RESUMO
Clonally related B cells infiltrate the brain, meninges, and cerebrospinal fluid of MS patients, but the mechanisms driving the B-cell response and shaping the immunoglobulin repertoires remain unclear. Here, we used single-cell full-length RNA-seq and BCR reconstruction to simultaneously assess the phenotypes, isotypes, constant region polymorphisms, and the paired heavy- and light-chain repertoires in intrathecal B cells. We detected extensive clonal connections between the memory B cell and antibody-secreting cell (ASC) compartments and observed clonally related cells of different isotypes including IgM/IgG1, IgG1/IgA1, IgG1/IgG2, and IgM/IgA1. There was a strong dominance of the G1m1 allotype constant region polymorphisms in ASCs, but not in memory B cells. Tightly linked to the G1m1 allotype, we found a preferential pairing of the immunoglobulin heavy-chain variable (IGHV)4 gene family with the κ variable (IGKV)1 gene family. The IGHV4-39 gene was most used and showed the highest frequency of pairing with IGKV1-5 and IGKV1(D)-33. These results link IgG constant region polymorphisms to stereotyped B-cell responses in MS and indicate that the intrathecal B-cell response in these patients could be directed against structurally similar epitopes.
Assuntos
Esclerose Múltipla , Linfócitos B , Encéfalo , Humanos , Imunoglobulina A , Imunoglobulina G , Esclerose Múltipla/genéticaRESUMO
Cysteine cathepsins are critical components of the adaptive immune system involved in the generation of epitopes for presentation on human leukocyte antigen (HLA) molecules and have been implicated in degradation of autoantigens. Immunoglobulin variable regions with somatic mutations and random complementarity region 3 amino acid composition are inherently immunogenic. T cell reactivity towards immunoglobulin variable regions has been investigated in relation to specific diseases, as well as reactivity to therapeutic monoclonal antibodies. Yet, how the immunoglobulins, or the B cell receptors, are processed in endolysosomal compartments of professional antigen presenting cells has not been described in detail. Here we present in silico and in vitro experimental evidence suggesting that cysteine cathepsins S, L and B may have important roles in generating peptides fitting HLA class II molecules, capable of being presented to T cells, from monoclonal antibodies as well as from central nervous system proteins including a well described autoantigen. By combining neural net models with in vitro proteomics experiments, we further suggest how such degradation can be predicted, how it fits with available cellular models, and that it is immunoglobulin heavy chain variable family dependent. These findings are relevant for biotherapeutic drug design as well as to understand disease development. We also suggest how these tools can be improved, including improved machine learning methodology.
Assuntos
Catepsinas/química , Catepsinas/metabolismo , Cisteína/metabolismo , Imunoglobulina G/química , Imunoglobulina G/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Imunoglobulina G/genética , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/metabolismo , Conformação Molecular , Ligação Proteica , Proteólise , Reprodutibilidade dos Testes , Relação Estrutura-AtividadeRESUMO
BACKGROUND: Elevated antibody levels against Epstein-Barr virus (EBV) and a poor vitamin D status are environmental factors that may interact in relapsing-remitting multiple sclerosis (RRMS) aetiology. OBJECTIVES: To examine effects of high-dose oral vitamin D3 supplementation on antibody levels against EBV nuclear antigen 1 (EBNA1) in RRMS. METHODS: Serum 25-hydroxyvitamin D3 (25(OH)D) and immunoglobulin G antibody levels against EBNA1 (whole protein and amino acid 385-420 fragment), EBV viral capsid antigen (VCA), cytomegalovirus (CMV) and varicella zoster virus (VZV) were measured in 68 RRMS patients enrolled in a 96-week randomised double-blinded placebo-controlled clinical trial of oral vitamin D3 supplementation (20,000 IU/week) (NCT00785473). RESULTS: The mean 25(OH)D level more than doubled in the vitamin D group and was significantly higher than in the placebo group at study conclusion (123.2 versus 61.8 nmol/L, p < 0.001). Compared to the placebo group, both anti-EBNA1 protein and fragment antibody levels decreased in the vitamin D group from baseline to week 48 ( p = 0.038 and p = 0.004, respectively), but not from baseline to week 96. Vitamin D3 supplementation did not affect antibodies against VCA, CMV or VZV. CONCLUSION: The results indicate that high-dose oral vitamin D3 supplementation can affect humoral immune responses against the latent EBV antigen EBNA1 in RRMS.
Assuntos
Colecalciferol/uso terapêutico , Infecções por Vírus Epstein-Barr/tratamento farmacológico , Herpesvirus Humano 4/efeitos dos fármacos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Adolescente , Adulto , Anticorpos Antivirais/sangue , Infecções por Vírus Epstein-Barr/imunologia , Antígenos Nucleares do Vírus Epstein-Barr/sangue , Feminino , Herpesvirus Humano 4/patogenicidade , Humanos , Imunoglobulina G/sangue , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
The mechanisms driving the intrathecal synthesis of IgG in multiple sclerosis (MS) are unknown. We combined high-throughput sequencing of transcribed immunoglobulin heavy-chain variable (IGHV) genes and mass spectrometry to chart the diversity and compartmentalization of IgG-producing B cells in the cerebrospinal fluid (CSF) of MS patients and controls with other neuroinflammatory diseases. In both groups, a few clones dominated the intrathecal IGHV transcriptome. In most MS patients and some controls, dominant transcripts matched the CSF IgG. The IGHV transcripts in CSF of MS patients frequently carried IGHV4 genes and had more replacement mutations compared to controls. In both groups, dominant IGHV transcripts were identified within clusters of clonally related B cells that had identical or related IGHV transcripts in the blood. These findings suggest more pronounced affinity maturation, but an equal degree of diversity and compartmentalization of the intrathecal B-cell response in MS compared to other neuroinflammatory diseases.
Assuntos
Linfócitos B/imunologia , Cadeias Pesadas de Imunoglobulinas/genética , Esclerose Múltipla Recidivante-Remitente/genética , RNA Mensageiro/líquido cefalorraquidiano , Adulto , Doenças do Sistema Nervoso Central/líquido cefalorraquidiano , Doenças do Sistema Nervoso Central/genética , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Cadeias Pesadas de Imunoglobulinas/líquido cefalorraquidiano , Cadeias Pesadas de Imunoglobulinas/imunologia , Masculino , Meningite Asséptica/líquido cefalorraquidiano , Meningite Asséptica/genética , Meningoencefalite/líquido cefalorraquidiano , Meningoencefalite/genética , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Polirradiculopatia/líquido cefalorraquidiano , Polirradiculopatia/genética , Proteoma , Sarcoidose/líquido cefalorraquidiano , Sarcoidose/genética , Transcriptoma/imunologiaRESUMO
Epstein-Barr virus (EBV) has long been suggested as a pathogen in multiple sclerosis (MS). Here, we used high-throughput sequencing to determine the diversity, compartmentalization, persistence, and EBV-reactivity of the T-cell receptor (TCR) repertoires in MS. TCR-ß genes were sequenced in paired samples of cerebrospinal fluid (CSF) and blood from patients with MS and controls with other inflammatory neurological diseases. The TCR repertoires were highly diverse in both compartments and patient groups. Expanded T-cell clones, represented by TCR-ß sequences >0.1%, were of different identity in CSF and blood of MS patients, and persisted for more than a year. Reference TCR-ß libraries generated from peripheral blood T cells reactive against autologous EBV-transformed B cells were highly enriched for public EBV-specific sequences and were used to quantify EBV-reactive TCR-ß sequences in CSF. TCR-ß sequences of EBV-reactive CD8+ T cells, including several public EBV-specific sequences, were intrathecally enriched in MS patients only, whereas those of EBV-reactive CD4+ T cells were also enriched in CSF of controls. These data provide evidence for a clonally diverse, yet compartmentalized and persistent, intrathecal T-cell response in MS. The presented strategy links TCR sequence to intrathecal T-cell specificity, demonstrating enrichment of EBV-reactive CD8+ T cells in MS.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Herpesvirus Humano 4/imunologia , Esclerose Múltipla/imunologia , Receptores de Antígenos de Linfócitos T alfa-beta/sangue , Adulto , Linfócitos B/imunologia , Linfócitos B/virologia , Sequência de Bases , Linfócitos T CD8-Positivos/virologia , Feminino , Antígenos HLA-A/imunologia , Antígenos HLA-B/imunologia , Cadeias HLA-DRB1/imunologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mononucleose Infecciosa/imunologia , Mononucleose Infecciosa/virologia , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/virologia , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Análise de Sequência de DNA , Adulto JovemRESUMO
BACKGROUND: Obesity may be a risk factor for developing multiple sclerosis (MS). OBJECTIVE: We examined if body size influences the risk of MS in a population-based, case control study. METHODS: A total of 953 cases and 1717 controls from Norway and 707 cases and 1333 controls from Italy reported their body size by choosing a silhouette 1 to 9 (largest) every fifth year from age 5 to 30 and at time of study. The body size-related MS risk was defined by odds ratios (ORs) in logistic regression analyses adjusting for age, smoking and outdoor activity. RESULTS: In Norway a large body size (silhouettes 6-9) compared to silhouette 3 increased the risk of MS, especially at age 25 (OR 2.21; 95% CI 1.09-4.46 for men and OR 1.43; 95% CI 0.90-2.27 for women). When comparing silhouette 9 to 1, we found a significant dose-response from age 10 until age 30 peaking at age 25 (sex-adjusted OR 2.83; 95% CI 1.68-4.78). The association was present for at least 15 years prior to disease onset. No significant associations were found in Italy. CONCLUSIONS: Obesity from childhood until young adulthood is a likely risk factor for MS with a seemingly stronger effect in Norway than in Italy.
Assuntos
Tamanho Corporal , Esclerose Múltipla/epidemiologia , Obesidade/epidemiologia , Adolescente , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Feminino , Humanos , Itália/epidemiologia , Masculino , Noruega/epidemiologia , Razão de Chances , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Epidemiological studies suggest that environmental factors play a significant role in the development of multiple sclerosis. This article presents current knowledge on the impact of the environment on disease risk and disease course. METHOD: We have conducted searches in PubMed for «multiple sclerosis¼ combined with «environment¼ as well as relevant environmental factors. RESULTS: It is highly likely that an interaction between genetic and environmental factors determines who will develop multiple sclerosis. Epstein-Barr virus infection, smoking, and low vitamin D levels are the environmental factors that have shown the strongest and most consistent association with development of the disease. Low vitamin D levels are also associated with high disease activity. Other risk factors include obesity and high salt intake. INTERPRETATION: Although epidemiological studies have identified a number of environmental factors with potential aetiological relevance, and the importance of these is supported by experimental studies, there is still insufficient evidence to establish a causal role for these factors in multiple sclerosis.
Assuntos
Exposição Ambiental/efeitos adversos , Esclerose Múltipla/etiologia , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/fisiopatologia , Humanos , Linfócitos/fisiologia , Esclerose Múltipla/fisiopatologia , Obesidade/complicações , Fatores de Risco , Fumar/efeitos adversos , Fumar/fisiopatologia , Cloreto de Sódio na Dieta/efeitos adversos , Cloreto de Sódio na Dieta/metabolismo , Deficiência de Vitamina D/complicações , Deficiência de Vitamina D/fisiopatologiaRESUMO
OBJECTIVES: The objective of this paper is to estimate the association between multiple sclerosis (MS) and measures of sun exposure in specific age periods in Norway and Italy. METHODS: A total of 1660 MS patients and 3050 controls from Italy and Norway who participated in a multinational case-control study (EnvIMS) reported sun habits during childhood and adolescence. RESULTS: A significant association between infrequent summer outdoor activity and increased MS risk was found in Norway and in Italy. The association was strongest between the ages of 16 and 18 years in Norway (odds ratio (OR) 1.83, 95% confidence interval (CI) 1.30-2.59), and between birth and age 5 years in Italy (OR 1.56, 95% CI 1.16-2.10). In Italy a significant association was also found during winter (OR 1.42, 95% CI 1.03-1.97). Frequent sunscreen use between birth and the age of 6 years was associated with MS in Norway (OR 1.44, 95% CI 1.08-1.93) after adjusting for outdoor activity during the same period. Red hair (OR 1.67, 95% CI 1.06-2.63) and blonde hair (OR 1.36, 95% CI 1.09-1.70) were associated with MS after adjusting for outdoor activity and sunscreen use. CONCLUSION: Converging evidence from different measures underlines the beneficial effect of sun exposure on MS risk.
Assuntos
Esclerose Múltipla/epidemiologia , Luz Solar , Adolescente , Adulto , Idade de Início , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Cor de Cabelo , Humanos , Lactente , Recém-Nascido , Itália/epidemiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/prevenção & controle , Noruega/epidemiologia , Razão de Chances , Fatores de Proteção , Medição de Risco , Fatores de Risco , Estações do Ano , Protetores Solares/administração & dosagem , Fatores de Tempo , Adulto JovemRESUMO
BACKGROUND: Seasonal fluctuations in solar radiation and vitamin D levels could modulate the immune response against Epstein-Barr virus (EBV) infection and influence the subsequent risk of multiple sclerosis (MS). METHODS: Altogether 1660 MS patients and 3050 controls from Norway and Italy participating in the multinational case-control study of Environmental Factors In Multiple Sclerosis (EnvIMS) reported season of past infectious mononucleosis (IM). RESULTS: IM was generally reported more frequently in Norway (p=0.002), but was associated with MS to a similar degree in Norway (odds ratio (OR) 2.12, 95% confidence interval (CI) 1.64-2.73) and Italy (OR 1.72, 95% CI 1.17-2.52). For all participants, there was a higher reported frequency of IM during spring compared to fall (p<0.0005). Stratified by season of IM, the ORs for MS were 1.58 in spring (95% CI 1.08-2.31), 2.26 in summer (95% CI 1.46-3.51), 2.86 in fall (95% CI 1.69-4.85) and 2.30 in winter (95% CI 1.45-3.66). CONCLUSIONS: IM is associated with MS independently of season, and the association is not stronger for IM during spring, when vitamin D levels reach nadir. The distribution of IM may point towards a correlation with solar radiation or other factors with a similar latitudinal and seasonal variation.
Assuntos
Infecções por Vírus Epstein-Barr/virologia , Mononucleose Infecciosa/epidemiologia , Esclerose Múltipla/epidemiologia , Estações do Ano , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Mononucleose Infecciosa/complicações , Mononucleose Infecciosa/virologia , Itália , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/virologia , Noruega , Risco , Vitamina D/metabolismoRESUMO
The phenotypes of B lineage cells that produce oligoclonal IgG in multiple sclerosis have not been unequivocally determined. Here, we utilized single-cell RNA-seq data of intrathecal B lineage cells in combination with mass spectrometry of intrathecally synthesized IgG to identify its cellular source. We found that the intrathecally produced IgG matched a larger fraction of clonally expanded antibody-secreting cells compared to singletons. The IgG was traced back to two clonally related clusters of antibody-secreting cells, one comprising highly proliferating cells, and the other consisting of more differentiated cells expressing genes associated with immunoglobulin synthesis. These findings suggest some degree of heterogeneity among cells that produce oligoclonal IgG in multiple sclerosis.
RESUMO
BACKGROUND: T cells play a key role in the pathogenesis of multiple sclerosis (MS), a chronic, inflammatory, demyelinating disease of the central nervous system (CNS). Although several studies recently investigated the T-cell receptor (TCR) repertoire in cerebrospinal fluid (CSF) of MS patients by high-throughput sequencing (HTS), a deep analysis on repertoire similarities and differences among compartments is still missing. METHODS: We performed comprehensive bioinformatics on high-dimensional TCR Vß sequencing data from published and unpublished MS and healthy donors (HD) studies. We evaluated repertoire polarization, clone distribution, shared CDR3 amino acid sequences (CDR3s-a.a.) across repertoires, clone overlap with public databases, and TCR similarity architecture. FINDINGS: CSF repertoires showed a significantly higher public clones percentage and sequence similarity compared to peripheral blood (PB). On the other hand, we failed to reject the null hypothesis that the repertoire polarization is the same between CSF and PB. One Primary-Progressive MS (PPMS) CSF repertoire differed from the others in terms of TCR similarity architecture. Cluster analysis splits MS from HD. INTERPRETATION: In MS patients, the presence of a physiological barrier, the blood-brain barrier, does not impact clone prevalence and distribution, but impacts public clones, indicating CSF as a more private site. We reported a high Vß sequence similarity in the CSF-TCR architecture in one PPMS. If confirmed it may be an interesting insight into MS progressive inflammatory mechanisms. The clustering of MS repertoires from HD suggests that disease shapes the TCR Vß clonal profile. FUNDING: This study was partly financially supported by the Italian Multiple Sclerosis Foundation (FISM), that contributed to Ballerini-DB data collection (grant #2015 R02).
Assuntos
Líquido Cefalorraquidiano/imunologia , Biologia Computacional/métodos , Esclerose Múltipla/imunologia , Receptores de Antígenos de Linfócitos T/metabolismo , Linfócitos T/imunologia , Adulto , Idoso , Barreira Hematoencefálica , Estudos de Casos e Controles , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/genética , Receptores de Antígenos de Linfócitos T/sangue , Receptores de Antígenos de Linfócitos T/genética , Análise de Sequência de DNA , Adulto JovemRESUMO
B cells are important pathogenic players in multiple sclerosis (MS), but their exact role is not known. We have previously demonstrated that B cells from cerebrospinal fluid (CSF) of MS patients can activate T cells that specifically recognize antigenic determinants (idiotopes) from their B cell receptors (BCRs). The aim of this study was to evaluate whether in silico prediction models could identify antigenic idiotopes of immunoglobulin heavy-chain variable (IGHV) transcriptomes in MS patients. We utilized a previously assembled dataset of CSF IGHV repertoires from MS patients. To guide selection of potential antigenic idiotopes, we used in silico predicted HLA-DR affinity, endosomal processing, as well as transcript frequency from nine MS patients. Idiotopes with predicted low affinity and low likelihood of cathepsins cleavage were inert controls. Peripheral blood mononuclear cells from these patients were stimulated with the selected idiotope peptides in presence of anti-CD40 for 12 h. T cells were then labeled for activation status with anti-CD154 antibodies and CD3+CD4+ T cells phenotyped as memory (CD45RO+) or naïve (CD45RO-), with potential for brain migration (CXCR3 and/or CCR6 expression). Anti-CD14 and -CD8 were utilized to exclude monocytes and CD8+ T cells. Unstimulated cells or insulin peptides were negative controls, and EBNA-1 peptides or CD3/CD28 beads were positive controls. The mean proportion of responding memory CD4+ T cells from all nine MS patients was significantly higher for idiotope peptides with predicted high HLA-DR affinity and high likelihood of cathepsin cleavage, than toward predicted inert peptides. Responses were mainly observed toward peptides affiliated with the CDR3 region. Activated memory CD4+ T cells expressed the chemokine receptor CCR6, affiliated with a Th17 phenotype and allowing passage into the central nervous system (CNS). This in vitro study suggests that that antigenic properties of BCR idiotopes can be identified in silico using HLA affinity and endosomal processing predictions. It further indicates that MS patients have a memory T cell repertoire capable of recognizing frequent BCR idiotopes found in endogenous CSF, and that these T cells express chemokine receptors allowing them to reach the CSF B cells expressing these idiotopes.
Assuntos
Linfócitos T CD4-Positivos/imunologia , Líquido Cefalorraquidiano/imunologia , Epitopos de Linfócito B/imunologia , Esclerose Múltipla/imunologia , Receptores de Antígenos de Linfócitos B/imunologia , Linfócitos B/fisiologia , Linfócitos T CD8-Positivos/imunologia , Comunicação Celular , Humanos , Memória Imunológica , Receptores CCR6/análiseRESUMO
Animal studies have shown endocrine changes after levetiracetam treatment. The present study investigated reproductive and sexual function in patients with epilepsy (aged 18-45) treated with levetiracetam (LEV: 30 men/26 women), carbamazepine (CBZ: 63 men/30 women), or lamotrigine (LTG: 37 men/40 women) monotherapy and in healthy controls (36 men/44 women). In women, no endocrine changes were observed during LEV treatment, whereas steroid hormone-binding globulin levels were greater and progesterone levels lower in women using CBZ. Dehydroepiandrosterone sulfate levels were higher and androstenedione levels lower in LTG-treated women. Arizona Sexual Experience Scale scores, which were significantly lower in females using LTG or LEV, suggesting they have better sexual function than CBZ users and controls. In men, no drug-specific hormonal pattern was observed after LEV treatment. Male patients in all treatment groups had lower androstenedione and free testosterone. Those using CBZ had lower free androgen indices and dehydroepiandrosterone sulfate levels, and higher steroid hormone-binding globulin, follicle-stimulating hormone, and luteinizing hormone levels. Arizona Sexual Experience Scale scores for men were similar in all groups. In conclusion, LEV treatment apparently has no drug-specific sexual or endocrine side effects in men or women in this age group.
Assuntos
Anticonvulsivantes/uso terapêutico , Epilepsia/tratamento farmacológico , Epilepsia/fisiopatologia , Hormônios Esteroides Gonadais/metabolismo , Adolescente , Adulto , Fatores Etários , Carbamazepina/uso terapêutico , Estudos Transversais , Feminino , Gonadotropinas/sangue , Humanos , Imunoensaio/métodos , Lamotrigina , Levetiracetam , Masculino , Pessoa de Meia-Idade , Piracetam/análogos & derivados , Piracetam/uso terapêutico , Fatores Sexuais , Inquéritos e Questionários , Testosterona/sangue , Triazinas/uso terapêutico , Adulto JovemRESUMO
INTRODUCTION: Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system. The latest development of B-cell depletion by anti-CD20 monoclonal antibodies has been a large step forward in the treatment of this devastating disease. AREAS COVERED: In this manuscript, we review mechanisms of action, efficacy, safety, and tolerance of anti-CD20 therapies for MS, including rituximab, ocrelizumab, and ofatumumab. EXPERT OPINION: B-cell depletion efficiently suppresses acute inflammatory disease activity in relapsing-remitting MS (RRMS), and may slowdown progression in primary progressive MS (PPMS). The treatment is generally well tolerated, with manageable adverse events related to infusion reactions and infections. Ocrelizumab, a humanized anti-CD20 monoclonal antibody, is the first therapy to be approved for the treatment of both RRMS and PPMS.
Assuntos
Linfócitos B/efeitos dos fármacos , Fatores Imunológicos/uso terapêutico , Esclerose Múltipla/terapia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Monoclonais Humanizados/uso terapêutico , Antígenos CD20/imunologia , Linfócitos B/imunologia , Progressão da Doença , Humanos , Esclerose Múltipla/imunologia , Rituximab/uso terapêuticoRESUMO
In multiple sclerosis (MS), B cells are trafficking across the blood-brain barrier, but it is not known how this relates to the synthesis of oligoclonal IgG. We used quantitative mass spectrometry of oligoclonal bands and high-throughput sequencing of immunoglobulin heavy-chain variable transcripts to study the longitudinal B cell response in the cerebrospinal fluid (CSF) and blood of two MS patients. Twenty of 22 (91%) and 25 of 28 (89%) of oligoclonal band peptides persisted in samples collected 18â¯months apart, in spite of a dynamic exchange across the blood-CSF barrier of B lineage cells connecting to oligoclonal IgG.
Assuntos
Subpopulações de Linfócitos B/imunologia , Imunoglobulina G/líquido cefalorraquidiano , Esclerose Múltipla Recidivante-Remitente/líquido cefalorraquidiano , Bandas Oligoclonais/líquido cefalorraquidiano , Adulto , Sequência de Aminoácidos , Barreira Hematoencefálica , Linhagem da Célula , Feminino , Seguimentos , Rearranjo Gênico do Linfócito B , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/genética , Imunoglobulina G/imunologia , Região Variável de Imunoglobulina/genética , Fatores Imunológicos/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Esclerose Múltipla Recidivante-Remitente/imunologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcriptoma , Adulto JovemRESUMO
The presence of nicotinic and muscarinic receptors suggests the occurrence of cholinergic neurotransmission in white matter; however no quantitative information exists on acetylcholine formation and breakdown in white matter. We compared white structures of pig brain (fimbria, corpus callosum, pyramidal tracts, and occipital white matter) to gray structures (temporal, parietal and cerebellar cortices, hippocampus, and caudate) and found that sodium-dependent, high-affinity choline uptake in white structures was 25-31% of that in hippocampus. White matter choline acetyltransferase activity was 10-50% of the hippocampal value; the highest activity was found in fimbria. Acetylcholine esterase activity in white structures was 20-25% of that in hippocampus. The caudate, which is rich in cholinergic interneurons, gave values for all three parameters that were 2.8-4 times higher than in hippocampus. The results suggest a certain capacity for cholinergic neurotransmission in central nervous white matter. The white matter activity of pyruvate dehydrogenase, which provides acetyl-CoA for acetylcholine synthesis, ranged between 33 and 50% of the hippocampal activity; the activity in the caudate was similar to that in hippocampus and the other gray structures, which was true also for other enzymes of glucose metabolism: hexokinase, phosphoglucomutase, and glucose-6-phosphate dehydrogenase. Acetylcholine esterase activity in white matter was inhibited by the nerve agent soman, which may help explain the reported deleterious effect of soman on white matter. Further, this finding suggests that acetylcholine esterase inhibitors used in Alzheimer's disease may have an effect in white matter.
Assuntos
Acetilcolina/biossíntese , Encéfalo/enzimologia , Fibras Colinérgicas/enzimologia , Proteínas de Membrana Transportadoras/metabolismo , Fibras Nervosas Mielinizadas/enzimologia , Acetilcoenzima A/análise , Acetilcoenzima A/metabolismo , Acetilcolinesterase/análise , Acetilcolinesterase/metabolismo , Animais , Encéfalo/citologia , Mapeamento Encefálico , Colina/análise , Colina/metabolismo , Colina O-Acetiltransferase/análise , Colina O-Acetiltransferase/metabolismo , Fibras Colinérgicas/efeitos dos fármacos , Fibras Colinérgicas/ultraestrutura , Inibidores da Colinesterase/farmacologia , Feminino , Glucose/metabolismo , Imuno-Histoquímica , Interneurônios/metabolismo , Masculino , Proteínas de Membrana Transportadoras/análise , Fibras Nervosas Mielinizadas/efeitos dos fármacos , Fibras Nervosas Mielinizadas/ultraestrutura , Complexo Piruvato Desidrogenase/análise , Complexo Piruvato Desidrogenase/metabolismo , Soman/farmacologia , Sus scrofa , Degeneração Walleriana/induzido quimicamente , Degeneração Walleriana/enzimologia , Degeneração Walleriana/fisiopatologiaRESUMO
BACKGROUND: Trousseau's syndrom may be defined as a symptomatic state of venous and/or arterial hypercoagulability in patients with known or undiscovered cancer. It represents a clinical continuum from a subclinical prothrombotic state to disseminated intravascular coagulation (DIC), venous thromboembolism (VTE) and non-bacterial thrombotic endocarditis (NBTE). MATERIAL AND METHODS: A 58-year-old woman with bilateral pulmonary embolism and ischemic infarctions of the heart, brain, liver and kidneys is presented. Literature published before November 2005 was retrieved from a systematic MEDLINE search. The case is discussed in the light of relevant literature. RESULTS AND INTERPRETATION: Our patient developed Trousseau's syndrom due to a mucinous ventricular adenocarcinoma. Low molecular weight heparin should be used as treatment and secondary prophylaxis in patients with cancer and VTE. Dalteparin reduces the risk of recurrent thromboembolism more effectively than coumarin derivatives, and it is not associated with a greater risk of bleeding. It may improve survival in patients with solid tumours without metastases. There is no consensus regarding treatment of patients with cancer and DIC/NBTE, but dalteparin may be an option.
Assuntos
Acidente Vascular Cerebral , Trombose , Troponina/sangue , Adenocarcinoma Mucinoso/complicações , Adenocarcinoma Mucinoso/diagnóstico , Biomarcadores Tumorais/sangue , Infarto Encefálico/diagnóstico , Infarto Encefálico/etiologia , Diagnóstico Diferencial , Evolução Fatal , Feminino , Humanos , Infarto/diagnóstico , Infarto/etiologia , Rim/irrigação sanguínea , Fígado/irrigação sanguínea , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/etiologia , Embolia Pulmonar/diagnóstico , Embolia Pulmonar/etiologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Síndrome , Trombose/diagnóstico , Trombose/etiologia , Tomografia Computadorizada por Raios XRESUMO
We have previously shown that plasmablasts of the G1m1 allotype of IgG1 are selectively enriched in the cerebrospinal fluid of G1m1/G1m3 heterozygous patients with multiple sclerosis, whereas both allotypes are equally used in neuroborreliosis. Here, we demonstrate a strong preference for the G1m1 allotype in the intrathecal humoral immune responses against measles, rubella, and varicella zoster virus in G1m1/G1m3 heterozygous multiple sclerosis patients. Conversely, intrathecally synthesized varicella zoster virus-specific IgG1 in varicella zoster virus meningoencephalitis comprised both allotypes. This implies that G1m1 B cells are selected to the central nervous system of multiple sclerosis patients regardless of specificity and suggests that an antigen-independent mechanism could drive the intrathecal humoral immune response.
RESUMO
BACKGROUND: B cells may contribute to the immunopathogenesis of multiple sclerosis (MS). Dimethyl fumarate (DMF) has recently been shown to reduce the frequency of memory B cells in blood, but it is not known whether the drug influences the cellular composition in the cerebrospinal fluid (CSF). METHODS: A cross-sectional study examining the cellular composition in blood and cerebrospinal fluid (CSF) from 10 patients treated with DMF and 18 patients receiving other disease modifying drugs or no treatment. RESULTS: Patients treated with DMF had reduced proportions of memory B cells in blood compared to other MS patients (pâ¯=â¯0.0007), and the reduction correlated with treatment duration (rsâ¯=â¯-0.75, pâ¯=â¯0.021). In the CSF, the absolute number of mononuclear cells were significantly lower in DMF-treated patients compared to the other patients (pâ¯=â¯0.023), and there was a disproportionate decrease of plasmablasts (pâ¯=â¯0.031). CONCLUSION: The results of this exploratory study support a B-cell mediated mechanism of action for DMF in both blood and CSF.
Assuntos
Linfócitos B/efeitos dos fármacos , Fumarato de Dimetilo/farmacologia , Imunossupressores/farmacologia , Esclerose Múltipla , Adulto , Estudos Transversais , Fumarato de Dimetilo/administração & dosagem , Feminino , Humanos , Imunossupressores/administração & dosagem , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/tratamento farmacológicoRESUMO
Immunoglobulin gamma (IgG) heavy chain genes are associated with susceptibility to multiple sclerosis (MS) and IgG levels in the cerebrospinal fluid (CSF). However, how these variants are implicated in disease mechanisms remains unknown. Here, we show that proliferating plasmablasts expressing the G1m1 allotype of IgG1 are selectively enriched in CSF of G1m1/G1m3 heterozygous MS patients, whereas plasmablasts expressing either G1m1 or G1m3 are evenly distributed in blood. Moreover, there was a preferential intrathecal synthesis of oligoclonal IgG1 of the G1m1 allotype in heterozygous patients, whereas controls with Lyme neuroborreliosis displayed oligoclonal IgG1 of both allotypes. This points to a disease-specific mechanism involved in B-cell establishment within the central nervous system in MS.