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1.
Elife ; 122024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38775664

RESUMO

Cardiac macrophages are heterogenous in phenotype and functions, which has been associated with differences in their ontogeny. Despite extensive research, our understanding of the precise role of different subsets of macrophages in ischemia/reperfusion (I/R) injury remains incomplete. We here investigated macrophage lineages and ablated tissue macrophages in homeostasis and after I/R injury in a CSF1R-dependent manner. Genomic deletion of a fms-intronic regulatory element (FIRE) in the Csf1r locus resulted in specific absence of resident homeostatic and antigen-presenting macrophages, without affecting the recruitment of monocyte-derived macrophages to the infarcted heart. Specific absence of homeostatic, monocyte-independent macrophages altered the immune cell crosstalk in response to injury and induced proinflammatory neutrophil polarization, resulting in impaired cardiac remodeling without influencing infarct size. In contrast, continuous CSF1R inhibition led to depletion of both resident and recruited macrophage populations. This augmented adverse remodeling after I/R and led to an increased infarct size and deterioration of cardiac function. In summary, resident macrophages orchestrate inflammatory responses improving cardiac remodeling, while recruited macrophages determine infarct size after I/R injury. These findings attribute distinct beneficial effects to different macrophage populations in the context of myocardial infarction.


Assuntos
Macrófagos , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos , Animais , Macrófagos/imunologia , Camundongos , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/genética , Isquemia Miocárdica/imunologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/imunologia , Masculino , Traumatismo por Reperfusão Miocárdica/imunologia , Traumatismo por Reperfusão Miocárdica/patologia , Camundongos Endogâmicos C57BL , Miocárdio/patologia , Miocárdio/imunologia , Modelos Animais de Doenças
2.
Cells ; 13(6)2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38534352

RESUMO

Myasthenia gravis (MG) is a prototypical autoimmune disease of the neuromuscular junction (NMJ). The study of the underlying pathophysiology has provided novel insights into the interplay of autoantibodies and complement-mediated tissue damage. Experimental autoimmune myasthenia gravis (EAMG) emerged as a valuable animal model, designed to gain further insight and to test novel therapeutic approaches for MG. However, the availability of native acetylcholine receptor (AChR) protein is limited favouring the use of recombinant proteins. To provide a simplified platform for the study of MG, we established a model of EAMG using a recombinant protein containing the immunogenic sequence of AChR in mice. This model recapitulates key features of EAMG, including fatigable muscle weakness, the presence of anti-AChR-antibodies, and engagement of the NMJ by complement and a reduced NMJ density. Further characterization of this model demonstrated a prominent B cell immunopathology supported by T follicular helper cells. Taken together, the herein-presented EAMG model may be a valuable tool for the study of MG pathophysiology and the pre-clinical testing of therapeutic applications.


Assuntos
Miastenia Gravis Autoimune Experimental , Receptores Colinérgicos , Camundongos , Animais , Miastenia Gravis Autoimune Experimental/tratamento farmacológico , Miastenia Gravis Autoimune Experimental/metabolismo , Junção Neuromuscular/patologia , Proteínas do Sistema Complemento , Autoanticorpos , Imunização
4.
Int J Mol Sci ; 25(2)2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38255863

RESUMO

Multiple sclerosis (MS) is an autoimmune disease of the central nervous system (CNS) of still unclear etiology. In recent years, the search for biomarkers facilitating its diagnosis, prognosis, therapy response, and other parameters has gained increasing attention. In this regard, in a previous meta-analysis comprising 22 studies, we found that MS is associated with higher nitrite/nitrate (NOx) levels in the cerebrospinal fluid (CSF) compared to patients with non-inflammatory other neurological diseases (NIOND). However, many of the included studies did not distinguish between the different clinical subtypes of MS, included pre-treated patients, and inclusion criteria varied. As a follow-up to our meta-analysis, we therefore aimed to analyze the serum and CSF NOx levels in clinically well-defined cohorts of treatment-naïve MS patients compared to patients with somatic symptom disorder. To this end, we analyzed the serum and CSF levels of NOx in 117 patients (71 relapsing-remitting (RR) MS, 16 primary progressive (PP) MS, and 30 somatic symptom disorder). We found that RRMS and PPMS patients had higher serum NOx levels compared to somatic symptom disorder patients. This difference remained significant in the subgroup of MRZ-negative RRMS patients. In conclusion, the measurement of NOx in the serum might indeed be a valuable tool in supporting MS diagnosis.


Assuntos
Doenças Autoimunes , Sintomas Inexplicáveis , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Esclerose Múltipla/diagnóstico , Estresse Nitrosativo , Sistema Nervoso Central
5.
Acta Neuropathol ; 146(5): 725-745, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37773216

RESUMO

Inclusion body myositis (IBM) is unique across the spectrum of idiopathic inflammatory myopathies (IIM) due to its distinct clinical presentation and refractoriness to current treatment approaches. One explanation for this resistance may be the engagement of cell-autonomous mechanisms that sustain or promote disease progression of IBM independent of inflammatory activity. In this study, we focused on senescence of tissue-resident cells as potential driver of disease. For this purpose, we compared IBM patients to non-diseased controls and immune-mediated necrotizing myopathy patients. Histopathological analysis suggested that cellular senescence is a prominent feature of IBM, primarily affecting non-myogenic cells. In-depth analysis by single nuclei RNA sequencing allowed for the deconvolution and study of muscle-resident cell populations. Among these, we identified a specific cluster of fibro-adipogenic progenitors (FAPs) that demonstrated key hallmarks of senescence, including a pro-inflammatory secretome, expression of p21, increased ß-galactosidase activity, and engagement of senescence pathways. FAP function is required for muscle cell health with changes to their phenotype potentially proving detrimental. In this respect, the transcriptomic landscape of IBM was also characterized by changes to the myogenic compartment demonstrating a pronounced loss of type 2A myofibers and a rarefication of acetylcholine receptor expressing myofibers. IBM muscle cells also engaged a specific pro-inflammatory phenotype defined by intracellular complement activity and the expression of immunogenic surface molecules. Skeletal muscle cell dysfunction may be linked to FAP senescence by a change in the collagen composition of the latter. Senescent FAPs lose collagen type XV expression, which is required to support myofibers' structural integrity and neuromuscular junction formation in vitro. Taken together, this study demonstrates an altered phenotypical landscape of muscle-resident cells and that FAPs, and not myofibers, are the primary senescent cell type in IBM.


Assuntos
Miosite de Corpos de Inclusão , Miosite , Humanos , Miosite de Corpos de Inclusão/metabolismo , Adipogenia , Colágeno/metabolismo , Músculo Esquelético/metabolismo
6.
Front Immunol ; 14: 1198860, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37600819

RESUMO

Introduction: Given its wide availability and cost-effectiveness, multidimensional flow cytometry (mFC) became a core method in the field of immunology allowing for the analysis of a broad range of individual cells providing insights into cell subset composition, cellular behavior, and cell-to-cell interactions. Formerly, the analysis of mFC data solely relied on manual gating strategies. With the advent of novel computational approaches, (semi-)automated gating strategies and analysis tools complemented manual approaches. Methods: Using Bayesian network analysis, we developed a mathematical model for the dependencies of different obtained mFC markers. The algorithm creates a Bayesian network that is a HC tree when including raw, ungated mFC data of a randomly selected healthy control cohort (HC). The HC tree is used to classify whether the observed marker distribution (either patients with amyotrophic lateral sclerosis (ALS) or HC) is predicted. The relative number of cells where the probability q is equal to zero is calculated reflecting the similarity in the marker distribution between a randomly chosen mFC file (ALS or HC) and the HC tree. Results: Including peripheral blood mFC data from 68 ALS and 35 HC, the algorithm could correctly identify 64/68 ALS cases. Tuning of parameters revealed that the combination of 7 markers, 200 bins, and 20 patients achieved the highest AUC on a significance level of p < 0.0001. The markers CD4 and CD38 showed the highest zero probability. We successfully validated our approach by including a second, independent ALS and HC cohort (55 ALS and 30 HC). In this case, all ALS were correctly identified and side scatter and CD20 yielded the highest zero probability. Finally, both datasets were analyzed by the commercially available algorithm 'Citrus', which indicated superior ability of Bayesian network analysis when including raw, ungated mFC data. Discussion: Bayesian network analysis might present a novel approach for classifying mFC data, which does not rely on reduction techniques, thus, allowing to retain information on the entire dataset. Future studies will have to assess the performance when discriminating clinically relevant differential diagnoses to evaluate the complementary diagnostic benefit of Bayesian network analysis to the clinical routine workup.


Assuntos
Esclerose Lateral Amiotrófica , Citometria de Fluxo , Citometria de Fluxo/classificação , Citometria de Fluxo/métodos , Teorema de Bayes , Algoritmos , Esclerose Lateral Amiotrófica/diagnóstico , Humanos , Modelos Teóricos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais
7.
Sci Adv ; 9(23): eabq7595, 2023 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-37294768

RESUMO

Autoimmune limbic encephalitis (ALE) presents with new-onset mesial temporal lobe seizures, progressive memory disturbance, and other behavioral and cognitive changes. CD8 T cells are considered to play a key role in those cases where autoantibodies (ABs) target intracellular antigens or no ABs were found. Assessment of such patients presents a clinical challenge, and novel noninvasive imaging biomarkers are urgently needed. Here, we demonstrate that visualization of the translocator protein (TSPO) with [18F]DPA-714-PET-MRI reveals pronounced microglia activation and reactive gliosis in the hippocampus and amygdala of patients suspected with CD8 T cell ALE, which correlates with FLAIR-MRI and EEG alterations. Back-translation into a preclinical mouse model of neuronal antigen-specific CD8 T cell-mediated ALE allowed us to corroborate our preliminary clinical findings. These translational data underline the potential of [18F]DPA-714-PET-MRI as a clinical molecular imaging method for the direct assessment of innate immunity in CD8 T cell-mediated ALE.


Assuntos
Encefalite Límbica , Animais , Humanos , Camundongos , Proteínas de Transporte/metabolismo , Inflamação/metabolismo , Encefalite Límbica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Receptores de GABA/metabolismo
8.
JCI Insight ; 8(13)2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37227781

RESUMO

Therapeutic strategies targeting complement have revolutionized the treatment of myasthenia gravis (MG). However, a deeper understanding of complement modulation in the human system is required to improve treatment responses and identify off-target effects shaping long-term outcomes. For this reason, we studied a cohort of patients with MG treated with either eculizumab or azathioprine as well as treatment-naive patients using a combined proteomics and metabolomics approach. This strategy validated known effects of eculizumab on the terminal complement cascade. Beyond that, eculizumab modulated the serum proteometabolome as distinct pathways were altered in eculizumab-treated patients, including the oxidative stress response, mitogen-activated protein kinase signaling, and lipid metabolism with particular emphasis on arachidonic acid signaling. We detected reduced levels of arachidonate 5-lipoxygenase (ALOX5) and leukotriene A4 in eculizumab-treated patients. Mechanistically, ligation of the C5a receptor (C5aR) is needed for ALOX5 metabolism and generation of downstream leukotrienes. As eculizumab prevents cleavage of C5 into C5a, decreased engagement of C5aR may inhibit ALOX5-mediated synthesis of pro-inflammatory leukotrienes. These findings indicate distinct off-target effects induced by eculizumab, illuminating potential mechanisms of action that may be harnessed to improve treatment outcomes.


Assuntos
Complemento C5 , Miastenia Gravis , Humanos , Proteínas do Sistema Complemento , Ativação do Complemento , Miastenia Gravis/tratamento farmacológico , Receptor da Anafilatoxina C5a , Leucotrienos
9.
Artigo em Inglês | MEDLINE | ID: mdl-37041077

RESUMO

BACKGROUND AND OBJECTIVES: B cell-depleting antibodies were proven as effective strategy for the treatment of relapsing multiple sclerosis (RMS). The monoclonal antibody ocrelizumab was approved in 2017 in the United States and in 2018 in the European Union, but despite proven efficacy in randomized, controlled clinical trials, its effectiveness in the real-world setting remains to be fully elucidated. In particular, most study patients were treatment naive or switched from injectable therapies, whereas oral substances or monoclonal antibodies made up >1% of previous treatments. METHODS: We evaluated ocrelizumab-treated patients with RMS enrolled in the prospective cohorts at the University Hospitals Duesseldorf and Essen, Germany. Epidemiologic data at baseline were compared, and Cox proportional hazard models were applied to evaluate outcomes. RESULTS: Two hundred eighty patients were included (median age: 37 years, 35% male patients). Compared with using ocrelizumab as a first-line treatment, its use as a third-line therapy increased hazard ratios (HRs) for relapse and disability progression, whereas differences between first- vs second-line and second- vs third-line remained smaller. We stratified patients according to their last previous disease-modifying treatment and here identified fingolimod (FTY) (45 patients, median age 40 years, 33% male patients) as a relevant risk factor for ongoing relapse activity despite 2nd-line (HR: 3.417 [1.007-11.600]) or 3rd-line (HR: 5.903 [2.489-13.999]) ocrelizumab treatment, disability worsening (2nd line: HR: 3.571 [1.013-12.589]; 3rd line: HR: 4.502 [1.728-11.729]), and occurrence of new/enlarging MRI lesions (2nd line: HR: 1.939 [0.604-6.228]; 3rd line: HR: 4.627 [1.982-10.802]). Effects were persistent throughout the whole follow-up. Neither peripheral B-cell repopulation nor immunoglobulin G levels were associated with rekindling disease activity. DISCUSSION: Our prospectively collected observational data suggest suboptimal effectiveness of ocrelizumab in patients switching from FTY compared with those switching from other substances or having been treatment naive. These findings support previous studies indicating abated effectiveness of immune cell-depleting therapies following FTY treatment in patients with RMS. CLASSIFICATION OF EVIDENCE: This study provides Class IV evidence that for patients with RMS, previous treatment with FTY compared with previous treatment with other immunomodulating therapies decreases the effectiveness of ocrelizumab.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Masculino , Estados Unidos , Adulto , Feminino , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Estudos Prospectivos , Esclerose Múltipla/tratamento farmacológico , Resultado do Tratamento , Soro Antilinfocitário , Recidiva
10.
Digit Health ; 9: 20552076231152989, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36762020

RESUMO

Objective: Due to the growing complexity in monitoring and treatment of many disorders, disease-specific care and research networks offer patients certified healthcare. However, the networks' ability to provide health services close to patients' homes usually remains vague. Digital Health Technologies (DHTs) help to provide better care, especially if implemented in a targeted manner in regions undersupplied by specialised networks. Therefore, we used a car travel time-based isochrone approach to identify care gaps using the example of the neuroinflammation-focused German healthcare and research networks for multiple sclerosis (MS), myasthenia gravis (MG), myositis and immune-mediated neuropathy. Methods: Excellence centres were mapped, and isochrones for 30, 60, 90 and 120 minutes were calculated. The resulting geometric figures were aggregated and used to mask the global human settlement population grid 2019 to estimate German inhabitants that can reach centres within the given periods. Results: While 96.48% of Germans can drive to an MS-focused centre within one hour, coverage is lower for the rare disease networks for MG (48.3%), myositis (43.1%) and immune-mediated neuropathy (56.7%). Within 120 minutes, more than 80% of Germans can reach a centre of any network. Besides the generally worse covered rural regions such as North-Eastern Germany, the rare disease networks also show network-specific regional underrepresentation. Conclusion: An isochrone-based approach helps identify regions where specialised care is hard to reach, which might be especially troublesome in the case of an often disabled patient collective. Patient care could be improved by focusing deployments of disease-specific DHTs on these areas.

11.
J Autoimmun ; 135: 102985, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36621173

RESUMO

Autoimmune Encephalitis (AE) spans a group of non-infectious inflammatory conditions of the central nervous system due to an imbalanced immune response. Aiming to elucidate the pathophysiological mechanisms of AE, we applied an unsupervised proteomic approach to analyze the cerebrospinal fluid (CSF) protein profile of AE patients with autoantibodies against N-methyl-d-aspartate receptor (NMDAR) (n = 9), leucine-rich glioma-inactivated protein 1 (LGI1) (n = 9), or glutamate decarboxylase 65 (GAD65) (n = 8) compared to 9 patients with relapsing-remitting multiple sclerosis as inflammatory controls, and 10 patients with somatic symptom disorder as non-inflammatory controls. We found a dysregulation of the complement system, a disbalance between pro-inflammatory and anti-inflammatory proteins on the one hand, and dysregulation of proteins involved in synaptic transmission, synaptogenesis, brain connectivity, and neurodegeneration on the other hand to a different extent in all AE subtypes compared to non-inflammatory controls. Furthermore, elevated levels of several proteases and reduction in protease inhibitors could be detected in all AE subtypes compared to non-inflammatory controls. Moreover, the different AE subtypes showed distinct protein profiles compared to each other and inflammatory controls which may facilitate future identification of disease-specific biomarkers. Overall, CSF proteomics provides insights into the complex pathophysiological mechanisms of AE, including immune dysregulation, neuronal dysfunction, neurodegeneration, and altered protease function.


Assuntos
Encefalite , Esclerose Múltipla Recidivante-Remitente , Humanos , Proteômica , Proteínas , Autoanticorpos
12.
Brain ; 146(3): 977-990, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35348614

RESUMO

Autoimmune neurological syndromes (AINS) with autoantibodies against the 65 kDa isoform of the glutamic acid decarboxylase (GAD65) present with limbic encephalitis, including temporal lobe seizures or epilepsy, cerebellitis with ataxia, and stiff-person-syndrome or overlap forms. Anti-GAD65 autoantibodies are also detected in autoimmune diabetes mellitus, which has a strong genetic susceptibility conferred by human leukocyte antigen (HLA) and non-HLA genomic regions. We investigated the genetic predisposition in patients with anti-GAD65 AINS. We performed a genome-wide association study (GWAS) and an association analysis of the HLA region in a large German cohort of 1214 individuals. These included 167 patients with anti-GAD65 AINS, recruited by the German Network for Research on Autoimmune Encephalitis (GENERATE), and 1047 individuals without neurological or endocrine disease as population-based controls. Predictions of protein expression changes based on GWAS findings were further explored and validated in the CSF proteome of a virtually independent cohort of 10 patients with GAD65-AINS and 10 controls. Our GWAS identified 16 genome-wide significant (P < 5 × 10-8) loci for the susceptibility to anti-GAD65 AINS. The top variant, rs2535288 [P = 4.42 × 10-16, odds ratio (OR) = 0.26, 95% confidence interval (CI) = 0.187-0.358], localized to an intergenic segment in the middle of the HLA class I region. The great majority of variants in these loci (>90%) mapped to non-coding regions of the genome. Over 40% of the variants have known regulatory functions on the expression of 48 genes in disease relevant cells and tissues, mainly CD4+ T cells and the cerebral cortex. The annotation of epigenomic marks suggested specificity for neural and immune cells. A network analysis of the implicated protein-coding genes highlighted the role of protein kinase C beta (PRKCB) and identified an enrichment of numerous biological pathways participating in immunity and neural function. Analysis of the classical HLA alleles and haplotypes showed no genome-wide significant associations. The strongest associations were found for the DQA1*03:01-DQB1*03:02-DRB1*04:01HLA haplotype (P = 4.39 × 10-4, OR = 2.5, 95%CI = 1.499-4.157) and DRB1*04:01 allele (P = 8.3 × 10-5, OR = 2.4, 95%CI = 1.548-3.682) identified in our cohort. As predicted, the CSF proteome showed differential levels of five proteins (HLA-A/B, C4A, ATG4D and NEO1) of expression quantitative trait loci genes from our GWAS in the CSF proteome of anti-GAD65 AINS. These findings suggest a strong genetic predisposition with direct functional implications for immunity and neural function in anti-GAD65 AINS, mainly conferred by genomic regions outside the classical HLA alleles.


Assuntos
Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Predisposição Genética para Doença/genética , Proteoma/genética , Antígenos de Histocompatibilidade Classe II , Antígenos HLA , Haplótipos , Alelos , Autoanticorpos , Cadeias HLA-DRB1/genética
13.
Artigo em Inglês | MEDLINE | ID: mdl-36521587

RESUMO

Social interaction difficulties are a hallmark of psychotic disorders, which in some cases can be definitely traced back to autoimmunological causes. Interestingly, systemic and intrathecal inflammation have been shown to significantly influence social processing by increasing sensitivity to threatening social stimuli, which bears some resemblance to psychosis. In this article, we review evidence for the involvement of systemic and intrathecal inflammatory processes in psychotic disorders and how this might help to explain some of the social impairments associated with this group of disorders. Vice versa, we also discuss evidence for the immunomodulatory function of social interactions and their potential role for therapeutic interventions in psychotic disorders.


Assuntos
Transtornos Psicóticos , Interação Social , Humanos , Inflamação
14.
J Neuroinflammation ; 19(1): 270, 2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36348455

RESUMO

BACKGROUND: Cladribine is a synthetic purine analogue that interferes with DNA synthesis and repair next to disrupting cellular proliferation in actively dividing lymphocytes. The compound is approved for the treatment of multiple sclerosis (MS). Cladribine can cross the blood-brain barrier, suggesting a potential effect on central nervous system (CNS) resident cells. Here, we explored compartment-specific immunosuppressive as well as potential direct neuroprotective effects of oral cladribine treatment in experimental autoimmune encephalomyelitis (EAE) mice. METHODS: In the current study, we compare immune cell frequencies and phenotypes in the periphery and CNS of EAE mice with distinct grey and white matter lesions (combined active and focal EAE) either orally treated with cladribine or vehicle, using flow cytometry. To evaluate potential direct neuroprotective effects, we assessed the integrity of the primary auditory cortex neuronal network by studying neuronal activity and spontaneous synaptic activity with electrophysiological techniques ex vivo. RESULTS: Oral cladribine treatment significantly attenuated clinical deficits in EAE mice. Ex vivo flow cytometry showed that cladribine administration led to peripheral immune cell depletion in a compartment-specific manner and reduced immune cell infiltration into the CNS. Histological evaluations revealed no significant differences for inflammatory lesion load following cladribine treatment compared to vehicle control. Single cell electrophysiology in acute brain slices was performed and showed an impact of cladribine treatment on intrinsic cellular firing patterns and spontaneous synaptic transmission in neurons of the primary auditory cortex. Here, cladribine administration in vivo partially restored cortical neuronal network function, reducing action potential firing. Both, the effect on immune cells and neuronal activity were transient. CONCLUSIONS: Our results indicate that cladribine exerts a neuroprotective effect after crossing the blood-brain barrier independently of its peripheral immunosuppressant action.


Assuntos
Encefalomielite Autoimune Experimental , Encefalomielite , Fármacos Neuroprotetores , Camundongos , Animais , Encefalomielite Autoimune Experimental/patologia , Cladribina/uso terapêutico , Fármacos Neuroprotetores/farmacologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Imunossupressores/uso terapêutico
15.
Cells ; 11(20)2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36291195

RESUMO

Chronic inflammation of skeletal muscle is the common feature of idiopathic inflammatory myopathies (IIM). Given the rarity of the disease and potential difficulty of routinely obtaining target tissue, i.e., standardized skeletal muscle, our understanding of immune signatures of the IIM spectrum remains incomplete. Further insight into the immune topography of IIM is needed to determine specific treatment targets according to clinical and immunological phenotypes. Thus, we used high-dimensional flow cytometry to investigate the immune phenotypes of anti-synthetase syndrome (ASyS), dermatomyositis (DM) and inclusion-body myositis (IBM) patients as representative entities of the IIM spectrum and compared them to healthy controls. We studied the CD8, CD4 and B cell compartments in the blood aiming to provide a contemporary overview of the immune topography of the IIM spectrum. ASyS was characterized by altered CD4 composition and expanded T follicular helper cells supporting B cell-mediated autoimmunity. For DM, unsupervised clustering identified expansion of distinct B cell subtypes highly expressing immunoglobulin G4 (IgG4) and CD38. Lastly, terminally differentiated, cytotoxic CD8 T cells distinguish IBM from other IIM. Interestingly, these terminally differentiated CD8 T cells highly expressed the integrin CD18 mediating cellular adhesion and infiltration. The distinct immune cell topography of IIM might provide the framework for targeted treatment approaches potentially improving therapeutic outcomes.


Assuntos
Miosite de Corpos de Inclusão , Miosite , Humanos , Miosite/metabolismo , Músculo Esquelético/metabolismo , Integrinas/metabolismo , Imunoglobulina G/metabolismo
16.
Cell Mol Life Sci ; 79(9): 479, 2022 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-35951110

RESUMO

Blood-brain barrier (BBB) integrity is necessary to maintain homeostasis of the central nervous system (CNS). NMDA receptor (NMDAR) function and expression have been implicated in BBB integrity. However, as evidenced in neuroinflammatory conditions, BBB disruption contributes to immune cell infiltration and propagation of inflammatory pathways. Currently, our understanding of the pathophysiological role of NMDAR signaling on endothelial cells remains incomplete. Thus, we investigated NMDAR function on primary mouse brain microvascular endothelial cells (MBMECs). We detected glycine-responsive NMDAR channels, composed of functional GluN1, GluN2A and GluN3A subunits. Importantly, application of glycine alone, but not glutamate, was sufficient to induce NMDAR-mediated currents and an increase in intracellular Ca2+ concentrations. Functionally, glycine-mediated NMDAR activation leads to loss of BBB integrity and changes in actin distribution. Treatment of oocytes that express NMDARs composed of different subunits, with GluN1 and GluN3A binding site inhibitors, resulted in abrogation of NMDAR signaling as measured by two-electrode voltage clamp (TEVC). This effect was only detected in the presence of the GluN2A subunits, suggesting the latter as prerequisite for pharmacological modulation of NMDARs on brain endothelial cells. Taken together, our findings argue for a novel role of glycine as NMDAR ligand on endothelial cells shaping BBB integrity.


Assuntos
Glicina , Receptores de N-Metil-D-Aspartato , Animais , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Glicina/metabolismo , Glicina/farmacologia , Camundongos , N-Metilaspartato/farmacologia , Receptores de Glicina , Receptores de N-Metil-D-Aspartato/metabolismo
17.
Vaccines (Basel) ; 10(7)2022 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-35891296

RESUMO

Neuromyotonia is a rare peripheral nerve hyperexcitability syndrome often associated with antibodies directed against contactin-associated protein-like 2 and leucine-rich, glioma inactivated 1. The quadrivalent human papilloma virus vaccine Gardasil®, first approved in 2006, is known to be a highly effective prophylaxis against papillomavirus types 6, 11, 16, and 18. Molecularly, this non-infectious recombinant vaccine is based on purified L1 proteins from the human papilloma virus capsid. Since the approval of this vaccine, several studies have investigated its safety regarding the occurrence of autoimmune conditions following application. Here, we present the first case of neuromyotonia with active Gadolinium enhancing demyelinating central nervous system lesions following vaccination with Gardasil®.

18.
Mult Scler Relat Disord ; 63: 103927, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35700670

RESUMO

BACKGROUND: The current range of disease-modifying treatments (DMTs) for relapsing-remitting multiple sclerosis (RRMS) has placed more importance on the accurate monitoring of disease progression for timely and appropriate treatment decisions. With a rising number of measurements for disease progression, it is currently unclear how well these measurements or combinations of them can monitor more mildly affected RRMS patients. OBJECTIVES: To investigate several composite measures for monitoring disease activity and their potential relation to the biomarker neurofilament light chain (NfL) in a clearly defined early RRMS patient cohort with a milder disease course. METHODS: From a total of 301 RRMS patients, a subset of 46 patients being treated with a continuous first-line therapy was analyzed for loss of no evidence of disease activity (lo-NEDA-3) status, relapse-associated worsening (RAW) and progression independent of relapse activity (PIRA), up to seven years after treatment initialization. Kaplan-Meier estimates were used for time-to-event analysis. Additionally, a Cox regression model was used to analyze the effect of NfL levels on outcome measures in this cohort. RESULTS: In this mildly affected cohort, both lo-NEDA-3 and PIRA frequently occurred over a median observational period of 67.2 months and were observed in 39 (84.8%) and 23 (50.0%) patients, respectively. Additionally, 12 out of 26 PIRA manifestations (46.2%) were observed without a corresponding lo-NEDA-3 status. Jointly, either PIRA or lo-NEDA-3 showed disease activity in all patients followed-up for at least the median duration (67.2 months). NfL values demonstrated an association with the occurrence of relapses and RAW. CONCLUSION: The complementary use of different disease progression measures helps mirror ongoing disease activity in mildly affected early RRMS patients being treated with continuous first-line therapy.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Estudos de Coortes , Progressão da Doença , Humanos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Recidiva
19.
Biomedicines ; 10(6)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35740296

RESUMO

Retinoid X receptors (RXRs), as members of the steroid/thyroid hormone superfamily of nuclear receptors, are crucial regulators of immune response during health and disease. RXR subtype expression is dependent on tissue and cell type, RXRα being the relevant isoform in monocytes and macrophages. Previous studies have assessed different functions of RXRs and positive implications of RXR agonists on outcomes after ischemic injuries have been described. However, the impact of a reduced Rxrα expression in mononuclear phagocytes on cardiac remodeling after myocardial infarction (MI) has not been investigated to date. Here, we use a temporally controlled deletion of Rxrα in monocytes and macrophages to determine its role in ischemia-reperfusion injury. We show that reduced expression of Rxrα in mononuclear phagocytes leads to a decreased phagocytic activity and an accumulation of apoptotic cells in the myocardium, reduces angiogenesis and cardiac macrophage proliferation in the infarct border zone/infarct area, and has an impact on monocyte/macrophage subset composition. These changes are associated with a greater myocardial defect 30 days after ischemia/reperfusion injury. Overall, the reduction of Rxrα levels in monocytes and macrophages negatively impacts cardiac remodeling after myocardial infarction. Thus, RXRα might represent a therapeutic target to regulate the immune response after MI in order to improve cardiac remodeling.

20.
Arch Clin Neuropsychol ; 37(4): 738-752, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35136904

RESUMO

OBJECTIVE: Autoimmune limbic encephalitis (ALE) is characterized by memory impairment, psychiatric symptoms, and epileptic seizures. Though, the neuropsychological profile of ALE is not yet well defined. However, there is some evidence that neuropsychological impairments might exceed those related to the limbic system and that different autoantibodies (AABs) are associated with distinguishable pattern of neuropsychological impairments. We provide a comprehensive presentation of neuropsychological performance of ALE in an immune therapy-naïve sample. METHODS: We retrospectively analyzed 69 immunotherapy-naïve ALE-patients (26 seropositive-[8 LGI1-, 4 CASPR2-, 2 GABAB-R-, 3 Hu-, 4 GAD65-, 2 Ma2-, 2 unknown antigen, and 1 Yo-AABs] and 43 seronegative patients, mean age 56.0 years [21.9-78.2], mean disease duration 88 weeks [0-572]). Neuropsychological evaluations comprised of the domains memory, attention, praxis, executive functions, language, social cognition, and psychological symptoms. We compared these functions between seronegative -, seropositive patients with AABs against intracellular neural antigens and seropositive patients with AABs against surface membrane neural antigens. RESULTS: No effect of AAB group on neuropsychological performance could be detected. Overall, ALE predominantly presents with deficits in long-term memory and memory recognition, autobiographical-episodic memory loss, impairment of emotion recognition, and depressed mood. Furthermore, deficits in praxis of pantomimes and imitations, visuo-construction, and flexibility may occur. CONCLUSION: ALE shows a wide spectrum of neuropsychological impairments, which might exceed the limbic system, with no evidence of differences between AAB groups. Neuropsychological assessment for diagnosing ALE should include long-term memory, memory recognition, autobiographical-episodic memory, emotion recognition, and a detailed investigation of depression.


Assuntos
Autoanticorpos , Imageamento por Ressonância Magnética , Doenças Autoimunes , Humanos , Imunoterapia , Encefalite Límbica , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Retrospectivos
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