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1.
Clin Immunol ; 230: 108817, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34352391

RESUMO

Many studies have analyzed myelin-reactivity of T cells in multiple sclerosis (MS); however, with conflicting results. In this study we compare methods to determine myelin reactivity of T cells and aim to delineate the cause of inconsistency in the literature. Challenging T cells with myelin antigens we found a significant increase in antigen-reactivity of T cells from patients with MS using an ELISpot-assay, in contrast to a CFSE-dilution assay. Comparing the two assays showed that the myelin-reactive T cells detected in the ELISpot-assay originated primarily from effector memory T cells in contrast to the myelin-reactive T cells of the CFSE-assay representing a population of both naïve, central memory and effector memory T cells. This diversity in T cell populations activated in the two assays likely contribute to the discrepancy found in the literature and encourages thorough considerations when choosing an assay to determine antigen-specificity of T cells in future studies.


Assuntos
Imunoensaio/métodos , Esclerose Múltipla Recidivante-Remitente/imunologia , Proteínas da Mielina/imunologia , Linfócitos T/imunologia , Adulto , Autoantígenos/imunologia , Estudos de Casos e Controles , ELISPOT , Feminino , Fluoresceínas , Corantes Fluorescentes , Humanos , Memória Imunológica , Masculino , Pessoa de Meia-Idade , Proteína Básica da Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Succinimidas , Linfócitos T/classificação , Adulto Jovem
2.
Front Immunol ; 12: 624685, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33679769

RESUMO

Antigen-specific therapy for multiple sclerosis may lead to a more effective therapy by induction of tolerance to a wide range of myelin-derived antigens without hampering the normal surveillance and effector function of the immune system. Numerous attempts to restore tolerance toward myelin-derived antigens have been made over the past decades, both in animal models of multiple sclerosis and in clinical trials for multiple sclerosis patients. In this review, we will give an overview of the current approaches for antigen-specific therapy that are in clinical development for multiple sclerosis as well provide an insight into the challenges for future antigen-specific treatment strategies for multiple sclerosis.


Assuntos
Transferência Adotiva , Dessensibilização Imunológica , Esclerose Múltipla/terapia , Proteínas da Mielina/administração & dosagem , Fragmentos de Peptídeos/administração & dosagem , Vacinação , Vacinas/uso terapêutico , Transferência Adotiva/efeitos adversos , Transferência Adotiva/história , Transferência Adotiva/tendências , Animais , Autoimunidade , Dessensibilização Imunológica/efeitos adversos , Dessensibilização Imunológica/história , Dessensibilização Imunológica/tendências , Difusão de Inovações , Previsões , História do Século XX , História do Século XXI , Humanos , Tolerância Imunológica , Esclerose Múltipla/história , Esclerose Múltipla/imunologia , Esclerose Múltipla/metabolismo , Proteínas da Mielina/efeitos adversos , Proteínas da Mielina/imunologia , Proteínas da Mielina/metabolismo , Fragmentos de Peptídeos/efeitos adversos , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Vacinação/efeitos adversos , Vacinação/história , Vacinação/tendências , Vacinas/efeitos adversos
3.
Cancer Immunol Immunother ; 70(2): 417-429, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32770259

RESUMO

The "macrotrabecular-massive" (MTM) pattern of hepatocellular carcinoma (HCC) has been suggested to represent a distinct HCC subtype and is associated with specific molecular features. Since the immune microenvironment is heterogenous in HCC, it is important to evaluate the immune microenvironment of this novel variant. CMTM6, a key regulator of PD-L1, is an important immunocheckpoint inhibitor. This study aimed to evaluate the prognostic effect of CMTM6/PD-L1 coexpression and its relationship with inflammatory cells in HCC. We analyzed 619 HCC patients and tumors were classified into MTM and non-MTM HCC subtypes. The expression levels of CMTM6 and PD-L1 in tumor and inflammatory cells were evaluated by immunohistochemistry. The density of inflammatory cells in the cancer cell nest was calculated. Tumoral PD-L1 expression and inflammatory cell density were higher in the MTM type than in the non-MTM type. CMTM6-high expression was significantly associated with shorter OS and DFS than CMTM6-low expression in the whole HCC patient population and the MTM HCC patient population. Moreover, MTM HCC patients with CMTM6/PD-L1 coexpression experienced a higher risk of HCC progression and death. In addition, CMTM6/PD-L1 coexpression was shown to be related to a high density of inflammatory cells. Notably, a new immune classification, based on CMTM6/PD-L1 coexpression and inflammatory cells, successfully stratified OS and DFS in MTM HCC. CMTM6/PD-L1 coexpression has an adverse effect on the prognosis of HCC patients, especially MTM HCC patients. Our study provides evidence for the combination of immune status assessment with anti-CMTM6 and anti-PD-L1 therapy in MTM HCC patients.


Assuntos
Antígeno B7-H1/biossíntese , Carcinoma Hepatocelular/imunologia , Neoplasias Hepáticas/imunologia , Proteínas com Domínio MARVEL/imunologia , Proteínas da Mielina/imunologia , Adolescente , Adulto , Idoso , Antígeno B7-H1/imunologia , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Imunofenotipagem , Proteínas com Domínio MARVEL/biossíntese , Masculino , Pessoa de Meia-Idade , Proteínas da Mielina/biossíntese , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
4.
Int Immunopharmacol ; 88: 106864, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32866782

RESUMO

BACKGROUND: The aim of this study was to clarify the association between CMTM6 and PD-L1 expression as well as microenvironment in lung squamous carcinoma (LUSC). MATERIAL AND METHODS: Using Spearman's correlation and Tumor Immune Estimation Resource (TIMER), we analyzed the relationship between CMTM6 and PD-L1 mRNA in LUSC. Immunohistochemistry (IHC) assay was applied to validate the correlation between CMTM6 and PD-L1 protein level in 80 LUSC samples originated from Shandong Provincial Hospital. Then, using The Cancer Genome Atlas (TCGA) database and fisher test, we analyzed the differential mutation genes in high and low CMTM6 expression group. TISIDB was used to explore the distribution of CMTM6 across immune- and molecular-subtypes. TCGA database and Gene Set variation analysis (GSVA) were used to analyze the relationship between CMTM6 and immune genes, immune related pathways. RESULT: Positive correlation between CMTM6 and PD-L1 in mRNA and protein level was found in LUSC patients. More gene mutations were found in CMTM6 high expression group compared with low expression group. Meanwhile, we also found the correlation between CMTM6 expression and molecular subtypes, immune genes, immune related pathways. Furthermore, our result revealed that B cells memory, T cells memory testing, T cells folicular helper, macrophages M0, macrophages M1 and neutrophils varied significantly between patients with CMTM6 high and low expression group. Finally, we found that CMTM6 expression was positively related to CD8 + T cell, macrophage, neutrophil and dendtritic cell (all, P < 0.05) and negatively related to CD4 + T cell (P = 0.018). CONCLUSION: CMTM6 is positively associated with PD-L1 expression and correlates with infiltration of immune cells in microenvironment of lung squamous carcinoma.


Assuntos
Antígeno B7-H1/biossíntese , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/imunologia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/imunologia , Linfócitos do Interstício Tumoral/imunologia , Proteínas com Domínio MARVEL/imunologia , Proteínas da Mielina/imunologia , Idoso , Antígeno B7-H1/genética , Carcinoma de Células Escamosas/patologia , Bases de Dados Genéticas , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/imunologia , Humanos , Neoplasias Pulmonares/patologia , Proteínas com Domínio MARVEL/genética , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas da Mielina/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
5.
J Neurol Neurosurg Psychiatry ; 90(9): 1021-1026, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31118222

RESUMO

OBJECTIVES: To re-evaluate serum samples from our 2007 cohort of patients with single-episode isolated ON (SION), recurrent isolated ON (RION), chronic relapsing inflammatory optic neuropathy (CRION), multiple sclerosis-associated ON (MSON) and neuromyelitis optica (NMO). METHODS: We re-screened 103/114 patients with available serum on live cell-based assays (CBA) for aquaporin-4 (AQP4)-M23-IgG and myelin-oligodendrocyte glycoprotein (MOG)-α1-IgG. Further testing included oligoclonal bands, serum levels of glial fibrillar acidic and neurofilament proteins and S100B. We show the impact of updated serology on these patients. RESULTS: Reanalysis of our original cohort revealed that AQP4-IgG seropositivity increased from 56% to 75% for NMO, 5% to 22% for CRION, 6% to 7% for RION, 0% to 7% for MSON and 5% to 6% for SION. MOG-IgG1 was identified in 25% of RION, 25% of CRION, 10% of SION, 0% of MSON and 0% of NMO. As a result, patients have been reclassified incorporating their autoantibody status. Presenting visual acuity was significantly worse in patients who were AQP4-IgG seropositive (p=0.034), but there was no relationship between antibody seropositivity and either ON relapse rate or visual acuity outcome. CONCLUSIONS: The number of patients with seronegative CRION and RION has decreased due to improved detection of autoantibodies over the past decade. It remains essential that the clinical phenotype guides both antibody testing and clinical management. Careful monitoring of the disease course is key when considering whether to treat with prophylactic immune suppression.


Assuntos
Aquaporina 4/imunologia , Autoanticorpos/imunologia , Proteínas Ligadas por GPI/imunologia , Proteínas da Mielina/imunologia , Neurite Óptica/imunologia , Adolescente , Adulto , Idoso , Aquaporina 4/sangue , Autoanticorpos/sangue , Feminino , Seguimentos , Proteínas Ligadas por GPI/sangue , Proteína Glial Fibrilar Ácida/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/imunologia , Proteínas da Mielina/sangue , Proteínas de Neurofilamentos/sangue , Neuromielite Óptica/imunologia , Neurite Óptica/etiologia , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Adulto Jovem
6.
J Neuroimmunol ; 333: 476953, 2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31108399

RESUMO

Specific neutralization of the pathogenic autoimmune cells is the ultimate goal in therapy of Multiple Sclerosis (MS). However, the pathogenic autoimmunity in MS, can be directed against several major target antigens, and therefore targeting pathogenic T-cells directed against a single target antigen is unlikely to be effective. To overcome this multiplicity and the potential complexity of pathogenic autoreactivities in MS, we have put forward the concept of concomitant multi-antigen/multi-epitope targeting as, a conceivably more effective approach to immunotherapy of MS. We constructed an (Experimental Autoimmune Encephalomeylitis (EAE)/MS-related synthetic human Target Autoantigen Gene (MS-shMultiTAG) designed to encode in tandem only EAE/MS related epitopes of all known encephalitogenic proteins. The MS-related protein product (designated Y-MSPc) was immunofunctional and upon tolerogenic administration, it effectively suppressed and reversed EAE induced by a single encephalitogenic protein. Furthermore, Y-MSPc also fully abrogated the development of "complex EAE" induced by a mixture of five encephalitogenic T-cell lines, each specific for a different encephalitogenic epitope of MBP, MOG, PLP, MOBP and OSP. Strikingly, Y-MSPc was consistently more effective than treatment with the single disease-specific peptide or with the peptide cocktail, both in suppressing the development of "classical" or "complex" EAE and in ameliorating ongoing disease. Overall, the modulation of EAE by Y-MSPc was associated with anergizing the pathogenic autoreactive T-cells, downregulation of Th1/Th17 cytokine secretion and upregulation of TGF-ß secretion. Moreover, we show that both suppression and treatment of ongoing EAE by tolerogenic administration of Y-MSPc is associated also with a remarkable increase in a unique subset of dendritic-cells (DCs), CD11c+CD11b+Gr1+-myeloid derived DCs in both spleen and CNS of treated mice. These DCs, which are with strong immunoregulatory characteristics and are functional in down-modulation of MS-like-disease displayed increased production of IL-4, IL-10 and TGF-ß and low IL-12. Functionally, these myeloid DCs suppress the in-vitro proliferation of myelin-specific T-cells and more importantly, the cells were functional in-vivo, as their adoptive transfer into EAE induced mice resulted in strong suppression of the disease, associated with a remarkable induction of CD4 + FoxP3+ regulatory cells. These results, which highlight the efficacy of "multi-epitope-targeting" agent in induction of functional regulatory CD11c+CD11b+Gr1+myeloid DCs, further indicate the potential role of these DCs in maintaining peripheral tolerance and their involvement in downregulation of MS-like-disease.


Assuntos
Células Dendríticas/fisiologia , Encefalomielite Autoimune Experimental/terapia , Proteínas da Mielina/uso terapêutico , Células Mieloides/fisiologia , Transferência Adotiva , Sequência de Aminoácidos , Animais , Antígenos Ly/análise , Antígenos CD11/análise , Antígeno CD11b/análise , Sistema Nervoso Central/imunologia , Sistema Nervoso Central/patologia , Citocinas/biossíntese , Citocinas/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Epitopos/imunologia , Feminino , Tolerância Imunológica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos , Proteínas da Mielina/imunologia , Proteínas da Mielina/fisiologia , Fragmentos de Peptídeos/imunologia , Proteínas Recombinantes/uso terapêutico , Baço/imunologia , Baço/patologia , Especificidade do Receptor de Antígeno de Linfócitos T , Linfócitos T Citotóxicos/imunologia
7.
Rheumatology (Oxford) ; 58(5): 908-913, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30265368

RESUMO

OBJECTIVES: To determine frequency and syndrome specificity of novel and known nervous system (NS)-directed antibodies in a large, unbiased cohort of SLE patients in the Swiss SLE Cohort Study. METHODS: This retrospective pilot study included 174 patients in a cross-sectional and 102 in a longitudinal study. Antibodies against 12 NS antigens [myelin oligodendrocyte glycoprotein (MOG), neurofascin 186 (NF186), aquaporin-4 (AQP4), N-methyl-D-aspartate receptor (subunit NR1) (NMDAR-NR1), α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (subunits 1 and 2) (AMPAR1/2), gamma-aminobutyric acid B receptor (subunits B1 and B2) (GABABR1/2), glutamate decarboxylase 65 (GAD65), glycine receptor (GlyR), contactin-associated protein-like 2 (CASPR2), leucine-rich glioma-inactivated 1 (LGI1), metabotropic glutamate receptor 5 (mGluR5) and dipeptidyl-peptidase-like protein 6 (DPPX)] were screened with validated cell-based assays and correlated with clinical and diagnostic findings. RESULTS: Twenty-three of one hundred and seventy-four (13.2%) patients harboured antibodies against MOG (n = 14), NF186 (n = 6), GAD65 (n = 2), AQP4 and GlyR (n = 1). Anti-MOG antibodies were most frequently found in the cohort (8%). Thirteen of the anti-NS antibody-positive patients showed clinical symptoms of NS involvement, a subgroup of which (n = 8) resembled the syndrome associated with the antibody. Nine patients harboured antibodies without neurological symptoms and one patient was lost to follow-up. The frequency of NPSLE was significantly higher in the anti-NS antibody-positive patients (13/23, 56.5%: MOG 6/14, 42.9%; NF186 5/6, 83.3%; GAD65 2/2, 100%; AQP4/GlyR 0/1, 0%) compared with the antibody-negative cohort (21/151, 13.9%) (chi-square test, P < 0.0001). CONCLUSION: Anti-NS antibodies, most prevalently anti-MOG antibodies, are significantly associated with NPSLE and manifest with the distinct neurological syndrome associated with the antibody in a subgroup. Follow-up studies in large, independent cohorts will reveal whether these anti-NS antibodies could serve as a diagnostic and prognostic biomarker for NPSLE and enable tailored treatment decisions in this challenging and diverse patient cohort.


Assuntos
Antígenos/imunologia , Autoanticorpos/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Proteínas da Mielina/imunologia , Proteínas do Tecido Nervoso/imunologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Glicoproteína Mielina-Oligodendrócito/imunologia , Projetos Piloto , Estudos Retrospectivos , Suíça , Adulto Jovem
8.
Microbiol Immunol ; 62(4): 255-268, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29388727

RESUMO

The genome organizer special AT-rich sequence binding protein 1 (SATB1) regulates specific functions through chromatin remodeling in T helper cells. It was recently reported by our team that T cells from SATB1 conditional knockout (SATB1cKO) mice, in which the Satb1 gene is deleted from hematopoietic cells, impair phosphorylation of signaling molecules in response to T cell receptor (TCR) crosslinking. However, in vivo T cell responses upon antigen presentation in the absence of SATB1 remain unclear. In the current study, it was shown that SATB1 modulates T cell antigen responses during the induction and effector phases. Expression of SATB1 was upregulated in response to TCR stimulation, suggesting that SATB1 is important for this antigen response. The role of SATB1 in TCR responses and induced experimental autoimmune encephalomyelitis (EAE) was therefore examined using the myelin oligodendrocyte glycoprotein peptide 35-55 (MOG35-55) and pertussis toxin. SATB1cKO mice were found to be resistant to EAE and had defects in IL-17- and IFN-γ-producing pathogenic T cells. Thus, SATB1 expression appears necessary for T cell function in the induction phase. To examine SATB1 function during the effector phase, a tamoxifen-inducible SATB1 deletion system, SATB1cKO-ER-Cre mice, was used. Encephalitogenic T cells from MOG35-55-immunized SATB1cKO-ER-Cre mice were transferred into healthy mice. Mice that received tamoxifen before the onset of paralysis were resistant to EAE. Furthermore, no disease progression occurred in recipient mice treated with tamoxifen after the onset of EAE. Thus, SATB1 is essential for maintaining TCR responsiveness during the induction and effector phases and may provide a novel therapeutic target for T cell-mediated autoimmune diseases.


Assuntos
Encefalomielite Autoimune Experimental/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Animais , Modelos Animais de Doenças , Progressão da Doença , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/patologia , Proteínas Ligadas por GPI/imunologia , Interferon gama/imunologia , Interleucina-17/imunologia , Proteínas de Ligação à Região de Interação com a Matriz/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas da Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito , Fragmentos de Peptídeos/imunologia , Toxina Pertussis , Linfócitos T/imunologia , Tamoxifeno/farmacologia
9.
Acta Neuropathol Commun ; 5(1): 25, 2017 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-28340598

RESUMO

Intrathecal immunoglobulin G (IgG) synthesis, cerebrospinal fluid (CSF) oligoclonal IgG bands and lesional IgG deposition are seminal features of multiple sclerosis (MS) disease pathology. Both the specific targets and pathogenic effects of MS antibodies remain poorly characterized. We produced IgG1 monoclonal recombinant antibodies (rAbs) from clonally-expanded plasmablasts recovered from MS patient CSF. Among these were a subset of myelin-specific MS rAbs. We examined their immunoreactivity to mouse organotypic cerebellar slices by live binding and evaluated tissue injury in the presence and absence of human complement. Demyelination, glial and neuronal viability, and complement pathway activation were assayed by immunofluorescence microscopy and compared to the effects of an aquaporin-4 water channel (AQP4)-specific rAb derived from a neuromyelitis optica (NMO) patient. MS myelin-specific rAbs bound to discrete surface domains on oligodendrocyte processes and myelinating axons. Myelin-specific MS rAbs initiated complement-dependent cytotoxicity to oligodendrocytes and induced rapid demyelination. Demyelination was accompanied by increased microglia activation; however, the morphology and survival of astrocytes, oligodendrocyte progenitors and neurons remained unaffected. In contrast, NMO AQP4-specific rAb initiated complement-dependent astrocyte damage, followed by sequential loss of oligodendrocytes, demyelination, microglia activation and neuronal death. Myelin-specific MS antibodies cause oligodendrocyte loss and demyelination in organotypic cerebellar slices, which are distinct from AQP4-targeted pathology, and display seminal features of active MS lesions. Myelin-specific antibodies may play an active role in MS lesion formation through complement-dependent mechanisms.


Assuntos
Proteínas do Sistema Complemento/imunologia , Imunoglobulina G/imunologia , Esclerose Múltipla/imunologia , Proteínas da Mielina/imunologia , Oligodendroglia/imunologia , Oligodendroglia/patologia , Animais , Astrócitos/imunologia , Astrócitos/patologia , Morte Celular , Cerebelo/imunologia , Cerebelo/patologia , Proteínas do Sistema Complemento/metabolismo , Humanos , Imunoglobulina G/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microglia/imunologia , Microglia/patologia , Esclerose Múltipla/patologia , Neurônios/imunologia , Neurônios/patologia , Neurite Óptica/imunologia , Neurite Óptica/patologia , Plasmócitos/imunologia , Proteínas Recombinantes/metabolismo , Técnicas de Cultura de Tecidos
10.
Immunol Lett ; 183: 79-85, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28189601

RESUMO

Multiple sclerosis is an autoimmune disease caused by the destruction of the myelin sheath in the central nervous system. The major target molecules for the immune response are the myelin basic protein, myelin oligodendrocyte glycoprotein and proteolipid protein but the aetiology of the disease is as yet poorly understood. The HLA Class II allele DRB1*1501 in particular as well as DRB5*0101 and the expression of human endogenous retroviral envelope proteins have been linked to multiple sclerosis but the molecular mechanisms relating these remain to be elucidated. We hypothesised that cross-reactive peptide epitopes in retroviral envelope proteins and myelin proteins that can be presented by the two Class II DR molecules may play a role in initiating multiple sclerosis. Sequence homologies between retroviral envelope and myelin proteins and in silico predictions of peptides derived from them that are able to bind to the two Class II alleles were examined to test the hypothesis. The results support the hypothesis that molecular mimicry in peptide epitopes from envelope proteins of the HERV-W family of endogenous retroviruses and myelin proteins is possible and could potentially trigger multiple sclerosis. Mimicry between syncytin-1, a HERV-W envelope protein that is expressed during placentation, and myelin proteins may also explain the higher prevalence of multiple sclerosis in women. Experiments to test the ability of the identified peptide epitopes to activate TH cells are required to confirm the present findings.


Assuntos
Retrovirus Endógenos/metabolismo , Mimetismo Molecular , Esclerose Múltipla/etiologia , Esclerose Múltipla/metabolismo , Proteínas da Mielina/metabolismo , Proteínas do Envelope Viral/metabolismo , Sequência de Aminoácidos , Biologia Computacional/métodos , Retrovirus Endógenos/química , Feminino , Produtos do Gene env/química , Produtos do Gene env/imunologia , Produtos do Gene env/metabolismo , Antígeno HLA-DR2/imunologia , Antígeno HLA-DR2/metabolismo , Humanos , Masculino , Esclerose Múltipla/patologia , Proteína Básica da Mielina/química , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Proteínas da Mielina/química , Proteínas da Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito/química , Glicoproteína Mielina-Oligodendrócito/imunologia , Glicoproteína Mielina-Oligodendrócito/metabolismo , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/imunologia , Fragmentos de Peptídeos/metabolismo , Proteínas da Gravidez/química , Proteínas da Gravidez/imunologia , Proteínas da Gravidez/metabolismo , Ligação Proteica , Homologia de Sequência de Aminoácidos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Proteínas do Envelope Viral/química
12.
Eur J Immunol ; 46(9): 2247-59, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27334749

RESUMO

T-cell polyspecificity, predicting that individual T cells recognize a continuum of related ligands, implies that multiple antigens can tolerize T cells specific for a given self-antigen. We previously showed in C57BL/6 mice that part of the CD4(+) T-cell repertoire specific for myelin oligodendrocyte glycoprotein (MOG) 35-55 also recognizes the neuronal antigen neurofilament medium (NF-M) 15-35. Such bi-specific CD4(+) T cells are frequent and produce inflammatory cytokines after stimulation. Since T cells recognizing two self-antigens would be expected to be tolerized more efficiently, this finding prompted us to study how polyspecificity impacts tolerance. We found that similar to MOG, NF-M is expressed in the thymus by medullary thymic epithelial cells, a tolerogenic population. Nevertheless, the frequency, phenotype, and capacity to transfer experimental autoimmune encephalomyelitis (EAE) of MOG35-55 -reactive CD4(+) T cells were increased in MOG-deficient but not in NF-M-deficient mice. We found that presentation of NF-M15-35 by I-A(b) on dendritic cells is of short duration, suggesting unstable MHC class II binding. Consistently, introducing an MHC-anchoring residue into NF-M15-35 (NF-M15-35 T20Y) increased its immunogenicity, activating a repertoire able to induce EAE. Our results show that in C57BL/6 mice bi-specific encephalitogenic T cells manage to escape tolerization due to inefficient exposure to two self-antigens.


Assuntos
Autoantígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Tolerância Imunológica , Proteínas da Mielina/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Neurônios/imunologia , Animais , Citocinas/biossíntese , Encefalomielite Autoimune Experimental/genética , Encefalomielite Autoimune Experimental/imunologia , Encefalomielite Autoimune Experimental/patologia , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Expressão Gênica , Ativação Linfocitária/imunologia , Camundongos , Camundongos Knockout , Glicoproteína Mielina-Oligodendrócito/genética , Proteínas de Neurofilamentos/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Especificidade do Receptor de Antígeno de Linfócitos T/genética , Especificidade do Receptor de Antígeno de Linfócitos T/imunologia , Timo/imunologia , Timo/metabolismo
13.
Curr Pharm Des ; 22(6): 728-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26635269

RESUMO

In the injured adult mammalian central nervous system (CNS), the failure of axonal regeneration is thought to be attributed, at least in part, to various myelin-associated inhibitors (MAIs), such as Nogo, myelinassociated glycoprotein (MAG), and oligodendrocyte-myelin glycoprotein (OMgp) around the damaged site. Interestingly, these three structurally different inhibitors share two common receptors, Nogo-66 receptor (NgR) and paired immunoglobulin-like receptor B (PirB), and transduce the inhibitory signal into neurons via their complex combinant and co-receptors, such as p75 neurotrophin receptor (p75NTR), Nogo receptor-interacting protein 1 (LINGO-1), and TROY. Accordingly, targeting of the whole myelin or just portions by immunization has been proved to be neuroprotective and is able to promote regeneration in the injured spinal cords. In the past few years, vaccine approaches were initially achieved and could induce the production of antibodies against inhibitors in myelin to block the inhibitory effects and promote functional recovery in spinal cord injury (SCI) models by immunizing with MAIs, such as purified myelin, spinal cord homogenates, or their receptors with the concept of protective autoimmunity formulated. However, for safety consideration, further work is necessary before the immunotherapy strategies can be adopted to treat human injured spinal cords.


Assuntos
Imunoterapia/métodos , Terapia de Alvo Molecular/métodos , Proteínas da Mielina/imunologia , Receptores de Superfície Celular/imunologia , Traumatismos da Medula Espinal/terapia , Vacinas Sintéticas/uso terapêutico , Anticorpos Neutralizantes/imunologia , Humanos , Traumatismos da Medula Espinal/imunologia , Regeneração da Medula Espinal/imunologia
14.
J Alzheimers Dis ; 48(1): 115-21, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26401933

RESUMO

BACKGROUND: Alzheimer's disease (AD) is known to exhibit well characterized pathologies including the extracellular accumulation of amyloid plaques, intra-axonal presence of neurofibrillary tangles, and glial hypertrophy. Nevertheless, the nature of myelin pathology in AD has not been well studied. Recent studies on animal models of AD, however, revealed focal demyelination within amyloid-ß plaques in hippocampus. OBJECTIVES: In a view of this finding, we decided to assess humoral response against proteins of myelin sheath in AD, in the hope of identifying early biomarkers of memory loss and neuropathological process characteristic of AD. METHODS: We assessed antibodies levels against proteins of the myelin sheath: myelin oligodendrocyte glycoprotein (MOG), myelin basic protein (MBP), myelin-associated glycoprotein (MAG), and proteolipoprotein (PLP) in sera of 26 AD patients and 26 healthy controls, using commercially available ELISA system (Mediagnost, Germany). RESULTS: In the AD patient subgroup, significantly higher titers were observed for all types of assessed IgG autoantibodies compared to healthy control subjects (anti-MOG, anti-MAG, anti-MBP, anti-PLP). The titers of most of the investigated IgM antibodies were also higher in AD patients (p <  0.05), with the exception of anti-MAG IgM antibodies (p >  0.05). CONCLUSION: The study provides the evidence for the significantly increased production of autoantibodies against proteins of myelin sheath in AD. These results can be of importance in the light of emerging data from animal models of AD, indicating early demyelination of hippocampal region. Further studies on larger population are necessary to confirm whether these autoantibodies could serve as early biomarkers of AD in humans.


Assuntos
Anticorpos/metabolismo , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/etiologia , Doenças Autoimunes Desmielinizantes do Sistema Nervoso Central/patologia , Hipocampo/metabolismo , Transtornos da Memória/patologia , Proteínas da Mielina/imunologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/complicações , Biomarcadores/metabolismo , Feminino , Humanos , Masculino , Transtornos da Memória/etiologia , Testes Neuropsicológicos , Escalas de Graduação Psiquiátrica , Estatísticas não Paramétricas
15.
Folia Neuropathol ; 53(2): 128-38, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26216115

RESUMO

Oral tolerance is the natural occurring phenomenon of a decreased immune response to previously fed antigens, which prevents induction of a response to dietary antigens. One of the mechanisms is deletion of T lymphocytes reactive to the fed antigen. Knowing that phenomenon, it seems appropriate to engage this mechanism for treatment of autoimmune diseases. Multiple sclerosis (MS) is an autoimmunological disease which causes neurological impairment in humans. Autoreactive T lymphocytes migrate through the open blood-brain barrier into the central nervous system (CNS), where they recognize myelin antigens as foreign, and induce an inflammatory response against the myelin sheath, which causes demyelination and even axonal loss. Experimental allergic encephalomyelitis (EAE), an animal model of MS, resembles the autoimmunological aspect of the disease. We used a broad spectrum of myelin antigens to induce EAE, and also to induce oral tolerance by giving myelin epitopes intragastrically to rats. The aim of our study was to evaluate whether pig spinal cord hydrolysate given intragastrically is able to evoke oral tolerance in rats with an animal model of MS - EAE. In our experiments we fed female Lewis rats with pig spinal cord hydrolysate at doses of 5, 20 and 100 mg per kg of body weight. We observed diminished clinical symptoms of ongoing EAE in rats fed with all doses of pig spinal cord hydrolysate. In the histopathological study, intensity of the inflammatory process in spinal cord was similar in rats not fed with EAE and in rats fed with lower doses of pig spinal cord hydrolysate. In animals fed with the highest dose of pig spinal cord hydrolysate, intensification of the inflammatory response was observed. These results were confirmed by morphometric evaluations. We found that feeding animals with preparations containing myelin antigens can reduce EAE symptoms, which may indicate oral tolerance induction, but the obtained results also underline the importance of dose of the orally given antigens, because of the possibility of enhancement of the inflammatory process in the CNS.


Assuntos
Encefalomielite Autoimune Experimental/patologia , Tolerância Imunológica/imunologia , Proteínas da Mielina/imunologia , Administração Oral , Animais , Encefalomielite Autoimune Experimental/imunologia , Feminino , Cobaias , Hidrólise , Proteínas da Mielina/farmacologia , Ratos , Ratos Endogâmicos Lew , Suínos
19.
Rev Neurol ; 58(10): 455-64, 2014 May 16.
Artigo em Espanhol | MEDLINE | ID: mdl-24819942

RESUMO

INTRODUCTION: The type of diet has been related with the inflammatory process that forms part of multiple sclerosis. In recent years, different lines of research have generated a large body of knowledge about the role played by diet in the pathogenesis of multiple sclerosis. AIM: To conduct a critical examination of the evidence suggesting the existence of a relationship between different types of diets and foods and multiple sclerosis. DEVELOPMENT: The work includes an update of the most significant studies that have analysed the role played by diet in the pathogenesis and treatment of multiple sclerosis. In order to explore the association between diet and the risk of multiple sclerosis, the authors examined the currently available evidence, which ranged from observation-based studies to intervention studies. CONCLUSIONS: Further research on nutrition as a risk factor is needed, as it could be related with the disease and controlling it could lead to a significant reduction in the incidence or progression of the disease.


TITLE: Dieta y esclerosis multiple.Introduccion. El tipo de dieta se ha relacionado con el proceso inflamatorio que forma parte de la esclerosis multiple (EM). En los ultimos años, distintas lineas de investigacion han generado una gran cantidad de conocimiento sobre la participacion de la dieta en la patogenesis de la EM. Objetivo. Elucidar de modo critico las evidencias que relacionan distintos tipos de dietas y alimentos con la EM. Desarrollo. Se incluye una actualizacion de los estudios publicados mas significativos que han analizado el papel de la dieta en la patogenesis y en el tratamiento de la EM. Para explorar la asociacion entre la dieta y el riesgo de EM se ha revisado la evidencia disponible hasta el momento, pasando por estudios observacionales hasta terminar con estudios de intervencion. Conclusiones. Se necesita mas investigacion sobre la nutricion como factor de riesgo, ya que podria tener relacion con la enfermedad, y el control de esta podria llevar a una disminucion significativa de la incidencia o progresion de la patologia.


Assuntos
Dieta/efeitos adversos , Esclerose Múltipla/dietoterapia , Esclerose Múltipla/etiologia , Consumo de Bebidas Alcoólicas/efeitos adversos , Animais , Antioxidantes/uso terapêutico , Butirofilinas , Restrição Calórica , Bovinos , Dieta com Restrição de Gorduras , Gorduras na Dieta/efeitos adversos , Encefalomielite Autoimune Experimental/dietoterapia , Europa (Continente)/epidemiologia , Fadiga/prevenção & controle , Ácidos Graxos/efeitos adversos , Óleos de Peixe/uso terapêutico , Proteínas Ligadas por GPI/imunologia , Humanos , Inflamação , Glicoproteínas de Membrana/efeitos adversos , Glicoproteínas de Membrana/imunologia , Camundongos , Leite/efeitos adversos , Leite Humano , Modelos Biológicos , Mimetismo Molecular , Esclerose Múltipla/epidemiologia , Proteínas da Mielina/imunologia , Estudos Observacionais como Assunto , Azeite de Oliva , Óleos de Plantas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Vitaminas/uso terapêutico
20.
Hum Mol Genet ; 23(16): 4187-200, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24667415

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal, neurodegenerative disorder in which motor neurons in the spinal cord and motor cortex degenerate. Although the majority of ALS cases are sporadic, mutations in Cu-Zn superoxide dismutase-1 (SOD1) are causative for 10-20% of familial ALS (fALS), and recent findings show that a hexanucleotide repeat expansion in the C9ORF72 gene may account for >30% of fALS cases in Europe. SOD1(G93A) transgenic mice have a phenotype and pathology similar to human ALS. In both ALS patients and SOD1(G93A) mice, the first pathological features of disease manifest at the neuromuscular junction, where significant denervation occurs prior to motor neuron degeneration. Strategies aimed at preventing or delaying denervation may therefore be of benefit in ALS. In this study, we show that Nogo-A levels increase in muscle fibres of SOD1(G93A) mice along with the elevation of markers of neuromuscular dysfunction (CHRNA1/MUSK). Symptomatic treatment of SOD1(G93A) mice from 70 days of age with an anti-Nogo-A antibody (GSK577548) significantly improves hindlimb muscle innervation at 90 days, a late symptomatic stage of disease, resulting in increased muscle force and motor unit survival and a significant increase in motor neuron survival. However, not all aspects of this improvement in anti-Nogo-A antibody-treated SOD1(G93A) mice were maintained at end-stage disease. These results show that treatment with anti-Nogo-A antibody significantly improves neuromuscular function in the SOD1(G93A) mouse model of ALS, at least during the earlier stages of disease and suggest that pharmacological inhibition of Nogo-A may be a disease-modifying approach in ALS.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Anticorpos/uso terapêutico , Proteínas da Mielina/imunologia , Superóxido Dismutase/genética , Esclerose Lateral Amiotrófica/patologia , Animais , Anticorpos/imunologia , Modelos Animais de Doenças , Progressão da Doença , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios Motores/patologia , Fibras Musculares de Contração Lenta/metabolismo , Proteínas da Mielina/metabolismo , Proteínas Nogo , Superóxido Dismutase-1
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