24 results on '"Nagra RM"'
Search Results
2. Rapidly progressive demyelinating lesions in three young adults - can this be due to an overreactivation of HHV-6?
- Author
-
Nakawatase, TV, primary, Novoa, LJ, additional, Nagra, RM, additional, Tourtellotte, WW, additional, and Cornford, ME, additional
- Published
- 1997
- Full Text
- View/download PDF
3. Networking of multiple sclerosis tissue banks.
- Author
-
Dole K, Nagra RM, Lipton H, Valyi-Nagy T, Corti M, Kleinschmidt-Demasters BK, Kennedy PM, and Bowling AC
- Published
- 2008
4. Getting the word out.
- Author
-
Nagra RM
- Published
- 2008
5. MAPT H2 haplotype and risk of Pick's disease in the Pick's disease International Consortium: a genetic association study.
- Author
-
Valentino RR, Scotton WJ, Roemer SF, Lashley T, Heckman MG, Shoai M, Martinez-Carrasco A, Tamvaka N, Walton RL, Baker MC, Macpherson HL, Real R, Soto-Beasley AI, Mok K, Revesz T, Christopher EA, DeTure M, Seeley WW, Lee EB, Frosch MP, Molina-Porcel L, Gefen T, Redding-Ochoa J, Ghetti B, Robinson AC, Kobylecki C, Rowe JB, Beach TG, Teich AF, Keith JL, Bodi I, Halliday GM, Gearing M, Arzberger T, Morris CM, White CL 3rd, Mechawar N, Boluda S, MacKenzie IR, McLean C, Cykowski MD, Wang SJ, Graff C, Nagra RM, Kovacs GG, Giaccone G, Neumann M, Ang LC, Carvalho A, Morris HR, Rademakers R, Hardy JA, Dickson DW, Rohrer JD, and Ross OA
- Subjects
- Female, Humans, Male, Genetic Association Studies, Haplotypes, tau Proteins genetics, Pick Disease of the Brain genetics, Tauopathies
- Abstract
Background: Pick's disease is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. Pick's disease is pathologically defined by the presence in the frontal and temporal lobes of Pick bodies, composed of hyperphosphorylated, three-repeat tau protein, encoded by the MAPT gene. MAPT has two distinct haplotypes, H1 and H2; the MAPT H1 haplotype is the major genetic risk factor for four-repeat tauopathies (eg, progressive supranuclear palsy and corticobasal degeneration), and the MAPT H2 haplotype is protective for these disorders. The primary aim of this study was to evaluate the association of MAPT H2 with Pick's disease risk, age at onset, and disease duration., Methods: In this genetic association study, we used data from the Pick's disease International Consortium, which we established to enable collection of data from individuals with pathologically confirmed Pick's disease worldwide. For this analysis, we collected brain samples from individuals with pathologically confirmed Pick's disease from 35 sites (brainbanks and hospitals) in North America, Europe, and Australia between Jan 1, 2020, and Jan 31, 2023. Neurologically healthy controls were recruited from the Mayo Clinic (FL, USA, or MN, USA between March 1, 1998, and Sept 1, 2019). For the primary analysis, individuals were directly genotyped for the MAPT H1-H2 haplotype-defining variant rs8070723. In a secondary analysis, we genotyped and constructed the six-variant-defined (rs1467967-rs242557-rs3785883-rs2471738-rs8070723-rs7521) MAPT H1 subhaplotypes. Associations of MAPT variants and MAPT haplotypes with Pick's disease risk, age at onset, and disease duration were examined using logistic and linear regression models; odds ratios (ORs) and β coefficients were estimated and correspond to each additional minor allele or each additional copy of the given haplotype., Findings: We obtained brain samples from 338 people with pathologically confirmed Pick's disease (205 [61%] male and 133 [39%] female; 338 [100%] White) and 1312 neurologically healthy controls (611 [47%] male and 701 [53%] female; 1312 [100%] White). The MAPT H2 haplotype was associated with increased risk of Pick's disease compared with the H1 haplotype (OR 1·35 [95% CI 1·12 to 1·64], p=0·0021). MAPT H2 was not associated with age at onset (β -0·54 [95% CI -1·94 to 0·87], p=0·45) or disease duration (β 0·05 [-0·06 to 0·16], p=0·35). Although not significant after correcting for multiple testing, associations were observed at p less than 0·05: with risk of Pick's disease for the H1f subhaplotype (OR 0·11 [0·01 to 0·99], p=0·049); with age at onset for H1b (β 2·66 [0·63 to 4·70], p=0·011), H1i (β -3·66 [-6·83 to -0·48], p=0·025), and H1u (β -5·25 [-10·42 to -0·07], p=0·048); and with disease duration for H1x (β -0·57 [-1·07 to -0·07], p=0·026)., Interpretation: The Pick's disease International Consortium provides an opportunity to do large studies to enhance our understanding of the pathobiology of Pick's disease. This study shows that, in contrast to the decreased risk of four-repeat tauopathies, the MAPT H2 haplotype is associated with an increased risk of Pick's disease in people of European ancestry. This finding could inform development of isoform-related therapeutics for tauopathies., Funding: Wellcome Trust, Rotha Abraham Trust, Brain Research UK, the Dolby Fund, Dementia Research Institute (Medical Research Council), US National Institutes of Health, and the Mayo Clinic Foundation., Competing Interests: Declarations of interest WJS declares funding from a Wellcome Trust Clinical PhD Fellowship (220582/Z/20/Z) and from the Rotha Abraham Trust; and has received conference travel funding from the Guarantors of Brain. NT declares funding from the 2023 Diana Jacobs Kalman-American Federation for Aging Research Scholarship for Pre-Doctoral Research on the biology of aging. KM declares funding from the Michael J Fox Foundation, Innovation and Technology Commission, Hong Kong Government, and the Chow Tai Fook Charity Foundation; affiliations with the Hong Kong University of Science and Technology and University College London; employment with the Hong Kong Center for Neurodegenerative Diseases; and support for speaker and educational activity from the National Taiwan University, Yonsei University, and the Movement Disorder Society. WWS declares funding from the National Institutes of Health (NIH), Tau Consortium, Bluefield Project to Cure Frontotemporal Dementia, and the Chan-Zuckerberg Initiative. EBL declares funding from the NIH and personal honorarium from University of Toronto, Mayo Clinic, St Louis University, Haverford, University of Oslo, NIH, and the Association of Frontotemporal Dementia. LM-P declares personal honorarium from the Galician Society of Neurology and the Spanish Society of Neurology. JBR declares funding from the NIH Research Biomedical Research Centre, the Medical Research Council, Wellcome Trust, Cambridge Centre for Parkinson-plus, PSP association, and Alzheimer's UK; and has received consulting fees from Asceneuron, Astronautx, Astex, Curasen, CumulusNeuro, Wave, Prevail, and SVHealth. TGB declares funding from the NIH, Michael J Fox Foundation, and Life Molecular Imaging; personal consulting fees from Aprinoia Therapeutics; and stock options in Vivid Genomics. S-HJW declares funding from NIH and personal honorarium from the American Society of Clinical Pathology. CG declares funding from the Swedish Frontotemporal Dementia Inititative-Schörling Foundation, EU Joint Programme-Neurodegenerative Disease Research-Prefrontals, EU Joint Programme-Neurodegenerative Disease Research-Genetic Frontotemporal Dementia Initiative-Proximity, the Alzheimer Foundation, Brain Foundation, Dementia Foundation, Region Karolinska Institutet-StratNeuro Strategiska forskningsområden, Centre for Innovative Medicine, and Karolinska Institutet-Region Stockholm Core facility; personal honoraria from Demensdagarna Örebro, Diakonia Ersta sjukhus, and Göteborgsregionen. GGK declares funding from Edmond J Safra Philanthropic Foundation, Michael J Fox Foundation, Parkinson Canada, Canada, Canada Foundation for Innovation, MSA Coalition, and the NIH; and royalties from a patent for 5G4 synuclein antibody (DE102011008153B4); and personal honoraria from the Movement Disorders Society. MN declares funding from Deutsche Forschungsgemeinschaft and Alzheimer Forschungsinitiative. HRM declares funding from the PSP Association, CBD Solutions, the Drake Foundation, the Cure Parkinson's Trust, the Michael J Fox Foundation, and Parkinson's UK; consulting fees from Roche, Amylyx, and Aprinoia; personal honoraria from Kyowa-Kirin, BMJ, and the Movement Disorders Society; travel support from the Michael J Fox Foundation; is a co-applicant on a patent application related to C9ORF72 method for diagnosing a neurodegenerative disease (PCT/GB2012/052140); and serves on the Cure PSP Association Advisory Board, the Association of British Neurologists Movement Disorders Special Interest Group, and the Association of British Neurologists Neurogenetics Advisory Group. RRa declares consulting fees from Arkuda Therapeutics and is on the advisory board for the Kissick Family Foundation. JAH declares funding from the Dolby Charities, and consulting fees from Eli Lilly and Eisai. JDR declares funding from the Bluefied project and the Alzheimer's Associaton; and consulting fees from Novartis, Wave Life Sciences, Prevail, Alector, Aviado Bio, Takeda, Arkuda Therapeutics, and Denali Therapeutics. OAR declares internal funding from the Mayo Clinic Foundation. All other authors declare no competing interests., (Copyright © 2024 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.)
- Published
- 2024
- Full Text
- View/download PDF
6. TMEM106B Puncta Is Increased in Multiple Sclerosis Plaques, and Reduced Protein in Mice Results in Delayed Lipid Clearance Following CNS Injury.
- Author
-
Shafit-Zagardo B, Sidoli S, Goldman JE, DuBois JC, Corboy JR, Strittmatter SM, Guzik H, Edema U, Arackal AG, Botbol YM, Merheb E, Nagra RM, and Graff S
- Subjects
- Mice, Animals, Spinal Cord metabolism, Myelin-Oligodendrocyte Glycoprotein metabolism, Lipids adverse effects, Multiple Sclerosis, Encephalomyelitis, Autoimmune, Experimental
- Abstract
During inflammatory, demyelinating diseases such as multiple sclerosis (MS), inflammation and axonal damage are prevalent early in the course. Axonal damage includes swelling, defects in transport, and failure to clear damaged intracellular proteins, all of which affect recovery and compromise neuronal integrity. The clearance of damaged cell components is important to maintain normal turnover and restore homeostasis. In this study, we used mass spectrometry to identify insoluble proteins within high-speed/mercaptoethanol/sarcosyl-insoluble pellets from purified white matter plaques isolated from the brains of individuals with relapsing-remitting MS (RRMS). We determined that the transmembrane protein 106B (TMEM106B), normally lysosome-associated, is insoluble in RRMS plaques relative to normal-appearing white matter from individuals with Alzheimer's disease and non-neurologic controls. Relative to wild-type mice, hypomorphic mice with a reduction in TMEM106B have increased axonal damage and lipid droplet accumulation in the spinal cord following myelin-oligodendrocyte-glycoprotein-induced experimental autoimmune encephalomyelitis. Additionally, the corpora callosa from cuprizone-challenged hypomorphic mice fail to clear lipid droplets efficiently during remyelination, suggesting that when TMEM106B is compromised, protein and lipid clearance by the lysosome is delayed. As TMEM106B contains putative lipid- and LC3-binding sites, further exploration of these sites is warranted.
- Published
- 2023
- Full Text
- View/download PDF
7. Creating the Pick's disease International Consortium: Association study of MAPT H2 haplotype with risk of Pick's disease.
- Author
-
Valentino RR, Scotton WJ, Roemer SF, Lashley T, Heckman MG, Shoai M, Martinez-Carrasco A, Tamvaka N, Walton RL, Baker MC, Macpherson HL, Real R, Soto-Beasley AI, Mok K, Revesz T, Warner TT, Jaunmuktane Z, Boeve BF, Christopher EA, DeTure M, Duara R, Graff-Radford NR, Josephs KA, Knopman DS, Koga S, Murray ME, Lyons KE, Pahwa R, Parisi JE, Petersen RC, Whitwell J, Grinberg LT, Miller B, Schlereth A, Seeley WW, Spina S, Grossman M, Irwin DJ, Lee EB, Suh E, Trojanowski JQ, Van Deerlin VM, Wolk DA, Connors TR, Dooley PM, Frosch MP, Oakley DH, Aldecoa I, Balasa M, Gelpi E, Borrego-Écija S, de Eugenio Huélamo RM, Gascon-Bayarri J, Sánchez-Valle R, Sanz-Cartagena P, Piñol-Ripoll G, Molina-Porcel L, Bigio EH, Flanagan ME, Gefen T, Rogalski EJ, Weintraub S, Redding-Ochoa J, Chang K, Troncoso JC, Prokop S, Newell KL, Ghetti B, Jones M, Richardson A, Robinson AC, Roncaroli F, Snowden J, Allinson K, Green O, Rowe JB, Singh P, Beach TG, Serrano GE, Flowers XE, Goldman JE, Heaps AC, Leskinen SP, Teich AF, Black SE, Keith JL, Masellis M, Bodi I, King A, Sarraj SA, Troakes C, Halliday GM, Hodges JR, Kril JJ, Kwok JB, Piguet O, Gearing M, Arzberger T, Roeber S, Attems J, Morris CM, Thomas AJ, Evers BM, White CL, Mechawar N, Sieben AA, Cras PP, De Vil BB, De Deyn PPPP, Duyckaerts C, Le Ber I, Seihean D, Turbant-Leclere S, MacKenzie IR, McLean C, Cykowski MD, Ervin JF, Wang SJ, Graff C, Nennesmo I, Nagra RM, Riehl J, Kovacs GG, Giaccone G, Nacmias B, Neumann M, Ang LC, Finger EC, Blauwendraat C, Nalls MA, Singleton AB, Vitale D, Cunha C, Carvalho A, Wszolek ZK, Morris HR, Rademakers R, Hardy JA, Dickson DW, Rohrer JD, and Ross OA
- Abstract
Background: Pick's disease (PiD) is a rare and predominantly sporadic form of frontotemporal dementia that is classified as a primary tauopathy. PiD is pathologically defined by argyrophilic inclusion Pick bodies and ballooned neurons in the frontal and temporal brain lobes. PiD is characterised by the presence of Pick bodies which are formed from aggregated, hyperphosphorylated, 3-repeat tau proteins, encoded by the MAPT gene. The MAPT H2 haplotype has consistently been associated with a decreased disease risk of the 4-repeat tauopathies of progressive supranuclear palsy and corticobasal degeneration, however its role in susceptibility to PiD is unclear. The primary aim of this study was to evaluate the association between MAPT H2 and risk of PiD., Methods: We established the Pick's disease International Consortium (PIC) and collected 338 (60.7% male) pathologically confirmed PiD brains from 39 sites worldwide. 1,312 neurologically healthy clinical controls were recruited from Mayo Clinic Jacksonville, FL (N=881) or Rochester, MN (N=431). For the primary analysis, subjects were directly genotyped for MAPT H1-H2 haplotype-defining variant rs8070723. In secondary analysis, we genotyped and constructed the six-variant MAPT H1 subhaplotypes (rs1467967, rs242557, rs3785883, rs2471738, rs8070723, and rs7521)., Findings: Our primary analysis found that the MAPT H2 haplotype was associated with increased risk of PiD (OR: 1.35, 95% CI: 1.12-1.64 P=0.002). In secondary analysis involving H1 subhaplotypes, a protective association with PiD was observed for the H1f haplotype (0.0% vs. 1.2%, P=0.049), with a similar trend noted for H1b (OR: 0.76, 95% CI: 0.58-1.00, P=0.051). The 4-repeat tauopathy risk haplotype MAPT H1c was not associated with PiD susceptibility (OR: 0.93, 95% CI: 0.70-1.25, P=0.65)., Interpretation: The PIC represents the first opportunity to perform relatively large-scale studies to enhance our understanding of the pathobiology of PiD. This study demonstrates that in contrast to its protective role in 4R tauopathies, the MAPT H2 haplotype is associated with an increased risk of PiD. This finding is critical in directing isoform-related therapeutics for tauopathies., Competing Interests: M.A.N. and D.V.’s participation in this project was part of a competitive contract awarded to Data Tecnica International LLC by the National Institutes of Health to support open science research. M.A.N. also currently serves on the scientific advisory board for Character Bio Inc. and Neuron23 Inc.
- Published
- 2023
- Full Text
- View/download PDF
8. Evidence of increased sequestration of pro-resolving lipid mediators within brain esterified lipid pools of multiple sclerosis patients.
- Author
-
Shen Q, Otoki Y, Sobel RA, Nagra RM, and Taha AY
- Subjects
- Humans, Oxylipins analysis, Brain, Phospholipids, Epoxy Compounds, Tandem Mass Spectrometry methods, Multiple Sclerosis
- Abstract
Background: Unresolved inflammation in multiple sclerosis (MS) is associated with progressive demyelination and symptom worsening. In the brain, both inflammation and resolution pathways are mediated by free lipid mediators (i.e., oxylipins) that can be derived from the enzymatic hydrolysis of esterified oxylipins . It is not known whether disturbances in the turnover of free lipid mediators from esterified pools exist in postmortem brain of MS patients. We hypothesized that resolution pathways are impaired in MS patients because of disturbances in the turnover of free pro-resolving lipid mediators from esterified lipids. The objective was to characterize free and esterified oxylipins in postmortem prefrontal cortex of MS and unaffected control participants., Methods: Oxylipins in free, neutral lipid and phospholipid pools were extracted from prefrontal cortex of 10 MS participants and 5 unaffected controls, separated by solid phase extraction columns, and quantified by ultra-high-pressure liquid chromatography-tandem mass spectrometry. Significant differences between the control and MS groups were determined by an unpaired t-test with Benjamini and Hochberg False Discovery Rate correction (10%) applied to oxylipins within each lipid pool., Results: The concentration of 7 esterified pro-resolving fatty acid epoxides within neutral lipids were significantly higher by 126%-285% in postmortem prefrontal cortex of MS compared to control participants. The concentration of esterified linoleic acid-derived 9(10)-epoxy-octadecenoic acid, a pro-inflammatory epoxide, was higher by 206% in MS compared to controls. No significant changes were observed in free or phospholipid-bound oxylipins., Conclusion: In MS, several pro-resolving lipid mediators are trapped within prefrontal cortex neutral lipids, potentially limiting their supply and availability in the free bioactive form. This may explain why inflammation resolution is impaired in MS patients., Competing Interests: Declaration of Competing Interest The authors have no conflicts of interest to declare, (Copyright © 2022. Published by Elsevier B.V.)
- Published
- 2022
- Full Text
- View/download PDF
9. Development of Improved Double-Nanobody Sandwich ELISAs for Human Soluble Epoxide Hydrolase Detection in Peripheral Blood Mononuclear Cells of Diabetic Patients and the Prefrontal Cortex of Multiple Sclerosis Patients.
- Author
-
Li D, Morisseau C, McReynolds CB, Duflot T, Bellien J, Nagra RM, Taha AY, and Hammock BD
- Subjects
- Diabetes Mellitus enzymology, Epoxide Hydrolases metabolism, Humans, Leukocytes, Mononuclear pathology, Multiple Sclerosis enzymology, Diabetes Mellitus diagnosis, Enzyme-Linked Immunosorbent Assay, Epoxide Hydrolases analysis, Leukocytes, Mononuclear enzymology, Multiple Sclerosis diagnosis
- Abstract
Nanobodies have been progressively replacing traditional antibodies in various immunological methods. However, the use of nanobodies as capture antibodies is greatly hampered by their poor performance after passive adsorption to polystyrene microplates, and this restricts the full use of double nanobodies in sandwich enzyme-linked immunosorbent assays (ELISAs). Herein, using the human soluble epoxide hydrolase (sEH) as a model analyte, we found that both the immobilization format and the blocking agent have a significant influence on the performance of capture nanobodies immobilized on polystyrene and the subsequent development of double-nanobody sandwich ELISAs. We first conducted epitope mapping for pairing nanobodies and then prepared a horseradish-peroxidase-labeled nanobody using a mild conjugation procedure as a detection antibody throughout the work. The resulting sandwich ELISA using a capture nanobody (A9, 1.25 μg/mL) after passive adsorption and bovine serum albumin (BSA) as a blocking agent generated a moderate sensitivity of 0.0164 OD·mL/ng and a limit of detection (LOD) of 0.74 ng/mL. However, the introduction of streptavidin as a linker to the capture nanobody at the same working concentration demonstrated a dramatic 16-fold increase in sensitivity (0.262 OD·mL/ng) and a 25-fold decrease in the LOD for sEH (0.03 ng/mL). The streptavidin-bridged double-nanobody ELISA was then successfully applied to tests for recovery, cross-reactivity, and real samples. Meanwhile, we accidentally found that blocking with skim milk could severely damage the performance of the capture nanobody by an order of magnitude compared with BSA. This work provides guidelines to retain the high effectiveness of the capture nanobody and thus to further develop the double-nanobody ELISA for various analytes.
- Published
- 2020
- Full Text
- View/download PDF
10. B cells populating the multiple sclerosis brain mature in the draining cervical lymph nodes.
- Author
-
Stern JN, Yaari G, Vander Heiden JA, Church G, Donahue WF, Hintzen RQ, Huttner AJ, Laman JD, Nagra RM, Nylander A, Pitt D, Ramanan S, Siddiqui BA, Vigneault F, Kleinstein SH, Hafler DA, and O'Connor KC
- Subjects
- Adult, Aged, Aged, 80 and over, Antibodies immunology, Antigens metabolism, Cell Compartmentation, Cell Lineage, Cell Movement immunology, Clone Cells, Female, Humans, Male, Middle Aged, Models, Immunological, Sequence Analysis, Protein, B-Lymphocytes immunology, Brain pathology, Cell Differentiation immunology, Cervical Vertebrae pathology, Lymph Nodes pathology, Multiple Sclerosis immunology, Multiple Sclerosis pathology
- Abstract
Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by autoimmune-mediated demyelination and neurodegeneration. The CNS of patients with MS harbors expanded clones of antigen-experienced B cells that reside in distinct compartments including the meninges, cerebrospinal fluid (CSF), and parenchyma. It is not understood whether this immune infiltrate initiates its development in the CNS or in peripheral tissues. B cells in the CSF can exchange with those in peripheral blood, implying that CNS B cells may have access to lymphoid tissue that may be the specific compartment(s) in which CNS-resident B cells encounter antigen and experience affinity maturation. Paired tissues were used to determine whether the B cells that populate the CNS mature in the draining cervical lymph nodes (CLNs). High-throughput sequencing of the antibody repertoire demonstrated that clonally expanded B cells were present in both compartments. Founding members of clones were more often found in the draining CLNs. More mature clonal members derived from these founders were observed in the draining CLNs and also in the CNS, including lesions. These data provide new evidence that B cells traffic freely across the tissue barrier, with the majority of B cell maturation occurring outside of the CNS in the secondary lymphoid tissue. Our study may aid in further defining the mechanisms of immunomodulatory therapies that either deplete circulating B cells or affect the intrathecal B cell compartment by inhibiting lymphocyte transmigration into the CNS., (Copyright © 2014, American Association for the Advancement of Science.)
- Published
- 2014
- Full Text
- View/download PDF
11. Deep sequencing for the detection of virus-like sequences in the brains of patients with multiple sclerosis: detection of GBV-C in human brain.
- Author
-
Kriesel JD, Hobbs MR, Jones BB, Milash B, Nagra RM, and Fischer KF
- Subjects
- Adult, Aged, Aged, 80 and over, Brain pathology, Case-Control Studies, Cluster Analysis, GB virus C genetics, Genes, Viral, Humans, Middle Aged, Multiple Sclerosis diagnosis, Multiple Sclerosis etiology, RNA, Viral, Brain virology, Flaviviridae Infections complications, GB virus C isolation & purification, Hepatitis, Viral, Human complications, High-Throughput Nucleotide Sequencing, Multiple Sclerosis virology
- Abstract
Multiple sclerosis (MS) is a demyelinating disease of unknown origin that affects the central nervous system of an estimated 400,000 Americans. GBV-C or hepatitis G is a flavivirus that is found in the serum of 1-2% of blood donors. It was originally associated with hepatitis, but is now believed to be a relatively non-pathogenic lymphotropic virus. Fifty frozen specimens from the brains of deceased persons affected by MS were obtained along with 15 normal control brain specimens. RNA was extracted and ribosomal RNAs were depleted before sequencing on the Illumina GAII. These 36 bp reads were compared with a non-redundant database derived from the 600,000+ viral sequences in GenBank organized into 4080 taxa. An individual read successfully aligned to the viral database was considered to be a "hit". Normalized MS specimen hit rates for each viral taxon were compared to the distribution of hits in the normal controls. Seventeen MS and 11 control brain extracts were sequenced, yielding 4-10 million sequences ("reads") each. Over-representation of sequence from at least one of 12 viral taxa was observed in 7 of the 17 MS samples. Sequences resembling other viruses previously implicated in the pathogenesis of MS were not significantly enriched in any of the diseased brain specimens. Sequences from GB virus C (GBV-C), a flavivirus not previously isolated from brain, were enriched in one of the MS samples. GBV-C in this brain specimen was confirmed by specific amplification in this single MS brain specimen, but not in the 30 other MS brain samples available. The entire 9.4 kb sequence of this GBV-C isolate is reported here. This study shows the feasibility of deep sequencing for the detection of occult viral infections in the brains of deceased persons with MS. The first isolation of GBV-C from human brain is reported here.
- Published
- 2012
- Full Text
- View/download PDF
12. Preliminary demonstration of an allelic association of the IREB2 gene with Alzheimer's disease.
- Author
-
Coon KD, Siegel AM, Yee SJ, Dunckley TL, Mueller C, Nagra RM, Tourtellotte WW, Reiman EM, Papassotiropoulos A, Petersen FF, Stephan DA, and Kirsch WM
- Subjects
- Aged, Alleles, Alzheimer Disease psychology, Brain Chemistry genetics, Computer Simulation, DNA genetics, DNA isolation & purification, DNA Primers, Female, Gene Frequency, Genotype, Haplotypes, Humans, Male, Middle Aged, Phenotype, Pilot Projects, Polymorphism, Genetic genetics, Reverse Transcriptase Polymerase Chain Reaction, Alzheimer Disease genetics, Iron Regulatory Protein 2 genetics
- Abstract
The role of iron metabolism in Alzheimer's disease (AD) is well documented. Regulation of the proteins that maintain cellular iron metabolism is mediated by two cytoplasmic RNA-binding proteins, the Iron Regulatory Proteins (IRP1 and IRP2), that function through post-transcriptional interactions with RNA stem loop structures called iron-responsive elements. As the primary mediator of iron homeostasis in neuronal cells, IRP2 is a strong candidate for polymorphisms that could impact AD pathogenesis. Thus, we performed a pilot study to assess polymorphisms in the gene encoding IRP2 (IREB2) on clinically well-characterized, post-mortem samples (50 AD and 50 controls). DNA sequence analysis of the IREB2 gene region revealed 14 polymorphisms. Two (rs2656070 and rs13180) showed statistically significant skewing of allelic and genotypic distributions between AD patients and controls. In silico analyses revealed that rs2656070 lies within a probable promoter and disrupts the binding sites of at least two known transcription factors. Though silent and likely not functionally relevant, rs13180 is in complete LD with rs2656070 (D' > 0.999), creating an IREB2-haplotype that is significantly associated with AD. Confirmation of this association in a larger cohort of cases and controls would further support the role of iron regulation in the pathogenesis of this catastrophic and increasingly common neurodegenerative disorder.
- Published
- 2006
- Full Text
- View/download PDF
13. An examination of MS candidate genes identified as differentially regulated in multiple sclerosis plaque tissue, using absolute and comparative real-time Q-PCR analysis.
- Author
-
Tajouri L, Mellick AS, Tourtellotte A, Nagra RM, and Griffiths LR
- Subjects
- Female, Gene Dosage, Gene Expression Profiling standards, Gene Expression Regulation, Genetic Markers, Humans, Male, Middle Aged, Polymerase Chain Reaction standards, Postmortem Changes, Reproducibility of Results, Gene Expression Profiling methods, Multiple Sclerosis genetics, Multiple Sclerosis pathology, Polymerase Chain Reaction methods
- Abstract
In our laboratory, we have developed methods in real-time detection and quantitative-polymerase chain reaction (Q-PCR) to analyse the relative levels of gene expression in post mortem brain tissues. We have then applied this method to examine differences in gene activity between normal white matter (NWM) and plaque tissue from multiple sclerosis (MS) patients. Genes were selected based on their association with pathology and through identification by previously conducted global gene expression analysis. Plaque tissue was obtained from secondary progressive (SP) patients displaying chronic active, as well as acute pathologies; while NWM from the same location was obtained from age- and sex-matched controls (normal patients). In this study, we used both SYBR Green I supplementation and commercially available mixes to assess both comparative and absolute levels of gene activity. The results of both methods compared favourably for four of the five genes examined (P < 0.05, Pearsons), while differences in gene expression between chronic active and acute pathologies were also identified. For example, a >50-fold increase in osteopontin (Spp1) and inositol 1-4-5 phosphate 3 kinase B (Itpkb) levels in acute plaques contrasted with the 5-fold or less increase in chronic active plaques (P < 0.05, unpaired t test). By contrast, there was no significant difference in the levels of the MS marker and calcium-dependent protease (Calpain, Capns1) in MS plaque tissue. In summary, Q-PCR analysis using SYBR Green I has allowed us to economically obtain what may be clinically significant information from small amounts of the CNS, providing an opportunity for further clinical investigations.
- Published
- 2005
- Full Text
- View/download PDF
14. RANTES: a genetic risk marker for multiple sclerosis.
- Author
-
Gade-Andavolu R, Comings DE, MacMurray J, Vuthoori RK, Tourtellotte WW, Nagra RM, and Cone LA
- Subjects
- Adult, Aged, Female, Genetic Markers, Genetic Predisposition to Disease epidemiology, Genotype, Humans, Male, Middle Aged, Polymorphism, Genetic, Promoter Regions, Genetic, Risk Factors, Chemokine CCL5 genetics, Multiple Sclerosis epidemiology, Multiple Sclerosis genetics
- Abstract
Unlabelled: Regulated upon activation, normal T-cell expressed and secreted (RANTES) is a beta-chemokine and has been detected in brain lesions of multiple sclerosis (MS) patients. Considering its potential role in MS, we screened two functional polymorphisms in the proximal promoter region of the RANTES in MS patients versus controls., Methods: We examined 140 postmortem brain samples from subjects with a primary diagnosis of MS, and peripheral blood samples from 216 control subjects. The RANTES-28C/G and -403G/A promoter polymorphisms were examined. All subjects were non-Hispanic Caucasians., Results: MS cases differed from controls showing a significant association with the 403G/A polymorphism (odds ratio, 2.359, [1.465-3.799]; P=0.0001), but not the -28C/G (P=NS) polymorphism. There was a significant association of the -28G allele with both early onset (P=0.031) and longer survival (P=0.006)., Conclusion: There is a significant but complex association of the RANTES gene with MS.
- Published
- 2004
- Full Text
- View/download PDF
15. Quantitative and qualitative changes in gene expression patterns characterize the activity of plaques in multiple sclerosis.
- Author
-
Tajouri L, Mellick AS, Ashton KJ, Tannenberg AE, Nagra RM, Tourtellotte WW, and Griffiths LR
- Subjects
- Adult, Axons pathology, Central Nervous System pathology, Down-Regulation genetics, Female, Humans, Male, Multiple Sclerosis pathology, Nerve Tissue Proteins genetics, Oligonucleotide Array Sequence Analysis, RNA, Messenger analysis, RNA, Messenger genetics, Reproducibility of Results, Up-Regulation genetics, Axons metabolism, Central Nervous System metabolism, Gene Expression Regulation genetics, Multiple Sclerosis genetics, Multiple Sclerosis metabolism, Nerve Tissue Proteins metabolism
- Abstract
Multiple sclerosis (MS) is a complex autoimmune disorder of the CNS with both genetic and environmental contributing factors. Clinical symptoms are broadly characterized by initial onset, and progressive debilitating neurological impairment. In this study, RNA from MS chronic active and MS acute lesions was extracted, and compared with patient matched normal white matter by fluorescent cDNA microarray hybridization analysis. This resulted in the identification of 139 genes that were differentially regulated in MS plaque tissue compared to normal tissue. Of these, 69 genes showed a common pattern of expression in the chronic active and acute plaque tissues investigated (Pvalue<0.0001, rho=0.73, by Spearman's rho analysis); while 70 transcripts were uniquely differentially expressed (> or = 1.5-fold) in either acute or chronic active tissues. These results included known markers of MS such as the myelin basic protein (MBP) and glutathione S-transferase (GST) M1, nerve growth factors, such as nerve injury-induced protein 1 (NINJ1), X-ray and excision DNA repair factors (XRCC9 and ERCC5) and X-linked genes such as the ribosomal protein, RPS4X. Primers were then designed for seven array-selected genes, including transferrin (TF), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), GSTP1, crystallin, alpha-B (CRYAB), phosphomannomutase 1 (PMM1) and tubulin beta-5 (TBB5), and real time quantitative (Q)-PCR analysis was performed. The results of comparative Q-PCR analysis correlated significantly with those obtained by array analysis (r=0.75, Pvalue<0.01, by Pearson's bivariate correlation). Both chronic active and acute plaques shared the majority of factors identified suggesting that quantitative, rather than gross qualitative differences in gene expression pattern may define the progression from acute to chronic active plaques in MS.
- Published
- 2003
- Full Text
- View/download PDF
16. Immunohistochemical and genetic evidence of myeloperoxidase involvement in multiple sclerosis.
- Author
-
Nagra RM, Becher B, Tourtellotte WW, Antel JP, Gold D, Paladino T, Smith RA, Nelson JR, and Reynolds WF
- Subjects
- Adult, Aged, DNA, Complementary genetics, DNA, Complementary metabolism, Female, Genotype, Humans, Immunohistochemistry, Macrophages metabolism, Male, Microglia metabolism, Middle Aged, Multiple Sclerosis pathology, Peroxidase genetics, RNA, Messenger genetics, RNA, Messenger metabolism, Multiple Sclerosis enzymology, Peroxidase physiology
- Abstract
The myeloperoxidase enzyme (MPO) is expressed specifically in myeloid cells and catalyzes the formation of hypochlorous acid and other cytotoxic oxidants. We previously reported that two alleles of MPO exist which differ in promoter strength due to a base difference in an Alu-encoded hormone response element. The present study shows that the higher expressing MPO genotype is overrepresented in early onset multiple sclerosis in females, implicating MPO in this demyelinating disease. Contrary to the general conception that macrophages lack MPO, immunohistochemical analysis shows that MPO is present in microglia/macrophages in and around MS lesions as shown by colocalization with major histocompatibility antigens HLA-DR and phagocytized myelin. Also, MPO mRNA sequences are detected in cDNA derived from isolated human adult microglia. This is the first evidence that MPO is present in microglia/macrophages at MS lesions, that MPO gene expression occurs in microglia and that MPO plays a role in MS pathogenesis as shown by the allelic disequilibrium in early onset disease.
- Published
- 1997
- Full Text
- View/download PDF
17. Fulminant demyelinating encephalomyelitis associated with productive HHV-6 infection in an immunocompetent adult.
- Author
-
Novoa LJ, Nagra RM, Nakawatase T, Edwards-Lee T, Tourtellotte WW, and Cornford ME
- Subjects
- Adult, Brain pathology, Demyelinating Diseases immunology, Demyelinating Diseases pathology, Demyelinating Diseases physiopathology, Encephalomyelitis immunology, Encephalomyelitis pathology, Encephalomyelitis physiopathology, Fatal Outcome, Female, Herpesviridae Infections immunology, Humans, Immunocompetence, Magnetic Resonance Imaging, Brain virology, Demyelinating Diseases virology, Encephalomyelitis virology, Herpesviridae Infections complications, Herpesvirus 6, Human genetics
- Abstract
Human herpesvirus 6 (HHV-6), the etiologic agent of roseola in young children, has been reported to be detectable in the brain of many neurologically normal adults, although regional localization to plaques of multiple sclerosis has also been demonstrated. Large amounts of this virus were present in multifocal demyelinating white matter lesions of fulminant encephalomyelitis with seizures in a 21-year-old woman with normal immune parameters. Brain biopsy after 3 weeks of neurologic deterioration revealed a viral etiology by light and electron microscopy; the virus was identified as HHV-6 by immunohistochemistry and by polymerase chain reaction (PCR) amplification in biopsy and autopsy specimens.
- Published
- 1997
- Full Text
- View/download PDF
18. Quantifying HIV-1 RNA using the polymerase chain reaction on cerebrospinal fluid and serum of seropositive individuals with and without neurologic abnormalities.
- Author
-
Conrad AJ, Schmid P, Syndulko K, Singer EJ, Nagra RM, Russell JJ, and Tourtellotte WW
- Subjects
- AIDS Dementia Complex blood, AIDS Dementia Complex cerebrospinal fluid, Adult, Base Sequence, Blotting, Southern, CD4 Lymphocyte Count, CD4-Positive T-Lymphocytes virology, Cerebrospinal Fluid virology, DNA Primers chemistry, Gene Products, gag, HIV Seropositivity blood, HIV Seropositivity cerebrospinal fluid, HIV-1 isolation & purification, Humans, Male, Molecular Sequence Data, AIDS Dementia Complex diagnosis, HIV Seropositivity diagnosis, HIV-1 genetics, Polymerase Chain Reaction methods, RNA, Viral blood, RNA, Viral cerebrospinal fluid
- Abstract
We quantified HIV-1 RNA levels (copies per milliliter) in cerebrospinal fluid (CSF) and serum from subjects at various stages of HIV-1 disease and determined the relationship of RNA levels to clinical and neurologic disease status (HND) and to laboratory values. Ninety-seven HIV-1-seropositive men without CNS opportunistic infections, tumors, or neurosyphilis and 13 high-risk seronegative controls were included in the study. Each individual underwent a structured interview and physical and neurologic examinations, followed by standardized collection of blood and CSF. A custom-designed, fully automated polymerase chain reaction (PCR) system was used to perform a minimum of four separate amplifications per specimen, using two HIV-1 gag primer pairs. Southern blotting followed by hybridization with product-specific probes was used for post-PCR detection. The number of copies per milliliter was determined by relating unknowns to a built-in dilution-series standard curve using an image analysis system. HIV-1 RNA was detectable in 96% of the sera, 78% of the concentrated CSF samples, and 54% of the unconcentrated CSF samples. Serum RNA levels were significantly higher than in CSF. Serum RNA levels were significantly inversely correlated with CD4+ cell counts (p = -0.34; p = 0.03): i.e., higher RNA levels in seropositive subjects were associated with lower numbers of CD4+ cells. Serum RNA levels correlated positively with number of AIDS-related symptoms, dysfunction scores for total neurological examination, mental status score, cranial nerve score, and CNS motor signs score. Serum RNA levels did not correlate significantly with length of time on zidovudine therapy, intrathecal IgG synthesis rate, or albumin leakage. RNA levels in CSF significantly correlated only with intrathecal IgG synthesis rate and with serum RNA levels. These results confirm that serum levels of HIV-1 RNA correlate with HND and inversely correlate with CD4 counts, demonstrating that HND occurs predominantly in late stages of HIV-1 disease, although HIV-1 RNA can be detected in CSF from a majority of HIV-1-seropositive individuals at all stages of disease, which suggests that there can be early penetration of HIV into the CNS. However, HND can occur in the absence of high levels of CSF HIV-1 RNA. We also found that the concentration of HIV-1 in CSF is correlated with intrathecal IgG synthesis rate.
- Published
- 1995
- Full Text
- View/download PDF
19. Neocortical pathology in chronic murine retroviral encephalitis.
- Author
-
Nagra RM, Masliah E, Burrola PG, and Wiley CA
- Subjects
- Animals, Cerebral Cortex ultrastructure, Dendrites ultrastructure, Mice, Mice, Inbred Strains, Retroviridae, Cerebral Cortex pathology, Encephalitis pathology, Retroviridae Infections pathology, Tumor Virus Infections pathology
- Abstract
Retroviral infection of the central nervous system (CNS) causes chronic functional and morphological damage in a wide variety of mammals. Neuropathological studies have focused on subcortical pathology, however, the neocortex is also affected. Because studies of human CNS pathology have been limited to the use of material from terminal stages of disease, we used two neuropathogenic murine leukemia virus (MuLV) models to study the development of neocortical damage. MuLV infection caused spongiform change in the spinal cord, brainstem and cerebellum but not in the cerebrum. However, over the course of disease, we observed a reduction of neocortical thickness, accompanied by diminished neuronal and dendritic spine density. Electron microscopic studies showed minimal to no ultrastructural alterations of dendritic spines. Since there was no evidence of extensive direct viral infection of the neocortical neurons or glia at the ultrastructural level, we hypothesize that neocortical damage may be an indirect effect of subcortical retroviral infection.
- Published
- 1994
- Full Text
- View/download PDF
20. Viral load and its relationship to quinolinic acid, TNF alpha, and IL-6 levels in the CNS of retroviral infected mice.
- Author
-
Nagra RM, Heyes MP, and Wiley CA
- Subjects
- Animals, Animals, Newborn, Brain pathology, Brain virology, Brain Stem metabolism, Brain Stem pathology, Brain Stem virology, Female, Mice, Mice, Inbred BALB C, Mice, Inbred C3H, Moloney murine leukemia virus genetics, Mutation, Nervous System Diseases pathology, Pregnancy, Spinal Cord pathology, Spinal Cord virology, Tumor Virus Infections metabolism, Viral Envelope Proteins metabolism, Brain metabolism, Interleukin-6 metabolism, Leukemia Virus, Murine genetics, Leukemia Virus, Murine isolation & purification, Nervous System Diseases virology, Quinolinic Acid metabolism, Retroviridae Infections metabolism, Spinal Cord metabolism, Tumor Necrosis Factor-alpha metabolism
- Abstract
Mouse models of infection of the central nervous system (CNS) have been used to study retroviral-induced neurologic disease. Ecotropic-neurotropic murine leukemia virus (MuLV) infection of susceptible neonatal mice causes a neurologic disease characterized by progressive hindlimb paralysis. The lesions consist of chronic noninflammatory spongiform change predominantly involving brainstem and spinal cord. Two molecularly cloned strains of MuLV, ts-1, a temperature-sensitive mutant of Moloney MuLV, and pNE-8, derived from a feral mouse isolate Cas-Br-E, were used in this study. Infected mice were sacrificed at regular intervals postinoculation throughout the time-course of disease. The neuropathology was evaluated using standard histological and immunohistopathological techniques. Tissue concentrations of viral proteins and potentially cytotoxic factors were compared with the histopathology in select regions of the CNS. Areas of extensive vacuolation with neuronal and oligodendroglial infection were observed in spinal cord, brainstem, and cerebellum. High titers of infectious virus were observed within CNS lesions, whereas low titers were observed in morphologically uninvolved areas. Western blot analysis revealed abundant production of viral envelope proteins, which correlated well with infectious virus titers. Serum quinolinic acid (QUIN) concentrations in both groups of noninfected and infected mice were similar. However, CNS tissue concentrations of QUIN, TNF alpha, and IL-6 in ts-1 infected mice were significantly higher than in pNE-8 infected or noninfected mice. The difference in concentration of these factors may be the result of greater activation of macrophages/microglia in ts-1 infected mice. During murine retroviral encephalitis, CNS damage may be mediated by direct infection of CNS cells and may be enhanced by indirect effects of neurotoxic factors possibly secreted by infected/activated macrophages.
- Published
- 1994
- Full Text
- View/download PDF
21. Detection of cytomegalovirus in cerebrospinal fluid autopsy specimens from AIDS patients.
- Author
-
Achim CL, Nagra RM, Wang R, Nelson JA, and Wiley CA
- Subjects
- Antigens, Viral analysis, Autopsy, Base Sequence, Brain microbiology, Cytomegalovirus Infections complications, DNA Primers, Humans, Molecular Sequence Data, Polymerase Chain Reaction, Sensitivity and Specificity, AIDS-Related Opportunistic Infections cerebrospinal fluid, Cytomegalovirus isolation & purification, Cytomegalovirus Infections cerebrospinal fluid
- Abstract
Cytomegalovirus (CMV) is a common opportunistic pathogen infecting AIDS patients. Polymerase chain reaction (PCR) and antigen capture ELISA were used to detect CMV in 40 cerebrospinal fluid autopsy specimens from patients with AIDS. CMV DNA was detected by PCR in 70% of samples. Of the 21 samples from patients with systemic CMV infection, 57% had CMV encephalitis, while 81% had virus in cerebrospinal fluid detectable by PCR. Of the 24 samples from patients with no histologic evidence of CMV encephalitis, 58% had CMV DNA in cerebrospinal fluid detected by PCR. These results suggest that PCR of cerebrospinal fluid sensitively detects systemic CMV infection but is not specific for brain infection in autopsy specimens of AIDS patients.
- Published
- 1994
- Full Text
- View/download PDF
22. Synaptic and dendritic pathology in murine retroviral encephalitis.
- Author
-
Nagra RM, Masliah E, and Wiley CA
- Subjects
- Animals, Animals, Newborn, Brain ultrastructure, Dendrites ultrastructure, Female, Glial Fibrillary Acidic Protein analysis, Humans, Mice, Mice, Inbred BALB C, Mice, Inbred C3H, Mice, Inbred C57BL, Microtubule-Associated Proteins analysis, Reference Values, Spinal Cord ultrastructure, Spleen pathology, Synapses ultrastructure, Synaptophysin analysis, Brain pathology, Dendrites pathology, Encephalitis pathology, Moloney murine leukemia virus, Retroviridae Infections pathology, Spinal Cord pathology, Synapses pathology, Tumor Virus Infections pathology
- Abstract
Central nervous system (CNS) damage occurs during retroviral infection in both man and animals. As a model of human disease, we studied the distribution and extent of CNS damage during retroviral infection with two molecularly cloned, neurotropic murine leukemia viruses. Both viruses mediate a spongiform encephalopathy involving predominantly the brainstem and spinal cord. During the course of disease, immune reactivity for synaptophysin (SYN) (to identify presynaptic elements) and microtubule-associated protein-2 (MAP-2) (to identify postsynaptic elements) were quantified using confocal laser microscopy. Immunostaining of SYN in the cerebral cortex (an area not exhibiting spongiform lesions) was similar in viral infected and age-matched control mice. However, compared to age matched controls, SYN staining in the brainstem (an area exhibiting spongiform lesions) of viral infected mice progressively declined during the course of disease. Quantitative analysis showed greater reduction of MAP-2 immunostaining in viral-infected mice compared to age-matched controls. In infected mice, both regions with and without spongiform lesions showed diminished MAP-2 staining. Widely distributed microscopic vacuolation of dendritic processes was observed in confocal preparations. These findings suggest primary dendritic damage in murine retroviral infection of the CNS similar to what has been described in human immunodeficiency virus-1 encephalitis.
- Published
- 1993
- Full Text
- View/download PDF
23. Expression of major histocompatibility complex antigens and serum neutralizing antibody in murine retroviral encephalitis.
- Author
-
Nagra RM, Wong PK, and Wiley CA
- Subjects
- Animals, Animals, Newborn, Antibodies, Viral biosynthesis, Brain immunology, Cloning, Molecular, Encephalitis immunology, Friend murine leukemia virus, Gene Expression, Genes, MHC Class II, Leukemia, Experimental immunology, Leukemia, Experimental microbiology, Macrophages pathology, Mice, Mice, Inbred BALB C, Mice, Inbred C3H, Moloney murine leukemia virus, Neoplasm Staging, Neutralization Tests, Tumor Virus Infections immunology, beta 2-Microglobulin biosynthesis, beta 2-Microglobulin genetics, Antibodies, Viral blood, Brain pathology, Encephalitis pathology, Leukemia Virus, Murine, Leukemia, Experimental pathology, Major Histocompatibility Complex, Tumor Virus Infections pathology
- Abstract
Murine leukemia virus infection serves as a model for noninflammatory degeneration of the central nervous system (CNS). During the course of infection with either of the molecularly cloned viruses pNE-8 or ts-1, we observed that ts-1 spread twice as rapidly as pNE-8, and ascended higher in the neuraxis. Endothelial cells were infected first, followed by oligodendrocytes and neurons, while astrocytes containing glial fibrillary acidic protein were not infected. Additionally, ts-1 also infected macrophages/microglia. Major histocompatibility complex (MHC) class I beta 2-microglobulin expression was minimal in pNE-8 infected mice, while it was elevated in endothelial cells of early ts-1 lesions, and in macrophages/microglia during later stages. Occasional infected cells expressed beta 2-microglobulin while rare endothelial and parenchymal cells expressed MHC class II in both viral infections. Limited intra-CNS MHC expression may be one of the mechanisms of viral persistence and will present a barrier to developing immunotherapy for CNS retroviral infections. The few mice that escaped lethal infection had higher serum titers of neutralizing antibodies and showed no neuropathologic changes or detectable virus in the CNS. Higher titers of neutralizing antibodies may protect the CNS from infection.
- Published
- 1993
- Full Text
- View/download PDF
24. Development of spongiform encephalopathy in retroviral infected mice.
- Author
-
Nagra RM, Burrola PG, and Wiley CA
- Subjects
- Animals, Antigens, Viral analysis, Blood-Brain Barrier physiology, Brain microbiology, Brain Diseases pathology, Immunoenzyme Techniques, Leukemia Virus, Murine immunology, Mice, Mice, Inbred BALB C, Retroviridae Infections immunology, Spinal Cord microbiology, Spinal Cord pathology, Viral Proteins analysis, Brain pathology, Brain Diseases microbiology, Retroviridae Infections pathology
- Abstract
The Cas-Br-E strain of murine leukemia virus is a neurovirulent retrovirus that induces progressive noninflammatory degeneration of the central nervous system (CNS). The molecular clone pNE-8 retains pathogenic properties of Cas-Br-E. The neurotropic determinants are known; however, the mechanism of neuropathogenesis is unknown. We examined the temporal development of disease after infection of SWR/J mice with pNE-8 virus. Development of CNS lesions, cellular targets of viral replication, accumulation of ubiquitinated proteins and integrity of blood-brain barrier were determined in mice infected with pNE-8 virus; and compared with uninfected, sham-infected, and nonneuropathogenic virus-infected mice. During 24 weeks of pNE-8 infection, noninflammatory spongiform lesions developed initially in the lumbar spinal cord and progressed to involve the brainstem and deep cerebellar nuclei. Virions and viral antigens accumulated for 18 weeks postinfection and then declined. Major sites of viral infection outside the CNS were splenic megakaryocytes, and skeletal muscle. Cellular targets of viral replication in the CNS included neurons, oligodendrocytes, and capillary endothelium. No astrocytic infection was observed; however, a reactive gliosis marked the development of clinical symptoms and histopathology. Spongiform lesions began as swelling of perivascular astrocytic processes. Intramyelinic vacuoles with splitting of myelin at major dense lines were prominent around dystrophic axons at later time points. Dendritic processes showed vacuolization and local degeneration. Viral particles were most commonly observed in extracellular spaces and within rough endoplasmic reticulum of neurons, oligodendrocytes, and splenic megakaryocytes. Infected megakaryocytes and regions of spleen containing viral aggregates showed accumulation of ubiquitinated proteins. Areas of histopathology in the CNS showed accumulation of ubiquitinated proteins but unlike spleen, viral proteins were not highly ubiquitinated. Disruption of the blood brain barrier was only evident at late stages of infection. In conclusion, the neuropathogenic damage associated with pNE-8 infection appears to be tightly associated with direct viral infection of oligodendroglia and neurons.
- Published
- 1992
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.