Dust Mite Research Articles

Retrospective Evaluation of Clinical Characteristics of Children with Cat Sensitivity

Aims: Cat allergy has an important place among allergic diseases and it is known that environmental factors as well as genetic factors affect sensitisation. It has been reported that having a cat at home increases the risk of sensitisation, especially in susceptible individuals. The aim of this study was to retrospectively evaluate the clinical features of cat sensitisation in children. Methods: In this descriptive retrospective study, children aged 0-18 years with cat sensitisation who were admitted to the clinic between June 2023 and December 2023 were examined. Clinical characteristics, total IgE, eosinophil count, specific IgE values and skin prick test results were retrospectively evaluated using data obtained from the hospital database. Results: The study included 76 children with cat sensitisation. The mean age was 7 years and 56.6% were male. The most common diagnoses were asthma (63.2%) and allergic rhinitis (31.6%). Cat sensitisation was positive in 100% of the patients, house dust mite sensitisation was found in 78.9% and pollen sensitisation in 14.5%. Total IgE levels of patients with multiple allergies were significantly higher than those without multiple allergies. Conclusion: The study showed that additional allergen sensitisation was common in children with cat sensitisation and the most common diagnoses were allergic rhinitis and asthma. The findings are consistent with the existing literature and emphasise the importance of total IgE in the clinical management of allergic diseases.

STING-dependent induction of neutrophilic asthma exacerbation in response to house dust mite.

Severe refractory, neutrophilic asthma remains an unsolved clinical problem. STING agonists induce a neutrophilic response in the airways, suggesting that STING activation may contribute to the triggering of neutrophilic exacerbations. We aim to determine whether STING-induced neutrophilic lung inflammation mimics severe asthma. We developed new models of neutrophilic lung inflammation induced by house dust mite (HDM) plus STING agonists diamidobenzimidazole (diABZI) or cGAMP in wild-type, and conditional-STING-deficient mice. We measured DNA damage, cell death, NETs, cGAS/STING pathway activation by immunoblots, N1/N2 balance by flow cytometry, lung function by plethysmography, and Th1/Th2 cytokines by multiplex. We evaluated diABZI effects on human airway epithelial cells from healthy or patients with asthma, and validated the results by transcriptomic analyses of rhinovirus infected healthy controls vs patients with asthma. DiABZI administration during HDM challenge increased airway hyperresponsiveness, neutrophil recruitment with prominent NOS2+ARG1- type 1 neutrophils, protein extravasation, cell death by PANoptosis, NETs formation, extracellular dsDNA release, DNA sensors activation, IFNγ, IL-6 and CXCL10 release. Functionally, STING agonists exacerbated airway hyperresponsiveness. DiABZI caused DNA and epithelial barrier damage, STING pathway activation in human airway epithelial cells exposed to HDM, in line with DNA-sensing and PANoptosis pathways upregulation and tight-junction downregulation induced by rhinovirus challenge in patients with asthma. Our study identifies that triggering STING in the context of asthma induces cell death by PANoptosis, fueling the flame of inflammation through a mixed Th1/Th2 immune response recapitulating the features of severe asthma with a prognostic signature of type 1 neutrophils.

Blocking the HIF-1α/glycolysis axis inhibits allergic airway inflammation by reducing ILC2 metabolism and function.

The role of lung group 2 innate lymphoid cell (ILC2) activation in allergic asthma is increasingly established. However, the regulatory mechanisms underlying hypoxia-inducible factor-1α (HIF-1α)-mediated glycolysis in ILC2-mediated allergic airway inflammation remain unclear. To investigate the role of the HIF-1α/glycolysis axis in ILC2-mediated allergic airway inflammation. Glycolysis and HIF-1α inhibitors were used to identify their effect on the function and glucose metabolism of mouse and human ILC2s invivo and vitro. Blocking glycolysis and HIF-1α in mice under interleukin-33 (IL-33) stimulation were performed to test ILC2 responses. Conditional HIF-1α-deficient mice were used to confirm the specific role of HIF-1α in ILC2-driven airway inflammation models. Transcriptomic, metabolic, and chromatin immunoprecipitation analyses were performed to elucidate the underlying mechanism. HIF-1α is involved in ILC2 metabolism and is crucial in allergic airway inflammation. Single-cell sequencing data analysis and qPCR confirmation revealed a significant upregulation of glycolysis-related genes, particularly HIF-1α, in murine lung ILC2s after IL-33 intranasal administration or injection. Treatment with the glycolysis inhibitor 2-deoxy-D-glucose (2-DG) and the HIF-1α inhibitor 2-methoxyestradiol (2-ME) abrogated inflammation by suppressing ILC2s function. Conditional HIF-1α-deficient mice showed reduced ILC2 response and airway inflammation induced upon IL-33 or house dust mite (HDM) stimulation. Transcriptome and metabolic analyses revealed significantly impaired glycolysis in lung ILC2s in conditional HIF-1α knockout mice compared to that in their littermate controls. Chromatin immunoprecipitation results confirmed the transcriptional downregulation of glycolysis-related genes in HIF-1α-knockout and 2-DG-treated mice. Furthermore, impaired HIF-1α/glycolysis axis activation is correlated with downregulated ILC2 in patients with asthma. The HIF-1α/glycolysis axis is critical for controlling ILC2 responses in allergic airway inflammation and has potential immunotherapeutic value in asthma.

Progranulin derivative attenuates lung neutrophilic infiltration from diesel exhaust particle exposure.

Air pollutants, such as diesel exhaust particles (DEPs), induce respiratory disease exacerbation with neutrophilic infiltration. Progranulin (PGRN), an epithelial cell and macrophage-derived secretory protein, is associated with neutrophilic inflammation. PGRN is digested into various derivatives at inflammatory sites and is involved in several inflammatory processes. PGRN and its derivatives likely regulate responses to DEP exposure in allergic airway inflammation. To investigate the role of PGRN and its derivatives in the regulation of responses to DEP exposure in allergic airway inflammation. A murine model of allergic airway inflammation was generated in PGRN-deficient mice, and they were simultaneously exposed to DEP followed by intranasal administration of full-length recombinant PGRN (PGRN-FL) and a PGRN-derived fragment (FBAC). Inflammatory status was evaluated by bronchoalveolar lavage fluid and histopathologic analyses. Human bronchial epithelial cells were stimulated with DEPs and house dust mites (HDMs), and the effect of FBAC treatment was evaluated by assessing various intracellular signaling molecules, autophagy markers, inflammatory cytokines, and intracellular oxidative stress. DEP exposure exaggerated neutrophilic inflammation, enhanced IL-6 and CXCL15 secretions, and increased oxidative stress in the murine model; this effect was greater in PGRN-deficient mice than in wild-type mice. The DEP-exposed mice with PGRN-FL treatment revealed no change in neutrophil infiltration and higher oxidative stress status in the lungs. On the contrary, FBAC administration inhibited neutrophilic infiltration and reduced oxidative stress. In human bronchial epithelial cells, DEP and HDM exposure increased intracellular oxidative stress and IL-6 and IL-8 secretion. Decreased nuclear factor erythroid 2-related factor 2 (Nrf2) expression and increased phosphor-p62 and LC3B expression were also observed. FBAC treatment attenuated oxidative stress from DEP and HDM exposure. FBAC reduced neutrophilic inflammation exaggerated by DEP exposure in a mouse model of allergic airway inflammation by reducing oxidative stress. PGRN and PGRN-derived proteins may be novel therapeutic agents in attenuating asthma exacerbation induced by air pollutant exposure.

Predictive value of Der p 2-specific IgE for subcutaneous immunotherapy in children with allergic rhinitis

Dermatophagoides pteronyssinus (Der p) subcutaneous immunotherapy (SCIT) has demonstrated efficacy in clinical trials of childhood allergic rhinitis (AR). Currently, there is a lack of some generally accepted biomarkers that may predict the clinical response to SCIT to eventually achieve personalized therapy. In this study, 28 children with AR received Der p SCIT for 26–30 months at baseline, and four efficacy endpoints, serum interleukin (IL)-5, periostin, Der p-specific IgE (sIgE), and Der p sIgG4, were measured by ELSIA. Clinical symptoms and characteristics were assessed by questionnaires, and the associations among periostin, Der p 2 sIgE and clinical efficacy were analyzed. The results showed that SCIT demonstrated a significant reduction in Der p 1 sIgE (P < 0.05) and Der p 2 sIgE (P < 0.01), an increase in Der p sIgG4 (P < 0.001) and an improvement in clinical efficacy at the fourth efficacy endpoint compared with that at baseline. A positive linear correlation was found in serum periostin and Der p sIgE (P < 0.05), Der p sIgG4 (P < 0.05), and clinical efficacy. Importantly, the concentration of serum Der p 2 sIgE showed a positive linear correlation with clinical efficacy and serum periostin (P < 0.05). These results suggest that SCIT can result in reduced type 2 cytokines and Der p sIgE and has long-term efficacy in children with AR. Der p 2 sIgE has a positive linear correlation with clinical efficiency and serum periostin and may be a useful biomarker for the prediction of SCIT.

Altered expression of long noncoding RNAs regulating neutrophilic inflammation in peripheral blood was associated with symptom severity in patients with house dust mite-induced allergic rhinitis

BackgroundLong noncoding RNAs (lncRNAs) have been implicated in a diverse array of human immune diseases; however, a comprehensive understanding of the expression and function of lncRNAs in the peripheral blood leukocytes of individuals suffering from house dust mite (HDM)-induced allergic rhinitis (AR) remains elusive.ObjectiveTo explore the potential roles and functions of long noncoding RNAs (lncRNAs) in the pathogenesis of AR.MethodsSequencing analysis was performed on peripheral blood leukocytes collected from patients with HDM-induced AR and healthy controls (HCs) to elucidate the expression patterns of lncRNAs. Differentially expressed (DE) lncRNAs were identified and validated, and further correlation analyses were conducted to explore their associations with visual analog scale (VAS) scores and cytokine levels in the serum and nasal secretions. Additionally, bioinformatics analyses were performed to predict the potential pathways influenced by DE lncRNAs. Finally, the diagnostic potential of these lncRNAs in AR was assessed via receiver operating characteristic (ROC) curve analysis.ResultsSignificant differences in the expression profiles of lncRNAs and mRNAs were detected between AR patients and HCs. Four lncRNAs were markedly upregulated in AR patients. AC011524.2 was positively correlated with nasal pruritus (r = 0.4492, P = 0.0411). AL133371.3 was positively correlated with runny nose (r = 0.4889, P = 0.0245). AC011524.2 was positively correlated with CXCL8 (r = 0.4504, P = 0.0035). AL133371.3 was significantly positively correlated with only IL-17 (r = 0.4028, P = 0.0100). IL-4 in the serum was positively related to IL-17 in the serum (r = 0.4163, P = 0.0002). CXCL5 in the serum was positively correlated with IFN-γ (r = 0.3336, P = 0.0354) in nasal secretions. The area under the curve (AUC) of the ROC curve resulting from the integration of the 4 lncRNAs exhibited a remarkable value of 0.940 for AR diagnosis.ConclusionsOur results identified several lncRNAs associated with AR symptoms and inflammatory cytokines. Specifically, AC011524.2 and AL133371.3 exhibited strong correlations with diverse AR manifestations and serum cytokines, suggesting their pivotal role in the pathogenesis of AR, likely via neutrophil- and Th17-related pathways. However, the precise underlying mechanisms are still elusive, necessitating further exploration.

Rank correlation between atopic comorbidity and laboratory parameters in allergic rhinitis

One of the current cutting-edge problems in allergy and ENT is the study of comorbidity in allergic rhinitis, which is the most common atopic disease among all other atopies. Two decades ago, a new endotype of the disease, local allergic rhinitis, was discovered. In the past, some patients with typical complaints of chronic nasal congestion, persistent runny nose, and other similar symptoms, did not display such characteristic diagnostic criteria as positive allergy skin tests and an increased value of serum total IgE and specific IgE antibodies. They were qualified by allergists and ENT specialists as individualists with non-allergic rhinitis and, accordingly, did not receive adequate treatment. However, their symptoms remained, prompting them to abuse decongestants and resulting in an increased burden on the cardiovascular system. This, along with the burden of concomitant pathology, including other atopies, can be considered a significant medical and social problem. With the purpose to study rank correlation between comorbidity and three laboratory biomarkers, 46 patients with allergic rhinitis were examined. The list of parameters included two routine items such as serum total IgE and eosinophilic cationic protein, and rarely studied IL-4 in skin exudate. Clinical analysis showed that significantly more often allergic rhinitis in patients was combined with bronchial asthma (in 39.1%, p 0.05), less often with food allergy (in 19.6%), atopic dermatitis (in 10.9%), insect allergy (in 8.7%), and allergic urticaria (in 4.5%). In one case, local perennial rhinitis was identified, accompanied by conventional seasonal rhinitis with a high content of serum total IgE and positive allergic skin tests with pollen allergens. Skin tests with household allergens, including house dust mite products, showed a negative result. This case was regarded as a manifestation of the so-called “double” allergic rhinitis. The Spearman correlation demonstrated a negative mean strength relationship between comorbidity and serum IgE and eosinophilic cationic protein (p 0.05). The seemingly paradoxical result can be interpreted quite logically, taking into account immunopathogenetic mechanisms of allergic inflammation. In particular, with an increase in the frequency of atopic comorbidity, the migration of eosinophils from the blood to sites of eosinophilic inflammation increases.

Improved quality control of allergen products: Assessing the molecular allergen composition by mass spectrometry.

Natural allergen sources contain a variety of allergens, against which allergic subjects have developed individual sensitization profiles. Ideal allergen products for skin prick testing (SPT) and allergen immunotherapy (AIT) should contain the complete set of allergens of the respective allergen sources to cover all sensitization profiles. However, commercially available allergen products were shown to vary regarding their allergen composition. The qualitative allergen composition of different SPT and AIT products produced from pollen of grasses, birch, mugwort and from house dust mites was assessed by a consistent high-resolution liquid chromatography-coupled tandem mass spectrometry method (LC-MS/MS). All major, mid-tier and most minor allergens were detected in each of the investigated three batches of SPT and AIT products, demonstrating the completeness of the allergen composition and a high degree of batch-to-batch consistency. This is the first study using a single consistent high-resolution LC-MS/MS method to provide solid data on the qualitative allergen composition of SPT and AIT products manufactured from various common allergen sources. The applied method showed high reliability in qualitative batch-to-batch consistency testing and can be performed fast and with high throughput. High-resolution LC-MS/MS is applicable for process development and quality control to ensure market availability of allergen products corresponding to the composition of the respective natural allergen sources.

Epicutaneous house dust mite (HDM)-induced skin lesions feature early activation of T helper 2 inflammatory and pruritogenic pathways in HDM-nonsensitised dogs.

Epicutaneously house dust mite-sensitised (HDM-S) healthy dogs are commonly used as canine atopic dermatitis (cAD) models; however, the exact mechanisms of HDM-induced AD immune activation in HDM-S and HDM-nonsensitised (NS) dogs remain unclear. To characterise the inflammatory and pruritogenic transcriptome of acute epicutaneous HDM-induced skin lesions at 6 h and 24 h in HDM-NS and HDM-S dogs; untreated skin at 0 h from each dog served as control. Six HDM-S and six HDM-NS laboratory beagles. Processed expression data from GEO deposited by Schamber etal. (G3 (Bethesda), 2014, 4 and 1787) (GSE58442) were downloaded and analysed using R and the Bioconductor package. Significance analysis was performed with the limma package; genes with false discovery rate <0.05 and fold-change ≤/≥1.5 were considered significantly differentially expressed (DEGs). A 2D principal component analysis revealed no clear separation between HDM-NS and HDM-S dogs at 6 h and 24 h time points. HDM-induced skin lesions in sensitised and nonsensitised dogs at the 24 h time point showed significant upregulation of T helper cell (Th)2 genes (interleukin [IL]-4R, IL-5, IL-13, CCL13 and CCL17), as well as proinflammatory- (LTB, IL-1A and IL-18), Th1- (CXCL10, OASL and MX-1) and Th17-related markers (IL-17B, IL-17F, CCL19 and CCL20). The key Th22-related maker, IL-22, was upregulated only in the HDM-S group at the 24 h time point. Both groups at 24 h featured significant upregulation of several noncytokine pruritogens, such as trypsin, chymase, cathepsin S, periostin and neuromedin B. Taken together, we establish that epicutaneous HDM patch application induces immune changes in HDM-NS dogs with Th2 dominance and activates several itch-promoting pathways.

Aging, brain-derived neurotrophic factor, and allergen-induced pulmonary responses in mice.

Asthma in the elderly is being recognized as more severe, resistant to standard therapies, and having greater morbidity. Therefore, it comes important to understand the impact of aging-associated airway structure and function changes towards pathogenesis of asthma in the elderly. Here, airway smooth muscle plays important roles in airway hyperreactivity and structural remodeling. The role of smooth muscle in asthma can be modulated by growth factors (including neurotrophins such as brain-derived neurotrophic factor (BDNF)) and pro-inflammatory senescence factors. In this study, we investigated aging effects on airway hyperreactivity, structural remodeling, inflammation, and senescence in a mouse model of allergic asthma. C57BL/6J wildtype mice or smooth muscle-specific BDNF knockout mice at 4, 18 and 24 months of age were intranasally exposed to mixed allergens (ovalbumin, aspergillus, Alternaria, and house dust mite) over 4 weeks. Assessing lung function by FlexiVent, we found that compared with 4 month old mice, 18 and 24 month old C57BL/6J mice showed decreased airway resistance and increased airway compliance after PBS or MA treatment. Deletion of smooth muscle BDNF blunted airway hyperreactivity in aged mice. Lung histology analysis revealed that aging increased bronchial airway thickness and decreased lung inflammation. Multiplex assays showed that aging largely reduced allergen-induced lung expression of proinflammatory chemokines and cytokines. By immunohistochemistry staining, we found that aging increased bronchial airway expression of senescence markers, including p21, phospho-p53 and phospho-gH2A.X. Our data suggest that aging associated increase of airway senescence in the context of allergen exposure may contribute to asthma pathology in the elderly.

Gut microbiome impact on childhood allergic rhinitis and house dust mite IgE responses.

The correlation between the gut microbiota and airway inflammation in childhood allergic rhinitis (AR), particularly concerning allergen exposure, remains insufficiently explored. This study aimed to link gut microbiota changes with house dust mite (HDM)-specific IgE responses in pediatric AR. Using metagenomic shotgun sequencing, we compared the fecal microbiota of 60 children with HDM-AR to 48 healthy controls (HC), analyzing the link to IgE reactions. We examined the effects of oral Escherichia (E.) fergusonii treatment in mice sensitized with ovalbumin and HDM on allergic symptoms, mucosal cell infiltration, Th1/Th2/Tregs balance in the spleen, serum cytokine levels, and E. fergusonii presence in feces. Children with HDM-AR have a less diverse gut microbiome and lower levels of E. fergusonii compared to controls, with a negative correlation between E. fergusonii abundance and HDM-specific IgE levels. In mice sensitized with OVA and HDM, oral administration of E. fergusonii improved allergic symptoms, reduced nasal eosinophils/mast cells infiltration and adjusted Th cell populations towards a non-allergic profile in splenic lymphocytes with exception of IFN-γ change in serum. These findings underline the potential of targeting gut microbiota, particularly E. fergusonii, in managing childhood HDM-AR, suggesting a promising approach for future interventions. The composition and distribution of gut microbiota in children with HDM-AR are significant changed. The abundance of Escherichia genus is decreased in HDM-AR children. HDM-specific IgE levels are strongly negatively associated with E. fergusonii abundance. Oral administration of E. fergusonii effectively suppresses allergic responses in murine model. These findings offer novel insights into the diagnosis and treatment of HDM-AR, which suggested that E. fergusonii holds promise as a potential therapeutic avenue for managing HDM-AR.

Shikonin alleviates asthma phenotypes in mice via an airway epithelial STAT3-dependent mechanism.

Asthma is an inflammatory disease where the balance between Th1/Th2 and Th17/Treg plays a crucial role in its pathogenesis. Shikonin is used to treat a variety of autoimmune diseases due to its good anti-inflammatory activity. However, the effect and mechanism of shikonin on asthma remain unknown. Mice were sensitized with ovalbumin (OVA)/house dust mite (HDM) and treated with shikonin. Lung inflammation was assessed histologically and via flow cytometry. Bronchoalveolar lavage fluid (BALF) was analyzed for cell counts and cytokines. Shikonin's impact on p-STAT3 was studied in vivo and in vitro. Shikonin inhibited OVA or HDM-induced inflammation and airway hyperresponsiveness. Upon treatment, a restoration of the Th1/Th2 and Th17/Treg balance was observed, evidenced by a reduction in IL-4 and IL-17A levels in BALF, alongside an elevation in interferon-gamma and IL-10. Furthermore, shikonin impeded the infiltration of eosinophils, neutrophils, macrophages, and lymphocytes into lung tissue. The observed decrease in STAT3 phosphorylation and diminished nuclear translocation of p-STAT3 confirmed that shikonin promotes the balance of Th1/Th2 and Th17/Treg by regulating airway epithelial STAT3. Shikonin mitigates asthma symptoms through a STAT3-dependent mechanism, indicating its potential as an anti-asthmatic therapeutic agent.

Effect and mechanism of allergen-specific immunotherapy on small airway dysfunction in children with asthma.

The purpose of this study was to investigate the effectiveness of allergen-specific immunotherapy (AIT) on small airway dysfunction (SAD) and the underlying mechanism with a special focus on basophils. Sixty-five children with mild to moderate asthma who were under regular inhaled corticosteroid (ICS) treatment for more than 1 year but whose FEF75 remained below 65% of the predicted value and had positive results for serum Der p or Der f were enrolled. Children with asthma underwent house dust mite (HDM) subcutaneous immunotherapy (SCIT) treatment for 1 year. Clinical symptoms and lung function were evaluated every 3 months during HDM SCIT treatment. Basophil activation test (BAT) was carried out before and after HDM SCIT treatment. RNA sequencing was performed in isolated basophils from peripheral blood after 6 months of HDM SCIT treatment, followed by GO term and KEGG pathway enrichment analysis between patients with and without HDM SCIT treatment. HDM AIT treatment ameliorated clinical symptoms while concurrently improved lung function parameters, such as FEV1/FVC, FEF75, FEF50 and MMEF (p < .05). It is worth noting that FEF75 values showed a highly significant, gradual and persistent increase (from 49.55 ± 1.27% at baseline to 71.89 ± 2.64% after 1 year of therapy) and 22 of 35 patients no longer had SAD after 1 year of treatment. BAT results revealed that AIT treatment significantly reduced basophil activity to the inhalant allergen mixtures containing HDM in vitro challenge from baseline. GO term and KEGG pathway enrichment analysis of basophils revealed that downregulated genes were mainly involved in immune cell activation, antigen presentation, and Th2 cell differentiation. Our study demonstrated that HDM AIT not only improved SAD related lung function parameters, but also reduced basophil activity. RNA sequencing revealed the inhibition of phagocytosis and the phagosome pathway in basophils which may affect the polarization of Th2 cell differentiation after HDM AIT.

Airway macrophage glycolysis controls lung homeostasis and responses to aeroallergen.

The lungs represent a dynamic microenvironment where airway macrophages (AMs) are the major lung-resident macrophages. AMs dictate the balance between tissue homeostasis and immune activation and thus have contradictory functions by maintaining tolerance and tissue homeostasis, as well as initiating strong inflammatory responses. Emerging evidence has highlighted the connection between macrophage function and cellular metabolism. However, the functional importance of these processes in tissue-resident specialized macrophage populations such as those found in the airways, remain poorly elucidated. Here, we reveal that glycolysis is a fundamental pathway in AMs which regulates both lung homeostasis and responses to inhaled allergen. Using macrophage specific targeting in vivo, and multi-omics approaches, we determined that glycolytic activity in AMs is necessary to restrain type 2 (T2) immunity during homeostasis. Exposure to a range of common aeroallergens, including house dust mite (HDM), drove AM-glycolysis and furthermore, AM-specific inhibition of glycolysis altered inflammation in the airways and HDM-driven airway metabolic adaptations in vivo. Additionally, allergen sensitised asthmatics had profound metabolic changes in the airways, compared to non-sensitised asthmatic controls. Finally, we found that allergen driven AM-glycolysis in mice was TLR2 dependent. Thus, our findings demonstrate a direct relationship between glycolysis in AMs, AM-mediated homeostatic processes, and T2 immune responses in the lungs. These data suggest that glycolysis is essential for the plasticity of AMs. Depending on the immunological context, AM-glycolysis is required to exert homeostatic activity but once activated by allergen, AM-glycolysis influences inflammatory responses. Thus, precise modulation of glycolytic activity in AMs is essential for preserving lung homeostasis and regulating airway inflammation.

Hay Fever: Diagnosis and Management

Hay fever (allergic rhinitis) is a common condition with symptoms similar to those of a cold. It is an allergic reaction to environmental allergens such as pollens, dust mite, molds and animal dander. Avoiding allergic triggers and taking appropriate treatments are the best ways to reduce the frequency of hay fever symptoms.

Chrysene contribution to bronchial asthma: Activation of TRPA1 disrupts bronchial epithelial barrier via ERK pathway

BackgroundElevated polycyclic aromatic hydrocarbon (PAH) levels are associated with exacerbation of asthma. Chrysene is one of the most prevalent unsubstituted PAHs in the environment. Transient receptor potential ankyrin 1 (TRPA1) can be used as a chemoreceptor to detect inhaled stimuli and plays an important role in the occurrence and deterioration of asthma. Whether exposure to a high concentration of chrysene in the environment can activate TRPA1 and contribute to the development of asthma, potentially through the dysfunction of the bronchial epithelial barrier, remains unclear. MethodsA cell-based assay was performed to verify the downregulation of the expression of E-cadherin and tight junction (TJ) proteins by chrysene in bronchial epithelial cells to explore the role of chrysene-mediated TRPA1 activation in the regulation of TJ protein expression through the extracellular signal-regulated protein kinase (ERK) pathway. Animal tests were conducted to determine whether chrysene could enhance airway hyperresponsiveness (AHR) induced by house dust mites (HDMs) and disrupt barrier function, thereby contributing to asthma. ResultsThe cell-based assay revealed that chrysene could disrupt the function of the bronchial epithelial barrier and decrease the expression levels of E-cadherin, zonula occludens-1 (ZO-1), occludin, and claudin-5 through the ERK pathway. Chrysene induced airway epithelial barrier dysfunction primarily through TRPA1 instead of transient receptor potential vanilloid 1. TRPA1 knockdown was able to attenuate chrysene-induced downregulation of TJ protein expression and downregulate ERK activation (p-ERK). Compared with exposure to HDM alone, coexposure to chrysene and HDM resulted in an increased incidence of AHR, disruption of barrier function, and eosinophilic inflammatory responses in a mouse model of asthma. Coexposure to chrysene and HDM increased TRPA1 expression. The animal test verified that the TRPA1 inhibitor HC030031 could suppress chrysene and HDM-induced asthma in mice. ConclusionsOur findings showed that chrysene contributed to the breakdown of the function of the bronchial epithelial barrier through the TRPA1–ERK axis and therefore acted as an adjuvant to contribute to asthma.

MrgprA3+ Primary Sensory Neurons Mediate Acute Allergic Itch Responses in Atopic Dermatitis Model Mice.

Itch is a prominent symptom of atopic dermatitis (AD). However, the underlying mechanism remains complex and has not yet been fully elucidated. Mas-related G protein-coupled receptor A3 (MrgprA3) has emerged attention as a marker of primary sensory neurons that specifically transmit itch signals; however, its involvement in AD-related itch has not been extensively explored. In this study, we developed an AD itch mouse model by repeatedly applying house dust mite (HDM) extract to barrier-impaired skin via a special diet. To clarify the role of MrgprA3+ neurons in itch behavior in our AD model, we adopted a toxin receptor-mediated cell knockout strategy using transgenic mice in which the diphtheria toxin receptor (DTR) gene was placed under the control of the Mrgpra3 promoter. When the HDM extract was repeatedly applied to the face and back skin of special diet-fed mice, the mice exhibited AD-like dry and eczematous skin lesions accompanied by three types of itch-related behaviors:1) spontaneous scratching, 2) acute scratching after antigen challenge, and 3) light touch-evoked scratching. Upon diphtheria toxin administration, substantial depletion of DTR+/MrgprA3+ neurons was observed in the dorsal root ganglion. Ablation of MrgprA3+ neurons suppressed acute itch responses after HDM application, whereas spontaneous and touch-evoked itch behaviors remained unaffected. Our findings unequivocally demonstrate that in our AD model, MrgprA3+ primary sensory neurons mediate acute allergic itch responses, whereas these neurons are not involved in spontaneous itch or alloknesis.

Biological Sex Is an Effect Modifier of Allergen-Mediated Alteration of the Lung Proteome.

Asthma exhibits a distinct sex bias in the disease prevalence, severity, and response to therapy. However, sex-related differences in alterations of the lung proteome mediated by aeroallergens critical in asthma, such as house dust mites (HDM), remain unknown. In this study, we define sex-related differences in the lung proteome using an HDM-challenged mouse model by 1D LC-MS/MS. Sex-disaggregated data analysis showed that 406 proteins were uniquely altered in females, 273 proteins were uniquely altered in males, and 414 proteins were altered in both females and males in response to HDM. In a linear mixed model analysis, sex modified the HDM exposure effect for 163 proteins, i.e., a significant sex:exposure interaction was identified in 84 proteins in females and 35 proteins in males. Of these, 12 proteins showed a significant sex effect in both female and male lungs. We further selected 3 proteins Tjp1, Lamtor1, and G3BP2 for independent confirmation studies. Our findings detail the sex-specific lung proteome in response to an aeroallergen critical in asthma and demonstrate that sex is a significant effect modifier of HDM response. These results will serve as a valuable resource for delineating sex-specific mechanisms in aeroallergen-driven responses in asthma research.

The role of PAR2 in regulating MIF release in house dust mite-induced atopic dermatitis.

Atopic dermatitis (AD) is a chronic disease characterized by relapsed eczema and intractable itch, and is often triggered by house dust mites (HDM). PAR2 is a G-protein coupled receptor on keratinocytes and may be activated by HDM to affect AD processes. We first established a HDM-derived AD mouse model in wild-type (WT) and Par2-/- mice. Single cell RNA sequencing of the diseased skins found a stronger cellular communication between the ligand macrophage migration inhibitory factor (MIF) from keratinocytes and its receptors on antigen-presenting cells, suggesting the critical role of MIF in AD. HDM-WT mice showed severer skin lesions and pathological changes with stronger immunofluorescence MIF signals in skin sections than HDM-Par2-/- mice. Primary keratinocytes from WT mice stimulated with HDM or SLIGRL (PAR2 agonist) secreted more MIF in cultured medium and induced stronger immunofluorescence MIF signals than those from Par2-/- mice. The skin section of HDM-WT mice showed higher immunofluorescence signals of P115 (relating to MIF secretion) and KIF13B (possibly relating to intracellular trafficking of MIF) than that of HDM-Par2-/- mice. Acetylation of α-tubulin increased after stimulation by SLIGRL in WT keratinocytes but not in Par2-/- keratinocytes. HDM-WT mice treated with the MIF antagonist ISO-1 displayed improvement of AD-like presentations and lower expressions of IL-4, IL-13, TSLP and Arg1 (a biomarker of M2 macrophage) mRNAs. We conclude that MIF is an important cytokine and is significantly increased in the AD model. PAR2 affects AD changes by regulating the expression, intracellular trafficking, and secretion of MIF in epidermis.

B-059 Development and Validation of Multiplex Quantitative Allergy Tests based on Automated Flow Fluorescence Immunoassay Analyzer

Abstract Background Serological allergy tests measuring allergen-specific IgE (sIgE) are simpler and safer than skin prick tests, and the results are not influenced by skin condition or human factors. Quantitative detection of sIgE can also aid in evaluating patient allergies and aiding subsequent treatment. Dymind has researched and developed novel quantitative allergy tests based on the automated flow fluorescence immunoassay analyzer system (MF1280), enabling quantitative detection of multiple sIgE in just one test with one sample. Here, we present the performance of tIgE and two specific IgE test kits using the Dymind MF1280 system. Methods This study evaluated the performance of total IgE (tIgE) and two allergen-specific IgE (sIgE) panels of inhalant and food allergens, inhalant allergen panel including d1 (Dermatophagoides pteronyssinus), d2 (Dermatophagoides farina), i6 (Cockroach), e1 (Cat epithelium), e5 (Dog epithelium), w1(Common ragweed), and food allergen panel including f1 (Egg white), f2 (Cow’s milk), f3 (cod), f23 (Crab), 24 (Shrimp), and f27 (beef). Evaluation criteria included precision, linearity, limit of detection (LOD) and method comparison. As clinical performance of 425 clinical samples collected from 2 hospital laboratory in China was evaluated by both of Dymind allergen IgE MF1280 system and Phadia ImmunoCAP. Results The validated linearity of total IgE and sIgE were 2.0-5000.0 IU/mL and 0.1-100.0 IU/mL respectively. The LOD of total IgE and sIgE determined to be 2 IU/mL and 0.1 IU/mL respectively. The precision was evaluated by assaying a low and a high samples of every sIgE assay and the result of d1, d2, i6, e1, e5, w1, f1, f2, f3, f23, f24, f27 were 3.73% / 1.34% (low sample / high sample), 3.26% / 1.95%, 2.18% / 0.87%, 1.31% / 1.40%, 3.63% / 1.13%, 2.84% / 4.76%, 4.50% / 1.53%, 5.97% / 1.64%, 3.46% / 1.11%, 1.58% / 1.73%, 3.77% / 1.28%, 1.78% / 0.96% respectively. The total mean coefficient of measurements was below 7% to ensure high precision in multiplex quantitative analysis. Method comparison of 425 clinical samples between Phadia ImmunoCAP and Dymind allergen IgE showed total concordance rate was over 85% except f2 (over 80%). Conclusions The Dymind Allergen-specific IgE test kits on the automated flow fluorescence immunoassay analyzer system provide fast and accurate in vitro diagnostic detection of tIgE and sIgE for aiding diagnostics specific allergens sensitization and treatment for allergy patients, with good precision and excellent agreement compared to ImmunoCAP. The MF1280 system has advantages including random access, fully automated, multiplex quantitative detection of allergen sIgE with reducing assay time, sample consumption and lower costs.