Dermatophagoides Pteronyssinus Extract Research Articles

Pulmonary adaptation to repeated poly(I:C) exposure is impaired in asthmatic mice: an observational study

BackgroundWhile asthma exacerbations remain a major challenge in patient management, few animal models exist to explore the underlying mechanisms. Here, we established an animal model of asthma that can be used to study pathophysiological mechanisms and therapeutic strategies on asthma exacerbation.MethodsFemale BALB/c mice were sensitized and exposed to PBS or Dermatophagoides pteronyssinus (DerP) extract for 11 weeks. Asthmatic phenotype was assessed through lung inflammation, bronchial hyperresponsiveness and bronchial smooth muscle remodeling. Asthmatic and control mice were exposed once or three times to poly(I:C) to simulate virus-induced inflammation.ResultsFourteen days after exposure to DerP, asthmatic mice showed resolution of inflammation with sustained bronchial hyperresponsiveness and bronchial smooth muscle remodeling compared to control. At this stage, when mice were subjected to a single exposure to poly(I:C), control and asthmatic mice were characterized by a significant increase in neutrophilic inflammation and bronchial hyperresponsiveness. When mice were repeatedly exposed to poly(I:C), control mice showed a significant decrease in neutrophilic inflammation and bronchial hyperresponsiveness, while asthmatic mice experienced worsening of these outcomes.ConclusionsThis observational study report an asthmatic mouse model that can undergo exacerbation after repeated exposure to poly(I:C). Our findings on pulmonary adaptation in control mice may also pave the way for further research into the mechanism of adaptation that may be impaired in asthma and raise the question of whether asthma exacerbation may be a loss of adaptation.

Evaluation of Scoring Atopic Dermatitis (SCORAD) and scratching behavior in BALB/c mice treated with house dust mite immunotherapy

Allergen specific immunotherapy controls the reaction and builds immunological tolerance by giving an allergen in escalating doses. Research on immunotherapy in atopic dermatitis (AD) mouse model offers a new perspective on the approach of treatment in AD. This was an experimental study of 33 male BALB/c mice, 6-8 weeks old, divided into 3 groups (control, AD model, and house dust mite/HDM immunotherapy). The mice received spray and patch containing allergen extract of Dermatophagoides pteronyssinus. Immunotherapy was injected subcutaneously in increasing doses. The evaluation of SCORAD and scratching behavior were observed at the end of the treatment on day 93. The SCORAD of the model group that received HDM allergen had a mean of 1.27 ± 0.467 and the immunotherapy group had a mean of 0.36 ± 0.505. There were significant differences between the groups. The model group had a mean of 5.18 ± 4.119 and the immunotherapy group had mean of 1.55 ± 1.293. The statistical analysis showed that there were significant differences between control group and model group, as well as model group and immunotherapy group. Interobserver agreement was assessed and showed substantial agreement for SCORAD (ĸ = 0.613 and p < 0.001) and scratching evaluation (ĸ = 0.714 and p < 0.001). House dust mite immunotherapy significantly reduced SCORAD and scratching behavior in BALB/c mice compared to placebo groups.

Efficacy and Safety of Sublingual Immunotherapy using a Combination of Dermatophagoides Pteronyssinus and Blomia Tropicalis Extracts in Patients with Allergic Rhinitis: A Randomized, Double-Blind, Placebo-Controlled Trial

The aim of this study was to evaluate the safety and efficacy of sublingual immunotherapy (SLIT) with extracts of Dermatophagoides pteronyssinus and Blomia tropicalis in patients with moderate/severe persistent allergic rhinitis (AR). Methods: This was a double-blind, randomized, placebo-controlled trial of SLIT for the treatment of house dust mite-induced AR. A total of 65 patients, aged between 12 and 60 years, were treated for 12 months and randomized into two groups: SLIT and placebo. The SLIT group received a combination of extracts containing Dermatophagoides pteronyssinus and Blomia tropicalis allergens. All had their sensitization confirmed by skin prick test or serum-specific IgE. Total Nasal Symptom Score, RQLQ quality of life questionnaire, current treatment, and need for medication to control symptoms were recorded during the study. Total serum IgE, serum specific IgE, and IgG4 levels to Der p 1 and Blo t were assessed at baseline, 6 and 12 months after treatment. Results: There was no significant difference in the number of adverse events between groups. The SLIT group showed a significant reduction in the consumption of antihistamines to control symptoms (p < 0.0001) when compared to placebo. There was no significant change in serum total IgE, serum specific IgE, and IgG4 to both allergens when comparing the SLIT and placebo groups. Conclusion: After one year, SLIT using a dose of 1 mcg of Der p 1/day and 753 UBE of Blo t/day proved to be effective and safe in controlling AR exacerbations.

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.

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. 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. 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. 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.

NOX2-Deficient Pulmonary Neutrophils and Macrophages Have Lower PD-L1 Expression and May Aggravate Allergic Lung Inflammation through Affecting ILC Populations

Abstract Redox balance plays an important role in the pathogenesis of allergic asthma. We previously reported that NADPH oxidase 2 (NOX2)-derived ROS may modulate tissue inflammation through affecting neutrophil programmed cell death 1 ligand 1 (PD-L1) expression. To reveal the role of NOX2 in regulating PD-L1 expressions on pulmonary neutrophils and macrophages and in ILC differentiation, we established an allergic asthma model using NOX2-deficient (Cybb−/−)mice stimulated with the Dermatophagoides pteronyssinus(Der p) extract along with LPS. We first found that NOX2 deficiency led to increased group 2 innate lymphoid cell (ILC2) in Der p extract induced lung inflammation. The cell numbers of neutrophil, eosinophil and alveolar macrophage (AM) also increased in the stimulated Cybb−/−mice when compared with WT mice. The AM in Cybb−/−mice expressed higher levels of CD11b and the M2 marker CD163 and produced more TNF-α. Moreover, the Cybb−/−neutrophils and AMs had low PD-L1 expressions while ILC2s had significant levels of programmed cell death 1 (PD-1) expression in the inflammatory lungs. Altogether, these results indicated that NOX2 deficiency may lead to downregulation of PD-L1 expression on neutrophils and AMs while eliciting the M2 phenotype and inducing higher amounts of pro-inflammatory cytokine production. Our results suggested that the lowered PDL1 on NOX2-deficient neutrophils and AMs may aggravate allergic Inflammation through affecting ILC populations in the lung.

Evaluating Non-IgE-Mediated Allergens’ Immunoreactivity in Patients Formerly Classified as “Intrinsic” Asthmatics with Help of the Leukocyte Adherence Inhibition Test

Background: The ancient concept of “intrinsic” and “extrinsic” asthma has evolved in line with growing scientific knowledge and the use of new clinical diagnostic tools. Objective: The present study aims to evaluate the non-IgE-mediated immunoreactivity against common allergens, in asthmatic patients without evidence of IgE-mediated hypersensitivity against these allergens. Methods: A group of 127 “intrinsic” asthmatic outpatients, were submitted to ex vivo Leukocyte Adherence Inhibition Tests (LAIT) with extracts of Dermatophagoides pteronyssinus, Hevea brasiliensis latex, dog dander, cat dander, cow’s milk proteins, beekeeping pollen and a mixture of fungal extracts. Results: Cascade graphs were assembled according to the distribution of the LAIT results among the range of results of Leukocyte Adherence Inhibition (LAI) inside each group. A column graph was plotted with the mean LAI results for each antigen. The non-parametric Wilcoxon-Mann-Whitney U-test performed between the results of each test was significant only between the results of the LAIT performed with the dog extract and the mixed fungal extract (U = 1,179.5; the z-score was -2.64109; the p-value was 0.0083). All other Wilcoxon-Mann-Whitney U-test calculations between LAIT performed with the other allergens were not significant at p < 0.01. Conclusion: The evidence of non-IgE-mediated immunoreactivity in allergic patients has been reported in the medical literature since the beginning of the 19th century and has been increasing since then. This descriptive article presents the contribution of the LAIT as a tool to quantify the overall non-IgE-mediated cellular/humoral immunoreactivity against common allergens in patients formerly classified inside the “intrinsic” asthma endotype.

Evaluating Non-IgE-mediated Allergens’ Immunoreactivity in Patients with “Intrinsic” Persistent Rhinitis with Help of the Leukocyte Adherence Inhibition Test

Background: The non-IgE-mediated immunoreactivities against common allergens are little understood conditions, especially in patients suffering from allergic respiratory disorders such as persistent rhinitis. Objective: The present study aims to evaluate the non-IgE-mediated immunoreactivity against common allergens, in allergen-reactive patients clinically diagnosed with persistent rhinitis without evidence of IgE-mediated hypersensitivity against these allergens. Methods: A group of 533 outpatients diagnosed with non-IgE-mediated allergen-reactive persistent rhinitis, were submitted to ex vivo Leukocyte Adherence Inhibition Tests (LAIT) with extracts of Dermatophagoides pteronyssinus, Hevea brasiliensis latex, dog dander, cat dander, cow’s milk proteins, beekeeping pollen and a mixture of airborne fungal extracts. Results: Cascade distribution column graphs were assembled according to the LAIT results among six ranges of Leukocyte Adherence Inhibition (LAI) of each allergen group. A column graph was plotted with the mean LAI results for each antigen for comparison. Conclusion: The LAIT is a potential tool to quantify the overall non-IgE-mediated cellular/humoral immunoreactivity against common allergens in patients clinically diagnosed with persistent rhinitis. Most studies must be done to evaluate the potential of the LAIT as a screening ex vivo provocation test to select the more reactive allergens to perform the diagnostic in vivo provocation tests.

Diagnostic accuracy and safety of Dermatophagoides pteronyssinus extracts used for skin prick test.

Dermatophagoides pteronyssinus is a common allergen causing allergic diseases in China. The aim of this study was to evaluate the efficacy and safety of D. pteronyssinus extracts produced by Peking Union Medical College Hospital (PUMCH) for the skin prick test (SPT) in the diagnosis of D. pteronyssinus allergy. A total of 910 subjects with allergic diseases were prescribed D. pteronyssinus SPT and specific sIgE (sIgE) test among the Outpatients of Department of Allergy, PUMCH from August 10, 2015 to August 30, 2017. Receiver operating characteristic curve (ROC) analysis was performed according to the results of D. pteronyssinus-sIgE detection. The accuracy of D. pteronyssinus extracts used for SPT in the diagnosis of D. pteronyssinus allergy was evaluated under different cutoff values. Adverse events after SPT were recorded to evaluate safety. There were 796 and 618 subjects in the full analysis set (FAS) and the per protocol set (PPS), respectively. The areas under the curve of FAS and PPS were 0.871 and 0.873, respectively. According to the ROC of PPS, the optimal and 95% specificity diagnostic cutoff values of D. pteronyssinus SPT mean wheal diameter were 3.25 and 3.75 mm, respectively. No adverse events occurred. The extracts of D. pteronyssinus for SPT were simple, highly accurate, and safe and should be considered for recommendation in the clinical diagnosis of D. pteronyssinus allergy.

Efficacy and safety of subcutaneous immunotherapy with a mixture of glutaraldehyde-modified extracts of Dermatophagoides pteronyssinus, Dermatophagoides farinae, and Blomia tropicalis

BackgroundAllergen Immunotherapy (AIT) is an effective treatment of allergic respiratory diseases induced by the inhalation of house dust mite allergens. ObjectivesTo evaluate the efficacy and safety of glutaraldehyde polymerized allergen extracts using a mixture of Dermatophagoides pteronyssinus, D. farinae and Blomia tropicalis in mite allergic individuals residing in Colombia. MethodsTwo hundred and fifty (250) patients with allergic rhinoconjunctivitis with, or without asthma and sensitized to D. pteronyssinus, D. farinae and B. tropicalis were included. A glutaraldehyde-modified extract containing a mixture of D. pteronyssinus, D. farinae and B. tropicalis was employed, using a cluster up-dosing schedule followed by a monthly maintenance dose. The primary endpoints to evaluate the clinical impact were the Combined Symptom and Medication Scores (CSMS) for allergic rhinitis, the Asthma Control Test (ACT) and the reduction in medication consumption. ResultsSignificant improvement was found after 3 months of treatment regarding CSMS (p < 0.0001) and ACT (p < 0.0001). Additionally, a significant decrease in medication consumption was found after 3 months of treatment (p < 0.0001). Adverse reactions, either local or systemic were mild and no severe reactions related to the vaccines were observed. ConclusionAfter 12 months of allergen immunotherapy, glutaraldehyde-modified mixture of D. pteronyssinus, D. farinae and B. tropicalis proved to be safe and effective in the treatment of patients with rhinoconjunctivitis with or without asthma due to allergy to mites.

Effect of Dermatophagoides pteronyssinus extract on the expression of genes involved in inflammation and tissue remodeling by peripheral blood mononuclear cells of allergic asthma patients

PurposeHouse dust mite allergy constitutes a risk factor for asthma development and is associated with a faster decline of lung function in allergic asthmatics (AAs).To evaluate the effect of Dermatophagoides pteronyssinus (Dp) allergens on the expression of genes involved in inflammation and tissue remodeling by peripheral blood mononuclear cells (PBMCs) isolated from the blood of AAs. Materials and methodsThe cells from AAs, allergic rhinitis without asthma patients (ARs), and healthy controls (HCs) were cultured in the presence of Dp, lipopolysaccharide (LPS), or without any stimulation. The expression of 84 genes was evaluated using a low-density microarray whereas, the quantitative expression analysis of selected genes was performed using a real-time polymerase chain reaction. The concentration of selected proteins in the cell culture supernatants was assessed using ELISA. ResultsStimulation of PBMCs with Dp and LPS resulted in a significant upregulation of 8 and 15 among 84 studied genes, respectively. The greatest upregulation was observed for CCL2 and CCL3 using Dp and LPS, respectively. In comparison with HCs, in AAs, significantly increased upregulation of CCL2 in response to Dp was found. The secretion of CCL2 and CCL3 by PBMCs reflected the pattern of gene expression at the mRNA level. The mean Dp-stimulated secretion of CCL2 by PBMCs of ARs was less than in AAs (p ​< ​0.01), both being notably greater than in the HCs (p ​< ​0.01). ConclusionRapid and potent upregulation of CCL2 expression by PBMCs in response to Dp may constitute an important contribution to the development of allergic asthma.

Association of heat shock protein 8 with atopic march in a murine experimental model.

BackgroundAtopic march (AM), a unique characteristic of allergic diseases, refers to the sequential progression of atopic dermatitis (AD) in infants to allergic asthma and allergic rhinitis in children and young adults, respectively. Although there are several studies on AM, the establishment of an AM murine model to expand our understanding of the underlying mechanism and to identify the potential biomarkers is yet to be achieved. In this study, an improved murine model was established by applying a method to minimize skin irritation in inducing AD, and it was used to perform integrated analyses to discover candidate biomarkers.MethodsTo induce atopic dermatitis, 2,4-dinitrochlorobenzene (DNCB) was applied to the ear skin once a week, and this was continued for 5 weeks. From the second application of DNCB, Dermatophagoides pteronyssinus (Dp) extract was applied topically 2 days after each DNCB application; this was continued for 4 weeks. Dp sensitization and intranasal challenges were then performed for 4 weeks to develop conditions mimicking AM.ResultsExacerbated airway inflammation and allergic responses observed in the AM-induced group suggested successful AM development in our model. Two-dimensional gel electrophoresis (2-DE) and mass spectrometry analysis identified 753 candidate proteins from 124 2-DE spots differentially expressed among the experimental groups. Functional analyses, such as Gene Ontology (GO) annotation and protein–protein interaction (PPI) analysis were conducted to investigate the relationship among the candidate proteins. Seventy-two GO terms were significant between the two groups; heat shock protein 8 (Hspa8) was found to be included in six of the top 10 GO terms. Hspa8 scored high on the PPI parameters as well.ConclusionWe established an improved murine model for AM and proposed Hspa8 as a candidate biomarker for AM.

Correlation between sensitization to house dust mite major allergens, age, and symptoms in Japanese house dust mite allergic subjects

Der p 23 has recently been recognized as a new house dust mite (HDM) major allergen that may be linked to the development of asthma in HDM allergic patients. This study aimed to investigate the frequency of sensitization to HDM major allergen components including Der p 23 and to examine the correlation between HDM-sensitization and AR symptom score in Japanese HDM allergic rhinitis (AR) patients without allergic asthma.Serum samples (n = 120) collected from Japanese HDM AR patients (12 to 64 years) without asthma were assessed for allergen-specific IgE (s-IgE) by ImmunoCAP (Dermatophagoides pteronyssinus (D. pteronyssinus; Der p) extract, Der p 23) or immunosolid-phase allergen chip (Der p 1, Der p 2).Japanese HDM AR patients without asthma showed a high prevalence of allergic sensitization to the HDM major allergens Der p 1 (94.2%), Der p 2 (97.5%) and Der p 23 (71.7%). No difference in the prevalence was detected for Der p 1 and Der p 2 s-IgE among three age groups. However, the prevalence of Der p 23 s-IgE was significantly higher in the younger group compared to the elderly group. No significant correlation was found between AR symptom scores and concentration of s-IgE towards Der p extract and any of the three HDM major allergens.Although the prevalence of sensitization towards D. pteronyssinus major allergens is high in Japanese AR patients without asthma, there was no correlation between allergen specific IgE including IgE towards Der p 23 and AR symptom in this population.

Efficacy of House Dust Mite Sublingual Immunotherapy in Patients with Atopic Dermatitis: A Randomized, Double-Blind, Placebo-Controlled Trial

Sensitization to house dust mites (HDMs) is frequent in patients with atopic dermatitis. To investigate the efficacy of sublingual immunotherapy (SLIT) with Dermatophagoides pteronyssinus extract in patients with atopic dermatitis sensitized to HDM. In this randomized, double-blind, placebo-controlled trial, we enrolled 91 patients 3 years or older, with SCORing Atopic Dermatitis (SCORAD) score greater than or equal to 15 and positive skin test result and/or IgE to D pteronyssinus. Patients were stratified according to age (<12 and ≥12 years) to receive HDM SLIT or placebo for 18 months. Primary outcome was a greater than or equal to 15-point decrease in SCORAD score. Secondary outcomes were decreases in SCORAD and objective SCORAD, Eczema Area and Severity Index, visual analog scale for symptoms, and pruritus scale scores; Investigator's Global Assessment 0/1; and decrease greater than or equal to 4 points in Dermatology Life Quality Index. Background therapy was maintained. A total of 66 patients completed the study (35 HDM SLIT, 31 placebo). After 18 months, 74.2% and 58% of patients in the HDM SLIT group and the placebo group, respectively, showed greater than or equal to 15-point decrease in SCORAD score (relative risk, 1.28; 95% CI, 0.89-1.83). Significant SCORAD score decreases from baseline of 55.6% and 34.5% in HDM SLIT and placebo groups (mean difference, 20.4; 95% CI, 3.89-37.3), significant objective SCORAD score decreases of 56.8% and 34.9% in HDM SLIT and placebo groups (mean difference, 21.3; 95% CI, 0.66-41.81), and more patients with Investigator's Global Assessment 0/1 in the HDM SLIT group as compared with the placebo group (14 of 35 vs 5 of 31; relative risk, 2.63; 95% CI, 1.09-6.39) were observed at 18 months. Our results suggest that HDM SLIT may be effective in HDM-sensitized patients as an add-on treatment for atopic dermatitis.

Alterations of lung microbial communities in obese allergic asthma and metabolic potential.

In recent years, there has been a rapid increase in microbiome studies to explore microbial alterations causing disease status and unveil disease pathogenesis derived from microbiome environmental modifications. Convincing evidence of lung microbial changes involving asthma has been collected; however, whether lung microbial changes under obesity leads to severe asthma in a state of allergen exposure has not been studied sufficiently. Here, we measured bacterial alterations in the lung of an allergen mouse model induced by a high fat diet (HFD) by using 16S rRNA gene sequencing. A total of 33 pathogen‑free 3‑week‑old male C57BL/6 mice were used, and they divided randomly into two groups. The Chow diet (n = 16) and high fat diet (n = 17) was administrated for 70 days. Mice were sensitized with PBS or Dermatophagoides pteronyssinus extract (Der.p), and concentration levels of total IgE and Der.p-IgE in the blood were measured to quantify immune responses. Although there were no meaningful differences in bacterial species richness in the HFD mouse group, momentous changes of bacterial diversity in the HFD mouse group were identified after the mouse group was exposed to allergens. At a genus level, the fluctuations of taxonomic relative abundances in several bacteria such as Ralstonia, Lactobacillus, Bradyrhizobium, Gaiella, PAC001932_g, Pseudolabrys, and Staphylococcus were conspicuously observed in the HFD mouse group exposed to allergens. Also, we predicted metabolic signatures occurring under microbial alterations in the Chow group versus the Chow group exposed to allergens, as well as in the HFD mouse group versus the HFD group exposed to allergens. We then compared their similarities and differences. Metabolic functions associated with macrophages such as propanoate metabolism, butanoate metabolism, and glycine-serine-threonine metabolism were identified in the HFD group versus the Chow group. These results provide new insights into the understanding of a microbiome community of obese allergic asthma, and shed light on the functional roles of lung microbiota inducing the pathogenesis of severe asthma.

Effect of You-Gui-Wan on House Dust Mite-Induced Mouse Allergic Asthma via Regulating Amino Acid Metabolic Disorder and Gut Dysbiosis.

Chinese herbal remedies have long been used for enhancing immunity and treating asthma. However, the evidence-based efficacy remains to be supported. This study aimed to explore the potential bio-signatures in allergic asthma and the effect of You-Gui-Wan (YGW), a traditional Chinese herbal prescription, on dust mite-induced mouse allergic asthma. Extract of Dermatophagoides pteronyssinus (Der p), a dust mite, was intratracheally administered to induce allergic asthma in mice. Serum metabolomic and 16S rRNA-based microbiome profiling were used to analyze untargeted metabolites with levels significantly changed and gut microbiota composition, respectively. Results indicated that 10 metabolites (acetylcarnitine, carnitine, hypoxanthine, tryptophan, phenylalanine, norleucine, isoleucine, betaine, methionine, and valine), mainly associated with branched-chain amino acid (BCAA) metabolism, aromatic amino acid (AAA) biosynthesis, and phenylalanine metabolism were markedly elevated after Der p treatment. YGW administration reversed the levels for 7 of the 10 identified metabolites, chiefly affecting BCAA metabolism. On 16S DNA sequencing, disordered Der p-induced gut microbiota was significantly alleviated by YGW. Multiple correlation analysis showed a good correlation between gut microbiota composition and levels of selected metabolites. Our study showed YGW administration effectively alleviated BCAA metabolic disorder and improved gut dysbiosis. This study provides support for YGW administration with benefits for allergic asthma.

Platelets Independently Recruit into Asthmatic Lungs and Models of Allergic Inflammation via CCR3.

Platelet activation and pulmonary recruitment occur in patients with asthma and in animal models of allergic asthma, in which leukocyte infiltration, airway remodeling, and hyperresponsiveness are suppressed by experimental platelet depletion. These observations suggest the importance of platelets to various characteristics of allergic disease, but the mechanisms of platelet migration and location are not understood. The aim of this study was to assess the mechanism of platelet recruitment to extravascular compartments of lungs from patients with asthma and after allergen challenge in mice sensitized to house dust mite (HDM) extract (contains the DerP1 [Dermatophagoides pteronyssinus extract peptidase 1] allergen); in addition, we assessed the role of chemokines in this process. Lung sections were immunohistochemically stained for CD42b+ platelets. Intravital microscopy in allergic mice was used to visualize platelets tagged with an anti–mouse CD49b-PE (phycoerythrin) antibody. Platelet–endothelial interactions were measured in response to HDM (DerP1) exposure in the presence of antagonists to CCR3, CCR4, and CXCR4. Extravascular CD42b+ platelets were detected in the epithelium and submucosa in bronchial biopsy specimens taken from subjects with steroid-naive mild asthma. Platelets were significantly raised in the lung parenchyma from patients with fatal asthma compared with postmortem control-lung tissue. Furthermore, in DerP1-sensitized mice, subsequent HDM exposure induced endothelial rolling, endothelial adhesion, and recruitment of platelets into airway walls, compared with sham-sensitized mice, via a CCR3-dependent mechanism in the absence of aggregation or interactions with leukocytes. Localization of singular, nonaggregated platelets occurs in lungs of patients with asthma. In allergic mice, platelet recruitment occurs via recognized vascular adhesive and migratory events, independently of leukocytes via a CCR3-dependent mechanism.

Investigation of oral atopic diseases: Correlation between geographic tongue and fungiform papillary glossitis

IntroductionThe correlation between oral lesions and atopy is not new, but few studies have investigated the prevalence of mucosal changes in diseases within the atopic spectrum, leading to conflicting data. Some studies found a possible relationship between geographic tongue, transient lingual papillitis and atopic diseases. AimTo investigate the frequency of geographic tongue and fungiform papillary glossitis in patients with atopic diseases, and its correlation with serum IgE levels and skin test results. Material and methodsThe sample was comprised of participants with atopic diseases paired with participants who received negative puncture skin tests. All were submitted to stomatological and medical evaluations, prick test and oral cytopathological. ResultsThe female sex was more numerous in both groups. Mean age was 21 years. A total of 60 diagnoses of atopic diseases were obtained, with allergic rhinitis being the most prevalent. Fungiform papillary glossitis was the most frequent oral lesion in both groups, while geographic tongue was present in 2 cases (2%) in the test group and 2 (2%) in the control group. Atopic patients with fungiform papillary glossitis presented high serum IgE levels. In atopic patients with geographic tongue, the prick test positively identified extracts of Dermatophagoides pteronyssinus (100%) and Dermatophagoides farinae (100%). ConclusionDue to the low frequency of geographic tongue lesions found in the study, it is no possible to conclude if that could be an oral manifestation of atopy. However fungiform papillary glossitis is a common alteration in atopic and non-atopic patients and has a relationship with high IgE serum levels. However, the consolidation of this result requires a larger sample size.

Adjuvanting Allergen Extracts for Sublingual Immunotherapy: Calcitriol Downregulates CXCL8 Production in Primary Sublingual Epithelial Cells.

Application of allergens onto the sublingual epithelium is used to desensitize allergic individuals, a treatment known as sublingual immunotherapy. However, the response of sublingual epithelial cells to house dust mite allergen and potential tolerance-promoting adjuvants such as Toll-like receptor (TLR) ligands and calcitriol has not been investigated. In order to study this, primary sublingual epithelial cells were isolated from dogs and cultured in vitro. After 24-h incubation with a Dermatophagoides farinae extract, a Dermatophagoides pteronyssinus extract, TLR2 ligands (FSL-1, heat-killed Listeria monocytogenes, Pam3CSK4), a TLR3 ligand (poly I:C), a TLR4 ligand [lipopolysaccharide (LPS)], and calcitriol (1,25-dihydroxyvitamin D3), viability of the cells was analyzed using an MTT test, and their secretion of interleukin 6 (IL-6), IL-10, CXCL8, and transforming growth factor β1 (TGF-β1) was measured by enzyme-linked immunosorbent assay. Additionally, to evaluate its potential effect as an adjuvant, sublingual epithelial cells were incubated with calcitriol in combination with a D. farinae extract followed by measurement of CXCL8 secretion. Furthermore, the effect of D. farinae and calcitriol on the transcriptome was assessed by RNA sequencing. The viability of the sublingual epithelial cells was significantly decreased by poly I:C, but not by the other stimuli. CXCL8 secretion was significantly increased by D. farinae extract and all TLR ligands apart from LPS. Calcitriol significantly decreased CXCL8 secretion, and coadministration with D. farinae extract reduced CXCL8 concentrations to levels seen in unstimulated sublingual epithelial cells. Although detectable, TGF-β1 secretion could not be modulated by any of the stimuli. Interleukin 6 and IL-10 could not be detected at the protein or at the mRNA level. It can be concluded that a D. farinae extract and TLR ligands augment the secretion of the proinflammatory chemokine CXCL8, which might interfere with sublingual desensitization. On the other hand, CXCL8 secretion was reduced by coapplication of calcitriol and a D. farinae extract. Calcitriol therefore seems to be a suitable candidate to be used as adjuvant during sublingual immunotherapy.

Laser-facilitated epicutaneous immunotherapy with depigmented house dust mite extract alleviates allergic responses in a mouse model of allergic lung inflammation.

Skin-based immunotherapy of type 1 allergies has recently been re-investigated as an alternative for subcutaneous injections. In the current study, we employed a mouse model of house dust mite (HDM)-induced lung inflammation to explore the potential of laser-facilitated epicutaneous allergen-specific treatment. Mice were sensitized against native Dermatophagoides pteronyssinus extract and repeatedly treated by application of depigmented Dpteronyssinus extract via laser-generated skin micropores or by subcutaneous injection with or without alum. Following aerosol challenges, lung function was determined by whole-body plethysmography and bronchoalveolar lavage fluid was analyzed for cellular composition and cytokine levels. HDM-specific IgG subclass antibodies were determined by ELISA. Serum as well as cell-bound IgE was measured by ELISA, rat basophil leukemia cell assay, and ex vivo using a basophil activation test, respectively. Cultured lymphocytes were analyzed for cytokine secretion profiles and cellular polarization by flow cytometry. Immunization of mice by subcutaneous injection or epicutaneous laser microporation induced comparable IgG antibody levels, but the latter preferentially induced regulatory T cells and in general downregulated T cell cytokine production. This effect was found to be a result of the laser treatment itself, independent from extract application. Epicutaneous treatment of sensitized animals led to induction of blocking IgG, and improvement of lung function, superior compared to the effects of subcutaneous therapy. During the whole therapy schedule, no local or systemic side effects occurred. Allergen-specific immunotherapy with depigmented HDM extract via laser-generated skin micropores offers a safe and effective treatment option for HDM-induced allergy and lung inflammation.

Similarities and differences in the effects of sensitisation and challenge with Dermatophagoides farinae and Dermatophagoides pteronyssinus extracts in a murine asthma surrogate

Patients with atopic asthma may become sensitised to the grain storage mite Dermatophagoides farinae (Der f), the house dust mite Dermatophagoides pteronyssinus (Der p) or both, but thus far little attention has been paid to date to possible variation in their pathophysiological effects. Here we present a side by side comparison of the effects of extracts of these two dust mites in a murine surrogate of atopic asthma. Compared with the Der p-challenged mice, however, the mice-challenged with Der f had favour changes in lung tissue elasticity and expression in matrix metalloproteinases in lung tissue, while the mice challenged with Der p showed more neutrophils infiltrating around the airway and stronger expression of steroid-resistant related cytokines in the lung tissue. Our data suggest that different dust mite crude extracts might lead different pathological characteristics, at least in murine models of asthma.