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Li S, Zhang Y, Liu G, Song N, Ruan Z, Guo R, Tang Y, Cao X, Huang X, Gao T, Hao S, Wang Q, Chang T. Exploring the Roles of m6A-Modified circRNAs in Myasthenia Gravis Based on Multi-Omics Analysis. Mol Neurobiol 2024:10.1007/s12035-024-04352-9. [PMID: 39017976 DOI: 10.1007/s12035-024-04352-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Accepted: 07/03/2024] [Indexed: 07/18/2024]
Abstract
Myasthenia gravis (MG) is an autoimmune disease mediated by autoantibodies. The important roles of circRNAs modified by m6A methylation have been reported in the pathogenesis of other autoimmune diseases, but remain unclear in MG. To address this point, we collected peripheral blood mononuclear cells from six MG patients and six healthy controls and performed m6A‑circRNA epitranscriptomic microarray and RNA sequencing. Differentially m6A-modified circRNAs and differentially expressed genes (DEGs) were analyzed. A network was constructed containing 17 circRNAs, 30 miRNAs, and 34 DEGs. The GSE85452 dataset was downloaded. DEGs that were differentially expressed in the GSE85452 dataset were selected as seed genes. Finally, four candidate m6A-modified circRNAs (hsa_circ_0084735, hsa_circ_0018652, hsa_circ_0025731, and hsa_circ_0030997) were identified through a random walk with restart. We found that they had different degree correlations with different immune cells. The results of MeRIP-qPCR showed that the m6A methylated levels of hsa_circ_0084735 and hsa_circ_0025731 were downregulated in MG patients, while the other two circRNAs were not significantly different between MG and control group. For the first time, we explored the pathogenesis of MG at the epigenetic transcriptome level. Our results will open new perspectives for MG research and identify potential biomarkers and therapeutic targets for MG.
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Affiliation(s)
- Shuang Li
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Yu Zhang
- Department of Neurosurgery, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Geyu Liu
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
- The Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Na Song
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Zhe Ruan
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Rongjing Guo
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Yonglan Tang
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Xiangqi Cao
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Xiaoxi Huang
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Ting Gao
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Sijia Hao
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Qingqing Wang
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Ting Chang
- Department of Neurology, Tangdu Hospital, the Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
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Dong J, Duan RS, Zhang P. Causal relationship between the immune phenotype of monocytes and myasthenia gravis: A Mendelian randomization study. Heliyon 2024; 10:e26741. [PMID: 38449651 PMCID: PMC10915380 DOI: 10.1016/j.heliyon.2024.e26741] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Revised: 01/30/2024] [Accepted: 02/19/2024] [Indexed: 03/08/2024] Open
Abstract
Background Monocytes play an essential role in developing autoimmune diseases; however, their association with myasthenia gravis (MG) development is unclear. Methods We performed a two-sample Mendelian randomization analysis to assess the causal relationship between monocyte-associated traits and MG, reviewing summary statistics of genome-wide association studies (GWAS). Results Using the inverse variance weighted method, the following were found to be causally associated with MG: HLA-DR on monocytes (OR, 1.363; 95% CI, 1.158-1.605; P = 2E-04), HLA-DR on CD14+ monocytes (OR, 1.324; 95% CI, 1.183-1.482; P = 1.08E-06), HLA-DR on CD14+CD16- monocytes (OR, 1.313; 95% CI, 1.177-1.465; P = 1.07E-06), CD40 on monocytes (OR, 1.135; 95% CI, 1.012-1.272; P < 0.05), CD40 on CD14+CD16- monocytes (OR, 1.142; 95% CI, 1.015-1.285; P < 0.05), CD40 on CD14+CD16+ monocytes (OR, 1.142; 95% CI, 1.021-1.278; P < 0.05), CD64 on CD14+CD16+ monocytes (OR, 1.286; 95% CI, 1.019-1.623; P < 0.05). Conclusions The present study suggests a causal relationship between the upregulation of CD40, HLA-DR, and CD64 on monocytes and the development of MG. Altered monocyte function may potentially be a risk factor for MG and a therapeutic target.
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Affiliation(s)
- Jing Dong
- Department of Neurology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, Shandong Province, China
| | - Rui-sheng Duan
- Department of Neurology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, Shandong Province, China
- Shandong Institute of Neuroimmunology, Jinan, Shandong Province, China
- Shandong Provincial Medicine and Health Key Laboratory of Neuroimmunology, Shandong Province, China
- Shandong Key Laboratory of Rheumatic Disease and Translational Medicine, Jinan, Shandong Province, China
| | - Peng Zhang
- Department of Neurology, The First Affiliated Hospital of Shandong First Medical University & Shandong Provincial Qianfoshan Hospital, Jinan, Shandong Province, China
- Shandong Institute of Neuroimmunology, Jinan, Shandong Province, China
- Shandong Provincial Medicine and Health Key Laboratory of Neuroimmunology, Shandong Province, China
- Shandong Key Laboratory of Rheumatic Disease and Translational Medicine, Jinan, Shandong Province, China
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Zhong H, Huan X, Zhao R, Su M, Yan C, Song J, Xi J, Zhao C, Luo F, Luo S. Peripheral immune landscape for hypercytokinemia in myasthenic crisis utilizing single-cell transcriptomics. J Transl Med 2023; 21:564. [PMID: 37620910 PMCID: PMC10464341 DOI: 10.1186/s12967-023-04421-y] [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: 02/16/2023] [Accepted: 08/07/2023] [Indexed: 08/26/2023] Open
Abstract
BACKGROUND Myasthenia gravis (MG) is the most prevalent autoimmune disorder affecting the neuromuscular junction. A rapid deterioration in respiratory muscle can lead to a myasthenic crisis (MC), which represents a life-threatening condition with high mortality in MG. Multiple CD4+ T subsets and hypercytokinemia have been identified in the peripheral pro-inflammatory milieu during the crisis. However, the pathogenesis is complicated due to the many types of cells involved, leaving the underlying mechanism largely unexplored. METHODS We conducted single-cell transcriptomic and immune repertoire sequencing on 33,577 peripheral blood mononuclear cells (PBMCs) from two acetylcholine receptor antibody-positive (AChR +) MG patients during MC and again three months post-MC. We followed the Scanpy workflow for quality control, dimension reduction, and clustering of the single-cell data. Subsequently, we annotated high-resolution cell types utilizing transfer-learning models derived from publicly available single-cell immune datasets. RNA velocity calculations from unspliced and spliced mRNAs were applied to infer cellular state progression. We analyzed cell communication and MG-relevant cytokines and chemokines to identify potential inflammation initiators. RESULTS We identified a unique subset of monocytes, termed monocytes 3 (FCGR3B+ monocytes), which exhibited significant differential expression of pro-inflammatory signaling pathways during and after the crisis. In line with the activated innate immune state indicated by MC, a high neutrophil-lymphocyte ratio (NLR) was confirmed in an additional 22 AChR + MC patients in subsequent hemogram analysis and was associated with MG-relevant clinical scores. Furthermore, oligoclonal expansions were identified in age-associated B cells exhibiting high autoimmune activity, and in CD4+ and CD8+ T cells demonstrating persistent T exhaustion. CONCLUSIONS In summary, our integrated analysis of single-cell transcriptomics and TCR/BCR sequencing has underscored the role of innate immune activation which is associated with hypercytokinemia in MC. The identification of a specific monocyte cluster that dominates the peripheral immune profile may provide some hints into the etiology and pathology of MC. However, future functional studies are required to explore causality.
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Affiliation(s)
- Huahua Zhong
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Xiao Huan
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Rui Zhao
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Manqiqige Su
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Chong Yan
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Jie Song
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Jianying Xi
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Chongbo Zhao
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China
| | - Feifei Luo
- Department of Digestive Diseases, Huashan Hospital, Fudan University, Shanghai, 200040, China.
| | - Sushan Luo
- Huashan Rare Disease Center and Department of Neurology, Huashan Hospital, Shanghai Medical College, National Center for Neurological Disorders, Fudan University, Shanghai, 200040, China.
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Zhang D, Luo L, Lu F, Li B, Lai X. Transcriptional landscape of myasthenia gravis revealed by weighted gene coexpression network analysis. Front Genet 2023; 14:1106359. [PMID: 37051601 PMCID: PMC10083720 DOI: 10.3389/fgene.2023.1106359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 03/14/2023] [Indexed: 03/29/2023] Open
Abstract
Background: As one of the most common autoimmune diseases, myasthenia gravis (MG) severely affects the quality of life of patients. Therefore, exploring the role of dysregulated genes between MG and healthy controls in the diagnosis of MG is beneficial to reveal new and promising diagnostic biomarkers and clinical therapeutic targets.Methods: The GSE85452 dataset was downloaded from the Gene Expression Omnibus (GEO) database and differential gene expression analysis was performed on MG and healthy control samples to identify differentially expressed genes (DEGs). The functions and pathways involved in DEGs were also explored by functional enrichment analysis. Significantly associated modular genes were identified by weighted gene co-expression network analysis (WGCNA), and MG dysregulated gene co-expression modular-based diagnostic models were constructed by gene set variance analysis (GSVA) and least absolute shrinkage and selection operator (LASSO). In addition, the effect of model genes on tumor immune infiltrating cells was assessed by CIBERSORT. Finally, the upstream regulators of MG dysregulated gene co-expression module were obtained by Pivot analysis.Results: The green module with high diagnostic performance was identified by GSVA and WGCNA. The LASSO model obtained NAPB, C5orf25 and ERICH1 genes had excellent diagnostic performance for MG. Immune cell infiltration results showed a significant negative correlation between green module scores and infiltration abundance of Macrophages M2 cells.Conclusion: In this study, a diagnostic model based on the co-expression module of MG dysregulated genes was constructed, which has good diagnostic performance and contributes to the diagnosis of MG.
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Li S, Liu H, Ruan Z, Guo R, Sun C, Tang Y, Huang X, Gao T, Hao S, Li H, Song N, Su Y, Ning F, Li Z, Chang T. Landscape analysis of m6A modification regulators related biological functions and immune characteristics in myasthenia gravis. J Transl Med 2023; 21:166. [PMID: 36864526 PMCID: PMC9983271 DOI: 10.1186/s12967-023-03947-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Accepted: 02/01/2023] [Indexed: 03/04/2023] Open
Abstract
BACKGROUND N6-methyladenosine (m6A) modification has been recognized to play fundamental roles in the development of autoimmune diseases. However, the implication of m6A modification in myasthenia gravis (MG) remains largely unknown. Thus, we aimed to systematically explore the potential functions and related immune characteristics of m6A regulators in MG. METHODS The GSE85452 dataset with MG and healthy samples was downloaded from Gene Expression Omnibus (GEO) database. m6A modification regulators were manually curated. The targets of m6A regulators were obtained from m6A2Target database. The differential expressed m6A regulators in GSE85452 dataset were identified by "limma" package and were validated by RT-PCR. Function enrichment analysis of dysregulated m6A regulators was performed using "clusterProfiler" package. Correlation analysis was applied for analyzing the relationships between m6A regulators and immune characteristics. Unsupervised clustering analysis was used to identify distinct m6A modification subtypes. The differences between subtypes were analyzed, including the expression level of all genes and the enrichment degree of immune characteristics. Weighted gene co-expression network analysis (WGCNA) was conducted to obtain modules associated with m6A modification subtypes. RESULTS We found that CBLL1, RBM15 and YTHDF1 were upregulated in MG samples of GSE85452 dataset, and the results were verified by RT-PCR in blood samples from19 MG patients and 19 controls. The targeted genes common modified by CBLL1, RBM15, and YTHDF1 were mainly enriched in histone modification and Wnt signaling pathway. Correlation analysis showed that three dysregulated m6A regulators were closely associated with immune characteristics. Among them, RBM15 possessed the strongest correlation with immune characteristics, including CD56dim natural killer cell (r = 0.77, P = 0.0023), T follicular helper cell (r = - 0.86, P = 0.0002), Interferon Receptor (r = 0.78, P = 0.0017), and HLA-DOA (r = 0.64, P = 0.0200). Further two distinct m6A modification patterns mediated by three dysregulated m6A regulators was identified. Bioinformatics analysis found that there were 3029 differentially expressed genes and different immune characteristics between two m6A modification patterns. Finally, WGCNA analysis obtained a total of 12 modules and yellow module was the most positively correlated to subtype-2. CONCLUSION Our findings suggested that m6A RNA modification had an important effect on immunity molecular mechanism of MG and provided a new perspective into understanding the pathogenesis of MG.
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Affiliation(s)
- Shuang Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Hui Liu
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.,Xi'an Medical University, Xi'an, 710021, Shaanxi, China
| | - Zhe Ruan
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Rongjing Guo
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Chao Sun
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Yonglan Tang
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Xiaoxi Huang
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Ting Gao
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Sijia Hao
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Huanhuan Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Na Song
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Yue Su
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Fan Ning
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Zhuyi Li
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China
| | - Ting Chang
- Department of Neurology, Tangdu Hospital, The Fourth Military Medical University, Xi'an, 710038, Shaanxi, China.
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Verdier J, Fayet OM, Hemery E, Truffault F, Pinzón N, Demeret S, Behin A, Fadel E, Guihaire J, Corneau A, Blanc C, Berrih-Aknin S, Le Panse R. Single-cell mass cytometry on peripheral cells in Myasthenia Gravis identifies dysregulation of innate immune cells. Front Immunol 2023; 14:1083218. [PMID: 36793723 PMCID: PMC9922723 DOI: 10.3389/fimmu.2023.1083218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Accepted: 01/04/2023] [Indexed: 01/31/2023] Open
Abstract
Myasthenia Gravis (MG) is a neurological autoimmune disease characterized by disabling muscle weaknesses due to anti-acetylcholine receptor (AChR) autoantibodies. To gain insight into immune dysregulation underlying early-onset AChR+ MG, we performed an in-depth analysis of peripheral mononuclear blood cells (PBMCs) using mass cytometry. PBMCs from 24 AChR+ MG patients without thymoma and 16 controls were stained with a panel of 37 antibodies. Using both unsupervised and supervised approaches, we observed a decrease in monocytes, for all subpopulations: classical, intermediate, and non-classical monocytes. In contrast, an increase in innate lymphoid cells 2 (ILC2s) and CD27- γδ T cells was observed. We further investigated the dysregulations affecting monocytes and γδ T cells in MG. We analyzed CD27- γδ T cells in PBMCs and thymic cells from AChR+ MG patients. We detected the increase in CD27- γδ T cells in thymic cells of MG patients suggesting that the inflammatory thymic environment might affect γδ T cell differentiation. To better understand changes that might affect monocytes, we analyzed RNA sequencing data from CD14+ PBMCs and showed a global decrease activity of monocytes in MG patients. Next, by flow cytometry, we especially confirmed the decrease affecting non-classical monocytes. In MG, as for other B-cell mediated autoimmune diseases, dysregulations are well known for adaptive immune cells, such as B and T cells. Here, using single-cell mass cytometry, we unraveled unexpected dysregulations for innate immune cells. If these cells are known to be crucial for host defense, our results demonstrated that they could also be involved in autoimmunity.
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Affiliation(s)
- Julien Verdier
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Odessa-Maud Fayet
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Edouard Hemery
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Frédérique Truffault
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Natalia Pinzón
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Sophie Demeret
- APHP, Assistance Publique - Hopitaux de Paris, Paris, France
| | - Anthony Behin
- AP-HP, Referral Center for Neuromuscular Disorders, Institute of Myology, Pitié-Salpêtrière Hospital, Paris, France
| | - Elie Fadel
- Marie Lannelongue Hospital, Paris-Sud University, Le Plessis-Robinson, France
| | - Julien Guihaire
- Marie Lannelongue Hospital, Paris-Sud University, Le Plessis-Robinson, France
| | - Aurélien Corneau
- Plateforme de Cytométrie de la Pitié-Salpétrière (CyPS), UMS037-PASS, Sorbonne Université-Faculté de Médecine, Paris, France
| | - Catherine Blanc
- Plateforme de Cytométrie de la Pitié-Salpétrière (CyPS), UMS037-PASS, Sorbonne Université-Faculté de Médecine, Paris, France
| | - Sonia Berrih-Aknin
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
| | - Rozen Le Panse
- Sorbonne University, INSERM, Institute of Myology, Center of Research in Myology, Paris, France
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Lancaster EE, Vladimirov VI, Riley BP, Landry JW, Roberson-Nay R, York TP. LARGE-SCALE INTEGRATION OF DNA METHYLATION AND GENE EXPRESSION ARRAY PLATFORMS IDENTIFIES BOTH cis AND trans RELATIONSHIPS. Epigenetics 2022; 17:1753-1773. [PMID: 35608069 PMCID: PMC9621057 DOI: 10.1080/15592294.2022.2079293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Although epigenome-wide association studies (EWAS) have been successful in identifying DNA methylation (DNAm) patterns associated with disease states, any further characterization of etiologic mechanisms underlying disease remains elusive. This knowledge gap does not originate from a lack of DNAm–trait associations, but rather stems from study design issues that affect the interpretability of EWAS results. Despite known limitations in predicting the function of a particular CpG site, most EWAS maintain the broad assumption that altered DNAm results in a concomitant change of transcription at the most proximal gene. This study integrated DNAm and gene expression (GE) measurements in two cohorts, the Adolescent and Young Adult Twin Study (AYATS) and the Pregnancy, Race, Environment, Genes (PREG) study, to improve the understanding of epigenomic regulatory mechanisms. CpG sites associated with GE in cis were enriched in areas of transcription factor binding and areas of intermediate-to-low CpG density. CpG sites associated with trans GE were also enriched in areas of known regulatory significance, including enhancer regions. These results highlight issues with restricting DNAm-transcript annotations to small genomic intervals and question the validity of assuming a cis DNAm–GE pathway. Based on these findings, the interpretation of EWAS results is limited in studies without multi-omic support and further research should identify genomic regions in which GE-associated DNAm is overrepresented. An in-depth characterization of GE-associated CpG sites could improve predictions of the downstream functional impact of altered DNAm and inform best practices for interpreting DNAm–trait associations generated by EWAS.
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Affiliation(s)
- Eva E Lancaster
- Department of Psychiatry, Virginia Commonwealth University, Richmond, VA 23220
| | | | - Brien P Riley
- Department of Psychiatry, Virginia Commonwealth University, Richmond, VA 23220.,Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA 23220
| | - Joseph W Landry
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA 23220
| | - Roxann Roberson-Nay
- Department of Psychiatry, Virginia Commonwealth University, Richmond, VA 23220.,Department of Psychology, Virginia Commonwealth University, Richmond, VA 23220
| | - Timothy P York
- Department of Human and Molecular Genetics, Virginia Commonwealth University, Richmond, VA 23220.,Department of Obstetrics and Gynecology, Virginia Commonwealth University, Richmond, VA 23220
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Shi X, Wang Q, Sun C, Guo Q, Song T. Study on the role of methylation in nonsyndromic cleft lip with or without cleft palate using a monozygotic twin model. Int J Pediatr Otorhinolaryngol 2021; 143:110659. [PMID: 33667834 DOI: 10.1016/j.ijporl.2021.110659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/08/2020] [Accepted: 02/19/2021] [Indexed: 11/28/2022]
Abstract
OBJECTIVE The research on the etiology of nonsyndromic cleft lip with or without cleft palate(NSCL/P) is challenging, and DNA methylation has an impact on the formation of cleft lip and palate. SUBJECTS In this study, one of a pair of monozygotic twins (T1) had nonsyndromic cleft lip (NSCL), and one of a pair of monozygotic twins (T2) had nonsyndromic cleft lip and palate (NSCLP). We determined the methylation profiles of more than 850,000 CpGs in the DNA of the blood samples from the two pairs of monozygotic twins. RESULT Methylation data indicated that 1184 differentially methylated CpG sites were found in the T1 group (651 hypermethylated and 533 hypomethylated) and 8099 differentially methylated CpG sites in the T2 group (1713 hypermethylated and 6386 hypomethylated) compared with the healthy twin.The common difference was 107 methylation sites.GO enrichment analysis showed that regulation of smooth muscle cell migration and actin cytoskeleton reorganization were the most prominent classes.KEGG pathway enrichment analysis showed that the TGF-β signaling pathway, Notch signaling pathway and Wnt signaling pathway are relevant to the formation of NSCL/P.Two selected genes (NTN1 and PLEKHA7) are involved in the formation of NSCL/P. CONCLUSION These findings provide some support for the hypothesis that abnormal DNA methylation may influence the formation of clefts.
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Affiliation(s)
- Xuheng Shi
- Department of Stomatology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China
| | - Qi Wang
- Department of Stomatology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China
| | - Changsheng Sun
- Department of Stomatology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China
| | - Qiang Guo
- Department of Ophthalmology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China
| | - Tao Song
- Department of Stomatology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, China.
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Schmidt M, Maié T, Dahl E, Costa IG, Wagner W. Deconvolution of cellular subsets in human tissue based on targeted DNA methylation analysis at individual CpG sites. BMC Biol 2020; 18:178. [PMID: 33234153 PMCID: PMC7687708 DOI: 10.1186/s12915-020-00910-4] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 10/28/2020] [Indexed: 12/12/2022] Open
Abstract
Background The complex composition of different cell types within a tissue can be estimated by deconvolution of bulk gene expression profiles or with various single-cell sequencing approaches. Alternatively, DNA methylation (DNAm) profiles have been used to establish an atlas for multiple human tissues and cell types. DNAm is particularly suitable for deconvolution of cell types because each CG dinucleotide (CpG site) has only two states per DNA strand—methylated or non-methylated—and these epigenetic modifications are very consistent during cellular differentiation. So far, deconvolution of DNAm profiles implies complex signatures of many CpGs that are often measured by genome-wide analysis with Illumina BeadChip microarrays. In this study, we investigated if the characterization of cell types in tissue is also feasible with individual cell type-specific CpG sites, which can be addressed by targeted analysis, such as pyrosequencing. Results We compiled and curated 579 Illumina 450k BeadChip DNAm profiles of 14 different non-malignant human cell types. A training and validation strategy was applied to identify and test for cell type-specific CpGs. We initially focused on estimating the relative amount of fibroblasts using two CpGs that were either hypermethylated or hypomethylated in fibroblasts. The combination of these two DNAm levels into a “FibroScore” correlated with the state of fibrosis and was associated with overall survival in various types of cancer. Furthermore, we identified hypomethylated CpGs for leukocytes, endothelial cells, epithelial cells, hepatocytes, glia, neurons, fibroblasts, and induced pluripotent stem cells. The accuracy of this eight CpG signature was tested in additional BeadChip datasets of defined cell mixtures and the results were comparable to previously published signatures based on several thousand CpGs. Finally, we established and validated pyrosequencing assays for the relevant CpGs that can be utilized for classification and deconvolution of cell types. Conclusion This proof of concept study demonstrates that DNAm analysis at individual CpGs reflects the cellular composition of cellular mixtures and different tissues. Targeted analysis of these genomic regions facilitates robust methods for application in basic research and clinical settings.
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Affiliation(s)
- Marco Schmidt
- Helmholtz-Institute for Biomedical Engineering, Stem Cell Biology and Cellular Engineering, RWTH Aachen University Medical School, 52074, Aachen, Germany.,Institute for Biomedical Engineering - Cell Biology, University Hospital of RWTH Aachen, 52074, Aachen, Germany
| | - Tiago Maié
- Institute for Computational Genomics, Joint Research Center for Computational Biomedicine, RWTH Aachen University Medical School, 52074, Aachen, Germany
| | - Edgar Dahl
- RWTH centralized Biomaterial Bank (RWTH cBMB), Medical Faculty, RWTH Aachen University, Aachen, Germany
| | - Ivan G Costa
- Institute for Computational Genomics, Joint Research Center for Computational Biomedicine, RWTH Aachen University Medical School, 52074, Aachen, Germany
| | - Wolfgang Wagner
- Helmholtz-Institute for Biomedical Engineering, Stem Cell Biology and Cellular Engineering, RWTH Aachen University Medical School, 52074, Aachen, Germany. .,Institute for Biomedical Engineering - Cell Biology, University Hospital of RWTH Aachen, 52074, Aachen, Germany.
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10
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Identifying the culprits in neurological autoimmune diseases. J Transl Autoimmun 2019; 2:100015. [PMID: 32743503 PMCID: PMC7388404 DOI: 10.1016/j.jtauto.2019.100015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/27/2019] [Accepted: 09/03/2019] [Indexed: 12/16/2022] Open
Abstract
The target organ of neurological autoimmune diseases (NADs) is the central or peripheral nervous system. Multiple sclerosis (MS) is the most common NAD, whereas Guillain-Barré syndrome (GBS), myasthenia gravis (MG), and neuromyelitis optica (NMO) are less common NADs, but the incidence of these diseases has increased exponentially in the last few years. The identification of a specific culprit in NADs is challenging since a myriad of triggering factors interplay with each other to cause an autoimmune response. Among the factors that have been associated with NADs are genetic susceptibility, epigenetic mechanisms, and environmental factors such as infection, microbiota, vitamins, etc. This review focuses on the most studied culprits as well as the mechanisms used by these to trigger NADs. Neurological autoimmune diseases are caused by a complex interaction between genes, environmental factors, and epigenetic deregulation. Infectious agents can cause an autoimmune reaction to myelin epitopes through molecular mimicry and/or bystander activation. Gut microbiota dysbiosis contributes to neurological autoimmune diseases. Smoking increases the risk of NADs through inflammatory signaling pathways, oxidative stress, and Th17 differentiation. Deficiency in vitamin D favors NAD development through direct damage to the central and peripheral nervous system.
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11
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Zhong H, Zhao C, Luo S. HLA in myasthenia gravis: From superficial correlation to underlying mechanism. Autoimmun Rev 2019; 18:102349. [DOI: 10.1016/j.autrev.2019.102349] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 03/01/2019] [Indexed: 12/26/2022]
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12
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Zyla J, Kabacik S, O'Brien G, Wakil S, Al-Harbi N, Kaprio J, Badie C, Polanska J, Alsbeih G. Combining CDKN1A gene expression and genome-wide SNPs in a twin cohort to gain insight into the heritability of individual radiosensitivity. Funct Integr Genomics 2019; 19:575-585. [PMID: 30706161 PMCID: PMC6570669 DOI: 10.1007/s10142-019-00658-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2018] [Revised: 12/12/2018] [Accepted: 01/09/2019] [Indexed: 12/15/2022]
Abstract
Individual variability in response to radiation exposure is recognised and has often been reported as important in treatment planning. Despite many efforts to identify biomarkers allowing the identification of radiation sensitive patients, it is not yet possible to distinguish them with certainty before the beginning of the radiotherapy treatment. A comprehensive analysis of genome-wide single-nucleotide polymorphisms (SNPs) and a transcriptional response to ionising radiation exposure in twins have the potential to identify such an individual. In the present work, we investigated SNP profile and CDKN1A gene expression in blood T lymphocytes from 130 healthy Caucasians with a complex level of individual kinship (unrelated, mono- or dizygotic twins). It was found that genetic variation accounts for 66% (95% CI 37-82%) of CDKN1A transcriptional response to radiation exposure. We developed a novel integrative multi-kinship strategy allowing investigating the role of genome-wide polymorphisms in transcriptomic radiation response, and it revealed that rs205543 (ETV6 gene), rs2287505 and rs1263612 (KLF7 gene) are significantly associated with CDKN1A expression level. The functional analysis revealed that rs6974232 (RPA3 gene), involved in mismatch repair (p value = 9.68e-04) as well as in RNA repair (p value = 1.4e-03) might have an important role in that process. Two missense polymorphisms with possible deleterious effect in humans were identified: rs1133833 (AKIP1 gene) and rs17362588 (CCDC141 gene). In summary, the data presented here support the validity of this novel integrative data analysis strategy to provide insights into the identification of SNPs potentially influencing radiation sensitivity. Further investigations in radiation response research at the genomic level should be therefore continued to confirm these findings.
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Affiliation(s)
- Joanna Zyla
- Data Mining Division, Faculty of Automatic Control, Electronic and Computer Science, Silesian University of Technology, Akademicka 16, 44-100, Gliwice, Poland
| | - Sylwia Kabacik
- Cellular Biology Group, Radiation Effects Department, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, OX11 0RQ, UK
| | - Grainne O'Brien
- Cancer Mechanisms and Biomarkers Group, Radiation Effects Department, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, OX11 0RQ, UK
| | - Salma Wakil
- Department of Genetics, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Kingdom of Saudi Arabia
| | - Najla Al-Harbi
- Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Kingdom of Saudi Arabia
| | - Jaakko Kaprio
- Department of Public Health and Institute for Molecular Medicine FIMM, University of Helsinki, 00140, Helsinki, Finland
| | - Christophe Badie
- Cancer Mechanisms and Biomarkers Group, Radiation Effects Department, Centre for Radiation, Chemical and Environmental Hazards, Public Health England, Chilton, Didcot, OX11 0RQ, UK
| | - Joanna Polanska
- Data Mining Division, Faculty of Automatic Control, Electronic and Computer Science, Silesian University of Technology, Akademicka 16, 44-100, Gliwice, Poland.
| | - Ghazi Alsbeih
- Radiation Biology Section, Biomedical Physics Department, King Faisal Specialist Hospital and Research Centre, Riyadh, 11211, Kingdom of Saudi Arabia
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13
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Li S, Cao Y, Li L, Zhang H, Lu X, Bo C, Kong X, Liu Z, Chen L, Liu P, Jiao Y, Wang J, Ning S, Wang L. Building the drug-GO function network to screen significant candidate drugs for myasthenia gravis. PLoS One 2019; 14:e0214857. [PMID: 30947317 PMCID: PMC6448860 DOI: 10.1371/journal.pone.0214857] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Accepted: 03/22/2019] [Indexed: 12/17/2022] Open
Abstract
Myasthenia gravis (MG) is an autoimmune disease. In recent years, considerable evidence has indicated that Gene Ontology (GO) functions, especially GO-biological processes, have important effects on the mechanisms and treatments of different diseases. However, the roles of GO functions in the pathogenesis and treatment of MG have not been well studied. This study aimed to uncover the potential important roles of risk-related GO functions and to screen significant candidate drugs related to GO functions for MG. Based on MG risk genes, 238 risk GO functions and 42 drugs were identified. Through constructing a GO function network, we discovered that positive regulation of NF-kappaB transcription factor activity (GO:0051092) may be one of the most important GO functions in the mechanism of MG. Furthermore, we built a drug-GO function network to help evaluate the latent relationship between drugs and GO functions. According to the drug-GO function network, 5 candidate drugs showing promise for treating MG were identified. Indeed, 2 out of 5 candidate drugs have been investigated to treat MG. Through functional enrichment analysis, we found that the mechanisms between 5 candidate drugs and associated GO functions may involve two vital pathways, specifically hsa05332 (graft-versus-host disease) and hsa04940 (type I diabetes mellitus). More interestingly, most of the processes in these two pathways were consistent. Our study will not only reveal a new perspective on the mechanisms and novel treatment strategies of MG, but also will provide strong support for research on GO functions.
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Affiliation(s)
- Shuang Li
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Yuze Cao
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
- Department of Neurology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China
| | - Lei Li
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Huixue Zhang
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Xiaoyu Lu
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Chunrui Bo
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Xiaotong Kong
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Zhaojun Liu
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Lixia Chen
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Peifang Liu
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Yang Jiao
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
| | - Jianjian Wang
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
- * E-mail: (LW); (SN); (JW)
| | - Shangwei Ning
- College of Bioinformatics Science and Technology, Harbin Medical University, Harbin, Heilongjiang Province, China
- * E-mail: (LW); (SN); (JW)
| | - Lihua Wang
- Department of Neurology, The Second Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang Province, China
- * E-mail: (LW); (SN); (JW)
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14
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Tanaka A, Leung PSC, Gershwin ME. Evolution of our understanding of PBC. Best Pract Res Clin Gastroenterol 2018; 34-35:3-9. [PMID: 30343708 DOI: 10.1016/j.bpg.2018.05.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2018] [Accepted: 05/10/2018] [Indexed: 01/31/2023]
Abstract
The discovery of mitochondrial autoantigens recognized by antimitochondrial antibodies (AMAs) in 1987 marked the dawn of a new era in primary biliary cholangitis (PBC) research. Since then, there has been substantial progress in our understanding of PBC partly bestowed by the development of innovative technologies in molecular biology, immunology, and genetics. Here, we review this evolutionary progress in understanding PBC. We now recognize that the epitopes of AMAs, CD4+, and CD8+ T cells are all mapped to the same region of the inner lipoyl domain of pyruvate dehydrogenase complex E2 subunit (PDC-E2), and that intrahepatic biliary epithelial cells (BECs) are exclusively targeted in PBC. BECs express PDC-E2 on apotopes in an immunologically intact form during apoptosis, but not other epithelial cells, which could explain the tissue specificity of PBC. In addition, genetic factors, environmental triggers, and epigenetic modifications play crucial roles in the development of PBC. Intact lipoylated PDC-E2, presumably after modification with xenobiotics such as 2-octynamide or 2-nonyamide that are abundantly present in the environment, is endocytosed by antigen-presenting cells and are presented to CD4+ or CD8+ T cells. An immune complex consisting of PDC-E2 and anti-PDC-E2 autoantibodies cross-present autoantigens in a more efficient manner. Finally, an adenylate uridine-rich element (ARE) Del -/- mouse model has been established, which presents a disease modeling human PBC, including female dominance as one of its most important features, and can be used to dissect the immunopathology of PBC. Expanding our knowledge of the pathology from a very early stage of the disease will provide the key to cure PBC.
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Affiliation(s)
- Atsushi Tanaka
- Department of Medicine, Teikyo University School of Medicine, Tokyo, Japan.
| | - Patrick S C Leung
- Division of Rheumatology Allergy and Clinical Immunology, University of California School of Medicine, Davis, CA, USA.
| | - M Eric Gershwin
- Division of Rheumatology Allergy and Clinical Immunology, University of California School of Medicine, Davis, CA, USA.
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15
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Yin DT, Huang L, Han B, Chen X, Yin SM, Zhou W, Chu J, Liang T, Yun TY, Liu Y. Independent long-term result of robotic thymectomy for myasthenia gravis, a single center experience. J Thorac Dis 2018; 10:321-329. [PMID: 29600063 DOI: 10.21037/jtd.2017.12.07] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Background Robotic thymectomy has been suggested a feasible and safe approach for myasthenia gravis (MG). Few investigations have revealed the independent effect of robotic thymectomy without the confounding impact of immunosuppressive (IM) therapy. Methods Between May 2009 and December 2012, robotic extended thymectomy was carried out for patients with diagnosis of MG. The clinical data, subsequent neurological therapy and postintervention status were collected. Results Data of 37 cases was available for analysis. The mean follow-up was 70.0±13.3 months. The median age was 40 years. Twelve (32.4%) patients kept free of IM therapy, and 25 (67.6%) patients accepted postoperatively. The overall 5-year complete stable remission (CSR) rate was 40.6% and improvement rate was 81.6%. The young (age ≤40) displayed a significant better CSR rate (P=0.015) and a trend of better improvement rate (P=0.050) compared to the old (age >40). Patients without usage of IM therapy showed significant higher CSR rate (P=0.014) and improvement rate (P=0.024) compared to those with usage of IM therapy. Patients with Myasthenia Gravis Foundation of America (MGFA) classes I showed a trend of higher remission rate by multivariate analysis. No significant differences were found for the remission rate according to gender, pathology, and the duration of symptoms. Conclusions The mono-therapy of robotic thymectomy may bring with a satisfactory long-term result for part of MG patients. Precision selection and individualized therapy are of the most importance.
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Affiliation(s)
- Dong-Tao Yin
- Department of Thoracic Surgery, The PLA General Hospital, Beijing 100853, China.,Department of Thoracic Surgery, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Ling Huang
- Department of Neurology, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Bing Han
- Department of Thoracic Surgery, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Xiu Chen
- Department of Thoracic Surgery, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Shi-Min Yin
- Department of Neurology, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Wen Zhou
- Department of Cadre's Ward, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Jian Chu
- Department of Thoracic Surgery, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Tao Liang
- Department of Thoracic Surgery, The General Hospital of the PLA Rocket Force, Beijing 100088, China
| | - Tian-Yang Yun
- Department of Thoracic Surgery, The PLA General Hospital, Beijing 100853, China
| | - Yang Liu
- Department of Thoracic Surgery, The PLA General Hospital, Beijing 100853, China
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16
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The thymidylate synthase enhancer region (TSER) polymorphism increases the risk of thymic lymphoid hyperplasia in patients with Myasthenia Gravis. Gene 2018; 642:376-380. [PMID: 29162511 DOI: 10.1016/j.gene.2017.11.055] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 11/17/2017] [Indexed: 12/27/2022]
Abstract
BACKGROUND Myasthenia Gravis (MG) is caused, in approximately 80% of the patients, by autoantibodies against the nicotinic acetylcholine receptor (AChR). The disease is often associated with pathological changes of the thymus: thymic epithelial tumours are present in about 10-20% of the patients, while up to 80% of the patients with early disease onset have thymic hyperplasia. Folate metabolism is required for the production of DNA precursors and for proper DNA methylation reactions, and impaired folate metabolism has been often associated with cellular growth and cancer. METHODS We investigated if major polymorphisms of folate-related genes, namely MTHFR c.677C>T, MTR c.2756A>G, MTRR c.66A>G and TYMS TSER (a 28-bp tandem repeat in the 5' promoter enhancer region of TYMS) increase the risk of pathological changes of the thymus in AChR+ MG patients. A total of 526 AChR+ MG patients, including 132 patients with normal (involuted) thymus, 146 patients with thymic hyperplasia, and 248 patients with a thymoma were included in the study. Allele and genotype comparisons were performed among the three study groups, after correcting for multiple testing. RESULTS The frequency of the TYMS TSER 3R allele was significantly higher in MG patients with thymic hyperplasia (P=0.004), and the TYMS TSER 3R3R genotype was significantly associated with increased risk of thymic hyperplasia [OR 2.71 (95% CI: 1.34-5.47)]. CONCLUSIONS The 3R allele in the thymidylate synthase promoter enhancer region results in increased protein production, required for the synthesis of DNA precursors. The present study suggests that the TYMS TSER 3R allele increases the risk of thymic lymphoid hyperplasia in AChR+ MG patients.
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Wang Z, Yan Y. Immunopathogenesis in Myasthenia Gravis and Neuromyelitis Optica. Front Immunol 2017; 8:1785. [PMID: 29312313 PMCID: PMC5732908 DOI: 10.3389/fimmu.2017.01785] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2017] [Accepted: 11/29/2017] [Indexed: 12/13/2022] Open
Abstract
Myasthenia gravis (MG) and neuromyelitis optica (NMO) are autoimmune channelopathies of the peripheral neuromuscular junction (NMJ) and central nervous system (CNS) that are mainly mediated by humoral immunity against the acetylcholine receptor (AChR) and aquaporin-4 (AQP4), respectively. The diseases share some common features, including genetic predispositions, environmental factors, the breakdown of tolerance, the collaboration of T cells and B cells, imbalances in T helper 1 (Th1)/Th2/Th17/regulatory T cells, aberrant cytokine and antibody secretion, and complement system activation. However, some aspects of the immune mechanisms are unique. Both targets (AChR and AQP4) are expressed in the periphery and CNS, but MG mainly affects the NMJ in the periphery outside of CNS, whereas NMO preferentially involves the CNS. Inflammatory cells, including B cells and macrophages, often infiltrate the thymus but not the target—muscle in MG, whereas the infiltration of inflammatory cells, mainly polymorphonuclear leukocytes and macrophages, in NMO, is always observed in the target organ—the spinal cord. A review of the common and discrepant characteristics of these two autoimmune channelopathies may expand our understanding of the pathogenic mechanism of both disorders and assist in the development of proper treatments in the future.
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Affiliation(s)
- Zhen Wang
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, College of Life Sciences, Shaanxi Normal University, Xi'an, China.,Tianjin Medical University General Hospital, Tianjin Neurological Institute, Tianjin, China
| | - Yaping Yan
- Key Laboratory of the Ministry of Education for Medicinal Resources and Natural Pharmaceutical Chemistry, National Engineering Laboratory for Resource Development of Endangered Crude Drugs in Northwest China, College of Life Sciences, Shaanxi Normal University, Xi'an, China
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