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1.
Mult Scler Relat Disord ; 87: 105664, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38735204

RESUMO

BACKGROUND: Natalizumab is an effective treatment for relapsing multiple sclerosis (MS). During therapy, individuals are at increased risk of developing progressive multifocal leukoencephalopathy (PML). So far, the relevant reservoir for PML-type JC polyomavirus (JCV) remains elusive. We here tested if the detection of JCV-DNA in stool of persons with MS treated with natalizumab could be a future tool for PML risk assessment. METHODS: The presence of JCV-DNA in stool, urine, and whole blood of MS patients treated with natalizumab and known serum anti-JCV antibodies index values (IV) was studied. Different DNA extraction methods, real-time (RT) and droplet digital (dd) PCR techniques were compared. JCV isolates were screened for PML-associated variants by sequencing. RESULTS: Thirty MS patients treated with natalizumab were screened. For 21 patients, blood, stool, and urine samples were available. These patients were stratified according to their serum anti-JCV antibody IV (high (>1.5, n = 12); medium (1.5-0.9, n = 2); low (<0.9, n = 1); negative (n = 6)). JCV-DNA could not be detected in the whole blood or stool samples. Four urine samples had measurable JCV-DNA, ranging from 1.71×104-1.07×108 international units (IU)/mL detected by RT-PCR, corresponding to 4.62×104-9.85×106 copies/mL measured by ddPCR. All JCV variants were wild-type and derived from patients with high antibody IV. CONCLUSION: Stool-specific DNA extraction methods provided the highest quality of DNA, while the sensitivity of ddPCR and RT- PCR was comparable. Our findings do not support assessing stool samples for PML risk stratification in persons with MS. Further studies are needed to explore where PML-associated viral variants arise.

2.
Neurology ; 101(16): 700-713, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37487750

RESUMO

JC polyomavirus (JCV) establishes an asymptomatic latent and/or persistent infection in most of the adult population. However, in immunocompromised individuals, JCV can cause a symptomatic infection of the brain, foremost progressive multifocal leukoencephalopathy (PML). In the past 2 decades, there has been increasing concern among patients and the medical community because PML was observed as an adverse event in individuals treated with modern (selective) immune suppressive treatments for various immune-mediated diseases, especially multiple sclerosis. It became evident that this devastating complication also needs to be considered beyond the patient populations historically at risk, including those with hematologic malignancies or HIV-infected individuals. We review the clinical presentation of PML, its variants, pathogenesis, and current diagnostic approaches. We further discuss the need to validate JCV-directed interventions and highlight current management strategies based on early diagnosis and restoring JCV-specific cellular immunity, which is crucial for viral clearance and survival. Finally, we discuss the importance of biomarkers for diagnosis and response to therapy, instrumental in defining sensitive study end points for successful clinical trials of curative or preventive therapeutics. Advances in understanding PML pathophysiology, host and viral genetics, and diagnostics in conjunction with novel immunotherapeutic approaches indicate that the time is right to design and perform definitive trials to develop preventive options and curative therapy for JCV-associated diseases.


Assuntos
Vírus JC , Leucoencefalopatia Multifocal Progressiva , Esclerose Múltipla , Adulto , Humanos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/terapia , Encéfalo , Biomarcadores
3.
Artigo em Inglês | MEDLINE | ID: mdl-37094998

RESUMO

BACKGROUND AND OBJECTIVES: The B cell-depleting anti-CD20 antibody ocrelizumab (OCR) effectively reduces MS disease activity and slows disability progression. Given the role of B cells as antigen-presenting cells, the primary goal of this study was to evaluate the effect of OCR on the T-cell receptor repertoire diversity. METHODS: To examine whether OCR substantially alters the molecular diversity of the T-cell receptor repertoire, deep immune repertoire sequencing (RepSeq) of CD4+ and CD8+ T-cell receptor ß-chain variable regions was performed on longitudinal blood samples. The IgM and IgG heavy chain variable region repertoire was also analyzed to characterize the residual B-cell repertoire under OCR treatment. RESULTS: Peripheral blood samples for RepSeq were obtained from 8 patients with relapsing MS enrolled in the OPERA I trial over a period of up to 39 months. Four patients each were treated with OCR or interferon ß1-a during the double-blind period of OPERA I. All patients received OCR during the open-label extension. The diversity of the CD4+/CD8+ T-cell repertoires remained unaffected in OCR-treated patients. The expected OCR-associated B-cell depletion was mirrored by reduced B-cell receptor diversity in peripheral blood and a shift in immunoglobulin gene usage. Despite deep B-cell depletion, longitudinal persistence of clonally related B-cells was observed. DISCUSSION: Our data illustrate that the diversity of CD4+/CD8+ T-cell receptor repertoires remained unaltered in OCR-treated patients with relapsing MS. Persistence of a highly diverse T-cell repertoire suggests that aspects of adaptive immunity remain intact despite extended anti-CD20 therapy. TRIAL REGISTRATION INFORMATION: This is a substudy (BE29353) of the OPERA I (WA21092; NCT01247324) trial. Date of registration, November 23, 2010; first patient enrollment, August 31, 2011.


Assuntos
Esclerose Múltipla , Humanos , Fatores Imunológicos/farmacologia , Anticorpos Monoclonais Humanizados/farmacologia , Recidiva , Receptores de Antígenos de Linfócitos T
4.
J Stroke Cerebrovasc Dis ; 31(12): 106853, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36323167

RESUMO

BACKGROUND: Racial disparities exist in stroke and stroke outcomes. In an ecologic study, using the Home Owners' Loan Corporation (HOLC) "redlining" scores, as indicator of historic racialized lending practices, we hypothesized that census tracts with high historic redlining are associated with higher stroke prevalence. METHODS: Weighted historic redlining scores (HRS) were calculated using the proportion of 1930s HOLC residential security grades contained within 2010 census tract boundaries of Columbus, Ohio. Stroke prevalence (adults >=18) was obtained at the census tract-level from the CDC's 500 Cities Project. Sociodemographic census tract level data (American Community Survey 2014-2018) were considered mediators in the causal association between historic redlining and stroke prevalence and were not controlled for in regression analysis. HRS and stroke prevalence associations were evaluated with and without adjustment for proportion of census tract 65 years and older. RESULTS: Census tracts in the highest quartile of HRS (greater redlining) had 1.73% higher stroke prevalence compared to those in the lowest quartile (95% CI:0.41,3.05) adjusting for proportion 65 years and older. No other interquartile differences were observed. CONCLUSIONS: Historic redlining practices are a form of structural racism that established geographic systems of disadvantage and consequently, poor health outcomes. Our findings demonstrate disparate stroke prevalence by degree of historic redlining in census tracts across Columbus, Ohio.


Assuntos
Características de Residência , Acidente Vascular Cerebral , Adulto , Humanos , Prevalência , Ohio/epidemiologia , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia
5.
BMC Prim Care ; 23(1): 3, 2022 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-35331144

RESUMO

BACKGROUND: The oldest-old (individuals over 90 years) are a fast-growing population. Understanding the perceptions of older people about very old age is the first step towards developing optimal geriatric care for an aging population. This study aimed to explore the potential shift from old age to very old age through the exploration of older people's perception of aging. METHODS: Qualitative study conducted through individual interviews in the homes of older people. We voluntarily chose to include persons a decade under and above 90 years old to explore other factors than age that could participate in the shift from old age to very old age. The sampling was theoretical. We carried out the analyses using an inductive approach based on the phases of grounded theory. The researchers used triangulation. Collection was concluded when theoretical saturation was reached. RESULTS: Fourteen participants were interviewed. The shift from old age to very old age was not based on age but occurred when participants became conscious of the irreversibility of aging and its effects, and when they started living day-by-day, renouncing to any plan in a near future. The transition to very old age seemed to be preceded by a progressive disengagement from non-essentials activities. Participants reported a sensation of progressive social exclusion due to the loss of contemporaries or spouse, the difficulty to connect with younger generations or the absence of relationships in their neighborhood. The last step of life was feared, not because of the idea of death itself but because of the associated suffering and loss of autonomy. CONCLUSION: Precipitating and slowing factors of the shift to very old age were identified to help general practitioners support older patients throughout their life trajectories.


Assuntos
Envelhecimento , Isolamento Social , Idoso , Idoso de 80 Anos ou mais , Humanos , Percepção , Pesquisa Qualitativa
6.
SSM Popul Health ; 14: 100793, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33997243

RESUMO

Structural racism, which is embedded in past and present operations of the U.S. housing market, is a fundamental cause of racial health inequities. We conducted an ecologic study to 1) examine historic redlining in relation to current neighborhood lending discrimination and three key indicators of societal health (mental health, physical health, and infant mortality rate (IMR)) and 2) investigate sustained lending disinvestment as a determinant of current neighborhood health in one of the most hypersegregated metropolitan areas in the United States, Milwaukee, Wisconsin. We calculated weighted historic redlining scores from the proportion of 1930s Home Owners' Loan Corporation residential security grades contained within 2010 census tract boundaries. We combined two lending indicators from 2018 Home Mortgage Disclosure Act data to capture current neighborhood lending discrimination: low lending occurrence and high cost loans (measured via loan rate spread). Using historic redlining score and current lending discrimination, we created a 4-level hierarchical measure of lending trajectory. In Milwaukee neighborhoods, greater historic redlining was associated with current lending discrimination (OR = 1.73, 95%CI: 1.16, 2.58) and increased prevalence of poor physical health (ß = 1.34, 95%CI: 0.40, 2.28) and poor mental health (ß = 1.26, 95%CI: 0.51, 2.01). Historic redlining was not associated with neighborhood IMR (ß = -0.48, 95%CI: -2.12, 1.15). A graded association was observed between lending trajectory and health: neighborhoods with high sustained disinvestment had worse physical and mental health than neighborhoods with high investment (poor physical health: ß = 5.33, 95%CI: 3.05, 7.61; poor mental health: ß = 4.32, 95%CI: 2.44, 6.20). IMR was highest in 'disinvested' neighborhoods (ß = 5.87, 95%CI: 0.52, 11.22). Our findings illustrate ongoing legacies of government sponsored historic redlining. Structural racism, as manifested in historic and current forms of lending disinvestment, predicts poor health in Milwaukee's hypersegregated neighborhoods. We endorse equity focused policies that dismantle and repair the ways racism is entrenched in America's social fabric.

7.
J Neurol ; 268(2): 392-402, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32691236

RESUMO

OBJECTIVE: To study the frequency of neurological symptoms and complications in COVID-19 patients in a systematic review of the literature. METHODS: Relevant studies were identified through electronic explorations of PubMed, medRxiv, and bioRxiv. Besides, three Chinese databases were searched. A snowballing method searching the bibliographies of the retrieved references was applied to identify potentially relevant articles. Articles published within 1 year prior to April 20th, 2020, were screened with no language restriction imposed. Databases were searched for terms related to SARS-CoV-2/COVID-19 and neurological manifestations, using a pre-established protocol registered on the International Prospective Register of Systematic Reviews database (ID: CRD42020187994). RESULTS: A total of 2441 articles were screened for relevant content, of which 92 full-text publications were included in the analyses of neurological manifestations of COVID-19. Headache, dizziness, taste and smell dysfunctions, and impaired consciousness were the most frequently described neurological symptoms, the latter more often among patients with a severe or critical disease course. To date, only smaller cohort studies or single cases have reported cerebrovascular events, seizures, meningoencephalitis, and immune-mediated neurological diseases, not suitable for quantitative analysis. CONCLUSION: The most frequent neurological symptoms reported in association with COVID-19 are non-specific for the infection with SARS-CoV-2. Although SARS-CoV-2 may have the potential to gain direct access to the nervous system, so far, SARS-CoV-2 was detected in the cerebrospinal fluid in two cases only. Standardized international registries are needed to clarify the clinical relevance of the neuropathogenicity of SARS-CoV-2 and to elucidate a possible impact of SARS-CoV-2 infection on common neurological disease, such as Alzheimer's, Parkinson's disease or multiple sclerosis.


Assuntos
COVID-19/complicações , Doenças do Sistema Nervoso/etiologia , Humanos
8.
Front Immunol ; 10: 1564, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354720

RESUMO

Multiple sclerosis (MS) is the most common neurological immune-mediated disease leading to disability in young adults. The outcome of the disease is unpredictable, and over time, neurological disabilities accumulate. Interferon beta-1b was the first drug to be approved in the 1990s for relapsing-remitting MS to modulate the course of the disease. Over the past two decades, the treatment landscape has changed tremendously. Currently, more than a dozen drugs representing 1 substances with different mechanisms of action have been approved (interferon beta preparations, glatiramer acetate, fingolimod, siponimod, mitoxantrone, teriflunomide, dimethyl fumarate, cladribine, alemtuzumab, ocrelizumab, and natalizumab). Ocrelizumab was the first medication to be approved for primary progressive MS. The objective of this review is to present the modes of action of these drugs and their effects on the immunopathogenesis of MS. Each agent's clinical development and potential side effects are discussed.


Assuntos
Imunossupressores/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/terapia , Animais , Humanos , Fatores Imunológicos/imunologia
9.
Curr Opin Neurol ; 32(3): 305-312, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30985373

RESUMO

PURPOSE OF REVIEW: A variety of high-efficacy disease-modifying therapies (DMTs) are available for the treatment of multiple sclerosis (MS). After evaluation and approval by regulatory agencies, DMTs are likely to be administered to patients whose characteristics differ from those enrolled in clinical trials. This may contribute to the emergence of unexpected adverse events observed in the real-world setting. Higher age may be a relevant factor that could change the benefit-risk balance of DMTs, as it may associate with lower efficiency and higher frequency of adverse events. RECENT FINDINGS: The absolute and relative number of patients with MS who reach the age of 55 and higher increases. Growing evidence demonstrates lower efficacy of DMTs in older persons with MS. Specific risks during DMTs for MS, such as the risk of developing progressive multifocal leukoencephalopathy (PML) or the outcome following PML, have been associated with age. It is hypothesized that age-related and therapy-induced alterations to the immune system may have (super)additive effects, resulting in an acceleration of physiological immunosenescence and inflamm-aging. SUMMARY: In this article, we review the risks of high-efficacy DMTs in MS with a specific focus on age-related efficacy and risks, including opportunistic infections, malignancies, and autoimmune reactions.


Assuntos
Fatores Imunológicos/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Humanos , Fatores Imunológicos/uso terapêutico , Infecções/induzido quimicamente , Leucoencefalopatia Multifocal Progressiva/induzido quimicamente , Neoplasias/induzido quimicamente , Fatores de Risco
10.
JCI Insight ; 4(6)2019 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-30747723

RESUMO

B cells are key contributors to chronic autoimmune pathology in multiple sclerosis (MS). Clonally related B cells exist in the cerebrospinal fluid (CSF), meninges, and CNS parenchyma of MS patients. We sought to investigate the presence of clonally related B cells over time by performing Ig heavy chain variable region repertoire sequencing on B cells from longitudinally collected blood and CSF samples of MS patients (n = 10). All patients were untreated at the time of the initial sampling; the majority (n = 7) were treated with immune-modulating therapies 1.2 (±0.3 SD) years later during the second sampling. We found clonal persistence of B cells in the CSF of 5 patients; these B cells were frequently Ig class-switched and CD27+. Specific blood B cell subsets appear to provide input into CNS repertoires over time. We demonstrate complex patterns of clonal B cell persistence in CSF and blood, even in patients on immune-modulating therapy. Our findings support the concept that peripheral B cell activation and CNS-compartmentalized immune mechanisms can in part be therapy resistant.


Assuntos
Linfócitos B/imunologia , Líquido Cefalorraquidiano/imunologia , Esclerose Múltipla/líquido cefalorraquidiano , Esclerose Múltipla/imunologia , Adulto , Subpopulações de Linfócitos B/imunologia , Feminino , Humanos , Região Variável de Imunoglobulina , Ativação Linfocitária , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Adulto Jovem
11.
Ann Neurol ; 84(2): 315-328, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-30014603

RESUMO

OBJECTIVE: Autoantibodies against myelin oligodendrocyte glycoprotein (MOG) occur in a proportion of patients with inflammatory demyelinating diseases of the central nervous system (CNS). We analyzed their pathogenic activity by affinity-purifying these antibodies (Abs) from patients and transferring them to experimental animals. METHODS: Patients with Abs to MOG were identified by cell-based assay. We determined the cross-reactivity to rodent MOG and the recognized MOG epitopes. We produced the correctly folded extracellular domain of MOG and affinity-purified MOG-specific Abs from the blood of patients. These purified Abs were used to stain CNS tissue and transferred in 2 models of experimental autoimmune encephalomyelitis. Animals were analyzed histopathologically. RESULTS: We identified 17 patients with MOG Abs from our outpatient clinic and selected 2 with a cross-reactivity to rodent MOG; both had recurrent optic neuritis. Affinity-purified Abs recognized MOG on transfected cells and stained myelin in tissue sections. The Abs from the 2 patients recognized different epitopes on MOG, the CC' and the FG loop. In both patients, these Abs persisted during our observation period of 2 to 3 years. The anti-MOG Abs from both patients were pathogenic upon intrathecal injection in 2 different rat models. Together with cognate MOG-specific T cells, these Abs enhanced T-cell infiltration; together with myelin basic protein-specific T cells, they induced demyelination associated with deposition of C9neo, resembling a multiple sclerosis type II pathology. INTERPRETATION: MOG-specific Abs affinity purified from patients with inflammatory demyelinating disease induce pathological changes in vivo upon cotransfer with myelin-reactive T cells, suggesting that these Abs are similarly pathogenic in patients. Ann Neurol 2018;84:315-328.


Assuntos
Autoanticorpos/sangue , Encéfalo/metabolismo , Encéfalo/patologia , Glicoproteína Mielina-Oligodendrócito/sangue , Adulto , Idoso , Animais , Encefalomielite Autoimune Experimental/metabolismo , Encefalomielite Autoimune Experimental/patologia , Feminino , Cobaias , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Masculino , Pessoa de Meia-Idade , Ratos , Ratos Endogâmicos Lew , Adulto Jovem
12.
Neuro Oncol ; 19(12): 1618-1627, 2017 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-28521029

RESUMO

BACKGROUND: B-cell survival is regulated through interactions of B-cell-activating factor and a proliferation-inducing ligand with their receptors transmembrane activator and CAML interactor (TACI) and B-cell maturation antigen (BCMA). We evaluated the diagnostic potential of soluble TACI (sTACI) and soluble BCMA (sBCMA) in CSF and serum as biomarkers in primary CNS lymphoma (PCNSL). METHODS: CSF (n = 176) and serum samples (n = 105) from patients with clinically or radiologically suspected PCNSL as well as from control patients were collected prospectively. Levels of sTACI and sBCMA were analyzed by enzyme-linked immunosorbent assay. Additionally, in patients with PCNSL, CSF was analyzed during disease course (time of diagnosis, n = 26; relapse, n = 10; remission, n = 14), and in 2 patients long-term longitudinal analysis was performed. RESULTS: Soluble TACI and sBCMA are significantly increased in patients with PCNSL (sTACI, median: 445 pg/mL; sBCMA, median: 760 pg/mL) compared with control patients (sTACI, median: 0 pg/mL; sBCMA, median: 290 pg/mL). At a cutoff value of 68.4 pg/mL, sTACI shows high sensitivity (87.9%) and specificity (88.3%) for the diagnosis of active PCNSL. Soluble BCMA is less sensitive (72.7%) and specific (71.8%) (cutoff: 460 pg/mL). When both markers are combined, specificity increases, however, at the cost of a lower sensitivity. In serum, both sTACI and sBCMA are not increased in PCNSL patients. Both soluble receptors correlate with clinical course and therapy response. CONCLUSIONS: Our results suggest that sTACI and sBCMA in the CSF are promising new biomarkers for diagnosis and therapy monitoring in PCNSL. However, our findings need to be validated in an independent cohort.


Assuntos
Antígeno de Maturação de Linfócitos B/análise , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/patologia , Linfoma não Hodgkin/patologia , Proteína Transmembrana Ativadora e Interagente do CAML/análise , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Neoplasias do Sistema Nervoso Central/sangue , Neoplasias do Sistema Nervoso Central/líquido cefalorraquidiano , Neoplasias do Sistema Nervoso Central/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Linfoma não Hodgkin/sangue , Linfoma não Hodgkin/líquido cefalorraquidiano , Linfoma não Hodgkin/terapia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Taxa de Sobrevida , Adulto Jovem
13.
J Immunol ; 198(8): 3081-3088, 2017 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-28283566

RESUMO

The BAFF-APRIL system is best known for its control of B cell homeostasis, and it is a target of therapeutic intervention in autoimmune diseases and lymphoma. By analyzing the expression of the three receptors of this system, B cell maturation Ag (BCMA), transmembrane activator and CAML interactor, and BAFF receptor, in sorted human immune cell subsets, we found that BCMA was transcribed in plasmacytoid dendritic cells (pDCs) in both blood and lymphoid tissue. Circulating human pDCs contained BCMA protein without displaying it on the cell surface. After engagement of TLR7/8 or TLR9, BCMA was detected also on the cell surface of pDCs. The display of BCMA on the surface of human pDCs was accompanied by release of soluble BCMA (sBCMA); inhibition of γ-secretase enhanced surface expression of BCMA and reduced the release of sBCMA by pDCs. In contrast with human pDCs, murine pDCs did not express BCMA, not even after TLR9 activation. In this study, we extend the spectrum of BCMA expression to human pDCs. sBCMA derived from pDCs might determine local availability of its high-affinity ligand APRIL, because sBCMA has been shown to function as an APRIL-specific decoy. Further, therapeutic trials targeting BCMA in patients with multiple myeloma should consider possible effects on pDCs.


Assuntos
Antígeno de Maturação de Linfócitos B/imunologia , Células Dendríticas/imunologia , Transdução de Sinais/imunologia , Animais , Receptor do Fator Ativador de Células B/imunologia , Antígeno de Maturação de Linfócitos B/biossíntese , Separação Celular , Células Dendríticas/metabolismo , Ensaio de Imunoadsorção Enzimática , Citometria de Fluxo , Humanos , Camundongos , Reação em Cadeia da Polimerase
14.
Nat Commun ; 6: 7333, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-26065893

RESUMO

Survival of plasma cells is regulated by B-cell maturation antigen (BCMA), a membrane-bound receptor activated by its agonist ligands BAFF and APRIL. Here we report that γ-secretase directly cleaves BCMA, without prior truncation by another protease. This direct shedding is facilitated by the short length of BCMA's extracellular domain. In vitro, γ-secretase reduces BCMA-mediated NF-κB activation. In addition, γ-secretase releases soluble BCMA (sBCMA) that acts as a decoy neutralizing APRIL. In vivo, inhibition of γ-secretase enhances BCMA surface expression in plasma cells and increases their number in the bone marrow. Furthermore, in multiple sclerosis, sBCMA levels in spinal fluid are elevated and associated with intracerebral IgG production; in systemic lupus erythematosus, sBCMA levels in serum are elevated and correlate with disease activity. Together, shedding of BCMA by γ-secretase controls plasma cells in the bone marrow and yields a potential biomarker for B-cell involvement in human autoimmune diseases.


Assuntos
Secretases da Proteína Precursora do Amiloide/metabolismo , Antígeno de Maturação de Linfócitos B/metabolismo , Plasmócitos/metabolismo , Secretases da Proteína Precursora do Amiloide/antagonistas & inibidores , Diferenciação Celular , Células HEK293 , Humanos , Plasmócitos/citologia
15.
Ann Clin Transl Neurol ; 2(3): 295-301, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25815356

RESUMO

We present histological, MRI, and clinical features of an adult patient with relapsing encephalomyelitis and antibodies against myelin oligodendrocyte glycoprotein (MOG). Furthermore, we report molecular details of the recognized epitope that is specific for human MOG. A brain biopsy revealed multiple sclerosis (MS)-type II pathology. Some features overlapped with both MS and neuromyelitis optica spectrum disorders (NMOSD), whereas others were distinct from both MS and NMOSD. Immunoadsorption and rituximab induced clinical stabilization. This case contributes a new, so far missing link in the emerging spectrum of MOG-antibody-associated encephalomyelitis.

16.
J Immunol ; 194(2): 542-52, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25505277

RESUMO

BAFF and a proliferation-inducing ligand (APRIL), which control B cell homeostasis, are therapeutic targets in autoimmune diseases. TACI-Fc (atacicept), a soluble fusion protein containing the extracellular domain of the BAFF-APRIL receptor TACI, was applied in clinical trials. However, disease activity in multiple sclerosis unexpectedly increased, whereas in systemic lupus erythematosus, atacicept was beneficial. In this study, we show that an endogenous soluble TACI (sTACI) exists in vivo. TACI proteolysis involved shedding by a disintegrin and metalloproteinase 10 releasing sTACI from activated B cells. The membrane-bound stub was subsequently cleaved by γ-secretase reducing ligand-independent signaling of the remaining C-terminal fragment. The shed ectodomain assembled ligand independently in a homotypic way. It functioned as a decoy receptor inhibiting BAFF- and APRIL-mediated B cell survival and NF-κB activation. We determined sTACI levels in autoimmune diseases with established hyperactivation of the BAFF-APRIL system. sTACI levels were elevated both in the cerebrospinal fluid of the brain-restricted autoimmune disease multiple sclerosis correlating with intrathecal IgG production, as well as in the serum of the systemic autoimmune disease systemic lupus erythematosus correlating with disease activity. Together, we show that TACI is sequentially processed by a disintegrin and metalloproteinase 10 and γ-secretase. The released sTACI is an immunoregulator that shares decoy functions with atacicept. It reflects systemic and compartmentalized B cell accumulation and activation.


Assuntos
Proteínas ADAM/imunologia , Secretases da Proteína Precursora do Amiloide/imunologia , Linfócitos B/imunologia , Ativação Linfocitária , Proteínas de Membrana/imunologia , Esclerose Múltipla/imunologia , Proteína Transmembrana Ativadora e Interagente do CAML/imunologia , Proteínas ADAM/genética , Proteína ADAM10 , Secretases da Proteína Precursora do Amiloide/genética , Animais , Autoanticorpos/imunologia , Fator Ativador de Células B/genética , Fator Ativador de Células B/imunologia , Linfócitos B/patologia , Linhagem Celular , Membrana Celular/genética , Membrana Celular/imunologia , Feminino , Humanos , Imunoglobulina G/imunologia , Masculino , Proteínas de Membrana/genética , Camundongos , Esclerose Múltipla/patologia , Proteína Transmembrana Ativadora e Interagente do CAML/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/genética , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia
17.
PLoS One ; 7(1): e28094, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22276094

RESUMO

BACKGROUND: B cells and humoral immune responses play an important role in the pathogenesis and diagnosis of multiple sclerosis (MS). A characteristic finding in patients with MS is a polyspecific intrathecal B cell response against neurotropic viruses, specifically against measles virus, rubella virus, and varicella zoster virus, also known as an MRZ reaction (MRZR). Here, we correlated from the routine clinical diagnostics individual IgG antibody indices (AIs) of MRZR with magnetic resonance imaging (MRI) findings in patients with first MS diagnosis. METHODS/RESULTS: MRZR was determined in 68 patients with a clinically isolated syndrome (CIS) or early relapsing-remitting MS (RRMS). Absolute AI values for measles virus, rubella virus, and varicella zoster virus were correlated with T2 lesion load and gadolinium enhancing lesions on cerebral MRI (cMRI) and cMRI combined with spinal MRI (sMRI). Measles virus AI correlated significantly with T2 lesion load on cMRI (p = 0.0312, Mann-Whitney U test) and the sum of lesions on cMRI and sMRI (p = 0.0413). Varicella zoster virus AI also showed a correlation with T2 lesion load on cMRI but did not reach statistical significance (p = 0.2893). CONCLUSION: The results confirm MRZR as part of the polyspecific immune reaction in MS with possible prognostic impact on MRI and clinical parameters. Furthermore, the data indicate that intrathecal measles virus IgG production correlates with disease activity on cMRI and sMRI in patients with early MS.


Assuntos
Anticorpos Antivirais/imunologia , Imunoglobulina G/imunologia , Imageamento por Ressonância Magnética/métodos , Vírus do Sarampo/imunologia , Sarampo/imunologia , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/virologia , Adulto Jovem
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