Upper airway and skin symptoms in allergic and non-allergic asthma: Results from the Swedish GA2LEN study

Evaluation of the reproducibility of responses to nasal allergen challenge and effects of inhaled nasal corticosteroids

BACKGROUND

Similar immune responses in the nasal and bronchial mucosa implies that nasal allergen challenge (NAC) is a suitable early phase experimental model for drug development targeting allergic rhinitis (AR) and asthma. We assessed NAC reproducibility and the effects of intranasal corticosteroids (INCS) on symptoms, physiology, and inflammatory mediators.

METHODS

20 participants with mild atopic asthma and AR underwent three single blinded nasal challenges each separated by three weeks (NCT03431961). Cohort A (n = 10) underwent a control saline challenge, followed by two allergen challenges. Cohort B (n = 10) underwent a NAC with no treatment intervention, followed by NAC with 14 days pre-treatment with saline nasal spray (placebo), then NAC with 14 days pre-treatment with INCS (220 μg triamcinolone acetonide twice daily). Nasosorption, nasal lavage, blood samples, forced expiratory volume 1 (FEV1), total nasal symptom score (TNSS), peak nasal inspiratory flow (PNIF) were collected up to 24 h after NAC. Total and active tryptase were measured as early-phase allergy biomarkers (≤30 min) and IL-13 and eosinophil cell counts as late-phase allergy biomarkers (3-7 h) in serum and nasal samples. Period-period reproducibility was assessed by intraclass correlation coefficients (ICC), and sample size estimates were performed using effect sizes measured after INCS.

RESULTS

NAC significantly induced acute increases in nasosorption tryptase and TNSS and reduced PNIF, and induced late increases in nasosorption IL-13 with sustained reductions in PNIF. Reproducibility across NACs varied for symptoms and biomarkers, with total tryptase 5 min post NAC having the highest reproducibility (ICC = 0.91). Treatment with INCS inhibited NAC-induced IL-13 while blunting changes in TNSS and PNIF. For a similar crossover study, 7 participants per treatment arm are needed to detect treatment effects comparable to INCS for TNSS.

CONCLUSION

NAC-induced biomarkers and symptoms are reproducible and responsive to INCS. NAC is suitable for assessing pharmacodynamic activity and proof of mechanism for drugs targeting allergic inflammation.

Allergic sensitisation and type-2 inflammation is associated with new-onset and persistent allergic disease

BACKGROUND

Allergic disease is common. The aim of this study was to look at the change in asthma and rhinitis over time and to characterise factors contributing to remission and persistence of disease.

METHODS

This cohort study included 255 individuals with or without asthma and or rhinitis that participated in a population survey and a follow-up 10 years later. The participants were tested for allergic sensitisation, total IgE, multiplex allergen component analysis and type-2 inflammatory markers: exhaled nitric oxide (FE NO), eosinophil cationic protein (ECP) and eosinophil-derived neurotoxin (EDN).

RESULTS

Of the 132 healthy individuals, 112 remained healthy, 16 developed rhinitis, 4 asthma and rhinitis over the 10 years. Out of 82 subjects with rhinitis, 26 went into remission, 53 remained unchanged and 3 developed asthma in addition to rhinitis. None of the 41 participants with asthma and rhinitis went into remission. Subjects with persistent rhinitis and asthma had higher levels of total IgE (odds ratio [OR] 95% confidence interval [CI]: 6.16 [3.05-12.5]) at baseline and after 10 years, and FE NO and ECP at baseline (OR per log unit increase, 95% CI 5.21 [1.20-22.7] and 6.32 [1.52-26.4], respectively), compared with those that remained healthy. Subjects with persistent rhinitis were more likely to be sensitised to grass pollen and had higher total IgE levels than those that went into remission. Individuals with persistent asthma were more likely to be sensitised to tree pollen and furry animals than those with only persistent rhinitis (OR 95% CI: 3.50 [1.29-9.49] and 6.73 [2.00-22.6], respectively).

CONCLUSION

IgE sensitisation and total IgE levels are associated with the persistence of rhinitis and asthma. Participants with persistent allergic disease had higher levels of allergen sensitisation and type 2 inflammation markers at baseline than those who remained healthy.

The NLRP3 inflammasome as a new target in respiratory disorders treatment

In recent years a continuous increase in new cases of respiratory disorders, such as rhinitis, asthma, and chronic obstructive pulmonary disease (COPD), has been observed. The exact pathomechanism of these diseases is still blurry, resulting in the lack of targeted and effective therapy. The conventional use of treatment strategies, such as antihistamine drugs and/or glucocorticosteroids act mainly symptomatically and have significant side effects. Specific allergen immunotherapy is only useful in the management of specific allergies and selected patients. Therefore, new therapeutic solutions are constantly being sought. The novelty of recent years has been the association between NLRP3 inflammasome activation and the development of airway inflammatory diseases. This seems to be an interesting therapeutic target that may support or even replace traditional therapies in the future. The review presented, discusses the contribution of NLRP3 inflammasome to the development of allergic rhinitis, allergic asthma, and COPD. Moreover, the modulatory properties of probiotics as potential inhibitors of NLRP3 inflammasome are emphasised.

Multimorbidity in asthma, association with allergy, inflammatory markers and symptom burden, results from the Swedish GA2 LEN study

Background

Asthma is common worldwide and a large part of subjects with asthma have concomitant allergic multimorbidity in the form of rhinitis and/or eczema.

Objective

The aim of this study is to investigate whether the presence of allergic multimorbidity in asthma relates to allergic sensitization, allergic and respiratory symptoms, quality of life, inflammatory markers, lung function, use of medication and background factors.

Methods

A total of 437 asthmatics from the (GA²LEN) cross‐sectional survey in Sweden were grouped depending on the presence of rhinitis and/or eczema. The impact of allergic multimorbidity was assessed in terms of allergic sensitization, allergic and respiratory symptoms, quality of life, type‐2 inflammatory markers (exhaled nitric oxide, eosinophil activation markers, periostin), lung function, use of medication and background factors.

Results

Subjects with asthma, rhinitis and eczema were more likely to be sensitized to seasonal allergens (67% vs 32%, P < .001), food allergens (54% vs 18%, P < .001) and to have a higher degree of sensitization than subjects with only asthma (23% vs 10%, P < .001). Subjects with allergic multimorbidity more often had allergic reactions to food (28% vs 10%, P = .002), more respiratory symptoms and anxiety/depression (40% vs, 14%, P < .001) than subjects with only asthma, despite having similar levels of type 2 inflammatory markers. Individuals with allergic multimorbidity were more likely to be diagnosed with asthma before the age of 12 (48% vs 27%, P = .016) and to have maternal heredity for allergy (53% vs 33%, P = .011) than subjects with only asthma.

Conclusion and clinical relevance

Asthmatics with allergic multimorbidity are more likely to be sensitized to seasonal aeroallergens, food allergens and they have a higher degree of sensitization compared with those with only asthma. Allergic multimorbidity is associated with respiratory and allergy symptoms, anxiety and/or depression.

Study of atopic multimorbidity in subjects with rhinitis using multiplex allergen component analysis

BACKGROUND

Rhinitis is a common problem within the population. Many subjects with rhinitis also have atopic multimorbidity, such as asthma and eczema. The purpose of this investigation was to compare subjects with only rhinitis to those that have rhinitis, asthma and/or eczema in relation to immunoglobulin E (IgE) sensitization, inflammatory markers, family history, lung function and body mass index (BMI).

METHODS

A total of 216 adult subjects with rhinitis from the European Community Respiratory Health Survey II were investigated with multiplex component allergen analysis (103 allergen components), total IgE, C-reactive protein, eosinophilic cationic protein, fractional exhaled nitric oxide and spirometry. Rhinitis, eczema, asthma and parental allergy were questionnaire-assessed.

RESULTS

Of the 216 participants with rhinitis, 89 also had asthma and/or eczema. Participants with rhinitis that also had asthma or eczema were more likely to be IgE-sensitized (3.44, odds ratio, OR: 95% CI 1.62-7.30, adjusted for sex, age, mother's allergy, total IgE and forced expiratory volume (FEV1)). The number of IgE-positive components was independently associated with atopic multimorbidity (1.11, OR: 95% Cl 1.01-1.21) adjusted for sex, age, mother's allergy, total IgE and FEV1. When analysing different types of sensitization, the strongest association with atopic multimorbidity was found in participants that were IgE-sensitized both to perennial and seasonal allergens (4.50, OR: 95% CI 1.61-12.5). Maternal allergy (2.75, OR: 95% CI 1.15-4.46), high total IgE (2.38, OR: 95% CI 1.21-4.67) and lower FEV1 (0.73, OR: 95% CI 0.58-0.93) were also independently associated with atopic multimorbidity, while no association was found with any of the other inflammatory markers.

CONCLUSION

IgE polysensitization, to perennial and seasonal allergens, and levels of total IgE seem to be the main determinants of atopic multimorbidity in subjects with rhinitis. This indicates that disease-modifying treatment that targets IgE sensitization may be of value when decreasing the risk of developing atopic multimorbidity.

Effects of indoor coal fine particulate matter on the expression levels of inflammatory factors in ovalbumin-induced mice

Objective: Cooking and heating with coal is the main source of household air pollution in acid rain-plagued areas of China and is a leading contributor to disease burden. In this study, we investigated the adverse effects of exposure to indoor fine particulate matter emission from coal combustion on the expression levels of inflammatory factors in ovalbumin (OVA)-induced mice. Methods: Forty BALB/c male mice were randomly divided into four groups (control group, PM2.5 group, OVA group, and OVA + PM2.5 group; n = 10) and treated with ovalbumin (OVA) or PM2.5, alone or together. Interleukin-4 (IL-4), interleukin-7 (IL-7), interleukin-8 (IL-8), interleukin-17 (IL-17), transforming growth factor β1 (TGF-β1), and interferon γ (IFN-γ) protein expression levels were measured in bronchoalveolar lavage fluid (BALF). Additionally, serum immunoglobulin (Ig) IgE and IgG1 levels were measured. The mRNA expression levels of IL-7 and IFN-γ in pulmonary tissue were also analyzed. Bronchoalveolar lavage (BAL), inflammatory cell counts, and histopathological examinations were also performed. Results: Exposure to PM2.5 + OVA induced abnormal pathological changes and inflammatory responses in lungs compared to the control. The levels of IL-4, IL-7, IL-8 and IL-17 in BALF from the OVA + PM2.5 group were higher than those in BALF from the control group, OVA group, and PM2.5 group (P < 0.05). PM2.5 plus OVA significantly raised the serum IgE and IgG1 levels compared with the control group. An increasing IL-7 mRNA trend was found among the treatment groups (P < 0.05). The expression level of IFN-γ mRNA was significantly higher in the control group than in the other 3 groups (P < 0.05). Conclusion: Indoor coal PM2.5 was sufficient by itself to cause inflammatory cellular infiltration of pulmonary tissue, leading to organelle injury and physiological structure change. Additionally, it promoted the occurrence and development of asthma by influencing the expression levels of IL-7 and various relevant inflammatory factors (such as IL-4 and IL-8) and changing the equilibrium between Treg and Th17 cells.