Search

Allergic asthma generally starts during early life and is linked to substantial tissue remodeling and lung dysfunction. Although angiogenesis is a feature of the disrupted airway, the impact of allergic asthma on the pulmonary microcirculation during early life is unknown. Here, using quantitative imaging in precision-cut lung slices (PCLSs), we report that exposure of neonatal mice to house dust mite (HDM) extract disrupts endothelial cell/pericyte interactions in adventitial areas. Central to the blood vessel structure, the loss of pericyte coverage was driven by mast cell (MC) proteases, such as tryptase, that can induce pericyte retraction and loss of the critical adhesion molecule N-cadherin. Furthermore, spatial transcriptomics of pediatric asthmatic endobronchial biopsies suggests intense vascular stress and remodeling linked with increased expression of MC activation pathways in regions enriched in blood vessels. These data provide previously unappreciated insights into the pathophysiology of allergic asthma with potential long-term vascular defects., Introduction Allergic asthma commonly develops during early childhood. While it is difficult to precisely define the prevalence of children affected, it is now estimated that between 5% and 20% of [...]

Asthma affects approximately 300 million individuals worldwide and the onset predominantly arises in childhood. Children are exposed to multiple environmental irritants, such as viruses and allergens, that are common triggers for asthma onset, whilst their immune systems are developing in early life. Understanding the impact of allergen exposures on the developing immune system and resulting alterations in lung function in early life will help prevent the onset and progression of allergic asthma in children. In this study, we developed an in silico model describing the pulmonary immune response to a common allergen, house dust mite, to investigate its downstream impact on the pathophysiology of asthma, including airway eosinophilic inflammation, remodelling, and lung function. We hypothesised that altered epithelial function following allergen exposure determines the onset of airway remodelling and abnormal lung function, which are irreversible with current asthma therapies. We calibrated the in silico model using age appropriate in vivo data from neonatal and adult mice. We validated the in silico model using in vivo data from mice on the effects of current treatment strategies. The in silico model recapitulates experimental observations and provides an interpretable in silico tool to assess airway pathology and the underlying immune responses upon allergen exposure. The in silico model simulations predict the extent of bronchial epithelial barrier damage observed when allergen sensitisation occurs and demonstrate that epithelial barrier damage and impaired immune maturation are critical determinants of reduced lung function and asthma development. The in silico model demonstrates that both epithelial barrier repair and immune maturation are potential targets for therapeutic intervention to achieve successful asthma prevention. [ABSTRACT FROM AUTHOR]

Immunity in early life encompasses the delicate interphase at the maternal-fetal stage, as well as rapid development and adaptation that occur as the newborn transitions from the protected maternal environment to functioning in the outside world. Understanding the forces that shape immunity in the very young and that lay the groundwork for an effective adult immune system holds both questions and promise.

Asthma is a descriptive label for an obstructive inflammatory disease in the lower airways manifesting with symptoms including breathlessness, cough, difficulty in breathing, and wheezing. From a clinician's point of view, asthma symptoms can commence at any age, although most patients with asthma—regardless of their age of onset—seem to have had some form of airway problems during childhood. Asthma inception and related pathophysiologic processes are therefore very likely to occur early in life, further evidenced by recent lung physiologic and mechanistic research. Herein, we present state-of-the-art updates on the role of genetics and epigenetics, early viral and bacterial infections, immune response, and pathophysiology, as well as lifestyle and environmental exposures, in asthma across the life course. We conclude that early environmental insults in genetically vulnerable individuals inducing abnormal, pre-asthmatic airway responses are key events in asthma inception, and we highlight disease heterogeneity across ages and the potential shortsightedness of treating all patients with asthma using the same treatments. Although there are no interventions that, at present, can modify long-term outcomes, a precision-medicine approach should be implemented to optimize treatment and tailor follow-up for all patients with asthma. [ABSTRACT FROM AUTHOR]

Introduction: Healthcare requires new technologies to deliver hybrid services. Before embedding health-delivery transformations including physiotherapy in asthma clinics, it is essential to give young people and their carers a voice to facilitate co-designing of services. Objective: To co-design hybrid telehealth physiotherapy services and online resources for, and in partnership with, young people with asthma and dysfunctional breathing, and their families. Methods: Experience based co-design study undertaken at a specialist paediatric difficult asthma clinic, including online service user focus groups and electronic questionnaires for service providers. Eight children aged between 11 and 17 years and their families and 11 members of the multi-disciplinary team (MDT) managing children with difficult asthma were recruited purposively. Results: A series of seven online videos were created, topics included: how to support a breathless child, education on how we breathe, breathing patterns, symptom differentiation, breathlessness, rescue breathing techniques, and exercise. Each video has downloadable resources. Five children and four parents wrote blogs to share their experiences. A live online 12-week physiotherapy program was developed on a web-based platform called Asthma Kids. Conclusion: Co-design enabled partnership working to develop hybrid telehealth physiotherapy services and prototype interventions to support home practice for children with asthma and dysfunctional breathing. CONTRIBUTIONS OF PAPER: Service provider and service user insight into experiences of using digital healthcare technologies. Novel co-designed physiotherapy-based 12-week program of interventions for children and young people with asthma and dysfunctional breathing. Novel co-designed online resources to support physiotherapy home practice for children and young people with asthma and dysfunctional breathing. [ABSTRACT FROM AUTHOR]

Recurrent wheezing in preschool children is heterogeneous and results from numerous genetic and environmental risk factors, which result in the same final clinical manifestation of acute episodes of wheezing but have distinct underlying mechanisms. Effective disease‐modifying approaches, therefore, need to target the pathways driving the symptoms. We have good evidence to show that targeting airway eosinophilia alone in early‐life preschool wheezing and using inhaled corticosteroids is not disease‐modifying. Although airway remodelling develops early in preschool wheezing, the challenge is identifying suitable treatments for structural airway changes. There is increasing evidence for the role of lower airway bacterial infection contributing to wheeze episodes, but clinical trials investigating the impact of targeted antibiotic treatment on disease modification are needed. There is also increasing data supporting an association between lower airway neutrophilia and wheezing in a subgroup of preschool children, but direct causation and the role of neutrophil function remain unknown. Finally, there is encouraging preliminary data for the role of inactivated mixed bacterial lysates in children with non‐allergic, infection‐associated wheeze episodes, but the impact on longer‐term outcomes and their mechanism of action is unknown. This review outlines a range of potential novel targets and approaches that may enable secondary prevention of asthma from preschool wheezing. In parallel, the potential for harm when interventions are introduced indiscriminately is highlighted. Some of the challenges that need to be addressed, including trial designs allowing tailored interventions, the need for non‐invasive biomarkers for targeted interventions, and ensuring extended and long‐term follow‐up after intervention, are highlighted. [ABSTRACT FROM AUTHOR]

Background: Preschool wheeze attacks triggered by recurrent viral infections, including respiratory syncytial virus (RSV), are associated with an increased risk of childhood asthma. However, mechanisms that lead to asthma following early‐life viral wheezing remain uncertain. Methods: To investigate a causal relationship between early‐life RSV infections and onset of type 2 immunity, we developed a neonatal murine model of recurrent RSV infection, in vivo and in silico, and evaluated the dynamical changes of altered airway barrier function and downstream immune responses, including eosinophilia, mucus secretion and type 2 immunity. Results: RSV infection of neonatal BALB/c mice at 5 and 15 days of age induced robust airway eosinophilia, increased pulmonary CD4+IL‐13+ and CD4+IL‐5+ cells, elevated levels of IL‐13 and IL‐5 and increased airway mucus at 20 days of age. Increased bronchoalveolar lavage albumin levels, suggesting epithelial barrier damage, were present and persisted following the second RSV infection. Computational in silico simulations demonstrated that recurrent RSV infection resulted in severe damage of the airway barrier (epithelium), triggering the onset of type 2 immunity. The in silico results also demonstrated that recurrent infection is not always necessary for the development of type 2 immunity, which could also be triggered with single infection of high viral load or when the epithelial barrier repair is compromised. Conclusions: The neonatal murine model demonstrated that recurrent RSV infection in early life alters airway barrier function and promotes type 2 immunity. A causal relationship between airway barrier function and type 2 immunity was suggested using in silico model simulations. [ABSTRACT FROM AUTHOR]