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House-dust mites (HDM) allergy is the prevailing condition in subjects allergic to inhalants. Clinical studies with HDM extracts—either subcutaneous (SCIT) or sublingual (SLIT) have long been characterized by small sample size, varying allergen doses, and poorly defined endpoints assessing disease severity. In the last decade, well-designed, randomized, controlled studies recruiting thousands of patients have been conducted with newly developed HDM sublingual tablets (SQ®-HDM tablets). This drug is easily dispersible in the oral cavity due to the patented Zydis® technology and its allergen composition is balanced in terms of group I and group II major mite allergen content, reflecting the equal contribution of the two components to HDM sensitization. HDM is the most common allergen associated with asthma. Clinical efficacy of the SQ® HDM SLIT-tablet in HDM allergic asthma has been evaluated in randomized, double-blind, placebo-controlled trials. Both endpoints related to "present" asthma control (inhaled corticosteroid—ICS) as well as endpoints related to "future" asthma control (occurrence of asthma exacerbations) were included in these studies, in agreement with GINA (Global Initiative for Asthma) guidelines. Based on the positive results of these studies, SQ®-HDM SLIT-tablets were approved Europe-wide as registered drug for treating moderate-to-severe allergic rhinitis with or without allergic asthma and not well controlled HDM allergic asthma, associated with allergic rhinitis of any severity. GINA guidelines in 2017 included SLIT-tablet-based immunotherapy as an "add-on" treatment for asthmatic patients sensitized to HDM; indeed, allergen immunotherapy (AIT) is considered to be a complementary treatment option that targets the immunological of allergic diseases, representing the only treatment potentially disease-modifier or, at least, with a long-term efficacy. The availability of a safe, standardized, registered treatment for HDM respiratory allergies is pivotal in the immunotherapy field, pushing it out of a century-long limbo of amatorial interest towards the full dignity deserved by the only casual treatment of respiratory allergies. [ABSTRACT FROM AUTHOR]

Background MicroRNAs (miRNAs) may facilitate cell-to-cell communication via extracellular vesicles (EVs). The biological roles of miRNAs in EVs on allergic airway inflammation are unclear. Methods Airway-secreted EVs (AEVs) were isolated from bronchoalveolar lavage fluid (BALF) of control and house-dust mite (HDM) allergen-exposed HDM-sensitized mice. The expression of miRNAs in AEVs or miRNAs and mRNAs in lung tissue was analysed using miRNA microarray. Results The amount of AEV increased 8.9-fold in BALF from HDM-exposed mice compared with that from sham-control mice. HDM exposure resulted in significant changes in the expression of 139 miRNAs in EVs and 175 miRNAs in lung tissues, with 54 miRNAs being common in both samples. Expression changes of these 54 miRNAs between miRNAs in AEVs and lung tissues after HDM exposure were inversely correlated. Computational analysis revealed that 31 genes, including IL-13 and IL-5Ra, are putative targets of the miRNAs up-regulated in AEVs but down-regulated in lung tissues after HDM exposure. The amount of AEV in BALF after HDM exposure was diminished by treatment with the sphingomyelinase inhibitor GW4869. The treatment with GW4869 also decreased Th2 cytokines and eosinophil counts in BALFs and reduced eosinophil accumulation in airway walls and mucosa. Conclusion These results indicate that selective sorting of miRNA including Th2 inhibitory miRNAs into AEVs and increase release to the airway after HDM exposure would be involved in the pathogenesis of allergic airway inflammation. [ABSTRACT FROM AUTHOR]

Backgrounds: House-dust mites are the main cause of allergic rhinitis in Asia, for which immunotherapy (SLIT) is a currently accepted treatment. However, few studies have evaluated the efficiency of SLIT on Asian children with allergic rhinitis for a period longer than one year. The aim of this study was to investigate the efficacy and safety of SLIT for Asian children with allergic rhinitis due to house-dust mites over a 2-year period. Materials and Method: This study included 65 patients who had allergic rhinitis due to Dermatophagoides pteronyssinus and Dermatophagoides farinae. All patients were treated with SLIT (StaloralⓇ). Symptom scores and quality of life were evaluated by using questionnaires over two years. The medication score was assessed monthly by a diary medication card and serologic tests were evaluated before and two years after the start of treatment. Adverse effects and dropout rates were also investigated. Results: All nasal and non-nasal symptoms and quality of life were significantly improved after two years of treatment. Furthermore, the total medication score decreased significantly and the serologic tests showed a significant change two years after the start of SLIT. Although minor adverse effects were reported, no systemic reactions were observed. The dropout rate was 40%. Conclusion: SLIT is an efficient and safe therapeutic tool for a period of two years in Asian children with allergic rhinitis to house-dust mites. [ABSTRACT FROM AUTHOR]

Background: The alarmin interleukin 33 (IL-33) and its receptor ST2 play an important role in mucosal barrier tissues, and seem to be crucial for Th2-cell mediated host defense. Galacto-oligosaccharides (GOS), used in infant formulas, exhibit gut and immune modulatory effects. To enhance our understanding of the immunomodulatory capacity of GOS, this study investigated the impact of dietary GOS intervention on IL-33 and ST2 expression related to intestinal barrier dysfunction and asthma. Methods: B6C3F1 and BALB/c mice were fed a control diet with or without 1% GOS. To simulate intestinal barrier dysfunction, B6C3F1 mice received a gavage with the mycotoxin deoxynivalenol (DON). To mimic asthma-like inflammatory airway responses, BALB/c mice were sensitized on day 0 and challenged on days 7-11 with house-dust mite (HDM) allergen. Samples from the intestines and lungs were collected for IL-33 and ST2 analysis by qRT-PCR, immunoblotting and immunohistochemistry. Results: Dietary GOS counteracted the DON-induced IL-33 mRNA expression and changed the IL-33 distribution pattern in the mouse small intestine. The IL-33 mRNA expression was positively correlated to the intestinal permeability. A strong positive correlation was also observed between IL-33 mRNA expression in the lung and the number of bronchoalveolar fluid cells. Reduced levels of IL-33 protein, altered IL-33 distribution and reduced ST2 mRNA expression were observed in the lungs of HDM-allergic mice after GOS intervention. Conclusions: Dietary GOS mitigated IL-33 at the mucosal surfaces in a murine model for intestinal barrier dysfunction and HDM-induced asthma. This promising effect may open up new avenues to use GOS not only as a prebiotic in infant nutrition, but also as a functional ingredient that targets inflammatory processes and allergies associated with IL-33 expression. © 2015 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Introduction: Specific immunotherapy has shown to be very useful for allergy control in dogs, with a common success rate ranging from 65% to 70%. However, this efficacy could probably be improved and the identification of individual allergomes, with the choice of more adequate molecular allergen pools for specific immunotherapy, being the strategy. Aim: To map Dermatophagoides pteronyssinus (Der p) allergens for mite-sensitized atopic dogs, for better understanding how individual allergograms may influence the response to house-dust mite immunotherapy. Material and methods: To identify the Der p mite allergome for dogs, 20 individuals allergic to dust-mites and sensitized to Der p, were selected. The extract from Der p was submitted to isoelectric focusing (IEF), one-dimensional (1-D) and two-dimensional (2-D) sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Separated proteins were blotted onto polyvinylidene difluoride (PVDF) membranes and immunoblottings were performed with patient sera. Allergen-bound specific IgE was detected. Results: Eleven allergens were identified from isoelectric focusing (IEF), as well as from 1-D SDS PAGE. From 2-D SDS-PAGE, 24 spots were identified. Conclusions: Several similarities were found between dog and human allergograms and no absolute correlation between sensitization and allergy was observed either. As in humans, different individual allergograms do not seem to implicate different clinical patterns, but may influence the response to specific immunotherapy. The molecular epidemiology approach in veterinary allergy management, by the characterization of individual patients' allergoms and by choosing the best molecular allergen pool for each patient could also improve the efficacy of allergy immunotherapy. [ABSTRACT FROM AUTHOR]

Abstract: Lactobacillus plantarum CJLP133 was isolated from Kimchi, a Korean fermented food, and its potential to improve mouse atopic dermatitis after onset was studied. Dermatitis was developed through house dust-mite extract application onto NC/Nga mice, and then CJLP133 feeding was started. CJLP133 suppressed dermatitis-like skin lesions and decreased high serum IgE levels through balancing between IL-4 and IFN-γ in serum. CJLP133 diminished skin thickening, mast cell accumulation into inflamed site, and lymph node enlargement. In lymph node cells, CJLP133 repressed secretion of T cell cytokines such as IFN-γ, IL-4, IL-5, and IL-10. However, CJLP133 decreased ratios of IFN-γ and IL-5 to IL-10 in lymph node cells, while it did not decrease ratios of IL-4 and IL-5 to IFN-γ. Conclusively, CJLP133 exhibited therapeutic potential for atopic dermatitis in mice through orderly increment of type 1 helper T cell activation and regulatory T cell activation. These results suggest that CJLP133 could treat human atopic dermatitis. [Copyright &y& Elsevier]

Introduction: Cutaneous test practice to identify atopy is recommended in persons who suffer persistent asthma. Objective: To estimate the prevalence of allergen sensitization in a group of adult asthma patients; plus, to investigate about the differences that exist between atopic and non-atopic asthmatic persons. Methods: Consecutive asthmatic outpatients were evaluated for the first time in an Allergology Service. They were analyzed through clinical history, physical examination, and allergic cutaneous reactivity to any of 38-allergen panel. IgE serum levels were quantified too. Results: One hundred eighty one asthmatic patients were included. Mean age was 40 years; 75.1% were women; in 59.9%, asthma was accompanied by allergic rhinitis; 81.2% fulfilled the atopy criteria. On average, each patient had 7.2 positive skin tests, corresponding to house-dust mite the highest frequency, followed by cockroach. Subjects age correlated negatively with the amount of positive cutaneous test and IgE serum levels, and positively with severity of asthma. IgE serum level higher than 100UI/ml was identified as a predictive factor for atopic asthma (OR = 3.1, p = 0.03). Conclusions: A substancial amount of asthmatic patients were atopic. The most highly sensitizing allergens were house-dust mite and cockroach. Differences between atopic and non-atopic asthmatics depended on their age and IgE serum levels. [ABSTRACT FROM AUTHOR]

Atopic dermatitis (AD) is marked by elevated levels of immunoglobulin E and skin lesions such as oedema and haemorrhage. Kimchi is a Korean fermented food that contains beneficial bacteria for human health. In this study, Lactobacillus plantarum CJLP55, CJLP56, CJLP133 and CJLP136 isolated from Kimchi were investigated for their capacity to inhibit AD. The three strains, CJLP55, CJLP133 and CJLP136, suppressed AD-like skin lesions, high serum IgE levels and epidermal thickening. The three strains diminished the accumulation of eosinophils and mast cells into topical inflammatory sites and the enlargement of axillary lymph nodes, which are responsible for the dorsal dermatitis. CJLP55, CJLP133 and CJLP136 decreased production of type 2 cytokines such as IL-4 and IL-5 in lymph node cell culture. CJLP133 and CJLP136 increased IFN-γ secretion, while CJLP55 enhanced IL-10 production. The three strains isolated from Kimchi suppress house-dust mite-induced dermatitis in NC/Nga mouse, a representative animal model of human AD. These findings suggest that lactobacilli isolated from Kimchi inhibit AD, probably by altering the balance of Th1/Th2 ratio or inducing IL-10 production. [ABSTRACT FROM AUTHOR]

Background: The precise mechanism of specific immunotherapy (SIT), long used for treating allergic diseases, remains undefined. SIT was shown to act by modifying the immune response of T lymphocytes to antigens. We examined the effect of SIT on the expression and use V-alpha, -beta, -gamma and -delta chains of T-cell receptors (TCR) in patients allergic to house-dust mite. Methods: Peripheral venous blood was taken for lymphocyte TCR analysis from 10 house-dust mite (HDM) allergic adults before initiating SIT and 6 months after initiating the treatment. Twelve similarly allergic patients without SIT served as controls. TCR chains were identified by fluorescence-activated cell sorter (FACS) using the following monoclonal antibodies: CD3, CD14, CD8, pan alpha-beta, pan gamma-delta, V-alpha2, V-alpha12.1, V-beta5a, V-beta5b, V-beta5c, V-beta8a, V-beta8b, V-beta3.1, V-beta13, V-beta12, V-beta6.7, V-delta1, V-delta2, V-gamma9, and V-gamma4. Results: Analyzed before and 6 months after SIT initiation, lymphocyte TCR showed significantly increased V-beta5b, V-beta12 and V-alpha12.1 values compared to controls (without significant changes in other markers). Conclusions: SIT caused selective expansion of certain V-beta- and V-alpha-expressing T cells in patients allergic to HDM. Our results support the notion that the effect of SIT in patients with allergic rhinitis may be achieved by modifying the T lymphocyte response through the modulation of TCR usage. [ABSTRACT FROM AUTHOR]

Background: Limpet is a mollusc that is frequently found along the shores of warm seas. Few allergic reactions to limpet have been described, and cross-reactivity with house-dust mites has not been established. Methods: We report five patients with anaphylactic reactions due to limpet ingestion. A limpet extract was prepared and skin prick tests (SPT), radioallergosorbent assays (RAST), sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE), and IgE-immunoblotting were performed. In order to evaluate cross-reactivity, an immunoblotting inhibition assay with Dermatophagoides pteronyssinus was also done. Results: All patients were asthmatics sensitized to house-dust mites. In each case, severe bronchospasm was evidenced, and three required mechanical ventilation. Positive SPT with limpet extract was found in the four patients tested. RAST showed specific IgE on each patient's sera. Immunoblotting showed several allergenic fractions with a wide molecular weight range (15–250 kDa). D. pteronyssinus inhibited IgE-binding molecules above 50 kDa in the limpet extract, particularly one molecule of 75 kDa. Conclusions: We describe five patients with IgE-mediated limpet allergy. Severe bronchospasm was the most important symptom. Cross-reactivity with D. pteronyssinus was demonstrated. [ABSTRACT FROM AUTHOR]

Background: HDM distribution varies between geographic areas and may be affected by housing characteristics. We quantified Der p 1 and Der f 1 and assessed the relationships between their levels and housing characteristics in homes of nonallergic subjects. Methods: Der f 1 and Der p 1 were measured by ELISA in dust samples from living-room floors and mattresses of 44 homes of nonallergic subjects in Pavia. Information about household characteristics was obtained by questionnaire. Results: Der p 1 and Der f 1 concentrations (μg/g dust, median) were 0.34 and 7.8 on mattresses, and 0.15 and 0.83 on living-room floors. Higher Der f 1 levels on mattresses were associated with synthetic pillows (P<0.05), and (only when expressed as μg/m2) with bedding washing temperature of ≤60°C (P<0.05). Der f 1 levels were higher on the living-room floors of homes located on lower (≤first) floors (P<0.05). Good correlations were found between Der p 1 and Der f 1 expressed as μg/g dust and μg/m2 on both mattresses and living-room floors. Conclusions: In homes of nonallergic subjects in northern Italy, Der f 1 exceeded the threshold for sensitization in a high proportion of mattress samples. [ABSTRACT FROM AUTHOR]

Background: The safety and efficacy of sublingual-swallow immunotherapy (SLIT) in rhinitis caused by house-dust mite were evaluated in a double-blind, placebo-controlled study including 75 patients for 24 months. Methods: Patients received either placebo or SLIT with a standardized Dermatophagoides pteronyssinus (D.pt.) – D. farinae (D.f.) 50/50 extract. The mean cumulative dose was 90 000 IR, equivalent to 2.2 mg of Der p 1 and 1.7 mg of Der f I. Symptom and medication scores were assessed throughout the study. Exposure to house-dust mite, skin sensitivity, and serum specific IgE and IgG4 were assessed before starting treatment and after 12 and 24 months. Results: Seventy-two patients (36 active–36 placebo) were eligible for intent-to-treat analysis. Thirty-six patients dropped out of the study. The number of patients who dropped out due to lack of efficacy was eight out of 37 (21.6%) in the active treatment group compared to 15 out of 38 (39.5%) in the placebo group (chi-square=2.81, P=0.09). Total symptom and medication scores decreased significantly after 12 and 24 months (P<0.05) of treatment in both groups, but no significant difference was observed between the active and placebo groups. After 24 months, the number of patients with high levels of indoor allergenic load decreased significantly in both groups compared to baseline data (P=0.01). Specific IgE (D.pt. and D.f.) increased significantly in the active treatment group after 12 and 24 months, while no change was observed in the placebo group. Specific IgG4 levels were not significantly modified in either group. Two patients in each group reported mild adverse effects. No severe adverse effects were reported. Conclusions: We conclude that SLIT in rhinitis caused by house-dust mite was safe, but there was a lack of consistent clinical benefit compared to placebo, probably due to the impact of the allergen avoidance measures that lowered the allergen burden. [ABSTRACT FROM AUTHOR]

A double‐blind, placebo‐controlled study was carried out in 85 patients with a well‐documented history of perennial asthma caused by house‐dust mites. Patients received either placebo or sublingual immunotherapy (SLIT) with a standardized Dermatophagoides pteronyssinus (DP)–D. farinae (DF) 50/50 extract. After a run‐in period, patients received increasing doses up to 300 IR every day for 4 weeks and then three times a week for the following 24 months. The cumulative dose was about 104 000 IR, equivalent to 4.2 mg Der p 1 and 7.3 mg Der f 1. Symptom and medication scores and respiratory function were assessed throughout the trial. Serum specific IgE and IgG4 were determined before SLIT (t0) and after 6 (t1), 11 (t2), 17 (t3), and 25 months (t4) of SLIT. Mite exposure was evaluated at t0, t2, and t4 by semiquantitative guanine determinations. Patients aged 15 years and older were asked to assess their quality of life (QoL) by completing the SF20 (Short Form Health Status Survey) plus two items at t0, t2, and t4. Use of inhaled corticosteroids and β2‐agonists was significantly decreased after 25 months of treatment in both groups (P<0.03). SLIT patients showed significant improvements in respiratory function at t4 (% predicted FEV1 (P=0.01), VC (P=0.002), morning (P=0.01) and evening (P=0.03) PEFR), and reduction in daytime asthma score (P=0.02). In the SLIT group, the post‐treatment PD20 was 1.75 times higher than the baseline value. There was no change in PD20 in the placebo group. Compared to the placebo group, the SLIT group showed a significant increase in specific IgE DP (P=0.05), IgE DF (P=0.02), IgG4 DP (P=0.001), and IgG4 DF (P=0.001) levels after SLIT. QoL scores were similar in both groups at t0 and... [ABSTRACT FROM AUTHOR]

Summary Infants have a higher risk of developing allergic asthma than adults. However, the underlying mechanism remains unknown. We show here that sensitization of mice with house-dust mites (HDMs) in the presence of low-dose lipopolysaccharide (LPS) prevented T helper 2 (Th2) cell allergic responses in adult, but not infant, mice. Mechanistically, adult CD11b+ migratory dendritic cells (mDCs) upregulated the transcription factor T-bet in response to tumor necrosis factor-α (TNF-α), which was rapidly induced after HDM + LPS sensitization. Consequently, adult CD11b+ mDCs produced interleukin-12 (IL-12), which prevented Th2 cell development by promoting T-bet upregulation in responding T cells. Conversely, infants failed to induce TNF-α after HDM + LPS sensitization. Therefore, CD11b+ mDCs failed to upregulate T-bet and did not secrete IL-12 and Th2 cell responses normally developed in infant mice. Thus, the availability of TNF-α dictates the ability of CD11b+ mDCs to suppress allergic Th2-cell responses upon dose-dependent endotoxin sensitization and is a key mediator governing susceptibility to allergic airway inflammation in infant mice. Graphical Abstract Highlights • Infant mice require high doses of LPS to suppress Th2-driven allergic asthma to HDMs • T-bet+ lung CD11b+ DCs inhibit Th2 cell development after HDM + LPS sensitization • T-bet expression on CD11b+ DCs depends on TNF-α production and TNFR signaling • Infants have an impaired ability to induce TNF-α and T-bet+CD11b+ DCs in response to LPS Children have a higher risk of developing asthma in low-LPS "clean" environments than adults. Bachus et al. demonstrate that infant mice require higher doses of LPS than adult mice to prevent Th2-dependent allergic responses because of the decreased ability to induce LPS-driven TNF-α production and TNFR-mediated CD11b+ dendritic cell activation for Th2 cell suppression. [ABSTRACT FROM AUTHOR]

Focuses on the removal of house-dust mites during laundering of bedding. Influence of temperature on the survival of mites; Procedures for the removal of mites.

Evaluates whether specific immunotherapy against Der p can induce skin prick test positivity to snail extracts in atopic children. Increase in immunoglobulin E antibody level; Symptomatology; Factors influencing snail sensitization.

Evaluates the efficacy of a microfiber fabric as a barrier to indoor allergens. Reduction of sensitization rate to house-dust mites; Assessment of dust quality; Levels of indoor allergen exposure.

Investigates the effect of sieving dust before analysis on concentration of Der p 1, a major group 1 allergen associated with the development of atopic asthma. Recommendation for standardized dust collection techniques; Results of Der p 1 levels from several dust samples; Comparison of Der p 1 concentrations of unsieved and sieved dust samples.