory myopathies (IIM) to delineate disease-associated immunological profiles and the influence of B cells on disease activity. METHODS Purified B cells from peripheral blood mononuclear cells from 16 patients with anti-Jo-1 antibody positive IIM (7 with untreated active IIM, 4 with active and treated IIM and 5 with inactive IIM) were analysed by multiparameter spectral flow cytometry. Dimensionality reduction and clustering analysis were applied to pre-gated CD19+B cells. Serum levels of 21 cytokines and anti-Jo-1 IgG autoantibodies were determined. All patients with IIM in this study were positive for anti-Jo-1 antibody. RESULTS Anti-Jo-1 antibody levels correlated positively to disease activity. Flow cytometry demonstrated B-cell dysregulation with significantly lower CD73 expression on naïve, switched memory and double negative B cells in patients with active IIM. Clustering analysis further revealed expansions of CD73- IgM+naïve B cells and CD73- CD95+ switched memory B cells in active IIM. In unswitched memory B cells, CD73+CD21+ cells were decreased in active IIM. Patients with active IIM had significantly higher serum levels of B-cell activating factor, inducible protein-10, interleukin-6 and sCD40L which correlated with changes in B-cell populations. CONCLUSIONS Since CD73 has an immunoregulatory function by modulating the ATP/adenosine pathway, which is also targeted by methotrexate, the low CD73 B-cell expression in anti-Jo-1 antibody-positive IIM may lead to B-cell hyperactivation. These novel findings further highlight B cells as central in the pathogenesis of IIM and important therapeutic targets.
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Affiliation(s)
- Maho Nakazawa
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
- Japan Society for the Promotion of Science, Tokyo, Japan
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine, Tokyo, Japan
| | - Begum Horuluoglu
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Charlotte de Vries
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Karin Lodin
- Department of Gastro, Dermatology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden
| | - Vivianne Malmström
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
| | - Ingrid E Lundberg
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
- Department of Gastro, Dermatology and Rheumatology, Karolinska University Hospital, Stockholm, Sweden
| | - Caroline Grönwall
- Division of Rheumatology, Department of Medicine, Solna, Karolinska Institutet, Stockholm, Karolinska University Hospital, Center for Molecular Medicine, Stockholm, Sweden
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Manwatkar A, Naresh K, Mathew J, Nair AV, Goel R, Yadav B, Prakash JAJ, Das JK, Sivadasan A. Comparison of rituximab efficacy in treatment-naïve and refractory inflammatory myopathies: experiences from a tertiary care centre. Rheumatology (Oxford) 2025; 64:2091-2098. [PMID: 38814804 DOI: 10.1093/rheumatology/keae307] [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: 10/24/2023] [Revised: 01/26/2024] [Accepted: 03/22/2024] [Indexed: 06/01/2024] Open
Abstract
OBJECTIVES To determine whether rituximab (RTX) is effective in 'treatment-naïve' idiopathic inflammatory myopathies (IIM), and whether there could be differential treatment responses between 'treatment-naïve' and treatment 'refractory' IIM. METHODS Data were obtained from a prospectively maintained database comprising patients with IIM treated with RTX. Patient details were obtained at baseline, 3- and 6-months intervals, and at subsequent follow-up visits. Treatment response was categorized as improved, worsening or stable based on Manual Muscle Testing 8 (MMT8) scores, patient global and physician global improvement for skin and joint symptoms improvement, and spirometry at 6 months. The time to clinical improvement and remission were noted and survival analysis curves were constructed. RESULTS Sixty patients with IIM (including 18 with anti-signal recognition particle myopathy) were included, of whom 33 who received RTX were treatment naïve. The remaining 27 were started on RTX for refractory myopathy. The mean age was 39 years (s.d. 12.58) in the 'treatment-naïve' group and 43 years (s.d. 12.12) in the 'refractory' group. At 6 months of follow-up, 48/55 (87%) patients showed response, 31/31 (100%) in 'treatment-naïve' and 17/24 (70%) in 'refractory' cases, P = 0.006*. In the refractory group, seven (29%) had stable disease. The mean changes in MMT8 were significantly more in the 'treatment-naïve' group [13.41 (s.d. 7.31)] compared with 'refractory' IIM [8.33 (s.d. 7.92)] (P = 0.017*). The majority of patients were able to reduce the dose to <5 mg/day before 6 months. No major adverse events were reported over the median follow-up of 24 (interquartile range 36) months. CONCLUSIONS RTX is effective and safe across the spectrum of IIM. Early use in disease is associated with better outcomes.
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Affiliation(s)
- Abhilasha Manwatkar
- Department of Clinical Immunology and Rheumatology, Christian Medical College Vellore, Vellore, India
| | - Kancha Naresh
- Department of Neuroscience, Christian Medical College Vellore, Vellore, India
| | - John Mathew
- Department of Clinical Immunology and Rheumatology, Christian Medical College Vellore, Vellore, India
| | - Aditya V Nair
- Department of Neuroscience, Christian Medical College Vellore, Vellore, India
| | - Ruchika Goel
- Department of Clinical Immunology and Rheumatology, Christian Medical College Vellore, Vellore, India
| | - Bijesh Yadav
- Department of Biostatistics, Christian Medical College Vellore, Vellore, India
| | | | - John Kumar Das
- Department of Clinical Immunology and Rheumatology, Christian Medical College Vellore, Vellore, India
| | - Ajith Sivadasan
- Department of Neuroscience, Christian Medical College Vellore, Vellore, India
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Pan Z, Li M, Zhang P, Li T, Liu R, Liu J, Liu S, Zhang Y. Peripheral Blood Lymphocyte Subsets and Heterogeneity of B Cell Subsets in Patients of Idiopathic Inflammatory Myositis with Different Myositis-specific Autoantibodies. Inflammation 2025; 48:118-132. [PMID: 38755405 DOI: 10.1007/s10753-024-02052-z] [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: 02/06/2024] [Revised: 05/08/2024] [Accepted: 05/10/2024] [Indexed: 05/18/2024]
Abstract
Idiopathic inflammatory myopathies (IIM) are a group of myopathies that present with muscle weakness and multiple extra-muscular manifestations, in which lymphocytes play central roles in myositis pathogenesis. This study aimed to explore the clinical characteristics of lymphocyte subsets, especially B cell subsets, in patients with IIM. Our study included 176 patients with active IIM and 210 gender/age-matched healthy controls (HCs). Compared to HCs, patients have reduced counts of T cells, B cells, and natural killer cells. In addition, B cell subsets from 153 patients with IIM and 92 HCs were characterized. Patients had a lower percentage of memory B cells and translational memory B cells, while those patients were with an elevated percentage of CD19+ B cells, plasmablast and naïve B cells compared with HCs. Moreover, to further explore the heterogeneity of B cells in IIM, patients were categorized into three clusters based on clustering analysis. Cluster 1 was dominated by CD19+ B cells, Bregs and naïve B cells, cluster 3 was dominated by memory B cells and plasmablast, and cluster 2 had the highest proportion of translational memory B cells. Notably, patients in cluster 1 presented with higher CK levels, indicating muscle damage, whereas patients in cluster 3 showed a higher incidence of chest tightness. Our study indicated that lymphopenia is a common manifestation in patients with IIM. B cell subsets are abnormally expressed and showed high heterogeneity in patients with IIM. The patients with IIM were divided into three different clusters with different percentages of chest tightness and distinct CK levels.
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Affiliation(s)
- Zhou Pan
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Mengdi Li
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
- Department of Rheumatology and Clinical Immunology, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Panpan Zhang
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Tianqi Li
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Rui Liu
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jia Liu
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Shengyun Liu
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China.
| | - Yusheng Zhang
- Department of Rheumatology and Clinical Immunology, The first affiliated Hospital of Zhengzhou University, Zhengzhou, China.
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Alf V, Opmeer Y, Shelton GD, Grinwis GCM, Matiasek K, Rosati M, Mandigers PJJ. Pathologic Changes in and Immunophenotyping of Polymyositis in the Dutch Kooiker Dog. Animals (Basel) 2024; 14:2519. [PMID: 39272303 PMCID: PMC11394232 DOI: 10.3390/ani14172519] [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: 06/30/2024] [Revised: 08/26/2024] [Accepted: 08/28/2024] [Indexed: 09/15/2024] Open
Abstract
Earlier, we described a breed-specific inflammatory myopathy in Dutch Kooiker dogs (Het Nederlandse Kooikerhondje), one of the nine Dutch breeds. The disease commonly manifests itself with clinical signs of difficulty walking, muscle weakness, exercise intolerance, and/or dysphagia. In nearly all dogs' creatine kinase (CK) activity was elevated. Histopathology reveals the infiltration of inflammatory cells within the skeletal muscles. The objective of this study was to further investigate and characterize the histopathological changes in muscle tissue and immunophenotype the inflammatory infiltrates. FFPE fixed-muscle biopsies from 39 purebred Kooiker dogs were included and evaluated histopathologically according to a tailored classification scheme for skeletal muscle inflammation. As in other breed-related inflammatory myopathies, multifocal, mixed, and predominantly mononuclear cell infiltration was present, with an initial invasion of viable muscle fibres and the surrounding stroma leading to inflammation, necrosis, and tissue damage. Immunophenotyping primarily revealed lymphohistiocytic infiltrates, with CD3+ T-cells being the predominant inflammatory cell type, accompanied by CD8+ cytotoxic T-cells. The concurrent expression of MHC-II class molecules on myofibres suggests their involvement in initiating and maintaining inflammation. Additionally, CD20+ B-cells were identified, though in lower numbers compared to T-cells, and IBA-1-positive macrophages were frequently seen. These findings suggest a breed-specific subtype of polymyositis in Kooiker dogs, akin to other breeds. This study sheds light on the immune response activation, combining adaptive and innate mechanisms, contributing to our understanding of polymyositis in this breed.
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Affiliation(s)
- Vanessa Alf
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universität Munich, 80539 Munich, Germany
| | - Yvet Opmeer
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, The Netherlands
| | - G Diane Shelton
- Department of Pathology, School of Medicine, University of California, San Diego, CA 92093-0709, USA
| | - Guy C M Grinwis
- Department of Biomolecular Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CL Utrecht, The Netherlands
| | - Kaspar Matiasek
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universität Munich, 80539 Munich, Germany
| | - Marco Rosati
- Section of Clinical and Comparative Neuropathology, Centre for Clinical Veterinary Medicine, Ludwig-Maximilians-Universität Munich, 80539 Munich, Germany
| | - Paul J J Mandigers
- Expertise Centre of Genetics, Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, The Netherlands
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Ma Y, Lai J, Wan Q, Chen Z, Sun L, Zhang Q, Guan C, Li Q, Wu J. Identification of common mechanisms and biomarkers for dermatomyositis and atherosclerosis based on bioinformatics analysis. Skin Res Technol 2024; 30:e13808. [PMID: 38899746 PMCID: PMC11187814 DOI: 10.1111/srt.13808] [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: 04/13/2024] [Accepted: 05/28/2024] [Indexed: 06/21/2024]
Abstract
BACKGROUND Dermatomyositis (DM) manifests as an autoimmune and inflammatory condition, clinically characterized by subacute progressive proximal muscle weakness, rashes or both along with extramuscular manifestations. Literature indicates that DM shares common risk factors with atherosclerosis (AS), and they often co-occur, yet the etiology and pathogenesis remain to be fully elucidated. This investigation aims to utilize bioinformatics methods to clarify the crucial genes and pathways that influence the pathophysiology of both DM and AS. METHOD Microarray datasets for DM (GSE128470, GSE1551, GSE143323) and AS (GSE100927, GSE28829, GSE43292) were retrieved from the Gene Expression Omnibus (GEO) database. The weighted gene co-expression network analysis (WGCNA) was used to reveal their co-expressed modules. Differentially expression genes (DEGs) were identified using the "limma" package in R software, and the functions of common DEGs were determined by functional enrichment analysis. A protein-protein interaction (PPI) network was established using the STRING database, with central genes evaluated by the cytoHubba plugin, and validated through external datasets. Immune infiltration analysis of the hub genes was conducted using the CIBERSORT method, along with Gene Set Enrichment Analysis (GSEA). Finally, the NetworkAnalyst platform was employed to examine the transcription factors (TFs) responsible for regulating pivotal crosstalk genes. RESULTS Utilizing WGCNA analysis, a total of 271 overlapping genes were pinpointed. Subsequent DEG analysis revealed 34 genes that are commonly found in both DM and AS, including 31 upregulated genes and 3 downregulated genes. The Degree Centrality algorithm was applied separately to the WGCNA and DEG collections to select the 15 genes with the highest connectivity, and crossing the two gene sets yielded 3 hub genes (PTPRC, TYROBP, CXCR4). Validation with external datasets showed their diagnostic value for DM and AS. Analysis of immune infiltration indicates that lymphocytes and macrophages are significantly associated with the pathogenesis of DM and AS. Moreover, GSEA analysis suggested that the shared genes are enriched in various receptor interactions and multiple cytokines and receptor signaling pathways. We coupled the 3 hub genes with their respective predicted genes, identifying a potential key TF, CBFB, which interacts with all 3 hub genes. CONCLUSION This research utilized comprehensive bioinformatics techniques to explore the shared pathogenesis of DM and AS. The three key genes, including PTPRC, TYROBP, and CXCR4, are related to the pathogenesis of DM and AS. The central genes and their correlations with immune cells may serve as potential diagnostic and therapeutic targets.
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Affiliation(s)
- Yirong Ma
- Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Junyu Lai
- Department of cardiovascularAffiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Qiang Wan
- Department of cardiovascularAffiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Zhengtao Chen
- Department of cardiovascularAffiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Liqiang Sun
- Department of cardiovascularAffiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Qinhe Zhang
- Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Chengyan Guan
- Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Qiming Li
- Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
| | - Jianguang Wu
- Department of cardiovascularAffiliated Hospital of Jiangxi University of Traditional Chinese MedicineNanchangJiangxiChina
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Guglielmi V, Cheli M, Tonin P, Vattemi G. Sporadic Inclusion Body Myositis at the Crossroads between Muscle Degeneration, Inflammation, and Aging. Int J Mol Sci 2024; 25:2742. [PMID: 38473988 PMCID: PMC10932328 DOI: 10.3390/ijms25052742] [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: 12/27/2023] [Revised: 02/19/2024] [Accepted: 02/22/2024] [Indexed: 03/14/2024] Open
Abstract
Sporadic inclusion body myositis (sIBM) is the most common muscle disease of older people and is clinically characterized by slowly progressive asymmetrical muscle weakness, predominantly affecting the quadriceps, deep finger flexors, and foot extensors. At present, there are no enduring treatments for this relentless disease that eventually leads to severe disability and wheelchair dependency. Although sIBM is considered a rare muscle disorder, its prevalence is certainly higher as the disease is often undiagnosed or misdiagnosed. The histopathological phenotype of sIBM muscle biopsy includes muscle fiber degeneration and endomysial lymphocytic infiltrates that mainly consist of cytotoxic CD8+ T cells surrounding nonnecrotic muscle fibers expressing MHCI. Muscle fiber degeneration is characterized by vacuolization and the accumulation of congophilic misfolded multi-protein aggregates, mainly in their non-vacuolated cytoplasm. Many players have been identified in sIBM pathogenesis, including environmental factors, autoimmunity, abnormalities of protein transcription and processing, the accumulation of several toxic proteins, the impairment of autophagy and the ubiquitin-proteasome system, oxidative and nitrative stress, endoplasmic reticulum stress, myonuclear degeneration, and mitochondrial dysfunction. Aging has also been proposed as a contributor to the disease. However, the interplay between these processes and the primary event that leads to the coexistence of autoimmune and degenerative changes is still under debate. Here, we outline our current understanding of disease pathogenesis, focusing on degenerative mechanisms, and discuss the possible involvement of aging.
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Affiliation(s)
- Valeria Guglielmi
- Cellular and Molecular Biology of Cancer Program, NCI-Designated Cancer Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA;
- Immunity and Pathogenesis Program, Infectious and Inflammatory Disease Center, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, CA 92037, USA
| | - Marta Cheli
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (M.C.); (P.T.)
| | - Paola Tonin
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (M.C.); (P.T.)
| | - Gaetano Vattemi
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, 37134 Verona, Italy; (M.C.); (P.T.)
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Dong Y, Wang T, Wu H. Tertiary lymphoid structures in autoimmune diseases. Front Immunol 2024; 14:1322035. [PMID: 38259436 PMCID: PMC10800951 DOI: 10.3389/fimmu.2023.1322035] [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: 10/15/2023] [Accepted: 12/18/2023] [Indexed: 01/24/2024] Open
Abstract
Tertiary lymphoid structures (TLSs) are organized lymphoid-like aggregations in non-lymphoid tissues. Tissues with chronic and persistent inflammation infiltration may drive and form ectopic germinal center-like structures, which are very common in autoimmune diseases, chronic infections, and tumor microenvironments. However, the mechanisms governing the formation of TLSs are still being explored. At present, it is not clear whether the formation of TLSs is associated with local uncontrolled immune inflammatory responses. While TLSs suggest a good prognosis in tumors, the opposite is true in autoimmune diseases. This review article will discuss the current views on initiating and maintaining TLSs and the potential therapeutic target in autoimmune diseases.
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Affiliation(s)
- Yuanji Dong
- Department of Rheumatology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
| | - Ting Wang
- Department of Respiratory Disease, Thoracic Disease Center, The First Affiliated Hospital, College of Medicine, Zhejiang University, Hangzhou, Zhejiang, China
| | - Huaxiang Wu
- Department of Rheumatology, The Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, Zhejiang, China
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Carstens PO, Müllar LM, Wrede A, Zechel S, Wachowski MM, Brandis A, Krause S, Zierz S, Schmidt J. Skeletal muscle fibers produce B-cell stimulatory factors in chronic myositis. Front Immunol 2023; 14:1177721. [PMID: 37731487 PMCID: PMC10508232 DOI: 10.3389/fimmu.2023.1177721] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 06/16/2023] [Indexed: 09/22/2023] Open
Abstract
Introduction We aimed to identify B-cell-mediated immunomechanisms in inclusion body myositis (IBM) and polymyositis (PM) as part of the complex pathophysiology. Materials and methods Human primary myotube cultures were derived from orthopedic surgery. Diagnostic biopsy specimens from patients with IBM (n=9) and PM (n=9) were analyzed for markers of B cell activation (BAFF and APRIL) and for chemokines that control the recruitment of B cells (CXCL-12 and CXCL-13). Results were compared to biopsy specimens without myopathic changes (n=9) and hereditary muscular dystrophy (n=9). Results The mRNA expression of BAFF, APRIL, and CXCL-13 was significantly higher in IBM and PM compared to controls. Patients with IBM displayed the highest number of double positive muscle fibers for BAFF and CXCL-12 (48%) compared to PM (25%), muscular dystrophy (3%), and non-myopathic controls (0%). In vitro, exposure of human myotubes to pro-inflammatory cytokines led to a significant upregulation of BAFF and CXCL-12, but APRIL and CXCL-13 remained unchanged. Conclusion The results substantiate the hypothesis of an involvement of B cell-associated mechanisms in the pathophysiology of IBM and PM. Muscle fibers themselves seem to contribute to the recruitment of B cells and sustain inflammation.
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Affiliation(s)
- Per-Ole Carstens
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Luisa M. Müllar
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Arne Wrede
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
- Institute of Neuropathology, Saarland University Medical Center and Medical Faculty of Saarland University, Homburg, Germany
| | - Sabrina Zechel
- Institute of Neuropathology, University Medical Center Göttingen, Göttingen, Germany
| | - Martin M. Wachowski
- Department of Trauma Surgery, Orthopaedics and Plastic Surgery, University Medical Center Göttingen, Göttingen, Germany
| | - Almuth Brandis
- Department of Pathology, Klinikum Region Hannover, Hannover, Germany
- Institute of Pathology and Neuropathology, Medical University Hannover, Hannover, Germany
| | - Sabine Krause
- Friedrich-Baur-Institute, Department of Neurology, Ludwig-Maximilians-University of München, München, Germany
| | - Stephan Zierz
- Department of Neurology, University Hospital Halle/Saale, Halle, Germany
| | - Jens Schmidt
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
- Department of Neurology and Pain Treatment, Neuromuscular Center, Center for Translational Medicine, Immanuel Klinik Rüdersdorf, University Hospital of the Brandenburg Medical School Theodor Fontane, Rüdersdorf bei Berlin, Germany
- Faculty of Health Sciences Brandenburg, Brandenburg Medical School Theodor Fontane, Rüdersdorf bei, Berlin, Germany
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11
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Anang DC, Walter HAW, Lim J, Niewold I, van der Weele L, Aronica E, Eftimov F, Raaphorst J, van Schaik BDC, van Kampen AHC, van der Kooi AJ, de Vries N. B-cell receptor profiling before and after IVIG monotherapy in newly diagnosed idiopathic inflammatory myopathies. Rheumatology (Oxford) 2023; 62:2585-2593. [PMID: 36321862 PMCID: PMC10321087 DOI: 10.1093/rheumatology/keac602] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Accepted: 10/06/2022] [Indexed: 07/20/2023] Open
Abstract
OBJECTIVE To unravel B-cell receptor (BcR) characteristics in muscle tissues and peripheral blood and gain more insight into BcR repertoire changes in peripheral blood in idiopathic inflammatory myopathies (IIMs), and study how this correlates to the clinical response to IVIG. METHODS Nineteen treatment-naive patients with newly diagnosed IIM were prospectively treated with IVIG monotherapy. RNA-based BcR repertoire sequencing was performed in muscle biopsies collected before, and in peripheral blood (PB) collected before and nine weeks after IVIG treatment. Results were correlated to patients' clinical improvement based on the total improvement score (TIS). RESULTS Prior to IVIG treatment, BcR clones found in muscle tissue could be retrieved in peripheral blood. Nine weeks after IVIG treatment, new patient-specific dominant BcR clones appeared in peripheral blood while pre-treatment dominant BcR clones disappeared. The cumulative frequency of all dominant BcR clones before treatment was significantly higher in individuals who responded to IVIG compared with those who did not respond to IVIG, and correlated with a higher CK. During follow-up, a decrease in the cumulative frequency of all dominant clones correlated with a higher TIS. CONCLUSION In treatment-naive patients with newly diagnosed IIM, muscle tissue and peripheral blood share expanded BcR clones. In our study a higher cumulative frequency of dominant BcR clones in blood before treatment was associated with a higher CK and better treatment response, suggesting that response to IVIG may depend on the composition of the pre-treatment BcR repertoire.
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Affiliation(s)
| | | | - Johan Lim
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Ilse Niewold
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Department of Genome analysis, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - Linda van der Weele
- Department of Rheumatology and Clinical Immunology, Amsterdam Rheumatology and Immunology Center, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
- Department of Experimental Immunology, Amsterdam Infection and Immunity Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Eleonora Aronica
- Department of (Neuro)Pathology, Amsterdam Neuroscience, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Filip Eftimov
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Joost Raaphorst
- Department of Neurology, Amsterdam UMC, University of Amsterdam, Amsterdam Neuroscience, Amsterdam, The Netherlands
| | - Barbera D C van Schaik
- Bioinformatics Laboratory, Department of Epidemiology and Data science, Amsterdam Public Health Institute, Amsterdam Infection and Immunity Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Antoine H C van Kampen
- Bioinformatics Laboratory, Department of Epidemiology and Data science, Amsterdam Public Health Institute, Amsterdam Infection and Immunity Institute, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | | | - Niek de Vries
- Correspondence to: Niek de Vries, Department of Rheumatology & Clinical Immunology and Department of Experimental Immunology, Amsterdam Infection & Immunity Institute, Amsterdam UMC, University of Amsterdam, PO. Box 22600, Meibergdreef 9, 1105AZ Amsterdam, The Netherlands. E-mail:
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12
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Jiang R, Roy B, Wu Q, Mohanty S, Nowak RJ, Shaw AC, Kleinstein SH, O’Connor KC. The Plasma Cell Infiltrate Populating the Muscle Tissue of Patients with Inclusion Body Myositis Features Distinct B Cell Receptor Repertoire Properties. Immunohorizons 2023; 7:310-322. [PMID: 37171806 PMCID: PMC10579972 DOI: 10.4049/immunohorizons.2200078] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 04/25/2023] [Indexed: 05/13/2023] Open
Abstract
Inclusion body myositis (IBM) is an autoimmune and degenerative disorder of skeletal muscle. The B cell infiltrates in IBM muscle tissue are predominantly fully differentiated Ab-secreting plasma cells, with scarce naive or memory B cells. The role of this infiltrate in the disease pathology is not well understood. To better define the humoral response in IBM, we used adaptive immune receptor repertoire sequencing, of human-derived specimens, to generate large BCR repertoire libraries from IBM muscle biopsies and compared them to those generated from dermatomyositis, polymyositis, and circulating CD27+ memory B cells, derived from healthy controls and Ab-secreting cells collected following vaccination. The repertoire properties of the IBM infiltrate included the following: clones that equaled or exceeded the highly clonal vaccine-associated Ab-secreting cell repertoire in size; reduced somatic mutation selection pressure in the CDRs and framework regions; and usage of class-switched IgG and IgA isotypes, with a minor population of IgM-expressing cells. The IBM IgM-expressing population revealed unique features, including an elevated somatic mutation frequency and distinct CDR3 physicochemical properties. These findings demonstrate that some of IBM muscle BCR repertoire characteristics are distinct from dermatomyositis and polymyositis and circulating Ag-experienced subsets, suggesting that it may form through selection by disease-specific Ags.
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Affiliation(s)
- Roy Jiang
- Department of Immunobiology, Yale School of Medicine, New Haven, CT
| | - Bhaskar Roy
- Department of Neurology, Yale School of Medicine, New Haven, CT
| | - Qian Wu
- Department of Pathology, University of Connecticut School of Medicine, Farmington, CT
| | - Subhasis Mohanty
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT
| | | | - Albert C. Shaw
- Section of Infectious Diseases, Department of Internal Medicine, Yale School of Medicine, New Haven, CT
| | - Steven H. Kleinstein
- Department of Immunobiology, Yale School of Medicine, New Haven, CT
- Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT
- Department of Pathology, Yale School of Medicine, New Haven, CT
| | - Kevin C. O’Connor
- Department of Immunobiology, Yale School of Medicine, New Haven, CT
- Department of Neurology, Yale School of Medicine, New Haven, CT
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13
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Abstract
The autoimmune inflammatory myopathies constitute a heterogeneous group of acquired myopathies that have in common the presence of endomysial inflammation and moderate to severe muscle weakness. Based on currently evolved distinct clinical, histologic, immunopathologic, and autoantibody features, these disorders can be best classified as dermatomyositis, necrotizing autoimmune myositis, antisynthetase syndrome-overlap myositis, and inclusion body myositis. Although polymyositis is no longer considered a distinct subset but rather an extinct entity, it is herein described because its clinicopathologic information has provided over many years fundamental information on T-cell-mediated myocytotoxicity, especially in reference to inclusion body myositis. Each inflammatory myopathy subset has distinct immunopathogenesis, prognosis, and response to immunotherapies, necessitating the need to correctly diagnose each subtype from the outset and avoid disease mimics. The paper describes the main clinical characteristics that aid in the diagnosis of each myositis subtype, highlights the distinct features on muscle morphology and immunopathology, elaborates on the potential role of autoantibodies in pathogenesis or diagnosis , and clarifies common uncertainties in reference to putative triggering factors such as statins and viruses including the 2019-coronavirus-2 pandemic. It extensively describes the main autoimmune markers related to autoinvasive myocytotoxic T-cells, activated B-cells, complement, cytokines, and the possible role of innate immunity. The concomitant myodegenerative features seen in inclusion body myositis along with their interrelationship between inflammation and degeneration are specifically emphasized. Finally, practical guidelines on the best therapeutic approaches are summarized based on up-to-date knowledge and controlled studies, highlighting the prospects of future immunotherapies and ongoing controversies.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA, United States; Neuroimmunology Unit National and Kapodistrian University of Athens Medical School, Athens, Greece.
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14
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Skeletal muscle provides the immunological micro-milieu for specific plasma cells in anti-synthetase syndrome-associated myositis. Acta Neuropathol 2022; 144:353-372. [PMID: 35612662 PMCID: PMC9288384 DOI: 10.1007/s00401-022-02438-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Revised: 04/08/2022] [Accepted: 05/13/2022] [Indexed: 11/17/2022]
Abstract
Anti-synthetase syndrome (ASyS)-associated myositis is a major subgroup of the idiopathic inflammatory myopathies (IIM) and is characterized by disease chronicity with musculoskeletal, dermatological and pulmonary manifestations. One of eight autoantibodies against the aminoacyl-transferase RNA synthetases (ARS) is detectable in the serum of affected patients. However, disease-specific therapeutic approaches have not yet been established.To obtain a deeper understanding of the underlying pathogenesis and to identify putative therapeutic targets, we comparatively investigated the most common forms of ASyS associated with anti-PL-7, anti-PL-12 and anti-Jo-1. Our cohort consisted of 80 ASyS patients as well as healthy controls (n = 40), diseased controls (n = 40) and non-diseased controls (n = 20). We detected a reduced extent of necrosis and regeneration in muscle biopsies from PL-12+ patients compared to Jo-1+ patients, while PL-7+ patients had higher capillary dropout in biopsies of skeletal muscle. Aside from these subtle alterations, no significant differences between ASyS subgroups were observed. Interestingly, a tissue-specific subpopulation of CD138+ plasma cells and CXCL12+/CXCL13+CD20+ B cells common to ASyS myositis were identified. These cells were localized in the endomysium associated with alkaline phosphatase+ activated mesenchymal fibroblasts and CD68+MHC-II+CD169+ macrophages. An MHC-I+ and MHC-II+ MxA negative type II interferon-driven milieu of myofiber activation, topographically restricted to the perifascicular area and the adjacent perimysium, as well as perimysial clusters of T follicular helper cells defined an extra-medullary immunological niche for plasma cells and activated B cells. Consistent with this, proteomic analyses of muscle tissues from ASyS patients demonstrated alterations in antigen processing and presentation. In-depth immunological analyses of peripheral blood supported a B-cell/plasma-cell-driven pathology with a shift towards immature B cells, an increase of B-cell-related cytokines and chemokines, and activation of the complement system. We hypothesize that a B-cell-driven pathology with the presence and persistence of a specific subtype of plasma cells in the skeletal muscle is crucially involved in the self-perpetuating chronicity of ASyS myositis. This work provides the conceptual framework for the application of plasma-cell-targeting therapies in ASyS myositis.
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15
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McLeish E, Slater N, Sooda A, Wilson A, Coudert JD, Lloyd TE, Needham M. Inclusion body myositis: The interplay between ageing, muscle degeneration and autoimmunity. Best Pract Res Clin Rheumatol 2022; 36:101761. [PMID: 35760741 DOI: 10.1016/j.berh.2022.101761] [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] [Indexed: 11/19/2022]
Abstract
Inclusion body myositis (IBM) is a slowly progressive muscle disease affecting ageing individuals. IBM presents with a distinctive pattern of weakness involving the quadriceps and finger flexor muscles, although other muscles including pharyngeal muscles become affected over time. Pathological hallmarks of IBM include autoimmune features, including endomysial infiltration by highly differentiated T cells, as well as degenerative features marked by intramyofibre protein aggregates organised into inclusion bodies. Despite some progress in understanding the cellular pathways involved in IBM, it remains untreatable, and the progression of the disease leads to progressive weakness, disability, wheelchair dependency and loss of independence. Therefore, there is an urgent need to improve our understanding of the underlying mechanisms and pathways involved in this disease to identify new treatment targets. Here, we discuss the current understanding of aetiopathogenesis, the interrelationship between autoimmunity and degeneration, and how ageing is a major influencer of both these features.
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Affiliation(s)
- E McLeish
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia.
| | - N Slater
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
| | - A Sooda
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia
| | - A Wilson
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - J D Coudert
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia; Perron Institute for Neurological and Translational Science, Perth, WA, Australia; School of Medicine, University of Notre Dame, Fremantle, WA, Australia
| | - T E Lloyd
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
| | - M Needham
- Centre for Molecular Medicine and Innovative Therapeutics, Murdoch University, Perth, WA, Australia; Perron Institute for Neurological and Translational Science, Perth, WA, Australia; School of Medicine, University of Notre Dame, Fremantle, WA, Australia; Fiona Stanley Hospital, Department of Neurology, Perth, WA, Australia
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16
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Tsamis KI, Boutsoras C, Kaltsonoudis E, Pelechas E, Nikas IP, Simos YV, Voulgari PV, Sarmas I. Clinical features and diagnostic tools in idiopathic inflammatory myopathies. Crit Rev Clin Lab Sci 2021; 59:219-240. [PMID: 34767470 DOI: 10.1080/10408363.2021.2000584] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Idiopathic inflammatory myopathies (IIMs) are rare autoimmune disorders affecting primarily muscles, but other organs can be involved. This review describes the clinical features, diagnosis and treatment for IIMs, namely polymyositis (PM), dermatomyositis (DM), sporadic inclusion body myositis (sIBM), immune-mediated necrotizing myopathy (IMNM), and myositis associated with antisynthetase syndrome (ASS). The diagnostic approach has been updated recently based on the discovery of circulating autoantibodies, which has enhanced the management of patients. Currently, validated classification criteria for IIMs allow clinical studies with well-defined sets of patients but diagnostic criteria to guide the care of individual patients in routine clinical practice are still missing. This review analyzes the clinical manifestations and laboratory findings of IIMs, discusses the efficiency of modern and standard methods employed in their workup, and delineates optimal practice for clinical care. Α multidisciplinary diagnostic approach that combines clinical, neurologic and rheumatologic examination, evaluation of electrophysiologic and morphologic muscle characteristics, and assessment of autoantibody immunoassays has been determined to be the preferred approach for effective management of patients with suspected IIMs.
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Affiliation(s)
- Konstantinos I Tsamis
- Department of Neurology, University Hospital of Ioannina, Ioannina, Greece.,School of Medicine, European University Cyprus, Nicosia, Cyprus.,Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | | | | | | | - Ilias P Nikas
- School of Medicine, European University Cyprus, Nicosia, Cyprus
| | - Yannis V Simos
- Department of Physiology, Faculty of Medicine, School of Health Sciences, University of Ioannina, Ioannina, Greece
| | | | - Ioannis Sarmas
- Department of Neurology, University Hospital of Ioannina, Ioannina, Greece
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17
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Abstract
PURPOSE OF REVIEW This is a comprehensive review of the current knowledge on predominant immune cell phenotypes involved in idiopathic inflammatory myopathies (IIM). RECENT FINDINGS Major circulating immune cell subpopulations described in IIM encompass the lymphocyte compartment. An unbalance in T cell subsets seems to consistently affect the peripheral and muscle compartment, with a predominance of CD4+ T and B cells in dermatomyositis, CD8+ T cells in polymyositis/inclusion body myositis (IBM) and novel findings highlighting novel proinflammatory T subsets, that is, CD8+Tbet+ and CD28- T cells across different IIM subsets. On the other hand, an impairment in Treg cells number and function has been described especially across polymyositis/dermatomyositis and IBM. Total T follicular helper (Tfh) cells, increased in immune-mediated necrotizing myopathy, skewed toward Tfh2 and Tfh17 in dermatomyositis, polymyositis, and juvenile dermatomyositis. B cell compartment is more rarely described in IIM, yet an unbalance in this pool is as well likely. Evidence of plasma cells increased in polymyositis, dermatomyositis, IBM, and Bregs decreased in dermatomyositis have been reported. Perturbations in the memory and naïve subsets are common in dermatomyositis/polymyositis and antisynthetase syndrome. SUMMARY Protean immune cell abnormalities characterize different IIM subsets, reflecting the complexity of these autoimmune conditions. A deeper understanding of B-cell and T-cell immunophenotyping may promote early diagnosis and identification of new potential therapeutic targets.
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18
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Mukkera S, Ammu A, Bare S, Alahari LP, Naramala S. Unusual Bilateral Upper Extremity Pitting Edema in a Patient With Severe Dermatomyositis. Cureus 2021; 13:e15445. [PMID: 34113527 PMCID: PMC8177094 DOI: 10.7759/cureus.15445] [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: 11/05/2022] Open
Abstract
A 56-year-old Hispanic female presented with six weeks of progressive dysphagia, proximal muscle weakness, erythematous rash, bilateral upper extremity pitting edema, and left lower extremity pitting edema. She had preserved heart function and a normal echocardiogram (ECG). She presented with elevated creatine kinase (CK) and aldolase, with normal renal function. Muscle biopsy suggested idiopathic polymyositis. No blood clot was seen on deep vein thrombosis (DVT) ultrasound. The myositis antibody panel showed the NXP-2 antibody, which is usually seen in pediatric dermatomyositis cases. In our literature search, extremity pitting edema is an unusual way of presentation in dermatomyositis. She responded with intravenous immunoglobulin (IVIg) and high-dose intravenous steroids. We used azathioprine for remission maintenance; her rash recurred after tapering steroids. We resumed tapering steroid therapy and started her on weekly methotrexate along with daily azathioprine. With this combination therapy, her rash and muscle function improved. We successfully tapered her steroids. In our literature search, combination therapy with azathioprine and methotrexate was not reported. Our patient is tolerating this therapy very well.
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Affiliation(s)
- Srikanth Mukkera
- Rheumatology, Texas Tech University Health Sciences Center at Permian Basin, Odessa, USA
| | - Anusha Ammu
- Internal Medicine, Texas Tech University Health Sciences Center at Permian Basin, Odessa, USA
| | - Sudhir Bare
- Hospital Medicine, Medical Center Hospital, Odessa, USA
| | - Lakshmi P Alahari
- Internal Medicine, Texas Tech University Health Sciences Center at Permian Basin, Odessa, USA
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19
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Zhao L, Wang Q, Zhou B, Zhang L, Zhu H. The Role of Immune Cells in the Pathogenesis of Idiopathic Inflammatory Myopathies. Aging Dis 2021; 12:247-260. [PMID: 33532139 PMCID: PMC7801271 DOI: 10.14336/ad.2020.0410] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 04/10/2020] [Indexed: 12/15/2022] Open
Abstract
Idiopathic inflammatory myopathies (IIMs) are chronic autoimmune disorders involving multiple organs, such as the muscle, skin, lungs and joints. Although the detailed pathogenesis of IIMs remains unclear, immune mechanisms have long been recognised as of key importance. Immune cells contribute to many inflammatory processes via intercellular interactions and secretion of inflammatory factors, and many studies have demonstrated the participation of a variety of immune cells, such as T cells and B cells, in the development of IIMs. Here, we summarise the current knowledge regarding immune cells in IIM patients and discuss their potential roles in IIM pathogenesis.
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Affiliation(s)
- Lijuan Zhao
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
| | - Qi Wang
- Department of Radiology, Hunan Provincial People's Hospital and The First Affiliated Hospital of Hunan Normal University, Changsha, Hunan, China.
| | - Bin Zhou
- Department of Nephrology, The Affiliated Hospital of Qingdao University, Qingdao, China.
| | - Lihua Zhang
- Department of Rheumatology, Hunan Provincial People's Hospital and The First Affiliated Hospital of Hunan Normal University, Changsha, Hunan, China.
| | - Honglin Zhu
- Department of Rheumatology, Xiangya Hospital, Central South University, Changsha, Hunan, China.
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20
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Young-Glazer J, Cisneros A, Wilfong EM, Smith SA, Crofford LJ, Bonami RH. Jo-1 autoantigen-specific B cells are skewed towards distinct functional B cell subsets in anti-synthetase syndrome patients. Arthritis Res Ther 2021; 23:33. [PMID: 33468230 PMCID: PMC7814460 DOI: 10.1186/s13075-020-02412-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 12/29/2020] [Indexed: 12/17/2022] Open
Abstract
Background Anti-Jo-1 autoantibodies which recognize histidyl-tRNA synthetase identify patients with the rare rheumatologic disease, anti-histidyl-tRNA synthetase syndrome (Jo-1 ARS), a phenotypically distinct subset of idiopathic inflammatory myopathies (IIM). Jo-1-binding B cells (JBCs) are implicated in disease pathogenesis, yet they have not been studied directly. We therefore aimed to characterize JBCs to better understand how they expand and function in Jo-1 ARS. Methods We enrolled 10 IIM patients diagnosed with Jo-1 ARS, 4 patients with non-Jo-1 IIM, and 8 age- and sex-matched healthy controls. We phenotypically characterized peripheral blood mononuclear cells (PBMCs) ex vivo using flow cytometry to define the B cell subsets in which JBCs reside. We further tested their ability to differentiate into antibody-secreting cells following stimulation in vitro. Results The majority of JBCs were IgM+ (not class-switched). Compared to non-JBCs in the same donors, JBCs contained a higher percentage of autoimmune-prone CD21lo cells and were increased in the CD21lo IgM+ IgD− CD27+ memory subset relative to healthy donor B cells. Whereas non-JBCs were present in the anergic BND B cell subset, JBCs were nearly absent from this compartment. JBCs were detected among plasmablasts in some donors, but a reduced frequency of JBCs differentiated into CD38hi24− plasmablasts compared to non-JBCs present in the same wells following in vitro stimulation. Conclusions JBCs are enriched for autoimmune-prone CD21lo B cells, some of which exhibit a memory phenotype in the peripheral repertoire of Jo-1 ARS patients. JBCs undergo limited class switch and show reduced capacity to differentiate into antibody-secreting cells. This suggests complex B cell biology exists beyond class-switched cells that differentiate to secrete anti-Jo-1 autoantibody (i.e., what is captured through serum autoantibody studies). New Jo-1 ARS therapies should thus ideally target non-class-switched JBCs in addition to those that have undergone IgG class-switching to most effectively block cross-talk with autoreactive T cells. Supplementary Information The online version contains supplementary material available at 10.1186/s13075-020-02412-8.
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Affiliation(s)
- Jennifer Young-Glazer
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Medical Center North T3113, 1161 21st Avenue South, Nashville, TN, 37232, USA
| | - Alberto Cisneros
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Medical Center North T3113, 1161 21st Avenue South, Nashville, TN, 37232, USA
| | - Erin M Wilfong
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Medical Center North T3113, 1161 21st Avenue South, Nashville, TN, 37232, USA.,Department of Medicine, Division of Allergy, Pulmonary, and Critical Care, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Scott A Smith
- Department of Medicine, Division of Infectious Diseases, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Leslie J Crofford
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Medical Center North T3113, 1161 21st Avenue South, Nashville, TN, 37232, USA.,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA
| | - Rachel H Bonami
- Department of Medicine, Division of Rheumatology and Immunology, Vanderbilt University Medical Center, Medical Center North T3113, 1161 21st Avenue South, Nashville, TN, 37232, USA. .,Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center, Nashville, TN, 37232, USA.
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21
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Dalakas MC. Inflammatory myopathies: update on diagnosis, pathogenesis and therapies, and COVID-19-related implications. ACTA MYOLOGICA : MYOPATHIES AND CARDIOMYOPATHIES : OFFICIAL JOURNAL OF THE MEDITERRANEAN SOCIETY OF MYOLOGY 2020; 39:289-301. [PMID: 33458584 PMCID: PMC7783437 DOI: 10.36185/2532-1900-032] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/09/2020] [Accepted: 11/09/2020] [Indexed: 12/11/2022]
Abstract
The inflammatory myopathies constitute a heterogeneous group of acquired myopathies that have in common the presence of endomysial inflammation. Based on steadily evolved clinical, histological and immunopathological features and some autoantibody associations, these disorders can now be classified in five characteristic subsets: Dermatomyositis (DM) Polymyositis (PM), Necrotizing Autoimmune Myositis (NAM), Anti-synthetase syndrome-overlap myositis (Anti-SS-OM), and Inclusion-Body-Myositis (IBM). Each inflammatory myopathy subset has distinct immunopathogenesis, prognosis and response to immunotherapies, necessitating the need to correctly identify each subtype from the outset to avoid disease mimics and proceed to early therapy initiation. The review presents the main clinicopathologic characteristics of each subset highlighting the importance of combining expertise in clinical neurological examination with muscle morphology and immunopathology to avoid erroneous diagnoses and therapeutic schemes. The main autoimmune markers related to autoreactive T cells, B cells, autoantibodies and cytokines are presented and the concomitant myodegenerative features seen in IBM muscles are pointed out. Most importantly, unsettled issues related to a role of autoantibodies and controversies with reference to possible triggering factors related to statins are clarified. The emerging effect SARS-CoV-2 as the cause of hyperCKemia and potentially NAM is addressed and practical guidelines on the best therapeutic approaches and concerns regarding immunotherapies during COVID-19 pandemic are summarized.
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Affiliation(s)
- Marinos C Dalakas
- Department of Neurology, Thomas Jefferson University, Philadelphia, PA USA and the Neuroimmunology Unit, National and Kapodistrian University University of Athens Medical School, Athens, Greece
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Greenberg SA. Inclusion body myositis: clinical features and pathogenesis. Nat Rev Rheumatol 2020; 15:257-272. [PMID: 30837708 DOI: 10.1038/s41584-019-0186-x] [Citation(s) in RCA: 166] [Impact Index Per Article: 33.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Inclusion body myositis (IBM) is often viewed as an enigmatic disease with uncertain pathogenic mechanisms and confusion around diagnosis, classification and prospects for treatment. Its clinical features (finger flexor and quadriceps weakness) and pathological features (invasion of myofibres by cytotoxic T cells) are unique among muscle diseases. Although IBM T cell autoimmunity has long been recognized, enormous attention has been focused for decades on several biomarkers of myofibre protein aggregates, which are present in <1% of myofibres in patients with IBM. This focus has given rise, together with the relative treatment refractoriness of IBM, to a competing view that IBM is not an autoimmune disease. Findings from the past decade that implicate autoimmunity in IBM include the identification of a circulating autoantibody (anti-cN1A); the absence of any statistically significant genetic risk factor other than the common autoimmune disease 8.1 MHC haplotype in whole-genome sequencing studies; the presence of a marked cytotoxic T cell signature in gene expression studies; and the identification in muscle and blood of large populations of clonal highly differentiated cytotoxic CD8+ T cells that are resistant to many immunotherapies. Mounting evidence that IBM is an autoimmune T cell-mediated disease provides hope that future therapies directed towards depleting these cells could be effective.
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Affiliation(s)
- Steven A Greenberg
- Department of Neurology, Brigham and Women's Hospital, Boston, MA, USA. .,Children's Hospital Computational Health Informatics Program, Boston Children's Hospital, Boston, MA, USA. .,Harvard Medical School, Boston, MA, USA.
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Yang SH, Chang C, Lian ZX. Polymyositis and dermatomyositis - challenges in diagnosis and management. J Transl Autoimmun 2019; 2:100018. [PMID: 32743506 PMCID: PMC7388349 DOI: 10.1016/j.jtauto.2019.100018] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 10/04/2019] [Indexed: 02/06/2023] Open
Abstract
Polymyositis (PM) and dermatomyositis (DM) are different disease subtypes of idiopathic inflammatory myopathies (IIMs). The main clinical features of PM and DM include progressive symmetric, predominantly proximal muscle weakness. Laboratory findings include elevated creatine kinase (CK), autoantibodies in serum, and inflammatory infiltrates in muscle biopsy. Dermatomyositis can also involve a characteristic skin rash. Both polymyositis and dermatomyositis can present with extramuscular involvement. The causative factor is agnogenic activation of immune system, leading to immunologic attacks on muscle fibers and endomysial capillaries. The treatment of choice is immunosuppression. PM and DM can be distinguished from other IIMs and myopathies by thorough history, physical examinations and laboratory evaluation and adherence to specific and up-to-date diagnosis criteria and classification standards. Treatment is based on correct diagnosis of these conditions. Challenges of diagnosis and management influences the clinical research and practice of Polymyositis and dermatomyositis. Diagnostic criteria have been updated and novel therapies have been developed in PM/DM. Pathogenesis investigation and diagnosis precision improvement may help to guide future treatment strategies.
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Key Words
- APC, antigen presenting cell
- AZA, Azathioprine
- CAM, cancer associated myositis
- CK, creatine kinase
- DM, dermatomyositis
- Dermatomyositis
- Diagnosis criteria
- EMG, electromyography
- HLA, human leukocyte antigen
- IIM, idiopathic inflammatory myopathies
- ILD, interstitial lung disease
- IV, intravenous
- Idiopathic inflammatory myopathy
- JDM, juvenile dermatomyositis
- MAA, myositis associated antibody
- MAC, membrane attack complex
- MHC, major histocompatibility complex
- MMF, mycophenolate mofetil
- MRI, magnetic resonance imaging
- MSA, myositis specific antibody
- MTX, methotrexate
- MUAP, motor unit action potential
- NAM, necrotizing autoimmune myopathy
- PM, polymyositis
- Polymyositis
- TNF, tumor necrosis factor
- Treatment
- Treg, regulatory T cell
- UVR, ultraviolet radiation
- sIBM, sporadic inclusion body myositis
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Affiliation(s)
- Shu-Han Yang
- Chronic Disease Laboratory, Institutes for Life Sciences and School of Medicine, South China University of Technology, Guangzhou, 510006, China
| | - Christopher Chang
- Division of Rheumatology, Allergy and Clinical Immunology, University of California, Davis, Davis, CA, USA.,Division of Pediatric Immunology and Allergy, Joe DiMaggio Children's Hospital, Hollywood, FL, USA
| | - Zhe-Xiong Lian
- Chronic Disease Laboratory, Institutes for Life Sciences and School of Medicine, South China University of Technology, Guangzhou, 510006, China
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Kirpach J, Colone A, Bürckert JP, Faison WJ, Dubois ARSX, Sinner R, Reye AL, Muller CP. Detection of a Low Level and Heterogeneous B Cell Immune Response in Peripheral Blood of Acute Borreliosis Patients With High Throughput Sequencing. Front Immunol 2019; 10:1105. [PMID: 31156648 PMCID: PMC6532064 DOI: 10.3389/fimmu.2019.01105] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2018] [Accepted: 04/30/2019] [Indexed: 01/08/2023] Open
Abstract
The molecular diagnosis of acute Borreliosis is complicated and better strategies to improve the diagnostic processes are warranted. High Throughput Sequencing (HTS) of human B cell repertoires after e.g., Dengue virus infection or influenza vaccination revealed antigen-associated “CDR3 signatures” which may have the potential to support diagnosis in infectious diseases. The human B cell immune response to Borrelia burgdorferi sensu lato—the causative agent of Borreliosis—has mainly been studied at the antibody level, while less attention has been given to the cellular part of the humoral immune response. There are indications that Borrelia actively influence the B cell immune response and that it is therefore not directly comparable to responses induced by other infections. The main goal of this study was to identify B cell features that could be used to support diagnosis of Borreliosis. Therefore, we characterized the B cell immune response in these patients by combining multicolor flow cytometry, single Borrelia-reactive B cell receptor (BCR) sequencing, and B cell repertoire deep sequencing. Our phenotyping experiments showed, that there is no significant difference between B cell subpopulations of acute Borreliosis patients and controls. BCR sequences from individual epitope-reactive B cells had little in common between each other. HTS showed, however, a higher complementarity determining region 3 (CDR3) amino acid (aa) sequence overlap between samples from different timepoints in patients as compared to controls. This indicates, that HTS is sensitive enough to detect ongoing B cell immune responses in these patients. Although each individual's repertoire was dominated by rather unique clones, clustering of bulk BCR repertoire sequences revealed a higher overlap of IgG BCR repertoire sequences between acute patients than controls. Even if we have identified a few Borrelia-associated CDR3aa sequences, they seem to be rather unique for each patient and therefore not suitable as biomarkers.
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Affiliation(s)
- Josiane Kirpach
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Alessia Colone
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Jean-Philippe Bürckert
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - William J Faison
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Axel R S X Dubois
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Regina Sinner
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Anna L Reye
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
| | - Claude P Muller
- Vaccinology and B Cell Immunology, Infectious Diseases Research Unit, Department of Infection and Immunity, Luxembourg Institute of Health, Esch-sur-Alzette, Luxembourg
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Emmer A, Abobarin-Adeagbo A, Posa A, Jordan B, Delank KS, Staege MS, Surov A, Zierz S, Kornhuber ME. Myositis in Lewis rats induced by the superantigen Staphylococcal enterotoxin A. Mol Biol Rep 2019; 46:4085-4094. [DOI: 10.1007/s11033-019-04858-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 05/03/2019] [Indexed: 12/18/2022]
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Naddaf E, Barohn RJ, Dimachkie MM. Inclusion Body Myositis: Update on Pathogenesis and Treatment. Neurotherapeutics 2018; 15:995-1005. [PMID: 30136253 PMCID: PMC6277289 DOI: 10.1007/s13311-018-0658-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Inclusion body myositis is the most common acquired myopathy after the age of 50. It is characterized by progressive asymmetric weakness predominantly affecting the quadriceps and/or finger flexors. Loss of ambulation and dysphagia are major complications of the disease. Inclusion body myositis can be associated with cytosolic 5'-nucleotidase 1A antibodies. Muscle biopsy usually shows inflammatory cells surrounding and invading non-necrotic muscle fibers, rimmed vacuoles, congophilic inclusions, and protein aggregates. Disease pathogenesis remains poorly understood and consists of an interplay between inflammatory and degenerative pathways. Antigen-driven, clonally restricted, cytotoxic T cells represent a main feature of the inflammatory component, whereas abnormal protein homeostasis with protein misfolding, aggregation, and dysfunctional protein disposal is the hallmark of the degenerative component. Inclusion body myositis remains refractory to treatment. Better understanding of the disease pathogenesis led to the identification of novel therapeutic targets, addressing both the inflammatory and degenerative pathways.
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Affiliation(s)
- Elie Naddaf
- Neuromuscular Medicine Division, Department of Neurology, Mayo Clinic, Rochester, Minnesota, 55905, USA
| | - Richard J Barohn
- Neuromuscular Medicine Division, Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, 66103, USA
| | - Mazen M Dimachkie
- Neuromuscular Medicine Division, Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, 66103, USA.
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Herbelet S, De Bleecker JL. Immune checkpoint failures in inflammatory myopathies: An overview. Autoimmun Rev 2018; 17:746-754. [PMID: 29885538 DOI: 10.1016/j.autrev.2018.01.026] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2018] [Accepted: 01/18/2018] [Indexed: 12/21/2022]
Abstract
Dermatomyositis (DM), polymyositis (PM), inclusion body myositis (IBM), immune mediated necrotizing myopathy (IMNM) and overlap myositis (OM) are classified as inflammatory myopathies (IM) with involvement of autoimmune features such as autoreactive lymphocytes and autoantibodies. Autoimmunity can be defined as a loss in self-tolerance and attack of autoantigens by the immune system. Self-tolerance is achieved by a group of immune mechanisms occurring in central and periphal lymphoid organs and tissues, called immune checkpoints, that work in synergy to protect the body from harmful immune reactions. Autoimmune disorders appear when immune checkpoints fail. In this review, the different immune checkpoint failures are discussed in DM, PM, IBM and IMNM. Exploring research contribution in each of these immune checkpoints might help to highlight research perspectives in the field and obtain a more complete picture of IM disease pathology.
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Affiliation(s)
- Sandrine Herbelet
- Department of Neurology, Ghent University and Ghent University Hospital, C. Heymanslaan 10, 9000 Gent, Belgium.
| | - Jan L De Bleecker
- Department of Neurology, Ghent University and Ghent University Hospital, C. Heymanslaan 10, 9000 Gent, Belgium
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Abstract
Inflammatory disorders of the skeletal muscle include polymyositis (PM), dermatomyositis (DM), (immune mediated) necrotizing myopathy (NM), overlap syndrome with myositis (overlap myositis, OM) including anti-synthetase syndrome (ASS), and inclusion body myositis (IBM). Whereas DM occurs in children and adults, all other forms of myositis mostly develop in middle aged individuals. Apart from a slowly progressive, chronic disease course in IBM, patients with myositis typically present with a subacute onset of weakness of arms and legs, often associated with pain and clearly elevated creatine kinase in the serum. PM, DM and most patients with NM and OM usually respond to immunosuppressive therapy, whereas IBM is largely refractory to treatment. The diagnosis of myositis requires careful and combinatorial assessment of (1) clinical symptoms including pattern of weakness and paraclinical tests such as MRI of the muscle and electromyography (EMG), (2) broad analysis of auto-antibodies associated with myositis, and (3) detailed histopathological work-up of a skeletal muscle biopsy. This review provides a comprehensive overview of the current classification, diagnostic pathway, treatment regimen and pathomechanistic understanding of myositis.
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Affiliation(s)
- Jens Schmidt
- Department of Neurology, Muscle Immunobiology Group, Neuromuscular Center, University Medical Center Göttingen, Göttingen, Germany,Correspondence to: Prof. Dr. Jens Schmidt, MD, FEAN, FAAN, Muscle Immunobiology Group, Neuromuscular Center, Department of Neurology, University Medical Center Göttingen, Robert-Koch-Str. 40, 37075 Göttingen, Germany. Tel.: +49 551 39 22355; Fax: +49 551 39 8405; E-mail:
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Abstract
Autoimmune diseases develop as a result of chronic inflammation owing to interactions between genes and the environment. However, the mechanisms by which autoimmune diseases evolve remain poorly understood. Newly discovered risk factors and pathogenic processes in the various idiopathic inflammatory myopathy (IIM) phenotypes (known collectively as myositis) have illuminated innovative approaches for understanding these diseases. The HLA 8.1 ancestral haplotype is a key risk factor for major IIM phenotypes in some populations, and several genetic variants associated with other autoimmune diseases have been identified as IIM risk factors. Environmental risk factors are less well studied than genetic factors but might include viruses, bacteria, ultraviolet radiation, smoking, occupational and perinatal exposures and a growing list of drugs (including biologic agents) and dietary supplements. Disease mechanisms vary by phenotype, with evidence of shared innate and adaptive immune and metabolic pathways in some phenotypes but unique pathways in others. The heterogeneity and rarity of the IIMs make advancements in diagnosis and treatment cumbersome. Novel approaches, better-defined phenotypes, and international, multidisciplinary consensus have contributed to progress, and it is hoped that these methods will eventually enable therapeutic intervention before the onset or major progression of disease. In the future, preemptive strategies for IIM management might be possible.
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Affiliation(s)
- Frederick W. Miller
- Environmental Autoimmunity Group, Clinical Research Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC, USA
| | - Janine A. Lamb
- Centre for Epidemiology, Faculty of Biology, Medicine and Health, Manchester Academic Health Science Centre, The University of Manchester, UK
| | - Jens Schmidt
- Department of Neurology, University Medical Center Göttingen, Göttingen, Germany
| | - Kanneboyina Nagaraju
- Department of Pharmaceutical Sciences, School of Pharmacy and Pharmaceutical Sciences, Binghamton University, Binghamton, NY, USA
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Anan R, Akiyama M, Kaneko Y, Kikuchi J, Suzuki K, Matsubara S, Takeuchi T. Polymyositis with elevated serum IgG4 levels and abundant IgG4+ plasma cell infiltration: A case report and literature review. Medicine (Baltimore) 2017; 96:e8710. [PMID: 29310344 PMCID: PMC5728745 DOI: 10.1097/md.0000000000008710] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
INTRODUCTION Polymyositis (PM) is a type of autoimmune, inflammatory myopathy. IgG4-related disease (IgG4-RD) is a recently recognized disease entity characterized by elevated serum IgG4 levels and IgG4 plasma-cell infiltration of various organs. However, several reports have described cases of other diseases that present with those features, suggesting the importance of careful differential diagnosis. Herein, we report the first case of PM with elevated serum IgG4 levels and IgG4 plasma cells in the muscles, mimicking IgG4-RD.A 73-year-old woman visited our hospital because of proximal muscle weakness of both thighs. Her blood test showed high levels of serum creatinine kinase, aldolase, and IgG4. Magnetic resonance imaging of the thighs showed muscle edema. Needle electromyography showed findings typical of myositis. Histological analysis of her left quadriceps revealed infiltration of IgG4 plasma cells as well as CD8 T cells. Scattered necrotic and regenerating muscle fibers with no specific findings for IgG4-RD (storiform fibrosis and obliterative phlebitis) were typical for PM. We diagnosed her condition as PM and treated her with 40 mg/day of prednisolone that decreased levels of muscle enzymes and improved muscle weakness. CONCLUSION Our case indicated that PM could present with high serum IgG4 levels and IgG4 plasma-cell infiltration, mimicking IgG4-RD. Although the mechanism of IgG4 elevation in such PM is unclear, our case highlights the necessity to recognize that high serum IgG4 levels and IgG4 plasma-cell infiltration in organs are not specific for IgG4-RD.
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Affiliation(s)
- Ryusuke Anan
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
| | - Mitsuhiro Akiyama
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
| | - Yuko Kaneko
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
| | - Jun Kikuchi
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
| | - Kazuko Suzuki
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
| | - Shiro Matsubara
- Department of Neurology, Tokyo Metropolitan Neurological Hospital, Tokyo, Japan
| | - Tsutomu Takeuchi
- Division of Rheumatology, Department of Internal Medicine, Keio University School of Medicine
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Keller CW, Schmidt J, Lünemann JD. Immune and myodegenerative pathomechanisms in inclusion body myositis. Ann Clin Transl Neurol 2017; 4:422-445. [PMID: 28589170 PMCID: PMC5454400 DOI: 10.1002/acn3.419] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Revised: 04/09/2017] [Accepted: 04/10/2017] [Indexed: 12/17/2022] Open
Abstract
Inclusion Body Myositis (IBM) is a relatively common acquired inflammatory myopathy in patients above 50 years of age. Pathological hallmarks of IBM are intramyofiber protein inclusions and endomysial inflammation, indicating that both myodegenerative and inflammatory mechanisms contribute to its pathogenesis. Impaired protein degradation by the autophagic machinery, which regulates innate and adaptive immune responses, in skeletal muscle fibers has recently been identified as a potential key pathomechanism in IBM. Immunotherapies, which are successfully used for treating other inflammatory myopathies lack efficacy in IBM and so far no effective treatment is available. Thus, a better understanding of the mechanistic pathways underlying progressive muscle weakness and atrophy in IBM is crucial in identifying novel promising targets for therapeutic intervention. Here, we discuss recent insights into the pathomechanistic network of mutually dependent inflammatory and degenerative events during IBM.
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Affiliation(s)
- Christian W. Keller
- Institute of Experimental ImmunologyLaboratory of NeuroinflammationUniversity of ZürichZürichSwitzerland
| | - Jens Schmidt
- Department of NeurologyUniversity Medical Center GöttingenGöttingenGermany
| | - Jan D. Lünemann
- Institute of Experimental ImmunologyLaboratory of NeuroinflammationUniversity of ZürichZürichSwitzerland
- Department of NeurologyUniversity Hospital ZürichZürichSwitzerland
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Needham M, Mastaglia F. Advances in inclusion body myositis: genetics, pathogenesis and clinical aspects. Expert Opin Orphan Drugs 2017. [DOI: 10.1080/21678707.2017.1318056] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Affiliation(s)
- Steven A. Greenberg
- Department of Neurology, Brigham and Women's Hospital; Children's Hospital Informatics Program, and Harvard Medical School; Boston MA
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Bombardieri M, Lewis M, Pitzalis C. Ectopic lymphoid neogenesis in rheumatic autoimmune diseases. Nat Rev Rheumatol 2017; 13:141-154. [PMID: 28202919 DOI: 10.1038/nrrheum.2016.217] [Citation(s) in RCA: 168] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Ectopic lymphoid neogenesis often occurs in the target tissues of patients with chronic rheumatic autoimmune diseases such as rheumatoid arthritis, Sjögren syndrome and other connective tissue disorders, including systemic lupus erythematosus and myositis. However, the mechanisms of ectopic lymphoid-like structure (ELS) formation and function are not entirely understood. For example, it is unclear whether ELSs indicate distinct disease phenotypes or whether they are evolutionary manifestations of chronic inflammation. Also unclear is why ELSs form in some patients but not in others. Nonetheless, ELSs frequently display functional features of ectopic germinal centres and can actively contribute to the maintenance of autoimmunity through the production of disease-specific autoantibodies; furthermore, they seem to influence disease severity and response to both synthetic and biologic DMARDs. In this Review, we discuss current knowledge and gaps in understanding of ELS formation and function including their prevalence in the above rheumatic autoimmune diseases; the mechanisms underlying their formation, maintenance and function, including positive and negative regulatory pathways; their functional relevance in the perpetuation of autoimmunity; their relationship with disease phenotypes, clinical outcomes and response to treatment; and the potential for specific targeting of ELSs through novel therapeutic modalities.
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Affiliation(s)
- Michele Bombardieri
- Centre for Experimental Medicine and Rheumatology, John Vane Science Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Myles Lewis
- Centre for Experimental Medicine and Rheumatology, John Vane Science Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
| | - Costantino Pitzalis
- Centre for Experimental Medicine and Rheumatology, John Vane Science Centre, William Harvey Research Institute, Barts and the London School of Medicine and Dentistry, Queen Mary University of London, Charterhouse Square, London EC1M 6BQ, UK
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Ceribelli A, De Santis M, Isailovic N, Gershwin ME, Selmi C. The Immune Response and the Pathogenesis of Idiopathic Inflammatory Myositis: a Critical Review. Clin Rev Allergy Immunol 2017; 52:58-70. [PMID: 26780034 DOI: 10.1007/s12016-016-8527-x] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The pathogenesis of idiopathic inflammatory myositis (IIMs, including polymyositis and dermatomyositis) remains largely enigmatic, despite advances in the study of the role played by innate immunity, adaptive immunity, genetic predisposition, and environmental factors in an orchestrated response. Several factors are involved in the inflammatory state that characterizes the different forms of IIMs which share features and mechanisms but are clearly different with respect to the involved sites and characteristics of the inflammation. Cellular and non-cellular mechanisms of both the immune and non-immune systems have been identified as key regulators of inflammation in polymyositis/dermatomyositis, particularly at different stages of disease, leading to the fibrotic state that characterizes the end stage. Among these, a special role is played by an interferon signature and complement cascade with different mechanisms in polymyositis and dermatomyositis; these differences can be identified also histologically in muscle biopsies. Numerous cellular components of the adaptive and innate immune response are present in the site of tissue inflammation, and the complexity of idiopathic inflammatory myositis is further supported by the involvement of non-immune mechanisms such as hypoxia and autophagy. The aim of this comprehensive review is to describe the major pathogenic mechanisms involved in the onset of idiopathic inflammatory myositis and to report on the major working hypothesis with therapeutic implications.
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Affiliation(s)
- Angela Ceribelli
- Division of Rheumatology and Clinical Immunology, Humanitas Research Hospital, via A. Manzoni 56, 20089, Rozzano, MI, Italy
- BIOMETRA Department, University of Milan, Milan, Italy
| | - Maria De Santis
- Division of Rheumatology and Clinical Immunology, Humanitas Research Hospital, via A. Manzoni 56, 20089, Rozzano, MI, Italy
| | - Natasa Isailovic
- Division of Rheumatology and Clinical Immunology, Humanitas Research Hospital, via A. Manzoni 56, 20089, Rozzano, MI, Italy
| | - M Eric Gershwin
- Division of Rheumatology, Allergy, and Clinical Immunology, University of California Davis, Davis, CA, USA
| | - Carlo Selmi
- Division of Rheumatology and Clinical Immunology, Humanitas Research Hospital, via A. Manzoni 56, 20089, Rozzano, MI, Italy.
- BIOMETRA Department, University of Milan, Milan, Italy.
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Truffault F, de Montpreville V, Eymard B, Sharshar T, Le Panse R, Berrih-Aknin S. Thymic Germinal Centers and Corticosteroids in Myasthenia Gravis: an Immunopathological Study in 1035 Cases and a Critical Review. Clin Rev Allergy Immunol 2017; 52:108-124. [PMID: 27273086 DOI: 10.1007/s12016-016-8558-3] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The most common form of Myasthenia gravis (MG) is due to anti-acetylcholine receptor (AChR) antibodies and is frequently associated with thymic pathology. In this review, we discuss the immunopathological characteristics and molecular mechanisms of thymic follicular hyperplasia, the effects of corticosteroids on this thymic pathology, and the role of thymic epithelial cells (TEC), a key player in the inflammatory thymic mechanisms. This review is based not only on the literature data but also on thymic transcriptome results and analyses of pathological and immunological correlations in a vast cohort of 1035 MG patients without thymoma. We show that among patients presenting a thymic hyperplasia with germinal centers (GC), 80 % are females, indicating that thymic follicular hyperplasia is mainly a disease of women. The presence of anti-AChR antibodies is correlated with the degree of follicular hyperplasia, suggesting that the thymus is a source of anti-AChR antibodies. The degree of hyperplasia is not dependent upon the time from the onset, implying that either the antigen is chronically expressed and/or that the mechanisms of the resolution of the GC are not efficiently controlled. Glucocorticoids, a conventional therapy in MG, induce a significant reduction in the GC number, together with changes in the expression of chemokines and angiogenesis. These changes are likely related to the acetylation molecular process, overrepresented in corticosteroid-treated patients, and essential for gene regulation. Altogether, based on the pathological and molecular thymic abnormalities found in MG patients, this review provides some explanations for the benefit of thymectomy in early-onset MG patients.
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Affiliation(s)
- Frédérique Truffault
- INSERM U974, Paris, France.,CNRS FRE3617, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,AIM, Institut de myologie, Paris, France
| | | | - Bruno Eymard
- Department of Neuromuscular Disorders, CHU Salpêtrière, Paris, France
| | - Tarek Sharshar
- General Intensive Care Medicine, Assistance Publique Hôpitaux de Paris, Raymond Poincaré Hospital, University of Versailles Saint-Quentin en Yvelines, 92380, Garches, France
| | - Rozen Le Panse
- INSERM U974, Paris, France.,CNRS FRE3617, Paris, France.,Sorbonne Universités, UPMC Univ Paris 06, Paris, France.,AIM, Institut de myologie, Paris, France
| | - Sonia Berrih-Aknin
- INSERM U974, Paris, France. .,CNRS FRE3617, Paris, France. .,Sorbonne Universités, UPMC Univ Paris 06, Paris, France. .,AIM, Institut de myologie, Paris, France. .,UMRS 974 UPMC, INSERM, FRE 3617 CNRS, AIM, Center of Research in Myology, 105 Boulevard de l'Hôpital, Paris, 75013, France.
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Abstract
PURPOSE OF REVIEW Inclusion body myositis (IBM) is an enigmatic progressive disease of skeletal muscle. This review provides a summary of the clinical and pathophysiologic aspects of IBM. RECENT FINDINGS The development of diagnostic blood testing for IBM followed from the discovery of a B-cell pathway in IBM muscle and circulating autoantibodies against NT5C1A, further establishing IBM's status as an autoimmune disease. The key role of cytotoxic T cells in IBM is further supported by the identification of a link between IBM and T-cell large granular lymphocytic leukemia. The testing of research diagnostic criteria in patients is improving its accuracy. Increases in estimated prevalences may be due to a combination of true increases and improved recognition of disease. SUMMARY IBM has high unmet medical need. Advances in the mechanistic understanding of IBM as an autoimmune disease will drive effective therapeutic approaches. The identification of a B-cell pathway has resulted in the first identification of an IBM autoantigen and emphasized its status as an autoimmune disease. The recognition that large granular lymphocyte CD8+ T-cell expansions are present in both blood and muscle provides additional biomarkers for IBM and suggests a mechanistic relationship to the neoplastic disease T-cell large granular lymphocytic leukemia.
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Goyal NA, Cash TM, Alam U, Enam S, Tierney P, Araujo N, Mozaffar FH, Pestronk A, Mozaffar T. Seropositivity for NT5c1A antibody in sporadic inclusion body myositis predicts more severe motor, bulbar and respiratory involvement. J Neurol Neurosurg Psychiatry 2016; 87:373-8. [PMID: 25857661 PMCID: PMC6192256 DOI: 10.1136/jnnp-2014-310008] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 03/19/2015] [Indexed: 11/04/2022]
Abstract
OBJECTIVES To explore phenotypic differences between individuals with sporadic inclusion body myositis (sIBM) who are seropositive for the NT5c1A antibody compared with those who are seronegative. METHODS Cross-sectional clinical, serological and functional analysis in 25 consecutive participants with sIBM. RESULTS All participants met criteria for clinically defined or probable sIBM. 18 of 25 participants with sIBM (72%) were seropositive for the NT5c1A antibody. No differences between median age and duration of illness between the two groups were seen. Females have higher odds of being seropositive (OR=2.30). Participants with seropositive sIBM took significantly longer to get up and stand (p=0.012). There were no significant differences between the two groups in terms of distance covered on a 6 min walk. Seropositive participants were more likely to require assistive devices such as a walker or wheelchair for mobility (OR=23.00; p=0.007). A number of secondary (exploratory) outcomes were assessed. NT5c1A seropositive sIBM cases had lower total Medical Research Council (MRC) sum score and MRC sum score on the right (p=0.03 and 0.02, respectively). Participants with the NT5c1A antibody were significantly more likely to have symptoms of dysphagia (OR=10.67; p=0.03) and reduced forced vital capacity (p=0.005). Facial weakness occurred in 50% of seropositive participants while it was only seen in 14% of seronegative participants. CONCLUSIONS Even though the small sample size limits definite conclusions, our cross-sectional study showed seropositivity to the NT5c1A antibody is associated with greater motor and functional disability in sIBM. The study also suggests more prominent bulbar, facial and respiratory involvement in individuals positive for NT5c1A antibodies.
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Affiliation(s)
- N A Goyal
- Department of Neurology, University of California, Irvine, California, USA
| | - T M Cash
- Department of Neurology, University of California, Irvine, California, USA
| | - U Alam
- Department of Neurology, University of California, Irvine, California, USA
| | - S Enam
- Department of Neurology, University of California, Irvine, California, USA
| | - P Tierney
- Department of Neurology, University of California, Irvine, California, USA
| | - N Araujo
- Department of Neurology, University of California, Irvine, California, USA
| | - F H Mozaffar
- Department of Neurology, University of California, Irvine, California, USA
| | - A Pestronk
- Department of Neurology, Washington University, St. Louis, Missouri, USA
- Department of Pathology, Washington University, St. Louis, Missouri, USA
| | - T Mozaffar
- Department of Neurology, University of California, Irvine, California, USA
- Department of Orthopaedic Surgery, University of California, Irvine, California, USA
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Willis SN, Stathopoulos P, Chastre A, Compton SD, Hafler DA, O'Connor KC. Investigating the Antigen Specificity of Multiple Sclerosis Central Nervous System-Derived Immunoglobulins. Front Immunol 2015; 6:600. [PMID: 26648933 PMCID: PMC4663633 DOI: 10.3389/fimmu.2015.00600] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2015] [Accepted: 11/09/2015] [Indexed: 12/25/2022] Open
Abstract
The central nervous system (CNS) of patients with multiple sclerosis (MS) is the site where disease pathology is evident. Damaged CNS tissue is commonly associated with immune cell infiltration. This infiltrate often includes B cells that are found in multiple locations throughout the CNS, including the cerebrospinal fluid (CSF), parenchyma, and the meninges, frequently forming tertiary lymphoid structures in the latter. Several groups, including our own, have shown that B cells from distinct locations within the MS CNS are clonally related and display the characteristics of an antigen-driven response. However, the antigen(s) driving this response have yet to be conclusively defined. To explore the antigen specificity of the MS B cell response, we produced recombinant human immunoglobulin (rIgG) from a series of expanded B cell clones that we isolated from the CNS tissue of six MS brains. The specificity of these MS-derived rIgG and control rIgG derived from non-MS tissues was then examined using multiple methodologies that included testing individual candidate antigens, screening with high-throughput antigen arrays and evaluating binding to CNS-derived cell lines. We report that while several MS-derived rIgG recognized particular antigens, including neurofilament light and a protocadherin isoform, none were unique to MS, as non-MS-derived rIgG used as controls invariably displayed similar binding specificities. We conclude that while MS CNS resident B cells display the characteristics of an antigen-driven B cell response, the antigen(s) driving this response remain at large.
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Affiliation(s)
- Simon N Willis
- Department of Neurology, Yale School of Medicine , New Haven, CT , USA ; Walter and Eliza Hall Institute of Medical Research , Parkville, VIC , Australia ; Department of Medical Biology, University of Melbourne , Parkville, VIC , Australia
| | | | - Anne Chastre
- Department of Neurology, Yale School of Medicine , New Haven, CT , USA
| | - Shannon D Compton
- Department of Neurology, Yale School of Medicine , New Haven, CT , USA
| | - David A Hafler
- Department of Neurology, Yale School of Medicine , New Haven, CT , USA ; Department of Immunobiology, Yale School of Medicine , New Haven, CT , USA
| | - Kevin C O'Connor
- Department of Neurology, Yale School of Medicine , New Haven, CT , USA
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Haq SA, Tournadre A. Idiopathic inflammatory myopathies: from immunopathogenesis to new therapeutic targets. Int J Rheum Dis 2015; 18:818-25. [PMID: 26385431 DOI: 10.1111/1756-185x.12736] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pathogenesis of idiopathic inflammatory myositis (IIM) involves strong interactions between dendritic cells (DCs), activated Th1 and Th17 cells, B cells, muscle cells, genes and environment. Local maturation of DCs permit the activation and polarization of CD4+ T cells into T(H)1 and T(H)17 that play a key role in maintaining chronic muscle inflammation. T-cell mediated myocytotoxicity promotes the liberation of specific muscle autoantigens from regenerating muscle cells with production of myositis-specific autoantibodies. Type I interferon signature is a key characteristic of IIM. Type I IFN that can be induced by immune complexes containing myositis-specific autoantibodies is produced by scattered plasmacytoid DCs but also by muscle cells particularly regenerating muscle cells. These immature muscle precursors appear to be critical in the pathogenesis of IIM as they up-regulate muscle autoantigens, type I IFN, HLA class I antigens and TLR3-7, all together involved in maintaining chronic muscle inflammation. In addition to the role of immune and muscle cells, genome-wide association studies have confirmed the importance of several MHC and non-MHC genes in IIM. Environmental factors can contribute to the pathogenesis of IIM. In sIBM, distinct features suggest both degenerative and inflammatory processes. In addition to our better understanding of the pathogenesis, identify molecular pathway leads to consider new targeted therapies including cytokine inhibition, B-cell and T-cell costimulation blockade, type I IFN neutralization or inhibition of the ubiquitin proteasome pathway.
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Affiliation(s)
- Syed A Haq
- BSM Medical University, Dhaka, Bangladesh
| | - Anne Tournadre
- Rheumatology department CHU Clermont-Ferrand and UMR 1019 INRA/ University of Auvergne, Clermont-Ferrand, France
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Menezes R, Pantelyat A, Izbudak I, Birnbaum J. Movement and Other Neurodegenerative Syndromes in Patients with Systemic Rheumatic Diseases: A Case Series of 8 Patients and Review of the Literature. Medicine (Baltimore) 2015; 94:e0971. [PMID: 26252269 PMCID: PMC4616569 DOI: 10.1097/md.0000000000000971] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Patients with rheumatic diseases can present with movement and other neurodegenerative disorders. It may be underappreciated that movement and other neurodegenerative disorders can encompass a wide variety of disease entities. Such disorders are strikingly heterogeneous and lead to a wider spectrum of clinical injury than seen in Parkinson's disease. Therefore, we sought to stringently phenotype movement and other neurodegenerative disorders presenting in a case series of rheumatic disease patients. We integrated our findings with a review of the literature to understand mechanisms which may account for such a ubiquitous pattern of clinical injury.Seven rheumatic disease patients (5 Sjögren's syndrome patients, 2 undifferentiated connective tissue disease patients) were referred and could be misdiagnosed as having Parkinson's disease. However, all of these patients were ultimately diagnosed as having other movement or neurodegenerative disorders. Findings inconsistent with and more expansive than Parkinson's disease included cerebellar degeneration, dystonia with an alien-limb phenomenon, and nonfluent aphasias.A notable finding was that individual patients could be affected by cooccurring movement and other neurodegenerative disorders, each of which could be exceptionally rare (ie, prevalence of ∼1:1000), and therefore with the collective probability that such disorders were merely coincidental and causally unrelated being as low as ∼1-per-billion. Whereas our review of the literature revealed that ubiquitous patterns of clinical injury were frequently associated with magnetic resonance imaging (MRI) findings suggestive of a widespread vasculopathy, our patients did not have such neuroimaging findings. Instead, our patients could have syndromes which phenotypically resembled paraneoplastic and other inflammatory disorders which are known to be associated with antineuronal antibodies. We similarly identified immune-mediated and inflammatory markers of injury in a psoriatic arthritis patient who developed an amyotrophic lateral sclerosis (ALS)-plus syndrome after tumor necrosis factor (TNF)-inhibitor therapy.We have described a diverse spectrum of movement and other neurodegenerative disorders in our rheumatic disease patients. The widespread pattern of clinical injury, the propensity of our patients to present with co-occurring movement disorders, and the lack of MRI neuroimaging findings suggestive of a vasculopathy collectively suggest unique patterns of immune-mediated injury.
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Affiliation(s)
- Rikitha Menezes
- From the Division of Rheumatology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (RM); Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (AP); Division of Neuroradiology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (II); and Division of Rheumatology and Department of Neurology, The Johns Hopkins University School of Medicine, Baltimore, Maryland (JB)
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Findlay AR, Goyal NA, Mozaffar T. An overview of polymyositis and dermatomyositis. Muscle Nerve 2015; 51:638-56. [PMID: 25641317 DOI: 10.1002/mus.24566] [Citation(s) in RCA: 151] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/02/2015] [Indexed: 12/23/2022]
Abstract
Polymyositis and dermatomyositis are inflammatory myopathies that differ in their clinical features, histopathology, response to treatment, and prognosis. Although their clinical pictures differ, they both present with symmetrical, proximal muscle weakness. Treatment relies mainly upon empirical use of corticosteroids and immunosuppressive agents. A deeper understanding of the molecular pathways that drive pathogenesis, careful phenotyping, and accurate disease classification will aid clinical research and development of more efficacious treatments. In this review we address the current knowledge of the epidemiology, clinical characteristics, diagnostic evaluation, classification, pathogenesis, treatment, and prognosis of polymyositis and dermatomyositis.
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Affiliation(s)
- Andrew R Findlay
- Department of Neurology, University of California, Irvine UC Irvine, MDA ALS and Neuromuscular Center, 200 South Manchester Avenue, Suite 110, Orange, California, 92868, USA
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Stern JNH, Yaari G, Vander Heiden JA, Church G, Donahue WF, Hintzen RQ, Huttner AJ, Laman JD, Nagra RM, Nylander A, Pitt D, Ramanan S, Siddiqui BA, Vigneault F, Kleinstein SH, Hafler DA, O'Connor KC. B cells populating the multiple sclerosis brain mature in the draining cervical lymph nodes. Sci Transl Med 2015; 6:248ra107. [PMID: 25100741 DOI: 10.1126/scitranslmed.3008879] [Citation(s) in RCA: 327] [Impact Index Per Article: 32.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by autoimmune-mediated demyelination and neurodegeneration. The CNS of patients with MS harbors expanded clones of antigen-experienced B cells that reside in distinct compartments including the meninges, cerebrospinal fluid (CSF), and parenchyma. It is not understood whether this immune infiltrate initiates its development in the CNS or in peripheral tissues. B cells in the CSF can exchange with those in peripheral blood, implying that CNS B cells may have access to lymphoid tissue that may be the specific compartment(s) in which CNS-resident B cells encounter antigen and experience affinity maturation. Paired tissues were used to determine whether the B cells that populate the CNS mature in the draining cervical lymph nodes (CLNs). High-throughput sequencing of the antibody repertoire demonstrated that clonally expanded B cells were present in both compartments. Founding members of clones were more often found in the draining CLNs. More mature clonal members derived from these founders were observed in the draining CLNs and also in the CNS, including lesions. These data provide new evidence that B cells traffic freely across the tissue barrier, with the majority of B cell maturation occurring outside of the CNS in the secondary lymphoid tissue. Our study may aid in further defining the mechanisms of immunomodulatory therapies that either deplete circulating B cells or affect the intrathecal B cell compartment by inhibiting lymphocyte transmigration into the CNS.
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Affiliation(s)
- Joel N H Stern
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511, USA
| | - Gur Yaari
- Department of Pathology, Yale School of Medicine, New Haven, CT 06511, USA. Bioengineering Program, Faculty of Engineering, Bar-Ilan University, Ramat Gan 52900, Israel
| | - Jason A Vander Heiden
- Interdepartmental Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT 06511, USA
| | - George Church
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA
| | | | - Rogier Q Hintzen
- Department of Neurology, Erasmus MC, University Medical Center Rotterdam, and MS Centrum ErasMS, 3000 CA Rotterdam, the Netherlands
| | - Anita J Huttner
- Department of Pathology, Yale School of Medicine, New Haven, CT 06511, USA
| | - Jon D Laman
- Department of Immunology, Erasmus MC, University Medical Center Rotterdam, and MS Centrum ErasMS, 3000 CA Rotterdam, the Netherlands
| | - Rashed M Nagra
- Neurology Research, West Los Angeles VA Medical Center, Los Angeles, CA 90073, USA
| | - Alyssa Nylander
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511, USA
| | - David Pitt
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511, USA
| | - Sriram Ramanan
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511, USA
| | - Bilal A Siddiqui
- Department of Neurology, Yale School of Medicine, New Haven, CT 06511, USA
| | - Francois Vigneault
- Department of Genetics, Harvard Medical School, Boston, MA 02115, USA. AbVitro Incorporated, Boston, MA 02210, USA
| | - Steven H Kleinstein
- Department of Pathology, Yale School of Medicine, New Haven, CT 06511, USA. Interdepartmental Program in Computational Biology and Bioinformatics, Yale University, New Haven, CT 06511, USA.
| | - David A Hafler
- 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.
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Kleffel S, Vergani A, Tezza S, Ben Nasr M, Niewczas MA, Wong S, Bassi R, D'Addio F, Schatton T, Abdi R, Atkinson M, Sayegh MH, Wen L, Wasserfall CH, O'Connor KC, Fiorina P. Interleukin-10+ regulatory B cells arise within antigen-experienced CD40+ B cells to maintain tolerance to islet autoantigens. Diabetes 2015; 64:158-71. [PMID: 25187361 PMCID: PMC4274804 DOI: 10.2337/db13-1639] [Citation(s) in RCA: 82] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Accepted: 07/31/2014] [Indexed: 12/17/2022]
Abstract
Impaired regulatory B cell (Breg) responses are associated with several autoimmune diseases in humans; however, the role of Bregs in type 1 diabetes (T1D) remains unclear. We hypothesized that naturally occurring, interleukin-10 (IL-10)-producing Bregs maintain tolerance to islet autoantigens, and that hyperglycemic nonobese diabetic (NOD) mice and T1D patients lack these potent negative regulators. IgVH transcriptome analysis revealed that islet-infiltrating B cells in long-term normoglycemic (Lnglc) NOD, which are naturally protected from diabetes, are more antigen-experienced and possess more diverse B-cell receptor repertoires compared to those of hyperglycemic (Hglc) mice. Importantly, increased levels of Breg-promoting CD40(+) B cells and IL-10-producing B cells were found within islets of Lnglc compared to Hglc NOD. Likewise, healthy individuals showed increased frequencies of both CD40(+) and IL-10(+) B cells compared to T1D patients. Rituximab-mediated B-cell depletion followed by adoptive transfer of B cells from Hglc mice induced hyperglycemia in Lnglc human CD20 transgenic NOD mouse models. Importantly, both murine and human IL-10(+) B cells significantly abrogated T-cell-mediated responses to self- or islet-specific peptides ex vivo. Together, our data suggest that antigen-matured Bregs may maintain tolerance to islet autoantigens by selectively suppressing autoreactive T-cell responses, and that Hglc mice and individuals with T1D lack this population of Bregs.
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Affiliation(s)
- Sonja Kleffel
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Andrea Vergani
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA Transplant Medicine, Istituto di Ricovero e Cura a Carattere Scientifico Ospedale San Raffaele, Milano, Italy
| | - Sara Tezza
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Moufida Ben Nasr
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Monika A Niewczas
- Section on Genetics and Epidemiology, Research Division, Joslin Diabetes Center and Department of Medicine, Harvard Medical School, Boston, MA
| | - Susan Wong
- Institute of Molecular and Experimental Medicine, Cardiff University School of Medicine, Cardiff, U.K
| | - Roberto Bassi
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Francesca D'Addio
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA Transplant Medicine, Istituto di Ricovero e Cura a Carattere Scientifico Ospedale San Raffaele, Milano, Italy
| | - Tobias Schatton
- Harvard Skin Disease Research Center, Department of Dermatology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA Transplant Research Program, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Reza Abdi
- Nephrology Division, Brigham and Women's Hospital, Harvard Medical School, Boston, MA
| | - Mark Atkinson
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL
| | - Mohamed H Sayegh
- Transplant Research Program, Boston Children's Hospital, Harvard Medical School, Boston, MA
| | - Li Wen
- Department of Immunology, Yale School of Medicine, New Haven, CT
| | - Clive H Wasserfall
- Department of Pathology, Immunology and Laboratory Medicine, University of Florida, Gainesville, FL
| | | | - Paolo Fiorina
- Nephrology Division, Boston Children's Hospital, Harvard Medical School, Boston, MA Transplant Medicine, Istituto di Ricovero e Cura a Carattere Scientifico Ospedale San Raffaele, Milano, Italy
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Kryštůfková O, Barbasso Helmers S, Venalis P, Malmström V, Lindroos E, Vencovský J, Lundberg IE. Expression of BAFF receptors in muscle tissue of myositis patients with anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies. Arthritis Res Ther 2014; 16:454. [PMID: 25301447 PMCID: PMC4234835 DOI: 10.1186/s13075-014-0454-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2014] [Accepted: 09/10/2014] [Indexed: 01/18/2023] Open
Abstract
INTRODUCTION Anti-Jo-1 and anti-Ro52 autoantibodies are common in patients with myositis, but the mechanisms behind their production are not known. Survival of autoantibody-producing cells is dependent on B-cell-activating factor of the tumour necrosis factor family (BAFF). BAFF levels are elevated in serum of anti-Jo-1-positive myositis patients and are influenced by type-I interferon (IFN). IFN-producing cells and BAFF mRNA expression are present in myositis muscle. We investigated expression of the receptors for BAFF in muscle tissue in relation to anti-Jo-1 and anti-Ro52/anti-Ro60 autoantibodies and type-I IFN markers. METHODS Muscle biopsies from 23 patients with myositis selected based on autoantibody profile and 7 healthy controls were investigated for expression of BAFF receptor (BAFF-R), B-cell maturation antigen (BCMA) and transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI). Nineteen samples were assessed for plasma (CD138) and B-cell (CD19) markers. The numbers of positive cells per area were compared with the expression of plasmacytoid dendritic cell (pDC) marker blood dendritic cell antigen-2 (BDCA-2) and IFNα/β-inducible myxovirus resistance-1 protein (MX-1). RESULTS BAFF-R, BCMA and TACI were expressed in five, seven and seven patients, respectively, and more frequently in anti-Jo-1-positive and/or anti-Ro52/anti-Ro60-positive patients compared to controls and to patients without these autoantibodies (P = BAFF-R: 0.007, BCMA: 0.03 and TACI: 0.07). A local association of receptors with B and plasma cells was confirmed by confocal microscopy. The numbers of CD138-positive and BCMA-positive cells were correlated (r = 0.79; P = 0.001). Expression of BDCA-2 correlated with numbers of CD138-positive cells and marginally with BCMA-positive cells (r = 0.54 and 0.42, respectively; P = 0.04 and 0.06, respectively). There was a borderline correlation between the numbers of positively stained TACI cells and MX-1 areas (r = 0.38, P = 0.08). CONCLUSIONS The expression pattern of receptors for BAFF on B and plasma cells in muscle suggests a local role for BAFF in autoantibody production in muscle tissues of patients with myositis who have anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies. BAFF production could be influenced by type-I IFN produced by pDCs. Thus, B-cell-related molecular pathways may participate in the pathogenesis of myositis in this subset of patients.
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Greenberg SA. Cytoplasmic 5′-nucleotidase autoantibodies in inclusion body myositis: Isotypes and diagnostic utility. Muscle Nerve 2014; 50:488-92. [DOI: 10.1002/mus.24199] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Revised: 01/30/2014] [Accepted: 02/04/2014] [Indexed: 11/12/2022]
Affiliation(s)
- Steven A. Greenberg
- Department of Neurology, Brigham and Women's Hospital and Children's Hospital Informatics Program; Harvard Medical School and Harvard-MIT Division of Health Sciences and Technology; Boston Massachusetts USA
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Berrih-Aknin S. Myasthenia Gravis: paradox versus paradigm in autoimmunity. J Autoimmun 2014; 52:1-28. [PMID: 24934596 DOI: 10.1016/j.jaut.2014.05.001] [Citation(s) in RCA: 89] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2014] [Accepted: 05/07/2014] [Indexed: 12/12/2022]
Abstract
Myasthenia Gravis (MG) is a paradigm of organ-specific autoimmune disease (AID). It is mediated by antibodies that target the neuromuscular junction. The purpose of this review is to place MG in the general context of autoimmunity, to summarize the common mechanisms between MG and other AIDs, and to describe the specific mechanisms of MG. We have chosen the most common organ-specific AIDs to compare with MG: type 1 diabetes mellitus (T1DM), autoimmune thyroid diseases (AITD), multiple sclerosis (MS), some systemic AIDs (systemic lupus erythematous (SLE), rheumatoid arthritis (RA), Sjogren's syndrome (SS)), as well as inflammatory diseases of the gut and liver (celiac disease (CeD), Crohn's disease (CD), and primary biliary cirrhosis (PBC)). Several features are similar between all AIDs, suggesting that common pathogenic mechanisms lead to their development. In this review, we address the predisposing factors (genetic, epigenetic, hormones, vitamin D, microbiota), the triggering components (infections, drugs) and their interactions with the immune system [1,2]. The dysregulation of the immune system is detailed and includes the role of B cells, Treg cells, Th17 and cytokines. We particularly focused on the role of TNF-α and interferon type I whose role in MG is very analogous to that in several other AIDS. The implication of AIRE, a key factor in central tolerance is also discussed. Finally, if MG is a prototype of AIDS, it has a clear specificity compared to the other AIDS, by the fact that the target organ, the muscle, is not the site of immune infiltration and B cell expansion, but exclusively that of antibody-mediated pathogenic mechanisms. By contrast, the thymus in the early onset subtype frequently undergoes tissue remodeling, resulting in the development of ectopic germinal centers surrounded by high endothelial venules (HEV), as observed in the target organs of many other AIDs.
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Affiliation(s)
- Sonia Berrih-Aknin
- Sorbonne Universités, UPMC Univ Paris 06, Myology Research Center UM76, F-75013 Paris, France; INSERM U974, F-75013 Paris, France; CNRS FRE 3617, F-75013 Paris, France; Institute of Myology, F-75013 Paris, France.
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