House dust mite allergy: Its innate immune response and immunotherapy

Enhancing quality of life with 3-year course of sublingual immunotherapy for house dust mite-induced allergic rhinitis: An observational prospective study in real-life settings

PURPOSE

This prospective study aims to provide further supportive evidence by assessing the sustained effectiveness and safety of sublingual immunotherapy (SLIT) using a vaccine containing house dust mite (HDM) extracts in patients diagnosed with allergic rhinitis (AR) with/without conjunctivitis (AR/C).

MATERIALS AND METHODS

AR/C patients (n = 111, SLIT group: 57, control group: 54) allergic to HDM were treated with standardized SLIT drops or symptomatic drugs from October to December in 2020. The patients were directed by the investigators to attend annual hospital visits for the assessment of various parameters including the Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ), visual analog scale (VAS), total nasal symptom score (TNSS), total ocular symptom score (TOSS) and total medication score (TMS). During the study period, all participants were mandated to maintain comprehensive records of any adverse events (AEs) on diary cards, which were then communicated to the investigators via telephone.

RESULTS

At baseline (2020), TNSS, TOSS, TMS, VAS, and RQLQ scores were comparable between SLIT and control groups (P > 0.05). After one year of treatment (2021), significant reduction in all scores compared to the baseline for both groups (P < 0.001). At the end of the second year of treatment (2022), TNSS and RQLQ score in the SLIT group continued to decrease significantly compared to 2021 (P < 0.05). In the third year (2023), the control group showed a rebound in TNSS, TOSS, TMS, and RQLQ scores, significant differences compared to 2022 or 2021 (P < 0.05). Besides, the SLIT group had significantly lower scores across all domains of RQLQ compared to the control group (P < 0.001). Symptomatic treatment influenced the scores of Nasal Symptoms, Eye Symptoms, Practical Problems, and Emotions domains significantly in 2023 compared to 2021 or 2022 (P < 0.05). Within the SLIT group, no significant differences in TNSS, TMS, VAS, and RQLQ scores were observed between monosensitized and polysensitized patients throughout the three years of treatment (P > 0.05). All AEs were mild to moderate.

CONCLUSION

The 3-year course of HDM-SLIT has shown significant therapeutic efficacy and a favorable safety profile in patients with AR/C. Importantly, our study presents initial evidence suggesting that the greater impact of AR/C on quality of life (QoL) may primarily stem from nasal symptoms, eye symptoms, practical issues, and emotional well-being.

Biomarkers in allergen immunotherapy: Focus on eosinophilic inflammation

Asthma and allergic rhinitis (AR) are 2 of the most common chronic inflammatory disorders and they appear to be on the rise. Current pharmacotherapy effectively controls symptoms but does not alter the underlying pathophysiology. Allergen immunotherapy (AIT) is an evidence-based therapy for asthma and AR and has been recognized as the only therapeutic method that actually modifies the allergic disease process. There is a lack of objective markers that accurately and reliably reflect the therapeutic benefits of AIT. A biomarker indicating patients that would benefit most from AIT would be invaluable. Eosinophilic inflammation is a cardinal feature of many allergic diseases. Biomarkers that accurately reflect this inflammation are needed to better diagnose, treat, and monitor patients with allergic disorders. This review examines the current literature regarding AIT's effects on eosinophilic inflammation and biomarkers that may be used to determine the extent of these effects.

Multicenter study of seasonal and regional airborne allergens in Chinese preschoolers with allergic rhinitis

This study is nationwide multicenter epidemiological research, aimed at investigating the distribution changes and seasonal patterns of various airborne allergens among preschool children with allergic rhinitis (AR) in different regions of China, and analyzing the clinical correlation between sensitization to various airborne allergens and AR symptoms in children. Information on children was collected through standard questionnaires, and total IgE (tIgE) and specific IgE (sIgE) for 11 inhalant allergens were tested. The results showed that dust mites are the primary allergens for preschool AR children (39%). Among pollen allergens, Amb a had the highest positivity rate (8.1%), followed by Art v (7.8%). The sensitization rates for two mites peaked in May (46.9% and 40.6%). Art v peaked in August (21.5%), while Amb a had peaks in May (12.7%) and August (17.8%). The sensitization peaks for various tree pollens mainly occurred in August. In the Eastern monsoon region, the sensitization rate to mites was significantly higher than in the Northwest arid and semi-arid regions; whereas, for pollen allergens, the sensitization rates to Amb a, Pla a, Pin a, Pop d, and Bet v were significantly higher in the Northwest arid and semi-arid regions than in the Eastern monsoon region. The correlation among various tree pollens, specifically between Pla a, Pin r, Pop d, and Bet v was strong (0.63 ~ 0.79), with a cross-overlapping percentage of 53.9%. Children with multiple pollen sensitizations had higher cumulative nasal symptom scores than those negative for pollen (P < 0.01). Children with only pollen sensitization had higher cumulative rhinitis symptom scores than the all-negative group (P < 0.0001) and the mite-only sensitization group [P < 0.05], while the mite-only sensitization group also had higher scores than the all-negative group [P < 0.05], and the group sensitized to both pollen and mites had lower scores than the pollen-only group [P < 0.05]. This study indicates that sensitization to mites and grass pollens exhibits significant regional differences, with grass pollen allergies primarily occurring in autumn, sensitization to pollens in general exhibits a pronounced seasonal pattern. Moreover, pollen sensitization aggravates nasal and ocular symptoms in AR children.

Natural killer cells contribute to 'hot' tumor regression in the allergic inflammatory environment

Systemic immune status influences the elimination of tumor cells. However, it remains unclear how chronic inflammation in allergic diseases affects the tumor microenvironment and tumorigenesis. To investigate tumor progression in a state of heightened allergic inflammation, we established a mouse model of allergic inflammation. We used house dust mite extract to induce a hyper-reactive systemic immune response. Additionally, we subcutaneously inoculated two types of cancer cells (CT26 and 4T1 tumors). We conducted immune profiling of the ex-vivo tumor mass using multicolor flow cytometry staining and performed dynamic analysis of peripheral cytokines to explore the significant relationship between the development of allergic inflammation and tumorigenesis. We found that mice in a state of allergic inflammation were more susceptible to developing tumors. Interestingly, the growth of T cell-inflamed was inhibited in the allergic state, while growth of non-T cell-inflamed was promoted. Further research revealed that natural killer (NK) cells with enhanced tumor-killing or immune-regulating abilities were more active in " hot " tumors. Inhibiting NK cell activity can partially alleviate the impact of allergic inflammation on tumor growth. In summary, our results suggest that NK cells play significant role in suppressing tumor growth in an allergic inflammation mouse model. This phenomenon seems to be closely linked to both the inherent characteristics of the tumor and its interaction with the immune system. The innate immune system can be mobilized to synergize with the adaptive immune system to inhibit tumor growth, which opens a new way for a tumor immunotherapy.

Inhibitory effect of Sanguisorba hakusanensis Makino ethanol extract on atopic dermatitis-like responses in NC/Nga mice and human keratinocytes

Atopic dermatitis (AD) is an allergic, inflammatory skin disease caused by immune dysregulation. In this study, we investigated anti-atopic and anti-inflammatory activities of Sanguisorba hakusanensis ethanol extract (SHE) both in vivo using NC/Nga mice and in vitro using human HaCaT keratinocytes. Oral administration of SHE suppressed several atopic symptoms associated with house dust mites (induced with Dermatophagoides farinae extract) in NC/Nga mice and decreased serum levels of inflammatory mediators such as immunoglobulin E, histamine, and inflammatory chemokines. Additionally, SHE treatment reduced the infiltration of immune cells such as mast cells and macrophages in AD skin lesions. In vitro, interferon-γ- and tumor necrosis factor-α-stimulated HaCaT cells exhibited increased expression of T helper 1 and 2 chemokines; their expression was inhibited by SHE treatment. The anti-inflammatory effects of SHE treatment involved blocking of the mitogen-activated protein kinase and signal transducer and activator of transcription 1 signaling pathways. In conclusion, SHE exerts potent anti-atopic and anti-inflammatory effects and should be considered for the clinical treatment of AD.

Murine model identifies tropomyosin as IgE cross-reactive protein between house dust mite and coho salmon that possibly contributes to the development of salmon allergy

Background

Recently, we have developed a method to identify IgE cross-reactive allergens. However, the mechanism by which IgE cross-reactive allergens cause food allergy is not yet fully understood how. In this study, we aimed to understand the underlying pathogenesis by identifying food allergens that cross-react with house dust mite allergens in a murine model.

Material and methods

Allergenic protein microarray analysis was conducted using serum from mice intraperitoneally injected with Dermatophagoides pteronyssinus (Der p) extract plus alum or alum alone as controls. Der p, Dermatophagoides farinae (Der f), coho salmon extract-sensitized and control mice were analyzed. Serum levels of IgE against Der p, Der f, coho salmon extract, protein fractions of coho salmon extract separated by ammonium sulfate precipitation and anion exchange chromatography, and recombinant coho salmon tropomyosin or actin were measured by an enzyme-linked immunosorbent assay. A murine model of cutaneous anaphylaxis or oral allergy syndrome (OAS) was established in Der p extract-sensitized mice stimulated with coho salmon extract, tropomyosin, or actin.

Results

Protein microarray analysis showed that coho salmon-derived proteins were highly bound to serum IgE in Der p extract-sensitized mice. Serum IgE from Der p or Der f extract-sensitized mice was bound to coho salmon extract, whereas serum IgE from coho salmon extract-sensitized mice was bound to Der p or Der f extract. Analysis of the murine model showed that cutaneous anaphylaxis and oral allergic reaction were evident in Der p extract-sensitized mice stimulated by coho salmon extract. Serum IgE from Der p or Der f extract-sensitized mice was bound strongly to protein fractions separated by anion exchange chromatography of coho salmon proteins precipitated with 50% ammonium sulfate, which massively contained the approximately 38 kDa protein. We found that serum IgE from Der p extract-sensitized mice was bound to recombinant coho salmon tropomyosin. Der p extract-sensitized mice exhibited cutaneous anaphylaxis in response to coho salmon tropomyosin.

Conclusion

Our results showed IgE cross-reactivity of tropomyosin between Dermatophagoides and coho salmon which illustrates salmon allergy following sensitization with the house dust mite Dermatophagoides. Our method for identifying IgE cross-reactive allergens will help understand the underlying mechanisms of food allergies.

CircARF3 Mitigates Allergic Rhinitis through Targeting microRNA-205-5p/Sirtuin 5 Axis

INTRODUCTION

Circular RNAs (circRNAs) are essential in the progression of allergic rhinitis (AR). The purpose of this research was to examine the role of circRNA ADP-ribosylation factor 3 (circARF3) in the pathogenesis of AR.

METHODS

To generate an animal model of AR, mice were treated with house dust mite (HDM), and mice nasal epithelial cells (NEpCs) were treated with IL-4/IL-13 to imitate the inflammatory damage of AR in vitro. Sanger sequencing, qRT-PCR, and RNAse R digestion assays all validated the circularization structure of circARF3. The levels of circARF3, miR-205-5p, and sirtuin 5 (SIRT5) were determined by qRT-PCR or Western blotting. Luciferase reporter, RNA immunoprecipitation, and pull-down experiments were used to investigate the regulatory network. Flow cytometry was used to investigate the rate of cell apoptosis, and Western blotting was used to determine the levels of apoptotic-related proteins (cleaved caspase 3, cleaved polyadenosine-diphosphate-ribose polymerase) and HMGB1, TLR4, and MyD88. Enzyme-linked immunosorbent assay was used to assess the inflammatory response. Hematoxylin-eosin staining and TUNEL were used to detect the histology of injury and apoptosis of nasal mucosa tissues.

RESULTS

CircARF3 and SIRT5 levels were reduced in HDM-treated animals and IL-4/IL-13-treated NEpCs, while miR-205-5p expression was increased. CircARF3 was generated by back-splicing exons 3-5 with a stable circular shape. CircARF3 overexpression mitigated IL-4/IL-13-induced apoptosis in NEpCs by inhibiting miR-205-5p. SIRT5 upregulation attenuated IL-4/IL-13-induced inflammatory injury in NEpCs, and SIRT5 knockdown induced opposite effects. miR-205-5p silencing reversed the effects of SIRT5 knockdown on IL-4/IL-13-induced inflammatory injury. Furthermore, circARF3 overexpression alleviated histological abnormalities, apoptosis, inflammatory response, and HMGB1/TLR4 signaling activation in HDM-treated animals.

CONCLUSION

CircARF3 inhibited cell apoptosis and inflammation via the miR-205-5p/SIRT5 axis in IL-4/IL-13-treated NEpCs and HDM-treated mice.

Structure-function relationship and impact on the gut-immune barrier function of non-digestible carbohydrates and human milk oligosaccharides applicable for infant formula

Human milk oligosaccharides (hMOs) in mothers' milk play a crucial role in guiding the colonization of microbiota and gut-immune barrier development in infants. Non-digestible carbohydrates (NDCs) such as synthetic single hMOs, galacto-oligosaccharides (GOS), inulin-type fructans and pectin oligomers have been added to infant formula to substitute some hMOs' functions. HMOs and NDCs can modulate the gut-immune barrier, which is a multiple-layered functional unit consisting of microbiota, a mucus layer, gut epithelium, and the immune system. There is increasing evidence that the structures of the complex polysaccharides may influence their efficacy in modulating the gut-immune barrier. This review focuses on the role of different structures of individual hMOs and commonly applied NDCs in infant formulas in (i) direct regulation of the gut-immune barrier in a microbiota-independent manner and in (ii) modulation of microbiota composition and microbial metabolites of these polysaccharides in a microbiota-dependent manner. Both have been shown to be essential for guiding the development of an adequate immune barrier, but the effects are very dependent on the structural features of hMO or NDC. This knowledge might lead to tailored infant formulas for specific target groups.

Allergic rhinitis behavioral changes after Indonesian house dust mites allergenic extract administration as immunotherapy

Background: Allergy is a hypersensitivity reaction that is generally mediated by Immunoglobulin E (IgE). More than 25% of the world’s population is suspected of having these various diseases, and the prevalence and progression of these diseases have continued to increase significantly in recent years. Among these allergy-related diseases, allergic rhinitis and food allergy are the types of allergies with the highest prevalence. Clinical manifestations of allergic rhinitis include sneezing, rhinorrhea, nasal itching, and nasal congestion. Objective: This study aimed to determine the behavioral changes of allergic rhinitis after Indonesian House Dust Mites (IHDM) allergenic extract administration as an immunotherapy. Methods: Eight male BALB/c mice aged 6-8 weeks in each group were treated for seven groups. The sensitization phase is given intraperitoneal, the desensitization phase is given by subcutaneous, and the challenge phase is given intranasal. The allergic parameters were observed, such as nose rubbing and sneezing. The parameters were observed for 15 minutes after the challenge administration. Results: The results showed that the administration of Indonesian House Dust Mites as immunotherapy decreased the frequency of nose rubbing and sneezing after the administration of immunotherapy compared to the allergic rhinitis model. Conclusions: The administration of the Indonesia House Dust Mites as immunotherapy decreased the allergic rhinitis immune response by altering the behavioral parameter.

Serological analysis of allergic components of house dust mite provides more insight in epidemiological characteristics and clinical symptom development in North China

Background

House dust mite (HDM) is the most common airborne source causing complex allergy symptoms. There are geographic differences in the allergen molecule sensitization profiles. Serological testing with allergen components may provide more clues for diagnosis and clinical management.

Objective

This study aims to investigate the sensitization profile of eight HDM allergen components in a large number of patients enrolled in the clinic and to analyze the relation of gender, age, and clinical symptoms in North China.

Methods

The 548 serum samples of HDM-allergic patients (ImmunoCAP^® d1 or d2 IgE ≥0.35) were collected in Beijing City and divided in four different age groups and three allergic symptoms. The specific IgE of HDM allergenic components, Der p 1/Der f 1, Der p 2/Der f 2, Der p 7, Der p 10, Der p 21, and Der p 23, was measured using the micro-arrayed allergen test kit developed by Hangzhou Zheda Dixun Biological Gene Engineering Co., Ltd. The new system was validated by comparing to single-component Der p 1, Der p 2, and Der p 23 tests by ImmunoCAP in 39 sera. The epidemiological study of these IgE profiles and the relation to age and clinical phenotypes were analyzed.

Results

A greater proportion of male patients was in the younger age groups, while more female patients were in the adult groups. Both the sIgE levels and the positive rates (approximately 60%) against Der p 1/Der f 1 and Der p 2/Der f 2 were higher than for the Der p 7, Der p 10, and Der p 21 components (below 25%). The Der f 1 and Der p 2 positive rates were higher in 2-12-year-old children. The Der p 2 and Der f 2 IgE levels and positive rates were higher in the allergic rhinitis group. The positive rates of Der p 10 increased significantly with age. Der p 21 is relevant in allergic dermatitis symptom, while Der p 23 contributes to asthma development.

Conclusion

HDM groups 1 and 2 were the major sensitizing allergens, with group 2 being the most important component relevant to respiratory symptoms in North China. The Der p 10 sensitization tends to increase with age. Der p 21 and Der p 23 might be associated with the development of allergic skin disease and asthma, respectively. Multiple allergen sensitizations increased the risk of allergic asthma.

Screening of B-cell epitopes of Der-p1 and Der-p2 major aeroallergens by computational approach for designing immunotherapeutics

Introduction and Aim: Allergic diseases are IgE-mediated hypersensitivity reactions affecting approximately 30% of the general population globally. Dermatophagoides pteronyssinus (Der-p) is the most prevalent house dust mite (HDM) species consisting of 23 mite allergen groups. Among these, group 1 and 2 are major allergenic proteins, which causes allergic asthma in 80% of sensitized individuals, with elevated IgE titres in the serum. This study involves in silico analysis of potential B-cell epitopes of group 1 and group 2 of Der-p, which can be utilized in designing immunotherapeutic vaccines.   Materials and Methods: Allergen sequences obtained from the database- International Union of Immunological Societies (IUIS), for predicting of B-cell epitopes. The physiochemical properties and secondary structures of the obtained sequence were evaluated. The sequences were further subjected to determining antigenicity, surface accessibility, and prediction of linear and discontinuous B-cell epitope by utilizing IEDB tools.   Results: The linear and discontinuous B-cell epitopes of Der-p1 and Der-p2 aeroallergen were predicted. Further, Der-p1 and Der-p2 showed 6 linear epitopes each respectively. Conformational epitopes predicted were 123 of Der-p1 and 72 of Der-p2 respectively, by the ElliPro tool. Based on the structure, antigenicity, and surface accessibility, only 10% of Der-p1 and Der-p2 which binds to B-cell epitopes are linear and the majority are discontinuous.   Conclusion: The linear and conformational epitopes of Der-p1 and Der-p2 are predicted using in silico tools. These identified epitopes might be useful for developing epitope-based immunotherapeutics for HDM allergy.

Effectiveness of Indonesian house dust mite allergenic extract in triggering allergic rhinitis sensitivity in a mouse model: A preliminary study

Background and Aim:

Perennial allergic rhinitis (AR) is a chronic upper respiratory disease, with inflammation mediated by immunoglobulin E in the nasal mucosa caused by house dust mites. Recently, allergen immunotherapy showed promising allergic healing in patients with a definite history of sensitization. Based on this finding, a product was developed using Indonesian house dust mite (IHDM). This study aimed to optimize the allergenic rhinitis mouse model that was generated using IHDM to test the in vivo sensitivity and safety of this product.

Materials and Methods:

Seven groups of mice were used for effectiveness testing – normal, negative control with IHDM challenge, positive control with 0.1% histamine challenge, and AR group by both IHDM-induced sensitization at 12.5, 50, 250, or 500 μg and IHDM challenge. Mice were sensitized by intraperitoneal administration of IHDM once a week for 3 consecutive weeks. Thereafter, the challenge was given intranasally 5 times on alternate days. The number of nose rubbing and sneezing was noted. Eosinophil infiltration was assessed histologically using hematoxylin and eosin staining. The expression of interleukin-5 (IL-5) mRNA in the nasal mucosa was determined using semi-quantitative reverse transcription-polymerase chain reaction.

Results:

The induction of AR with IHDM significantly increased the number of nose rubbing and sneezing in the mouse model. Eosinophil infiltration was observed in the nasal mucosa; however, no significant change occurred in the expression of IL-5 mRNA.

Conclusion:

Overall, these data indicate that IHDM allergenic extract could be an effective sensitizing agent in a mouse model of AR. Although the use of IHDM is a limitation of this study because other sources of house dust mites might have different effects, this study provides a proper model for immunotherapy effectivity testing for in vivo pre-clinical studies.

House dust mite-induced Akt-ERK1/2-C/EBP beta pathway triggers CCL20-mediated inflammation and epithelial-mesenchymal transition for airway remodeling

House dust mite (HDM) allergens cause inflammatory responses and chronic allergic diseases such as bronchial asthma and atopic dermatitis. Here, we investigate the mechanism by which HDM induces C-C chemokine ligand 20 (CCL20) expression to promote chronic inflammation and airway remodeling in an HDM-induced bronchial asthma mouse model. We showed that HDM increased CCL20 levels via the Akt-ERK1/2-C/EBPβ pathway. To investigate the role of CCL20 in chronic airway inflammation and remodeling, we made a mouse model of CCL20-induced bronchial asthma. Treatment of anti-CCL20Ab in this mouse model showed the reduced airway hyper-responsiveness and inflammatory cell infiltration into peribronchial region by neutralizing CCL20. In addition, CCL20 induced the Nod-like receptor family, pyrin domain containing 3 (NLRP3) inflammasome activation through NLRP3 deubiquitination and transcriptional upregulation in BEAS-2B cells. As expected, anti-CCL20Ab markedly suppressed NLRP3 activation induced by CCL20. Moreover, HDM-induced CCL20 leads to epithelial-mesenchymal transition in the lung epithelium which appears to be an important regulator of airway remodeling in allergic asthma. We also found that anti-CCL20Ab attenuates airway inflammation and remodeling in an HDM-induced mouse model of bronchial asthma. Taken together, our results suggest that HDM-induced CCL20 is required for chronic inflammation that contributes airway remodeling in a mouse model of asthma.

Novel Approaches for Inhibiting the Indoor Allergen Der f 2 Excreted from House Dust Mites by Todomatsu Oil Produced from Woodland Residues

House dust mite (HDM) is a globally ubiquitous domestic cause of allergic diseases. There is a pressing demand to discover efficient, harmless, and eco-friendly natural extracts to inhibit HDM allergens that are more likely to trigger allergies and challenging to be prevented entirely. This study, therefore, is aimed at assessing the inhibition of the allergenicity of major HDM allergen Der f 2 by todomatsu oil extracted from residues of Abies Sachalinensis. The inhibition was investigated experimentally (using enzyme-linked immunosorbent assay (ELISA), surface plasmon resonance (SPR), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE)) and in silico using molecular docking. The results showed that todomatsu oil inhibits the allergenicity of Der f 2 by reducing its amount instead of the IgG binding capacity of a single protein. Moreover, the compounds in todomatsu oil bind to Der f 2 via alkyl hydrophobic interactions. Notably, most compounds interact with the hydrophobic amino acids of Der f 2, and seven substances interact with CYS27. Contrarily, the principal compounds fail to attach to the amino acids forming the IgG epitope in Der f 2. Interestingly, chemical components with the lowest relative percentages in todomatsu oil show high-affinity values on Der f 2, especially β-maaliene (-8.0 kcal/mol). In conclusion, todomatsu oil has been proven in vitro as a potential effective public health strategy to inhibit the allergenicity of Der f 2.

Microbiome profiling of nasal extracellular vesicles in patients with allergic rhinitis

Background

Methods

Results

Conclusion

KIF2A decreases IL-33 production and attenuates allergic asthmatic inflammation

Background

The microtubule-dependent molecular motor protein Kinesin Family Member 2A (KIF2A) is down-regulated in asthmatic human airway epithelium. However, little is known about the roles of KIF2A as well as the possible underlying mechanisms in asthma.

Methods

House dust mite (HDM) extract was administered to establish a murine model of asthma. The expression of KIF2A, IL-33 and the autophagy pathways were detected. The plasmid pCMV-KIF2A was used to overexpress KIF2A in the airway epithelial cells in vitro and in vivo. IL-4, IL-5, IL-33 and other cytokines in bronchoalveolar lavage fluid (BALF) and lung tissues homogenates were measured.

Results

In response to the challenge of house dust mite (HDM) in vitro and in vivo, airway epithelial cells displayed decreased production of KIF2A. Meanwhile, autophagy and IL-33 were increased in HMD-treated epithelial cells. Mechanistically, KIF2A decreased autophagy via suppressing mTORC1 pathway in HDM-treated epithelial cells, which contributed to the reduced production of IL-33. Moreover, in vivo KIF2A transfection reduced IL-33 and autophagy in the lung, leading to the attenuation of allergic asthma.

Conclusion

KIF2A suppressed mTORC1-mediated autophagy and decreased the production of epithelial-derived cytokine IL-33 in allergic airway inflammation. These data indicate that KIF2A may be a novel target in allergic asthma.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13223-022-00697-9.

Adolescent Scalp Dermatitis Associated with Dermatophagoides spp. (Acariformes; Pyroglyphidae) Mite

PURPOSE

Dermatophagoides spp. (Acariformes; Pyroglyphidae), house dust-mite well known as the causative agent of atopic hypersensitivity and allergy could potentially cause severe dermatitis. Herein we report an uncommon case of scalp dermatitis associated with the presence of Dermatophagoides spp.

METHODS

A 17-year old male presented with patchy alopecia on the scalp without intense peeling or itching, surround by unchanged skin and hair. Initially, superficial fungal infection was suspected; however, parasitological examination revealed the presence of live mites.

RESULTS

All the anatomical measurements and parameters from the specimens were compatible with Dermatophagoides spp.

CONCLUSIONS

Dermatophagoides spp. are not yet confirmed as causative agents of parasitic infestation, but the presence of these mites could have caused an allergic reaction followed by dermatitis with mild-to-moderate clinical manifestations. However, true parasitism as well as phoresy could also be considered. The clinical manifestations caused by house-dust mite cannot be easily recognized and the lack of diagnostic tools is a hindrance that often leads to misdiagnosis and inadequate therapy.

Efficacy and safety of crisaborole in patients with mild-to-moderate atopic dermatitis and other atopic comorbidities

Background: Crisaborole is a nonsteroidal anti-inflammatory phosphodiesterase 4 inhibitor that is approved for the treatment of patients with mild-to-moderate atopic dermatitis (AD); however, the efficacy and safety of crisaborole in patients with AD and other atopic comorbidities have not been investigated. Objective: This post hoc pooled analysis of the pivotal phase III studies (CrisADe CORE 1 and CORE 2) assessed the efficacy and safety of crisaborole versus vehicle in patients aged ≥ 2 years with mild-to-moderate AD and other atopic comorbidities. Methods: Patients with mild-to-moderate AD and a medical history of asthma, allergic rhinitis, or food allergies were identified. Efficacy assessments included the proportion of patients who achieved Investigator's Static Global Assessment (ISGA) success at day 29, ISGA clear or almost clear at day 29, and improvement in the Severity of Pruritus Scale score at week 4. Safety was assessed via treatment-emergent adverse events (TEAEs). Results: This analysis included 1522 patients (crisaborole, 1016; vehicle, 506); 26.2, 15.9, and 16.5% had a medical history of asthma, allergic rhinitis, and food allergies, respectively. The mean age was 12.2 years. A significantly greater proportion of patients treated with crisaborole achieved ISGA success at day 29 compared with patients treated with vehicle for most subgroups analyzed. Furthermore, a significantly greater proportion of patients treated with crisaborole achieved ISGA clear or almost clear at day 29 across all subgroups and demonstrated improvement in the Severity of Pruritus Scale score at week 4 versus patients treated with vehicle in most of the subgroups. Overall, most TEAEs were mild or moderate in severity; the most common treatment-related TEAE in patients with atopic comorbidities was application-site pain (crisaborole, 5.1%; vehicle, 1.7%). Conclusion: Crisaborole was efficacious and well tolerated in patients with mild-to-moderate AD and other atopic comorbidities, which suggested that crisaborole should be considered for the management of AD in this population. Clinical Trials NCT02118766 (CrisADe CORE 1) and NCT02118792 (CrisADe CORE 2), <ext-link xmlns:xlink="http://www.w3.org/1999/xlink" ext-link-type="uri" xlink:href="http://www.clinicaltrials.gov">www.clinicaltrials.gov</ext-link>.

Der f 38 Is a Novel TLR4-Binding Allergen Related to Allergy Pathogenesis from Dermatophagoides farinae

It is difficult to treat allergic diseases including asthma completely because its pathogenesis remains unclear. House dust mite (HDM) is a critical allergen and Toll-like receptor (TLR) 4 is a member of the toll-like receptor family, which plays an important role in allergic diseases. The purpose of this study was to characterize a novel allergen, Der f 38 binding to TLR4, and unveil its role as an inducer of allergy. Der f 38 expression was detected in the body and feces of Dermatophagoides farinae (DF). Electron microscopy revealed that it was located in the granule layer, the epithelium layer, and microvilli of the posterior midgut. The skin prick test showed that 60% of allergic subjects were Der f 38-positive. Der f 38 enhanced surface 203c expression in basophils of Der f 38-positive allergic subjects. By analysis of the model structure of Der p 38, the expected epitope sites are exposed on the exterior side. In animal experiments, Der f 38 triggered an infiltration of inflammatory cells. Intranasal (IN) administration of Der f 38 increased neutrophils in the lung. Intraperitoneal (IP) and IN injections of Der f 38 induced both eosinophils and neutrophils. Increased total IgE level and histopathological features were found in BALB/c mice treated with Der f 38 by IP and IN injections. TLR4 knockout (KO) BALB/c mice exhibited less inflammation and IgE level in the sera compared to wild type (WT) mice. Der f 38 directly binds to TLR4 using biolayer interferometry. Der f 38 suppressed the apoptosis of neutrophils and eosinophils by downregulating proteins in the proapoptotic pathway including caspase 9, caspase 3, and BAX and upregulating proteins in the anti-apoptotic pathway including BCL-2 and MCL-1. These findings might shed light on the pathogenic mechanisms of allergy to HDM.

Comparison of house dust mite sensitization profiles in allergic adults from Canada, Europe, South Africa and USA

BACKGROUND

Sensitization to house dust mite (HDM) is a leading cause of allergic rhinitis and asthma. Despite more than 30 HDM-derived allergens having been identified to date, specific therapeutic approaches do not yet take into account the local sensitization profiles of patients. This study aimed to identify patterns of HDM sensitization in HDM-allergic adults living in distinct geographic areas, to inform the development of targeted diagnostic and therapeutic tools.

METHODS

Serum samples from 685 HDM-allergic subjects from Canada, Europe, South Africa, and the USA were tested for levels of IgE specific for 17 micro-arrayed HDM allergens by ImmunoCAP Immuno Solid-phase Allergen Chip (ISAC) technology.

RESULTS

The results confirmed significant geographical variability in sensitization patterns and levels of IgE. In all areas, the major sensitizers were the group 1 and group 2 allergens and Der p 23. Der p 23 was a frequent sensitizer: 64% of the subjects had IgE specific for Der p 23, and 2.3% were monosensitized to it. In South Africa, Der p 23 was the dominant HDM allergen (86% prevalence) and Der p 7 achieved major allergen status (56%). IgE sensitization to HDM was influenced by asthmatic status, levels of allergen exposure, age, race-ethnicity and smoking status, but not by BMI.

CONCLUSION

Sensitization profiles to HDM allergens differ considerably among distinct geographic areas, with Der p 7 and Der p 23 being major sensitizers in South Africa. Such heterogeneity should be taken into account in the diagnosis and treatment of HDM-allergic patients.

Human Milk Oligosaccharides: Their Effects on the Host and Their Potential as Therapeutic Agents

Breastmilk is known to be very important for infants because it provides nutrients and immunological compounds. Among these compounds, human milk oligosaccharides (HMOs) represent the third most important component of breastmilk after lipids and lactose. Several experiments demonstrated the beneficial effects of these components on the microbiota, the immune system and epithelial barriers, which are three major biological systems. Indeed, HMOs induce bacterial colonization in the intestinal tract, which is beneficial for health. The gut bacteria can act directly and indirectly on the immune system by stimulating innate immunity and controlling inflammatory reactions and by inducing an adaptive immune response and a tolerogenic environment. In parallel, HMOs directly strengthen the intestinal epithelial barrier, protecting the host against pathogens. Here, we review the molecular mechanisms of HMOs in these different compartments and highlight their potential use as new therapeutic agents, especially in allergy prevention.

Human monocyte-derived type 1 and 2 macrophages recognize Ara h 1, a major peanut allergen, by different mechanisms

Evidence has suggested that major peanut allergen Ara h 1 activates dendritic cells (DCs) via interaction with DC-SIGN (dendritic cell-specific intercellular adhesion molecule-3-grabbing non-integrin), a C-type lectin receptor, and contributes to development of peanut allergy. Since macrophages, as well as DCs, play a crucial role in innate immunity, we investigated whether natural Ara h 1 (nAra h 1) activates two different subsets of macrophages, human monocyte derived macrophage type 1 (hMDM1: pro-inflammatory model) and type 2 (hMDM2: anti-inflammatory model). hMDM1 and hMDM2 predominantly produced pro-inflammatory cytokines (IL-6 and TNF-α) and an anti-inflammatory cytokine (IL-10) in response to nAra h 1, respectively. hMDM2 took up nAra h 1 and expressed DC-SIGN at higher levels than hMDM1. However, small interfering RNA knockdown of DC-SIGN did not suppress nAra h 1 uptake and nAra h 1-mediated cytokine production in hMDM2. Inhibitors of scavenger receptor class A type I (SR-AI) suppressed the response of hMDM2, but not of hMDM1, suggesting that SR-AI is a major receptor in hMDM2 for nAra h 1 recognition and internalization. nAra h 1 appears to exert stimulatory capacity on DC and macrophages via different receptors. This study advances our understanding how a major peanut allergen interacts with innate immunity.

Repeated exposure of house dust mite induces progressive airway inflammation in mice: Differential roles of CCL17 and IL-13

We conducted a systematic evaluation of lung inflammation indued by repeated intranasal exposure (for 10 consecutive days) to a human aeroallergen, house dust mite (HDM) in BALB/c mice. Peak influx of neutrophils, monocytes/lymphocytes, and eosinophils was observed in bronchoalveolar lavage (BAL) on days 1, 7 and 11, respectively, and normalized to baseline by day 21. Peak elevations of Th2, myeloid-derived cytokines/chemokines and serum IgE were seen both in BAL and lung tissue homogenates between days 7 and 11, and declined thereafter; however, IL-33 levels remained elevated from day 7 to day 21. Airway hyperreactivity to inhaled methacholine was significantly increased by day 11 and decreased to baseline by day 21. The lung tissue showed perivascular and peribronchial cuffing, epithelial hypertrophy and hyperplasia and goblet cell formation in airways by day 11, and resolution by day 21. Levels of soluble collagen and tissue inhibitors of metalloproteinases (TIMP) also increased reflecting tissue remodeling in the lung. Microarray analysis demonstrated a significant time-dependent up-regulation of several genes including IL-33, CLCA3, CCL17, CD4, CD10, CD27, IL-13, Foxa3, IL-4, IL-10, and CD19, in BAL cells as well as the lung. Pre-treatment of HDM challenged mice with CCL17 and IL-13 antibodies reduced BAL cellularity, airway hyper-responsiveness (AHR), and histopathological changes. Notably, anti-IL-13, but not anti-CCL17 monoclonal antibodies (mAbs) reduced BAL neutrophilia while both mAbs attenuated eosinophilia. These results suggest that CCL17 has an overlapping, yet distinct profile versus IL-13 in the HDM model of pulmonary inflammation and potential for CCL17-based therapeutics in treating Th2 inflammation.

Enolase-specific cross antibodies induce neutrophilic inflammation in the intestine

The pathogenesis of ulcerative colitis (UC) is to be further investigated. House dust mites (HDM) are highly associated with the pathogenesis of immune inflammation in the body. This study aims to investigate the role of enolase (one of the HDM-derived proteins)-specific cross Abs in the induction of UC-like inflammation. The enolase specific IgG (EsIgG) was identified in UC patients by mass spectrometry. Mice were treated with EsIgG to induce inflammation in the colon mucosa. EsIgG was detected in the serum and the colon tissues of UC patients, which was positively correlated with the polymorphonuclear neutrophil (PMN) counts in the blood and colon tissues of UC patients. EsIgG formed immune complexes with the constitutive enolase in the UC colon epithelium that activated complement, induced epithelial cell apoptosis, compromised epithelial barrier functions, and resulted in UC-like inflammation in the mouse colon. In summary, UC patients have high serum levels of Abs against HDM-derived enolase and intestinal epithelial cell-derived enolase. These Abs attack the colonic epithelium to induce UC-like inflammation.

Upregulated Expression of Toll-Like Receptor 7 in Peripheral Blood Basophils of Patients With Allergic Rhinitis

Background

Recently, it has been reported that Toll-like receptor 7 (TLR7) agonists can improve allergic rhinitis (AR) symptoms by up-regulation of Th1 cytokine release and suppression of Th2 cell functions. However, little is known of the expression of TLR7 in basophils of AR.

Objective

To explore the expression of TLR7 in basophils of AR, and influence of allergens on TLR7 expression.

Methods

The expression levels of TLR7 in basophils of patients with AR were determined by flow cytometry, and the influence of allergens on TLR7 expression was examined by real time (q) PCR.

Results

The percentages of TLR7+CCR3+ cells ( P < 0.001 and P = 0.011), TLR7+CD123+HLA-DR− cells ( P = 0 .016 and P = 0.042) and TLR7+CCR3+CD123+HLA-DR− cells ( P = 0.046 and P = 0.035) in blood granulocyte and mononucleated cell populations of the patients with AR were increased, respectively compared with HC subjects. TLR7 MFI on CCR3+ cells ( P = 0.050 and P = 0.043), CD123+HLA-DR− cells ( P < 0.001 and P = 0.002) and CCR3+CD123+HLA-DR− cells ( P < 0.001 and P = 0.003) were enhanced compared with HC subjects. Allergens Der p1 and OVA provoked upregulation of TLR7 expression at both protein and mRNA levels and IL-13 production in KU812 cells. House Dust Mite extract (HDME), Artemisia sieversiana wild allergen extract (ASWE), IL-31, IL-33, IL-37, and TSLP provoked elevation of IL-6 release from KU812 cells following 2 h incubation period.

Conclusions

The percentage of TLR7+ basophils and TLR7 expression intensity in a single basophil are both increased in the blood of patients with AR, indicating that basophils likely contribute to the pathogenesis of AR via TLR7.

House dust mites-driven allergic rhinitis: could its natural history be modified?

INTRODUCTION

Allergic rhinitis (AR) is the most common IgE-mediated disease. House dust mites (HDMs)-sensitization is the main cause of AR. HDM-driven AR is characterized by a typical natural history consisting of possible progression to asthma. Allergen Immunotherapy (AIT) is, at present, a unique treatment to modify the natural history of allergic diseases. Tablets AIT (TAIT) represents a new era in AIT. There is evidence that TAIT could prevent asthma in AR patients.

AREAS COVERED

The literature search methodology was based on the articles cited by PubMed from 1980 to 2020. AIT's rationale is to restore an immunological and, consequently, clinical tolerance toward the causal allergen. The progression from rhinitis to asthma may be influenced by a relevant risk factor, such as the persistent type 2 inflammation of airways. HDMs are perennial allergens and allergen exposure is the condicio sine qua non to maintain inflammation. AIT could modify the progression toward asthma restoring physiologic immune response to the causal allergen and consequently dampening type 2 inflammation.

EXPERT OPINION

Patients with HDM-driven AR are susceptible to develop asthma over time. Many studies explored this topic. Cross-sectional and longitudinal studies identified some markers which predict the risk of developing asthma. They include bronchial airflow limitation, bronchial hyperresponsiveness, type 2 inflammation, and rhinitis duration. TAIT could block this progression by acting on this vicious circle. Future studies should explore this issue using adequate methodology.

Immune Modulation of Allergic Asthma by Early Pharmacological Inhibition of RIP2

Exposure to house dust mite (HDM) is highly associated with the development of allergic asthma. The adaptive immune response to HDM is largely Th2 and Th17 dominant, and a number of innate immune receptors have been identified that recognize HDM to initiate these responses. Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) is a cytosolic sensor of peptidoglycan, which is important for Th2 and Th17 polarization. NOD2 mediates its signaling through its downstream effector kinase, receptor-interacting serine/threonine protein kinase 2 (RIP2). We have previously shown that RIP2 promotes HDM-associated allergic airway inflammation and Th2 and Th17 immunity, acting early in the HDM response and likely within airway epithelial cells. However, the consequences of inhibiting RIP2 during this critical period has not yet been examined. In this study, we pharmacologically inhibited RIP2 activity during the initial exposure to allergen in an acute HDM model of asthma and determined the effect on the subsequent development of allergic airway disease. We show that early inhibition of RIP2 was sufficient to reduce lung histopathology and local airway inflammation while reducing the Th2 immune response. Using a chronic HDM asthma model, we demonstrate that inhibition of RIP2, despite attenuating airway inflammation and airway remodeling, was insufficient to reduce airway hyperresponsiveness. These data demonstrate the potential of pharmacological targeting of this kinase in asthma and support further development and optimization of RIP2-targeted therapies.

Upregulation of the expression of Toll-like receptor 9 in basophils in patients with allergic rhinitis: An enhanced expression by allergens

It was reported that the expression of Toll-like receptor (TLR) 9 may be related to Th2-type allergic inflammation including allergic rhinitis (AR). However, little is known about the expression of TLR9 in the basophils in AR. In the present study, the expression of TLR9 was examined by flow cytometry analysis, and the expression of TLR9 mRNA in KU812 was determined by quantitative real-time PCR. The results showed that the percentage of TLR9⁺ CCR3⁺ cells in blood granulocytes increased by 46% in patients with AR, but not in peripheral blood mononuclear cells (PBMCs). Allergens namely Dermatophagoide allergen extract (DAE) and Platanus pollen allergen extract (PPAE) upregulated the expression of TLR9 in CCR3⁺ granulocytes by 76% and 84%, respectively. DAE and PPAE also enhanced the proportions of TLR9⁺ CD123⁺ HLA-DR^- cells and TLR9⁺ CCR3⁺ CD123⁺ HLA-DR^- cells in granulocytes and PBMCs of patients with AR. In order to investigate the actions of allergens on basophils, KU812 cells were used. It was observed that all KU812 cells expressed TLR9, and the expression intensity of TLR9 in a single KU812 cell was elevated by CpG. IL-37, IL-31, IL-33, Artemisia sieversiana wild allergen extract (ASWAE), DAE, OVA and Der p 1 induced an increase in the expression of TLR9 mRNA and IL-6 production in KU812 cells. It was shown that the percentage of TLR9-expressing basophils increased in the blood of ovalbumin (OVA)-sensitized mice. In conclusion, an increased expression of TLR9 and the production of IL-6 in basophils implicate that the contribution of basophils to AR is likely via TLR9.

Degradation of bacterial permeability family member A1 (BPIFA1) by house dust mite (HDM) cysteine protease Der p 1 abrogates immune modulator function

Bacterial permeability family member A1 (BPIFA1) is one of the most abundant proteins present in normal airway surface liquid (ASL). It is known to be diminished in asthmatic patients' sputum, which causes airway hyperresponsiveness (AHR). What is currently unclear is how environmental factors, such as allergens' impact on BPIFA1's abundance and functions in the context of allergic asthma. House dust mite (HDM) is a predominant domestic source of aeroallergens. The group of proteases found in HDM is thought to cleave multiple cellular protective mechanisms, and therefore foster the development of allergic asthma. Here, we show that BPIFA1 is cleaved by HDM proteases in a time-, dose-, and temperature-dependent manner. We have also shown the main component in HDM that is responsible for BPIFA1's degradation is Der p1. Fragmented BPIFA1 failed to bind E. coli lipopolysaccharide (LPS), and hence elevated TNFα and IL-6 secretion in human whole blood. BPIFA1 degradation is also observed in vivo in bronchoalveolar fluid (BALF) of mice which are intranasally instilled with HDM. These data suggest that proteases associated with environmental allergens such as HDM cleave BPIFA1 and therefore impair its immune modulator function.

iTRAQ‑based proteomic analysis reveals potential regulatory networks in dust mite‑related asthma treated with subcutaneous allergen immunotherapy

Asthma is one of the most common childhood chronic diseases worldwide. Subcutaneous immunotherapy (SCIT) is commonly used in the treatment of house dust mite (HDM)‑related asthma in children. However, the therapeutic mechanism of SCIT in asthma remains unclear. The present study aimed to investigate the molecular biomarkers associated with HDM‑related asthma in asthmatic children prior and subsequent to SCIT treatment compared with those in healthy children via proteomic analysis. The study included a control group (30 healthy children), ‑Treatment group (30 children with HDM‑related allergic asthma) and +Treatment group (30 children with HDM‑related allergic asthma treated with SCIT). An isobaric labeling with relative and absolute quantification‑based method was used to analyze serum proteome changes to detect differentially expressed proteins, while functional enrichment and protein‑protein interaction network analysis were used to select candidate biomarkers. A total of 72 differentially expressed proteins were detected in the ‑Treatment, +Treatment and control groups. A total of 33 and 57 differentially expressed proteins were observed in the ‑Treatment vs. control and +Treatment vs. control groups, respectively. Through bioinformatics analysis, 5 candidate proteins [keratin 1 (KRT1), apolipoprotein B (APOB), fibronectin 1, antithrombin III (SERPINC1) and α‑1‑antitrypsin (SERPINA1)] were selected for validation by western blotting; among them, 4 proteins (KRT1, APOB, SERPINC1 and SERPINA1) showed robust reproducibility in asthma and control samples. This study illustrated the changes in proteome regulation following SCIT treatment for asthma. The 4 identified proteins may serve as potential biomarkers prior and subsequent to SCIT treatment, and help elucidate the molecular regulation mechanisms of SCIT to treat HDM‑related asthma.

Real-world evidence of subcutaneous allergoid immunotherapy in house dust mite-induced allergic rhinitis and asthma

BACKGROUND

The objective of this study was to analyze the effectiveness of allergen immunotherapy (AIT) with an allergoid in the treatment of house dust mites (HDM)-induced allergic rhinitis and/or asthma based on recent real-life data. The outcomes were measured using asthma incidence and consumption of corresponding medications as the indicator of persisting symptoms.

METHODS

In this retrospective cohort analysis of a German longitudinal prescription database, patients who received at least two relevant mite AIT prescriptions in two different successive seasonal cycles were compared with non-AIT patients who received at least three symptomatic allergic rhinitis (AR) prescriptions in successive mite seasons. Study endpoints included AR progression, asthma progression, asthma occurrence, and therapy adherence. We used multivariate regression analyses to estimate the effects of AIT, adjusting for relevant variables.

RESULTS

This study included 2350 patients receiving a mite allergoid and 64 740 control patients. After up to 6 years of follow-up, patients treated with mite allergoid required significantly fewer AR and asthma prescriptions (59.7% vs 10.8%) than the control group, and the probability of asthma development was significantly lower. The adherence of patients receiving allergoid was 63.8% at the end of the second year and 38.6% at the end of the third year.

CONCLUSIONS

This real-world evidence confirms the good efficacy of subcutaneous AIT with HDM mite allergoid in the treatment of allergic rhinitis and/or asthma. Up to 6 years of follow-up revealed significant effects in allergic rhinitis by measuring the number of AR medications and demonstrating significant reductions in asthma medications.

Haze facilitates sensitization to house dust mites in children

Allergy to house dust mites (HDMs) can cause allergic rhinitis, allergic asthma and allergic skin disorders, which is becoming an enormous worldwide health and economic burden. To explore the relationship between air pollution and HDMs sensitization in children, this study used immunoblotting to determine the concentration of HDM serum-specific IgE (sIgE) in children with allergic diseases in Hangzhou. HDM sIgE was used to reflect the sensitization of children with HDMs. Using the meteorological and atmospheric pollutant data for Hangzhou, a distributed lag nonlinear model was founded to evaluate the effect of atmospheric pollutants on HDMs sensitization. Particulate matter (PM) _2.5 and PM₁₀ were the main air pollutants in Hangzhou. The positive rate of HDM sIgE in children's serum increased with increasing PM_2.5 and PM₁₀ concentrations, and this effect was most obvious on the seventh and tenth days after increased PM_2.5 and PM₁₀ concentrations, respectively. In addition, there was a significant positive correlation between the concentration of HDM sIgE and the total serum IgE concentration. The rate of sensitization to HDMs rose dramatically in the first 3 years after birth. In addition, the period between June and November had the largest number of HDM sIgE-positive patients. Studies have shown that PM_2.5 and PM₁₀ are important factors in HDM sensitization, which presented obvious dose effects and lag effects. Children under the age of 3 years were the most susceptible to HDMs, and the period from June to November had a high risk of dust mite exposure. Avoiding exposure to particulate matter may have benefits in preventing HDM sensitization in children.

Qi-Wei-Du-Qi-Wan and its major constituents exert an anti-asthmatic effect by inhibiting mast cell degranulation

ETHNOPHARMACOLOGICAL RELEVANCE

In Asia, Qi-Wei-Du-Qi-Wan (QWDQW) is a traditional Chinese medicine that has been used to treat chest tightness, cough, shortness of breath, night sweats, frequent urination and asthma. QWDQW is recorded in Yi Zong Yi Ren Pian (Medical Physician's Compilation), which was written by Yang Cheng Liu during the Qing Dynasty.

AIM OF THE STUDY

The traditional Chinese medicine QWDQW is composed of 7 ingredients and has been used in the treatment of asthma in Asia for hundreds of years. However, the mechanism through which QWDQW affects the immune system in the treatment of asthma is not known. Therefore, this study aimed to investigate whether QWDQW alleviates asthmatic symptoms in mice with chronic asthma induced by repeated stimulation with Dermatophagoides pteronyssinus (Der p) and to explore the underlying immune modulatory mechanism.

MATERIALS AND METHODS

BALB/c mice were stimulated intratracheally (i.t.) with Der p (40 μl, 2.5 μg/μl) once weekly for 6 weeks. Thirty minutes prior to Der p stimulation, the mice were treated with QWDQW (0.5 g/kg and 0.17 g/kg) orally. Three days after the last stimulation, the mice were sacrificed, and infiltration of inflammatory cells, lung histological characteristics, gene expression of lung and serum total IgE were assessed. In other experiments, RBL-2H3 cells were stimulated with DNP-IgE/DNP-BSA and then treated with QWDQW, quercetin, β-carotene, luteolin or a mixture of the three chemicals (Mix13) for 30 min, and the effects of the drugs on RBL-2H3 cell degranulation after DNP stimulation were determined.

RESULTS

QWDQW significantly reduced Der p-induced airway hyperreactivity (AHR) and decreased total serum IgE and Der p-specific IgE levels. Histopathological examination showed that QWDQW reduced inflammatory cell infiltration and sputum secretion from goblet cells in the lungs. Gene expression analysis indicated that QWDQW reduced overproduction of IL-12、IFN-γ、IL-13、IL-4、RNATES、Eotaxin and MCP-1in lung. Additionally, QWDQW and Mix13 suppressed DNP induced RBL-2H3 degranulation, and the effect was maximal when quercetin, β-carotene and luteolin were administered together.

CONCLUSION

These results indicate that QWDQW plays a role in suppressing excessive airway reaction and in specific immune modulation in a mouse model of chronic asthma and that QWDQW suppresses mast cell degranulation at defined doses of quercetin, β-carotene and luteolin.

House dust mite-specific immunotherapy alters the natural course of atopic march

Allergen immunotherapy (AIT) is an effective treatment for patients with allergic diseases; it has been shown to modify the underlying cause of the disease. The house dust mite (HDM) is a major perennial allergen source and a significant cause of allergic-related diseases such as allergic rhinitis, asthma, and atopic dermatitis. HDM allergen is an important factor in the pathogenesis of allergic diseases. Sensitization to HDM allergen often occurs early in life and appears to play an important role in the progression from allergic rhinitis to asthma in children. The role of HDM AIT results in immunologic tolerance, provides an alternative option for treating HDM allergy through targeting the mechanisms of allergic reaction, and creates a long-term benefit. There are two forms of testing for aeroallergen, either detect by skin testing or by in vitro IgE assays. Both subcutaneous immunotherapy and sublingual immunotherapy are effective in the treatment of allergic diseases. In the future, new forms of allergen extracts can help improve safety and efficacy of AIT. Novel approaches to immunotherapy currently being explored include the use of adjuvants, allergen-derived peptides, modified recombinant allergen vaccines, and gene-specific immunotherapy.

Dermatophagoides spp. hypoallergens design: what has been achieved so far?

Introduction: Allergic illnesses are one of the most prevalent immunological disorders worldwide and house dust mites are important triggers of these diseases. Allergen-specific immunotherapy (AIT) is an alternative treatment to pharmacotherapy and among its technologies, recombinant hypoallergenic derivatives have shown promising features, turn them into safer and more efficient allergy vaccines.Areas covered: Patents and scientific publications referring to advances in the design of Dermatophagoides spp. hypoallergenic molecules. Data were obtained from the Espacenet® and PubMed websites, using different key terms, advanced tools and Boolean operators for searches. The retrieved data were then descriptively analyzed, taking into consideration clinical targets, geographical, temporal, collaborative, and different classification aspects of the productions.Expert opinion: Joint advances of molecular biology, genetic engineering, and bioinformatics technologies led to progresses in the design of Dermatophagoides spp. hypoallergenic derivatives. Collaborative networks seem to be an interesting way not only to improve technologies in AIT but also to boost the number of patents, publications, and grants for researchers. The observed trend for the use of hypoallergenic hybrid molecules was a fundamental AIT advance and this type of molecule appears to be a more attractive product for companies and more convenient, efficient, and safer allergy immunotherapy for patients.

Real-World Adherence and Evidence of Subcutaneous and Sublingual Immunotherapy in Grass and Tree Pollen-Induced Allergic Rhinitis and Asthma

PURPOSE

Allergen immunotherapy (AIT), when continued for 3 years, is the only disease-modifying treatment for AR and asthma. Adherence is a key to ensure effectiveness, and poor adherence is a contraindication for AIT. The objective of this study was to evaluate real-world adherence to AIT with subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) preparations in patients allergic to grass or tree pollen. The impact of AIT on the consumption of asthma and rhinitis medication was also analyzed.

PATIENTS AND METHODS

In this retrospective cohort analysis of a German longitudinal prescription database, the adherence of a grass and tree pollen allergoid was examined and compared to two sublingual AIT tablets/drops. Patients receiving grass or tree allergen-specific immunotherapy prescriptions were compared with non-AIT patients receiving symptomatic allergic rhinitis (AR) and asthma prescriptions. The study endpoints included therapy adherence, AR progression, and asthma progression. Multivariate regression analyses were used to estimate the effects of SCIT or SLIT, adjusting for variables related to demographics and prescriptions.

RESULTS

SCIT adherence was 60.1-61.8% at 2 years and 35.0-37.5% at 3 years for the two allergens. SLIT adherence was distinctly lower (29.5-36.5% and 9.6-18.2%, respectively). Adherence in children was higher compared to adolescents or adults. All products were highly efficacious at reducing symptomatic AR medication consumption. SCIT also reduced asthma medication use for both allergens, whereas for SLIT these results were significant only for grasses but not trees.

CONCLUSION

Subcutaneous AIT in a real-world setting achieved significantly higher adherence rates compared to sublingual administration. SCIT reduced the use of rhinitis and asthma medication significantly for both allergens, while SLIT reduced the use of rhinitis medication for both allergens and the use of asthma medication for grasses only.

Polyozellin alleviates atopic dermatitis-like inflammatory and pruritic responses in activated keratinocytes and mast cells

Polyozellus multiplex is an edible mushroom that offers beneficial pharmacological effects against intestinal inflammation and cancer. Previous studies have demonstrated that polyozellin, a major component of P. multiplex, has therapeutic activities against inflammation, cancer, and oxidative stress-related disorders. This study aimed to determine the pharmacological effects of polyozellin on inflammatory and pruritic responses, the major symptoms of atopic dermatitis (AD), and to define its underlying mechanism of action. Our results showed that polyozellin inhibited the expression of inflammatory cytokines and chemokines through blockade of signal transducer and activator of transcription 1 and nuclear factor-κB in activated keratinocytes, the major cells involved in AD progression. Based on the histological and immunological analyses, oral treatment with polyozellin attenuated the Dermatophagoides farinae extract (DFE)/2,4-dinitrochlorobenzene (DNCB)-induced atopic inflammatory symptoms in the skin. Pruritus is an unpleasant sensation for AD patients that causes scratching behavior and ultimately exacerbates the severity of AD. To find a possible explanation for the anti-pruritic effects of polyozellin, we investigated its effects on mast cells and mast cell-derived histamines. Oral treatment with polyozellin reduced the DFE/DNCB-induced tissue infiltration of mast cells, the serum histamine levels, and the histaminergic scratching behaviors. Additionally, polyozellin decreased the immunoglobulin E-stimulated degranulation of mast cells. Taken together, the findings of this study provide us with novel insights into the potential pharmacological targets of polyozellin for treating AD by inhibiting the inflammatory and pruritic responses.

Socio-environmental profile of child and adolescents sensitized by house dust mite in northeast of Brazil

INTRODUCTION

The association regarding the atopic sensitization to mite aeroallergens and the socio-environmental features is still inconsistent.

OBJECTIVES

We analyzed the role played by socioeconomic and environmental factors in the prevalence of sensitization to house dust mite (HDM) allergens, and associated with the risk of developing asthma symptoms.

PATIENTS AND METHODS

This is a case-control study conducted with 108 patients, aged 1-17. We inquired about family habits, socioeconomic and environmental features. We applied the International Study of Asthma and Allergies in Childhood questionnaire.

RESULTS

We observed patients sensitized to all HDM tested, Derp (42%), Derf (37%) and Blot (33%). Middle family income (OR: 2.74; CI95%: 1.127-6.684), exposure to dog (OR: 3.758, CI95%: 1.127-6.684) and artificial climatization (OR: 4.319, CI95%: 1.398-13.348) were associated with sensitization to Derp. We also observed protective factors, such as sharing of dormitories, washing cycle for bedspreads and the presence of basic sanitation. An increased risk of sensitization to Derf was associated with Blot sensitization (OR: 3.172, CI95%: 1.083-9.292) and presence of mold on the walls (OR: 3.095, CI95%: 1.063-9.008). A protective factor was dormitory sharing. For sensitization to Blot, we observed an increase in the risk associated with Derp sensitization (OR: 3.462, CI95%: 1.191-10.061) and exposure to dog (OR: 3.255, CI95%: 0.987-10.736). In addition, sensitization to Blot increases the risk of developing asthma symptoms (OR: 2.732, CI95%: 0.981-7.606).

CONCLUSION

Our data show distinct sociodemographic and environmental relations that lead to HDM sensitization and increased probability of development of allergic diseases.

Anti-Atopic Dermatitis Effect of Seaweed Fulvescens Extract via Inhibiting the STAT1 Pathway

Seaweed fulvescens (SF) is a green alga rich in chlorophyll with unique flavor and taste. It is also called Maesaengi which has antioxidant and other physiological activities. In the present study, we evaluated the therapeutic effects of SF in a mouse model of Dermatophagoides farinae body-induced atopic dermatitis (AD) and in tumor necrosis factor-α and interferon-γ-stimulated HaCaT keratinocytes. SF treatment (200 mg/mouse) inhibited the development of AD symptoms, compared to that in the control group, as evidenced from the improved dorsal skin lesion, reduced thickness and infiltration of inflammatory cells and smaller lymph nodes, and reduced levels of proinflammatory cytokines. In HaCaT keratinocytes, SF (10, 25, and 50 μg/mL) suppressed the production of proinflammatory cytokines in a dose-dependent manner. In addition, SF reduced the phosphorylation of signal transducer and activator of transcription 1, which is one of the major signaling molecules involved in cellular inflammation. These results suggested that SF could be a potential therapeutic alternative for the treatment of AD.

Treatment of Allergic Rhinitis as a Strategy for Preventing Asthma

PURPOSE OF REVIEW

To evaluate the impact of allergic rhinitis (AR) on the development of asthma and to update readers on recent literature suggesting that early treatment of allergic subjects with immunotherapy may prevent asthma onset.

RECENT FINDINGS

AR is frequently associated with asthma, leading to the concept that these two conditions are different aspects of the same disease. There is increasing evidence that AR precedes the onset of asthmatic symptoms and current treatment strategies are beneficial in symptom control with no impact prevention. There is limited knowledge about the risk factors responsible for the progression of AR to asthma, though recent data supports the notion that it is possible to prevent asthma onset by allergen immunotherapy. Despite significant advances in specific immunotherapy (SIT) therapy strengthening its efficacy in AR and possible prevention of progression to asthma, the adoption of this therapeutic strategy is still restricted in comparison to therapies directed towards treatment of AR symptoms. Unlike corticosteroids and other symptomatic therapies, the benefit of SIT treatment in allergic individuals has been shown to prevent the development of allergic conditions. Hence, large well-conducted randomized clinical trials with long-term efficacy of SIT are required to confirm or refute the concept that SIT may abrogate the progression of AR to asthma in patients.