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1.
J Biomed Inform ; 145: 104474, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37572825

RESUMO

Inferring knowledge from known relationships between drugs, proteins, genes, and diseases has great potential for clinical impact, such as predicting which existing drugs could be repurposed to treat rare diseases. Incorporating key biological context such as cell type or tissue of action into representations of extracted biomedical knowledge is essential for principled pharmacological discovery. Existing global, literature-derived knowledge graphs of interactions between drugs, proteins, genes, and diseases lack this essential information. In this study, we frame the task of associating biological context with protein-protein interactions extracted from text as a classification task using syntactic, semantic, and novel meta-discourse features. We introduce the Insider corpora, which are automatically generated PubMed-scale corpora for training classifiers for the context association task. These corpora are created by searching for precise syntactic cues of cell type and tissue relevancy to extracted regulatory relations. We report F1 scores of 0.955 and 0.862 for identifying relevant cell types and tissues, respectively, for our identified relations. By classifying with this framework, we demonstrate that the problem of context association can be addressed using intuitive, interpretable features. We demonstrate the potential of this approach to enrich text-derived knowledge bases with biological detail by incorporating cell type context into a protein-protein network for dengue fever.


Assuntos
Mineração de Dados , Bases de Conhecimento , Humanos , PubMed , Doenças Raras
2.
J Immunol ; 205(4): 945-956, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-32641384

RESUMO

C-type lectin CLEC16A is located next to CIITA, the master transcription factor of HLA class II (HLA-II), at a susceptibility locus for several autoimmune diseases, including multiple sclerosis (MS). We previously found that CLEC16A promotes the biogenesis of HLA-II peptide-loading compartments (MIICs) in myeloid cells. Given the emerging role of B cells as APCs in these diseases, in this study, we addressed whether and how CLEC16A is involved in the BCR-dependent HLA-II pathway. CLEC16A was coexpressed with surface class II-associated invariant chain peptides (CLIP) in human EBV-positive and not EBV-negative B cell lines. Stable knockdown of CLEC16A in EBV-positive Raji B cells resulted in an upregulation of surface HLA-DR and CD74 (invariant chain), whereas CLIP was slightly but significantly reduced. In addition, IgM-mediated Salmonella uptake was decreased, and MIICs were less clustered in CLEC16A-silenced Raji cells, implying that CLEC16A controls both HLA-DR/CD74 and BCR/Ag processing in MIICs. In primary B cells, CLEC16A was only induced under CLIP-stimulating conditions in vitro and was predominantly expressed in CLIPhigh naive populations. Finally, CLIP-loaded HLA-DR molecules were abnormally enriched, and coregulation with CLEC16A was abolished in blood B cells of patients who rapidly develop MS. These findings demonstrate that CLEC16A participates in the BCR-dependent HLA-II pathway in human B cells and that this regulation is impaired during MS disease onset. The abundance of CLIP already on naive B cells of MS patients may point to a chronically induced stage and a new mechanism underlying B cell-mediated autoimmune diseases such as MS.


Assuntos
Autoimunidade/imunologia , Linfócitos B/imunologia , Genes MHC da Classe II/imunologia , Lectinas Tipo C/imunologia , Proteínas de Transporte de Monossacarídeos/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Doenças Autoimunes/imunologia , Linhagem Celular , Linhagem Celular Tumoral , Antígenos HLA-DR/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Imunoglobulina M/imunologia , Esclerose Múltipla/imunologia , Transdução de Sinais/imunologia
3.
Ann Neurol ; 87(5): 774-787, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32162725

RESUMO

OBJECTIVE: Multiple sclerosis (MS) is a neurological disease with a substantial genetic component and immune-mediated neurodegeneration. Patients with MS show structural brain differences relative to individuals without MS, including smaller regional volumes and alterations in white matter (WM) microstructure. Whether genetic risk for MS is associated with brain structure during early neurodevelopment remains unclear. In this study, we explore the association between MS polygenic risk scores (PRS) and brain imaging outcomes from a large, population-based pediatric sample to gain insight into the underlying neurobiology of MS. METHODS: We included 8- to 12-year-old genotyped participants from the Generation R Study in whom T1-weighted volumetric (n = 1,136) and/or diffusion tensor imaging (n = 1,088) had been collected. PRS for MS were calculated based on a large genome-wide association study of MS (n = 41,505) and were regressed on regional volumes, global and tract-specific fractional anisotropy (FA), and global mean diffusivity using linear regression. RESULTS: No associations were observed for the regional volumes. We observed a positive association between the MS PRS and global FA (ß = 0.098, standard error [SE] = 0.030, p = 1.08 × 10-3 ). Tract-specific analyses showed higher FA and lower radial diffusivity in several tracts. We replicated our findings in an independent sample of children (n = 186) who were scanned in an earlier phase (global FA; ß = 0.189, SE = 0.072, p = 9.40 × 10-3 ). INTERPRETATION: This is the first study to show that greater genetic predisposition for MS is associated with higher global brain WM FA at an early age in the general population. Our results suggest a preadolescent time window within neurodevelopment in which MS risk variants act upon the brain. ANN NEUROL 2020;87:774-787.


Assuntos
Encéfalo/patologia , Predisposição Genética para Doença/genética , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Criança , Feminino , Genótipo , Humanos , Imageamento por Ressonância Magnética , Masculino , Herança Multifatorial , Neuroimagem
4.
Ann Neurol ; 86(2): 264-278, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31136008

RESUMO

OBJECTIVE: Results from anti-CD20 therapies demonstrate that B- and T-cell interaction is a major driver of multiple sclerosis (MS). The local presence of B-cell follicle-like structures and oligoclonal bands in MS patients indicates that certain B cells infiltrate the central nervous system (CNS) to mediate pathology. Which peripheral triggers underlie the development of CNS-infiltrating B cells is not fully understood. METHODS: Ex vivo flow cytometry was used to assess chemokine receptor profiles of B cells in blood, cerebrospinal fluid, meningeal, and brain tissues of MS patients (n = 10). Similar analyses were performed for distinct memory subsets in the blood of untreated and natalizumab-treated MS patients (n = 38). To assess T-bet(CXCR3)+ B-cell differentiation, we cultured B cells from MS patients (n = 21) and healthy individuals (n = 34) under T helper 1- and TLR9-inducing conditions. Their CNS transmigration capacity was confirmed using brain endothelial monolayers. RESULTS: CXC chemokine receptor 3 (CXCR3)-expressing B cells were enriched in different CNS compartments of MS patients. Treatment with the clinically effective drug natalizumab prevented the recruitment of CXCR3high IgG1+ subsets, corresponding to their increased ability to cross CNS barriers in vitro. Blocking of interferon-γ (IFNγ) reduced the transmigration potential and antigen-presenting function of these cells. IFNγ-induced B cells from MS patients showed increased T-bet expression and plasmablast development. Additional TLR9 triggering further upregulated T-bet and CXCR3, and was essential for IgG1 switching. INTERPRETATION: This study demonstrates that T-bethigh IgG1+ B cells are triggered by IFNγ and TLR9 signals, likely contributing to enhanced CXCR3-mediated recruitment and local reactivity in the CNS of MS patients. ANN NEUROL 2019;86:264-278.


Assuntos
Linfócitos B/metabolismo , Encéfalo/metabolismo , Esclerose Múltipla/metabolismo , Receptores CXCR3/biossíntese , Adulto , Idoso , Animais , Encéfalo/fisiologia , Movimento Celular/fisiologia , Feminino , Expressão Gênica , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Células NIH 3T3 , Receptores CXCR3/genética , Adulto Jovem
5.
EMBO Rep ; 19(9)2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30021835

RESUMO

The cytokine interferon-γ (IFNγ) can induce expression of MHC class II (MHCII) on many different cell types, leading to antigen presentation to CD4+ T cells and immune activation. This has also been linked to anti-tumour immunity and graft-versus-host disease. The extent of MHCII upregulation by IFNγ is cell type-dependent and under extensive control of epigenetic regulators and signalling pathways. Here, we identify novel genetic and chemical factors that control this form of MHCII expression. Loss of the oxidative stress sensor Keap1, autophagy adaptor p62/SQSTM1, ubiquitin E3-ligase Cullin-3 and chromatin remodeller BPTF impair IFNγ-mediated MHCII expression. A similar phenotype is observed for arsenite, an oxidative stressor. Effects of the latter can be reversed by the inhibition of HDAC1/2, linking oxidative stress conditions to epigenetic control of MHCII expression. Furthermore, dimethyl fumarate, an antioxidant used for the treatment of several autoimmune diseases, impairs the IFNγ response by manipulating transcriptional control of MHCII We describe novel pathways and drugs related to oxidative conditions in cells impacting on IFNγ-mediated MHCII expression, which provide a molecular basis for the understanding of MHCII-associated diseases.


Assuntos
Arsenitos/farmacologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Interferon gama/metabolismo , Estresse Oxidativo , Imunidade Adaptativa , Apresentação de Antígeno , Antígenos Nucleares/metabolismo , Antioxidantes/farmacologia , Proteínas Culina/metabolismo , Fumarato de Dimetilo/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Células HeLa , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/imunologia , Humanos , Interferon gama/imunologia , Interferon gama/farmacologia , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteína Sequestossoma-1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/metabolismo , Regulação para Cima/efeitos dos fármacos
6.
Conserv Biol ; 34(3): 721-732, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31702070

RESUMO

Conservation biology was founded on the idea that efforts to save nature depend on a scientific understanding of how it works. It sought to apply ecological principles to conservation problems. We investigated whether the relationship between these fields has changed over time through machine reading the full texts of 32,000 research articles published in 16 ecology and conservation biology journals. We examined changes in research topics in both fields and how the fields have evolved from 2000 to 2014. As conservation biology matured, its focus shifted from ecology to social and political aspects of conservation. The 2 fields diverged and now occupy distinct niches in modern science. We hypothesize this pattern resulted from increasing recognition that social, economic, and political factors are critical for successful conservation and possibly from rising skepticism about the relevance of contemporary ecological theory to practical conservation.


Relaciones entre la Biología de la Conservación y la Ecología Mostradas a través de la Lectura Mediante Máquina de 32,000 Artículos Resumen La biología de la conservación se fundó a partir de la idea de que los esfuerzos para salvar a la naturaleza dependen del entendimiento científico de cómo funciona. La biología de la conservación buscaba aplicar los principios ecológicos a los problemas de conservación. En este trabajo investigamos si la relación entre estos ámbitos ha cambiado con el tiempo al realizar una lectura mediante máquina de 32,000 textos completos de artículos de investigación publicados en 16 revistas sobre ecología y biología de la conservación. También examinamos los cambios en los temas de investigación en ambos ámbitos y cómo éstos han evolucionado desde el año 2000 hasta el 2014. Conforme ha madurado la biología de la conservación, su enfoque se ha movido de los aspectos ecológicos de la conservación a los aspectos políticos y sociales. La ecología y la biología de la conservación se han separado y ahora ocupan nichos distintos dentro de la ciencia moderna. Nuestra hipótesis considera que este patrón resultó de incrementar el reconocimiento de que los factores sociales, económicos y políticos son muy importantes para una conservación exitosa. Posiblemente el patrón también proviene del creciente escepticismo acerca de la relevancia que la teoría ecológica contemporánea tiene para la conservación en práctica.


Assuntos
Conservação dos Recursos Naturais , Ecologia
7.
Eur J Immunol ; 48(11): 1861-1871, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30160778

RESUMO

In MS, B cells survive peripheral tolerance checkpoints to mediate local inflammation, but the underlying molecular mechanisms are relatively underexplored. In mice, the MIF pathway controls B-cell development and the induction of EAE. Here, we found that MIF and MIF receptor CD74 are downregulated, while MIF receptor CXCR4 is upregulated in B cells from early onset MS patients. B cells were identified as the main immune subset in blood expressing MIF. Blocking of MIF and CD74 signaling in B cells triggered CXCR4 expression, and vice versa, with separate effects on their proinflammatory activity, proliferation, and sensitivity to Fas-mediated apoptosis. This study reveals a new reciprocal negative regulation loop between CD74 and CXCR4 in human B cells. The disturbance of this loop during MS onset provides further insights into how pathogenic B cells survive peripheral tolerance checkpoints to mediate disease activity in MS.


Assuntos
Linfócitos B/metabolismo , Oxirredutases Intramoleculares/metabolismo , Fatores Inibidores da Migração de Macrófagos/metabolismo , Esclerose Múltipla/metabolismo , Adulto , Idoso , Antígenos de Diferenciação de Linfócitos B/metabolismo , Apoptose/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Regulação para Baixo/fisiologia , Feminino , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores CXCR4/metabolismo , Transdução de Sinais/fisiologia , Regulação para Cima/fisiologia , Adulto Jovem
8.
Mult Scler ; 25(7): 909-917, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29873607

RESUMO

BACKGROUND: Multiple sclerosis (MS) is a complex disease resulting from the joint effect of many genes. It has been speculated that rare variants might explain part of the missing heritability of MS. OBJECTIVE: To identify rare coding genetic variants by analyzing a large MS pedigree with 11 affected individuals in several generations. METHODS: Genome-wide linkage screen and whole exome sequencing (WES) were performed to identify novel coding variants in the shared region(s) and in the known 110 MS risk loci. The candidate variants were then assessed in 591 MS patients and 3169 controls. RESULTS: Suggestive evidence for linkage was obtained to 7q11.22-q11.23. In WES data, a rare missense variant p.R183C in FKBP6 was identified that segregated with the disease in this family. The minor allele frequency was higher in an independent cohort of MS patients than in healthy controls (1.27% vs 0.95%), but not significant (odds ratio (OR) = 1.33 (95% confidence interval (CI): 0.8-2.4), p = 0.31). CONCLUSION: The rare missense variant in FKBP6 was identified in a large Dutch MS family segregating with the disease. This association to MS was not found in an independent MS cohort. Overall, genome-wide studies in larger cohorts are needed to adequately investigate the role of rare variants in MS risk.


Assuntos
Esclerose Múltipla/genética , Proteínas de Ligação a Tacrolimo/genética , Adulto , Idoso , Feminino , Ligação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Países Baixos , Linhagem , Sequenciamento do Exoma
9.
Mult Scler ; 25(7): 958-967, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-29774770

RESUMO

BACKGROUND: A promising biomarker for axonal damage early in the disease course of multiple sclerosis (MS) is neurofilament light chain (NfL). It is unknown whether NfL has the same predictive value for MS diagnosis in children as in adults. OBJECTIVE: To explore the predictive value of NfL levels in cerebrospinal fluid (CSF) for MS diagnosis in paediatric and adult clinically isolated syndrome (CIS) patients. METHODS: A total of 88 adult and 65 paediatric patients with a first attack of demyelination were included and followed (mean follow up-time in adults: 62.8 months (standard deviation (SD) ±38.7 months) and 43.8 months (SD ±27.1 months) in children). Thirty control patients were also included. Lumbar puncture was done within 6 months after onset of symptoms. NfL was determined in CSF using enzyme-linked immunosorbent assay (ELISA). COX regression analyses were used to calculate hazard ratios (HR) for clinically definite multiple sclerosis (CDMS) diagnosis. RESULTS: After adjustments for age, oligoclonal bands (OCB), and asymptomatic T2 lesions on baseline magnetic resonance imaging (MRI), increased NfL levels in both paediatric and adult CIS patients were associated with a shorter time to CDMS diagnosis (children HR = 3.7; p = 0.007, adults HR = 2.1; p = 0.032). For CIS patients with a future CDMS diagnosis, children showed higher NfL levels than adults (geometric mean 4888 vs 2156 pg/mL; p = 0.007). CONCLUSION: CSF NfL levels are associated with CDMS diagnosis in children and adults with CIS. This makes NfL a promising predictive marker for disease course with potential value in clinical practice.


Assuntos
Progressão da Doença , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/diagnóstico , Proteínas de Neurofilamentos/líquido cefalorraquidiano , Adolescente , Adulto , Biomarcadores/líquido cefalorraquidiano , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/fisiopatologia
10.
Brain ; 141(5): 1334-1349, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29659729

RESUMO

Interleukin-17-expressing CD4+ T helper 17 (Th17) cells are considered as critical regulators of multiple sclerosis disease activity. However, depending on the species and pro-inflammatory milieu, Th17 cells are functionally heterogeneous, consisting of subpopulations that differentially produce interleukin-17, interferon-gamma and granulocyte macrophage colony-stimulating factor. In the current study, we studied distinct effector phenotypes of human Th17 cells and their correlation with disease activity in multiple sclerosis patients. T helper memory populations single- and double-positive for C-C chemokine receptor 6 (CCR6) and CXC chemokine receptor 3 (CXCR3) were functionally assessed in blood and/or cerebrospinal fluid from a total of 59 patients with clinically isolated syndrome, 35 untreated patients and 24 natalizumab-treated patients with relapsing-remitting multiple sclerosis, and nine patients with end-stage multiple sclerosis. Within the clinically isolated syndrome group, 23 patients had a second attack within 1 year and 26 patients did not experience subsequent attacks during a follow-up of >5 years. Low frequencies of T helper 1 (Th1)-like Th17 (CCR6+CXCR3+), and not Th17 (CCR6+CXCR3-) effector memory populations in blood strongly associated with a rapid diagnosis of clinically definite multiple sclerosis. In cerebrospinal fluid of clinically isolated syndrome and relapsing-remitting multiple sclerosis patients, Th1-like Th17 effector memory cells were abundant and showed increased production of interferon-gamma and granulocyte macrophage colony-stimulating factor compared to paired CCR6+ and CCR6-CD8+ T cell populations and their blood equivalents after short-term culturing. Their local enrichment was confirmed ex vivo using cerebrospinal fluid and brain single-cell suspensions. Across all pro-inflammatory T helper cells analysed in relapsing-remitting multiple sclerosis blood, Th1-like Th17 subpopulation T helper 17.1 (Th17.1; CCR6+CXCR3+CCR4-) expressed the highest very late antigen-4 levels and selectively accumulated in natalizumab-treated patients who remained free of clinical relapses. This was not found in patients who experienced relapses during natalizumab treatment. The enhanced potential of Th17.1 cells to infiltrate the central nervous system was supported by their predominance in cerebrospinal fluid of early multiple sclerosis patients and their preferential transmigration across human brain endothelial layers. These findings reveal a dominant contribution of Th1-like Th17 subpopulations, in particular Th17.1 cells, to clinical disease activity and provide a strong rationale for more specific and earlier use of T cell-targeted therapy in multiple sclerosis.


Assuntos
Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Esclerose Múltipla/terapia , Células Th17/fisiologia , Adulto , Encéfalo/patologia , Movimento Celular/fisiologia , Estudos de Coortes , Citocinas/genética , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Fatores Imunológicos/uso terapêutico , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/metabolismo , Natalizumab/uso terapêutico , RNA Mensageiro/metabolismo , Estatísticas não Paramétricas , Células Th17/efeitos dos fármacos
11.
Mult Scler ; 24(7): 982-990, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28445083

RESUMO

BACKGROUND AND OBJECTIVE: Fatigue and physical impairments are a major concern in children with multiple sclerosis (MS) and after acute disseminated encephalomyelitis (post-ADEM). We here aimed to evaluate the interaction between fatigue, exercise capacity, motor performance, neurological status, and quality of life (HRQoL). METHODS: In this cross-sectional study, data of 38 children (MS n = 22, post-ADEM n = 16), aged 4-17 years attending our national pediatric MS center, were studied. Fatigue was measured with the Pediatric Quality of Life Multidimensional Fatigue Scale, exercise capacity with the Bruce Protocol, motor performance with the Movement Assessment Battery for Children second edition, HRQoL with the Pediatric Quality of Life Questionnaire, and extent of disability with the Expanded Disability Status Scale (EDSS). RESULTS: Children with MS and post-ADEM experienced more fatigue ( p < 0.001), reduced exercise capacity ( p < 0.001), and impaired motor performance ( p < 0.001), despite low scores on the EDSS. Fatigue, but not the other parameters, was significantly correlated with HRQoL. Fatigue was not correlated with exercise capacity. CONCLUSION: We confirm the major impact of fatigue on quality of life in children with MS and post-ADEM. Fatigue was not explained by reduced exercise capacity or impaired motor performance. An important finding for clinical practice is that the low EDSS score did not reflect the poor physical functioning.


Assuntos
Encefalomielite Aguda Disseminada/complicações , Fadiga/epidemiologia , Fadiga/etiologia , Esclerose Múltipla/complicações , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Avaliação da Deficiência , Feminino , Humanos , Masculino , Qualidade de Vida
12.
Mult Scler ; 24(13): 1715-1724, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30019626

RESUMO

BACKGROUND: Cerebrospinal fluid (CSF) levels of T-cell activation marker soluble CD27 (sCD27) are associated with subsequent disease activity after a first attack of suspected MS in adults. The predictive value for disease course in children with acquired demyelinating syndromes (ADS) is unknown. OBJECTIVES: To assess the predictive value of sCD27 levels for clinically definite multiple sclerosis (CDMS) diagnosis in childhood ADS. METHODS: Children <18 years with a first demyelinating event were prospectively included and followed. Soluble CD27 was determined in CSF using an enzyme-linked immunosorbent assay (ELISA). Cox regression analyses were used to calculate hazard ratios (HRs) for CDMS. RESULTS: A total of 94 ADS children were included (ADS with encephalopathy (ADS+) n = 33 and ADS without encephalopathy (ADS-) n = 61). Of the 61 ADS- children, 21 (48%) were diagnosed with CDMS during follow-up. At baseline, sCD27 levels were higher in patients with a future CDMS diagnosis ( n = 29) than in monophasic ADS+ ( n = 30), monophasic ADS- ( n = 28) and relapsing non-MS patients ( n = 7; p < 0.001). In ADS- patients, sCD27 was associated with CDMS (HR = 1.8 per 100 U/mL increase in sCD27 levels, p = 0.031), after adjustments for age, oligoclonal bands and the presence of dissemination in space on baseline magnetic resonance imaging (MRI). CONCLUSION: CSF sCD27 levels at first attack of demyelination were associated with CDMS diagnosis in children. This makes sCD27 a potential clinically relevant quantitative marker when performing routine CSF diagnostics.


Assuntos
Doenças Desmielinizantes/imunologia , Esclerose Múltipla/imunologia , Linfócitos T/imunologia , Membro 7 da Superfamília de Receptores de Fatores de Necrose Tumoral/metabolismo , Progressão da Doença , Humanos , Imageamento por Ressonância Magnética/métodos , Esclerose Múltipla/diagnóstico , Estudos Prospectivos , Medula Espinal/imunologia , Síndrome
13.
Mult Scler ; 24(7): 974-981, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28532229

RESUMO

BACKGROUND: Fatigue is reported by more than 75% of multiple sclerosis (MS) patients. In an earlier study, we showed that fatigue is not only a common symptom in patients at time of clinically isolated syndrome (CIS; fatigued 46%) but also predicts subsequent diagnosis of clinically definite multiple sclerosis (CDMS). The course of fatigue after CIS is unknown. OBJECTIVE: We aimed to explore the long-term course of fatigue after CIS. METHODS: In this study, 235 CIS patients, aged 18-50 years, were prospectively followed. Patients filled in the Krupp's Fatigue Severity Scale (FSS) and the Hospital Anxiety and Depression Scale (HADS) at baseline and annually. After reaching CDMS diagnosis, Expanded Disability Status Scale (EDSS) was obtained annually. Mixed-effects models were used to analyse longitudinal FSS measurements. RESULTS: Fatigue at baseline was an independent predictor for CDMS diagnosis (hazard ratio (HR): 2.6, 95% confidence interval (CI): 1.6-4.4). The evolution of FSS was the same in CIS patients who remained monophasic and patients who were diagnosed with CDMS during follow-up. However, FSS increased by 0.86 units after reaching CDMS diagnosis ( p = 0.01). After this increase, the FSS course remained unaltered ( p = 0.44). CONCLUSION: Fatigue, which is often present at time of CIS, probably persists over time and increases after a second attack.


Assuntos
Doenças Desmielinizantes/complicações , Fadiga/epidemiologia , Fadiga/etiologia , Esclerose Múltipla/complicações , Adulto , Avaliação da Deficiência , Progressão da Doença , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
14.
Eur J Immunol ; 46(2): 347-53, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26507805

RESUMO

MS pathology is potentially orchestrated by autoreactive T cells, but the antigens recognized remain unknown. A novel APC/T-cell platform was developed to determine intrathecal CD4(+) and CD8(+) T-cell responses to candidate MS-associated autoantigens (cMSAg) in clinically isolated syndrome (CIS, n = 7) and MS (n = 6) patients. Human cMSAg encoding open reading frames (n = 8) were cloned into an Epstein-Barr virus (EBV)-based vector to express cMSAg at high levels in EBV-transformed B-cells (BLCLs). Human cMSAg cloned were myelin-associated and -oligodendrocyte glycoprotein, myelin basic protein, proteolipid protein, ATP-dependent potassium channel ATP-dependent inwards rectifying potassium channel 4.1, S100 calcium-binding protein B, contactin-2, and neurofascin. Transduced BLCLs were used as autologous APC in functional T-cell assays to determine cMSAg-specific T-cell frequencies in cerebrospinal fluid derived T-cell lines (CSF-TCLs) by intracellular IFN-γ flow cytometry. Whereas all CSF-TCL responded strongly to mitogenic stimulation, no substantial T-cell reactivity to cMSAg was observed. Contrastingly, measles virus fusion protein-specific CD4(+) and CD8(+) T-cell clones, used as control of the APC/T-cell platform, efficiently recognized transduced BLCL expressing their cognate antigen. The inability to detect substantial T-cell reactivity to eight human endogenously synthesized cMSAg in autologous APC do not support their role as prominent intrathecal T-cell target antigens in CIS and MS patients early after onset of disease.


Assuntos
Linfócitos B/fisiologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Vírus do Sarampo/imunologia , Esclerose Múltipla/imunologia , Traqueia/imunologia , Proteínas Virais de Fusão/imunologia , Adulto , Células Apresentadoras de Antígenos , Autoantígenos/imunologia , Linfócitos B/metabolismo , Líquido Cefalorraquidiano/imunologia , Feminino , Humanos , Interferon gama/metabolismo , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
J Neuroinflammation ; 14(1): 235, 2017 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-29202778

RESUMO

BACKGROUND: Multiple sclerosis (MS) is a demyelinating and degenerative disease of the central nervous system. Normally, demyelination is followed by remyelination, which requires repopulation of a demyelinated area by oligodendrocyte precursor cells. Although large numbers of precursor cells are present in MS lesions, remyelination often fails, in part by the inability of precursor cells to differentiate into mature myelin-forming cells. In mouse and rat, miR-219 is required for this differentiation. Previously, we identified decreased miR-219 expression in tissue of MS patients compared to controls. Cell-free miRNAs have been detected in many different body fluids including cerebrospinal fluid (CSF) and may reflect disease processes going on in the central nervous system. This prompted us to investigate the biomarker performance of CSF miR-219 for MS diagnosis. METHODS: Quantitative PCR was performed measuring miR-219 levels in CSF of MS patients and controls in three independent cohorts. RESULTS: All three cohorts of MS patients and controls revealed that absence of miR-219 detection in CSF is consistently associated with MS. CONCLUSIONS: We have been able to identify and validate absence of miR-219 detection in CSF of MS patients compared to controls, suggesting that it may emerge as a candidate biomarker for MS diagnosis.


Assuntos
Biomarcadores/líquido cefalorraquidiano , MicroRNAs/líquido cefalorraquidiano , Esclerose Múltipla/líquido cefalorraquidiano , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Acta Neuropathol ; 134(1): 1-14, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28315956

RESUMO

The transport of mitochondria and other cellular components along the axonal microtubule cytoskeleton plays an essential role in neuronal survival. Defects in this system have been linked to a large number of neurological disorders. In multiple sclerosis (MS) and associated models such as experimental autoimmune encephalomyelitis (EAE), alterations in axonal transport have been shown to exist before neurodegeneration occurs. Genome-wide association (GWA) studies have linked several motor proteins to MS susceptibility, while neuropathological studies have shown accumulations of proteins and organelles suggestive for transport deficits. A reduced effectiveness of axonal transport can lead to neurodegeneration through inhibition of mitochondrial motility, disruption of axoglial interaction or prevention of remyelination. In MS, demyelination leads to dysregulation of axonal transport, aggravated by the effects of TNF-alpha, nitric oxide and glutamate on the cytoskeleton. The combined effect of all these pathways is a vicious cycle in which a defective axonal transport system leads to an increase in ATP consumption through loss of membrane organization and a reduction in available ATP through inhibition of mitochondrial transport, resulting in even further inhibition of transport. The persistent activity of this positive feedback loop contributes to neurodegeneration in MS.


Assuntos
Transporte Axonal/fisiologia , Esclerose Múltipla/metabolismo , Animais , Humanos
17.
Acta Neuropathol ; 134(3): 383-401, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28624961

RESUMO

T cells are considered pivotal in the pathology of multiple sclerosis (MS), but their function and antigen specificity are unknown. To unravel the role of T cells in MS pathology, we performed a comprehensive analysis on T cells recovered from paired blood, cerebrospinal fluid (CSF), normal-appearing white matter (NAWM) and white matter lesions (WML) from 27 MS patients with advanced disease shortly after death. The differentiation status of T cells in these compartments was determined by ex vivo flow cytometry and immunohistochemistry. T-cell reactivity in short-term T-cell lines (TCL), generated by non-specific stimulation of T cells recovered from the same compartments, was determined by intracellular cytokine flow cytometry. Central memory T cells predominated in CSF and effector memory T cells were enriched in NAWM and WML. WML-derived CD8+ T cells represent chronically activated T cells expressing a cytotoxic effector phenotype (CD95L and granzyme B) indicative for local antigenic stimulation (CD137). The same lesions also contained higher CD8+ T-cell frequencies expressing co-inhibitory (TIM3 and PD1) and co-stimulatory (ICOS) T-cell receptors, yet no evidence for T-cell senescence (CD57) was observed. The oligoclonal T-cell receptor (TCR) repertoire, particularly among CD8+ T cells, correlated between TCL generated from anatomically separated WML of the same MS patient, but not between paired NAWM and WML. Whereas no substantial T-cell reactivity was detected towards seven candidate human MS-associated autoantigens (cMSAg), brisk CD8+ T-cell reactivity was detected in multiple WML-derived TCL towards autologous Epstein-Barr virus (EBV) infected B cells (autoBLCL). In one MS patient, the T-cell response towards autoBLCL in paired intra-lesional TCL was dominated by TCRVß2+CD8+ T cells, which were localized in the parenchyma of the respective tissues expressing a polarized TCR and CD8 expression suggesting immunological synapse formation in situ. Collectively, the data suggest the involvement of effector memory cytotoxic T cells recognizing antigens expressed by autoBLCL, but not the assayed human cMSAg, in WML of MS patients.


Assuntos
Linfócitos T CD8-Positivos/patologia , Esclerose Múltipla/patologia , Substância Branca/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade
18.
Mult Scler ; 23(13): 1697-1706, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28273768

RESUMO

BACKGROUND: Multiple sclerosis (MS) affects brain structure and cognitive function and has a heritable component. Over a 100 common genetic risk variants have been identified, but most carriers do not develop MS. For other neurodegenerative diseases, risk variants have effects outside patient populations, but this remains uninvestigated for MS. OBJECTIVES: To study the effect of MS-associated genetic variants on brain structure and cognitive function in the general population. METHODS: We studied middle-aged and elderly individuals (mean age = 65.7 years) from the population-based Rotterdam Study. We determined 107 MS variants and additionally created a risk score combining all variants. Magnetic resonance imaging ( N = 4710) was performed to obtain measures of brain macrostructure, white matter microstructure, and gray matter voxel-based morphometry. A cognitive test battery ( N = 7556) was used to test a variety of cognitive domains. RESULTS: The MS risk score was associated with smaller gray matter volume over the whole brain (ßstandardized = -0.016; p = 0.044), but region-specific analyses did not survive multiple testing correction. Similarly, no significant associations with brain structure were observed for individual variants. For cognition, rs2283792 was significantly associated with poorer memory (ß = -0.064; p = 3.4 × 10-5). CONCLUSION: Increased genetic susceptibility to MS may affect brain structure and cognition in persons without disease, pointing to a "hidden burden" of MS.


Assuntos
Disfunção Cognitiva/fisiopatologia , Predisposição Genética para Doença , Esclerose Múltipla/genética , Esclerose Múltipla/patologia , Esclerose Múltipla/fisiopatologia , Idoso , Disfunção Cognitiva/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Países Baixos
19.
Neurourol Urodyn ; 36(1): 116-120, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-26493281

RESUMO

AIMS: The objective of this study was to determine the prevalence of female sexual dysfunction (FSD) in patients with Multiple Sclerosis (MS) in one of the leading MS centers in the Netherlands. Furthermore, we evaluated the practice patterns of members of the Dutch Urological Association (DUA) with respect to FSD. METHODS: A self-administered Web-based questionnaire for physicians was mailed to all 467 members of the DUA. The questions covered different topics in female sexuality. For the patient survey the Female Sexual Function Index (FSFI) was used. RESULTS: The response rate of the physicians survey was 42% (n = 194). Sixty-one percent of the responders reported to ask their female patients about their sexual function. Thirty-nine percent of the physicians did not ask their patients about sexuality. The majority indicated that they lacked knowledge on FSD or found discussing sexuality not relevant for their practice. The response rate of the patient survey was 28% (n = 85). According to the FSFI questionnaire 32% of the sexually active MS patients experienced FSD. Women with FSD scored low on all subdomains of the FSFI questionnaire. In particular, desire, arousal, lubrication, and the ability to achieve orgasm were affected. CONCLUSIONS: The prevalence of FSD in MS patients in our center is about 32%. Overall, many members of the DUA do not screen for sexual dysfunction in female patients because of lack of knowledge on FSD. Better and more structured education of urologists and residents in urology on FSD in The Netherlands is urgently needed. Neurourol. Urodynam. 36:116-120, 2017. © 2015 Wiley Periodicals, Inc.


Assuntos
Esclerose Múltipla/complicações , Esclerose Múltipla/epidemiologia , Disfunções Sexuais Fisiológicas/epidemiologia , Disfunções Sexuais Fisiológicas/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Países Baixos/epidemiologia , Pacientes , Prevalência , Disfunções Sexuais Psicogênicas/epidemiologia , Disfunções Sexuais Psicogênicas/etiologia , Inquéritos e Questionários , Urologistas , Adulto Jovem
20.
J Neurol Neurosurg Psychiatry ; 87(9): 1005-15, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27113605

RESUMO

OBJECTIVE: Antibodies to cell surface central nervous system proteins help to diagnose conditions which often respond to immunotherapies. The assessment of antibody assays needs to reflect their clinical utility. We report the results of a multicentre study of aquaporin (AQP) 4 antibody (AQP4-Ab) assays in neuromyelitis optica spectrum disorders (NMOSD). METHODS: Coded samples from patients with neuromyelitis optica (NMO) or NMOSD (101) and controls (92) were tested at 15 European diagnostic centres using 21 assays including live (n=3) or fixed cell-based assays (n=10), flow cytometry (n=4), immunohistochemistry (n=3) and ELISA (n=1). RESULTS: Results of tests on 92 controls identified 12assays as highly specific (0-1 false-positive results). 32 samples from 50 (64%) NMO sera and 34 from 51 (67%) NMOSD sera were positive on at least two of the 12 highly specific assays, leaving 35 patients with seronegative NMO/spectrum disorder (SD). On the basis of a combination of clinical phenotype and the highly specific assays, 66 AQP4-Ab seropositive samples were used to establish the sensitivities (51.5-100%) of all 21 assays. The specificities (85.8-100%) were based on 92 control samples and 35 seronegative NMO/SD patient samples. CONCLUSIONS: The cell-based assays were most sensitive and specific overall, but immunohistochemistry or flow cytometry could be equally accurate in specialist centres. Since patients with AQP4-Ab negative NMO/SD require different management, the use of both appropriate control samples and defined seronegative NMOSD samples is essential to evaluate these assays in a clinically meaningful way. The process described here can be applied to the evaluation of other antibody assays in the newly evolving field of autoimmune neurology.


Assuntos
Aquaporina 4/sangue , Autoanticorpos/sangue , Neuromielite Óptica/sangue , Aquaporina 4/imunologia , Autoanticorpos/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Humanos , Imuno-Histoquímica/métodos , Neuromielite Óptica/imunologia , Sensibilidade e Especificidade
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