546 results found
Singanayagam A, Glanville N, Girkin J, et al., 2018, Corticosteroid suppression of antiviral immunity increases bacterial loads and mucus production in COPD exacerbations, Nature Communications, Vol: 9, ISSN: 2041-1723
Inhaled corticosteroids (ICS) have limited efficacy in reducing chronic obstructive pulmonary disease (COPD) exacerbations and increase pneumonia risk, through unknown mechanisms. Rhinoviruses precipitate most exacerbations and increase susceptibility to secondary bacterial infections. Here, we show that the ICS fluticasone propionate (FP) impairs innate and acquired antiviral immune responses leading to delayed virus clearance and previously unrecognised adverse effects of enhanced mucus, impaired antimicrobial peptide secretion and increased pulmonary bacterial load during virus-induced exacerbations. Exogenous interferon-β reverses these effects. FP suppression of interferon may occur through inhibition of TLR3- and RIG-I virus-sensing pathways. Mice deficient in the type I interferon-α/β receptor (IFNAR1−/−) have suppressed antimicrobial peptide and enhanced mucin responses to rhinovirus infection. This study identifies type I interferon as a central regulator of antibacterial immunity and mucus production. Suppression of interferon by ICS during virus-induced COPD exacerbations likely mediates pneumonia risk and raises suggestion that inhaled interferon-β therapy may protect.
Dunning J, Blankley S, Hoang LT, et al., 2018, Progression of whole-blood transcriptional signatures from interferon-induced to neutrophil-associated patterns in severe influenza, Nature Immunology, ISSN: 1529-2916
Transcriptional profiles and host-response biomarkers are used increasingly to investigate the severity, subtype and pathogenesis of disease. We now describe whole-blood mRNA signatures and concentrations of local and systemic immunological mediators in 131 adults hospitalized with influenza, from whom extensive clinical and investigational data were obtained by MOSAIC investigators. Signatures reflective of interferon-related antiviral pathways were common up to day 4 of symptoms in patients who did not require mechanical ventilator support; in those who needed mechanical ventilation, an inflammatory, activated-neutrophil and cell-stress or death (‘bacterial’) pattern was seen, even early in disease. Identifiable bacterial co-infection was not necessary for this ‘bacterial’ signature but was able to enhance its development while attenuating the early ‘viral’ signature. Our findings emphasize the importance of timing and severity in the interpretation of host responses to acute viral infection and identify specific patterns of immune-system activation that might enable the development of novel diagnostic and therapeutic tools for severe influenza.
Custovic A, Belgrave D, Lin L, et al., 2018, Cytokine responses to rhinovirus and development of asthma, allergic sensitization and respiratory infections during childhood, American Journal of Respiratory and Critical Care Medicine, Vol: 197, Pages: 1265-1274, ISSN: 1073-449X
BACKGROUND: Immunophenotypes of anti-viral responses, and their relationship with asthma, allergy and lower respiratory tract infections (LRTIs) are poorly understood. We characterized multiple cytokine responses of peripheral-blood mononuclear cells to rhinovirus stimulation, and their relationship with clinical outcomes. METHODS: In a population-based birth cohort, we measured 28 cytokines post-stimulation with rhinovirus-16 in 307 children aged 11 years. We used machine learning to identify patterns of cytokine responses, and related these patterns to clinical outcomes using longitudinal models. We also ascertained phytohaemagglutinin-induced TH2-cytokine responses [PHA-TH2]. RESULTS: We identified six clusters of children based on their rhinovirus-16 responses, which were differentiated by the expression of four cytokine/chemokine groups: interferon-related-(IFN); pro-inflammatory-(Inflam); TH2-chemokine-(TH2-chem); regulatory-(Reg). Clusters differed in their clinical characteristics. Children with IFNmodInflamhighestTH2-chemhighestReghighestrhinovirus-16-induced pattern had PHA-TH2lowresponse, and a very low asthma risk (OR:0.08 [95%CI 0.01-0.81], P=0.03). Two clusters had high risk of asthma and allergic sensitization, but with different trajectories from infancy to adolescence. The IFNlowestInflamhighTH2-chemlowRegmodcluster exhibited PHA-TH2lowestresponse, and was associated with early-onset asthma and sensitization, and the highest risk of asthma exacerbations (1.37 [1.07-1.76], P=0.014) and LRTI hospitalizations (2.40 [1.26-4.58], P=0.008) throughout childhood. In contrast, cluster with IFNhighestInflammodTH2-chemmodReghighrhinovirus-16-cytokine pattern was characterized by PHA-TH2highestresponse, and a low prevalence of asthma/sensitization in infancy which increased sharply to become the highest among all clusters by adolescence (but with low risk of asthma exacerbations). CONCLUSIONS: Early-onset troublesome asthma with early-life sensitization, later-
Mousnier A, Bell AS, Swieboda DP, et al., 2018, Fragment-derived inhibitors of human N-myristoyltransferase block capsid assembly and replication of the common cold virus, Nature Chemistry, Vol: 10, Pages: 599-606, ISSN: 1755-4330
Rhinoviruses are the pathogens most often responsible for the common cold, and are a frequent cause of exacerbations in asthma, chronic obstructive pulmonary disease and cystic fibrosis. Here we report discovery of IMP-1088, a picomolar dual inhibitor of the human N-myristoyltransferases NMT1 and NMT2, and use it to demonstrate that pharmacological inhibition of host cell N-myristoylation rapidly and completely prevents rhinoviral replication without inducing cytotoxicity. Identification of cooperative binding between weak-binding fragments led to rapid inhibitor optimization through fragment reconstruction, structure-guided fragment linking, and conformational control over linker geometry. We show that inhibition of co-translational myristoylation of a specific virus-encoded protein (VP0) by IMP-1088 potently blocks a key step in viral capsid assembly, delivering low nanomolar antiviral activity against multiple rhinovirus strains, poliovirus and foot-and-mouth disease virus, and protection of cells against virus-induced killing, highlighting the potential of host myristoylation as a drug target in picornaviral infections.
Ghebre MA, Pang PH, Diver S, et al., 2018, Biological exacerbation clusters demonstrate asthma and COPD overlap with distinct mediator and microbiome profiles., Journal of Allergy and Clinical Immunology, ISSN: 0091-6749
BACKGROUND: Exacerbations of asthma and chronic obstructive pulmonary disease (COPD) are heterogeneous. OBJECTIVE: We sought to investigate the sputum cellular, mediator, and microbiome profiles of both asthma and COPD exacerbations. METHODS: Patients with severe asthma or moderate-to-severe COPD were prospectively recruited to a single centre. Sputum mediators were available in 32 asthma and 73 COPD patients assessed at exacerbation. Biologic clusters were determined using factor and cluster analyses on a panel of sputum mediators. Patterns of clinical parameters, sputum mediators, and microbiome communities were assessed across the identified clusters. RESULTS: The asthma and COPD patients had different clinical characteristics and inflammatory profiles, but similar microbial ecology. Three exacerbation biologic clusters were identified. Cluster 1 was COPD predominant, with 27 COPD and 7 asthma patients exhibiting elevated blood and sputum neutrophil counts, proinflammatory mediators (IL-1β, IL-6, IL-6R, TNFα, TNF-R1, TNF-R2, and VEGF), and proportion of the bacterial phylum Proteobacteria. Cluster 2 had 10 asthma and 17 COPD patients with elevated blood and sputum eosinophil counts, Type 2 (T2) mediators (IL-5, IL-13, CCL13, CCL17, and CCL26), and proportion of the bacterial phylum Bacteroidetes. Cluster 3 had 15 asthma and 29 COPD subjects with elevated Type 1 (T1) mediators (CXCL10, CXCL11, and IFN-ϒ) and proportions of phyla Actinobacteria and Firmicutes. CONCLUSIONS: A biologic clustering approach revealed three subgroups of asthma and COPD exacerbations each with different percentages of overlapping asthma and COPD patients. The sputum mediator and microbiome profiles were distinct between clusters. CLINICAL IMPLICATIONS: Sputum mediator and microbiome profiling can determine the distinct and overlapping asthma and COPD biologic exacerbation clusters, highlighting the heterogeneity of these exacerbations.
Zhu J, Message SD, Mallia P, et al., Bronchial mucosal Interferon-α/β and pattern recognition receptor expression in experimental rhinovirus-induced asthma exacerbations, Journal of Allergy and Clinical Immunology, ISSN: 0091-6749
BACKGROUND: The innate immune system senses viral infection via pattern recognition receptors (PRRs) leading to type I interferon (IFN) production: their roles in rhinovirus (RV)-induced asthma exacerbations in vivo are uncertain. OBJECTIVES: To compare bronchial mucosal type I IFN and PRR expression at baseline and following RV infection in atopic asthmatic and control subjects. METHODS: Immunohistochemistry was used to detect expression of IFN-α, IFN-β and the PRRs, toll-like receptor (TLR)-3, melanoma-differentiation-associated gene-5 (MDA-5) and retinoic-acid-inducible protein-I (RIG-I) in bronchial biopsies from 10 atopic asthmatics and 15 non-asthmatic non-atopic controls at baseline and on day four and six weeks following RV infection. RESULTS: We observed IFN-α/β deficiency in bronchial epithelium at three time points in asthma in vivo. Lower epithelial IFN-α/β expression was related to greater virus load, worse airway symptoms, airway hyperresponsiveness (AHR) and reductions in lung function during RV infection. We found lower frequencies of bronchial subepithelial monocytes/macrophages expressing IFN-α/β in asthma during infection. IFN deficiency at baseline was not accompanied by deficient PRR expression in asthma. Both epithelial and subepithelial PRR expression was induced during RV infection. RV infection increased numbers of subepithelial IFN/PRRs-expressing inflammatory cells were related to greater virus load, AHR and reductions in lung function. CONCLUSIONS: Bronchial epithelial IFN-α/β expression and numbers of subepithelial IFN-α/β-expressing monocytes/macrophages during infection were both deficient in asthma. Lower epithelial IFN-α/β expression was associated with adverse clinical outcomes following RV infection in vivo. Increases in subepithelial cells expressing IFN/PRRs during infection were also related to greater virus load/illness severity.
Silkoff PE, Flavin S, Gordon R, et al., 2018, Toll-like receptor 3 blockade in rhinovirus-induced experimental asthma exacerbations: a randomized controlled study, Journal of Allergy and Clinical Immunology, Vol: 141, Pages: 1220-1230, ISSN: 0091-6749
BACKGROUND: Human rhinoviruses (HRVs) commonly precipitate asthma exacerbations. Toll-like receptor 3, an innate pattern recognition receptor, is triggered by HRV, driving inflammation that can worsen asthma. OBJECTIVE: We sought to evaluate an inhibitory mAb to Toll-like receptor 3, CNTO3157, on experimental HRV-16 inoculation in healthy subjects and asthmatic patients. METHODS: In this double-blind, multicenter, randomized, parallel-group study in North America and Europe, healthy subjects and patients with mild-to-moderate stable asthma received single or multiple doses of CNTO3157 or placebo, respectively, and were then inoculated with HRV-16 within 72 hours. All subjects were monitored for respiratory symptoms, lung function, and nasal viral load. The primary end point was maximal decrease in FEV1 during 10 days after inoculation. RESULTS: In asthmatic patients (n = 63) CNTO3157 provided no protection against FEV1 decrease (least squares mean: CNTO3157 [n = 30] = -7.08% [SE, 8.15%]; placebo [n = 25] = -5.98% [SE, 8.56%]) or symptoms after inoculation. In healthy subjects (n = 12) CNTO3157 versus placebo significantly attenuated upper (P = .03) and lower (P = .02) airway symptom scores, with area-under-the-curve increases of 9.1 (15.1) versus 34.9 (17.6) and 13.0 (18.4) versus 50.4 (25.9) for the CNTO3157 (n = 8) and placebo (n = 4) groups, respectively, after inoculation. All of the severe and 4 of the nonserious asthma exacerbations occurred while receiving CNTO3157. CONCLUSION: In summary, CNTO3157 was ineffective in attenuating the effect of HRV-16 challenge on lung function, asthma control, and symptoms in asthmatic patients but suppressed cold symptoms in healthy subjects. Other approaches, including blockade of multiple pathways or antiviral agents, need to be sought for this high unmet medical need.
McErlean P, Kelly A, Dhariwal J, et al., 2018, Genome-wide profiling of an enhancer-associated histone modification reveals the influence of asthma on the epigenome of the airway epithelium., Biorxiv
Asthma is a chronic airway disease driven by complex genetic-environmental interactions. The role of epigenetic modifications in bronchial epithelial cells (BECs) in asthma is poorly understood. We undertook genome-wide profiling of the enhancer-associated histone modification H3K27ac in BECs from people with asthma and healthy controls. We identified 49,903 regions exhibiting differential H3K27ac enrichment in asthma, clustered at genes associated with type-2-high asthma (CLCA1) and epithelial processes (EMT). Asthma dramatically influenced the BEC enhancer landscape and we identified asthma-associated Super-Enhancers encompassing genes encoding transcription factors (TP63) and enzymes regulating lipid metabolism (NOX4). We integrated published protein, epigenomic and transcriptomic datasets and identified epithelium-specific transcription factors associated with H3K27ac in asthma (TP73) and dynamic relationships between asthma-associated changes in H3K27ac, DNA methylation, genetic susceptibility and transcriptional profiles. Finally, we used a CRISPR-based approach to recapitulate the H3K27ac-asthma landscape in vitro and provide proof of principal that asthma-associated gene expression (SERPINB2) is driven in part by aberrant histone acetylation, validating the combination of genome-wide and epigenome-editing approaches in deciphering the molecular mechanisms underlying asthma pathogenesis.
Moskwa S, Piotrowski W, Marczak J, et al., 2018, Innate Immune Response to Viral Infections in Primary Bronchial Epithelial Cells is Modified by the Atopic Status of Asthmatic Patients, ALLERGY ASTHMA & IMMUNOLOGY RESEARCH, Vol: 10, Pages: 144-154, ISSN: 2092-7355
PurposeIn order to gain an insight into determinants of reported variability in immune responses to respiratory viruses in human bronchial epithelial cells (HBECs) from asthmatics, the responses of HBEC to viral infections were evaluated in HBECs from phenotypically heterogeneous groups of asthmatics and in healthy controls.MethodsHBECs were obtained during bronchoscopy from 10 patients with asthma (6 atopic and 4 non-atopic) and from healthy controls (n=9) and grown as undifferentiated cultures. HBECs were infected with parainfluenza virus (PIV)-3 (MOI 0.1) and rhinovirus (RV)-1B (MOI 0.1), or treated with medium alone. The cell supernatants were harvested at 8, 24, and 48 hours. IFN-α, CXCL10 (IP-10), and RANTES (CCL5) were analyzed by using Cytometric Bead Array (CBA), and interferon (IFN)-β and IFN-λ1 by ELISA. Gene expression of IFNs, chemokines, and IFN-regulatory factors (IRF-3 and IRF-7) was determined by using quantitative PCR.ResultsPIV3 and RV1B infections increased IFN-λ1 mRNA expression in HBECs from asthmatics and healthy controls to a similar extent, and virus-induced IFN-λ1 expression correlated positively with IRF-7 expression. Following PIV3 infection, IP-10 protein release and mRNA expression were significantly higher in asthmatics compared to healthy controls (median 36.03-fold). No differences in the release or expression of RANTES, IFN-λ1 protein and mRNA, or IFN-α and IFN-β mRNA between asthmatics and healthy controls were observed. However, when asthmatics were divided according to their atopic status, HBECs from atopic asthmatics (n=6) generated significantly more IFN-λ1 protein and demonstrated higher IFN-α, IFN-β, and IRF-7 mRNA expressions in response to PIV3 compared to non-atopic asthmatics (n=4) and healthy controls (n=9). In response to RV1B infection, IFN-β mRNA expression was lower (12.39-fold at 24 hours and 19.37-fold at 48 hours) in non-atopic asthmatics com
Delgado-Eckert E, Fuchs O, Kumar N, et al., 2018, Functional phenotypes determined by fluctuation-based clustering of lung function measurements in healthy and asthmatic cohort participants, THORAX, Vol: 73, Pages: 107-115, ISSN: 0040-6376
Dhariwal J, Cameron A, Wong E, et al., 2018, Pulmonary Innate Lymphoid Cell Responses During Rhinovirus-Induced Asthma Exacerbations, American-Academy-of-Allergy-Asthma-and-Immunology / World-Allergy-Organization Joint Congress, Publisher: MOSBY-ELSEVIER, Pages: AB195-AB195, ISSN: 0091-6749
Hanratty CE, Matthews JG, Arron JR, et al., 2018, A randomised pragmatic trial of corticosteroid optimization in severe asthma using a composite biomarker algorithm to adjust corticosteroid dose versus standard care: study protocol for a randomised trial., Trials, Vol: 19, ISSN: 1745-6215
BACKGROUND: Patients with difficult-to-control asthma consume 50-60% of healthcare costs attributed to asthma and cost approximately five-times more than patients with mild stable disease. Recent evidence demonstrates that not all patients with asthma have a typical type 2 (T2)-driven eosinophilic inflammation. These asthmatics have been called 'T2-low asthma' and have a minimal response to corticosteroid therapy. Adjustment of corticosteroid treatment using sputum eosinophil counts from induced sputum has demonstrated reduced severe exacerbation rates and optimized corticosteroid dose. However, it has been challenging to move induced sputum into the clinical setting. There is therefore a need to examine novel algorithms to target appropriate levels of corticosteroid treatment in difficult asthma, particularly in T2-low asthmatics. This study examines whether a composite non-invasive biomarker algorithm predicts exacerbation risk in patients with asthma on high-dose inhaled corticosteroids (ICS) (± long-acting beta agonist) treatment, and evaluates the utility of this composite score to facilitate personalized biomarker-specific titration of corticosteroid therapy. METHODS/DESIGN: Patients recruited to this pragmatic, multi-centre, single-blinded randomised controlled trial are randomly allocated into either a biomarker controlled treatment advisory algorithm or usual care group in a ratio of 4:1. The primary outcome measure is the proportion of patients with any reduction in ICS or oral corticosteroid dose from baseline to week 48. Secondary outcomes include the rate of protocol-defined severe exacerbations per patient per year, time to first severe exacerbation from randomisation, dose of inhaled steroid at the end of the study, cumulative dose of inhaled corticosteroid during the study, proportion of patients on oral corticosteroids at the end of the study, proportion of patients who decline to progress to oral corticosteroids despite composite biomarker s
Ritchie AI, Singanayagam A, Wiater E, et al., 2018, beta(2)-agonists enhance asthma-relevant inflammatory mediators in human airway epithelial cells, American Journal of Respiratory Cell and Molecular Biology, Vol: 58, Pages: 128-132, ISSN: 1044-1549
Dhariwal J, Wong E, Trujillo-Torralbo B, et al., 2018, Poor Baseline Asthma Control Is Associated with Greater Virus Load Following Rhinovirus Infection, International Conference of the American-Thoracic-Society, Publisher: AMER THORACIC SOC, ISSN: 1073-449X
Tang HHF, Teo SM, Belgrave DCM, et al., 2017, Non-parametric mixture models identify trajectories of childhood immune development relevant to asthma and allergy, Publisher: bioRxiv
Events in early life contribute to subsequent risk of asthma; however, the causes and trajectories of childhood wheeze are heterogeneous and do not always result in asthma. Similarly, not all atopic individuals develop wheeze, and vice versa. The reasons for these differences are unclear. Using unsupervised model-based cluster analysis, we identified latent clusters within a prospective birth cohort with deep immunological and respiratory phenotyping. We characterised each cluster in terms of immunological profile and disease risk, and replicated our results in external cohorts from the UK and USA. We discovered three distinct trajectories, one of which is a high-risk "atopic" cluster with increased propensity for allergic diseases throughout childhood. Atopy contributes varyingly to later wheeze depending on cluster membership. Our findings demonstrate the utility of unsupervised analysis in elucidating heterogeneity in asthma pathogenesis and provide a foundation for improving management and prevention of childhood asthma.
Finney LJ, Belchamber K, Kemp S, et al., 2017, HUMAN RHINOVIRUS IMPAIRS PHAGOCYTOSIS OF HAEMOPHILUS INFLUENZAE IN ALVEOLAR MACROPHAGES IN CHRONIC OBSTRUCTIVE PULMONARY DISEASE, Winter Meeting of the British-Thoracic-Society, Publisher: BMJ PUBLISHING GROUP, Pages: A112-A112, ISSN: 0040-6376
Teo SM, Tang HHF, Mok D, et al., 2017, Dynamics of the upper airway microbiome in the pathogenesis of asthma-associated persistent wheeze in preschool children, Biorxiv
Repeated cycles of infection-associated lower airway inflammation drives the pathogenesis of persistent wheezing disease in children. Tracking these events across a birth cohort during their first five years, we demonstrate that >80% of infectious events indeed involve viral pathogens, but are accompanied by a shift in the nasopharyngeal microbiome (NPM) towards dominance by a small range of pathogenic bacterial genera. Unexpectedly, this change in NPM frequently precedes the appearance of viral pathogens and acute symptoms. In non-sensitized children these events are associated only with "transient wheeze" that resolves after age three. In contrast, in children developing early allergic sensitization, they are associated with ensuing development of persistent wheeze, which is the hallmark of the asthma phenotype. This suggests underlying pathogenic interactions between allergic sensitization and anti-bacterial mechanisms.
Toussaint M, Jackson DJ, Swieboda D, et al., 2017, Corrigendum: Host DNA released by NETosis promotes rhinovirus-induced type-2 allergic asthma exacerbation., Nat Med, Vol: 23, Pages: 1384-1384
This corrects the article DOI: 10.1038/nm.4332.
Edwards MR, Strong K, Cameron A, et al., 2017, Viral infections in allergy and immunology: How allergic inflammation influences viral infections and illness, JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY, Vol: 140, Pages: 909-920, ISSN: 0091-6749
Viral respiratory tract infections are associated with asthma inception in early life and asthma exacerbations in older children and adults. Although how viruses influence asthma inception is poorly understood, much research has focused on the host response to respiratory viruses and how viruses can promote; or how the host response is affected by subsequent allergen sensitization and exposure. This review focuses on the innate interferon-mediated host response to respiratory viruses and discusses and summarizes the available evidence that this response is impaired or suboptimal. In addition, the ability of respiratory viruses to act in a synergistic or additive manner with TH2 pathways will be discussed. In this review we argue that these 2 outcomes are likely linked and discuss the available evidence that shows reciprocal negative regulation between innate interferons and TH2 mediators. With the renewed interest in anti-TH2 biologics, we propose a rationale for why they are particularly successful in controlling asthma exacerbations and suggest ways in which future clinical studies could be used to find direct evidence for this hypothesis.
Hellings PW, Fokkens WJ, Bachert C, et al., 2017, Positioning the principles of precision medicine in care pathways for allergic rhinitis and chronic rhinosinusitis - A EUFOREA-ARIA-EPOS-AIRWAYS ICP statement, Allergy, Vol: 72, Pages: 1297-1305, ISSN: 0105-4538
Precision medicine (PM) is increasingly recognized as the way forward for optimizing patient care. Introduced in the field of oncology, it is now considered of major interest in other medical domains like allergy and chronic airway diseases, which face an urgent need to improve the level of disease control, enhance patient satisfaction and increase effectiveness of preventive interventions. The combination of personalized care, prediction of treatment success, prevention of disease and patient participation in the elaboration of the treatment plan is expected to substantially improve the therapeutic approach for individuals suffering from chronic disabling conditions. Given the emerging data on the impact of patient stratification on treatment outcomes, European and American regulatory bodies support the principles of PM and its potential advantage over current treatment strategies. The aim of the current document was to propose a consensus on the position and gradual implementation of the principles of PM within existing adult treatment algorithms for allergic rhinitis (AR) and chronic rhinosinusitis (CRS). At the time of diagnosis, prediction of success of the initiated treatment and patient participation in the decision of the treatment plan can be implemented. The second‐level approach ideally involves strategies to prevent progression of disease, in addition to prediction of success of therapy, and patient participation in the long‐term therapeutic strategy. Endotype‐driven treatment is part of a personalized approach and should be positioned at the tertiary level of care, given the efforts needed for its implementation and the high cost of molecular diagnosis and biological treatment.
Upton N, Jackson DJ, Nikonova AA, et al., 2017, Rhinovirus induction of fractalkine (CX3CL1) in airway and peripheral blood mononuclear cells in asthma, PLoS ONE, Vol: 12, ISSN: 1932-6203
Rhinovirus infection is associated with the majority of asthma exacerbations. The role of fractalkine in anti-viral (type 1) and pathogenic (type 2) responses to rhinovirus infection in allergic asthma is unknown. To determine whether (1) fractalkine is produced in airway cells and in peripheral blood leucocytes, (2) rhinovirus infection increases production of fractalkine and (3) levels of fractalkine differ in asthmatic compared to non-asthmatic subjects. Fractalkine protein and mRNA levels were measured in bronchoalveolar lavage (BAL) cells and peripheral blood mononuclear cells (PBMCs) from non-asthmatic controls (n = 15) and mild allergic asthmatic (n = 15) subjects. Protein levels of fractalkine were also measured in macrophages polarised ex vivo to give M1 (type 1) and M2 (type 2) macrophages and in BAL fluid obtained from mild (n = 11) and moderate (n = 14) allergic asthmatic and non-asthmatic control (n = 10) subjects pre and post in vivo rhinovirus infection. BAL cells produced significantly greater levels of fractalkine than PBMCs. Rhinovirus infection increased production of fractalkine by BAL cells from non-asthmatic controls (P<0.01) and in M1-polarised macrophages (P<0.05), but not in BAL cells from mild asthmatics or in M2 polarised macrophages. Rhinovirus induced fractalkine in PBMCs from asthmatic (P<0.001) and healthy control subjects (P<0.05). Trends towards induction of fractalkine in moderate asthmatic subjects during in vivo rhinovirus infection failed to reach statistical significance. Fractalkine may be involved in both immunopathological and anti-viral immune responses to rhinovirus infection. Further investigation into how fractalkine is regulated across different cell types and into the effect of stimulation including rhinovirus infection is warranted to better understand the precise role of this unique dual adhesion factor and chemokine in immune cell recruitment.
Haldar K, Bafadhel M, Lau K, et al., 2017, Microbiome balance in sputum determined by PCR stratifies COPD exacerbations and shows potential for selective use of antibiotics, PLOS ONE, Vol: 12, ISSN: 1932-6203
Farne HA, Johnston SL, 2017, Immune mechanisms of respiratory viral infections in asthma., Current Opinion in Immunology, Vol: 48, Pages: 31-37, ISSN: 0952-7915
The more severe pathology respiratory viral infections produce in asthma sufferers is a result of a dysregulated immune response. Excess type 2 inflammation is a well-described feature of virally induced asthma exacerbations, with growing evidence that production of antiviral interferons may also be impaired. However, the mechanisms underlying these are little understood. This review summarizes the current understanding and recent discoveries of the cellular and molecular events that follow viral infections in asthma. In particular, we discuss differences in viral sensing and intracellular signalling pathways upstream of interferon induction in asthma, and the role of epithelial-derived cytokines in orchestrating type 2 immunopathology, including type 2 innate lymhpoid cells (ILC2s).
Edwards MR, Walton RP, Jackson DJ, et al., 2017, The potential of anti-infectives and immunomodulators as therapies for asthma and asthma exacerbations., Allergy, Vol: 73, Pages: 50-63, ISSN: 0105-4538
Asthma is responsible for approximately 25,000 deaths annually in Europe despite available medicines that maintain asthma control and reduce asthma exacerbations. Better treatments are urgently needed for the control of chronic asthma and reduction in asthma exacerbations, the major cause of asthma mortality. Much research spanning >20 years shows a strong association between microorganisms including pathogens in asthma onset, severity and exacerbation, yet with the exception of antibiotics, few treatments are available that specifically target the offending pathogens. Recent insights into the microbiome suggest that modulating commensal organisms within the gut or lung may also be a possible way to treat/prevent asthma. The European Academy of Allergy & Clinical Immunology Task Force on Anti-infectives in Asthma was initiated to investigate the potential of anti-infectives and immunomodulators in asthma. This review provides a concise summary of the current literature and aimed to identify and address key questions that concern the use of anti-infectives and both microbe- and host-based immunomodulators and their feasibility for use in asthma.
Vasileiou E, Sheikh A, Butler C, et al., 2017, Effectiveness of influenza vaccines in asthma: a systematic review and meta-analysis, Clinical Infectious Diseases, Vol: 65, Pages: 1388-1395, ISSN: 1058-4838
There is uncertainty about the effectiveness of influenza vaccination in people with asthma and its impact on asthma outcomes, which may contribute to the sub-optimal vaccination rates in people with asthma. This systematic review and meta-analysis involved searching 12 international databases for randomized controlled trials (RCTs) and high quality quasi-experimental and epidemiological studies (1970 to 2016). The risk of bias was low for three included RCTs. The quality of three included observational studies was moderate. The quality of evidence was very low for all study outcomes. Pooled vaccine effectiveness in 1,825 people with asthma from two test-negative design case-control studies was 45% (95% CI 31 to 56) for laboratory-confirmed influenza. Pooled efficacy of live vaccines in reducing influenza was 81% (95% CI 33 to 94). Live vaccine reduced febrile illness by 72% (95% CI 20 to 90). Influenza vaccine prevented 59-78% of asthma attacks leading to emergency visits and/or hospitalizations. For people with asthma influenza vaccination may be effective in both reducing influenza infection and asthma attacks.
Prakash R, Hallett IC, Wong SF, et al., 2017, Cell separation in kiwifruit without development of a specialised detachment zone, BMC PLANT BIOLOGY, Vol: 17, ISSN: 1471-2229
Papadopoulos NG, Androutsopoulou A, Akdis C, et al., 2017, Asthma research in Europe: a transformative agenda for innovation and competitiveness, European Respiratory Journal, Vol: 49, ISSN: 0903-1936
Asthma is highly prevalent, often starting in infancy and persisting throughout life, and is associated with high morbidity and burden. It is a major global health challenge with growing impact, affecting more than 300 million people worldwide and at least 10% of all Europeans . Furthermore, it is the most prevalent long-term condition in children . Approximately 5–10% of asthma cases are so severe that current treatments do not work, and over five million people in the European Union (EU) fall into this category.People with asthma live at risk of life-threatening asthma attacks, leading to at least 500 000 hospitalisations worldwide each year . A European study estimated that unscheduled care and rescue medication accounted for 47% of the total cost-per-patient in infants, 45% in children and 56% in adults . This results in high socio-economic impact, estimated at more than €70 billion annually . This includes the costs of direct primary and hospital healthcare (estimated to be close to €20 billion per annum), costs due to lost productivity (€14 billion) , and the monetised value of disability-adjusted life-years (DALYs) lost (over €38 billion) . Close to 1 million DALYs are lost due to asthma in Europe every year .Despite the fact that the direct and indirect costs of asthma are substantial and continue to rise, asthma remains under-prioritised in the EU research agenda. Only 0.5% of the Seventh Framework Programme (FP7) health research budget was devoted to asthma and chronic obstructive pulmonary disease (COPD) (€30 million) . In comparison, some 5.4 times this amount (over €163 million) was spent on cardiovascular conditions and some 20.6 times (over €618 million) on brain research.Asthma, with its high global prevalence and an associated multi-billion global market for treatments, plus its historical underfunding and the demand for new treatments and diagnostics, represents an enormous opportu
Edwards MR, Saglani S, Schwarze J, et al., 2017, Addressing unmet needs in understanding asthma mechanisms: From the European Asthma Research and Innovation Partnership (EARIP) Work Package (WP)2 collaborators, European Respiratory Journal, Vol: 49, ISSN: 1399-3003
Asthma is a heterogeneous, complex disease with clinical phenotypes that incorporate persistent symptoms and acute exacerbations. It affects many millions of Europeans throughout their education and working lives and puts a heavy cost on European productivity. There is a wide spectrum of disease severity and control. Therapeutic advances have been slow despite greater understanding of basic mechanisms and the lack of satisfactory preventative and disease modifying management for asthma constitutes a significant unmet clinical need. Preventing, treating and ultimately curing asthma requires co-ordinated research and innovation across Europe. The European Asthma Research and Innovation Partnership (EARIP) is an FP7-funded programme which has taken a co-ordinated and integrated approach to analysing the future of asthma research and development. This report aims to identify the mechanistic areas in which investment is required to bring about significant improvements in asthma outcomes.
Toussaint M, Swieboda D, Guedan A, et al., NETosis and associated host DNA orchestrate rhinovirus-induced type 2 allergic asthma exacerbation, Nature Medicine, ISSN: 1546-170X
Respiratory viral infections represent the most common cause of allergic asthma exacerbations. Amplification of type 2 immunity is strongly implicated in asthma exacerbation, but how virus infection boosts type 2 responses during exacerbation is poorly understood. We report a significant correlation between release of host double stranded DNA (dsDNA) following rhinovirus infection and exacerbation of type 2 allergic inflammation and disease severity in patients. In a mouse model, we show that rhinovirus infection triggers neutrophil extracellular traps (NETs) formation and host dsDNA release. We further demonstrate that inhibiting NETosis by blocking neutrophil elastase or degrading NETs with DNase protects mice from type 2 allergic asthma exacerbations. Furthermore, injection of host dsDNA alone is sufficient to recapitulate many features of rhinovirus-induced type 2 immune responses and asthma pathology. Thus, NETosis and host dsDNA contribute to exacerbation pathogenesis and may represent potential targets for novel treatments of rhinovirus-induced asthma exacerbations.
Toussaint M, Jackson DJ, Swieboda D, et al., 2017, Host DNA released by NETosis promotes rhinovirus-induced type-2 allergic asthma exacerbation, NATURE MEDICINE, Vol: 23, Pages: 681-691, ISSN: 1078-8956
Respiratory viral infections represent the most common cause of allergic asthma exacerbations. Amplification of the type-2 immune response is strongly implicated in asthma exacerbation, but how virus infection boosts type-2 responses is poorly understood. We report a significant correlation between the release of host double-stranded DNA (dsDNA) following rhinovirus infection and the exacerbation of type-2 allergic inflammation in humans. In a mouse model of allergic airway hypersensitivity, we show that rhinovirus infection triggers dsDNA release associated with the formation of neutrophil extracellular traps (NETs), known as NETosis. We further demonstrate that inhibiting NETosis by blocking neutrophil elastase or by degrading NETs with DNase protects mice from type-2 immunopathology. Furthermore, the injection of mouse genomic DNA alone is sufficient to recapitulate many features of rhinovirus-induced type-2 immune responses and asthma pathology. Thus, NETosis and its associated extracellular dsDNA contribute to the pathogenesis and may represent potential therapeutic targets of rhinovirus-induced asthma exacerbations.
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