Mast cell activation disrupts interactions between endothelial cells and pericytes during early life allergic asthma.

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.

Advances in the pathogenesis and personalised treatment of paediatric asthma.

The diversity of pathology of severe paediatric asthma demonstrates that the one-size-fits-all approach characterising many guidelines is inappropriate. The term "asthma" is best used to describe a clinical syndrome of wheeze, chest tightness, breathlessness, and sometimes cough, making no assumptions about underlying pathology. Before personalising treatment, it is essential to make the diagnosis correctly and optimise basic management. Clinicians must determine exactly what type of asthma each child has. We are moving from describing symptom patterns in preschool wheeze to describing multiple underlying phenotypes with implications for targeting treatment. Many new treatment options are available for school age asthma, including biological medicines targeting type 2 inflammation, but a paucity of options are available for non-type 2 disease. The traditional reliever treatment, shortacting ß2 agonists, is being replaced by combination inhalers containing inhaled corticosteroids and fast, longacting ß2 agonists to treat the underlying inflammation in even mild asthma and reduce the risk of asthma attacks. However, much decision making is still based on adult data extrapolated to children. Better inclusion of children in future research studies is essential, if children are to benefit from these new advances in asthma treatment.

Pediatric problematic severe asthma: Recent advances in management.

Problematic severe asthma remains a significant challenge to manage, accounting for the majority of healthcare utilization among children with asthma. The heterogeneity is recognized and the clinical phenotypes of "difficult-to-treat" asthma (DA) and "severe therapy-resistant asthma" (STRA) help to guide management. Recent evidence supports molecular distinctions between these phenotypes and shows poor correlations between peripheral and airway markers of inflammation, especially in STRA. Airway neutrophils in the context of childhood severe asthma have been explored, but their role in disease causation, protection, or as bystanders remain unknown, and thus, treatment implications are unclear. Several novel management strategies, including once-daily maintenance therapy, single-device maintenance and reliever therapy, and novel biological treatments are being increasingly used for DA and STRA. However, pediatric data for efficacy of novel treatments is scarce, and when available, is restricted to adolescents. The aim of this review is to highlight recent advances in objective biomarkers that aid stratification and management of childhood severe asthma and to highlight gaps in pediatric evidence. Specifically, the urgent need for efficacy studies to improve the management of problematic severe asthma in children younger than 12 years.

Factors and mechanisms contributing to the development of preschool wheezing disorders.

INTRODUCTION: Half of all children will experience an episode of wheezing by their sixth birthday and acute episodes of wheezing in preschool children account for the majority of all childhood hospital admissions for wheeze. Recurrent preschool wheezing associates with early loss of lung function and a life-long impact on lung health. AREAS COVERED: We reviewed the literature on PubMed from August 2010-2020 focussing on factors associated with wheeze inception and persistence, paying specific attention to mechanistic studies that have investigated the impact of early life exposures in shaping immune responses in children with underlying susceptibility to wheezing. In particular, the role of early allergen sensitization, respiratory infections, and the impact of the environment on shaping the airway microbiome and resulting immune responses are discussed. EXPERT OPINION: There is an abundance of associative data showing the role of in utero and postnatal factors influencing wheeze onset and persistence. However, mechanistic and stratified, biomarker-based interventional studies that confirm these associations are now needed if we are to impact the significant healthcare burden resulting from preschool wheezing disorders.

Diagnosis and Management of Problematic Severe Asthma.

This review will outline an evidence-based approach for diagnosing and managing children with problematic severe asthma (PSA). Children with PSA have uncontrolled asthma symptoms, despite maximal prescribed asthma treatment. These children have high morbidity and mortality and should be referred for specialist respiratory assessment and management. The first step in the assessment of a child with PSA is confirming the diagnosis of asthma using objective evidence. Following this, an assessment of inhaled corticosteroid adherence and a multi-disciplinary team approach is essential for separating difficult asthma (DA) from severe therapy resistant asthma (STRA). The majority of children have DA which entails uncontrolled asthma symptoms due to underlying modifiable factors including poor treatment adherence, poor inhaler technique, exposure to environmental allergens, co-morbid conditions and psycho-social factors. Approximately 20% of children with PSA have STRA, and have persistent asthma symptoms despite good treatment adherence and correction of modifiable factors. Children with STRA typically have multiple and severe aeroallergen sensitization, eosinophilic airway inflammation and high fraction exhaled nitric oxide (FeNO). Further investigation of children with STRA includes an assessment of systemic steroid responsiveness, this is important for confirming the diagnosis of STRA and guiding the choice of additional treatment. Biologics are an add on (immune targeted) therapy for STRA. The current biologics used in children target the T2 helper (Th2) pathway mediating eosinophilic, allergic asthma. CONCLUSION: Future clinical trials of biologics in children will be essential to help identify childhood specific biomarkers and to decide which biologic is best for which individual child.

Integrated Care Models and Child Health: A Meta-analysis.

CONTEXT: Integrated care models may improve health care for children and young people (CYP) with ongoing conditions. OBJECTIVE: To assess the effects of integrated care on child health, health service use, health care quality, school absenteeism, and costs for CYP with ongoing conditions. DATA SOURCES: Medline, Embase, PsycINFO, Cumulative Index to Nursing and Allied Health Literature, and the Cochrane Library databases (1996-2018). STUDY SELECTION: Inclusion criteria consisted of (1) randomized controlled trials, (2) evaluating an integrated care intervention, (3) for CYP (0-18 years) with an ongoing health condition, and (4) including at least 1 health-related outcome. DATA EXTRACTION: Descriptive data were synthesized. Data for quality of life (QoL) and emergency department (ED) visits allowed meta-analyses to explore the effects of integrated care compared to usual care. RESULTS: Twenty-three trials were identified, describing 18 interventions. Compared with usual care, integrated care reported greater cost savings (3/4 studies). Meta-analyses found that integrated care improved QoL over usual care (standard mean difference = 0.24; 95% confidence interval = 0.03-0.44; P = .02), but no significant difference was found between groups for ED visits (odds ratio = 0.88; 95% confidence interval = 0.57-1.37; P = .57). LIMITATIONS: Included studies had variable quality of intervention, trial design, and reporting. Randomized controlled trials only were included, but valuable data from other study designs may exist. CONCLUSIONS: Integrated care for CYP with ongoing conditions may deliver improved QoL and cost savings. The effects of integrated care on outcomes including ED visits is unclear.

Immunotherapy for cervical cancer: Research status and clinical potential.

The high-risk types of human papillomavirus (HPV) have been found to be associated with most cervical cancers and play an essential role in the pathogenesis of the disease. Despite recent advances in preventive HPV vaccine development, such preventive vaccines are unlikely to reduce the prevalence of HPV infections within the next few years, due to their cost and limited availability in developing countries. Furthermore, preventive HPV vaccines may not be capable of treating established HPV infections and HPV-associated lesions, which account for high morbidity and mortality worldwide. Thus, it is important to develop therapeutic HPV vaccines for the control of existing HPV infection and associated malignancies. Therapeutic vaccines are quite different from preventive vaccines in that they require the generation of cell-mediated immunity, particularly T cell-mediated immunity, instead of the generation of neutralizing antibodies. The HPV-encoded early proteins, the E6 and E7 oncoproteins, form ideal targets for therapeutic HPV vaccines, since they are consistently expressed in HPV-associated cervical cancer and its precursor lesions and thus play crucial roles in the generation and maintenance of HPV-associated disease. Our review covers the various therapeutic HPV vaccines for cervical cancer, including live vector-based, peptide or protein-based, nucleic acid-based, and cell-based vaccines targeting the HPV E6 and/or E7 antigens. Furthermore, we review the studies using therapeutic HPV vaccines in combination with other therapeutic modalities and review the latest clinical trials on therapeutic HPV vaccines.