Type I conventional dendritic cells relate to disease severity in virus-induced asthma exacerbations.

RATIONALE: Rhinoviruses are the major precipitant of asthma exacerbations and individuals with asthma experience more severe/prolonged rhinovirus infections. Concurrent viral infection and allergen exposure synergistically increase exacerbation risk. Although dendritic cells orchestrate immune responses to both virus and allergen, little is known about their role in viral asthma exacerbations. OBJECTIVES: To characterize dendritic cell populations present in the lower airways, and to assess whether their numbers are altered in asthma compared to healthy subjects prior to infection and during rhinovirus-16 infection. METHODS: Moderately-severe atopic asthmatic patients and healthy controls were experimentally infected with rhinovirus-16. Bronchoalveolar lavage was collected at baseline, day 3 and day 8 post infection and dendritic cells isolated using fluorescence activated cell sorting. MEASUREMENTS AND MAIN RESULTS: Numbers of type I conventional dendritic cells, which cross prime CD8+ T helper cells and produce innate interferons, were significantly reduced in the lower airways of asthma patients compared to healthy controls at baseline. This reduction was associated serum IgE at baseline and with reduced numbers of CD8+ T helper cells and with increased viral replication, airway eosinophils and reduced lung function during infection. IgE receptor expression on lower airway plasmacytoid dendritic cells was significantly increased in asthma, consistent with a reduced capacity to produce innate interferons. CONCLUSIONS: Reduced numbers of anti-viral type I conventional dendritic cells in asthma are associated with adverse outcomes during rhinovirus infection. This, with increased FcεR1α expression on lower airway plasmacytoid DCs could mediate the more permissive respiratory viral infection observed in asthma patients.

Pulmonary Innate Lymphoid Cell Responses during Rhinovirus-induced Asthma Exacerbations In Vivo: A Clinical Trial.

Rationale: Type 2 innate lymphoid cells (ILC2s) are significant sources of type 2 cytokines, which are implicated in the pathogenesis of asthma and asthma exacerbations. The role of ILC2s in virus-induced asthma exacerbations is not well characterized. Objectives: To characterize pulmonary ILC responses following experimental rhinovirus challenge in patients with moderate asthma and healthy subjects. Methods: Patients with moderate asthma and healthy subjects were inoculated with rhinovirus-16 and underwent bronchoscopy at baseline and at Day 3, and Day 8 after inoculation. Pulmonary ILC1s and ILC2s were quantified in bronchoalveolar lavage using flow cytometry. The ratio of bronchoalveolar lavage ILC2:ILC1 was assessed to determine their relative contributions to the clinical and immune response to rhinovirus challenge. Measurements and Main Results: At baseline, ILC2s were significantly higher in patients with asthma than in healthy subjects. At Day 8, ILC2s significantly increased from baseline in both groups, which was significantly higher in patients with asthma than in healthy subjects (all comparisons P < 0.05). In healthy subjects, ILC1s increased from baseline at Day 3 (P = 0.001), while in patients with asthma, ILC1s increased from baseline at Day 8 (P = 0.042). Patients with asthma had significantly higher ILC2:ILC1 ratios at baseline (P = 0.024) and Day 8 (P = 0.005). Increased ILC2:ILC1 ratio in patients with asthma correlated with clinical exacerbation severity and type 2 cytokines in nasal mucosal lining fluid. Conclusions: An ILC2-predominant inflammatory profile in patients with asthma was associated with increased severity and duration of rhinovirus infection compared with healthy subjects, supporting the potential role of ILC2s in the pathogenesis of virus-induced asthma exacerbations.

Severe Disseminated Infection with Emerging Lineage of Methicillin-Sensitive Staphylococcus aureus.

We report a case of severe disseminated infection in an immunocompetent man caused by an emerging lineage of methicillin-sensitive Staphylococcus aureus clonal complex 398. Genes encoding classic virulence factors were absent. The patient made a slow recovery after multiple surgical interventions and a protracted course of intravenous flucloxacillin.

Identification of novel macrolides with antibacterial, anti-inflammatory and type I and III IFN-augmenting activity in airway epithelium.

BACKGROUND: Exacerbations of asthma and COPD are triggered by rhinoviruses. Uncontrolled inflammatory pathways, pathogenic bacterial burden and impaired antiviral immunity are thought to be important factors in disease severity and duration. Macrolides including azithromycin are often used to treat the above diseases, but exhibit variable levels of efficacy. Inhaled corticosteroids are also readily used in treatment, but may lack specificity. Ideally, new treatment alternatives should suppress unwanted inflammation, but spare beneficial antiviral immunity. METHODS: In the present study, we screened 225 novel macrolides and tested them for enhanced antiviral activity against rhinovirus, as well as anti-inflammatory activity and activity against Gram-positive and Gram-negative bacteria. Primary bronchial epithelial cells were grown from 10 asthmatic individuals and the effects of macrolides on rhinovirus replication were also examined. Another 30 structurally similar macrolides were also examined. RESULTS: The oleandomycin derivative Mac5, compared with azithromycin, showed superior induction (up to 5-fold, EC50 = 5-11 µM) of rhinovirus-induced type I IFNß, type III IFNλ1 and type III IFNλ2/3 mRNA and the IFN-stimulated genes viperin and MxA, yet had no effect on IL-6 and IL-8 mRNA. Mac5 also suppressed rhinovirus replication at 48 h, proving antiviral activity. Mac5 showed antibacterial activity against Gram-positive Streptococcus pneumoniae; however, it did not have any antibacterial properties compared with azithromycin when used against Gram-negative Escherichia coli (as a model organism) and also the respiratory pathogens Pseudomonas aeruginosa and non-typeable Haemophilus influenzae. Further non-toxic Mac5 derivatives were identified with various anti-inflammatory, antiviral and antibacterial activities. CONCLUSIONS: The data support the idea that macrolides have antiviral properties through a mechanism that is yet to be ascertained. We also provide evidence that macrolides can be developed with anti-inflammatory, antibacterial and antiviral activity and show surprising versatility depending on the clinical need.

A text-based conversational agent for asthma support: Mixed-methods feasibility study.

Objective: Millions of people in the UK have asthma, yet 70% do not access basic care, leading to the largest number of asthma-related deaths in Europe. Chatbots may extend the reach of asthma support and provide a bridge to traditional healthcare. This study evaluates 'Brisa', a chatbot designed to improve asthma patients' self-assessment and self-management. Methods: We recruited 150 adults with an asthma diagnosis to test our chatbot. Participants were recruited over three waves through social media and a research recruitment platform. Eligible participants had access to 'Brisa' via a WhatsApp or website version for 28 days and completed entry and exit questionnaires to evaluate user experience and asthma control. Weekly symptom tracking, user interaction metrics, satisfaction measures, and qualitative feedback were utilised to evaluate the chatbot's usability and potential effectiveness, focusing on changes in asthma control and self-reported behavioural improvements. Results: 74% of participants engaged with 'Brisa' at least once. High task completion rates were observed: asthma attack risk assessment (86%), voice recording submission (83%) and asthma control tracking (95.5%). Post use, an 8% improvement in asthma control was reported. User satisfaction surveys indicated positive feedback on helpfulness (80%), privacy (87%), trustworthiness (80%) and functionality (84%) but highlighted a need for improved conversational depth and personalisation. Conclusions: The study indicates that chatbots are effective for asthma support, demonstrated by the high usage of features like risk assessment and control tracking, as well as a statistically significant improvement in asthma control. However, lower satisfaction in conversational flexibility highlights rising expectations for chatbot fluency, influenced by advanced models like ChatGPT. Future health-focused chatbots must balance conversational capability with accuracy and safety to maintain engagement and effectiveness.

Assessing the Feasibility of a Text-Based Conversational Agent for Asthma Support: Protocol for a Mixed Methods Observational Study.

BACKGROUND: Despite efforts, the UK death rate from asthma is the highest in Europe, and 65% of people with asthma in the United Kingdom do not receive the professional care they are entitled to. Experts have recommended the use of digital innovations to help address the issues of poor outcomes and lack of care access. An automated SMS text messaging-based conversational agent (ie, chatbot) created to provide access to asthma support in a familiar format via a mobile phone has the potential to help people with asthma across demographics and at scale. Such a chatbot could help improve the accuracy of self-assessed risk, improve asthma self-management, increase access to professional care, and ultimately reduce asthma attacks and emergencies. OBJECTIVE: The aims of this study are to determine the feasibility and usability of a text-based conversational agent that processes a patient's text responses and short sample voice recordings to calculate an estimate of their risk for an asthma exacerbation and then offers follow-up information for lowering risk and improving asthma control; assess the levels of engagement for different groups of users, particularly those who do not access professional services and those with poor asthma control; and assess the extent to which users of the chatbot perceive it as helpful for improving their understanding and self-management of their condition. METHODS: We will recruit 300 adults through four channels for broad reach: Facebook, YouGov, Asthma + Lung UK social media, and the website Healthily (a health self-management app). Participants will be screened, and those who meet inclusion criteria (adults diagnosed with asthma and who use WhatsApp) will be provided with a link to access the conversational agent through WhatsApp on their mobile phones. Participants will be sent scheduled and randomly timed messages to invite them to engage in dialogue about their asthma risk during the period of study. After a data collection period (28 days), participants will respond to questionnaire items related to the quality of the interaction. A pre- and postquestionnaire will measure asthma control before and after the intervention. RESULTS: This study was funded in March 2021 and started in January 2022. We developed a prototype conversational agent, which was iteratively improved with feedback from people with asthma, asthma nurses, and specialist doctors. Fortnightly reviews of iterations by the clinical team began in September 2022 and are ongoing. This feasibility study will start recruitment in January 2023. The anticipated completion of the study is July 2023. A future randomized controlled trial will depend on the outcomes of this study and funding. CONCLUSIONS: This feasibility study will inform a follow-up pilot and larger randomized controlled trial to assess the impact of a conversational agent on asthma outcomes, self-management, behavior change, and access to care. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/42965.

Prevalence and correlates of herpes simplex virus type-2 infection among men who have sex with men, san francisco, 2008.

BACKGROUND: Most herpes simplex virus type 2 (HSV-2) infections are asymptomatic or unrecognized, so periodic serological surveys are necessary in order to measure the true prevalence of infection, track trends over time, and identify correlates of infection, including coinfection with human immunodeficiency virus (HIV). METHODS: We conducted a community-based, cross-sectional, serological survey among 500 men who have sex with men (MSM) in San Francisco during 2008. RESULTS: The seroprevalence of HSV-2 infection was 26.1% (95% confidence interval [CI], 18.3-33.9), of HIV infection was 18.6% (95% CI, 13.0-24.4), and of HSV-2/HIV coinfection was 12.0% (95% CI, 7.3-16.8; categories not mutually exclusive). HSV-2 prevalence was 3.7 (95% CI, 2.3-5.9) times as high among HIV-infected MSM as among HIV-uninfected MSM. Strong predictors of HSV-2 infection among both HIV-infected and HIV-uninfected MSM were older age and black race. CONCLUSIONS: The prevalence of HSV-2 infection among MSM in San Francisco is similar to that among MSM nationwide and is higher than that among all men nationwide. Prevalence rates are highly disparate among subpopulations of MSM in San Francisco, with the strongest predictors of infection being HIV-positive serostatus, older age, and black race. Primary prevention of HSV-2, particularly among populations at the highest risk for infection with HSV-2 or HIV, should remain a major public health goal to reduce the substantial morbidity caused by both of these infections.

Qualitative Study of Practices and Challenges of Stepping Down Asthma Medication in Primary Care Across the UK.

BACKGROUND: Guidelines recommend that asthma treatment should be stepped down to the minimally effective dose that achieves symptom control to prevent medication side effects and reduce unnecessary costs. Little is known about the practice of stepping down and the challenges in primary care, where most asthma patients are managed. OBJECTIVE: To explore views, experiences, barriers and ideas, of doctors, nurses and pharmacists working in primary care, related to step down of asthma medication. METHODS: Primary care practitioners from across the UK participated in a survey and/or semi-structured interview. Questions explored four main areas: how asthma medication is reviewed, views on asthma guidelines, perceived barriers faced by healthcare workers and facilitators of stepping down. Qualitative content analysis enabled data coding of interview transcripts to identify major themes. RESULTS: A total of 274 participants responded to the survey, 29 participated in an interview (12 doctors, 9 nurses, and 8 pharmacists), working in GP practices from across the UK. Nearly half of the survey participants infrequently step down asthma medication (doctors=42.7%, nurses=46.3%). Four major themes related to barriers to stepping down were (i) lack of awareness of the need to step down, (ii) inertia to step down, driven by low confidence in ability, fear of consequences, and concern for who is responsible for stepping down, (iii) self-efficacy of ability to step down, influenced by lack of clear, applied guidance and limited training, and (iv) feasibility of step down, driven by a lack of systematic acceptance of stepping down and time. Strategies proposed to reduce overtreatment included education and training, improved gathering of evidence and guidance, and integrating step down into routine asthma care. CONCLUSION: Failure to implement this guideline recommendation into everyday asthma management is influenced by several contributing factors. Future directions should include addressing evidence gaps, implementing clear and practical guidance, integration of step-down assessment into the asthma review, and education of professionals and patients.

Respiratory specialists working in different ways: Development of a GP hotline and respiratory support service during the COVID-19 pandemic.

Integration of primary and secondary care for the management of respiratory disease is a long-held ambition. Here, we describe how respiratory specialists at a large NHS trust, working with primary care clinicians in the area, set up a GP hotline and respiratory support service in response to the COVID-19 pandemic, with the aim of enhancing delivery of care to patients in this unprecedented time. Working across traditional organisational boundaries in this way confers benefits to patients and clinicians, illustrating the value of new, integrated models of care.

Epitope-specific airway-resident CD4+ T cell dynamics during experimental human RSV infection.

BACKGROUNDRespiratory syncytial virus (RSV) is an important cause of acute pulmonary disease and one of the last remaining major infections of childhood for which there is no vaccine. CD4+ T cells play a key role in antiviral immunity, but they have been little studied in the human lung.METHODSHealthy adult volunteers were inoculated i.n. with RSV A Memphis 37. CD4+ T cells in blood and the lower airway were analyzed by flow cytometry and immunohistochemistry. Bronchial soluble mediators were measured using quantitative PCR and MesoScale Discovery. Epitope mapping was performed by IFN-γ ELISpot screening, confirmed by in vitro MHC binding.RESULTSActivated CD4+ T cell frequencies in bronchoalveolar lavage correlated strongly with local C-X-C motif chemokine 10 levels. Thirty-nine epitopes were identified, predominantly toward the 3' end of the viral genome. Five novel MHC II tetramers were made using an immunodominant EFYQSTCSAVSKGYL (F-EFY) epitope restricted to HLA-DR4, -DR9, and -DR11 (combined allelic frequency: 15% in Europeans) and G-DDF restricted to HLA-DPA1*01:03/DPB1*02:01 and -DPA1*01:03/DPB1*04:01 (allelic frequency: 55%). Tetramer labeling revealed enrichment of resident memory CD4+ T (Trm) cells in the lower airway; these Trm cells displayed progressive differentiation, downregulation of costimulatory molecules, and elevated CXCR3 expression as infection evolved.CONCLUSIONSHuman infection challenge provides a unique opportunity to study the breadth of specificity and dynamics of RSV-specific T-cell responses in the target organ, allowing the precise investigation of Trm recognizing novel viral antigens over time. The new tools that we describe enable precise tracking of RSV-specific CD4+ cells, potentially accelerating the development of effective vaccines.TRIAL REGISTRATIONClinicalTrials.gov NCT02755948.FUNDINGMedical Research Council, Wellcome Trust, National Institute for Health Research.

Azithromycin for Acute Exacerbations of Asthma : The AZALEA Randomized Clinical Trial.

Importance: Guidelines recommend against antibiotic use to treat asthma attacks. A study with telithromycin reported benefit, but adverse reactions limit its use. Objective: To determine whether azithromycin added to standard care for asthma attacks in adults results in clinical benefit. Design, Setting, and Participants: The Azithromycin Against Placebo in Exacerbations of Asthma (AZALEA) randomized, double-blind, placebo-controlled clinical trial, a United Kingdom-based multicenter study in adults requesting emergency care for acute asthma exacerbations, ran from September 2011 to April 2014. Adults with a history of asthma for more than 6 months were recruited within 48 hours of presentation to medical care with an acute deterioration in asthma control requiring a course of oral and/or systemic corticosteroids. Interventions: Azithromycin 500 mg daily or matched placebo for 3 days. Main Outcomes and Measures: The primary outcome was diary card symptom score 10 days after randomization, with a hypothesized treatment effect size of -0.3. Secondary outcomes were diary card symptom score, quality-of-life questionnaires, and lung function changes, all between exacerbation and day 10, and time to a 50% reduction in symptom score. Results: Of 4582 patients screened at 31 centers, 199 of a planned 380 were randomized within 48 hours of presentation. The major reason for nonrecruitment was receipt of antibiotics (2044 [44.6%] screened patients). Median time from presentation to drug administration was 22 hours (interquartile range, 14-28 hours). Exacerbation characteristics were well balanced across treatment arms and centers. The primary outcome asthma symptom scores were mean (SD), 4.14 (1.38) at exacerbation and 2.09 (1.71) at 10 days for the azithromycin group and 4.18 (1.48) and 2.20 (1.51) for the placebo group, respectively. Using multilevel modeling, there was no significant difference in symptom scores between azithromycin and placebo at day 10 (difference, -0.166; 95% CI, -0.670 to 0.337), nor on any day between exacerbation and day 10. No significant between-group differences were observed in quality-of-life questionnaires or lung function between exacerbation and day 10, or in time to 50% reduction in symptom score. Conclusions and Relevance: In this randomized population, azithromycin treatment resulted in no statistically or clinically significant benefit. For each patient randomized, more than 10 were excluded because they had already received antibiotics. Trial Registration: clinicaltrials.gov Identifier: NCT01444469.

RSV-specific airway resident memory CD8+ T cells and differential disease severity after experimental human infection.

In animal models, resident memory CD8+ T (Trm) cells assist in respiratory virus elimination but their importance in man has not been determined. Here, using experimental human respiratory syncytial virus (RSV) infection, we investigate systemic and local virus-specific CD8+ T-cell responses in adult volunteers. Having defined the immunodominance hierarchy, we analyse phenotype and function longitudinally in blood and by serial bronchoscopy. Despite rapid clinical recovery, we note surprisingly extensive lower airway inflammation with persistent viral antigen and cellular infiltrates. Pulmonary virus-specific CD8+ T cells display a CD69+CD103+ Trm phenotype and accumulate to strikingly high frequencies into convalescence without continued proliferation. While these have a more highly differentiated phenotype, they express fewer cytotoxicity markers than in blood. Nevertheless, their abundance before infection correlates with reduced symptoms and viral load, implying that CD8+ Trm cells in the human lung can confer protection against severe respiratory viral disease when humoral immunity is overcome.

The role of macrolides in asthma: current evidence and future directions.

Macrolides, such as clarithromycin and azithromycin, possess antimicrobial, immunomodulatory, and potential antiviral properties. They represent a potential therapeutic option for asthma, a chronic inflammatory disorder characterised by airway hyper-responsiveness that leads to recurrent episodes of wheezing, breathlessness, chest tightness, and coughing. Results from clinical trials, however, have been contentious. The findings could be confounded by many factors, including the heterogeneity of asthma, treatment duration, dose, and differing outcome measures. Recent evidence suggests improved effectiveness of macrolides in patients with sub-optimally controlled severe neutrophilic asthma and in asthma exacerbations. We examine the evidence from clinical trials and discuss macrolide properties and their relevance to the pathophysiology of asthma. At present, the use of macrolides in chronic asthma or acute exacerbations is not justified. Further work, including proteomic, genomic, and microbiome studies, will advance our knowledge of asthma phenotypes, and help to identify a macrolide-responsive subgroup. Future clinical trials should target this subgroup and place emphasis on clinically relevant outcomes such as asthma exacerbations.

The establishment of a Canadian network emergency response contractors

The need a strong network of compétent emergency response Contractors (ERCs) to components Canada's capability to deal with transportation emergencies involving dangerous goods has long been recognized by the private and public sector. In 1992, under the auspices of the Emergency Response Committee of the canadia Chemical producers' Association (CCPA), representative for the chemical industry, the ERCs community, the road and rail carriers, and transport Canada formed a Task force led to the publication in April, 1993 of the ERCs survey which provided descriptive information on the classes of dangerous goods, container types, modes of transport, and response activities of eleven (11) ERCs. In April, 1995 a revised edition of the survey was published, which included the results of a self - assessment program (AU)