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Frontotemporal lobar degeneration with tau (FTLD-tau) is a group of tauopathies that underlie â¼50% of FTLD cases. Identification of genetic risk variants related to innate/adaptive immunity have highlighted a role for neuroinflammation and neuroimmune interactions in FTLD. Studies have shown microglial and astrocyte activation together with T cell infiltration in the brain of THY-Tau22 tauopathy mice. However, this remains to be confirmed in FTLD-tau patients. We conducted a detailed post-mortem study of FTLD-tau cases including 45 progressive supranuclear palsy with clinical frontotemporal dementia, 33 Pick's disease, 12 FTLD-MAPT and 52 control brains to characterize the link between phosphorylated tau (pTau) epitopes and the innate and adaptive immunity. Tau pathology was assessed in the cerebral cortex using antibodies directed against: Tau-2 (phosphorylated and unphosphorylated tau), AT8 (pSer202/pThr205), AT100 (pThr212/pSer214), CP13 (pSer202), PHF1 (pSer396/pSer404), pThr181 and pSer356. The immunophenotypes of microglia and astrocytes were assessed with phenotypic markers (Iba1, CD68, HLA-DR, CD64, CD32a, CD16 for microglia and GFAP, EAAT2, glutamine synthetase and ALDH1L1 for astrocytes). The adaptive immune response was explored via CD4+ and CD8+ T cell quantification and the neuroinflammatory environment was investigated via the expression of 30 inflammatory-related proteins using V-Plex Meso Scale Discovery. As expected, all pTau markers were increased in FTLD-tau cases compared to controls. pSer356 expression was greatest in FTLD-MAPT cases versus controls (P < 0.0001), whereas the expression of other markers was highest in Pick's disease. Progressive supranuclear palsy with frontotemporal dementia consistently had a lower pTau protein load compared to Pick's disease across tau epitopes. The only microglial marker increased in FTLD-tau was CD16 (P = 0.0292) and specifically in FTLD-MAPT cases (P = 0.0150). However, several associations were detected between pTau epitopes and microglia, supporting an interplay between them. GFAP expression was increased in FTLD-tau (P = 0.0345) with the highest expression in Pick's disease (P = 0.0019), while ALDH1L1 was unchanged. Markers of astrocyte glutamate cycling function were reduced in FTLD-tau (P = 0.0075; Pick's disease: P < 0.0400) implying astrocyte reactivity associated with a decreased glutamate cycling activity, which was further associated with pTau expression. Of the inflammatory proteins assessed in the brain, five chemokines were upregulated in Pick's disease cases (P < 0.0400), consistent with the recruitment of CD4+ (P = 0.0109) and CD8+ (P = 0.0014) T cells. Of note, the CD8+ T cell infiltration was associated with pTau epitopes and microglial and astrocytic markers. Our results highlight that FTLD-tau is associated with astrocyte reactivity, remarkably little activation of microglia, but involvement of adaptive immunity in the form of chemokine-driven recruitment of T lymphocytes.
Assuntos
Demência Frontotemporal , Degeneração Lobar Frontotemporal , Doença de Pick , Paralisia Supranuclear Progressiva , Tauopatias , Humanos , Epitopos , Demência Frontotemporal/patologia , Degeneração Lobar Frontotemporal/patologia , Glutamatos , Doença de Pick/patologia , Paralisia Supranuclear Progressiva/patologia , Proteínas tau/metabolismo , Tauopatias/patologiaRESUMO
AIMS: In Alzheimer's disease (AD), the locus coeruleus (LC) undergoes early and extensive neuronal loss, preceded by abnormal intracellular tau aggregation, decades before the onset of clinical disease. Neuromelanin-sensitive MRI has been proposed as a method to image these changes during life. Surprisingly, human post-mortem studies have not examined how changes in LC during the course of the disease relate to cerebral pathology following the loss of the LC projection to the cortex. METHODS: Immunohistochemistry was used to examine markers for 4G8 (pan-Aß) and AT8 (ptau), LC integrity (neuromelanin, dopamine ß-hydroxylase [DßH], tyrosine hydroxylase [TH]) and microglia (Iba1, CD68, HLA-DR) in the LC and related temporal lobe pathology of 59 post-mortem brains grouped by disease severity determined by Braak stage (0-II, III-IV and V-VI). The inflammatory environment was assessed using multiplex assays. RESULTS: Changes in the LC with increasing Braak stage included increased neuronal loss (p < 0.001) and microglial Iba1 (p = 0.005) together with a reduction in neuromelanin (p < 0.001), DßH (p = 0.002) and TH (p = 0.041). Interestingly in LC, increased ptau and loss of neuromelanin were detected from Braak stage III-IV (p = 0.001). At Braak stage V/VI, the inflammatory environment was different in the LC vs TL, highlighting the anatomical heterogeneity of the inflammatory response. CONCLUSIONS: Here, we report the first quantification of neuromelanin during the course of AD and its relationship to AD pathology and neuroinflammation in the TL. Our findings of neuromelanin loss early in AD and before the neuroinflammatory reaction support the use of neuromelanin-MRI as a sensitive technique to identify early changes in AD.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/patologia , Locus Cerúleo/metabolismo , Proteínas tau/metabolismo , Encéfalo/patologia , AutopsiaRESUMO
BACKGROUND: The airway microbiome in severe asthma has not been characterised at species-level by metagenomic sequencing, nor have the relationships between specific species and mucosal immune responses in 'type-2 low', neutrophilic asthma been defined. We performed an integrated species-level metagenomic data with inflammatory mediators to characterise prevalence of dominant potentially pathogenic organisms and host immune responses. METHODS: Sputum and nasal lavage samples were analysed using long-read metagenomic sequencing with Nanopore and qPCR in two cross-sectional adult severe asthma cohorts, Wessex (n = 66) and Oxford (n = 30). We integrated species-level data with clinical parameters and 39 selected airway proteins measured by immunoassay and O-link. RESULTS: The sputum microbiome in health and mild asthma displayed comparable microbial diversity. By contrast, 23% (19/81) of severe asthma microbiomes were dominated by a single respiratory pathogen, namely H. influenzae (n = 10), M. catarrhalis (n = 4), S. pneumoniae (n = 4) and P. aeruginosa (n = 1). Neutrophilic asthma was associated with H. influenzae, M. catarrhalis, S. pneumoniae and T. whipplei with elevated type-1 cytokines and proteases; eosinophilic asthma with higher M. catarrhalis, but lower H. influenzae, and S. pneumoniae abundance. H. influenzae load correlated with Eosinophil Cationic Protein, elastase and IL-10. R. mucilaginosa associated positively with IL-6 and negatively with FGF. Bayesian network analysis also revealed close and distinct relationships of H. influenzae and M. catarrhalis with type-1 airway inflammation. The microbiomes and cytokine milieu were distinct between upper and lower airways. CONCLUSIONS: This species-level integrated analysis reveals central, but distinct associations between potentially pathogenic bacteria and airways inflammation in severe asthma.
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The 18kD translocator protein (TSPO) is used as a positron emission tomography (PET) target to quantify neuroinflammation in patients. In Alzheimer's disease (AD), the cerebellum is the pseudo-reference region for comparison with the cerebral cortex due to the absence of AD pathology and lower levels of TSPO. However, using the cerebellum as a pseudo-reference region is debated, with other brain regions suggested as more suitable. This paper aimed to establish the neuroinflammatory differences between the temporal cortex and cerebellar cortex, including TSPO expression. Using 60 human post-mortem samples encompassing the spectrum of Braak stages (I-VI), immunostaining for pan-Aß, hyperphosphorylated (p)Tau, TSPO and microglial proteins Iba1, HLA-DR and MSR-A was performed in the temporal cortex and cerebellum. In the cerebellum, Aß but not pTau, increased over the course of the disease, in contrast to the temporal cortex, where both proteins were significantly increased. TSPO increased in the temporal cortex, more than twofold in the later stages of AD compared to the early stages, but not in the cerebellum. Conversely, Iba1 increased in the cerebellum, but not in the temporal cortex. TSPO was associated with pTau in the temporal cortex, suggesting that TSPO positive microglia may be reacting to pTau itself and/or neurodegeneration at later stages of AD. Furthermore, the neuroinflammatory microenvironment was examined, using MesoScale Discovery assays, and IL15 only was significantly increased in the temporal cortex. Together this data suggests that the cerebellum maintains a more homeostatic environment compared to the temporal cortex, with a consistent TSPO expression, supporting its use as a pseudo-reference region for quantification in TSPO PET scans.
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Doença de Alzheimer , Humanos , Doença de Alzheimer/patologia , Doenças Neuroinflamatórias , Proteínas Mitocondriais/metabolismo , Encéfalo/metabolismo , Microglia/metabolismo , Tomografia por Emissão de Pósitrons/métodos , Receptores de GABA/metabolismoRESUMO
BACKGROUND: IL-13 is considered an archetypal T2 cytokine central to the clinical disease expression of asthma. The IL-13 response genes, which are upregulated in central airway bronchial epithelial of asthma patients, can be normalized by high-dose inhaled steroid therapy in severe asthma. However, this is not the case within the peripheral airways. We have sought to further understand IL-13 in the peripheral airways in severe asthma through bronchoalveolar analysis. METHODS: Bronchoalveolar lavage samples were collected from 203 asthmatic and healthy volunteers, including 78 with severe asthma. Inflammatory mediators were measured using a multiple cytokine immunoassay platform. This analysis was replicated in a further 59 volunteers, in whom 16S rRNA analysis of BAL samples was undertaken by terminal restriction fragment length polymorphism. RESULTS: Severe asthma patients with high BAL IL-13, despite treatment with high-dose inhaled corticosteroids, had more severe lung function and significantly higher BAL neutrophil percentages, but not BAL eosinophils than those with normal BAL-13 concentrations. This finding was replicated in the second cohort, which further associated BAL IL-13 and neutrophilia with a greater abundance of potentially pathogenic bacteria in the peripheral airways. CONCLUSION: Our findings demonstrate a steroid unresponsive source of IL-13 that is associated with BAL neutrophilia and bacterial dysbiosis in severe asthma. Our findings highlight the biological complexity of severe asthma and the importance of a greater understanding of the innate and adaptive immune responses in the peripheral airways in this disease.
Assuntos
Asma , Disbiose , Asma/tratamento farmacológico , Brônquios , Líquido da Lavagem Broncoalveolar , Eosinófilos , Humanos , Inflamação , RNA Ribossômico 16S/genéticaRESUMO
BACKGROUND: Hair cortisol concentration (HCC) can be used to periodically assess hypothalamic-pituitary-adrenal (HPA) axis function, and appears correlated with prolonged exposure to stress. METHODS: Serial assessment (at Baseline, Week 6 and Week 12) of participants (n = 35) with anxiety disorders by psychopathological rating scales, with assays of HCC and levels of peripheral anti- and pro-inflammatory cytokines. Patients underwent antidepressant treatment for an initial 6 weeks, followed by cyclo-oxygenase inhibitor-2 (COX-2) inhibitor (celecoxib) augmentation or 'treatment as usual' for a further 6 weeks. RESULTS: At Baseline (n = 35), HCC was elevated in patients with single-episode but not recurrent-episode anxiety disorders, mean IL-12p70 levels were low, and mean TNF-α levels were elevated. Following 6 weeks of antidepressant treatment (n = 33), mean HCC was within the normal range but mean IL-2 level was low. Celecoxib augmentation (n = 18) was associated with a reduction in anxiety symptoms and normalisation of mean IL-2 levels. LIMITATIONS: Small sample size. Not all participants were assessed at all time points. CONCLUSION: Serial assessment of HCC is practicable in patients with anxiety disorders. These preliminary findings warrant further investigation in larger samples.
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Transtornos de Ansiedade/metabolismo , Transtornos de Ansiedade/psicologia , Cabelo/metabolismo , Hidrocortisona/análise , Inflamação/metabolismo , Adulto , Antidepressivos/efeitos adversos , Antidepressivos/uso terapêutico , Transtornos de Ansiedade/tratamento farmacológico , Biomarcadores/metabolismo , Estudos de Casos e Controles , Inibidores de Ciclo-Oxigenase 2/efeitos adversos , Inibidores de Ciclo-Oxigenase 2/uso terapêutico , Citocinas/sangue , Quimioterapia Combinada , Feminino , Humanos , Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Sistema Hipotálamo-Hipofisário/fisiologia , Interleucina-12/análise , Interleucina-2/análise , Masculino , Pessoa de Meia-Idade , Sistema Hipófise-Suprarrenal/efeitos dos fármacos , Sistema Hipófise-Suprarrenal/fisiologia , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/análise , Fator de Necrose Tumoral alfa/efeitos dos fármacosRESUMO
BACKGROUND: Inflammation plays a key role in the aetiology and progression of Alzheimer's disease (AD). However, the immunophenotype of the second most common neurodegenerative cause of dementia, dementia with Lewy bodies (DLB), remains unclear. To date there have been no studies examining peripheral inflammation in DLB using multiplex immunoassay and flow cytometry concomitantly. We hypothesised that, using blood biomarkers, DLB would show an increased proinflammatory profile compared with controls, and that there would be a distinct profile compared with AD. METHODS: 93 participants (31 with DLB, 31 with AD and 31 healthy older controls) completed a single study visit for neuropsychiatric testing and phlebotomy. Peripheral blood mononuclear cells were quantified for T and B cell subsets using flow cytometry, and serum cytokine concentrations were measured using multiplex immunoassay. RESULTS: We detected reduced relative numbers of helper T cells and reduced activation of B cells in DLB compared with AD. Additionally, interleukin (IL)-1ß was detected more frequently in DLB and the serum concentration of IL-6 was increased compared with controls. CONCLUSIONS: Peripheral inflammation is altered in DLB compared with AD, with T cell subset analysis supporting a possible shift towards senescence of the adaptive immune system in DLB. Furthermore, there is a proinflammatory signature of serum cytokines in DLB. Identification of this unique peripheral immunophenotype in DLB could guide development of an immune-based biomarker and direct future work exploring potential immune modulation as a novel treatment.
Assuntos
Doença de Alzheimer/imunologia , Linfócitos B/imunologia , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Doença por Corpos de Lewy/imunologia , Monócitos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/fisiopatologia , Estudos de Casos e Controles , Citocinas/imunologia , Feminino , Citometria de Fluxo , Humanos , Imunoensaio , Imunofenotipagem , Doença por Corpos de Lewy/fisiopatologia , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Testes NeuropsicológicosRESUMO
BACKGROUND: Although several studies link high levels of IL-6 and soluble IL-6 receptor (sIL-6R) to asthma severity and decreased lung function, the role of IL-6 trans-signaling (IL-6TS) in asthmatic patients is unclear. OBJECTIVE: We sought to explore the association between epithelial IL-6TS pathway activation and molecular and clinical phenotypes in asthmatic patients. METHODS: An IL-6TS gene signature obtained from air-liquid interface cultures of human bronchial epithelial cells stimulated with IL-6 and sIL-6R was used to stratify lung epithelial transcriptomic data (Unbiased Biomarkers in Prediction of Respiratory Disease Outcomes [U-BIOPRED] cohorts) by means of hierarchical clustering. IL-6TS-specific protein markers were used to stratify sputum biomarker data (Wessex cohort). Molecular phenotyping was based on transcriptional profiling of epithelial brushings, pathway analysis, and immunohistochemical analysis of bronchial biopsy specimens. RESULTS: Activation of IL-6TS in air-liquid interface cultures reduced epithelial integrity and induced a specific gene signature enriched in genes associated with airway remodeling. The IL-6TS signature identified a subset of patients with IL-6TS-high asthma with increased epithelial expression of IL-6TS-inducible genes in the absence of systemic inflammation. The IL-6TS-high subset had an overrepresentation of frequent exacerbators, blood eosinophilia, and submucosal infiltration of T cells and macrophages. In bronchial brushings Toll-like receptor pathway genes were upregulated, whereas expression of cell junction genes was reduced. Sputum sIL-6R and IL-6 levels correlated with sputum markers of remodeling and innate immune activation, in particular YKL-40, matrix metalloproteinase 3, macrophage inflammatory protein 1ß, IL-8, and IL-1ß. CONCLUSIONS: Local lung epithelial IL-6TS activation in the absence of type 2 airway inflammation defines a novel subset of asthmatic patients and might drive airway inflammation and epithelial dysfunction in these patients.
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Asma/imunologia , Biomarcadores/metabolismo , Células Epiteliais/fisiologia , Inflamação/imunologia , Interleucina-6/metabolismo , Pulmão/fisiologia , Escarro/metabolismo , Adulto , Remodelação das Vias Aéreas , Células Cultivadas , Estudos de Coortes , Estudos Transversais , Regulação da Expressão Gênica , Humanos , Masculino , Fenótipo , Receptores de Interleucina-6/metabolismo , Hipersensibilidade Respiratória , Transdução de Sinais , TranscriptomaRESUMO
In pregnancy, maternal physiology is subject to considerable adaptations, including alterations in cardiovascular and metabolic function as well as development of immunological tolerance towards the fetus. In an oocyte donation pregnancy, the fetus is fully allogeneic towards the mother, since it carries both oocyte donor antigens and paternal antigens. Therefore, oocyte donation pregnancies result in an immunologically challenging pregnancy, which is reflected by a higher-than-normal risk to develop pre-eclampsia. Based on the allogeneic conditions in oocyte donation pregnancies, we hypothesized that this situation may translate into alterations in concentration of stable readouts of constituents of the reactive species interactome (RSI) compared to normal pregnancies, especially serum free thiols, nitric oxide (NO) and hydrogen sulfide (H2S) related metabolites. Indeed, total free thiol levels and nitrite (NO2-) concentrations were significantly lower whereas protein-bound NO and sulfate (SO42-) concentrations were significantly higher in both oocyte donation and naturally conceived pregnancies complicated by pre-eclampsia. The increased concentrations of nitrite observed in uncomplicated oocyte donation pregnancies suggest that endothelial NO production is compensatorily enhanced to lower vascular tone. More research is warranted on the role of the RSI and bioenergetic status in uncomplicated oocyte donation pregnancies and oocyte donation pregnancies complicated by pre-eclampsia.
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Óxido Nítrico/metabolismo , Doação de Oócitos/efeitos adversos , Pré-Eclâmpsia/metabolismo , Compostos de Sulfidrila/metabolismo , Adulto , Estudos de Casos e Controles , Feminino , Fertilização in vitro , Humanos , Sulfeto de Hidrogênio , Idade Materna , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Adulto JovemRESUMO
Non-typeable Haemophilus influenzae (NTHi) is the most common pathogen in primary ciliary dyskinesia (PCD) patients. We hypothesised that abnormal ciliary motility and low airway nitric oxide (NO) levels on airway epithelial cells from PCD patients might be permissive for NTHi colonisation and biofilm development.We used a primary epithelial cell co-culture model to investigate NTHi infection. Primary airway epithelial cells from PCD and non-PCD patients were differentiated to ciliation using an air-liquid interface culture and then co-cultured with NTHi.NTHi adherence was greater on PCD epithelial cells compared to non-PCD cells (p<0.05) and the distribution of NTHi on PCD epithelium showed more aggregated NTHi in biofilms (p<0.001). Apart from defective ciliary motility, PCD cells did not significantly differ from non-PCD epithelial cells in the degree of ciliation and epithelial integrity or in cytokine, LL-37 and NO production. Treatment of PCD epithelia using exogenous NO and antibiotic significantly reduced NTHi viability in biofilms compared with antibiotic treatment alone.Impaired ciliary function was the primary defect in PCD airway epithelium underlying susceptibility to NTHi biofilm development compared with non-PCD epithelium. Although NO responses were similar, use of targeted NO with antibiotics enhanced killing of NTHi in biofilms, suggesting a novel therapeutic approach.
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Células Epiteliais/microbiologia , Infecções por Haemophilus/fisiopatologia , Síndrome de Kartagener/microbiologia , Óxido Nítrico/farmacologia , Adolescente , Adulto , Antibacterianos/farmacologia , Aderência Bacteriana , Proteínas de Bactérias/metabolismo , Biofilmes/crescimento & desenvolvimento , Estudos de Casos e Controles , Criança , Pré-Escolar , Citocinas/metabolismo , Feminino , Haemophilus influenzae/patogenicidade , Haemophilus influenzae/fisiologia , Humanos , Síndrome de Kartagener/fisiopatologia , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Adulto JovemRESUMO
INTRODUCTION: Previous investigations have demonstrated that major depression is associated with particular patterns of cytokine signalling. The primary aim of this study was to examine peripheral pro-inflammatory and anti-inflammatory cytokines and immune balance in Generalised Anxiety Disorder (GAD). METHODS: A case-controlled cross-sectional study design was employed: 54 patients with GAD and 64 healthy controls were recruited. Participants completed self-report measures of anxiety and depression. Two pro-inflammatory and two anti-inflammatory cytokines were measured using multiplex technology. RESULTS: Case-control logistic regression analyses revealed significant differences in serum levels of IL-10, TNF-α, and IFN-γ between GAD and control groups after adjusting for age, gender, body mass index, smoking and alcohol consumption: these group differences were independent of the presence or degree of depression. Comparison of pro-inflammatory to anti-inflammatory cytokine ratios indicated that there were significantly higher ratios of TNF-α/IL10, TNF-α/IL4, IFN-γ/IL10, and IFN-γ/IL4 in the GAD group compared to the control group. CONCLUSIONS: This study is the first to investigate both pro- and anti-inflammatory cytokines and their balance in patients with GAD in comparison to healthy controls. The findings indicate a relatively increased pro-inflammatory response and decreased anti-inflammatory response and provide the first demonstration of an altered cytokine balance in GAD. Serum cytokine levels in GAD were independent of the presence of depression.
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Transtornos de Ansiedade/sangue , Citocinas/sangue , Mediadores da Inflamação/sangue , Adolescente , Adulto , Idoso , Ansiedade/sangue , Estudos de Casos e Controles , Estudos Transversais , Depressão/sangue , Feminino , Humanos , Inflamação/sangue , Masculino , Pessoa de Meia-Idade , Autorrelato , Adulto JovemAssuntos
Asma , Hipersensibilidade , Adulto , Asma/diagnóstico , Biomarcadores , Citocinas , HumanosRESUMO
RATIONALE: Asthma is one of the most common chronic diseases worldwide, and individuals with severe asthma experience recurrent exacerbations. Exacerbations are predominantly viral associated and have been linked to defective airway IFN responses. Ascertaining the molecular mechanisms underlying this deficiency is a major research goal to identify new therapeutic targets. OBJECTIVES: We investigated the hypothesis that reduced Toll-like receptor 7 (TLR7)-derived signaling drove the impaired IFN responses to rhinovirus by asthmatic alveolar macrophages (AMs); the molecular mechanisms underlying this deficiency were explored. METHODS: AMs were recovered from bronchoalveolar lavage from healthy subjects and patients with severe asthma. Expression of pattern-recognition receptors and microRNAs was evaluated by quantitative polymerase chain reaction and Western blotting. A TLR7-luciferase reporter construct was created to evaluate binding of microRNAs to the 3' untranslated region of TLR7. IFN production was measured by quantitative polymerase chain reaction and ELISA. MEASUREMENTS AND MAIN RESULTS: The expression of TLR7 was significantly reduced in severe asthma AMs and was associated with reduced rhinovirus and imiquimod-induced IFN responses by these cells compared with healthy AMs. Severe asthma AMs also expressed increased levels of three microRNAs, which we showed were able to directly reduce TLR7 expression. Ex vivo knockdown of these microRNAs restored TLR7 expression with concomitant augmentation of virus-induced IFN production. CONCLUSIONS: In severe asthma, TLR7 deficiency drives impaired innate immune responses to virus by AMs. Blocking a group of microRNAs that are up-regulated in these cells can restore antiviral innate responses, providing a novel approach for therapy in asthma.
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Asma/imunologia , MicroRNAs/imunologia , Receptor 7 Toll-Like/imunologia , Adolescente , Adulto , Idoso , Western Blotting , Líquido da Lavagem Broncoalveolar/imunologia , Feminino , Humanos , Imunidade Inata/imunologia , Macrófagos Alveolares/imunologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Índice de Gravidade de Doença , Adulto JovemRESUMO
BACKGROUND: Disease heterogeneity in patients with severe asthma and its relationship to inflammatory mechanisms remain poorly understood. OBJECTIVE: We aimed to identify and replicate clinicopathologic endotypes based on analysis of blood and sputum parameters in asthmatic patients. METHODS: One hundred ninety-four asthmatic patients and 21 control subjects recruited from 2 separate centers underwent detailed clinical assessment, sputum induction, and phlebotomy. One hundred three clinical, physiologic, and inflammatory parameters were analyzed by using topological data analysis and Bayesian network analysis. RESULTS: Severe asthma was associated with anxiety and depression, obesity, sinonasal symptoms, decreased quality of life, and inflammatory changes, including increased sputum chitinase 3-like protein 1 (YKL-40) and matrix metalloproteinase (MMP) 1, 3, 8, and 12 levels. Topological data analysis identified 6 clinicopathobiologic clusters replicated in both geographic cohorts: young, mild paucigranulocytic; older, sinonasal disease; obese, high MMP levels; steroid resistant TH2 mediated, eosinophilic; mixed granulocytic with severe obstruction; and neutrophilic, low periostin levels, severe obstruction. Sputum IL-5 levels were increased in patients with severe particularly eosinophilic forms, whereas IL-13 was suppressed and IL-17 levels did not differ between clusters. Bayesian network analysis separated clinical features from intricately connected inflammatory pathways. YKL-40 levels strongly correlated with neutrophilic asthma and levels of myeloperoxidase, IL-8, IL-6, and IL-6 soluble receptor. MMP1, MMP3, MMP8, and MMP12 levels were associated with severe asthma and were correlated positively with sputum IL-5 levels but negatively with IL-13 levels. CONCLUSION: In 2 distinct cohorts we have identified and replicated 6 clinicopathobiologic clusters based on blood and induced sputum measures. Our data underline a disconnect between clinical features and underlying inflammation, suggest IL-5 production is relatively steroid insensitive, and highlight the expression of YKL-40 in patients with neutrophilic inflammation and the expression of MMPs in patients with severe asthma.
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Asma/diagnóstico , Asma/metabolismo , Proteína 1 Semelhante à Quitinase-3/metabolismo , Metaloproteinases da Matriz/metabolismo , Adulto , Idoso , Asma/tratamento farmacológico , Teorema de Bayes , Biomarcadores , Estudos de Casos e Controles , Citocinas/metabolismo , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Inibidores de Metaloproteinases de Matriz/metabolismo , Pessoa de Meia-Idade , Testes de Função Respiratória , Fatores de Risco , Índice de Gravidade de Doença , Escarro/metabolismo , Adulto JovemRESUMO
OBJECTIVE: Whilst the exact cause of chronic rhinosinusitis (CRS) remains elusive, it is clear that both inflammation and remodelling are key disease processes. Environmental fungi have been linked to airway inflammation in CRS; however, their role in the pathogenesis of this condition remains controversial. The current consensus suggests that whilst fungi may not be directly causative, it is likely that CRS patients have deficits in their innate and potentially acquired immunity, which in turn may modify their ability to react to fungi. This study used a nasal polyp explant tissue stimulation model to study the inflammatory and remodelling responses related to challenge with common airborne fungal species. METHODS: Ex vivo nasal polyp tissue from six well phenotyped CRSwNP patients undergoing functional endoscopic sinus surgery was stimulated with 1, 10 and 100 µg/ml of Alternaria alternata, Aspergillus niger, Cladosporium sphaerospermum and Penicillium notatum and compared with unchallenged polyp tissue as control. Enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of pro-inflammatory cytokines interleukin-6 (IL-6), granulocyte macrophage colony stimulating factor (GM-CSF) and tumour necrosis factor-α (TNF-α); and pro-remodelling cytokines transforming growth factor-b1 (TGF-b1), and basic fibroblast growth factor (bFGF) in the polyp supernatant. RESULTS: Aspergillus niger stimulation increased pro-inflammatory cytokines TNF-α, GM-CSF and IL-6 whilst having little effect on the remodelling cytokines bFGF and TGF-b1. In contrast, stimulation with Cladosporium sphaerospermum, Alternaria alternata and Penicillium notatum reduced pro-inflammatory cytokines TNF-α and IL-6, but induced a dose-dependent increase in remodelling cytokines TGF-b1 and bFGF. CONCLUSIONS: This study shows that common airborne fungi induce species-specific effects on the upper airway inflammatory and remodelling responses. These findings provide further immunological evidence of a disease-modifying role for fungi in CRS.
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Remodelação das Vias Aéreas , Citocinas/metabolismo , Interações Hospedeiro-Patógeno , Sinusite/microbiologia , Alternaria/fisiologia , Aspergillus niger/fisiologia , Cladosporium/fisiologia , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Penicillium chrysogenum/fisiologia , Projetos Piloto , Sinusite/metabolismoRESUMO
BACKGROUND: Asthma is characterized pathologically by structural changes in the airway, termed airway remodeling. These changes are associated with worse long-term clinical outcomes and have been attributed to eosinophilic inflammation. In vitro studies indicate, however, that the compressive mechanical forces that arise during bronchoconstriction may induce remodeling independently of inflammation. We evaluated the influence of repeated experimentally induced bronchoconstriction on airway structural changes in patients with asthma. METHODS: We randomly assigned 48 subjects with asthma to one of four inhalation challenge protocols involving a series of three challenges with one type of inhaled agent presented at 48-hour intervals. The two active challenges were with either a dust-mite allergen (which causes bronchoconstriction and eosinophilic inflammation) or methacholine (which causes bronchoconstriction without eosinophilic inflammation); the two control challenges (neither of which causes bronchoconstriction) were either saline alone or albuterol followed by methacholine (to control for nonbronchoconstrictor effects of methacholine). Bronchial-biopsy specimens were obtained before and 4 days after completion of the challenges. RESULTS: Allergen and methacholine immediately induced similar levels of bronchoconstriction. Eosinophilic inflammation of the airways increased only in the allergen group, whereas both the allergen and the methacholine groups had significant airway remodeling not seen in the two control groups. Subepithelial collagen-band thickness increased by a median of 2.17 µm in the allergen group (interquartile range [IQR], 0.70 to 3.67) and 1.94 µm in the methacholine group (IQR, 0.37 to 3.24) (P<0.001 for the comparison of the two challenge groups with the two control groups); periodic acid-Schiff staining of epithelium (mucus glands) also increased, by a median of 2.17 percentage points in the allergen group (IQR, 1.03 to 4.77) and 2.13 percentage points in the methacholine group (IQR, 1.14 to 7.96) (P=0.003 for the comparison with controls). There were no significant differences between the allergen and methacholine groups. CONCLUSIONS: Bronchoconstriction without additional inflammation induces airway remodeling in patients with asthma. These findings have potential implications for management.
Assuntos
Asma/fisiopatologia , Brônquios/fisiologia , Broncoconstrição/fisiologia , Adulto , Albuterol/farmacologia , Animais , Asma/patologia , Brônquios/patologia , Testes de Provocação Brônquica , Broncoconstrição/efeitos dos fármacos , Broncodilatadores/farmacologia , Broncoscopia , Eosinófilos , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Humanos , Masculino , Cloreto de Metacolina/farmacologia , Pyroglyphidae/imunologia , Espirometria , Adulto JovemRESUMO
BACKGROUND: Adolescence is a period of change, which coincides with disease remission in a significant proportion of subjects with childhood asthma. There is incomplete understanding of the changing characteristics underlying different adolescent asthma transitions. We undertook pathophysiological characterization of transitional adolescent asthma phenotypes in a longitudinal birth cohort. METHODS: The Isle of Wight Birth Cohort (N = 1456) was reviewed at 1, 2, 4, 10 and 18-years. Characterization included questionnaires, skin tests, spirometry, exhaled nitric oxide, bronchial challenge and (in a subset of 100 at 18-years) induced sputum. Asthma groups were "never asthma" (no asthma since birth), "persistent asthma" (asthma at age 10 and 18), "remission asthma" (asthma at age 10 but not at 18) and "adolescent-onset asthma" (asthma at age 18 but not at age 10). RESULTS: Participants whose asthma remitted during adolescence had lower bronchial reactivity (odds ratio (OR) 0.30; CI 0.10 -0.90; p = 0.03) at age 10 plus greater improvement in lung function (forced expiratory flow 25-75% gain: 1.7 L; 1.0-2.9; p = 0.04) compared to persistent asthma by age 18. Male sex (0.3; 0.1-0.7; p < 0.01) and lower acetaminophen use (0.4; 0.2-0.8; p < 0.01) independently favoured asthma remission, when compared to persistent asthma. Asthma remission had a lower total sputum cell count compared to never asthma (31.5 [25-75 centiles] 12.9-40.4) vs. 47.0 (19.5-181.3); p = 0.03). Sputum examination in adolescent-onset asthma showed eosinophilic airway inflammation (3.0%, 0.7-6.6), not seen in persistent asthma (1.0%, 0-3.9), while remission group had the lowest sputum eosinophil count (0.3%, 0-1.4) and lowest eosinophils/neutrophils ratio of 0.0 (Interquartile range: 0.1). CONCLUSION: Asthma remission during adolescence is associated with lower initial BHR and greater gain in small airways function, while adolescent-onset asthma is primarily eosinophilic.
Assuntos
Asma/fisiopatologia , Pulmão/fisiopatologia , Adolescente , Idade de Início , Asma/diagnóstico , Asma/epidemiologia , Asma/imunologia , Criança , Pré-Escolar , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Lactente , Modelos Logísticos , Pulmão/imunologia , Masculino , Análise Multivariada , Razão de Chances , Fenótipo , Prognóstico , Indução de Remissão , Testes de Função Respiratória , Fatores de Risco , Índice de Gravidade de Doença , Reino Unido/epidemiologiaRESUMO
BACKGROUND: Studies on the capability of cerebrospinal fluid neurofilament light chain (cNfL) to predict multiple sclerosis (MS) conversion in clinically isolated syndromes have yielded varying results. OBJECTIVES: To expand our understanding of cNfL in optic neuritis (ON) and investigate whether incorporating cNfL into the 2017 McDonald criteria could accelerate the diagnosis of MS in patients with ON. METHODS: cNfL was measured in diagnostic samples from 74 patients with verified ON. MS was diagnosed using the 2017 McDonald criteria with a minimum observation time of two years from ON onset. RESULTS: 20.5% of 44 MS-converters did not fulfil the 2017 McDonald criteria at ON onset. A doubling of cNfL was associated with 207% (74%-514%) higher odds of MS (p = 0.00042, adjusted for age). Fulfilment of ≥ 1 MRI criterion for dissemination in space (DIS) and presence of brain contrast-enhancing lesions were associated with higher cNfL. Furthermore, cNfL correlated with inter-eye differences in retinal nerve fiber layer (RNFL) thickness (Spearman's ρ = 0.46, p = 8 × 10-5). Incorporating cNfL ≥ 906 pg/mL as a substitute for either dissemination in time or one MRI criterion for DIS increased the sensitivity (90.9% vs. 79.6%) and accuracy (91.9% vs. 87.8%), but also reduced the specificity (93.3% vs. 100%) of the 2017 McDonald criteria. CONCLUSION: cNfL was related to MS diagnostic parameters and the degree of RNFL swelling. Clinical use of cNfL may aid in identification of ON patients with increased risk of MS until larger studies have elaborated on the potential loss of specificity if used diagnostically.
RESUMO
BACKGROUND: Tissue factor (TF), a primary initiator of blood coagulation, also plays a pivotal role in angiogenesis. TF expression in the airways is associated with asthma, a disease characterized in part by subepithelial angiogenesis. OBJECTIVES: To determine potential sources of TF and the mechanisms of its availability in the lung microenvironment. METHODS: Normal human bronchial epithelial cells grown in air-liquid interface culture were subjected to a compressive stress of 30 cm H(2)O; this is comparable to that generated in the airway epithelium during bronchoconstriction in asthma. Conditioned media and cells were harvested to measure TF mRNA and TF protein. We also tested bronchoalveolar lavage fluid and airway biopsies from asthmatic patients and healthy controls for TF. RESULTS: TF mRNA was upregulated 2.2-fold after 3 hours of stress compared with unstressed cells. Intracellular and secreted TF proteins were enhanced 1.6-fold and more than 50-fold, respectively, compared with those of control cells after the onset of compression. The amount of TF in the bronchoalveolar lavage fluid from patients with asthma was found at mean concentrations that were 5 times greater than those of healthy controls. Immunohistochemical staining of endobronchial biopsies identified epithelial localization of TF with increased expression in asthma. Exosomes isolated from the conditioned media of normal human bronchial epithelial cells and the bronchoalveolar lavage fluid of asthmatic subjects by ultracentrifugation contained TF. CONCLUSIONS: Our in vitro and in vivo studies show that mechanically stressed bronchial epithelial cells are a source of secreted TF and that exosomes are potentially a key carrier of the TF signal.