The Allergic Asthma Phenotype

Predicting Prolonged Hospitalization in Asthma Patients: Model Development and External Validation

PURPOSE

This study aims to develop and validate a machine learning model to predict prolonged hospitalization in asthma patients.

PATIENTS AND METHODS

This retrospective cohort study included patients with asthma as the primary diagnosis. We randomly divided 2820 asthma patients from Beth Israel Deaconess Medical Center into a training set and an internal validation set (in an 8:2 ratio), and used 1714 asthma patients from 208 other hospitals in the United States as an external validation cohort. Prolonged hospitalization was the outcome variable. Feature selection was conducted using LASSO regression, univariate logistic regression, and multivariate logistic regression analyses. Nine machine learning algorithms were employed to develop predictive models.

RESULTS

Based on discrimination, calibration, and clinical utility, the Extreme Gradient Boosting (XGBoost) model demonstrated the best overall performance. The nine most important variables in the model were age, oxygen saturation (SpO2), red blood cell count, hemoglobin count, comorbid pneumonia, chronic obstructive pulmonary disease (COPD), congestive heart failure, anxiety, and use of invasive mechanical ventilation. The XGBoost model achieved an area under receiver (AUC) of 0.829 and a Kappa value of 0.439 in the internal validation set, and an AUC of 0.745 and a Kappa value of 0.315 in the external validation set. Decision curve analysis indicated good clinical utility of the model.

CONCLUSION

The XGBoost model can effectively predict prolonged hospitalization in asthma patients.

Correlation between total IgE level and asthma symptom severity in hospitalized children

Background

Status asthmaticus is a common reason for hospitalization and pediatric intensive care unit (PICU) admission among children. While previous studies have demonstrated a correlation between elevated IgE levels and asthma severity in outpatient settings, studies analyzing IgE levels in an inpatient cohort are limited.

Objective

We examined the relationship between baseline IgE levels and symptom severity, maximum respiratory support, and PICU and hospital length of stay in an inpatient pediatric cohort.

Methods

This was a single-center retrospective chart review of children admitted to the Children's Hospital at Montefiore with status asthmaticus as their primary diagnosis. The primary goal was to determine the relationship between baseline IgE levels and severity of illness at time of admission. Secondary outcomes included maximum respiratory support, and PICU and hospital length of stay.

Results

We identified a statistically significant difference (P = .043) in baseline IgE levels between the PICU (median, 608 U/mL) and floor groups (405 IU/mL). There was a positive correlation between IgE level and PICU length of stay (P = .004).

Conclusion

Elevated baseline IgE level is correlated with higher asthma symptom severity when hospitalized and with longer PICU length of stay. Our study adds to the growing body of evidence that those with high baseline IgE levels are at risk of having severe asthma symptomology.

Structural elucidation and anti-asthmatic effects of semi-crystalline polysaccharides from Lignosus rhinocerotis (Cooke) Ryvarden

Asthma is a chronic respiratory disease characterized by airway inflammation. Lignosus rhinocerotis (LR), a medicinal mushroom rich in polysaccharide, has been traditionally used to treat various diseases, including asthma. This study aimed to fractionate, characterize and evaluate the anti-asthmatic effects of polysaccharides from LR (LRP). LRP was isolated and characterized using high-performance liquid chromatography (HPLC), x-ray diffraction analysis (XRD), fourier transform infrared spectrometry (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. In an OVA-induced asthma model, BALB/c mice were sensitized, challenged, and intranasally treated with LRP. Experimental findings demonstrated that LRP exhibits a semi-crystalline nature with predicted structure of → 4)-α-D-Glcp-(1 → and → 3)-β-D-Glcp-(1→. LRP significantly reduced eosinophilia, Th2 cytokines, and IgE levels. Histological analysis revealed LRP's ability to decrease epithelial damage and epithelial and smooth muscle thickness in lung. Reductions in inflammatory cell infiltration, mucus production, and transforming growth factor (TGF)-β1 expression were observed, although not statistically significant. Gene expression analysis indicated that LRP significantly downregulated the inducible nitric oxide synthase (iNOS) expression. This study highlights a detailed structural analysis of LRP and its potential as an alternative for the management of asthma. Further research is needed to elucidate the precise mechanisms of action and optimize its therapeutic application.

Degradation of IL-4Ralpha by Immunoproteasome: implication in airway type 2 inflammation and hyperresponsiveness

Introduction

Immunoproteasome (IP) is induced by pro-inflammatory stimuli such as interferon gamma to regulate inflammation and immunity. Asthma patients with airway type 2 high inflammation (e.g., IL-13) demonstrate more eosinophils and airway hyperresponsiveness (AHR) with less interferon gamma. The role of IP in regulating airway eosinophilic inflammation and AHR has not been investigated.

Methods

This study was aimed to determine how IP regulates type 2 inflammation and AHR using LMP7 (a subunit of IP) deficient mouse lungs, precision-cut lung slices (PCLS), and cultured human airway epithelial cells treated with IL-13 in the absence or presence of an IP inhibitor ONX-0914 or exogenous IP.

Results

LMP7 KO mouse lungs had significantly more IL-4Rα protein expression than the wildtype (WT) mice. Following IL-13 treatment in PCLS, LMP7 KO mice had significantly more airway contraction than WT mice, which was coupled with increased eotaxin-2 levels. IP inhibition by ONX-0914 in IL-13 treated human airway epithelial cells resulted in significantly more IL-4Rα protein expression and eotaxin-3 release. IP inhibition in human PCLS significantly increased AHR.

Conclusion

Collectively, these data demonstrated that IP promotes degradation of IL-4Rα, while inhibits type 2 inflammation and AHR. Enhancement of IP expression or activity may serve as an alternative approach to reduce the severity of type 2 inflammation and AHR.

Low type-2 immune effectors modulate atopic diseases' protective role in pancreatic cancer risk

Studies reported that atopic individuals exhibit a 36% reduced risk of developing pancreatic ductal adenocarcinoma (PDAC); however, the underlying molecular mechanisms remain unclear. This study examines the specific role of type-2 immune response in the atopy-PDAC inverse association. To endotype atopic conditions using type-2 immune effectors (i.e., eosinophils and immunoglobulin-E[IgE]) and investigate their protective effect against PDAC risk, IgE levels were measured in 688 PDAC cases and 558 controls from the PanGenEU case-control study. 'IgE-sensitization' was defined as having >100 kU/L total IgE with lab-tested sensitization to ≥1 food- or aeroallergens. Atopic conditions were determined using the European Community Respiratory Health Survey questionnaire. The UK Biobank cohort's 544 PDAC cases and 92,038 nested controls were categorized based on a threshold of 0.15 × 109 eosinophil cells/L plus self-reported atopy. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated using multivariable logistic regression. Restricted cubic splines were applied to examine the nonlinear relationship between type-2 immune effectors and PDAC risk. PDAC risk was not linearly associated with type-2 immune effectors levels. Compared to low IgE-sensitized non-atopic individuals, the low IgE-sensitized atopic population had significantly reduced PDAC risk (OR = 0.56, 95% CI: 0.35-0.84). Similar trends were observed among atopic individuals with low eosinophil counts (OR = 0.67, 95% CI: 0.47-0.95). Atopic conditions were inversely associated with PDAC risk, particularly among those with low levels of type-2 immune effectors. This indicates the protective effect of atopy against PDAC risk is modulated by low type-2 immune response.

A review in analytical progress for house dust mite allergens

House dust mite (HDM) allergens are one of the most important causes of allergenic diseases in the indoor environment. The World Health Organization (WHO) has defined risk thresholds for Group I HDM allergens as a concentration of 2 and 10 μg/mL in dust for producing asthma risk and polar asthma attacks, respectively. Continuing exposure to high concentrations of HDM allergens greatly increases the risk of developing allergic diseases. Therefore, it's necessary to determine the exposure levels of HDM allergens to estimate the risk. So, various approaches have been developed to directly or indirectly detect HDM allergens in the environment. This paper overviews the developmental progress of HDM allergen detection and introduces the principle of HDM allergen detection methods, including semi-quantitative radioallergosorbent test (RAST), ACAREX test, dot immunobinding assay (DIBA), radioimmunoassay (RIA) which combines the high sensitivity and accuracy, enzyme-linked immunosorbent assay (ELISA) with high accuracy, fluorescent multiple arrays which can simultaneously detect multiple HDM allergens, polymerase chain reaction (PCR), and liquid chromatograph-mass spectrometer (LC-MS) with high sensitivity and accuracy. The paper provides an overall understanding of the development of HDM allergen detection methods and guidance for choosing an appropriate method to detect HDM allergens.

The Late Asthmatic Reaction Is in Part Independent from the Early Asthmatic Reactions

House dust mites (HDM) are the world's most important cause of allergic asthma. It is unclear why some patients with HDM allergy develop an early asthmatic reaction (EAR) only, whereas others react with a dual asthmatic reaction-EAR plus late asthmatic reaction (LAR). In patients with LAR, the symptoms and bronchial inflammation are more severe, and the current knowledge suggests that the EAR always precedes the LAR. The aim of the present study was to investigate whether a LAR can occur separately even without a significant EAR. In a pilot study of 20 patients with asthma and HDM allergy, a bronchial allergen challenge (BAC) was performed on three separate occasions with a tapered allergen dose. Before and 24 h later, exhaled NO (eNO), eosinophils and miRNAs were measured as markers of bronchial inflammation. Compared to BAC1, at BAC2 there was a significant decrease in the EAR from mean 39.25 ± 13.37% to mean 33.55 ± 5.25% (p < 0.01), whereas the LAR remained unchanged: mean 28.10 ± 10.95% to mean 30.31 ± 7.77% (n.s.). At BAC3, both the EAR and the LAR were significantly attenuated compared to the first and second BAC. In 3 (15%) patients, even the tapered allergen dose induced a dual asthmatic reaction. In 10 (50%) patients, the allergen dose was too low to trigger a significant EAR and LAR. In 7 (35%) patients, there was no EAR, but a significant LAR (mean max fall FEV1 20.5 + 4.7%) recorded. Significant correlations (p < 0.05) were found between distinct miRNAs (miR-15a-5p, miR-15b-5p and miR-374a-p5), eNO, and the decline in lung function and the presence of a LAR (p < 0.01). We can demonstrate that a LAR is induced in some patients without an EAR to low allergen exposure. This leads to a strong inflammatory reaction with an increase in eNO and a decrease in FEV1 and distinct miRNAs. Accordingly, these individuals are at greater risk of asthmatic symptoms and remodeling with loss of lung function than patients who do not have a LAR.

Biologic therapies targeting type 2 cytokines are effective at improving asthma symptoms and control-a systematic review and meta-analysis

Background

Allergic asthma is a highly prevalent chronic inflammatory disease driven by aeroallergen exposure. In severe asthma, the current standard of care does not fully control disease symptoms, indicating an unmet clinical need. Biologic therapies targeting cytokines IL-4, IL-5, and IL-13 have been shown to provide benefits to asthmatic patients over currently existing asthma treatments.

Objective

We sought to review the effects of recently developed biologic therapies for asthma treatment.

Methods

In this meta-analysis, the impact of IL-5 and IL-4/IL-13 biologic inhibitors was critically appraised considering overall lung function, symptom control, and oral corticosteroid use in asthmatic patients. Trials were identified using PubMed, Web of Science, Scopus, and clinicaltrials.gov. Clinical trials assessing severe asthmatic participants older than 12 years were included.

Results

The meta-analysis included 6600 participants from 14 trials published in 2013 to 2020. For IL-5 inhibitors, improvements in FEV1 (mean difference [MD], 0.11; 95% CI, 0.11 to 0.12), Asthma Control Questionnaire scores (MD, -0.4; 95% CI, -0.41 to -0.38), annual exacerbation rates (MD, -0.46; 95% CI, -0.48 to -0.45), and oral corticosteroid use (MD, -50; 95% CI, -52.58 to -47.42) favored biologic treatment. Significant improvements in FEV1 (MD, 0.11; 95% CI, 0.10 to 0.11), Asthma Control Questionnaire scores (MD, -0.20; 95% CI, -0.22 to -0.18), and annual exacerbation rates (MD, -0.15; 95% CI, -0.16 to -0.14) were also seen with anti-IL-4/IL-13 biologic therapies. However, anti-IL-4/IL-13 inhibitors were associated with more adverse events than placebo (MD, 1.13; 95% CI, 0.97 to 1.3).

Conclusions

Biologic inhibitors targeting TH2 cytokines are beneficial for improving overall asthma control.

A comparison of the impact of anti-IL5/5r therapies in allergic versus non-allergic patients with severe eosinophilic asthma in a real-life setting

OBJECTIVE

This study aimed to compare the clinical characteristics and treatment outcomes of allergic patients (AP) and non-allergic patients (NAP) with severe eosinophilic asthma (SEA) treated with anti-IL5/IL5R biologic agents (mepolizumab, benralizumab, or reslizumab) over one year. Sub-analyses assessed treatment response variations between AP and NAP based on the biological used and compared outcomes among AP with and without fungal allergy.

METHODS

Observational retrospective analysis. Clinical characteristics, laboratory findings, pulmonary function tests, Asthma Control Test (ACT) scores, oral corticosteroid (OCS) usage, and exacerbation frequency were assessed at the initiation of biological treatment and after one year.

RESULTS

Sixty-five patients with SEA were included, 41 AP and 24 NAP. 55.4% were treated with mepolizumab, 33.8% with benralizumab, and 10.8% with reslizumab. Before anti-IL5/5R treatment, AP had worse baseline outcomes but there were no differences in pulmonary function. Mean annual exacerbation rate and percentage of patients requiring OCS and dose of prednisone were higher in AP than NAP. AP had significantly higher total IgE values. After one year of treatment, more AP discontinued OCS than NAP (p = 0.025). Both experienced a significant reduction in exacerbation frequency (p = 0.001) and improved respiratory function. 70.7% of AP and 60% of NAP improved ACT ≥3 points. There was no significant difference between AP and NAP using mepolizumab (p = 0.145) or benralizumab (p = 0.174) in reducing OCS.

CONCLUSIONS

Anti-IL5/IL5R reduced the need for OCS and improved asthma control, regardless of allergic status. Fungal allergy led to lower ACT scores and higher exacerbations than other allergens; both groups improved with anti-IL5/ILR.

Silencing TRIM8 alleviates allergic asthma and suppressing Th2 differentiation through inhibiting NF-κB/NLRP3 signaling pathway

BACKGROUND AND AIM

Allergic asthma is a primary type of asthma and characterized by T helper 2 (Th2) cells -mediated inflammation. Tripartite motif containing 8 (TRIM8) protein is involved in immunoreaction and inflammatory response in many diseases. However, its role in allergic asthma remains unclear. Medical databank showed that TRIM8 was increased in lung of ovalbumin (OVA)-challenged mice. This study aimed to elucidate the effects of TRIM8 on allergic asthma and Th2 development.

METHODS

Asthma were induced by OVA challenge in mice, and the adenovirus vector loaded with TRIM8 knockdown sequence was delivered into asthma mice by nasal inhalation. The percentage of Th2 cells in lung was assessed by flow cytometric analysis, and the contents of Th2 cytokines (interleukin (IL)-4, IL-5 and IL-13) in bronchoalveolar lavage fluid (BALF) were assessed with ELISA. In vitro Th2 induction was performed in CD4+ cells from mouse spleen, the expression of Th2 molecules (IL-4, IL-5 and GATA binding protein 3 (GATA3)) were measured by real-time PCR. In addition, the nuclear factor-kappa B (NF-κB)/nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3 (NLRP3) signaling was determined.

RESULTS

TRIM8 was highly expressed in the lung tissues of asthmatic mice and Th2-induced CD4+ cells. OVA challenge-induced Th2 development and Th2 cytokine secretion were restrained by silencing of TRIM8 in vivo. Similarly, the Th2 differentiation in vitro was also suppressed by TRIM8 knockdown. TRIM8 inhibited the NF-κB/NLRP3 activity by blocking transforming growth factor-beta-activated kinase 1 (TAK1), and the effects of TRIM8 were abrogated by overexpression of NLRP3.

CONCLUSIONS

Silencing TRIM8 relieved the asthmatic injury in mice and excessive Th2 development via inhibiting the NF-κB/NLRP3 pathway. It is indicated that TRIM8 may contribute to the airway inflammation in allergic asthma via activating the NF-κB/NLRP3 signaling pathway. The current study provided a novel potential target for allergic asthma treatment.

Incorporating Aeroallergen Exposure Metrics into Clinical Asthma Care: A Pilot Study Using A Mixed-Methods Survey to Assess Aeroallergen Knowledge, Perceived Asthma Control, and Mitigation Strategies in Households of Children with Asthma

Objective: Mitigation of household allergens is associated with the reduction of asthma exacerbations in those with allergic asthma and is recommended in recent asthma guidelines. However, we need to better understand patient knowledge of aeroallergens in their homes prior to integrating direct allergen measurement methods into standard asthma care. Methods: We conducted a mixed-methods sequential pilot study consisting of a survey and virtual interview with caregivers of children aged 3 to 15 with asthma diagnosis (any severity) about asthma control, household environment, mitigation knowledge and strategies, and knowledge of allergens and asthma. Results: A total of 21 participants responded and 13 completed the virtual interview. Less than half identified mice (43%), rats (29%), and cockroaches (43%) as sources of allergens on the online survey, and no individuals mentioned these in discussions. Only 23% were able to define the term "allergen," but 69% could list examples. There was a poor correlation between perceived asthma control (57% stated asthma control was good or excellent) compared to asthma that was classified as well controlled per Expert Panel Report 3 (EPR-3) guidelines (33% based on albuterol use and asthma symptoms). Finally, visual identification of mouse infestation was associated with active steps taken to mitigate mouse exposure (P = 0.007). Conclusion: Implementation of new Asthma Management Guidelines: Focused Updates 2020 by the National Institutes of Health will require additional aeroallergen education for individuals with asthma who do not recognize that cockroaches, rats, and mice can cause asthma symptoms, do not know the definition of an allergen, and do not correctly perceive asthma control status. Environmental assessment with education addressing these could hopefully decrease additional pharmaceutical needs.

The volatile oil of Hyssopus cuspidatus Boriss. (HVO) ameliorates OVA-induced allergic asthma via inhibiting PI3K/Akt/JNK/P38 signaling pathway and maintaining airway barrier integrity

ETHNOPHARMACOLOGICAL RELEVANCE

Hyssopus cuspidatus Boriss., a classic Uyghur medicine, is used to treat inflammatory lung diseases such as asthma. But the therapeutic effect and mechanism of the volatile oil of Hyssopus cuspidatus Boriss.(HVO) in asthma therapy remain unclear.

AIM OF THE STUDY

We aim to characterize the constituents of HVO, investigate the therapeutic effect in OVA-induced allergic asthmatic mice and further explore the molecular mechanism.

MATERIALS AND METHODS

In this study, we applied two-dimensional gas chromatography quadrupole time-of-flight mass spectrometry (GC × GC-QTOF MS) to identify the ingredients of HVO. We established OVA-induced asthmatic model to investigate the therapeutic effect of HVO. To further explore the potential molecular pathways, we used network pharmacology approach to perform GO and KEGG pathways enrichment, and then built an ingredient-target-pathway network to identify key molecular pathways. Finally, LPS-induced RAW 264.7 macrophages and OVA-induced asthmatic model were used to validate the potential signaling pathways.

RESULTS

GC × GC-QTOF MS analysis revealed the presence of 123 compounds of HVO. The sesquiterpenes and monoterpenes are the main constituents. The in vivo study indicated that HVO suppressed OVA-induced eosinophilic infiltration in lung tissues, inhibited the elevation of IgE, IL-4, IL-5, and IL-13 levels, downregulated the expressions of phosphorylated PI3K, Akt, JNK and P38, and maintained epithelial barrier integrity via reducing the degradation of occludin, Zo-1, Zo-2, and E-cadherin. The in vitro study also revealed an inhibition of NO release and downregulation of phosphorylated PI3K, Akt, JNK and P38 levels.

CONCLUSION

HVO alleviates airway inflammation in OVA-induced asthmatic mice by inhibiting PI3K/Akt/JNK/P38 signaling pathway and maintaining airway barrier integrity via reducing the degradation of occludin, Zo-1, Zo-2, and E-cadherin.

Choosing the right biologic treatment for individual patients with severe asthma - Lessons learnt from Picasso

Severe asthma represents a true challenge for clinicians from two basic perspectives, i.e.: a rational assessment of the underlying endo/phenotype and the subsequent selection of the best fitted (personalized) and effective treatment. Even though asthma is a heterogeneous disease, in the majority of therapy-compliant patients, it is possible to achieve (almost) complete disease control or even remission through conventional and quite uniform step-based pharmacotherapy, even without phenotyping. However, the absence of deeper assessment of individual patients revealed its handicap to its fullest extent during the first years of the new millennium upon the launch of biological therapeutics for patients with the most severe forms of asthma. The introduction of differentially targeted biologics into clinical practice became a challenge in terms of understanding and recognizing the etiopathogenetic heterogeneity of the asthmatic inflammation, pheno/endotyping, and, consequently, to choose the right biologic for the right patient. The answers to the following three questions should lead to correct identification of the dominant pheno/endotype: Is it really (severe) asthma? Is it eosinophilic asthma? If eosinophilic, is it (predominantly) allergen-driven? The identification of the best achievable and relevant alliance between endotypes and phenotypes ("euphenotypes") should be based not only on the assessment of the actual clinical characteristics and laboratory biomarkers, but more importantly, on the evaluation of their development and changes over time. In the current paper, we present a pragmatic three-step approach to severe asthma diagnosis and management.

Abscisic acid, an evolutionary conserved hormone: Biosynthesis, therapeutic and diagnostic applications in mammals

Abscisic acid (ABA), a phytohormone traditionally recognized for its role in plant stress responses, has recently emerged as a significant player in mammalian defense mechanisms. Like plants, various mammalian cell types synthesize ABA in response to specific health challenges, although the precise pathways remain not fully elucidated. ABA is associated with the regulation of inflammation and insulin signaling, prompting extensive research into its potential as a therapeutic agent for various diseases. ABA exerts its effects through its receptors, particularly PPAR-γ and LANCL-2, which serve as signaling hubs regulating numerous pathways. Through these interactions, ABA profoundly impacts mammalian health, and new ABA targets continue to be identified. Numerous studies in animal models demonstrate ABA's benefit in managing conditions such as neurological and psychiatric disorders, cancer, and malaria infections, all of which involve significant inflammatory dysregulation. In this manuscript we review the studies covering ABA synthesis and release in cell cultures, the signaling pathways regulated by ABA, and how these impact health in preclinical models. Furthermore, we highlight recent research suggesting that measuring ABA levels in human body fluids could serve as a useful biomarker for pathological conditions, providing insights into disease progression and treatment efficacy. This comprehensive review outlines the current understanding of ABA in mammalian pathophysiology, identifying gaps in knowledge, particularly concerning ABA biosynthesis and metabolism in mammals. In addition, this study emphasizes the need for clinical trials to validate the effectiveness of ABA-based therapies and its reliability as a biomarker for various diseases.

Network pharmacology prediction, molecular docking, and molecular dynamics simulation-based strategy to explore the potential mechanism of Huashanshen dripping pill against asthma

OBJECTIVES

Asthma is a heterogeneous disease characterized by chronic airway inflammation. Huashanshen dripping pills (HSS) are commonly utilized for relieving asthma, relieving cough, and expelling phlegm. At present, the molecular mechanism against airway inflammation remains unclear.

METHODS

In this study, network pharmacology, molecular docking technology, and molecular dynamic simulation were used to predict the therapeutic pathways of HSS for asthma. The ovalbumin-induced mouse model was used to further validate the prediction by RT-qPCR, western blot, immunofluorescence, and related methods.

KEY FINDINGS

The findings indicate that HSS improves lung function and relieves lung inflammation by reducing inflammatory cell infiltration around the bronchus and reducing eosinophilic counts in bronchoalveolar lavage fluid (BALF). In addition, it lowers the levels of inflammatory cytokines and the expression levels of interleukin-4, interleukin-5, and interleukin-13 mRNA. HSS also inhibits the phosphorylation and nuclear translocation of NF-κB p65 protein.

CONCLUSIONS

All results suggested that HSS can decrease airway inflammation in asthmatic mice by inhibiting NF-κB signaling pathway. This finding will shed light on how it can be used to treat asthma.

Ameliorative Effects of Ginger on Allergic Diseases: An Updated Review

The hypersensitivity reaction of the immune system to harmless environmental substances causes allergic diseases. Today, about 22%-30% of the world's population suffers from allergic diseases. Since the probability of change in the genetic structure during the past decades of lives is very low, genetic disorders cannot be blamed for causing allergic diseases. Thus, factors such as air pollution, climate change, change in diet, increased antibiotics consumption, change in the gut microbiome, migration toward urban areas, and increase in airborne allergens should be considered as the main causes of the spread and increase in allergic diseases. Methods of preventing contact with allergens, drug treatment, and allergen-specific immunotherapy are used to treat allergic diseases. In recent years, the therapeutic efficacy of herbal compounds has been significantly investigated by the scientific community, because these compounds have very few side effects. Ginger is one of the plant compounds that have anti-inflammatory, antioxidant, and immunomodulatory properties. The ameliorative effects of this plant on allergic diseases have been identified. Therefore, the aim of this short review is to summarize the knowledge, which is available about the ameliorative properties of the compounds found in the ginger plant that can reduce the clinical symptoms of allergic diseases.

Benralizumab for allergic asthma: a randomised, double-blind, placebo-controlled trial

BACKGROUND

Benralizumab induces rapid and near-complete depletion of eosinophils from blood and lung tissue. We investigated whether benralizumab could attenuate the allergen-induced late asthmatic response (LAR) in participants with allergic asthma.

METHODS

Participants with allergic asthma who demonstrated increased sputum eosinophils and LAR at screening were randomised to benralizumab 30 mg or matched placebo given every 4 weeks for 8 weeks (3 doses). Allergen challenges were performed at weeks 9 and 12 when blood, sputum, bone marrow and bronchial tissue eosinophils and LAR were assessed.

RESULTS

46 participants (mean age 30.9 years) were randomised to benralizumab (n=23) or placebo (n=23). Eosinophils were significantly reduced in the benralizumab group compared with placebo in blood at 4 weeks and sputum and bone marrow at 9 weeks after treatment initiation. At 7 h after an allergen challenge at week 9, sputum eosinophilia was significantly attenuated in the benralizumab group compared to placebo (least squares mean difference -5.81%, 95% CI -10.69- -0.94%; p=0.021); however, the LAR was not significantly different (least squares mean difference 2.54%, 95% CI 3.05-8.12%; p=0.363). Adverse events were reported for seven (30.4%) and 14 (60.9%) participants in the benralizumab and placebo groups, respectively.

CONCLUSION

Benralizumab administration over 8 weeks resulted in a significant attenuation of blood, bone marrow and sputum eosinophilia in participants with mild allergic asthma; however, there was no change in the LAR, suggesting that eosinophils alone are not a key component of allergen-induced bronchoconstriction.

Specific microRNA Profile Associated with Inflammation and Lipid Metabolism for Stratifying Allergic Asthma Severity

The mechanisms underlying severe allergic asthma are complex and unknown, meaning it is a challenge to provide the most appropriate treatment. This study aimed to identify novel biomarkers for stratifying allergic asthmatic patients according to severity, and to uncover the biological mechanisms that lead to the development of the severe uncontrolled phenotype. By using miRNA PCR panels, we analyzed the expression of 752 miRNAs in serum samples from control subjects (n = 15) and mild (n = 11) and severe uncontrolled (n = 10) allergic asthmatic patients. We identified 40 differentially expressed miRNAs between severe uncontrolled and mild allergic asthmatic patients. Functional enrichment analysis revealed signatures related to inflammation, angiogenesis, lipid metabolism and mRNA regulation. A random forest classifier trained with DE miRNAs achieved a high accuracy of 97% for severe uncontrolled patient stratification. Validation of the identified biomarkers was performed on a subset of allergic asthmatic patients from the CAMP cohort at Brigham and Women's Hospital, Harvard Medical School. Four of these miRNAs (hsa-miR-99b-5p, hsa-miR-451a, hsa-miR-326 and hsa-miR-505-3p) were validated, pointing towards their potential as biomarkers for stratifying allergic asthmatic patients by severity and providing insights into severe uncontrolled asthma molecular pathways.

The Effect of a TLR3 Agonist on Airway Allergic Inflammation and Viral Infection in Immunoproteasome-Deficient Mice

Allergic asthma is characterized by increased type 2 inflammation, including eosinophils. Subjects with allergic asthma have recurrent symptoms due to their constant exposure to environmental allergens, such as house dust mite (HDM), which can be further exacerbated by respiratory infections like rhinovirus. The immunoproteasome (IP) is a proteolytic machinery that is induced by inflammatory mediators during virus infection, but the role of the IP in airway allergic inflammation during rhinovirus infection remains unknown. Wild-type (WT) and IP knockout (KO) mice were challenged with HDM. At 48 h after the last HDM challenge, mice were infected with rhinovirus 1B (RV-A1B) for 24 h. After HDM and RV-A1B treatment, IP KO (vs. WT) mice had significantly more lung eosinophils and neutrophils, as well as a significantly higher viral load, but less IFN-beta expression, compared to WT mice. A TLR3 agonist polyinosinic-polycytidylic acid (Poly I:C) treatment after RV-A1B infection in HDM-challenged IP KO mice significantly increased IFN-beta expression and reduced viral load, with a minimal effect on the number of inflammatory cells. Our data suggest that immunoproteasome is an important mechanism functioning to prevent excessive inflammation and viral infection in allergen-exposed mice, and that Poly I:C could be therapeutically effective in enhancing the antiviral response and lessening the viral burden in lungs with IP deficiency.

Outdoor aeroallergen impacts on asthma exacerbation among sensitized and nonsensitized Philadelphia children

Background

Outdoor aeroallergens, such as pollens and molds, are known triggers of asthma exacerbation; however, few studies have examined children's aeroallergen response based on sensitization.

Objective

Our aim was to compare the relative impact of aeroallergen levels on asthma exacerbation between pediatric patients with asthma who tested positive or negative for sensitization to particular allergens.

Methods

A case-crossover design study was conducted to examine associations between outdoor aeroallergen levels and asthma exacerbation events among children living in Philadelphia, Pennsylvania, who were treated within a large pediatric care network. Sensitization to common allergens was characterized in a subset of patients with asthma exacerbation who had undergone skin prick testing (5.5%). Odds ratios (ORs) and 95% CIs were estimated in all patients with asthma exacerbation and in those sensitized or not sensitized to aeroallergens.

Results

Children who were sensitized to a particular allergen had higher odds of asthma exacerbation with exposure to the allergen (ie, early-season tree pollen, oak tree pollen, early-season weed pollen, and late-season molds) than did all patients with asthma or nonsensitized patients. For example, the association between early-season tree pollen and asthma exacerbation among sensitized children (>90th percentile vs ≤25th, OR = 2.28 [95% CI = 1.23-4.22]) was considerably stronger than that estimated among all patients (OR = 1.34 [95% CI = 1.19-1.50]), and it was also substantially different from the lack of association seen among nonsensitized children (OR = 0.89 [95% CI = 0.51-1.55] [P value for heterogeneity = .03]).

Conclusion

More prevalent allergy testing may be useful for prevention of asthma exacerbation by informing interventions targeted to sensitized children and tailored for particular aeroallergens.

The role of IL-2 cytokine family in asthma

BACKGROUND

The interleukin-2 (IL-2) family of cytokines, including IL-2, IL-4, IL-7, IL-9, IL-15, and IL-21, are pivotal regulators of the immune response, impacting both innate and adaptive immunity. Understanding their molecular characteristics, receptor interactions, and signalling pathways is essential for elucidating their roles in health and disease.

OBJECTIVES

This review provides a comprehensive overview of the IL-2 family of cytokines, highlighting their molecular biology, receptor interactions, and signalling mechanisms. Furthermore, it explores the involvement of IL-2 family cytokines in the pathogenesis of chronic respiratory diseases, with a specific focus on chronic obstructive pulmonary disease (COPD) and asthma.

METHODS

A thorough literature review was conducted to gather insights into the molecular biology, receptor interactions, and signalling pathways of IL-2 family cytokines. Additionally, studies investigating the roles of these cytokines in chronic respiratory diseases, particularly COPD and asthma, were analysed to discern their implications in wider pathophysiology of disease.

RESULTS

IL-2 family cytokines exert pleiotropic effects on immune cells, modulating cellular proliferation, differentiation, and survival. Dysregulation of IL-2 family cytokines has been implicated in the pathogenesis of chronic respiratory illnesses, including COPD and asthma. Elevated levels of IL-2 and IL-9 have been associated with disease severity in COPD, while IL-4 and IL-9 play crucial roles in asthma pathogenesis by promoting airway inflammation and remodelling.

CONCLUSION

Understanding the intricate roles of IL-2 family cytokines in chronic respiratory diseases provides valuable insights into potential therapeutic targets for these conditions. Targeting specific cytokines or their receptors may offer novel treatment modalities to attenuate disease progression and improve clinical outcomes in patients with COPD and asthma.

Efficacy and safety of benralizumab in elderly patients with severe eosinophilic asthma

Background

Biologics are the important drugs for severe asthma, but clinical trials included few elderly patients. Data on the safety and efficacy of benralizumab in elderly asthma patients are limited.

Methods

This clinical study was a multicentre, retrospective, observational study at two hospitals. Patients aged ≥18 years diagnosed with severe asthma treated with benralizumab were included. Elderly patients were defined as those aged 70 years or older. Efficacy and safety were then analyzed in elderly and non-elderly patients. The primary endpoints were the annual number of asthma exacerbations for efficacy and the discontinuation rate due to adverse events for safety.

Results

Between August 2016 and October 2022, 61 patients were enrolled; 10 patients were excluded, and 51 (22 elderly, 29 non-elderly) patients were analyzed. In elderly patients, the annual number of asthma exacerbations before treatment with benralizumab (pre-benralizumab) was 3.78, and the number during treatment with benralizumab was 1.26, a decrease of 2.52 (95% confidence interval [CI], 1.3 to 3.74, p < 0.001). In non-elderly patients, the annual number of asthma exacerbation in the pre-benralizumab period was 3.24, and during treatment with benralizumab it was 0.68, a decrease of 2.56 (95% CI, 1.3 to 3.82, p < 0.001). There was no significant difference in discontinuation due to treatment-related adverse events (elderly vs non-elderly, 2 (9%) vs 0 (0%), p = 0.18).

Conclusion

Benralizumab reduced the annual number of asthma exacerbations and was well tolerated in elderly patients.

High humidity and NO2 co-exposure exacerbates allergic asthma by increasing oxidative stress, inflammatory and TRP protein expressions in lung tissue

Allergic asthma is a chronic inflammatory airway disease with a high mortality rate and a rapidly increasing prevalence in recent decades that is closely linked to environmental change. Previous research found that high humidity (HH) and the traffic-related air pollutant NO2 both aggregated allergic asthma. Their combined effect and mechanisms on asthma exacerbation, however, are unknown. Our study aims to toxicologically clarify the role of HH (90%) and NO2 (5 ppm) on allergic asthma. Ninety male Balb/c mice were randomly assigned to one of six groups (n = 15 in each): saline control, ovalbumin (OVA)-sensitized, OVA + HH, OVA + NO2, OVA + HH + NO2, and OVA + HH + NO2+Capsazepine (CZP). After 38 days of treatment, the airway function, pathological changes in lung tissue, blood inflammatory cells, and oxidative stress and inflammatory biomarkers were comprehensively assessed. Co-exposure to HH and NO2 exacerbated histopathological changes and airway hyperresponsiveness, increased IgE, oxidative stress markers malonaldehyde (MDA) and allergic asthma-related inflammation markers (IL-1β, TNF-α and IL-17), and upregulated the expressions of the transient receptor potential (TRP) ion channels (TRPA1, TRPV1 and TRPV4). Our findings show that co-exposure to HH and NO2 disrupted the Th1/Th2 immune balance, promoting allergic airway inflammation and asthma susceptibility, and increasing TRPV1 expression, whereas CZP reduced TRPV1 expression and alleviated allergic asthma symptoms. Thus, therapeutic treatments that target the TRPV1 ion channel have the potential to effectively manage allergic asthma.

Novel Insights into Changes in Gene Expression within the Hypothalamus in Two Asthma Mouse Models: A Transcriptomic Lung-Brain Axis Study

Patients with asthma experience elevated rates of mental illness. However, the molecular links underlying such lung-brain crosstalk remain ambiguous. Hypothalamic dysfunction is observed in many psychiatric disorders, particularly those with an inflammatory component due to many hypothalamic regions being unprotected by the blood-brain barrier. To gain a better insight into such neuropsychiatric sequelae, this study investigated gene expression differences in the hypothalamus following lung inflammation (asthma) induction in mice, using RNA transcriptome profiling. BALB/c mice were challenged with either bacterial lipopolysaccharide (LPS, E. coli) or ovalbumin (OVA) allergens or saline control (n = 7 per group), and lung inflammation was confirmed via histological examination of postmortem lung tissue. The majority of the hypothalamus was micro-dissected, and total RNA was extracted for sequencing. Differential expression analysis identified 31 statistically significant single genes (false discovery rate FDR5%) altered in expression following LPS exposure compared to controls; however, none were significantly changed following OVA treatment, suggesting a milder hypothalamic response. When gene sets were examined, 48 were upregulated and 8 were downregulated in both asthma groups relative to controls. REACTOME enrichment analysis suggests these gene sets are involved in signal transduction metabolism, immune response and neuroplasticity. Interestingly, we identified five altered gene sets directly associated with neurotransmitter signaling. Intriguingly, many of these altered gene sets can influence mental health and or/neuroinflammation in humans. These findings help characterize the links between asthma-induced lung inflammation and the brain and may assist in identifying relevant pathways and therapeutic targets for future intervention.

ADRB2 and ADCY9 Sequence Variations in Brazilian Asthmatic Patients

Asthma is a chronic inflammatory respiratory condition, characterized by variable airflow limitation, leading to clinical symptoms such as dyspnea and chest tightness. These symptoms result from an underlying inflammatory process. The β2 agonists are bronchodilators prescribed for the relief of the disease. Nevertheless, their efficacy exhibits substantial interindividual variability. Currently, there is widespread recognition of the association between specific genetic variants, predominantly located within the ADRB2 and ADCY9 genes and their efficacy. This association, usually represented by the presence of non-synonymous single nucleotide polymorphisms (SNPs) have a strong impact in the protein functionality. The prevalence of these mutations varies based on the ethnic composition of the population and thus understanding the profiles of variability in different populations would contribute significantly to standardizing the use of these medications. In this study, we conducted a sequence-based genotyping of the relevant SNPs within the ADRB2 and ADCY9 genes in patients undergoing treatment with bronchodilators and/or corticosteroids at two healthcare facilities in the state of Rio de Janeiro, Brazil. We investigated the presence of c.46A>G, c.79C>G, c.252G>A, and c.491C>T SNPs within the ADRB2, and c.1320018 A>G within the ADCY9. Our results were in line with existing literature data with both for individuals in Brazil and Latin American.

S100A8/9 modulates perturbation and glycolysis of macrophages in allergic asthma mice

Background

Allergic asthma is the most prevalent asthma phenotype and is associated with the disorders of immune cells and glycolysis. Macrophages are the most common type of immune cells in the lungs. Calprotectin (S100A8 and S100A9) are two pro-inflammatory molecules that target the Toll-like receptor 4 (TLR4) and are substantially increased in the serum of patients with severe asthma. This study aimed to determine the effects of S100A8/A9 on macrophage polarization and glycolysis associated with allergic asthma.

Methods

To better understand the roles of S100A8 and S100A9 in the pathogenesis of allergic asthma, we used ovalbumin (OVA)-induced MH-S cells, and OVA-sensitized and challenged mouse models (wild-type male BALB/c mice). Enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, flow cytometry, hematoxylin-eosin staining, and western blotting were performed. The glycolysis inhibitor 3-bromopyruvate (3-BP) was used to observe changes in glycolysis in mice.

Results

We found knockdown of S100A8 or S100A9 in OVA-induced MH-S cells inhibited inflammatory cytokines, macrophage polarization biomarker expression, and pyroptosis cell proportion, but increased anti-inflammatory cytokine interleukin (IL)-10 mRNA; also, glycolysis was inhibited, as evidenced by decreased lactate and key enzyme expression; especially, knockdown of S100A8 or S100A9 inhibited the activity of TLR4/myeloid differentiation primary response gene 88 (MyD88)/Nuclear factor kappa-B (NF-κB) signaling pathway. Intervention with lipopolysaccharides (LPS) abolished the beneficial effects of S100A8 and S100A9 knockdown. The observation of OVA-sensitized and challenged mice showed that S100A8 or S100A9 knockdown promoted respiratory function, improved lung injury, and inhibited inflammation; knockdown of S100A8 or S100A9 also suppressed macrophage polarization, glycolysis levels, and activation of the TLR4/MyD88/NF-κB signaling pathway in the lung. Conversely, S100A9 overexpression exacerbated lung injury and inflammation, promoting macrophage polarization and glycolysis, which were antagonized by the glycolysis inhibitor 3-BP.

Conclusion

S100A8 and S100A9 play critical roles in allergic asthma pathogenesis by promoting macrophage perturbation and glycolysis through the TLR4/MyD88/NF-κB signaling pathway. Inhibition of S100A8 and S100A9 may be a potential therapeutic strategy for allergic asthma.

Macrophage polarization: an important role in inflammatory diseases

Macrophages are crucial cells in the human body's innate immunity and are engaged in a variety of non-inflammatory reactions. Macrophages can develop into two kinds when stimulated by distinct internal environments: pro-inflammatory M1-like macrophages and anti-inflammatory M2-type macrophages. During inflammation, the two kinds of macrophages are activated alternatively, and maintaining a reasonably steady ratio is critical for maintaining homeostasis in vivo. M1 macrophages can induce inflammation, but M2 macrophages suppress it. The imbalance between the two kinds of macrophages will have a significant impact on the illness process. As a result, there are an increasing number of research being conducted on relieving or curing illnesses by altering the amount of macrophages. This review summarizes the role of macrophage polarization in various inflammatory diseases, including autoimmune diseases (RA, EAE, MS, AIH, IBD, CD), allergic diseases (allergic rhinitis, allergic dermatitis, allergic asthma), atherosclerosis, obesity and type 2 diabetes, metabolic homeostasis, and the compounds or drugs that have been discovered or applied to the treatment of these diseases by targeting macrophage polarization.

Treatable Traits in Asthma: The Importance of Extrapulmonary Traits-GERD, CRSwNP, Atopic Dermatitis, and Depression/Anxiety

Treatable traits is a personalized medicine approach to the management of airway disease. Assessing traits within the 3 domains of pulmonary, extrapulmonary, and behavioral/lifestyle/risk factor traits, and applying targeted treatments to effectively manage these traits, enables a holistic and personalized approach to care. Asthma is a heterogeneous and complex airway disease that is frequently complicated by several extrapulmonary traits that impact asthma outcomes and predict future outcomes. We propose that the identification of extrapulmonary and behavioral risk factor traits and the implementation of targeted therapy will lead to improved management of people with asthma. Furthermore, many extrapulmonary traits present as "connected comorbidities"; that is, they coexist with asthma, have an impact on asthma, and effective treatment improves both asthma and the comorbidity or the comorbidities may share a similar mechanism. In this review, we explore this concept and look at atopic dermatitis, chronic rhinosinusitis with nasal polyps, gastroesophageal reflux disease, anxiety, and depression as treatable traits of asthma and how these can be managed using this approach.

Studying of anti-inflammatory and antioxidant effects of tectorigenin in ovalbumin-induced asthma mice models

BACKGROUND

Allergic asthma is an important respiratory system problem characterized by airway inflammation, breathlessness, and bronchoconstriction. Allergic asthma and its outcomes are triggered by type 2 allergic immune responses. Tectorigenin is a methoxy-isoflavone with anti-inflammatory effects. In this study, we investigated the effects of tectorigenin on the pathophysiology of allergic asthma in an animal model.

METHODS

Asthmatic mice were treated with tectorigenin. Then airway hyperresponsiveness (AHR), eosinophil percentage, levels of interleukin (IL)-33, IL-25, IL-13, IL-5, IL-4, total and ovalbumin (OVA)-specific immunoglobulin (Ig)E, and lung histopathology were evaluated.

RESULT

Tectorigenin significantly (P 〈 0.05) reduced eosinophil infiltration (41 ± 7%) in the broncho-alveolar lavage fluid (BALF), serum IL-5 level (41 ± 5, pg/mL), and bronchial and vascular inflammation (scores of 1.3 ± 0.2 and 1.1 ± 0.3, respectively) but had no significant effects on AHR, serum levels of IL-33, -25, -13, and -4 (403 ± 24, 56 ± 7, 154 ± 11, and 89 ± 6 pg/mL, respectively), total and OVA-specific IgE (2684 ± 265 and 264 ± 19 ng/mL, respectively), goblet cell hyperplasia, and mucus production.

CONCLUSION

Tectorigenin could control inflammation and the secretion of inflammatory mediators of asthma, so it can be regarded as a potential antiasthma treatment with the ability to control eosinophilia-related problems.

Demethylzeylasteral (T-96) Alleviates Allergic Asthma via Inhibiting MAPK/ERK and NF-κB Pathway

INTRODUCTION

Demethylzeylasteral (T-96), a new extract of Tripterygium wilfordii Hook F, exerted immunomodulatory properties in autoimmune diseases, but its effect on airway inflammatory diseases remains unclear. Our study aims to explore the protective effect and underlying mechanism of T-96 in allergic asthma.

METHODS

The OVA-induced asthmatic mice were administered by gavage with T-96 (0.1 mg/10 g, 0.3 mg/10 g, or 0.6 mg/10 g) 1 h before each challenge. The airway hyperresponsiveness was assessed, pathological changes were evaluated by HE and PAS staining, and expressions of Th2 cytokines were determined by PCR and ELISA. The activation of MAPK/ERK and NF-κB pathway was assessed by western blot.

RESULTS

T-96 significantly relieved airway hyperresponsiveness in asthmatic mice, evidenced by reduced airway resistance (Raw) and increased lung compliance dynamic compliance (Cdyn). Also, enhanced inflammatory infiltration and mucus hypersecretion were ameliorated in lungs of asthmatic mice following increasing doses of T-96 treatment, accompanied by decreased eosinophils in bronchoalveolar lavage fluid (BALF), IgE and OVA-specific IgE levels in serum, and downregulated IL-5 and IL-13 expressions in BALF and lung tissues as well. Notably, phosphorylation levels of p38 MAPK, ERK, and p65 NF-κB were obviously increased in asthmatic mice compared with the control group, which were then abrogated upon T-96 treatment.

CONCLUSION

This study first revealed that T-96 alleviated allergic airway inflammation and airway hyperresponsiveness via inhibiting MAPK/ERK and NF-κB pathway. Thus, T-96 could potentially act as a new anti-inflammatory agent in allergic asthma.

Female-specific enhancement of eosinophil recruitment and activation in a type 2 innate inflammation model in the lung

A sex disparity in asthma prevalence and severity exists in humans. Multiple studies have highlighted the role of innate cells in shaping the adaptive immune system in chronic asthma. To explore the sex bias in the eosinophilic response, we delivered IL-33 to the lungs of mice and delineated the kinetics by which the inflammatory response was induced. Our data demonstrate that females recruited more eosinophils capable of responding to IL-33. Eosinophil activation occurred selectively in the lung tissue and was enhanced in females at all time points. This increase was associated with increased ex vivo type 2 cytokine and chemokine production and female-specific expansion of group 2 innate lymphoid cells lacking expression of the killer-cell lectin-like receptor G1. Our findings suggest that the enhanced eosinophilic response in females is due, firstly, to a greater proportion of eosinophils recruited to the lungs in females that can respond to IL-33; and secondly, to an enhanced production of type 2 cytokines in females. Our data provide insight into the mechanisms that guide the female-specific enhancement of eosinophil activation in the mouse and form the basis to characterize these responses in human asthmatics.

Sphingosine kinase 1-specific inhibitor PF543 reduces goblet cell metaplasia of bronchial epithelium in an acute asthma model

Sphingosine kinase 1 (SPHK1) has been shown to play a key role in the pathogenesis of asthma where SPHK1-generated sphingosine-1-phosphate (S1P) is known to mediate innate and adaptive immunity while promoting mast cell degranulation. Goblet cell metaplasia (GCM) contributes to airway obstruction in asthma and has been demonstrated in animal models. We investigated the role of PF543, a SPHK1-specific inhibitor, in preventing the pathogenesis of GCM using a murine (C57BL/6) model of allergen-induced acute asthma. Treatment with PF543 before triple allergen exposure (DRA: House dust mite, Ragweed pollen, and Aspergillus) reduced inflammation, eosinophilic response, and GCM followed by reduced airway hyperreactivity to intravenous methacholine. Furthermore, DRA exposure was associated with increased expression of SPHK1 in the airway epithelium which was reduced by PF543. DRA-induced reduction of acetylated α-tubulin in airway epithelium was associated with an increased expression of NOTCH2 and SPDEF which was prevented by PF543. In vitro studies using human primary airway epithelial cells showed that inhibition of SPHK1 using PF543 prevented an allergen-induced increase of both NOTCH2 and SPDEF. siRNA silencing of SPHK1 prevented the allergen-induced increase of both NOTCH2 and SPDEF. NOTCH2 silencing was associated with a reduction of SPDEF but not that of SPHK1 upon allergen exposure. Our studies demonstrate that inhibition of SPHK1 protected allergen-challenged airways by preventing GCM and airway hyperreactivity, associated with downregulation of the NOTCH2-SPDEF signaling pathway. This suggests a potential novel link between SPHK1, GCM, and airway remodeling in asthma.NEW & NOTEWORTHY The role of SPHK1-specific inhibitor, PF543, in preventing goblet cell metaplasia (GCM) and airway hyperreactivity (AHR) is established in an allergen-induced mouse model. This protection was associated with the downregulation of NOTCH2-SPDEF signaling pathway, suggesting a novel link between SPHK1, GCM, and AHR.

Examining allergy related diseases in Africa: A scoping review protocol

During recent decades, allergy related diseases have emerged as a growing area of concern in developing regions of the world, including Africa. Worldwide prevalence of allergic diseases has grown to an estimated 262 million for asthma, 400 million for allergic rhinitis (or hay fever), 171 million with atopic dermatitis (or eczema), and over 200 million for food allergy. In Africa, considerable variability exists in the data surrounding prevalence at the continent-wide, regional, and study site levels. Furthermore, research conducted in many rural areas and underdeveloped countries in Africa remains limited, and presently, little has been done to characterize and map the extremely heterogeneous body of literature which confounds research efforts. This scoping review will seek to identify studies examining the prevalence, management strategies, outcomes, and associated risk factors for allergy related diseases in Africa. The Joanna Briggs Institute's scoping review methods will be followed, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Review (PRISMA-ScR) was used for writing the protocol. Four databases (Embase, Global Health, PubMed, African Journals Online) will be searched for literature published from 2003 to 2023 in any language. Title and abstract screening and full-text screening will be completed by two independent reviewers using Covidence; conflicts resolved by a third reviewer. Data will be extracted using Covidence by two reviewers independently. To report the results, we will follow the PRISMA-ScR checklist and report descriptive statistics and a narrative summary.

A cross talk between microbial metabolites and host immunity: Its relevance for allergic diseases

BACKGROUND

Allergic diseases, including respiratory and food allergies, as well as allergic skin conditions have surged in prevalence in recent decades. In allergic diseases, the gut microbiome is dysbiotic, with reduced diversity of beneficial bacteria and increased abundance of potential pathogens. Research findings suggest that the microbiome, which is highly influenced by environmental and dietary factors, plays a central role in the development, progression, and severity of allergic diseases. The microbiome generates metabolites, which can regulate many of the host's cellular metabolic processes and host immune responses.

AIMS AND METHODS

Our goal is to provide a narrative and comprehensive literature review of the mechanisms through which microbial metabolites regulate host immune function and immune metabolism both in homeostasis and in the context of allergic diseases.

RESULTS AND DISCUSSION

We describe key microbial metabolites such as short-chain fatty acids, amino acids, bile acids and polyamines, elucidating their mechanisms of action, cellular targets and their roles in regulating metabolism within innate and adaptive immune cells. Furthermore, we characterize the role of bacterial metabolites in the pathogenesis of allergic diseases including allergic asthma, atopic dermatitis and food allergy.

CONCLUSION

Future research efforts should focus on investigating the physiological functions of microbiota-derived metabolites to help develop new diagnostic and therapeutic interventions for allergic diseases.

MicroRNA Profiling of the Inflammatory Response after Early and Late Asthmatic Reaction

A high proportion of house dust mite (HDM)-allergic asthmatics suffer from both an early asthmatic reaction (EAR) and a late asthmatic reaction (LAR) which follows it. In these patients, allergic inflammation is more relevant. MiRNAs have been shown to play an important role in the regulation of asthma's pathology. The aim of this study was to analyze the miRNA profile in patients with mild asthma and an HDM allergy after bronchial allergen provocation (BAP). Seventeen patients with EAR/no LAR and 17 patients with EAR plus LAR, determined by a significant fall in FEV1 after BAP, were differentially analyzed. As expected, patients with EAR plus LAR showed a more pronounced allergic inflammation and FEV1 delta drop after 24 h. NGS-miRNA analysis identified the down-regulation of miR-15a-5p, miR-15b-5p, and miR-374a-5p after BAP with the highest significance in patients with EAR plus LAR, which were negatively correlated with eNO and the maximum decrease in FEV1. These miRNAs have shared targets like CCND1, VEGFA, and GSK3B, which are known to be involved in airway remodeling, basement membrane thickening, and Extracellular Matrix deposition. NGS-profiling identified miRNAs involved in the inflammatory response after BAP with HDM extract, which might be useful to predict a LAR.

The pharmacotherapeutic management of allergic rhinitis in people with asthma

INTRODUCTION

Up to 90% of asthmatic patients have comorbid allergic rhinitis (AR). Although appropriate therapy of AR can improve asthma symptoms and management, AR is often underdiagnosed and under-treated in asthmatics.A non-systematic literature research was conducted on AR as a comorbidity and risk factor of asthma. Latest international publications in medical databases, international guidelines, and the Internet were reviewed.

AREAS COVERED

Based on the conducted literature research there is proved evidence of the necessity of diagnosis and treatment of AR in patients with asthma because it affects health care utilization. Therefore, it is recommended in national and global guidelines.

EXPERT OPINION

AR increases the risk of asthma development and contributes to the severity of an existing asthma. Early treatment of AR with drugs as intranasal steroids, antihistamines, leukotriene receptor antagonists, and especially allergen-specific immunotherapy can reduce the risk of asthma development and the concomitant medication use in addition to severity of symptoms in AR and asthma.

Fungal diversity in homes and asthma morbidity among school-age children in New York City

BACKGROUND

Asthma development has been inversely associated with exposure to fungal diversity. However, the influence of fungi on measures of asthma morbidity is not well understood.

OBJECTIVES

This study aimed to test the hypothesis that fungal diversity is inversely associated with neighborhood asthma prevalence and identify specific fungal species associated with asthma morbidity.

METHODS

Children aged 7-8 years (n = 347) living in higher (11-18%) and lower (3-9%) asthma prevalence neighborhoods were recruited within an asthma case-control study. Fungal communities were analyzed from floor dust using high-throughput DNA sequencing. A subset of asthmatic children (n = 140) was followed to age 10-11 to determine asthma persistence.

RESULTS

Neighborhood asthma prevalence was inversely associated with fungal species richness (P = 0.010) and Shannon diversity (P = 0.059). Associations between neighborhood asthma prevalence and diversity indices were driven by differences in building type and presence of bedroom carpet. Among children with asthma at age 7-8 years, Shannon fungal diversity was inversely associated with frequent asthma symptoms at that age (OR 0.57, P = 0.025) and with asthma persistence to age 10-11 (OR 0.48, P = 0.043). Analyses of individual fungal species did not show significant associations with asthma outcomes when adjusted for false discovery rates.

DISCUSSION

Lower fungal diversity was associated with asthma symptoms in this urban setting. Individual fungal species associated with asthma morbidity were not detected. Further research is warranted into building type, carpeting, and other environmental characteristics which influence fungal exposures in homes.

Outdoor Alternaria and Cladosporium spores and acute asthma

BACKGROUND

Outdoor Alternaria and Cladosporium spores are ubiquitous. Few studies have assessed their impact on asthma hospitalizations providing conflicting results, mainly focused on vulnerable paediatric populations. We aimed to study the impact of outdoor Alternaria and Cladosporium concentrations on acute hospitalizations in the Capital Region of Denmark.

METHODS

This is a bi-directional case-crossover study with 26 years of national registry data at individual level on acute asthma hospitalizations and daily average data on Alternaria and Cladosporium, pollen (Artemisia, Poaceae), maximal temperature, and air pollution. Conditional logistic regression models were applied to assess the associations. Concentration quartiles at lag 0 were used for categorizing the exposure.

RESULTS

For lags 0-2, the odds of hospitalization were significantly higher for both Alternaria and Cladosporium at concentration quartile 2-4 compared with quartile 1. When stratified for age and sex, odds of hospitalization at Alternaria quartiles 2-4 were significantly higher in males below 40 years at lag 0-2, and at lag 0 in females (18-30 years), while quartiles 2-4 of Cladosporium concentrations were associated with significantly higher odds in boys (0-17 years) at lag 1-3, males (18-39 years) at lag 0-1, females (18-39 years) at lag 1-2, males (40-64 years) at lag 0-2, females (40-64 years) at lag 0 and 2, in seniors (65+ years) male at lag 1-2 and female at lag 0-1. The effect of Alternaria varied significantly depending on the level of Cladosporium (p < .0001).

CONCLUSION

Ambient Alternaria and Cladosporium spores can induce asthma hospitalizations. Males are more susceptible to both genera. Males and females under age 40 years are more susceptible to Alternaria.

Characteristics of Allergic, Eosinophilic, and Overlapping Asthma Phenotypes Among Pediatric Patients with Current Asthma: A Cross-Sectional Study from Saudi Arabia

Purpose

Asthma is one of the most common chronic diseases affecting 10%-30% of children in Saudi Arabia. Although data exist on adult asthma phenotyping and endotyping in Saudi Arabia, little is known about asthma phenotypes in Saudi children.

Patients and Methods

This cross-sectional study enrolled pediatric patients diagnosed with bronchial asthma and followed in the pediatric pulmonology clinic of the Abha Maternity and Children Hospital between August 2021 and May 2023.

Results

A total of 321 children (aged 5-14 years) were analyzed. The population was classified into allergic [169 (52.6%)], eosinophilic [144 (44.9%)], and overlapping allergic and eosinophilic asthma [97 (30.2%)] phenotypes. Regarding asthma severity, 35.5%, 50.2%, and 14.3% were classified as mild, moderate, and severe, respectively. Of the 321 patients in the study, 124 (38.6%) had at least one asthma exacerbation that required hospitalization. The number of reported missed school days in the previous year was 1571 days [190 (59.2%) patients reported at least one missed school day]. The factors associated with the likelihood of uncontrolled asthma for all study participants included: emergency room (ER) visit last year (OR = 3.7, 95% CI:0.6-15.9]), overlapping eosinophilic and allergic (OR = 3.2, 95% CI = 1.8-5.9), and allergic phenotype (OR = 2.7, 95% CI = 1.3-5.4). The level of asthma control differed significantly among the three asthma phenotypes (p = 0.037).

Conclusion

Allergic asthma is the most prevalent asthma phenotype in this study, followed by the eosinophilic phenotype. The research has also shown that several factors predict uncontrolled asthma, including a family history of asthma, previous admission to the PICU, and previous hospitalization ever. There is, therefore, a definite need for multicenter cohort studies to better understand the phenotypes and endotypes of childhood asthma, as it could offer therapeutic and prognostic relevance.

Interleukin-4 (C590T) Gene Polymorphism in Association with Asthma Severity

Background

A significant link between T allele of the IL-4 (C590T) gene and developing asthma in some populations was reported. However, no study discussed the link between IL-4 (C590T) gene polymorphism and asthma severity groups (mild and severe). This study investigated the link between IL-4 gene variation and asthma severity.

Methods

The study included 215 asthmatic patients, of which 102 had mild asthma, and 126 participants were healthy controls. A previously published polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used to identify various IL-4 (C590T) gene polymorphism genotypes.

Results

The T allele frequency was higher in mild asthma (p=0.002) but not in severe asthma (p=0.12) compared to controls. In mild asthma, the CT genotype and (CT+TT versus CC) increased the likelihood of asthma threefold (p<0.001, 0.001). However, no significant association with severe asthma was found in either genetic model. Stratification analysis showed that the C allele and CC genotype increased the risk of severe asthma (p=0.01). The recessive genetic model indicated a decrease in the risk of severe asthma (OR=0.5, p=0.01) in the non-adjusted regression analysis. Adjusting for age, sex, and other risk factors revealed that the IL-4 gene polymorphism did not influence the risk of severe asthma (OR=0.92, p=0.80); however, being an elderly female with a history of childhood-onset disease and associated nasal polyp (NP) increased the likelihood of severe asthma, OR=1.08, 2.01, 2.36, 8.42; p<0.001, 0.05, 0.05, <0.001, respectively.

Conclusion

The T allele and CT genotype in the co-dominant genetic model and the (CT+TT) genotype in the recessive model were found to have a higher likelihood of developing mild asthma but not severe asthma; severe asthma was found to be higher in elderly females with a history of childhood-onset disease and associated nasal polyps.

Promising treatment biomarkers in asthma

Asthma is a highly heterogenous disease which researchers over time have attempted to classify into different phenotypes and endotypes to improve diagnosis, prognosis and treatment. Earlier classifications based on reaction to environmental allergens, age, sex and lung function have evolved, and today, the use of precision medicine guided by biomarkers offers new perspectives on asthma management. Identifying biomarkers that may reveal the underlying pathophysiology of the disease will help to select the patients who will benefit most from specific treatments. This review explores the classification of asthma phenotypes and focuses on the most recent advances in using biomarkers to guide treatment.

Efficacy of Biologics in Patients with Allergic Severe Asthma, Overall and by Blood Eosinophil Count: A Literature Review

Patients with uncontrolled, allergic severe asthma may be prescribed biologic therapies to reduce exacerbations and improve disease control. Randomized controlled trials (RCTs) of these therapies have differed in design, with varying results overall and by baseline blood eosinophil count (BEC). This study describes published annualized asthma exacerbation rate (AAER) reductions from RCTs in patients with allergic severe asthma, overall and by baseline BEC category. A literature search was performed to identify published phase 3 RCT data of US Food and Drug Administration-approved biologics for severe asthma in patients with severe, uncontrolled asthma and confirmed sensitization to perennial aeroallergens. Analyses focused on AAER reduction versus placebo in the overall population and/or in those with an elevated or low BEC at baseline or screening. Baseline serum total immunoglobulin E levels varied between RCT populations. In patients with allergic severe asthma across all BEC categories, data were available for tezepelumab, dupilumab, benralizumab and omalizumab only; the greatest AAER reduction was observed with tezepelumab. In patients with allergic severe asthma and BECs of ≥ 260 cells/µL or ≥ 300 cells/μL, AAER reductions were observed with all biologics (tezepelumab, dupilumab, mepolizumab, benralizumab and omalizumab); the greatest AAER reduction was observed with tezepelumab and the smallest AAER reduction was observed with omalizumab. In patients with allergic severe asthma and BECs of < 260 cells/µL or < 300 cells/μL (regardless of historical BEC), an AAER reduction was observed with tezepelumab but not with benralizumab or omalizumab. Differential mechanisms of action may explain the differences in results observed between biologics. Among patients with allergic severe asthma, the efficacy of biologics in RCTs varied considerably overall and by BEC. Tezepelumab was the only biologic to demonstrate AAER reductions consistently across all subgroups. These differences can inform provider treatment decisions when selecting biologic treatments for patients with allergic severe asthma.

MRGPRX2, drug pseudoallergies, inflammatory diseases, mechanisms and distinguishing MRGPRX2- and IgE/FcεRI-mediated events

MRGPRX2, a novel Gaq -coupled human mast cell receptor, mediates non-immune adverse reactions without the involvement of antibody priming. Constitutively expressed by human skin mast cells, MRGPRX2 modulates cell degranulation producing pseudoallergies manifesting as itch, inflammation and pain. The term pseudoallergy is defined in relation to adverse drug reactions in general and immune/non-immune-mediated reactions in particular. A list of drugs with MRGPRX2 activity is presented, including a detailed examination of three important and widely used approved therapies: neuromuscular blockers, quinolones and opioids. For the clinician, the significance of MRGPRX2 is considered as an aid in distinguishing and ultimately identifying specific immune and non-immune inflammatory reactions. Anaphylactoid/anaphylactic reactions, neurogenic inflammation and inflammatory diseases with a clear or strongly suspected association with MRGPRX2 activation are examined. Inflammatory diseases include chronic urticaria, rosacea, atopic dermatitis, allergic contact dermatitis, mastocytosis, allergic asthma, ulcerative colitis and rheumatoid arthritis. MRGPRX2- and allergic IgE/FcεRI-mediated reactions may be clinically similar. Importantly, the usual testing procedures do not distinguish the two mechanisms. Currently, identification of MRGPRX2 activation and diagnosis of pseudoallergic reactions is generally viewed as a process of exclusion once other non-immune and immune processes, particularly IgE/FcεRI-mediated degranulation of mast cells, are ruled out. This does not take into account that MRGPRX2 signals via β-arrestin, which can be utilized to detect MRGPRX2 activation by employing MRGPRX2 transfected cells to assess MRGPRX2 activation via two pathways, the G-protein-independent β-arrestin pathway and the G-protein-dependent Ca2+ pathway. Testing procedures, interpretations for distinguishing mechanisms, patient diagnosis, agonist identification and drug safety evaluations are addressed.

Causal relationship between Butyricimonas and allergic asthma: a two-sample Mendelian randomization study

Background

Growing evidence has well documented the close association between the gut microbiome and allergic respiratory disease, which has been notably represented by allergic asthma. However, it is unclear whether this association is a causal link. Therefore, we investigated the potential causal associations between the gut microbiome and allergic asthma or other allergic diseases.

Methods

In this study, we performed two-sample Mendelian randomization (MR) analyses by using the publicly available genome-wide association study (GWAS) summary data. Single-nucleotide polymorphisms (SNPs) that significantly correlated were selected as instrumental variables. The inverse variance weighted (IVW) method was used to examine the potential causal gut microbial genera for allergic asthma and other allergic diseases. The robustness of the primary findings of the MR analyses was ensured by using different sensitivity analyses.

Results

Combining the findings from multiple analyses, the host genetic-driven increases in Butyricimonas at the genus level were positively correlated with the risk of allergic asthma. In addition, phylum Bacteroidetes and class Bacteroidia were also found to have negative associations with the risk of allergic asthma; genus Slackia was identified as having potential causal effects with allergic asthma. No clear evidence of pleiotropy and heterogeneity was observed in genus Butyricimonas. Butyricimonas was also found to have an association with allergic rhinitis, but not with other allergic diseases.

Conclusion

Our findings indicate that there are new gut microbial genera that were causally associated with the risk of allergic asthma and other allergic diseases, and offer novel insights into the pathogenesis of allergic respiratory diseases.

Asthma prevalence based on the Baidu index and China's Health Statistical Yearbook from 2011 to 2020 in China

Background

Due to environmental pollution, changes in lifestyle, and advancements in diagnostic technology, the prevalence of asthma has been increasing over the years. Although China has made early efforts in asthma epidemiology and prevention, there is still a lack of unified and comprehensive epidemiological research within the country. The objective of the study is to determine the nationwide prevalence distribution of asthma using the Baidu Index and China's Health Statistical Yearbook.

Methods

Based on China's Health Statistical Yearbook, we analyzed the gender and age distribution of asthma in China from 2011 to 2020, as well as the length of hospitalization and associated costs. By utilizing the Baidu Index and setting the covering all 31 provinces and autonomous regions in China, we obtained the Baidu Index for the keyword 'asthma'. Heatmaps and growth ratios described the prevalence and growth of asthma in mainland China.

Results

The average expenditure for discharged asthma (standard deviation) patients was ¥5,870 (808). The average length of stay (standard deviation) was 7.9 (0.38) days. During the period of 2011 to 2020, hospitalization expenses for asthma increased while the length of hospital stay decreased. The proportion of discharged patients who were children under the age of 5 were 25.3% (2011), 19.4% (2012), 16% (2013), 17.9% (2014), 13.9% (2015), 11.3% (2016), 10.2% (2017), 9.4% (2018), 8.1% (2019), and 7.2% (2020), respectively. The prevalence of asthma among boys was higher than girls before the age of 14. In contrast, the proportion of women with asthma was larger than men after the age of 14. During the period from 2011 to 2020, the median [The first quartile (Q1)-the third quartile (Q3)] daily asthma Baidu index in Guangdong, Beijing, Jiangsu, Sichuan, and Zhejiang were 419 (279-476), 328 (258-376), 315 (227-365), 272 (166-313), and 312 (233-362) respectively. Coastal regions showed higher levels of attention toward asthma, indicating a higher incidence rate. Since 2014, there has been a rapid increase in the level of attention toward asthma, with the provinces of Qinghai, Sichuan, and Guangdong experiencing the fastest growth.

Conclusion

There are regional variations in the prevalence of asthma among different provinces in China, and the overall prevalence of asthma is increasing.

Invariant natural killer T cells in lung diseases

Invariant natural killer T (iNKT) cells are a subset of T cells that are characterized by a restricted T-cell receptor (TCR) repertoire and a unique ability to recognize glycolipid antigens. These cells are found in all tissues, and evidence to date suggests that they play many immunological roles in both homeostasis and inflammatory conditions. The latter include lung inflammatory diseases such as asthma and infections: the roles of lung-resident iNKT cells in these diseases have been extensively researched. Here, we provide insights into the biology of iNKT cells in health and disease, with a particular focus on the role of pulmonary iNKT cells in airway inflammation and other lung diseases.

Establishing a Virtual Home Assessment Program: from Concept to Implementation as a Result of the COVID-19 Pandemic

PURPOSE OF REVIEW

Environmental home assessments have traditionally been performed in-person at the homes of Children's Mercy Kansas City patients. The COVID-19 pandemic brought many challenges to the way patients interact with their healthcare providers, including home visiting programs. Reaching out to patients with high-risk asthma and immunocompromised health was still needed, despite the pandemic. This project's purpose was to develop a virtual (telemedicine) healthy home assessment protocol that would continue to meet patients' needs during the isolation resulting from the pandemic.

RECENT FINDINGS

This is a newly developing approach to performing home environmental assessments with limited published research. Research on the effective use of telemedicine as an alternative to in-person clinic visits has shown that for some health conditions telemedicine represents a useful technique to engage with patients and caregivers. For some conditions, like pediatric asthma, it provides a similar level of efficacy in disease management while providing a more efficient form of interaction. This article describes the development and delivery process, timelines of caregiver interaction, and guidelines for performing virtual home assessments. It summarizes the challenges and benefits of using a virtual process for delivering home assessment services for asthma and allergy patients. Overall, caregivers indicated they found the use of virtual technology had significant benefits for them including their personal comfort and the time efficiency gained by using virtual visits to interact with Healthy Homes Program staff.

Childhood asthma phenotypes and endotypes: a glance into the mosaic

BACKGROUND

Asthma is an inflammatory lung disease that constitutes the most common noncommunicable chronic disease in childhood. Childhood asthma shows large heterogeneity regarding onset of disease, symptoms, severity, prognosis, and response to therapy.

MAIN BODY

Evidence suggests that this variability is due to distinct pathophysiological mechanisms, which has led to an exhaustive research effort to understand and characterize these distinct entities currently designated as "endotypes." Initially, studies focused on identifying specific groups using clinical variables yielding different "clinical phenotypes." In addition, the identification of specific patterns based on inflammatory cell counts and cytokine data has resulted in "inflammatory endotypes." More recently, an increasing number of molecular data from high-throughput technology ("omics" data) have allowed to investigate more complex "molecular endotypes."

CONCLUSION

A better definition and comprehension of childhood asthma heterogeneity is key for improving diagnosis and treatment. This review aims at summarizing the current knowledge on this topic and discusses some limitations in their application as well as recommendations for future studies.

Reliability of Total Serum IgE Levels to Define Type 2 High and Low Asthma Phenotypes

Background: High total IgE levels are weak predictors of T2High and have been reported in nonallergic asthma. Therefore, the role of total serum IgE (IgE) in the T2High phenotype is still debated. Objective: This study investigated the reliability of stratifying asthmatics into IgEHigh and IgELow within the T2High and T2Low phenotypes. Methods: This cross-sectional single-center study investigated the association of clinical, functional, and bio-humoral parameters in a large asthmatic population stratified by IgE ≥ 100 kU/L, allergen sensitization, B-EOS ≥ 300/µL, and FENO ≥ 30 ppb. Results: Combining T2 biomarkers and IgE identifies (1) T2Low-IgELow (15.5%); (2) T2Low-IgEHigh (5.1%); (3) T2High-IgELow (33.6%); and T2High-IgEHigh (45.7%). T2Low-IgELow patients have more frequent cardiovascular and metabolic comorbidities, a higher prevalence of emphysema, and higher LAMA use than the two T2High subgroups. Higher exacerbation rates, rhinitis, and anxiety/depression syndrome characterize the T2Low-IgEHigh phenotype vs. the T2Low-IgELow phenotype. Within the T2High, low IgE was associated with female sex, obesity, and anxiety/depression. Conclusions: High IgE in T2Low patients is associated with a peculiar clinical phenotype, similar to T2High in terms of disease severity and nasal comorbidities, while retaining the T2Low features. IgE may represent an additional biomarker for clustering asthma in both T2High and T2Low phenotypes rather than a predictor of T2High asthma "per se".

Changes in asthma emergency department visits in the United States during the COVID-19 pandemic

OBJECTIVE

A better understanding of the impacts of the Coronavirus disease 2019 (COVID-19) pandemic on emergency department (ED) visits for asthma is needed to improve asthma control.

METHODS

Using data from the National Syndromic Surveillance Program (NSSP), we assessed changes in average weekly asthma ED visits in the United States in 3 surveillance periods: 1) March 15, 2020-January 2, 2021; 2) January 3, 2021-January 1, 2022; and 3) January 2-March 5, 2022, relative to pre-pandemic comparison periods between December 30, 2018 and December 28, 2019. For each surveillance period, we assessed changes in asthma ED visits by age group and sex.

RESULTS

For the surveillance period beginning March 15, 2020, average weekly asthma ED visits declined 31% relative to what was observed during the comparison period - that is, from 45,276 visits/week in 2019 to 31,374 visits/week in 2020. Declines of over 19% and 26% were observed for 2021 and 2022, respectively, relative to the comparison periods. In all surveillance periods, the largest declines occurred among children, especially those ages 0-4 (74%) and 5-11 (66%) years.

CONCLUSIONS

The COVID-19 pandemic impacted asthma ED visits in the United States. The impact was greater among children than adults, as ED visits among children were notably lower during all three pandemic surveillance periods than during the corresponding pre-pandemic periods. Additional information about the roles of behaviors of patients with asthma and changes in asthma care might improve our understanding of the reasons underlying these observed changes.