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Sahi N, Haider L, Chung K, Prados Carrasco F, Kanber B, Samson R, Thompson AJ, Gandini Wheeler-Kingshott CAM, Trip SA, Brownlee W, Ciccarelli O, Barkhof F, Tur C, Houlden H, Chard D. Genetic influences on disease course and severity, 30 years after a clinically isolated syndrome. Brain Commun 2023; 5:fcad255. [PMID: 37841069 PMCID: PMC10576246 DOI: 10.1093/braincomms/fcad255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 08/31/2023] [Accepted: 10/02/2023] [Indexed: 10/17/2023] Open
Abstract
Multiple sclerosis risk has a well-established polygenic component, yet the genetic contribution to disease course and severity remains unclear and difficult to examine. Accurately measuring disease progression requires long-term study of clinical and radiological outcomes with sufficient follow-up duration to confidently confirm disability accrual and multiple sclerosis phenotypes. In this retrospective study, we explore genetic influences on long-term disease course and severity; in a unique cohort of clinically isolated syndrome patients with homogenous 30-year disease duration, deep clinical phenotyping and advanced MRI metrics. Sixty-one clinically isolated syndrome patients [41 female (67%): 20 male (33%)] underwent clinical and MRI assessment at baseline, 1-, 5-, 10-, 14-, 20- and 30-year follow-up (mean age ± standard deviation: 60.9 ± 6.5 years). After 30 years, 29 patients developed relapsing-remitting multiple sclerosis, 15 developed secondary progressive multiple sclerosis and 17 still had a clinically isolated syndrome. Twenty-seven genes were investigated for associations with clinical outcomes [including disease course and Expanded Disability Status Scale (EDSS)] and brain MRI (including white matter lesions, cortical lesions, and brain tissue volumes) at the 30-year follow-up. Genetic associations with changes in EDSS, relapses, white matter lesions and brain atrophy (third ventricular and medullary measurements) over 30 years were assessed using mixed-effects models. HLA-DRB1*1501-positive (n = 26) patients showed faster white matter lesion accrual [+1.96 lesions/year (0.64-3.29), P = 3.8 × 10-3], greater 30-year white matter lesion volumes [+11.60 ml, (5.49-18.29), P = 1.27 × 10-3] and higher annualized relapse rates [+0.06 relapses/year (0.005-0.11), P = 0.031] compared with HLA-DRB1*1501-negative patients (n = 35). PVRL2-positive patients (n = 41) had more cortical lesions (+0.83 [0.08-1.66], P = 0.042), faster EDSS worsening [+0.06 points/year (0.02-0.11), P = 0.010], greater 30-year EDSS [+1.72 (0.49-2.93), P = 0.013; multiple sclerosis cases: +2.60 (1.30-3.87), P = 2.02 × 10-3], and greater risk of secondary progressive multiple sclerosis [odds ratio (OR) = 12.25 (1.15-23.10), P = 0.031] than PVRL2-negative patients (n = 18). In contrast, IRX1-positive (n = 30) patients had preserved 30-year grey matter fraction [+0.76% (0.28-1.29), P = 8.4 × 10-3], lower risk of cortical lesions [OR = 0.22 (0.05-0.99), P = 0.049] and lower 30-year EDSS [-1.35 (-0.87,-3.44), P = 0.026; multiple sclerosis cases: -2.12 (-0.87, -3.44), P = 5.02 × 10-3] than IRX1-negative patients (n = 30). In multiple sclerosis cases, IRX1-positive patients also had slower EDSS worsening [-0.07 points/year (-0.01,-0.13), P = 0.015] and lower risk of secondary progressive multiple sclerosis [OR = 0.19 (0.04-0.92), P = 0.042]. These exploratory findings support diverse genetic influences on pathological mechanisms associated with multiple sclerosis disease course. HLA-DRB1*1501 influenced white matter inflammation and relapses, while IRX1 (protective) and PVRL2 (adverse) were associated with grey matter pathology (cortical lesions and atrophy), long-term disability worsening and the risk of developing secondary progressive multiple sclerosis.
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Affiliation(s)
- Nitin Sahi
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Lukas Haider
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- Department of Biomedical Imaging and Image Guided Therapy, Medical University Vienna, 1090 Vienna, Austria
| | - Karen Chung
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Ferran Prados Carrasco
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- Centre for Medical Image Computing (CMIC), Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Universitat Oberta de Catalunya, 08018 Barcelona, Spain
| | - Baris Kanber
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- Centre for Medical Image Computing (CMIC), Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- Department of Clinical and Experimental Epilepsy, University College London, London WC1N 3BG, UK
| | - Rebecca Samson
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Alan J Thompson
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Claudia A M Gandini Wheeler-Kingshott
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- Department of Brain and Behavioural Sciences, University of Pavia, 27100 Pavia, Italy
- Brain MRI 3T Research Centre, IRCCS Mondino Foundation, 27100 Pavia, Italy
| | - S Anand Trip
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
| | - Wallace Brownlee
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- National Institute for Health and Care Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre, London W1T 7DN, UK
| | - Olga Ciccarelli
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- National Institute for Health and Care Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre, London W1T 7DN, UK
| | - Frederik Barkhof
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- Centre for Medical Image Computing (CMIC), Department of Medical Physics and Biomedical Engineering, University College London, London WC1E 6BT, UK
- National Institute for Health and Care Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre, London W1T 7DN, UK
- Department of Radiology and Nuclear Medicine, VU University Medical Centre, 1081 HV Amsterdam, The Netherlands
| | - Carmen Tur
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- MS Centre of Catalonia (Cemcat), Vall d'Hebron Institute of Research, Vall d'Hebron Barcelona Hospital Campus, 08035 Barcelona, Spain
| | - Henry Houlden
- Department of Neuromuscular Diseases, UCL Queen Square Institute of Neurology, Queen’s Square House, Queen’s Square, London, WC1N 3BG, UK
| | - Declan Chard
- NMR Research Unit, Queen Square Multiple Sclerosis Centre, University College London Queen Square Institute of Neurology, London WC1N 3BG, UK
- National Institute for Health and Care Research (NIHR) University College London Hospitals (UCLH) Biomedical Research Centre, London W1T 7DN, UK
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Abdelbary M, Nolz JC. N-linked glycans: an underappreciated key determinant of T cell development, activation, and function. IMMUNOMETABOLISM (COBHAM, SURREY) 2023; 5:e00035. [PMID: 38027254 PMCID: PMC10662610 DOI: 10.1097/in9.0000000000000035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 10/31/2023] [Indexed: 12/01/2023]
Abstract
N-linked glycosylation is a post-translational modification that results in the decoration of newly synthesized proteins with diverse types of oligosaccharides that originate from the amide group of the amino acid asparagine. The sequential and collective action of multiple glycosidases and glycosyltransferases are responsible for determining the overall size, composition, and location of N-linked glycans that become covalently linked to an asparagine during and after protein translation. A growing body of evidence supports the critical role of N-linked glycan synthesis in regulating many features of T cell biology, including thymocyte development and tolerance, as well as T cell activation and differentiation. Here, we provide an overview of how specific glycosidases and glycosyltransferases contribute to the generation of different types of N-linked glycans and how these post-translational modifications ultimately regulate multiple facets of T cell biology.
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Affiliation(s)
- Mahmoud Abdelbary
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, OR, USA
| | - Jeffrey C. Nolz
- Department of Molecular Microbiology and Immunology, Oregon Health & Science University, Portland, OR, USA
- Department of Cell, Developmental and Cancer Biology, Oregon Health & Science University, Portland, OR, USA
- Department of Dermatology, Oregon Health & Science University, Portland, OR, USA
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Sy M, Newton BL, Pawling J, Hayama KL, Cordon A, Yu Z, Kuhle J, Dennis JW, Brandt AU, Demetriou M. N-acetylglucosamine inhibits inflammation and neurodegeneration markers in multiple sclerosis: a mechanistic trial. J Neuroinflammation 2023; 20:209. [PMID: 37705084 PMCID: PMC10498575 DOI: 10.1186/s12974-023-02893-9] [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: 08/01/2023] [Accepted: 09/07/2023] [Indexed: 09/15/2023] Open
Abstract
BACKGROUND In the demyelinating disease multiple sclerosis (MS), chronic-active brain inflammation, remyelination failure and neurodegeneration remain major issues despite immunotherapy. While B cell depletion and blockade/sequestration of T and B cells potently reduces episodic relapses, they act peripherally to allow persistence of chronic-active brain inflammation and progressive neurological dysfunction. N-acetyglucosamine (GlcNAc) is a triple modulator of inflammation, myelination and neurodegeneration. GlcNAc promotes biosynthesis of Asn (N)-linked-glycans, which interact with galectins to co-regulate the clustering/signaling/endocytosis of multiple glycoproteins simultaneously. In mice, GlcNAc crosses the blood brain barrier to raise N-glycan branching, suppress inflammatory demyelination by T and B cells and trigger stem/progenitor cell mediated myelin repair. MS clinical severity, demyelination lesion size and neurodegeneration inversely associate with a marker of endogenous GlcNAc, while in healthy humans, age-associated increases in endogenous GlcNAc promote T cell senescence. OBJECTIVES AND METHODS An open label dose-escalation mechanistic trial of oral GlcNAc at 6 g (n = 18) and 12 g (n = 16) for 4 weeks was performed in MS patients on glatiramer acetate and not in relapse from March 2016 to December 2019 to assess changes in serum GlcNAc, lymphocyte N-glycosylation and inflammatory markers. Post-hoc analysis examined changes in serum neurofilament light chain (sNfL) as well as neurological disability via the Expanded Disability Status Scale (EDSS). RESULTS Prior to GlcNAc therapy, high serum levels of the inflammatory cytokines IFNγ, IL-17 and IL-6 associated with reduced baseline levels of a marker of endogenous serum GlcNAc. Oral GlcNAc therapy was safe, raised serum levels and modulated N-glycan branching in lymphocytes. Glatiramer acetate reduces TH1, TH17 and B cell activity as well as sNfL, yet the addition of oral GlcNAc dose-dependently lowered serum IFNγ, IL-17, IL-6 and NfL. Oral GlcANc also dose-dependently reduced serum levels of the anti-inflammatory cytokine IL-10, which is increased in the brain of MS patients. 30% of treated patients displayed confirmed improvement in neurological disability, with an average EDSS score decrease of 0.52 points. CONCLUSIONS Oral GlcNAc inhibits inflammation and neurodegeneration markers in MS patients despite concurrent immunomodulation by glatiramer acetate. Blinded studies are required to investigate GlcNAc's potential to control residual brain inflammation, myelin repair and neurodegeneration in MS.
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Affiliation(s)
- Michael Sy
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA
| | - Barbara L Newton
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA
| | - Judy Pawling
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave, Toronto, ON, M5G 1X5, Canada
| | - Ken L Hayama
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA
| | - Andres Cordon
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA
| | - Zhaoxia Yu
- Department of Statistics, Donald Bren School of Information and Computer Sciences, University of California Irvine, Bren Hall 2019, Irvine, CA, 92697, USA
| | - Jens Kuhle
- Department of Neurology, University Hospital Basel, Mittlere Strasse 83, 4056, Basel, Switzerland
- Multiple Sclerosis Centre and Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB), Departments of Biomedicine and Clinical Research, University Hospital and University of Basel, Basel, Switzerland
| | - James W Dennis
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, 600 University Ave, Toronto, ON, M5G 1X5, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, ON, M5S 1A8, Canada
| | - Alexander U Brandt
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA
| | - Michael Demetriou
- Department of Neurology, University of California Irvine, 208 Sprague Hall, Mail Code 4032, Irvine, CA, 92697, USA.
- Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, USA.
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Loomis SJ, Sadhu N, Fisher E, Gafson AR, Huang Y, Yang C, Hughes EE, Marshall E, Herman A, John S, Runz H, Jia X, Bhangale T, Bronson PG. Genome-wide study of longitudinal brain imaging measures of multiple sclerosis progression across six clinical trials. Sci Rep 2023; 13:14313. [PMID: 37652990 PMCID: PMC10471679 DOI: 10.1038/s41598-023-41099-0] [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: 03/07/2023] [Accepted: 08/22/2023] [Indexed: 09/02/2023] Open
Abstract
While the genetics of MS risk susceptibility are well-described, and recent progress has been made on the genetics of disease severity, the genetics of disease progression remain elusive. We therefore investigated the genetic determinants of MS progression on longitudinal brain MRI: change in brain volume (BV) and change in T2 lesion volume (T2LV), reflecting progressive tissue loss and increasing disease burden, respectively. We performed genome-wide association studies of change in BV (N = 3401) and change in T2LV (N = 3513) across six randomized clinical trials from Biogen and Roche/Genentech: ADVANCE, ASCEND, DECIDE, OPERA I & II, and ORATORIO. Analyses were adjusted for randomized treatment arm, age, sex, and ancestry. Results were pooled in a meta-analysis, and were evaluated for enrichment of MS risk variants. Variant colocalization and cell-specific expression analyses were performed using published cohorts. The strongest peaks were in PTPRD (rs77321193-C/A, p = 3.9 × 10-7) for BV change, and NEDD4L (rs11398377-GC/G, p = 9.3 × 10-8) for T2LV change. Evidence of colocalization was observed for NEDD4L, and both genes showed increased expression in neuronal and/or glial populations. No association between MS risk variants and MRI outcomes was observed. In this unique, precompetitive industry partnership, we report putative regions of interest in the neurodevelopmental gene PTPRD, and the ubiquitin ligase gene NEDD4L. These findings are distinct from known MS risk genetics, indicating an added role for genetic progression analyses and informing drug discovery.
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A genetic correlation and bivariate genome-wide association study of grip strength and depression. PLoS One 2022; 17:e0278392. [PMID: 36520780 PMCID: PMC9754196 DOI: 10.1371/journal.pone.0278392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2022] [Accepted: 11/15/2022] [Indexed: 12/23/2022] Open
Abstract
Grip strength is an important biomarker reflecting muscle strength, and depression is a psychiatric disorder all over the world. Several studies found a significant inverse association between grip strength and depression, and there is also evidence for common physiological mechanisms between them. We used twin data from Qingdao, China to calculate genetic correlations, and we performed a bivariate GWAS to explore potential SNPs, genes, and pathways in common between grip strength and depression. 139 pairs of Dizygotic twins were used for bivariate GWAS. VEAGSE2 and PASCAL software were used for gene-based analysis and pathway enrichment analysis, respectively. And the resulting SNPs were subjected to eQTL analysis and pleiotropy analysis. The genetic correlation coefficient between grip strength and depression was -0.41 (-0.96, -0.15). In SNP-based analysis, 7 SNPs exceeded the genome-wide significance level (P<5×10-8) and a total of 336 SNPs reached the level of suggestive significance (P<1×10-5). Gene-based analysis and pathway-based analysis identified genes and pathways related to muscle strength and the nervous system. The results of eQTL analysis were mainly enriched in tissues such as the brain, thyroid, and skeletal muscle. Pleiotropy analysis shows that 9 of the 15 top SNPs were associated with both grip strength and depression. In conclusion, this bivariate GWAS identified potentially common pleiotropic SNPs, genes, and pathways in grip strength and depression.
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Durda P, Raffield LM, Lange EM, Olson NC, Jenny NS, Cushman M, Deichgraeber P, Grarup N, Jonsson A, Hansen T, Mychaleckyj JC, Psaty BM, Reiner AP, Tracy RP, Lange LA. Circulating Soluble CD163, Associations With Cardiovascular Outcomes and Mortality, and Identification of Genetic Variants in Older Individuals: The Cardiovascular Health Study. J Am Heart Assoc 2022; 11:e024374. [PMID: 36314488 PMCID: PMC9673628 DOI: 10.1161/jaha.121.024374] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Background Monocytes/macrophages participate in cardiovascular disease. CD163 (cluster of differentiation 163) is a monocyte/macrophage receptor, and the shed sCD163 (soluble CD163) reflects monocyte/macrophage activation. We examined the association of sCD163 with incident cardiovascular disease events and performed a genome-wide association study to identify sCD163-associated variants. Methods and Results We measured plasma sCD163 in 5214 adults (aged ≥65 years, 58.7% women, 16.2% Black) of the CHS (Cardiovascular Health Study). We used Cox regression models (associations of sCD163 with incident events and mortality); median follow-up was 26 years. Genome-wide association study analyses were stratified on race. Adjusted for age, sex, and race and ethnicity, sCD163 levels were associated with all-cause mortality (hazard ratio [HR], 1.08 [95% CI, 1.04-1.12] per SD increase), cardiovascular disease mortality (HR, 1.15 [95% CI, 1.09-1.21]), incident coronary heart disease (HR, 1.10 [95% CI, 1.04-1.16]), and incident heart failure (HR, 1.18 [95% CI, 1.12-1.25]). When further adjusted (eg, cardiovascular disease risk factors), only incident coronary heart disease lost significance. In European American individuals, genome-wide association studies identified 38 variants on chromosome 2 near MGAT5 (top result rs62165726, P=3.3×10-18),19 variants near chromosome 17 gene ASGR1 (rs55714927, P=1.5×10-14), and 18 variants near chromosome 11 gene ST3GAL4. These regions replicated in the European ancestry ADDITION-PRO cohort, a longitudinal cohort study nested in the Danish arm of the Anglo-Danish-Dutch study of Intensive Treatment Intensive Treatment In peOple with screeNdetcted Diabetes in Primary Care. In Black individuals, we identified 9 variants on chromosome 6 (rs3129781 P=7.1×10-9) in the HLA region, and 3 variants (rs115391969 P=4.3×10-8) near the chromosome 16 gene MYLK3. Conclusions Monocyte function, as measured by sCD163, may be predictive of overall and cardiovascular-specific mortality and incident heart failure.
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Affiliation(s)
- Peter Durda
- Department of Pathology and Laboratory MedicineLarner College of Medicine, University of VermontBurlingtonVT
| | | | - Ethan M. Lange
- Division of Biomedical Informatics and Personalized Medicine, Department of MedicineUniversity of Colorado Anschutz Medical CampusAuroraCO
| | - Nels C. Olson
- Department of Pathology and Laboratory MedicineLarner College of Medicine, University of VermontBurlingtonVT
| | - Nancy Swords Jenny
- Department of Pathology and Laboratory MedicineLarner College of Medicine, University of VermontBurlingtonVT
| | - Mary Cushman
- Department of Pathology and Laboratory MedicineLarner College of Medicine, University of VermontBurlingtonVT,Department of MedicineLarner College of Medicine, University of VermontBurlingtonVT
| | - Pia Deichgraeber
- Steno Diabetes CenterAarhus University HospitalAarhusDenmark,Department of Endocrinology and Internal MedicineAarhus University HospitalAarhusDenmark
| | - Niels Grarup
- Novo Nordisk Foundation Center for Basic Metabolic ResearchCopenhagenDenmark
| | - Anna Jonsson
- Novo Nordisk Foundation Center for Basic Metabolic ResearchCopenhagenDenmark
| | - Torben Hansen
- Novo Nordisk Foundation Center for Basic Metabolic ResearchCopenhagenDenmark
| | | | - Bruce M. Psaty
- Cardiovascular Health Research Unit, Departments of Medicine, Epidemiology and Health ServicesUniversity of WashingtonSeattleWA
| | - Alex P. Reiner
- Department of EpidemiologyUniversity of WashingtonSeattleWA
| | - Russell P. Tracy
- Department of Pathology and Laboratory MedicineLarner College of Medicine, University of VermontBurlingtonVT,Department of BiochemistryLarner College of Medicine, University of VermontBurlingtonVT
| | - Leslie A. Lange
- Division of Biomedical Informatics and Personalized Medicine, Department of MedicineUniversity of Colorado Anschutz Medical CampusAuroraCO
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Qin X, Chiang CWK, Gaggiotti OE. Deciphering signatures of natural selection via deep learning. Brief Bioinform 2022; 23:6686736. [PMID: 36056746 PMCID: PMC9487700 DOI: 10.1093/bib/bbac354] [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: 05/19/2022] [Revised: 07/11/2022] [Accepted: 07/28/2022] [Indexed: 11/12/2022] Open
Abstract
Identifying genomic regions influenced by natural selection provides fundamental insights into the genetic basis of local adaptation. However, it remains challenging to detect loci under complex spatially varying selection. We propose a deep learning-based framework, DeepGenomeScan, which can detect signatures of spatially varying selection. We demonstrate that DeepGenomeScan outperformed principal component analysis- and redundancy analysis-based genome scans in identifying loci underlying quantitative traits subject to complex spatial patterns of selection. Noticeably, DeepGenomeScan increases statistical power by up to 47.25% under nonlinear environmental selection patterns. We applied DeepGenomeScan to a European human genetic dataset and identified some well-known genes under selection and a substantial number of clinically important genes that were not identified by SPA, iHS, Fst and Bayenv when applied to the same dataset.
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Affiliation(s)
- Xinghu Qin
- Centre for Biological Diversity, Sir Harold Mitchell Building, University of St Andrews, Fife, KY16 9TF, UK
| | - Charleston W K Chiang
- Center for Genetic Epidemiology, Department of Population and Public Health Sciences, Keck School of Medicine & Department of Quantitative and Computational Biology, University of Southern California, USA
| | - Oscar E Gaggiotti
- Centre for Biological Diversity, Sir Harold Mitchell Building, University of St Andrews, Fife, KY16 9TF, UK
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Nova A, Baldrighi GN, Fazia T, Graziano F, Saddi V, Piras M, Beecham A, McCauley JL, Bernardinelli L. Heritability Estimation of Multiple Sclerosis Related Plasma Protein Levels in Sardinian Families with Immunochip Genotyping Data. LIFE (BASEL, SWITZERLAND) 2022; 12:life12071101. [PMID: 35888189 PMCID: PMC9317284 DOI: 10.3390/life12071101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Revised: 07/19/2022] [Accepted: 07/20/2022] [Indexed: 11/25/2022]
Abstract
This work aimed at estimating narrow-sense heritability, defined as the proportion of the phenotypic variance explained by the sum of additive genetic effects, via Haseman–Elston regression for a subset of 56 plasma protein levels related to Multiple Sclerosis (MS). These were measured in 212 related individuals (with 69 MS cases and 143 healthy controls) obtained from 20 Sardinian families with MS history. Using pedigree information, we found seven statistically significant heritable plasma protein levels (after multiple testing correction), i.e., Gc (h2 = 0.77; 95%CI: 0.36, 1.00), Plat (h2 = 0.70; 95%CI: 0.27, 0.95), Anxa1 (h2 = 0.68; 95%CI: 0.27, 1.00), Sod1 (h2 = 0.58; 95%CI: 0.18, 0.96), Irf8 (h2 = 0.56; 95%CI: 0.19, 0.99), Ptger4 (h2 = 0.45; 95%CI: 0.10, 0.96), and Fadd (h2 = 0.41; 95%CI: 0.06, 0.84). A subsequent analysis was performed on these statistically significant heritable plasma protein levels employing Immunochip genotyping data obtained in 155 healthy controls (92 related and 63 unrelated); we found a meaningful proportion of heritable plasma protein levels’ variability explained by a small set of SNPs. Overall, the results obtained, for these seven MS-related proteins, emphasized a high additive genetic variance component explaining plasma levels’ variability.
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Affiliation(s)
- Andrea Nova
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (G.N.B.); (T.F.); (L.B.)
- Correspondence:
| | - Giulia Nicole Baldrighi
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (G.N.B.); (T.F.); (L.B.)
| | - Teresa Fazia
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (G.N.B.); (T.F.); (L.B.)
| | - Francesca Graziano
- Centre of Biostatistics for Clinical Epidemiology, University of Milano-Bicocca, 20900 Monza, Italy;
- School of Medicine and Surgery, University of Milano-Bicocca, 20900 Monza, Italy
| | - Valeria Saddi
- Divisione di Neurologia, Presidio Ospedaliero S. Francesco, ASL Numero 3 Nuoro, 08100 Nuoro, Italy; (V.S.); (M.P.)
| | - Marialuisa Piras
- Divisione di Neurologia, Presidio Ospedaliero S. Francesco, ASL Numero 3 Nuoro, 08100 Nuoro, Italy; (V.S.); (M.P.)
| | - Ashley Beecham
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33146, USA; (A.B.); (J.L.M.)
- Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Jacob L. McCauley
- John P. Hussman Institute for Human Genomics, Miller School of Medicine, University of Miami, Miami, FL 33146, USA; (A.B.); (J.L.M.)
- Dr. John T. Macdonald Foundation Department of Human Genetics, Miller School of Medicine, University of Miami, Miami, FL 33136, USA
| | - Luisa Bernardinelli
- Department of Brain and Behavioral Sciences, University of Pavia, 27100 Pavia, Italy; (G.N.B.); (T.F.); (L.B.)
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Cawley NX, Lyons AT, Abebe D, Luke R, Yerger J, Telese R, Wassif CA, Bailey-Wilson JE, Porter FD. Complex N-Linked Glycosylation: A Potential Modifier of Niemann-Pick Disease, Type C1 Pathology. Int J Mol Sci 2022; 23:ijms23095082. [PMID: 35563467 PMCID: PMC9103943 DOI: 10.3390/ijms23095082] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2022] [Revised: 04/15/2022] [Accepted: 04/20/2022] [Indexed: 11/16/2022] Open
Abstract
Complex asparagine-linked glycosylation plays key roles in cellular functions, including cellular signaling, protein stability, and immune response. Previously, we characterized the appearance of a complex asparagine-linked glycosylated form of lysosome-associated membrane protein 1 (LAMP1) in the cerebellum of Npc1-/- mice. This LAMP1 form was found on activated microglia, and its appearance correlated both spatially and temporally with cerebellar Purkinje neuron loss. To test the importance of complex asparagine-linked glycosylation in NPC1 pathology, we generated NPC1 knock-out mice deficient in MGAT5, a key Golgi-resident glycosyl transferase involved in complex asparagine-linked glycosylation. Our results show that Mgat5-/-:Npc1-/- mice were smaller than Mgat5+/+:Npc1-/- mice, and exhibited earlier NPC1 disease onset and reduced lifespan. Western blot and lectin binding analyses of cerebellar extracts confirmed the reduction in complex asparagine-linked glycosylation, and the absence of the hyper-glycosylated LAMP1 previously observed. Western blot analysis of cerebellar extracts demonstrated reduced calbindin staining in Mgat5-/-:Npc1-/- mice compared to Mgat5+/+:Npc1-/- mutant mice, and immunofluorescent staining of cerebellar sections indicated decreased levels of Purkinje neurons and increased astrogliosis in Mgat5-/-:Npc1-/- mice. Our results suggest that reduced asparagine-linked glycosylation increases NPC1 disease severity in mice, and leads to the hypothesis that mutations in genes involved in asparagine-linked glycosylation may contribute to disease severity progression in individuals with NPC1. To examine this with respect to MGAT5, we analyzed 111 NPC1 patients for two MGAT5 SNPs associated with multiple sclerosis; however, we did not identify an association with NPC1 phenotypic severity.
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Affiliation(s)
- Niamh X. Cawley
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Anna T. Lyons
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Daniel Abebe
- Research Animal Management Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, MD 20892, USA;
| | - Rachel Luke
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Julia Yerger
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Rebecca Telese
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Christopher A. Wassif
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
| | - Joan E. Bailey-Wilson
- Computational and Statistical Genomics Branch, National Human Genome Research Institute, National Institutes of Health, Department of Health and Human Services, Baltimore, MD 21224, USA;
| | - Forbes D. Porter
- Division of Translational Medicine, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA; (N.X.C.); (A.T.L.); (R.L.); (J.Y.); (R.T.); (C.A.W.)
- Correspondence: ; Tel.: +301-435-4432
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10
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Alves I, Fernandes Â, Santos-Pereira B, Azevedo CM, Pinho SS. Glycans as a key factor in self and non-self discrimination: Impact on the breach of immune tolerance. FEBS Lett 2022; 596:1485-1502. [PMID: 35383918 DOI: 10.1002/1873-3468.14347] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/17/2022] [Accepted: 03/29/2022] [Indexed: 11/09/2022]
Abstract
Glycans are carbohydrates that are made by all organisms and covalently conjugated to other biomolecules. Glycans cover the surface of both human cells and pathogens and are fundamental to defining the identity of a cell or an organism, thereby contributing to discriminating self from non-self. As such, glycans are a class of "Self-Associated Molecular Patterns" that can fine-tune host inflammatory processes. In fact, glycans can be sensed and recognized by a variety of glycan-binding proteins (GBP) expressed by immune cells, such as galectins, siglecs and C-type lectins, which recognize changes in the cellular glycosylation, instructing both pro-inflammatory or anti-inflammatory responses. In this review, we introduce glycans as cell-identification structures, discussing how glycans modulate host-pathogen interactions and how they can fine-tune inflammatory processes associated with infection, inflammation and autoimmunity. Finally, from the clinical standpoint, we discuss how glycoscience research can benefit life sciences and clinical medicine by providing a source of valuable biomarkers and therapeutic targets for immunity.
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Affiliation(s)
- Inês Alves
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal
| | - Ângela Fernandes
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal
| | - Beatriz Santos-Pereira
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal
| | - Catarina M Azevedo
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar, University of Porto, Portugal
| | - Salomé S Pinho
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar, University of Porto, Portugal
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11
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Genetics and functional genomics of multiple sclerosis. Semin Immunopathol 2022; 44:63-79. [PMID: 35022889 DOI: 10.1007/s00281-021-00907-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2021] [Accepted: 12/13/2021] [Indexed: 12/14/2022]
Abstract
Multiple sclerosis (MS) is an inflammatory neurodegenerative disease with genetic predisposition. Over the last decade, genome-wide association studies with increasing sample size led to the discovery of robustly associated genetic variants at an exponential rate. More than 200 genetic loci have been associated with MS susceptibility and almost half of its heritability can be accounted for. However, many challenges and unknowns remain. Definitive studies of disease progression and endophenotypes are yet to be performed, whereas the majority of the identified MS variants are not yet functionally characterized. Despite these shortcomings, the unraveling of MS genetics has opened up a new chapter on our understanding MS causal mechanisms.
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12
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Brandt AU, Sy M, Bellmann-Strobl J, Newton BL, Pawling J, Zimmermann HG, Yu Z, Chien C, Dörr J, Wuerfel JT, Dennis JW, Paul F, Demetriou M. Association of a Marker of N-Acetylglucosamine With Progressive Multiple Sclerosis and Neurodegeneration. JAMA Neurol 2021; 78:842-852. [PMID: 33970182 PMCID: PMC8111565 DOI: 10.1001/jamaneurol.2021.1116] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Question Is the serum concentration of N-acetylglucosamine (GlcNAc) altered in patients with multiple sclerosis? Findings This cross-sectional study found that patients with a progressive multiple sclerosis subtype and more severe disease have reduced serum levels of a marker of GlcNAc. In addition, GlcNAc is a rate-limiting substrate for N-glycan branching, which has been shown to regulate immunoactivity and myelination. Meaning This study suggests that GlcNAc and N-glycan branching are associated with multiple sclerosis in general and progressive multiple sclerosis in particular. Importance N-glycan branching modulates cell surface receptor availability, and its deficiency in mice promotes inflammatory demyelination, reduced myelination, and neurodegeneration. N-acetylglucosamine (GlcNAc) is a rate-limiting substrate for N-glycan branching, but, to our knowledge, endogenous serum levels in patients with multiple sclerosis (MS) are unknown. Objective To investigate a marker of endogenous serum GlcNAc levels in patients with MS. Design, Setting, and Participants A cross-sectional discovery study and cross-sectional confirmatory study were conducted at 2 academic MS centers in the US and Germany. The discovery study recruited 54 patients with MS from an outpatient clinic as well as 66 healthy controls between April 20, 2010, and June 21, 2013. The confirmatory study recruited 180 patients with MS from screening visits at an academic MS study center between April 9, 2007, and February 29, 2016. Serum samples were analyzed from December 2, 2013, to March 2, 2015. Statistical analysis was performed from February 23, 2020, to March 18, 2021. Main Outcomes and Measures Serum levels of GlcNAc plus its stereoisomers, termed N-acetylhexosamine (HexNAc), were assessed using targeted tandem mass spectroscopy. Secondary outcomes (confirmatory study) comprised imaging and clinical disease markers. Results The discovery cohort included 66 healthy controls (38 women; mean [SD] age, 42 [20] years), 33 patients with relapsing-remitting MS (RRMS; 25 women; mean [SD] age, 50 [11] years), and 21 patients with progressive MS (PMS; 14 women; mean [SD] age, 55 [7] years). The confirmatory cohort included 125 patients with RRMS (83 women; mean [SD] age, 40 [9] years) and 55 patients with PMS (22 women; mean [SD] age, 49 [80] years). In the discovery cohort, the mean (SD) serum level of GlcNAc plus its stereoisomers (HexNAc) was 710 (174) nM in healthy controls and marginally reduced in patients with RRMS (mean [SD] level, 682 [173] nM; P = .04), whereas patients with PMS displayed markedly reduced levels compared with healthy controls (mean [SD] level, 548 [101] nM; P = 9.55 × 10−9) and patients with RRMS (P = 1.83 × 10−4). The difference between patients with RRMS (mean [SD] level, 709 [193] nM) and those with PMS (mean [SD] level, 405 [161] nM; P = 7.6 × 10−18) was confirmed in the independent confirmatory cohort. Lower HexNAc serum levels correlated with worse expanded disability status scale scores (ρ = –0.485; P = 4.73 × 10−12), lower thalamic volume (t = 1.7; P = .04), and thinner retinal nerve fiber layer (B = 0.012 [SE = 7.5 × 10−11]; P = .008). Low baseline serum HexNAc levels correlated with a greater percentage of brain volume loss at 18 months (t = 1.8; P = .04). Conclusions and Relevance This study suggests that deficiency of GlcNAc plus its stereoisomers (HexNAc) may be a biomarker for PMS. Previous preclinical, human genetic, and ex vivo human mechanistic studies revealed that N-glycan branching and/or GlcNAc may reduce proinflammatory responses, promote myelin repair, and decrease neurodegeneration. Combined, the data suggest that GlcNAc deficiency may be associated with progressive disease and neurodegeneration in patients with MS.
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Affiliation(s)
- Alexander U Brandt
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Department of Neurology, University of California, Irvine, Irvine.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Michael Sy
- Department of Neurology, University of California, Irvine, Irvine
| | - Judith Bellmann-Strobl
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Barbara L Newton
- Department of Neurology, University of California, Irvine, Irvine
| | - Judy Pawling
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Toronto, Ontario, Canada
| | - Hanna G Zimmermann
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Zhaoxia Yu
- Department of Statistics, University of California, Irvine, Irvine
| | - Claudia Chien
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Jan Dörr
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Jens Th Wuerfel
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Medical Image Analysis Center, Department of Biomedical Engineering, University Basel, Basel, Switzerland
| | - James W Dennis
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Toronto, Ontario, Canada.,Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
| | - Friedemann Paul
- Experimental and Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, and Max Delbrück Center for Molecular Medicine, Berlin, Germany.,NeuroCure Clinical Research Center, Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Berlin, Germany
| | - Michael Demetriou
- Department of Neurology, University of California, Irvine, Irvine.,Department of Microbiology and Molecular Genetics, University of California, Irvine, Irvine
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13
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Genetic Variants of the MGAT5 Gene Are Functionally Implicated in the Modulation of T Cells Glycosylation and Plasma IgG Glycome Composition in Ulcerative Colitis. Clin Transl Gastroenterol 2021; 11:e00166. [PMID: 32352685 PMCID: PMC7263653 DOI: 10.14309/ctg.0000000000000166] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
The impact of genetic variants (single nucleotide polymorphisms [SNPs]) in the clinical heterogeneity of ulcerative colitis (UC) remains unclear. We showed that patients with UC exhibit a deficiency in MGAT5 glycogene transcription in intestinal T cells associated with a hyperimmune response. Herein, we evaluated whether MGAT5 SNPs might functionally impact on T cells glycosylation and plasma IgG glycome in patients with UC, as well as in UC clinical outcomes.
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14
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Sy M, Brandt AU, Lee SU, Newton BL, Pawling J, Golzar A, Rahman AMA, Yu Z, Cooper G, Scheel M, Paul F, Dennis JW, Demetriou M. N-acetylglucosamine drives myelination by triggering oligodendrocyte precursor cell differentiation. J Biol Chem 2021; 295:17413-17424. [PMID: 33453988 PMCID: PMC7762951 DOI: 10.1074/jbc.ra120.015595] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 09/17/2020] [Indexed: 01/11/2023] Open
Abstract
Myelination plays an important role in cognitive development and in demyelinating diseases like multiple sclerosis (MS), where failure of remyelination promotes permanent neuro-axonal damage. Modification of cell surface receptors with branched N-glycans coordinates cell growth and differentiation by controlling glycoprotein clustering, signaling, and endocytosis. GlcNAc is a rate-limiting metabolite for N-glycan branching. Here we report that GlcNAc and N-glycan branching trigger oligodendrogenesis from precursor cells by inhibiting platelet-derived growth factor receptor-α cell endocytosis. Supplying oral GlcNAc to lactating mice drives primary myelination in newborn pups via secretion in breast milk, whereas genetically blocking N-glycan branching markedly inhibits primary myelination. In adult mice with toxin (cuprizone)-induced demyelination, oral GlcNAc prevents neuro-axonal damage by driving myelin repair. In MS patients, endogenous serum GlcNAc levels inversely correlated with imaging measures of demyelination and microstructural damage. Our data identify N-glycan branching and GlcNAc as critical regulators of primary myelination and myelin repair and suggest that oral GlcNAc may be neuroprotective in demyelinating diseases like MS.
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Affiliation(s)
- Michael Sy
- Department of Neurology, University of California Irvine, Irvine, California, USA
| | - Alexander U Brandt
- Department of Neurology, University of California Irvine, Irvine, California, USA; Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany; NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Sung-Uk Lee
- Department of Neurology, University of California Irvine, Irvine, California, USA
| | - Barbara L Newton
- Department of Neurology, University of California Irvine, Irvine, California, USA
| | - Judy Pawling
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Canada
| | - Autreen Golzar
- Department of Neurology, University of California Irvine, Irvine, California, USA
| | - Anas M A Rahman
- Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Zhaoxia Yu
- Department of Statistics, Donald Bren School of Information and Computer Sciences, University of California Irvine, Irvine, California, USA
| | - Graham Cooper
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany; NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany; Einstein Center for Neurosciences, Berlin, Germany; Department of Experimental Neurology and Center for Stroke Research, Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Michael Scheel
- NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany
| | - Friedemann Paul
- Experimental and Clinical Research Center, Charité - Universitätsmedizin Berlin and Max-Delbrueck-Center for Molecular Medicine, Berlin, Germany; NeuroCure Clinical Research Center, Charité - Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin and Berlin Institute of Health, Berlin, Germany; Department of Experimental Neurology and Center for Stroke Research, Berlin, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - James W Dennis
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, Toronto, Canada; Department of Molecular Genetics, University of Toronto, Toronto, Canada
| | - Michael Demetriou
- Department of Neurology, University of California Irvine, Irvine, California, USA; Department of Microbiology and Molecular Genetics, University of California Irvine, Irvine, California, USA.
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15
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Abstract
In this review, we focus on the metabolism of mammalian glycan-associated monosaccharides, where the vast majority of our current knowledge comes from research done during the 1960s and 1970s. Most monosaccharides enter the cell using distinct, often tissue specific transporters from the SLC2A family. If not catabolized, these monosaccharides can be activated to donor nucleotide sugars and used for glycan synthesis. Apart from exogenous and dietary sources, all monosaccharides and their associated nucleotide sugars can be synthesized de novo, using mostly glucose to produce all nine nucleotide sugars present in human cells. Today, monosaccharides are used as treatment options for a small number of rare genetic disorders and even some common conditions. Here, we cover therapeutic applications of these sugars and highlight biochemical gaps that must be revisited as we go forward.
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Affiliation(s)
- Paulina Sosicka
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Bobby G. Ng
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
| | - Hudson H. Freeze
- Human Genetics Program, Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California 92037, United States
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16
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Sun Y, Li Z, Liang W, Zhang Y, Song W, Song J, Xue K, Wang M, Sun W, Gu J, Li M, Li W. A novel immunochromatographic strips assay for rapid and simple detection of systemic lupus erythematosus. Sci Rep 2020; 10:14178. [PMID: 32843681 PMCID: PMC7447788 DOI: 10.1038/s41598-020-71137-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Accepted: 07/29/2020] [Indexed: 02/06/2023] Open
Abstract
Systemic lupus erythematosus (SLE) is a complex multi-system autoimmune disease. Detection of anti-nuclear antibodies (ANA) is fundamental for the diagnosis of SLE. In the present study, we found that the level of core fucosylation catalyzed by α1,6-fucosyltransferase (Fut8) is markedly up-regulated on immunoglobulin G (IgG) in the sera of SLE patients detected by Aspergillus oryzae lectin (AOL) blot. In sandwich Dot enzyme-linked immunosorbent assay (Dot-ELISA), the core fucosylation level was also found significantly increased in the sera from SLE patients with a higher ANA titer. To establish a rapid and sensitive laboratory test for the diagnosis of SLE, we prokaryotically expressed AOL and C3-D1-C3-D2-C3 of protein G (SpG3), and generate AOL-conjugated colloid gold immunochromatographic strips (ICS). The detection limit of core fucosylated IgG was 10 μg/mL for AOL-conjugated colloid gold ICS. As well as indirect immunofluorescence, the AOL-conjugated colloid gold ICS showed reliable results in the serum of 39 SLE patients. Our results indicated that the AOL-conjugated colloid gold ICS could serve as a rapid test for the detection of ANA and suspected cases of SLE.
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Affiliation(s)
- Yuhan Sun
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Zhi Li
- Clinical Laboratory, Dalian Municipal Central Hospital, 826-Xinan Road, Shahekou District, Dalian, 116033, Liaoning, China
| | - Wei Liang
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Yanlong Zhang
- Department of Wildlife Medicine, College of Wildlife Resources, Northeast Forestry University, 26-Hexing Road, Harbin, 150040, Heilongjiang, China
| | - Wanli Song
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Jiazhe Song
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Kai Xue
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Meiling Wang
- Clinical Laboratory, Dalian Municipal Central Hospital, 826-Xinan Road, Shahekou District, Dalian, 116033, Liaoning, China
| | - Wenying Sun
- Clinical Laboratory, Dalian Municipal Central Hospital, 826-Xinan Road, Shahekou District, Dalian, 116033, Liaoning, China
| | - Jianguo Gu
- Institute of Molecular Biomembrane and Glycobiology, Tohoku Medical and Pharmaceutical University, Sendai, Miyagi, 981-8558, Japan
| | - Ming Li
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China
| | - Wenzhe Li
- College of Basic Medical Science, Dalian Medical University, 9-Western Section, Lvshun South Road, Dalian, 116044, Liaoning, China.
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17
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Mortales CL, Lee SU, Manousadjian A, Hayama KL, Demetriou M. N-Glycan Branching Decouples B Cell Innate and Adaptive Immunity to Control Inflammatory Demyelination. iScience 2020; 23:101380. [PMID: 32745987 PMCID: PMC7398982 DOI: 10.1016/j.isci.2020.101380] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2020] [Revised: 06/10/2020] [Accepted: 07/14/2020] [Indexed: 11/21/2022] Open
Abstract
B cell depletion potently reduces episodes of inflammatory demyelination in multiple sclerosis (MS), predominantly through loss of innate rather than adaptive immunity. However, molecular mechanisms controlling innate versus adaptive B cell function are poorly understood. N-glycan branching, via interactions with galectins, controls endocytosis and signaling of cell surface receptors to control cell function. Here we report that N-glycan branching in B cells dose dependently reduces pro-inflammatory innate responses by titrating decreases in Toll-like receptor-4 (TLR4) and TLR2 surface expression via endocytosis. In contrast, a minimal level of N-glycan branching maximizes surface retention of the B cell receptor (BCR) and the CD19 co-receptor to promote adaptive immunity. Branched N-glycans inhibit antigen presentation by B cells to reduce T helper cell-17 (TH17)/TH1 differentiation and inflammatory demyelination in mice. Thus, N-glycan branching negatively regulates B cell innate function while promoting/maintaining adaptive immunity via BCR, providing an attractive therapeutic target for MS.
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Affiliation(s)
- Christie-Lynn Mortales
- Department of Microbiology & Molecular Genetics, University of California, Irvine, CA 92617, USA
| | - Sung-Uk Lee
- Department of Neurology, University of California, Irvine, CA 92617, USA
| | - Armen Manousadjian
- Department of Neurology, University of California, Irvine, CA 92617, USA
| | - Ken L Hayama
- Department of Microbiology & Molecular Genetics, University of California, Irvine, CA 92617, USA
| | - Michael Demetriou
- Department of Neurology, University of California, Irvine, CA 92617, USA; Department of Microbiology & Molecular Genetics, University of California, Irvine, CA 92617, USA.
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18
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Iacobaeus E, Arrambide G, Amato MP, Derfuss T, Vukusic S, Hemmer B, Tintore M, Brundin L. Aggressive multiple sclerosis (1): Towards a definition of the phenotype. Mult Scler 2020; 26:1352458520925369. [PMID: 32530385 PMCID: PMC7412876 DOI: 10.1177/1352458520925369] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Revised: 04/06/2020] [Accepted: 04/16/2020] [Indexed: 02/06/2023]
Abstract
While the major phenotypes of multiple sclerosis (MS) and relapsing-remitting, primary and secondary progressive MS have been well characterized, a subgroup of patients with an active, aggressive disease course and rapid disability accumulation remains difficult to define and there is no consensus about their management and treatment. The current lack of an accepted definition and treatment guidelines for aggressive MS triggered a 2018 focused workshop of the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) on aggressive MS. The aim of the workshop was to discuss approaches on how to describe and define the disease phenotype and its treatments. Unfortunately, it was not possible to come to consensus on a definition because of unavailable data correlating severe disease with imaging and molecular biomarkers. However, the workshop highlighted the need for future research needed to define this disease subtype while also focusing on its treatment and management. Here, we review previous attempts to define aggressive MS and present characteristics that might, with additional research, eventually help characterize it. A companion paper summarizes data regarding treatment and management.
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Affiliation(s)
- Ellen Iacobaeus
- Department of Clinical Neuroscience, Division of Neurology, Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden
| | - Georgina Arrambide
- Servei de Neurologia-Neuroimmunologia. Centre d’Esclerosi Múltiple de Catalunya, (Cemcat), Vall d’Hebron Institut de Recerca, Hospital Universitari Vall d’Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Maria Pia Amato
- Department NeuroFarBa, University of Florence, Florence, Italy/IRCCS Fondazione Don Carlo Gnocchi, Florence, Italy
| | - Tobias Derfuss
- Departments of Neurology and Biomedicine, University Hospital Basel, University of Basel, Basel, Switzerland
| | - Sandra Vukusic
- Service de neurologie, Sclérose en plaques, Pathologies de la myéline et neuro-inflammation, and Centre de Référence des Maladies Inflammatoires Rares du Cerveau et de la Moelle, Hôpital Neurologique Pierre Wertheimer, Hospices Civils de Lyon, Lyon/Bron, France; Centre des Neurosciences de Lyon, Observatoire Français de la Sclérose en Plaques, INSERM 1028 et CNRS UMR5292, Lyon, France; Université Claude Bernard Lyon 1, Faculté de médecine Lyon Est, Lyon, France
| | - Bernhard Hemmer
- Department of Neurology, Klinikum rechts der Isar, School of Medicine, Technical University of Munich, Munich, Germany; Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Mar Tintore
- Servei de Neurologia-Neuroimmunologia. Centre d’Esclerosi Múltiple de Catalunya, (Cemcat), Vall d’Hebron Institut de Recerca, Hospital Universitari Vall d’Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Lou Brundin
- Department of Clinical Neuroscience, Division of Neurology, Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden
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19
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Fransen NL, Crusius JBA, Smolders J, Mizee MR, van Eden CG, Luchetti S, Remmerswaal EBM, Hamann J, Mason MRJ, Huitinga I. Post-mortem multiple sclerosis lesion pathology is influenced by single nucleotide polymorphisms. Brain Pathol 2020; 30:106-119. [PMID: 31228212 PMCID: PMC6916567 DOI: 10.1111/bpa.12760] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Accepted: 06/10/2019] [Indexed: 12/25/2022] Open
Abstract
Over the last few decades, several common single nucleotide polymorphisms (SNPs) have been identified that correlate with clinical outcome in multiple sclerosis (MS), but the pathogenic mechanisms underlying the clinical effects of these SNPs are unknown. This is in part because of the difficulty in the functional translation of genotype into disease-relevant mechanisms. Building on our recent work showing the association of clinical disease course with post-mortem MS lesion characteristics, we hypothesized that SNPs that correlate with clinical disease course would also correlate with specific MS lesion characteristics in autopsy tissue. To test this hypothesis, 179 MS brain donors from the Netherlands Brain Bank MS autopsy cohort were genotyped for 102 SNPs, selected based on their reported associations with clinical outcome or their associations with genes that show differential gene expression in MS lesions. Three SNPs linked to MS clinical severity showed a significant association between the genotype and either the proportion of active lesions (rs2234978/FAS and rs11957313/KCNIP1) or the proportion of mixed active/inactive lesions (rs8056098/CLEC16A). Three SNPs linked to MS pathology-associated genes showed a significant association with either proportion of active lesions (rs3130253/MOG), incidence of cortical gray matter lesions (rs1064395/NCAN) or the proportion of remyelinated lesions (rs5742909/CTLA4). In addition, rs2234978/FAS T-allele carriers showed increased FAS gene expression levels in perivascular T cells and perilesional oligodendrocytes, cell types that have been implicated in MS lesion formation. Thus, by combining pathological characterization of MS brain autopsy tissue with genetics, we now start to translate genotypes linked to clinical outcomes in MS into mechanisms involved in MS lesion pathogenesis.
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Affiliation(s)
- Nina L. Fransen
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
| | - Jakob B. A. Crusius
- Laboratory for Immunogenetics, Department of Medical Microbiology and Infection ControlAmsterdam UMC, VU UniversityAmsterdamThe Netherlands
| | - Joost Smolders
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
- MS Center CWZ, Department of NeurologyCanisius Wilhelmina HospitalNijmegenThe Netherlands
| | - Mark R. Mizee
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
| | - Corbert G. van Eden
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
| | - Sabina Luchetti
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
| | - Ester B. M. Remmerswaal
- Department of Experimental Immunology, Amsterdam Infection & Immunity InstituteAmsterdam UMC, University of AmsterdamAmsterdamThe Netherlands
- Renal Transplant Unit, Department of Internal Medicine, Amsterdam Infection & Immunity InstituteAmsterdam UMC, University of AmsterdamAmsterdamThe Netherlands
| | - Jörg Hamann
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
- Department of Experimental Immunology, Amsterdam Infection & Immunity InstituteAmsterdam UMC, University of AmsterdamAmsterdamThe Netherlands
| | - Matthew R. J. Mason
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
| | - Inge Huitinga
- Department of NeuroimmunologyThe Netherlands Institute for NeuroscienceAmsterdamThe Netherlands
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20
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Lee SU, Li CF, Mortales CL, Pawling J, Dennis JW, Grigorian A, Demetriou M. Increasing cell permeability of N-acetylglucosamine via 6-acetylation enhances capacity to suppress T-helper 1 (TH1)/TH17 responses and autoimmunity. PLoS One 2019; 14:e0214253. [PMID: 30913278 PMCID: PMC6435169 DOI: 10.1371/journal.pone.0214253] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 03/08/2019] [Indexed: 12/27/2022] Open
Abstract
N-acetylglucosamine (GlcNAc) branching of Asn (N)-linked glycans inhibits pro-inflammatory T cell responses and models of autoimmune diseases such as Multiple Sclerosis (MS). Metabolism controls N-glycan branching in T cells by regulating de novo hexosamine pathway biosynthesis of UDP-GlcNAc, the donor substrate for the Golgi branching enzymes. Activated T cells switch metabolism from oxidative phosphorylation to aerobic glycolysis and glutaminolysis. This reduces flux of glucose and glutamine into the hexosamine pathway, thereby inhibiting de novo UDP-GlcNAc synthesis and N-glycan branching. Salvage of GlcNAc into the hexosamine pathway overcomes this metabolic suppression to restore UDP-GlcNAc synthesis and N-glycan branching, thereby promoting anti-inflammatory T regulatory (Treg) over pro-inflammatory T helper (TH) 17 and TH1 differentiation to suppress autoimmunity. However, GlcNAc activity is limited by the lack of a cell surface transporter and requires high doses to enter cells via macropinocytosis. Here we report that GlcNAc-6-acetate is a superior pro-drug form of GlcNAc. Acetylation of amino-sugars improves cell membrane permeability, with subsequent de-acetylation by cytoplasmic esterases allowing salvage into the hexosamine pathway. Per- and bi-acetylation of GlcNAc led to toxicity in T cells, whereas mono-acetylation at only the 6 > 3 position raised N-glycan branching greater than GlcNAc without inducing significant toxicity. GlcNAc-6-acetate inhibited T cell activation/proliferation, TH1/TH17 responses and disease progression in Experimental Autoimmune Encephalomyelitis (EAE), a mouse model of MS. Thus, GlcNAc-6-Acetate may provide an improved therapeutic approach to raise N-glycan branching, inhibit pro-inflammatory T cell responses and treat autoimmune diseases such as MS.
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Affiliation(s)
- Sung-Uk Lee
- Department of Neurology, University of California, Irvine, Irvine, California, United States of America
- Glixis Therapeutics, LLC, Santa Rosa, California, United States of America
| | - Carey F. Li
- Department of Neurology, University of California, Irvine, Irvine, California, United States of America
| | - Christie-Lynn Mortales
- Department of Microbiology & Molecular Genetics, University of California, Irvine, Irvine, California, United States of America
| | - Judy Pawling
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
| | - James W. Dennis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, Ontario, Canada
- Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - Ani Grigorian
- Glixis Therapeutics, LLC, Santa Rosa, California, United States of America
| | - Michael Demetriou
- Department of Neurology, University of California, Irvine, Irvine, California, United States of America
- Department of Microbiology & Molecular Genetics, University of California, Irvine, Irvine, California, United States of America
- Institute for Immunology, University of California, Irvine, Irvine, California, United States of America
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21
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Pereira MS, Alves I, Vicente M, Campar A, Silva MC, Padrão NA, Pinto V, Fernandes Â, Dias AM, Pinho SS. Glycans as Key Checkpoints of T Cell Activity and Function. Front Immunol 2018; 9:2754. [PMID: 30538706 PMCID: PMC6277680 DOI: 10.3389/fimmu.2018.02754] [Citation(s) in RCA: 96] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Accepted: 11/08/2018] [Indexed: 12/20/2022] Open
Abstract
The immune system is highly controlled and fine-tuned by glycosylation, through the addition of a diversity of carbohydrates structures (glycans) to virtually all immune cell receptors. Despite a relative backlog in understanding the importance of glycans in the immune system, due to its inherent complexity, remarkable findings have been highlighting the essential contributions of glycosylation in the regulation of both innate and adaptive immune responses with important implications in the pathogenesis of major diseases such as autoimmunity and cancer. Glycans are implicated in fundamental cellular and molecular processes that regulate both stimulatory and inhibitory immune pathways. Besides being actively involved in pathogen recognition through interaction with glycan-binding proteins (such as C-type lectins), glycans have been also shown to regulate key pathophysiological steps within T cell biology such as T cell development and thymocyte selection; T cell activity and signaling as well as T cell differentiation and proliferation. These effects of glycans in T cells functions highlight their importance as determinants of either self-tolerance or T cell hyper-responsiveness which ultimately might be implicated in the creation of tolerogenic pathways in cancer or loss of immunological tolerance in autoimmunity. This review discusses how specific glycans (with a focus on N-linked glycans) act as regulators of T cell biology and their implications in disease.
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Affiliation(s)
- Márcia S Pereira
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Institute of Biomedical Sciences of Abel Salazar, University of Porto Porto, Portugal
| | - Inês Alves
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Medical Faculty, University of Porto Porto, Portugal
| | - Manuel Vicente
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Institute of Biomedical Sciences of Abel Salazar, University of Porto Porto, Portugal
| | - Ana Campar
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Institute of Biomedical Sciences of Abel Salazar, University of Porto Porto, Portugal.,Centro Hospitalar do Porto Porto, Portugal
| | - Mariana C Silva
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal
| | - Nuno A Padrão
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Medical Faculty, University of Porto Porto, Portugal
| | - Vanda Pinto
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal
| | - Ângela Fernandes
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal
| | - Ana M Dias
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal
| | - Salomé S Pinho
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP) Porto, Portugal.,Institute for Research and Innovation in Health (I3S) Porto, Portugal.,Medical Faculty, University of Porto Porto, Portugal
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22
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Dias AM, Pereira MS, Padrão NA, Alves I, Marcos-Pinto R, Lago P, Pinho SS. Glycans as critical regulators of gut immunity in homeostasis and disease. Cell Immunol 2018; 333:9-18. [DOI: 10.1016/j.cellimm.2018.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Revised: 07/04/2018] [Accepted: 07/17/2018] [Indexed: 12/19/2022]
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23
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Javor J, Shawkatová I, Ďurmanová V, Párnická Z, Čierny D, Michalik J, Čopíková-Cudráková D, Smahová B, Gmitterová K, Peterajová Ľ, Bucová M. TNFRSF1A polymorphisms and their role in multiple sclerosis susceptibility and severity in the Slovak population. Int J Immunogenet 2018; 45:257-265. [PMID: 30009568 DOI: 10.1111/iji.12388] [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] [Received: 12/28/2017] [Revised: 04/24/2018] [Accepted: 06/13/2018] [Indexed: 12/20/2022]
Abstract
Tumour necrosis factor (TNF)-mediated signalling plays a key role in inflammatory and neurodegenerative processes leading to the development of multiple sclerosis (MS). Recent studies have highlighted the role of tumour necrosis factor receptor superfamily member 1A (TNFRSF1A) gene encoding the type 1 TNF receptor in the genetic predisposition to MS. This study aimed to validate the association of TNFRSF1A rs1800693 and rs4149584 polymorphisms with susceptibility to MS in the Slovak population and analyse their influence on age at disease onset, severity, and disability progression. Polymerase chain reaction-restriction fragment length polymorphism method was used to genotype both TNFRSF1A polymorphisms in 541 MS patients and 724 healthy controls. Logistic regression analysis revealed a significantly increased risk of developing MS for the carriers of rs1800693 C allele (TC + CC vs. TT: pcorr = 0.005; OR = 1.61; 95% CI = 1.23-2.12), irrespective of sex and carriage of the major MS risk allele HLA-DRB1*15:01. On the other hand, no association could be found between rs4149584 and MS risk (GA + AA vs. GG: pcorr = 1.00; OR = 1.25; 95% CI = 0.71-2.21). Moreover, neither polymorphism was significantly associated with age at disease onset, MS Severity Score (MSSS) or MS Progression Index (PI) in any of the inheritance models. In conclusion, our results provide support for a sex- and HLA-DRB1*15:01-independent association of TNFRSF1A rs1800693 SNP with MS susceptibility, but not with age at disease onset, severity or rate of disability accumulation.
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Affiliation(s)
- Juraj Javor
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
| | - Ivana Shawkatová
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
| | - Vladimíra Ďurmanová
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
| | - Zuzana Párnická
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
| | - Daniel Čierny
- Department of Clinical Biochemistry, Jessenius Faculty of Medicine, Comenius University in Bratislava and University Hospital Martin, Martin, Slovakia
| | - Jozef Michalik
- Clinic of Neurology, Jessenius Faculty of Medicine, Comenius University in Bratislava and University Hospital Martin, Martin, Slovakia
| | - Daniela Čopíková-Cudráková
- 1st Department of Neurology, Faculty of Medicine, Comenius University in Bratislava and University Hospital Bratislava, Bratislava, Slovakia
| | - Barbora Smahová
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
| | - Karin Gmitterová
- 2nd Department of Neurology, Faculty of Medicine, Comenius University in Bratislava and University Hospital Bratislava, Bratislava, Slovakia
| | - Ľubica Peterajová
- Haematology Outpatient Clinic, University Hospital Bratislava, Bratislava, Slovakia
| | - Mária Bucová
- Institute of Immunology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia
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24
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Ni Choileain S, Hay J, Thomas J, Williams A, Vermeren MM, Benezech C, Gomez-Salazar M, Hugues OR, Vermeren S, Howie SEM, Dransfield I, Astier AL. TCR-stimulated changes in cell surface CD46 expression generate type 1 regulatory T cells. Sci Signal 2017; 10:10/502/eaah6163. [PMID: 29066539 DOI: 10.1126/scisignal.aah6163] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
A lack of regulatory T cell function is a critical factor in the pathogenesis of autoimmune diseases, such as multiple sclerosis (MS). Ligation of the complement regulatory protein CD46 facilitates the differentiation of T helper 1 (TH1) effector cells into interleukin-10 (IL-10)-secreting type 1 regulatory T cells (Tr1 cells), and this pathway is defective in MS patients. Cleavage of the ectodomain of CD46, which contains three N-glycosylation sites and multiple O-glycosylation sites, enables CD46 to activate T cells. We found that stimulation of the T cell receptor (TCR)-CD3 complex was associated with a reduction in the apparent molecular mass of CD46 in a manner that depended on O-glycosylation. CD3-stimulated changes in CD46 O-glycosylation status reduced CD46 processing and subsequent T cell signaling. During T cell activation, CD46 was recruited to the immune synapse in a manner that required its serine-, threonine-, and proline-rich (STP) region, which is rich in O-glycosylation sites. Recruitment of CD46 to the immune synapse switched T cells from producing the inflammatory cytokine interferon-γ (IFN-γ) to producing IL-10. Furthermore, CD4+ T cells isolated from MS patients did not exhibit a CD3-stimulated reduction in the mass of CD46 and thus showed increased amounts of cell surface CD46. Together, these data suggest a possible mechanism underlying the regulatory function of CD46 on T cells. Our findings may explain why this pathway is defective in patients with MS and provide insights into MS pathogenesis that could help to design future immunotherapies.
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Affiliation(s)
- Siobhan Ni Choileain
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Joanne Hay
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Joelle Thomas
- Université Claude Bernard Lyon I, CNRS UMR 5310-INSERM U1217, F-69100 Lyon, France
| | - Anna Williams
- MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh EH16 4UU, UK
| | - Matthieu M Vermeren
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Cecile Benezech
- UK Centre for Cardiovascular Science, University of Edinburgh, Edinburgh EH16 4TJ, UK
| | - Mario Gomez-Salazar
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Owen R Hugues
- Millipore (U.K.) Limited, Croxley Green Business Park, Watford, Hertfordshire WD18 8ZB, UK
| | - Sonja Vermeren
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Sarah E M Howie
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Ian Dransfield
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK
| | - Anne L Astier
- Medical Research Council (MRC) Centre for Inflammation Research, University of Edinburgh, Queen's Medical Research Institute, Edinburgh EH16 4TJ, UK. .,Centre de Physiopathologie Toulouse-Purpan, INSERM U1043, CNRS U5282, Université de Toulouse, Toulouse F-31300, France
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25
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Zhou Y, Graves JS, Simpson S, Charlesworth JC, Mei IVD, Waubant E, Barcellos LF, Belman A, Krupp L, Lucas R, Ponsonby AL, Taylor BV. Genetic variation in the gene LRP2 increases relapse risk in multiple sclerosis. J Neurol Neurosurg Psychiatry 2017; 88:864-868. [PMID: 28739605 DOI: 10.1136/jnnp-2017-315971] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Revised: 06/21/2017] [Accepted: 06/22/2017] [Indexed: 11/04/2022]
Abstract
BACKGROUND Due to the lack of prospective studies with longitudinal data on relapse, past genetic studies have not attempted to identify genetic factors that predict relapse risk (the primary endpoint of many pivotal clinical trials testing the efficacy of multiple sclerosis (MS) disease-modifying drugs) at a genome-wide scale. METHODS We conducted a genome-wide association analysis (GWAS) to identify genetic variants that predict MS relapse risk, using a three-stage approach. First, GWAS was conducted using the southern Tasmania MS Longitudinal Study with 141 cases followed prospectively for a mean of 2.3 years. Second, GWAS was conducted using the Ausimmune Longitudinal Study with 127 cases having a classic first demyelinating event followed for 5 years from onset. Third, the top hits with p<5.0×10-6 from the first two stages were combined with a longitudinal US paediatric MS cohort with 181 cases followed for 5 years after onset. Predictors of time to relapse were evaluated by a mixed effects Cox model. An inverse variance fixed effects model was then used to undertake a meta-analysis. RESULTS In the pooled results, using these three unique longitudinal MS cohorts, we discovered one novel locus (LRP2; most significant single nucleotide polymorphism rs12988804) that reached genome-wide significance in predicting relapse risk (HR=2.18, p=3.30×10-8). LRP2 is expressed on the surface of many central nervous system cells including neurons and oligodendrocytes and is a critical receptor in axonal guidance. CONCLUSIONS The finding of a genetic locus that has extensive effects on neuronal development and repair is of interest as a potential modulator of MS disease course.
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Affiliation(s)
- Yuan Zhou
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Jennifer S Graves
- Department of Neurology, University of California, San Francisco, USA
| | - Steve Simpson
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.,Institute for Health and Ageing, Australian Catholic University, Melbourne, Australia
| | - Jac C Charlesworth
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | - Ingrid van der Mei
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
| | | | - Lisa F Barcellos
- Division of Epidemiology, School of Public Health, University of California, Berkeley, USA
| | - Anita Belman
- Stonybrook University, Stonybrook, New York, USA
| | | | - Robyn Lucas
- National Centre for Epidemiology and Population Health, Research School of Population Health, Australian National University, Canberra, Australia
| | - Anne-Louise Ponsonby
- Murdoch Childrens Research Institute, University of Melbourne, Melbourne, Australia
| | - Bruce V Taylor
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia
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26
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Dardiotis E, Panayiotou E, Provatas A, Christodoulou K, Hadjisavvas A, Antoniades A, Lourbopoulos A, Pantzaris M, Grigoriadis N, Hadjigeorgiou GM, Kyriakides T. Gene variants of adhesion molecules act as modifiers of disease severity in MS. NEUROLOGY-NEUROIMMUNOLOGY & NEUROINFLAMMATION 2017; 4:e350. [PMID: 28473999 PMCID: PMC5405760 DOI: 10.1212/nxi.0000000000000350] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 03/01/2017] [Indexed: 12/30/2022]
Abstract
Objective: To assess the potential effect of variants in genes encoding molecules that are implicated in leukocyte trafficking into the CNS on the clinical phenotype of multiple sclerosis (MS). Methods: A total of 389 Greek MS cases and 336 controls were recruited in 3 MS centers from Cyprus and Greece. We genotyped 147 tagging single nucleotide polymorphisms (SNPs) in 9 genes encoding for P-selectin (SELP), integrins (ITGA4, ITGB1, and ITGB7), adhesion molecules (ICAM1, VCAM1, and MADCAM1), fibronectin 1 (FN1), and osteopontin (SPP1) involved in lymphocyte adhesion and trafficking into the CNS. Clinical end points of the study were age at MS onset and MS severity as measured by the Multiple Sclerosis Severity Score. Permutation testing was applied to all analyses. Results: SNPs rs6721763 of the ITGA4 and rs6532040 of the SPP1 were found to significantly influence disease severity (permutation p values: 3.00e-06 and 0.009884, respectively). SNP rs1250249 of the FN1 had a dose-dependent effect on age at disease onset (permutation p value: 0.0002). Conclusions: This study provides evidence implicating variants encoding adhesion molecules, responsible for lymphocyte adhesion and trafficking within the CNS, as modifiers of MS disease severity. These genetic biomarkers, which can be available at the time of diagnosis, may be used to assess the biological aggressiveness of the disease and thus guide decisions on treatment.
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Affiliation(s)
- Efthimios Dardiotis
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Elena Panayiotou
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Antonios Provatas
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Kyproula Christodoulou
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Andreas Hadjisavvas
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Athos Antoniades
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Athanasios Lourbopoulos
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Marios Pantzaris
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Nikolaos Grigoriadis
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Georgios M Hadjigeorgiou
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
| | - Theodoros Kyriakides
- The Cyprus Institute of Neurology and Genetics (E.D., E.P., K.C., A.H., M.P., T.K.), Nicosia, Cyprus; Department of Neurology (E.D., A.P., G.M.H.), Laboratory of Neurogenetics, University of Thessaly, University Hospital of Larissa; Head of Research and Developments (A.A.), Stremble Ventures LTD, Limassol, Cyprus; and 2nd Department of Neurology (A.L., N.G.), AHEPA University Hospital, Aristotle University of Thessaloniki, Greece
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Jokubaitis VG, Butzkueven H. A genetic basis for multiple sclerosis severity: Red herring or real? Mol Cell Probes 2016; 30:357-365. [PMID: 27546889 DOI: 10.1016/j.mcp.2016.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2016] [Revised: 08/17/2016] [Accepted: 08/17/2016] [Indexed: 01/24/2023]
Abstract
Multiple Sclerosis (MS) is an autoimmune degenerative disease of the central nervous system, characterized by multifocal demyelination and neurodegeneration. The genetic architecture of MS is complex, where genetic risk has been attributed to over 100 polymorphic loci each with small odds ratios. MS is a highly heterogeneous disease with numerous clinical and paraclinical endophenotypes. To-date, no genetic variant has been associated with clinical outcome, however, evidence exists that MS outcomes, like risk, are to an extent also controlled by genetic variation. Here we summarise the current evidence for genetic determination of disease outcomes and make recommendations for future research directions.
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Affiliation(s)
- Vilija G Jokubaitis
- Department of Medicine and Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Australia; Department of Neurology, Royal Melbourne Hospital, Melbourne, Australia.
| | - Helmut Butzkueven
- Department of Medicine and Melbourne Brain Centre at the Royal Melbourne Hospital, University of Melbourne, Australia; Department of Neurology, Royal Melbourne Hospital, Melbourne, Australia; Department of Neurology, Box Hill Hospital, Monash University, Box Hill, Australia
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28
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Decker Y, Schomburg R, Németh E, Vitkin A, Fousse M, Liu Y, Fassbender K. Abnormal galactosylation of immunoglobulin G in cerebrospinal fluid of multiple sclerosis patients. Mult Scler 2016; 22:1794-1803. [DOI: 10.1177/1352458516631036] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2015] [Revised: 01/05/2016] [Accepted: 01/14/2016] [Indexed: 11/15/2022]
Abstract
Background: Glycosylation alterations have been associated with the development of several human diseases and their animal models, including multiple sclerosis. Objectives: We aimed to determine whether immunoglobulin G galactosylation might be changed in multiple sclerosis. Methods: Immunoglobulin G was isolated from serum and cerebrospinal fluid of patients with multiple sclerosis or viral meningitis and control patients without history of inflammatory or autoimmune disease. A lectin-based assay was used to investigate potential galactosylation modifications of immunoglobulin G. Results and conclusion: Galactosylation of immunoglobulin G isolated from cerebrospinal fluid of control patients was found to be age- and gender-dependent. In addition, immunoglobulin G galactosylation was significantly altered in cerebrospinal fluid but not in serum of multiple sclerosis patients. Furthermore, this modification was correlated with an active progression of multiple sclerosis. Finally, the loss of galactosyl moieties was not simply associated with inflammation as no such change was detected in viral meningitis patients characterized by brain inflammation.
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Affiliation(s)
- Yann Decker
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Robert Schomburg
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Eszter Németh
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Artem Vitkin
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Mathias Fousse
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Yang Liu
- Department of Neurology, Saarland University, Homburg/Saar, Germany
| | - Klaus Fassbender
- Department of Neurology, Saarland University, Homburg/Saar, Germany
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29
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Feldcamp L, Doucet JS, Pawling J, Fadel MP, Fletcher PJ, Maunder R, Dennis JW, Wong AHC. Mgat5 modulates the effect of early life stress on adult behavior and physical health in mice. Behav Brain Res 2016; 312:253-64. [PMID: 27329152 DOI: 10.1016/j.bbr.2016.06.033] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2016] [Revised: 06/05/2016] [Accepted: 06/15/2016] [Indexed: 12/20/2022]
Abstract
Psychosocial adversity in early life increases the likelihood of mental and physical illness, but the underlying mechanisms are poorly understood. Mgat5 is an N-acetylglucosaminyltransferase in the Golgi pathway that remodels the N-glycans of glycoproteins at the cell surface. Mice lacking Mgat5 display conditional phenotypes in behaviour, immunity, metabolism, aging and cancer susceptibility. Here we investigated potential gene-environment interactions between Mgat5 and early life adversity on behaviour and physiological measures of physical health. Mgat5(-/-) mutant and Mgat5(+/+) wild-type C57Bl/6 littermates were subject to maternal separation or foster rearing as an early life stressor, in comparison to control mice reared normally. We found an interaction between Mgat5 genotype and maternal rearing condition in which Mgat5(-/-) mice subjected to early life stress had lower glucose levels and higher bone density. Mgat5(-/-) genotype was also associated with less immobility in the forced swim test and greater sucrose consumption, consistent with a less depression-like phenotype. Cortical neuron dendrite spine density and branching was altered by Mgat5 deletion as well. In general, Mgat5 genotype affects both behaviour and physical outcomes in response to early life stress, suggesting some shared pathways for both in this model. These results provide a starting point for studying the mechanisms by which protein N-glycosylation mediates the effects of early life adversity.
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Affiliation(s)
- Laura Feldcamp
- Institute of Medical Science, University of Toronto, Medical Sciences Building, 1 King's College Circle, Room 2374, Toronto, Ontario, M5S 1A8, Canada; Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada
| | - Jean-Sebastien Doucet
- Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada
| | - Judy Pawling
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Ave., Toronto, Ontario, M5G 1X5, Canada
| | - Marc P Fadel
- Ontario Shores Centre for Mental Health Sciences, 700 Gordon St, Whitby, Ontario, Canada; Department of Psychiatry, University of Toronto, 250 College Street, 8th Floor, Toronto, Ontario, M5T 1R8, Canada
| | - Paul J Fletcher
- Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada
| | - Robert Maunder
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Ave., Toronto, Ontario, M5G 1X5, Canada; Department of Psychiatry, University of Toronto, 250 College Street, 8th Floor, Toronto, Ontario, M5T 1R8, Canada
| | - James W Dennis
- Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, 600 University Ave., Toronto, Ontario, M5G 1X5, Canada; Department of Molecular Genetics, University of Toronto, Medical Sciences Building, Room 4386, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada; Department of Laboratory Medicine and Pathology, University of Toronto, Medical Sciences Building, 1 King's College Circle, 6th Floor, Toronto, Ontario, M5S 1A8, Canada
| | - Albert H C Wong
- Institute of Medical Science, University of Toronto, Medical Sciences Building, 1 King's College Circle, Room 2374, Toronto, Ontario, M5S 1A8, Canada; Campbell Family Mental Health Research Institute, Center for Addiction and Mental Health, 250 College Street, Toronto, Ontario, M5T 1R8, Canada; Department of Psychiatry, University of Toronto, 250 College Street, 8th Floor, Toronto, Ontario, M5T 1R8, Canada; Department of Pharmacology, University of Toronto, Medical Sciences Building, Rm 4207, 1 King's College Circle, Toronto, Ontario, M5S 1A8, Canada,.
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Abstract
PURPOSE OF REVIEW Recent studies indicate a role for immune dysregulation in the pathogenesis of multiple sclerosis, an inflammatory demyelinating and degenerative disease of the central nervous system. This review addresses the current mechanisms of immune dysregulation in the development of multiple sclerosis, including the impact of environmental risk factors on immunity in both multiple sclerosis and its animal models. RECENT FINDINGS CD4 T-helper (Th) cells have long been implicated as the main drivers of pathogenesis of multiple sclerosis. However, current studies indicate that multiple sclerosis is largely a heterogeneous disease process, which involves both innate and adaptive immune-mediated inflammatory mechanisms that ultimately contribute to demyelination and neurodegeneration. Therefore, B cells, CD8 T cells, and microglia/macrophages can also play an important role in the immunopathogenesis of multiple sclerosis apart from proinflammatory CD4 Th1/Th17 cell subsets. Furthermore, increasing evidence indicates that environmental risk factors, such as Vitamin D deficiency, Epstein-Barr virus, smoking, Western diet, and the commensal microbiota, influence the development of multiple sclerosis through interactions with genetic variants of multiple sclerosis, thus leading to the dysregulation of immune responses. SUMMARY A better understanding of immune-mediated mechanisms in the pathogenesis of multiple sclerosis and the contribution of environmental risk factors toward the development of multiple sclerosis will help further improve therapeutic approaches to prevent disease progression.
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Kato A, Yutani M, Terao M, Kimura A, Itoi S, Murota H, Miyoshi E, Katayama I. Oligosaccharide modification byN-acetylglucosaminyltransferase-V in macrophages are involved in pathogenesis of bleomycin-induced scleroderma. Exp Dermatol 2015; 24:585-90. [DOI: 10.1111/exd.12730] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/08/2015] [Indexed: 12/16/2022]
Affiliation(s)
- Arisa Kato
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
- Department of Molecular Biochemistry and Clinical Investigation; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Mizuki Yutani
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
- Department of Molecular Biochemistry and Clinical Investigation; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Mika Terao
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Akihiro Kimura
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
- Department of Molecular Biochemistry and Clinical Investigation; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Saori Itoi
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Hiroyuki Murota
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Eiji Miyoshi
- Department of Molecular Biochemistry and Clinical Investigation; Graduate School of Medicine; Osaka University; Suita Osaka Japan
| | - Ichiro Katayama
- Department of Dermatology; Graduate School of Medicine; Osaka University; Suita Osaka Japan
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Glycans and cancer: role of N-glycans in cancer biomarker, progression and metastasis, and therapeutics. Adv Cancer Res 2015; 126:11-51. [PMID: 25727145 DOI: 10.1016/bs.acr.2014.11.001] [Citation(s) in RCA: 267] [Impact Index Per Article: 29.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Glycosylation is catalyzed by various glycosyltransferase enzymes which are mostly located in the Golgi apparatus in cells. These enzymes glycosylate various complex carbohydrates such as glycoproteins, glycolipids, and proteoglycans. The enzyme activity of glycosyltransferases and their gene expression are altered in various pathophysiological situations including cancer. Furthermore, the activity of glycosyltransferases is controlled by various factors such as the levels of nucleotide sugars, acceptor substrates, nucleotide sugar transporters, chaperons, and endogenous lectin in cancer cells. The glycosylation results in various functional changes of glycoproteins including cell surface receptors and adhesion molecules such as E-cadherin and integrins. These changes confer the unique characteristic phenotypes associated with cancer cells. Therefore, glycans play key roles in cancer progression and treatment. This review focuses on glycan structures, their biosynthetic glycosyltransferases, and their genes in relation to their biological significance and involvement in cancer, especially cancer biomarkers, epithelial-mesenchymal transition, cancer progression and metastasis, and therapeutics. Major N-glycan branching structures which are directly related to cancer are β1,6-GlcNAc branching, bisecting GlcNAc, and core fucose. These structures are enzymatic products of glycosyltransferases, GnT-V, GnT-III, and Fut8, respectively. The genes encoding these enzymes are designated as MGAT5 (Mgat5), MGAT3 (Mgat3), and FUT8 (Fut8) in humans (mice in parenthesis), respectively. GnT-V is highly associated with cancer metastasis, whereas GnT-III is associated with cancer suppression. Fut8 is involved in expression of cancer biomarker as well as in the treatment of cancer. In addition to these enzymes, GnT-IV and GnT-IX (GnT-Vb) will be also discussed in relation to cancer.
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Giacalone G, Clarelli F, Osiceanu AM, Guaschino C, Brambilla P, Sorosina M, Liberatore G, Zauli A, Esposito F, Rodegher M, Ghezzi A, Galimberti D, Patti F, Barizzone N, Guerini F, Martinelli V, Leone M, Comi G, D’Alfonso S, Martinelli Boneschi F. Analysis of genes, pathways and networks involved in disease severity and age at onset in primary-progressive multiple sclerosis. Mult Scler 2015; 21:1431-42. [DOI: 10.1177/1352458514564590] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2014] [Accepted: 11/15/2014] [Indexed: 01/12/2023]
Abstract
Background: The role of genetic factors in influencing the clinical expression of multiple sclerosis (MS) is unclear. Objective: The objective of this paper is to identify genes, pathways and networks implicated in age at onset (AAO) and severity, measured using the Multiple Sclerosis Severity Score (MSSS), of primary-progressive MS (PPMS). Methods: We conducted a genome-wide association study (GWAS) of 470 PPMS patients of Italian origin:. Allelic association of 296,589 SNPs with AAO and MSSS was calculated. Pathway and network analyses were also conducted using different tools. Results: No single association signal exceeded genome-wide significance in AAO and MSSS analyses. Nominally associated genes to AAO and MSSS were enriched in both traits for 10 pathways, including: “oxidative phosphorylation” (FDRAAO=9*10−4; FDRMSSS=3.0*10−2), “citrate (TCA) cycle” (FDRAAO=1.6*10−2; FDRMSSS=3.2*10−3), and “B cell receptor signaling” (FDRAAO=3.1*10−2; FDRMSSS=2.2*10−3). In addition, an enrichment of “chemokine signaling pathway” (FDR=9*10−4) for AAO and of “leukocyte transendothelial migration” (FDR=2.4*10−3) for MSSS trait was observed, among others. Network analysis revealed that p53 and CREB1 were central hubs for AAO and MSSS traits, respectively. Conclusions: Despite the fact that no major effect signals emerged in the present GWAS, our data suggest that genetic variants acting in the context of oxidative stress and immune dysfunction could modulate the onset and severity of PPMS.
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Affiliation(s)
- G Giacalone
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - F Clarelli
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - AM Osiceanu
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - C Guaschino
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - P Brambilla
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - M Sorosina
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - G Liberatore
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - A Zauli
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - F Esposito
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - M Rodegher
- Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - A Ghezzi
- Department of Neurology, S. Antonio Abate Hospital, Gallarate, Italy
| | - D Galimberti
- Neurology Unit, Department of Pathophysiology and Transplantation, University of Milan, Fondazione Cà Granda, IRCCS Ospedale Policlinico, Milan, Italy
| | - F Patti
- Department DANA, G.F. Ingrassia, Neurosciences Section, Multiple Sclerosis Center, PO “G. Rodolico,” Catania, Italy
| | - N Barizzone
- Department of Health Sciences, “A. Avogadro” University of Eastern Piedmont, Novara, Italy
| | - F Guerini
- Don C. Gnocchi Foundation ONLUS, IRCCS, 20100 Milan, Italy
| | - V Martinelli
- Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - M Leone
- Department of Health Sciences, “A. Avogadro” University of Eastern Piedmont, Novara, Italy/ SCDU Neurologia, “A. Avogadro” University of Eastern Piedmont and AOU “Maggiore della Carità”, Novara, Italy; IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), “A. Avogadro” University of Piemonte Orientale, Novara, Italy
| | - G Comi
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
| | - S D’Alfonso
- Department of Health Sciences, “A. Avogadro” University of Eastern Piedmont, Novara, Italy/ SCDU Neurologia, “A. Avogadro” University of Eastern Piedmont and AOU “Maggiore della Carità”, Novara, Italy; IRCAD (Interdisciplinary Research Center of Autoimmune Diseases), “A. Avogadro” University of Piemonte Orientale, Novara, Italy
| | - F Martinelli Boneschi
- Laboratory of Genetics of Neurological Complex Disorders, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy/ Department of Neurology, Institute of Experimental Neurology (INSPE), Division of Neuroscience, San Raffaele Scientific Institute, Italy
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N-glycosylation bidirectionally extends the boundaries of thymocyte positive selection by decoupling Lck from Ca²⁺ signaling. Nat Immunol 2014; 15:1038-45. [PMID: 25263124 DOI: 10.1038/ni.3007] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2014] [Accepted: 09/09/2014] [Indexed: 12/13/2022]
Abstract
Positive selection of diverse yet self-tolerant thymocytes is vital to immunity and requires a limited degree of T cell antigen receptor (TCR) signaling in response to self peptide-major histocompatibility complexes (self peptide-MHCs). Affinity of newly generated TCR for peptide-MHC primarily sets the boundaries for positive selection. We report that N-glycan branching of TCR and the CD4 and CD8 coreceptors separately altered the upper and lower affinity boundaries from which interactions between peptide-MHC and TCR positively select T cells. During thymocyte development, N-glycan branching varied approximately 15-fold. N-glycan branching was required for positive selection and decoupled Lck signaling from TCR-driven Ca(2+) flux to simultaneously promote low-affinity peptide-MHC responses while inhibiting high-affinity ones. Therefore, N-glycan branching imposes a sliding scale on interactions between peptide-MHC and TCR that bidirectionally expands the affinity range for positive selection.
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Lill CM. Recent advances and future challenges in the genetics of multiple sclerosis. Front Neurol 2014; 5:130. [PMID: 25071715 PMCID: PMC4094909 DOI: 10.3389/fneur.2014.00130] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 07/01/2014] [Indexed: 01/22/2023] Open
Abstract
Multiple sclerosis (MS) is the most common auto-inflammatory disease of the central nervous system, affecting more than 2 million individuals worldwide. It is a genetically complex disease, in which a substantial part of a person’s liability to develop MS is caused by a combination of multiple genetic and non-genetic (e.g., environmental) risk factors. Increasing this complexity, many of the involved risk factors likely interact in an intricate and hitherto ill-defined fashion. Despite these complexities, and owing greatly to the advent and application of large-scale genome-wide association studies, our understanding of the genetic factors underlying MS etiology has begun to gain unprecedented momentum. In this perspective, I will summarize some recent advances and outline future challenges in MS genetics research.
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Affiliation(s)
- Christina M Lill
- Neuropsychiatric Genetics Group, Department of Vertebrate Genomics, Max Planck Institute for Molecular Genetics , Berlin , Germany ; Focus Program Translational Neuroscience, Department of Neurology, University Medical Center of the Johannes Gutenberg University Mainz , Mainz , Germany
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Goulabchand R, Vincent T, Batteux F, Eliaou JF, Guilpain P. Impact of autoantibody glycosylation in autoimmune diseases. Autoimmun Rev 2014; 13:742-50. [DOI: 10.1016/j.autrev.2014.02.005] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Accepted: 02/01/2014] [Indexed: 12/12/2022]
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García-Vallejo JJ, Ilarregui JM, Kalay H, Chamorro S, Koning N, Unger WW, Ambrosini M, Montserrat V, Fernandes RJ, Bruijns SCM, van Weering JRT, Paauw NJ, O'Toole T, van Horssen J, van der Valk P, Nazmi K, Bolscher JGM, Bajramovic J, Dijkstra CD, 't Hart BA, van Kooyk Y. CNS myelin induces regulatory functions of DC-SIGN-expressing, antigen-presenting cells via cognate interaction with MOG. ACTA ACUST UNITED AC 2014; 211:1465-83. [PMID: 24935259 PMCID: PMC4076586 DOI: 10.1084/jem.20122192] [Citation(s) in RCA: 77] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Human myelin oligodendrocyte glycoprotein is decorated with fucosylated N-glycans that are recognized by DC-SIGN+ DCs and microglia that control immune homeostasis. Myelin oligodendrocyte glycoprotein (MOG), a constituent of central nervous system myelin, is an important autoantigen in the neuroinflammatory disease multiple sclerosis (MS). However, its function remains unknown. Here, we show that, in healthy human myelin, MOG is decorated with fucosylated N-glycans that support recognition by the C-type lectin receptor (CLR) DC-specific intercellular adhesion molecule-3–grabbing nonintegrin (DC-SIGN) on microglia and DCs. The interaction of MOG with DC-SIGN in the context of simultaneous TLR4 activation resulted in enhanced IL-10 secretion and decreased T cell proliferation in a DC-SIGN-, glycosylation-, and Raf1-dependent manner. Exposure of oligodendrocytes to proinflammatory factors resulted in the down-regulation of fucosyltransferase expression, reflected by altered glycosylation at the MS lesion site. Indeed, removal of fucose on myelin reduced DC-SIGN–dependent homeostatic control, and resulted in inflammasome activation, increased T cell proliferation, and differentiation toward a Th17-prone phenotype. These data demonstrate a new role for myelin glycosylation in the control of immune homeostasis in the healthy human brain through the MOG–DC-SIGN homeostatic regulatory axis, which is comprised by inflammatory insults that affect glycosylation. This phenomenon should be considered as a basis to restore immune tolerance in MS.
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Affiliation(s)
- J J García-Vallejo
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - J M Ilarregui
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - H Kalay
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - S Chamorro
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - N Koning
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - W W Unger
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - M Ambrosini
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - V Montserrat
- Division of Cell Biology, Dutch Cancer Institute, 1066X Amsterdam, Netherlands
| | - R J Fernandes
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - S C M Bruijns
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - J R T van Weering
- Department of Functional Genomics and Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam; and Department of Pathology, VU University Amsterdam, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - N J Paauw
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - T O'Toole
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - J van Horssen
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands Department of Functional Genomics and Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam; and Department of Pathology, VU University Amsterdam, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - P van der Valk
- Department of Functional Genomics and Clinical Genetics, Center for Neurogenomics and Cognitive Research, Neuroscience Campus Amsterdam; and Department of Pathology, VU University Amsterdam, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - K Nazmi
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam, VU University, 1081LA Amsterdam, Netherlands
| | - J G M Bolscher
- Department of Oral Biochemistry, Academic Centre for Dentistry Amsterdam, University of Amsterdam, VU University, 1081LA Amsterdam, Netherlands
| | - J Bajramovic
- Alternatives Unit and Dept. Immunobiology, Biomedical Primate Research Centre, 2280 GH Rijswijk, Netherlands
| | - C D Dijkstra
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
| | - B A 't Hart
- Alternatives Unit and Dept. Immunobiology, Biomedical Primate Research Centre, 2280 GH Rijswijk, Netherlands Department Neuroscience, University Medical Center, University of Groningen, 9713GZ Groningen, Netherlands
| | - Y van Kooyk
- Department of Molecular Cell Biology and Immunology, VU University Medical Center, 1081HV Amsterdam, Netherlands
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Abstract
Genome-wide association studies have revolutionised the genetic analysis of multiple sclerosis. Through international collaborative efforts involving tens of thousands of cases and controls, more than 100 associated common variants have now been identified. These variants consistently implicate genes associated with immunological processes, overwhelmingly lie in regulatory rather than coding regions, and are frequently associated with other autoimmune diseases. The functional implications of these associated variants are mostly unknown; however, early work has shown that several variants have effects on splicing that result in meaningful changes in the balance between different isoforms in relevant tissues. Including the well established risk attributable to variants in genes encoding human leucocyte antigens, only about a quarter of reported heritability can now be accounted for, suggesting that a substantial potential for further discovery remains.
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Affiliation(s)
- Stephen Sawcer
- Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK.
| | - Robin J M Franklin
- Wellcome Trust-Medical Research Council Cambridge Stem Cell Institute, University of Cambridge, Cambridge, UK; Department of Veterinary Medicine, University of Cambridge, Cambridge, UK
| | - Maria Ban
- Department of Clinical Neurosciences, Cambridge Biomedical Campus, University of Cambridge, Cambridge, UK
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39
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Schattling B, Eggert B, Friese MA. Acquired channelopathies as contributors to development and progression of multiple sclerosis. Exp Neurol 2014; 262 Pt A:28-36. [PMID: 24656770 DOI: 10.1016/j.expneurol.2013.12.006] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Accepted: 12/13/2013] [Indexed: 12/18/2022]
Abstract
Multiple sclerosis (MS), the most frequent inflammatory disease of the central nervous system (CNS), affects about two and a half million individuals worldwide and causes major burdens to the patients, which develop the disease usually at the age of 20 to 40. MS is likely referable to a breakdown of immune cell tolerance to CNS self-antigens resulting in focal immune cell infiltration, activation of microglia and astrocytes, demyelination and axonal and neuronal loss. Here we discuss how altered expression patterns and dysregulated functions of ion channels contribute on a molecular level to nearly all pathophysiological steps of the disease. In particular the detrimental redistribution of ion channels along axons, as well as neuronal excitotoxicity with regard to imbalanced glutamate homeostasis during chronic CNS inflammation will be discussed in detail. Together, we describe which ion channels in the immune and nervous system commend as attractive future drugable targets in MS treatment.
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Affiliation(s)
- Benjamin Schattling
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, D-20251 Hamburg, Germany
| | - Britta Eggert
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, D-20251 Hamburg, Germany
| | - Manuel A Friese
- Zentrum für Molekulare Neurobiologie, Universitätsklinikum Hamburg-Eppendorf, Falkenried 94, D-20251 Hamburg, Germany.
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40
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Abstract
Multiple sclerosis (MS) is the most frequent chronic inflammatory disease of the CNS, and imposes major burdens on young lives. Great progress has been made in understanding and moderating the acute inflammatory components of MS, but the pathophysiological mechanisms of the concomitant neurodegeneration--which causes irreversible disability--are still not understood. Chronic inflammatory processes that continuously disturb neuroaxonal homeostasis drive neurodegeneration, so the clinical outcome probably depends on the balance of stressor load (inflammation) and any remaining capacity for neuronal self-protection. Hence, suitable drugs that promote the latter state are sorely needed. With the aim of identifying potential novel therapeutic targets in MS, we review research on the pathological mechanisms of neuroaxonal dysfunction and injury, such as altered ion channel activity, and the endogenous neuroprotective pathways that counteract oxidative stress and mitochondrial dysfunction. We focus on mechanisms inherent to neurons and their axons, which are separable from those acting on inflammatory responses and might, therefore, represent bona fide neuroprotective drug targets with the capability to halt MS progression.
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41
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Abstract
Multiple sclerosis (MS) patients are classified as either having relapsing onset or progressive onset disease, also known as primary progressive MS (PPMS). Relative to relapsing onset patients, PPMS patients are older at disease onset, are equally likely to be men or women, and have more rapid accumulation of disability that does not respond well to treatments used in relapsing onset MS. Although estimates vary, 5-15% of all MS patients have a PPMS disease course. Genetic variance is a proposed determinant of MS disease course. If distinct genes associated with PPMS were identified study of these genes might lead to an understanding of the biology underlying disease progression and neural degeneration that are the hallmarks of PPMS. These genes and their biological pathways might also represent therapeutic targets. This chapter systematically reviews the PPMS genetic literature. Despite the intuitively appealing notion that differences between PPMS and relapsing onset MS are due to genetics, definite differences associated with these phenotypes at the major histocompatibility complex or elsewhere in the genome have not been found. Recent large-scale genome wide screens identified multiple genes associated with MS susceptibility outside the MHC. The genetic variants identified thus far make only weak individual contributions to MS susceptibility. If the genetic effects that contribute to the differences between PPMS and relapsing MS are similar in magnitude to those that distinguish MS from healthy controls then, given the relative scarcity of the PPMS phenotype, very large datasets will be needed to identify PPMS associated genes. International collaborative efforts could provide the means to identify such genes. Alternately, it is possible that factors other than genetics underlie the differences between these clinical phenotypes.
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Affiliation(s)
- Bruce A C Cree
- Department of Neurology, University of California, San Francisco, USA.
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42
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Dias AM, Dourado J, Lago P, Cabral J, Marcos-Pinto R, Salgueiro P, Almeida CR, Carvalho S, Fonseca S, Lima M, Vilanova M, Dinis-Ribeiro M, Reis CA, Pinho SS. Dysregulation of T cell receptor N-glycosylation: a molecular mechanism involved in ulcerative colitis. Hum Mol Genet 2013; 23:2416-27. [PMID: 24334766 DOI: 10.1093/hmg/ddt632] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
The incidence of inflammatory bowel disease is increasing worldwide and the underlying molecular mechanisms are far from being fully elucidated. Herein, we evaluated the role of N-glycosylation dysregulation in T cells as a key mechanism in the ulcerative colitis (UC) pathogenesis. The evaluation of the branched N-glycosylation levels and profile of intestinal T cell receptor (TCR) were assessed in colonic biopsies from UC patients and healthy controls. Expression alterations of the glycosyltransferase gene MGAT5 were also evaluated. We demonstrated that UC patients exhibit a dysregulation of TCR branched N-glycosylation on lamina propria T lymphocytes. Patients with severe UC showed the most pronounced defect on N-glycan branching in T cells. Moreover, UC patients showed a significant reduction of MGAT5 gene transcription in T lymphocytes. In this study, we disclose for the first time that a deficiency in branched N-glycosylation on TCR due to a reduced MGAT5 gene expression is a new molecular mechanism underlying UC pathogenesis, being a potential novel biomarker with promising clinical and therapeutic applications.
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Affiliation(s)
- Ana M Dias
- Institute of Molecular Pathology and Immunology of the University of Porto (IPATIMUP), Porto, Portugal
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43
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Glycosylation des autoanticorps au cours des maladies auto-immunes. Rev Med Interne 2013; 34:746-53. [DOI: 10.1016/j.revmed.2013.09.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2013] [Revised: 07/01/2013] [Accepted: 09/14/2013] [Indexed: 01/13/2023]
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44
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Dennis JW, Brewer CF. Density-dependent lectin-glycan interactions as a paradigm for conditional regulation by posttranslational modifications. Mol Cell Proteomics 2013; 12:913-20. [PMID: 23378517 DOI: 10.1074/mcp.r112.026989] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Mice with null mutations in specific Golgi glycosyltransferases show evidence of glycan compensation where missing carbohydrate epitopes are found on biosynthetically related structures. Repetitive saccharide sequences within the larger glycan structures are functional epitopes recognized by animal lectins. These studies provide the first in vivo support for the existence of a feedback system that maintains and regulates glycan epitope density in cells. Receptor regulation by lectin-glycan interactions and the Golgi provides a mechanism for the adaptation of cell surface receptors and solute transporters in response to environmental cues and intracellular signaling. We suggest that other posttranslational modification systems might have similar conditional features regulated by density-dependent ligand-epitope interactions.
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Affiliation(s)
- James W Dennis
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, and Department of Molecular Genetics, University of Toronto, Toronto, Ontario, Canada
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45
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Li CF, Zhou RW, Mkhikian H, Newton BL, Yu Z, Demetriou M. Hypomorphic MGAT5 polymorphisms promote multiple sclerosis cooperatively with MGAT1 and interleukin-2 and 7 receptor variants. J Neuroimmunol 2013; 256:71-6. [PMID: 23351704 DOI: 10.1016/j.jneuroim.2012.12.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Revised: 12/13/2012] [Accepted: 12/17/2012] [Indexed: 01/27/2023]
Abstract
Deficiency of the Golgi N-glycan branching enzyme Mgat5 in mice promotes T cell hyperactivity, endocytosis of CTLA-4 and autoimmunity, including a spontaneous multiple sclerosis (MS)-like disease. Multiple genetic and environmental MS risk factors lower N-glycan branching in T cells. These include variants in interleukin-2 receptor-α (IL2RA), interleukin-7 receptor-α (IL7RA), and MGAT1, a Golgi branching enzyme upstream of MGAT5, as well as vitamin D3 deficiency and Golgi substrate metabolism. Here we describe linked intronic variants of MGAT5 that are associated with reduced N-glycan branching, CTLA-4 surface expression and MS (p=5.79×10(-9), n=7,741), the latter additive with the MGAT1, IL2RA and IL7RA MS risk variants (p=1.76×10(-9), OR=0.67-1.83, n=3,518).
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Affiliation(s)
- Carey F Li
- Department of Neurology, University of California, Irvine, CA 92869, USA
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46
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Yu Z, Gillen D, Li CF, Demetriou M. Incorporating parental information into family-based association tests. Biostatistics 2012; 14:556-72. [PMID: 23266418 DOI: 10.1093/biostatistics/kxs048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Assumptions regarding the true underlying genetic model, or mode of inheritance, are necessary when quantifying genetic associations with disease phenotypes. Here we propose new methods to ascertain the underlying genetic model from parental data in family-based association studies. Specifically, for parental mating-type data, we propose a novel statistic to test whether the underlying genetic model is additive, dominant, or recessive; for parental genotype-phenotype data, we propose three strategies to determine the true mode of inheritance. We illustrate how to incorporate the information gleaned from these strategies into family-based association tests. Because family-based association tests are conducted conditional on parental genotypes, the type I error rate of these procedures is not inflated by the information learned from parental data. This result holds even if such information is weak or when the assumption of Hardy-Weinberg equilibrium is violated. Our simulations demonstrate that incorporating parental data into family-based association tests can improve power under common inheritance models. The application of our proposed methods to a candidate-gene study of type 1 diabetes successfully detects a recessive effect in MGAT5 that would otherwise be missed by conventional family-based association tests.
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Affiliation(s)
- Zhaoxia Yu
- Department of Statistics, University of California at Irvine, Irvine, CA 92697, USA.
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47
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McElroy JP, Krupp LB, Johnson BA, McCauley JL, Qi Z, Caillier SJ, Gourraud PA, Yu J, Nathanson L, Belman AL, Hauser SL, Waubant E, Hedges DJ, Oksenberg JR. Copy number variation in pediatric multiple sclerosis. Mult Scler 2012; 19:1014-21. [PMID: 23239789 DOI: 10.1177/1352458512469696] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Pediatric onset multiple sclerosis (MS) accounts for 2-4% of all MS. It is unknown whether the disease shares the same underlying pathophysiology found in adult patients or an extreme early onset phenotype triggered by distinct biological mechanisms. It has been hypothesized that copy number variations (CNVs) may result in extreme early onset diseases because CNVs can have major effects on many genes in large genomic regions. OBJECTIVES AND METHODS The objective of the current research was to identify CNVs, with a specific focus on de novo CNVs, potentially causing early onset MS by competitively hybridizing 30 white non-Hispanic pediatric MS patients with each of their parents via comparative genomic hybridization (CGH) analysis on the Agilent 1M CGH array. RESULTS AND DISCUSSION We identified 10 CNVs not overlapping with any CNV regions currently reported in the Database of Genomic Variants (DGV). Fifty-five putatively de novo CNVs were also identified: all but one common in the DGV. We found the single rare CNV was a private variation harboring the SACS gene. SACS mutations cause autosomal-recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) disease. Additional clinical review revealed that the patient with the SACS gene CNV shared some features of both MS and ARSACS. CONCLUSIONS This is the first reported study analyzing pediatric MS CNVs. While not yielding causal variation in our initial pediatric dataset, our approach confirmed diagnosis of an ARSACS-like disease in addition to MS in the affected individual, which led to a more complete understanding of the patient's disease course and prognosis.
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Affiliation(s)
- J P McElroy
- Department of Neurology, University of California at San Francisco, USA.
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48
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Orr SL, Le D, Long JM, Sobieszczuk P, Ma B, Tian H, Fang X, Paulson JC, Marth JD, Varki N. A phenotype survey of 36 mutant mouse strains with gene-targeted defects in glycosyltransferases or glycan-binding proteins. Glycobiology 2012; 23:363-80. [PMID: 23118208 DOI: 10.1093/glycob/cws150] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
The consortium for functional glycomics (CFG) was a large research initiative providing networking and resources for investigators studying the role of glycans and glycan-binding proteins in health and disease. Starting in 2001, six scientific cores were established to generate data, materials and new technologies. By the end of funding in 2011, the mouse phenotype core (MPC) submitted data to a website from the phenotype screen of 36 mutant mouse strains deficient in a gene for either a glycan-binding protein (GBP) or glycosyltransferase (GT). Each mutant strain was allotted three months for analysis and screened by standard phenotype assays used in the fields of immunology, histology, hematology, coagulation, serum chemistry, metabolism and behavior. Twenty of the deficient mouse strains had been studied in other laboratories, and additional tests were performed on these strains to confirm previous observations and discover new data. The CFG constructed 16 new homozygous mutant mouse strains and completed the initial phenotype screen of the majority of these new mutant strains. In total, >300 phenotype changes were observed, but considering the over 100 assays performed on each strain, most of the phenotypes were unchanged. Phenotype differences include abnormal testis morphology in GlcNAcT9- and Siglec-H-deficient mice and lethality in Pomgnt1-deficient mice. The numerous altered phenotypes discovered, along with the consideration of the significant findings of normality, will provide a platform for future characterization to understand the important roles of glycans and GBPs in the mechanisms of health and disease.
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Affiliation(s)
- Sally L Orr
- Department of Pathology, University of California, San Diego, La Jolla, CA 92093-0687, USA
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49
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Zoldoš V, Novokmet M, Bečeheli I, Lauc G. Genomics and epigenomics of the human glycome. Glycoconj J 2012; 30:41-50. [PMID: 22648057 DOI: 10.1007/s10719-012-9397-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2012] [Revised: 05/11/2012] [Accepted: 05/14/2012] [Indexed: 12/17/2022]
Abstract
The majority of all proteins are glycosylated and glycans have numerous important structural, functional and regulatory roles in various physiological processes. While structure of the polypeptide part of a glycoprotein is defined by the sequence of nucleotides in the corresponding gene, structure of a glycan part results from dynamic interactions between hundreds of genes, their protein products and environmental factors. The composition of the glycome attached to an individual protein, or to a complex mixture of proteins, like human plasma, is stable within an individual, but very variable between individuals. This variability stems from numerous common genetic polymorphisms reflecting in changes in the complex biosynthetic pathway of glycans, but also from the interaction with the environment. Environment can affect glycan biosynthesis at the level of substrate availability, regulation of enzyme activity and/or hormonal signals, but also through gene-environment interactions. Epigenetics provides a molecular basis how the environment can modify phenotype of an individual. The epigenetic information (DNA methylation pattern and histone code) is especially vulnerable to environmental effects in the early intrauterine and neo-natal development and many common late-onset diseases take root already at that time. The evidences showing the link between epigenetics and glycosylation are accumulating. Recent progress in high-throughput glycomics, genomics and epigenomics enabled first epidemiological and genome-wide association studies of the glycome, which are presented in this mini-review.
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Affiliation(s)
- Vlatka Zoldoš
- University of Zagreb, Faculty of Science, Horvatovac 102a, Zagreb, Croatia.
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50
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De Jager PL. Genome-wide association study of severity in multiple sclerosis. Genes Immun 2011; 12:615-25. [PMID: 21654844 PMCID: PMC3640650 DOI: 10.1038/gene.2011.34] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Accepted: 04/11/2011] [Indexed: 01/20/2023]
Abstract
Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system with a strong genetic component. Several lines of evidence support a strong role for genetic factors influencing both disease susceptibility and clinical outcome in MS. Identification of genetic variants that distinguish particular disease subgroups and/or predict a severe clinical outcome is critical to further our understanding of disease mechanisms and guide development of effective therapeutic approaches. We studied 1470 MS cases and performed a genome-wide association study of more than 2.5 million single-nucleotide polymorphisms to identify loci influencing disease severity, measured using the MS severity score (MSSS), a measure of clinical disability. Of note, no single result achieved genome-wide significance. Furthermore, variants within previously confirmed MS susceptibility loci do not appear to influence severity. Although bioinformatic analyses highlight certain pathways that are over-represented in our results, we conclude that the genetic architecture of disease severity is likely polygenic and comprised of modest effects, similar to what has been described for MS susceptibility, to date. However, a role for major effects of rare variants cannot be excluded. Importantly, our results also show the MSSS, when considered as a binary or continuous phenotype variable is by comparison a stable outcome.
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Affiliation(s)
- PL De Jager
- Program in Translational NeuroPsychiatric Genomics, Department of Neurology, Brigham & Women’s Hospital and Harvard Medical School, and Program in Medical & Population Genetics, Broad Institute of Harvard University and Massachusetts Institute of Technology, Cambridge, MA 02139, USA
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