Interferon-epsilon is a novel regulator of NK cell responses in the uterus.

The uterus is a unique mucosal site where immune responses are balanced to be permissive of a fetus, yet protective against infections. Regulation of natural killer (NK) cell responses in the uterus during infection is critical, yet no studies have identified uterine-specific factors that control NK cell responses in this immune-privileged site. We show that the constitutive expression of IFNε in the uterus plays a crucial role in promoting the accumulation, activation, and IFNγ production of NK cells in uterine tissue during Chlamydia infection. Uterine epithelial IFNε primes NK cell responses indirectly by increasing IL-15 production by local immune cells and directly by promoting the accumulation of a pre-pro-like NK cell progenitor population and activation of NK cells in the uterus. These findings demonstrate the unique features of this uterine-specific type I IFN and the mechanisms that underpin its major role in orchestrating innate immune cell protection against uterine infection.

TACTICS VR Stroke Telehealth Virtual Reality Training for Health Care Professionals Involved in Stroke Management at Telestroke Spoke Hospitals: Module Design and Implementation Study.

BACKGROUND: Stroke management in rural areas is more variable and there is less access to reperfusion therapies, when compared with metropolitan areas. Delays in treatment contribute to worse patient outcomes. To improve stroke management in rural areas, health districts are implementing telestroke networks. The New South Wales Telestroke Service provides neurologist-led telehealth to 23 rural spoke hospitals aiming to improve treatment delivery and patient outcomes. The training of clinical staff was identified as a critical aspect for the successful implementation of this service. Virtual reality (VR) training has not previously been used in this context. OBJECTIVE: We sought to develop an evidence-based VR training module specifically tailored for stroke telehealth. During implementation, we aimed to assess the feasibility of workplace deployment and collected feedback from spoke hospital staff involved in stroke management on training acceptability and usability as well as perceived training impact. METHODS: The TACTICS VR Stroke Telehealth application was developed with subject matter experts. During implementation, both quantitative and qualitative data were documented, including VR use and survey feedback. VR hardware was deployed to 23 rural hospitals, and use data were captured via automated Wi-Fi transfer. At 7 hospitals in a single local health district, staff using TACTICS VR were invited to complete surveys before and after training. RESULTS: TACTICS VR Stroke Telehealth was deployed to rural New South Wales hospitals starting on April 14, 2021. Through August 20, 2023, a total of 177 VR sessions were completed. Survey respondents (n=20) indicated a high level of acceptability, usability, and perceived training impact (eg, accuracy and knowledge transfer; mean scores 3.8-4.4; 5=strongly agree). Furthermore, respondents agreed that TACTICS VR increased confidence (13/18, 72%), improved understanding (16/18, 89%), and improved awareness (17/18, 94%) regarding stroke telehealth. A comparison of matched pre- and posttraining responses revealed that training improved the understanding of telehealth workflow practices (after training: mean 4.2, SD 0.6; before training: mean 3.2, SD 0.9; P<.001), knowledge on accessing stroke telehealth (mean 4.1, SD 0.6 vs mean 3.1, SD 1.0; P=.001), the awareness of stroke telehealth (mean 4.1, SD 0.6 vs mean 3.4, SD 0.9; P=.03), ability to optimally communicate with colleagues (mean 4.2, SD 0.6 vs mean 3.7, SD 0.9; P=.02), and ability to make improvements (mean 4.0, SD 0.6 vs mean 3.5, SD 0.9; P=.03). Remote training and deployment were feasible, and limited issues were identified, although uptake varied widely (0-66 sessions/site). CONCLUSIONS: TACTICS VR Stroke Telehealth is a new VR application specifically tailored for stroke telehealth workflow training at spoke hospitals. Training was considered acceptable, usable, and useful and had positive perceived training impacts in a real-world clinical implementation context. Additional work is required to optimize training uptake and integrate training into existing education pathways.

Evaluation of a Virtual Reality Platform to Train Stress Management Skills for a Defense Workforce: Multisite, Mixed Methods Feasibility Study.

BACKGROUND: Psychological stress-related injuries within first-responder organizations have created a need for the implementation of effective stress management training. Most stress management training solutions have limitations associated with scaled adoption within the workforce. For instance, those that are effective in civilian populations often do not align with the human performance culture embedded within first-responder organizations. Programs involving expert-led instructions that are high in quality are often expensive. OBJECTIVE: This study sought to evaluate a tailored stress management training platform within the existing training schedule of the Australian Defense Force (ADF). The platform, known as Performance Edge (PE), is a novel virtual reality (VR) and biofeedback-enabled stress management skills training platform. Focusing on practical training of well-established skills and strategies, the platform was designed to take advantage of VR technology to generate an immersive and private training environment. This study aimed to assess the feasibility of delivering the VR platform within the existing group-based training context and intended training population. In this setting, the study further aimed to collect data on critical predictors of user acceptance and technology adoption in education, including perceived usability, usefulness, and engagement, while also assessing training impacts. METHODS: This study used a mixed methods, multisite approach to collect observational, self-reported, and biometric data from both training staff and trainers within a real-world "on-base" training context in the ADF. Validated scales include the Presence Questionnaire and User Engagement Scale for perceived usefulness, usability, and engagement, as well as the State Mindfulness Scale and Relaxation Inventory, to gain insights into immediate training impacts for specific training modules. Additional surveys were specifically developed to assess implementation feedback, intention to use skills, and perceived training impact and value. RESULTS: PE training was delivered to 189 ADF trainees over 372 training sessions. The platform was easy to use at an individual level and was feasible to deliver in a classroom setting. Trainee feedback consistently showed high levels of engagement and a sense of presence with the training content and environment. PE is overall perceived as an effective and useful training tool. Self-report and objective indices confirmed knowledge improvement, increased skill confidence, and increased competency after training. Specific training elements resulted in increased state mindfulness, increased physical relaxation, and reduced breathing rate. The ability to practice cognitive strategies in a diverse, private, and immersive training environment while in a group setting was highlighted as particularly valuable. CONCLUSIONS: This study found the VR-based platform (PE) to be a feasible stress management training solution for group-based training delivery in a defense population. Furthermore, the intended end users, both trainers and trainees, perceive the platform to be usable, useful, engaging, and effective for training, suggesting end-user acceptance and potential for technology adoption.

Correction: Evaluation of a Virtual Reality Platform to Train Stress Management Skills for a Defense Workforce: Multisite, Mixed Methods Feasibility Study.

[This corrects the article DOI: 10.2196/46368.].

Upper Respiratory Tract OC43 Infection Model for Investigating Airway Immune-Modifying Therapies.

Respiratory virus infections initiate and transmit from the upper respiratory tract (URT). Coronaviruses, including OC43, are a major cause of respiratory infection and disease. Failure to mount an effective antiviral immune response in the nasal mucosa increases the risk of severe disease and person-to-person transmission, highlighting the need for URT infection models to support the development of nasal treatments that improve coronavirus antiviral immunity. We aimed to determine if OC43 productively infected the mouse URT and would therefore be a suitable model to assess the efficacy and mechanism of action of nasal-targeting immune-modifying treatments. We administered OC43 via intranasal inoculation to wild-type Balb/c mice and assessed virus airway tropism (by comparing total respiratory tract vs. URT-only virus exposure) and characterized infection-induced immunity by quantifying specific antiviral cytokines and performing gene array assessment of immune genes. We then assessed the effect of immune-modulating therapies, including an immune-stimulating TLR2/6 agonist (INNA-X) and the immune-suppressing corticosteroid fluticasone propionate (FP). OC43 replicated in nasal respiratory epithelial cells, with peak viral RNA observed 2 days after infection. Prophylactic treatment with INNA-X accelerated expression of virus-induced IFN-λ and IFN-stimulated genes. In contrast, intranasal FP treatment increased nasal viral load by 2.4 fold and inhibited virus-induced IFN and IFN-stimulated gene expression. Prior INNA-X treatment reduced the immune-suppressive effect of FP. We demonstrate that the mouse nasal epithelium is permissive to OC43 infection and strengthen the evidence that TLR2 activation is a ß-coronavirus innate immune determinant and therapeutic target.

Comparing approaches for selection, development, and deployment of extended reality (XR) teaching applications: A case study at The University of Newcastle Australia.

The use of extended reality (XR) technology in education offers many advantages for transferring knowledge and practical skills training at the higher education level. As a result, many Universities over the past 5 + years have undertaken pilot programs to both develop XR content and assess how to best implement it within existing teaching and learning systems. Unfortunately, very few of these efforts have included structured evaluation or documentation. As such, limited published evidence exists to inform processes and approaches that may assist or hinder broad scale implementation. This leads many Universities to unnecessarily commit significant time and resources to testing identical or similar approaches, resulting in repeated identification of the same or similar challenges. In response to this situation, The University of Newcastle, Australia decided to systematically document the approach for selection, development and implementation of four new virtual-reality (VR) teaching applications. The current paper contains a detailed intrinsic case study, outlining the process and critical elements that shaped the selection of suitable teaching content, software development, hardware solutions and implementation. Details are provided on how decisions were made, what components were considered helpful, challenges identified, and important lessons outlined. These findings will be useful to organisations and individuals as they look to develop pathways and processes to integrate XR technology, particularly within their existing training and educational frameworks. Supplementary Information: The online version contains supplementary material available at 10.1007/s10639-022-11364-2.

Toll-like receptor-agonist-based therapies for respiratory viral diseases: thinking outside the cell.

Respiratory virus infections initiate in the upper respiratory tract (URT). Innate immunity is critical for initial control of infection at this site, particularly in the absence of mucosal virus-neutralising antibodies. If the innate immune response is inadequate, infection can spread to the lower respiratory tract (LRT) causing community-acquired pneumonia (as exemplified by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)/coronavirus disease 2019). Vaccines for respiratory viruses (influenza and SARS-CoV-2) leverage systemic adaptive immunity to protect from severe lung disease. However, the URT remains vulnerable to infection, enabling viral transmission and posing an ongoing risk of severe disease in populations that lack effective adaptive immunity.Innate immunity is triggered by host cell recognition of viral pathogen-associated molecular patterns via molecular sensors such as Toll-like receptors (TLRs). Here we review the role of TLRs in respiratory viral infections and the potential of TLR-targeted treatments to enhance airway antiviral immunity to limit progression to severe LRT disease and reduce person-to-person viral transmission. By considering cellular localisation and antiviral mechanisms of action and treatment route/timing, we propose that cell surface TLR agonist therapies are a viable strategy for preventing respiratory viral diseases by providing immediate, durable pan-viral protection within the URT.

TACTICS - Trial of Advanced CT Imaging and Combined Education Support for Drip and Ship: evaluating the effectiveness of an 'implementation intervention' in providing better patient access to reperfusion therapies: protocol for a non-randomised controlled stepped wedge cluster trial in acute stroke.

INTRODUCTION: Stroke reperfusion therapies, comprising intravenous thrombolysis (IVT) and/or endovascular thrombectomy (EVT), are best practice treatments for eligible acute ischemic stroke patients. In Australia, EVT is provided at few, mainly metropolitan, comprehensive stroke centres (CSC). There are significant challenges for Australia's rural and remote populations in accessing EVT, but improved access can be facilitated by a 'drip and ship' approach. TACTICS (Trial of Advanced CT Imaging and Combined Education Support for Drip and Ship) aims to test whether a multicomponent, multidisciplinary implementation intervention can increase the proportion of stroke patients receiving EVT. METHODS AND ANALYSIS: This is a non-randomised controlled, stepped wedge trial involving six clusters across three Australian states. Each cluster comprises one CSC hub and a minimum of three primary stroke centre (PSC) spokes. Hospitals will work in a hub and spoke model of care with access to a multislice CT scanner and CT perfusion image processing software (MIStar, Apollo Medical Imaging). The intervention, underpinned by behavioural theory and technical assistance, will be allocated sequentially, and clusters will move from the preintervention (control) period to the postintervention period. PRIMARY OUTCOME: Proportion of all stroke patients receiving EVT, accounting for clustering. SECONDARY OUTCOMES: Proportion of patients receiving IVT at PSCs, proportion of treated patients (IVT and/or EVT) with good (modified Rankin Scale (mRS) score 0-2) or poor (mRS score 5-6) functional outcomes and European Quality of Life Scale scores 3 months postintervention, proportion of EVT-treated patients with symptomatic haemorrhage, and proportion of reperfusion therapy-treated patients with good versus poor outcome who presented with large vessel occlusion at spokes. ETHICS AND DISSEMINATION: Ethical approval has been obtained from the Hunter New England Human Research Ethics Committee (18/09/19/4.13, HREC/18/HNE/241, 2019/ETH01238). Trial results will be disseminated widely through published manuscripts, conference presentations and at national and international platforms regardless of whether the trial was positive or neutral. TRIAL REGISTRATION NUMBER: ACTRN12619000750189; UTNU1111-1230-4161.

Development and Pilot Implementation of TACTICS VR: A Virtual Reality-Based Stroke Management Workflow Training Application and Training Framework.

Delays in acute stroke treatment contribute to severe and negative impacts for patients and significant healthcare costs. Variability in clinical care is a contributor to delayed treatment, particularly in rural, regional and remote (RRR) areas. Targeted approaches to improve stroke workflow processes improve outcomes, but numerous challenges exist particularly in RRR settings. Virtual reality (VR) applications can provide immersive and engaging training and overcome some existing training barriers. We recently initiated the TACTICS trial, which is assessing a "package intervention" to support advanced CT imaging and streamlined stroke workflow training. As part of the educational component of the intervention we developed TACTICS VR, a novel VR-based training application to upskill healthcare professionals in optimal stroke workflow processes. In the current manuscript, we describe development of the TACTICS VR platform which includes the VR-based training application, a user-facing website and an automated back-end data analytics portal. TACTICS VR was developed via an extensive and structured scoping and consultation process, to ensure content was evidence-based, represented best-practice and is tailored for the target audience. Further, we report on pilot implementation in 7 Australian hospitals to assess the feasibility of workplace-based VR training. A total of 104 healthcare professionals completed TACTICS VR training. Users indicated a high level of usability, acceptability and utility of TACTICS VR, including aspects of hardware, software design, educational content, training feedback and implementation strategy. Further, users self-reported increased confidence in their ability to make improvements in stroke management after TACTICS VR training (post-training mean ± SD = 4.1 ± 0.6; pre-training = 3.6 ± 0.9; 1 = strongly disagree, 5 = strongly agree). Very few technical issues were identified, supporting the feasibility of this training approach. Thus, we propose that TACTICS VR is a fit-for-purpose, evidence-based training application for stroke workflow optimisation that can be readily deployed on-site in a clinical setting.

T-helper 22 cells develop as a distinct lineage from Th17 cells during bacterial infection and phenotypic stability is regulated by T-bet.

CD4+ T-helper 22 (Th22) cells are a phenotypically distinct lymphocyte subset that produces high levels of interleukin (IL)-22 without co-production of IL-17A. However, the developmental origin and lineage classification of Th22 cells, their interrelationship to Th17 cells, and potential for plasticity at sites of infection and inflammation remain largely undefined. An improved understanding of the mechanisms underpinning the outgrowth of Th22 cells will provide insights into their regulation during homeostasis, infection, and disease. To address this knowledge gap we generated 'IL-17A-fate-mapping IL-17A/IL-22 reporter transgenic mice' and show that Th22 cells develop in the gastrointestinal tract and lung during bacterial infection without transitioning via an Il17a-expressing intermediate, although in some compartments alternative transition pathways exist. Th22-cell development was not dependent on T-bet; however, this transcription factor functioned as a promiscuous T-cell-intrinsic regulator of IL-17A and IL-22 production, in addition to regulating the outgrowth, phenotypic stability, and plasticity of Th22 cells. Thus, we demonstrate that at sites of mucosal bacterial infection Th22 cells develop as a distinct lineage independently of Th17 cells; though both lineages exhibit bidirectional phenotypic flexibility within infected tissues and their draining lymph nodes, and that T-bet plays a critical regulatory role in Th22-cell function and identity.

Development of a modular stress management platform (Performance Edge VR) and a pilot efficacy trial of a bio-feedback enhanced training module for controlled breathing.

This paper describes the conceptual design of a virtual reality-based stress management training tool and evaluation of the initial prototype in a pilot efficacy study. Performance Edge virtual-reality (VR) was co-developed with the Australian Defence Force (ADF) to address the need for practical stress management training for ADF personnel. The VR application is biofeedback-enabled and contains key stress management techniques derived from acceptance and commitment and cognitive behavioural therapy in a modular framework. End-user-provided feedback on usability, design, and user experience was positive, and particularly complimentary of the respiratory biofeedback functionality. Training of controlled breathing delivered across 3 sessions increased participants' self-reported use of breath control in everyday life and progressively improved controlled breathing skills (objectively assessed as a reduction in breathing rate and variability). Thus the data show that a biofeedback-enabled controlled breathing protocol delivered through Performance Edge VR can produce both behaviour change and objective improvement in breathing metrics. These results confirm the validity of Performance Edge VR platform, and its Controlled Breathing module, as a novel approach to tailoring VR-based applications to train stress management skills in a workplace setting.

Severe asthma assessment, management and the organisation of care in Australia and New Zealand: expert forum roundtable meetings.

Severe asthma imposes a significant burden on individuals, families and the healthcare system. Treatment is complex, due to disease heterogeneity, comorbidities and complexity in care pathways. New approaches and treatments improve health outcomes for people with severe asthma. However, emerging multidimensional and targeted treatment strategies require a reorganisation of asthma care. Consensus is required on how reorganisation should occur and what areas require further research. The Centre of Excellence in Severe Asthma convened three forums between 2015 and 2018, hosting experts from Australia, New Zealand and the UK. The forums were complemented by a survey of clinicians involved in the management of people with severe asthma. We sought to: (i) identify areas of consensus among experts; (ii) define activities and resources required for the implementation of findings into practice; and (iii) identify specific priority areas for future research. Discussions identified areas of unmet need including assessment and diagnosis of severe asthma, models of care and treatment pathways, add-on treatment approaches and patient perspectives. We recommend development of education and training activities, clinical resources and standards of care documents, increased stakeholder engagement and public awareness campaigns and improved access to infrastructure and funding. Further, we propose specific future research to inform clinical decision-making and develop novel therapies. A concerted effort is required from all stakeholders (including patients, healthcare professionals and organisations and government) to integrate new evidence-based practices into clinical care and to advance research to resolve questions relevant to improving outcomes for people with severe asthma.

Rhinovirus-induced CCL17 and CCL22 in Asthma Exacerbations and Differential Regulation by STAT6.

The interplay of type-2 inflammation and antiviral immunity underpins asthma exacerbation pathogenesis. Virus infection induces type-2 inflammation-promoting chemokines CCL17 and CCL22 in asthma; however, mechanisms regulating induction are poorly understood. By using a human rhinovirus (RV) challenge model in human airway epithelial cells in vitro and mice in vivo, we assessed mechanisms regulating CCL17 and CCL22 expression. Subjects with mild to moderate asthma and healthy volunteers were experimentally infected with RV and airway CCL17 and CCL22 protein quantified. In vitro airway epithelial cell- and mouse-RV infection models were then used to define STAT6- and NF-κB-mediated regulation of CCL17 and CCL22 expression. Following RV infection, CCL17 and CCL22 expression was higher in asthma, which differentially correlated with clinical and immunological parameters. Air-liquid interface-differentiated primary epithelial cells from donors with asthma also expressed higher levels of RV-induced CCL22. RV infection boosted type-2 cytokine-induced STAT6 activation. In epithelial cells, type-2 cytokines and STAT6 activation had differential effects on chemokine expression, increasing CCL17 and suppressing CCL22, whereas NF-κB promoted expression of both chemokines. In mice, RV infection activated pulmonary STAT6, which was required for CCL17 but not CCL22 expression. STAT6-knockout mice infected with RV expressed increased levels of NF-κB-regulated chemokines, which was associated with rapid viral clearance. Therefore, RV-induced upregulation of CCL17 and CCL22 was mediated by NF-κB activation, whereas expression was differentially regulated by STAT6. Together, these findings suggest that therapeutic targeting of type-2 STAT6 activation alone will not block all inflammatory pathways during RV infection in asthma.

TLR2-mediated innate immune priming boosts lung anti-viral immunity.

BACKGROUND: We assessed whether Toll-like receptor (TLR)2 activation boosts the innate immune response to rhinovirus infection, as a treatment strategy for virus-induced respiratory diseases. METHODS: We employed treatment with a novel TLR2 agonist (INNA-X) prior to rhinovirus infection in mice, and INNA-X treatment in differentiated human bronchial epithelial cells derived from asthmatic-donors. We assessed viral load, immune cell recruitment, cytokines, type I and III interferon (IFN) production, as well as the lung tissue and epithelial cell immune transcriptome. RESULTS: We show, in vivo, that a single INNA-X treatment induced innate immune priming characterised by low-level IFN-λ, Fas ligand, chemokine expression and airway lymphocyte recruitment. Treatment 7 days before infection significantly reduced lung viral load, increased IFN-ß/λ expression and inhibited neutrophilic inflammation. Corticosteroid treatment enhanced the anti-inflammatory effects of INNA-X. Treatment 1 day before infection increased expression of 190 lung tissue immune genes. This tissue gene expression signature was absent with INNA-X treatment 7 days before infection, suggesting an alternate mechanism, potentially via establishment of immune cell-mediated mucosal innate immunity. In vitro, INNA-X treatment induced a priming response defined by upregulated IFN-λ, chemokine and anti-microbial gene expression that preceded an accelerated response to infection enriched for nuclear factor (NF)-κB-regulated genes and reduced viral loads, even in epithelial cells derived from asthmatic donors with intrinsic delayed anti-viral immune response. CONCLUSION: Airway epithelial cell TLR2 activation induces prolonged innate immune priming, defined by early NF-κB activation, IFN-λ expression and lymphocyte recruitment. This response enhanced anti-viral innate immunity and reduced virus-induced airway inflammation.

Airway Epithelial Cell Immunity Is Delayed During Rhinovirus Infection in Asthma and COPD.

Respiratory viral infections, particularly those caused by rhinovirus, exacerbate chronic respiratory inflammatory diseases, such as asthma and chronic obstructive pulmonary disease (COPD). Airway epithelial cells are the primary site of rhinovirus replication and responsible of initiating the host immune response to infection. Numerous studies have reported that the anti-viral innate immune response (including type I and type III interferon) in asthma is less effective or deficient leading to the conclusion that epithelial innate immunity is a key determinant of disease severity during a rhinovirus induced exacerbation. However, deficient rhinovirus-induced epithelial interferon production in asthma has not always been observed. We hypothesized that disparate in vitro airway epithelial infection models using high multiplicity of infection (MOI) and lacking genome-wide, time course analyses have obscured the role of epithelial innate anti-viral immunity in asthma and COPD. To address this, we developed a low MOI rhinovirus model of differentiated primary epithelial cells obtained from healthy, asthma and COPD donors. Using genome-wide gene expression following infection, we demonstrated that gene expression patterns are similar across patient groups, but that the kinetics of induction are delayed in cells obtained from asthma and COPD donors. Rhinovirus-induced innate immune responses were defined by interferons (type-I, II, and III), interferon response factors (IRF1, IRF3, and IRF7), TLR signaling and NF-κB and STAT1 activation. Induced gene expression was evident at 24 h and peaked at 48 h post-infection in cells from healthy subjects. In contrast, in cells from donors with asthma or COPD induction was maximal at or beyond 72-96 h post-infection. Thus, we propose that propensity for viral exacerbations of asthma and COPD relate to delayed (rather than deficient) expression of epithelial cell innate anti-viral immune genes which in turns leads to a delayed and ultimately more inflammatory host immune response.

Severe Asthma Toolkit: an online resource for multidisciplinary health professionals-needs assessment, development process and user analytics with survey feedback.

OBJECTIVES: Severe asthma imposes a significant burden on individuals, families and the healthcare system. New treatment and management approaches are emerging as effective options for severe asthma. Translating new knowledge to multidisciplinary healthcare professionals is a priority. We developed 'The Severe Asthma Toolkit' (https://toolkit.severeasthma.org.au) to increase awareness of severe asthma, provide evidence-based resources and support decisionmaking by healthcare providers. SETTING: Roundtable discussions and a survey of Australians clinicians were conducted to determine clinician preferences, format and content for a severe asthma resource. PARTICIPANTS: A reference group from stakeholder and consumer bodies and severe asthma experts provided advice and feedback. A multidisciplinary team of international experts was engaged to develop content. Written content was based on up-to-date literature. Peer and editorial review were performed to finalise content and inform web design. Website design focused on user experience, navigation, engagement, interactivity and tailoring of content for a clinical audience. RESULTS: A web-based resource was developed. Roundtable discussions and a needs assessment survey identified the need for dedicated severe asthma management resources to support skills training. The end-product, which launched 26 March 2018, includes an overview of severe asthma, diagnosis and assessment, management, medications, comorbidities, living with severe asthma, establishing a clinic, paediatrics/adolescents and clinical resources. Analytics indicate access by users worldwide (32 169 users from 169 countries). User survey results (n=394) confirm access by the target audience (72% health professionals), who agreed the toolkit increased their knowledge (73%) and confidence in managing severe asthma (66%), and 75% are likely to use the resource in clinic. CONCLUSIONS: The Severe Asthma Toolkit is a unique, evidence-based internet resource to support healthcare professionals providing optimal care for people with severe asthma. It is a comprehensive, accessible and independent resource developed by leading severe asthma experts to improve clinician knowledge and skills in severe asthma management.

Lipopolysaccharide induces steroid-resistant exacerbations in a mouse model of allergic airway disease collectively through IL-13 and pulmonary macrophage activation.

BACKGROUND: Acute exacerbations of asthma represent a major burden of disease and are often caused by respiratory infections. Viral infections are recognized as significant triggers of exacerbations; however, less is understood about the how microbial bioproducts such as the endotoxin (lipopolysaccharide (LPS)) trigger episodes. Indeed, increased levels of LPS have been linked to asthma onset, severity and steroid resistance. OBJECTIVE: The goal of this study was to identify mechanisms underlying bacterial-induced exacerbations by employing LPS as a surrogate for infection. METHODS: We developed a mouse model of LPS-induced exacerbation on the background of pre-existing type-2 allergic airway disease (AAD). RESULTS: LPS-induced exacerbation was characterized by steroid-resistant airway hyperresponsiveness (AHR) and an exaggerated inflammatory response distinguished by increased numbers of infiltrating neutrophils/macrophages and elevated production of lung inflammatory cytokines, including TNFα, IFNγ, IL-27 and MCP-1. Expression of the type-2 associated inflammatory factors such as IL-5 and IL-13 were elevated in AAD but not altered by LPS exposure. Furthermore, AHR and airway inflammation were no longer suppressed by corticosteroid (dexamethasone) treatment after LPS exposure. Depletion of pulmonary macrophages by administration of 2-chloroadenosine into the lungs suppressed AHR and reduced IL-13, TNFα and IFNγ expression. Blocking IL-13 function, through either IL-13-deficiency or administration of specific blocking antibodies, also suppressed AHR and airway inflammation. CONCLUSIONS & CLINICAL RELEVANCE: We present evidence that IL-13 and innate immune pathways (in particular pulmonary macrophages) contribute to LPS-induced exacerbation of pre-existing AAD and provide insight into the complex molecular processes potentially underlying microbial-induced exacerbations.

Platelet activating factor receptor regulates colitis-induced pulmonary inflammation through the NLRP3 inflammasome.

Extra-intestinal manifestations (EIM) are common in inflammatory bowel disease (IBD). One such EIM is sub-clinical pulmonary inflammation, which occurs in up to 50% of IBD patients. In animal models of colitis, pulmonary inflammation is driven by neutrophilic infiltrations, primarily in response to the systemic bacteraemia and increased bacterial load in the lungs. Platelet activating factor receptor (PAFR) plays a critical role in regulating pulmonary responses to infection in conditions, such as chronic obstructive pulmonary disease and asthma. We investigated the role of PAFR in pulmonary EIMs of IBD, using dextran sulfate sodium (DSS) and anti-CD40 murine models of colitis. Both models induced neutrophilic inflammation, with increased TNF and IL-1ß levels, bacterial load and PAFR protein expression in mouse lungs. Antagonism of PAFR decreased lung neutrophilia, TNF, and IL-1ß in an NLRP3 inflammasome-dependent manner. Lipopolysaccharide from phosphorylcholine (ChoP)-positive bacteria induced NLRP3 and caspase-1 proteins in human alveolar epithelial cells, however antagonism of PAFR prevented NLRP3 activation by ChoP. Amoxicillin reduced bacterial populations in the lungs and reduced NLRP3 inflammasome protein levels, but did not reduce PAFR. These data suggest a role for PAFR in microbial pattern recognition and NLRP3 inflammasome signaling in the lung.

IL-6 Drives Neutrophil-Mediated Pulmonary Inflammation Associated with Bacteremia in Murine Models of Colitis.

Inflammatory bowel disease (IBD) is associated with several immune-mediated extraintestinal manifestations. More than half of all IBD patients have some form of respiratory pathology, most commonly neutrophil-mediated diseases, such as bronchiectasis and chronic bronchitis. Using murine models of colitis, we aimed to identify the immune mechanisms driving pulmonary manifestations of IBD. We found increased neutrophil numbers in lung tissue associated with the pulmonary vasculature in both trinitrobenzenesulfonic acid- and dextran sulfate sodium-induced models of colitis. Analysis of systemic inflammation identified that neutrophilia was associated with bacteremia and pyrexia in animal models of colitis. We further identified IL-6 as a systemic mediator of neutrophil recruitment from the bone marrow of dextran sulfate sodium animals. Functional inhibition of IL-6 led to reduced systemic and pulmonary neutrophilia, but it did not attenuate established colitis pathology. These data suggest that systemic bacteremia and pyrexia drive IL-6 secretion, which is a critical driver for pulmonary manifestation of IBD. Targeting IL-6 may reduce neutrophil-associated extraintestinal manifestations in IBD patients.