NMR residual dipolar couplings investigation in the topology of house dust mite Group V allergens.

Blo t 5 is an important major allergen protein from Blomia tropicalis mites, which are prevalent in tropical and subtropical regions, including Taiwan. It is a coiled-coil triple helical bundle, but there currently is ambiguity around its structural fold and packing of the three helices. We have relied on NMR residual dipolar coupling data collected from four different alignment media to confirm that Blo t 5 has left-handed helical topology and further used that data to refine its solution structure. Earlier we had described conformational epitope for a detection monoclonal antibody by exclusive use of TROSY NMR experiments that studied Blo t 5 binding with the antibody FAB' fragment. Here, we confirm those findings with an extensive mutagenesis and biophysical study to validate the NMR epitope mapping approach proposed by us.

The genome-wide response of Dermatophagoides pteronyssinus to cystatin A, a peptidase inhibitor from human skin, sheds light on its digestive physiology and allergenicity.

The digestive physiology of house dust mites (HDMs) is particularly relevant for their allergenicity since many of their allergens participate in digestion and are excreted into faecal pellets, a main source of exposure for allergic subjects. To gain insight into the mite dietary digestion, the genome of the HDM Dermatophagoides pteronyssinus was screened for genes encoding peptidases (n = 320), glycosylases (n = 77), lipases and esterases (n = 320), peptidase inhibitors (n = 65) and allergen-related proteins (n = 52). Basal gene expression and transcriptional responses of mites to dietary cystatin A, a cysteine endopeptidase inhibitor with previously shown antinutritional effect on mites, were analysed by RNAseq. The ingestion of cystatin A resulted in significant regulation of different cysteine endopeptidase and glycosylase genes. One Der p 1-like and two cathepsin B-like cysteine endopeptidase genes of high basal expression were induced, which suggests their prominent role in proteolytic digestion together with major allergen Der p 1. A number of genes putatively participating in the interaction of mites with their microbiota and acquired by horizontal gene transfer were repressed, including genes encoding the peptidase Der p 38, two 1,3-beta-glucanases, a lysozyme and a GH19 chitinase. Finally, the disruption of mite digestion resulted in the regulation of up to 17 allergen and isoallergen genes. Altogether, our results shed light on the putative role of specific genes in digestion and illustrate the connection between the digestive physiology of HDM and allergy.

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

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

A Case-Control Study Comparing the General Characteristics of Patients with Symptomatic Dermographism and Chronic Spontaneous Urticaria: Is Atopy a Risk Factor for Symptomatic Dermographism?

INTRODUCTION: Symptomatic dermographism (SDerm) is the most common chronic inducible urticaria (CIndU) subtype. There is still limited information in the literature about clinical features, triggering factors, and accompanying comorbidities of SDerm. The aim of this study was to compare the clinical features and laboratory data of patients with SDerm and chronic spontaneous urticaria (CSU). METHODS: The clinical features and laboratory data of patients with SDerm and CSU were compared retrospectively. The laboratory data and general characteristic features of the patients were obtained from the medical records. RESULTS: The study included a total of 361 patients (CSU: 220, SDerm: 141). The rates of asthma (odds ratio [OR]: 1.79, p = 0.036), allergic rhinitis (OR: 6.03, p < 0.001), and thyroid disease (OR: 1.78, p = 0.039) were higher in patients with SDerm. The disease duration (median 12 months, p < 0.001) and regular antihistamine use (OR: 0.31, p < 0.001) were lower in patients with SDerm. Total IgE level (median: 193, p < 0.001), thyroid antibody positivity (OR: 1.93, p = 0.039), and atopy (OR: 8.81, p < 0.001) were higher in patients with SDerm. Dermatophagoides pteronyssinus (OR: 17.72, p < 0.001), Dermatophagoides farinae (OR: 17.20, p < 0.001), grass pollen (OR: 2.50, p < 0.026), cat epithelium (OR: 3.68, p < 0.023), and cockroach (OR: 4.93, p < 0.009) allergen positivity rates were higher in patients with SDerm. CONCLUSION: Atopic diseases such as asthma and allergic rhinitis and the sensitization rate to aeroallergens seem to be higher in patients with SDerm than in patients with CSU. The results of this study should be supported by multicenter studies of patients from different geographical regions.

Differences in molecular sensitization profiles between a Spanish and Latin American mite allergic patients.

BACKGROUND AND OBJECTIVE: To analyze the sensitization pattern to Dermatophagoides pteronyssinus and to associate the diagnostic findings and clinical severity in 218 allergic patients from two different continents. METHODS: Mite allergic patients were recruited by the Allergology departments from Latin America (n=88: Colombia, Costa Rica and Guatemala) and Spain (N=130). All patients had allergic rhinitis with or without asthma and positive skin prick test results to D. pteronyssinus. Specific IgE levels to D. pteronyssinus, D. farinae, Der p 1, Der p 2, and Der p 23 were quantified by ImmunoCAP system (ThermoFisher Scientific). Allergenic profile was also determined by western blot. Comparative Statistical analysis was performed by GraphPad software. RESULTS: Patients recognized most frequently Der p 2 (79%) followed by Der p 1 (73%), and Der p 23 (69%) allergens. The percentage of asthmatic patients increases with the number of sensitizations however none statistically significant differences were found. Interestingly, asthmatic patients presented the highest median levels of total IgE and specific IgE levels of D. pteronyssinus and molecular allergens, mainly Der p 2. Analysing the two different populations, Spanish patients were predominantly sensitized to Der p 2 (88.46%) and Der p 1 (83.84%), whereas Latin American population were more sensitized to Der p 23. CONCLUSION: Our data support the relevance of Der p 2 in mite allergy as the major allergen, with the high number of patients sensitized to it and its importance in the development of asthma. Sensitization to Der p 23 was more important in Latin America.

IgE-Mediated Sensitization to Blo t 21 and Blo t 5 Is Associated With Asthma in the Tropics: A Case-Control Study.

BACKGROUND AND OBJECTIVE: Sensitization to Blomia tropicalis is associated with asthma in various tropical and subtropical countries; however, information about the specific molecular components associated with this disease is scarce. Using molecular diagnosis, we sought to identify B tropicalis allergens associated with asthma in Colombia. METHODS: Specific IgE (sIgE) to 8 B tropicalis recombinant allergens (Blo t 2, 5, 7, 8, 10, 12, 13, and 21) was determined using an in-house ELISA system in asthma patients (n=272) and controls (n=298) recruited in a national prevalence study performed in several Colombian cities (Barranquilla, Bogotá, Medellín, Cali, and San Andrés). The study sample included children and adults (mean [SD] age, 28 [17] years). Cross-reactivity between Blo t 5 and Blo t 21 was evaluated using ELISA-inhibition. RESULTS: Specific IgE (sIgE) to 8 B tropicalis recombinant allergens (Blo t 2, 5, 7, 8, 10, 12, 13, and 21) was determined using an in-house ELISA system in asthma patients (n=272) and controls (n=298) recruited in a national prevalence study performed in several Colombian cities (Barranquilla, Bogotá, Medellín, Cali, and San Andrés). The study sample included children and adults (mean [SD] age, 28 [17] years). Cross-reactivity between Blo t 5 and Blo t 21 was evaluated using ELISA-inhibition. CONCLUSION: Although Blo t 5 and Blo t 21 are considered common sensitizers, this is the first report of their association with asthma. Both components should be included in molecular panels for diagnosis of allergy in the tropics.

Inactivation of common airborne antigens by perfluoroalkyl chemicals modulates early life allergic asthma.

Allergic asthma, driven by T helper 2 cell-mediated immune responses to common environmental antigens, remains the most common respiratory disease in children. Perfluorinated chemicals (PFCs) are environmental contaminants of great concern, because of their wide application, persistence in the environment, and bioaccumulation. PFCs associate with immunological disorders including asthma and attenuate immune responses to vaccines. The influence of PFCs on the immunological response to allergens during childhood is unknown. We report here that a major PFC, perfluorooctane sulfonate (PFOS), inactivates house dust mite (HDM) to dampen 5-wk-old, early weaned mice from developing HDM-induced allergic asthma. PFOS further attenuates the asthma protective effect of the microbial product lipopolysaccharide (LPS). We demonstrate that PFOS prevents desensitization of lung epithelia by LPS, thus abolishing the latter's protective effect. A close mechanistic study reveals that PFOS specifically binds the major HDM allergen Der p1 with high affinity as well as the lipid A moiety of LPS, leading to the inactivation of both antigens. Moreover, PFOS at physiological human (nanomolar) concentrations inactivates Der p1 from HDM and LPS in vitro, although higher doses did not cause further inactivation because of possible formation of PFOS aggregates. This PFOS-induced neutralization of LPS has been further validated in primary human cell models and extended to an in vivo bacterial infection mouse model. This study demonstrates that early life exposure of mice to a PFC blunts airway antigen bioactivity to modulate pulmonary inflammatory responses, which may adversely affect early pulmonary health.

Efficacy and tolerability of house dust mites subcutaneous immunotherapy with monomeric allergoid: an Italian multicenter study.

Summary: Background. Subcutaneous immunotherapy is an effective treatment of respiratory allergy and allergoids offer a treatment option characterized by reduced IgE-binding properties to improve the safety profile. Purpose of this study was to investigate the efficacy and the safety of an injective monomeric allergoid in patients with moderate to severe persistent allergic rhinitis due to house dust mites. Methods. in a perspective, controlled, observational study a suspension of 0.70 mL at 10 BU/mL containing a mixture of carbamylated extract of Dermatophagoides was injected monthly for 12 months, following a 5-weeks build-up phase (0.10-0.20-0.30-0.50-0.70 mL weekly), to 58 patients (mean age 25.1 ± 12.7). A matching group of 60 patients (mean age 34.0 ± 14.2) was observed as control, and both groups were allowed to assume standard pharmacotherapy. After one year, changes from baseline in visual analogue scale for symptoms and drugs intake were compared; satisfaction rate was based on patients' and physicians' judgements. Results. In respect to baseline both groups showed an improvement in symptoms with a significant difference in favor of immunotherapy. Drugs intake was significantly lower in patients receiving injections. High level of agreement was found between doctors and patients on their rate of satisfaction. No serious reactions occurred, and at least a mild episodic local or systemic reaction was reported by a limited number of patients. Conclusions. In routine practice injective monomeric allergoid of house dust mites was safe and associated with a perceived significant clinical benefit in persistent rhinitis shown by objective and subjective outcomes.

Update on the role of genetic factors, environmental factors and allergens in canine atopic dermatitis.

BACKGROUND: Canine atopic dermatitis (cAD) is a common, complex and multifactorial disease involving, among others, genetic predisposition, environmental factors and allergic sensitisation. OBJECTIVE: This review summarises the current evidence on the role of genetic and environmental factors and allergic sensitisation in the pathogenesis of cAD since the last review by ICADA in 2015. MATERIALS AND METHODS: Online citation databases and proceedings from international meetings on genetic factors, environmental factors and allergens relevant to cAD that had been published between 2015 and 2022 were reviewed. RESULTS: Despite intensive research efforts, the detailed genetic background predisposing to cAD and the effect of a wide range of environmental factors still need more clarification. Genome-wide association studies and investigations on genetic biomarkers, such as microRNAs, have provided some new information. Environmental factors appear to play a major role. Lifestyle, especially during puppyhood, appears to have an important impact on the developing immune system. Factors such as growing up in a rural environment, large size of family, contact with other animals, and a nonprocessed meat-based diet may reduce the risk for subsequent development of cAD. It appears that Toxocara canis infection may have a protective effect against Dermatophagoides farinae-induced cAD. House dust mites (D. farinae and D. pteronyssinus) remain the most common allergen group to which atopic dogs react. Currently, the major allergens related to D. farinae in dogs include Der f 2, Der f 15, Der f 18 and Zen 1. CONCLUSIONS AND CLINICAL RELEVANCE: Canine atopic dermatitis remains a complex, genetically heterogeneous disease that is influenced by multiple environmental factors. Further, well-designed studies are necessary to shed more light on the role of genetics, environmental factors and major allergens in the pathogenesis of cAD.

Rapid induction of allergen-blocking IgG in dogs vaccinated with plant-based, Der f 2-expressing bioparticles.

BACKGROUND: Allergen-carrying virus-like particles are effective and safe means of allergen immunotherapy (AIT) in rodent models. OBJECTIVE: To study the development of allergen-blocking immunoglobulin (Ig)G in dogs injected with Der f 2-carrying enveloped plant-based bioparticles (eBPs). MATERIALS AND METHODS: Laboratory beagle dogs were injected intradermally (ID) or subcutaneously (SC) with Der f 2-eBP three times at 2-week intervals. A basophil mediator release assay was used to compare the reactivity of Der f 2-eBPs to that of recombinant Der f 2. Allergen-specific IgG serum levels were determined by immunoblotting and ELISA. The allergen-blocking potential of postvaccination IgG was assessed by Pet Allergy Xplorer (PAX) macroarray and basophil mediator release inhibition assays. RESULTS: The amount of Der f 2 eBPs needed to induce basophil activation was 1000-fold higher than that of the soluble natural allergen. In both immunisation groups, eBP injections caused no adverse events and induced Der f 2-specific IgG, first detected on Day (D)14 and peaking on D41. The co-incubation of sera with a Der f 2-IgE-rich canine serum pool resulted in a mean PAX inhibition of 70% (ID) to 80% (SC) on D41. For both groups, the inhibition of basophil mediator release reached 75% on D28 and D41. The percentage inhibition of PAX and mediator release correlated significantly with Der f 2 IgG levels. CONCLUSION AND CLINICAL RELEVANCE: Intradermal and subcutaneous injections of Der f 2-eBPs were safe and increased Der f 2-specific IgG. The clinical benefit of immunotherapy will be evaluated in future trials enrolling atopic dogs allergic to house dust mites.

The Impact of High-Fructose Diet and Co-Sensitization to House Dust Mites and Ragweed Pollen on the Modulation of Airway Reactivity and Serum Biomarkers in Rats.

The topic of ragweed pollen (RW) versus house dust mites (HDMs) has often been deliberated, but the increasing incidence of co-sensitization between them has been scarcely addressed. Utilizing Sprague Dawley rats, we explored the effects of co-sensitization with the combination of HDMs and RW pollen extracts in correlation with high-fructose diet (HFrD) by in vitro tracheal reactivity analysis in isolated organ bath and biological explorations. Our findings unveiled interrelated connections between allergic asthma, dyslipidemia, and HFrD-induced obesity, shedding light on their compounding role through inflammation. The increased CRP values and airway hyperresponsiveness to the methacholine challenge suggest a synergistic effect of obesity on amplifying the existing inflammation induced by asthma. One of the major outcomes is that the co-sensitization to HDMs and RW pollen led to the development of a severe allergic asthma phenotype in rats, especially in those with HFrD. Therefore, the co-sensitization to these allergens as well as the HFrD may play a crucial role in the modulation of systemic inflammation, obesity, and airway reactivity.

Optimization of Basophil Activation Test in the Diagnosis and Qualification for Allergen-Specific Immunotherapy in Children with Respiratory Allergy to the House Dust Mite Dermatophagoides pteronyssinus.

The aim of this study was to optimize a basophil activation test in the detection of allergy to the house dust mite Dermatophagoides pteronyssinus in children with allergic respiratory diseases. This study involved 32 cases, 13 girls and 19 boys aged 4-17 years, with perennial asthma or allergic rhinitis caused by D. pteronyssinus. The control group consisted of 13 girls and 19 boys aged 4-17 years with seasonal allergic asthma or rhinitis provoked by Timothy or birch pollen. House dust mite (HDM) allergy was excluded in the controls based on their medical history, skin prick test (SPT) results and sIgE determination. In all patients, a basophil activation test (BAT) was performed with five dilutions of D. pteronyssinus allergen (the dilution series ranged from 22.5 to 0.00225 ng/mL). The results were analyzed by using the receiver operating characteristics (ROC) to determine the optimal allergen concentrations, outcome measures and cut-off points that would differentiate most accurately between HDM-allergic and non-allergic patients. As a "gold standard", criteria for allergen-specific immunotherapy with D. pteronyssinus or respective pollens were applied by an experienced pediatric allergist following the guidelines of the European Academy of Allergy and Clinical Immunology. The highest diagnostic efficiency was yielded by the protocol assuming a cut-off value of 9.76% activated basophils after activation with a single allergen concentration of 2.25 ng/mL (sensitivity 90.6%, specificity 100%). This protocol yielded 3 (4.7%) misclassifications, all false negative, when compared with the "gold standard". There was a strong correlation with the BAT results at 22.5, 2.25 and 0.225 ng/mL (respectively r = 0.90 and r = 0.78, p < 0.001), as well as between the BAT at 2.25 ng/mL and SPT (r = 0.82, p < 0.001) and between the SPT and sIgE levels (r = 0.78, p < 0.001). High cross-reactivity between D. pteronyssinus and D. farinae was confirmed based on the BAT at 22.5 ng/mL (r = 0.82, p < 0.001). In conclusion, the BAT showed very good concordance with the result of a meticulous process of decision-making that combined validated allergy tests (SPT, sIgE) with expert guidelines, specialist knowledge and experience. Facing the risk of the incorrect qualification of patients for costly, long-lasting and potentially risky allergen-specific immunotherapy, the inclusion of a basophil activation test into diagnostic process seems fully justified.

A micropeptide TREMP encoded by lincR-PPP2R5C promotes Th2 cell differentiation by interacting with PYCR1 in allergic airway inflammation.

BACKGROUND: Allergic asthma is largely dominated by Th2 lymphocytes. Micropeptides in Th2 cells and asthma remain unmasked. Here, we aimed to demonstrate a micropeptide, T-cell regulatory micropeptide (TREMP), in Th2 cell differentiation in asthma. METHODS: TREMP translated from lincR-PPP2R5C was validated using Western blotting and mass spectrometry. TREMP knockout mice were generated using CRISPR/Cas9. Coimmunoprecipitation revealed that TREMP targeted pyrroline-5-carboxylate reductase 1 (PYCR1), which was further explored in vitro and in vivo. The levels of TREMP and PYCR1 in Th2 cells from clinical samples were determined by flow cytometry. RESULTS: TREMP, encoded by lincR-PPP2R5C, was in the mitochondrion. The lentivirus encoding TREMP promoted Th2 cell differentiation. In contrast, Th2 differentiation was suppressed in TREMP-/- CD4+ T cells. In the HDM-induced model of allergic airway inflammation, TREMP was increased in pulmonary tissues. Allergic airway inflammation was relieved in TREMP-/- mice treated with HDM. Mechanistically, TREMP interacted with PYCR1, which regulated Th2 differentiation via glycolysis. Glycolysis was decreased in Th2 cells from TREMP-/- mice and PYCR1-/- mice. Similar to TREMP-/- mice, allergic airway inflammation was mitigated in HDM-challenged PYCR1-/- mice. Moreover, we measured TREMP and PYCR1 in asthma patients. And we found that, compared with those in healthy controls, the levels of TREMP and PYCR1 in Th2 cells were significantly increased in asthmatic patients. CONCLUSIONS: The micropeptide TREMP encoded by lincR-PPP2R5C promoted Th2 differentiation in allergic airway inflammation by interacting with PYCR1 and enhancing glycolysis. Our findings highlight the importance of neglected micropeptides from noncoding RNAs in allergic diseases.

Dermatophagoides pteronyssinus proteins and their role in the diagnostics and management of house dust mite allergy: exploring allergenic components.

Component-resolved diagnostics enables the detection of allergen-specific immunoglobulins E (asIgE) to house dust mite (HDM) proteins, which may help clinicians to face the difficulties in diagnostics of HDM allergy. Currently, almost 40 proteins of Dermatophagoides species, that are able to bind asIgE, have been identified, and this number will certainly increase. The association between sensitisation to particular molecules and allergy symptoms is extensively studied. This investigation enables us to identify HDM molecules that promote respiratory, skin, or food allergies, and it could help us predict the possible course of allergic diseases. The individual repertoire of asIgE improves our understanding of immunological response, which underlies allergy symptoms, and helps to form individual therapeutic regimens. This review provides clinicians with information on Dermatophagoides pteronyssinus proteins available in commercial arrays, and their role in the diagnostics and management of HDM allergy.

RNA viruses alter house dust mite physiology and allergen production with no detected consequences for allergenicity.

RNA viruses have recently been detected in association with house dust mites, including laboratory cultures, dust samples, and mite-derived pharmaceuticals used for allergy diagnosis. This study aimed to assess the incidence of viral infection on Dermatophagoides pteronyssinus physiology and on the allergenic performance of extracts derived from its culture. Transcriptional changes between genetically identical control and virus-infected mite colonies were analysed by RNAseq with the support of a new D. pteronyssinus high-quality annotated genome (56.8 Mb, 108 scaffolds, N50 = 2.73 Mb, 96.7% BUSCO-completeness). Extracts of cultures and bodies from both colonies were compared by inspecting major allergen accumulation by enzyme-linked immunosorbent assay (ELISA), allergen-related enzymatic activities by specific assays, airway inflammation in a mouse model of allergic asthma, and binding to allergic patient's sera IgE by ImmunoCAP. Viral infection induced a significant transcriptional response, including several immunity and stress-response genes, and affected the expression of seven allergens, putative isoallergens and allergen orthologs. Major allergens were unaffected except for Der p 23 that was upregulated, increasing ELISA titers up to 29% in infected-mite extracts. By contrast, serine protease allergens Der p 3, 6 and 9 were downregulated, being trypsin and chymotrypsin enzymatic activities reduced up to 21% in extracts. None of the parameters analysed in our mouse model, nor binding to human IgE were significantly different when comparing control and infected-mite extracts. Despite the described physiological impact of viral infection on the mites, no significant consequences for the allergenicity of derived extracts or their practical use in allergy diagnosis have been detected.

Targeted suppression of Dpt-specific B cells in humanized Rag2- γc- mouse model of HDM allergy.

Der p 1 is one of the major allergenic molecules of Dermatophagoides pteronyssinus, causing house dust mite (HDM) allergy. The pathological B cells produce allergen-specific IgE antibodies that mediate the hypersensitivity reaction, therefore the selective elimination of these B cells is a legitimate therapeutic goal in allergy. Chimeric molecule Dp51-72 able to cross-link B cell inhibitory complement receptor type 1 and BCR on Der p 1-specific B cells was constructed. The signalling capabilities of this molecule have been tested on human B cells. A humanized mouse model of HDM allergy has been used to test the in vivo effects of the chimeric molecule administration. Administering the chimeric molecule to immunodeficient Rag2- γc- mice transferred with PBMCs from allergic patients resulted in reduction of allergen-specific IgE antibodies in the sera, and reduced infiltration of immune cells in lung histology preparations. Reduced numbers of human CD45+ and CD4+ cells in the lungs as well as inhibition of mast cell degranulation were also observed. The treatment with Dp51-72 chimera significantly decreased the local levels of anti-Dpt IgE antibodies in the bronchoalveolar lavage fluid (BALF). The binding of the chimeric molecule to tonsillar B cells triggers the tyrosine phosphorylation of 30-32 kDa protein, which is most likely involved in the inhibitory process. Administration of constructed chimeric molecules to humanized mice with developed inflammation resulted in specific suppression of disease-associated IgE antibody-producing cells and preserved lung histology. This effective approach could be further developed into a therapeutic agent for treatment of patients with HDM allergy.

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/EBPß 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.

The Relationship of Parasite Allergens to Allergic Diseases.

PURPOSE OF REVIEW: Helminth infections modify the natural history of allergic diseases, by either decreasing or increasing their symptoms. Several helminth components are involved in the increasing of the allergic response and symptoms, overcoming the concomitant immunosuppression of helminthiases. However, the role of individual IgE-binding molecules in this process remains to be defined. RECENT FINDINGS: We updated the list of helminth allergens and IgE-binding molecules, their effects on asthma presentation, and their impact on allergy diagnosis. Data from genetic and epigenetic studies of ascariasis are analyzed. A new species-specific A. lumbricoides allergen has been discovered, with potential use in molecular diagnosis. Most helminth IgE-binding components are not officially classified as allergens in the WHO/IUIS database, although there is evidence of their influence increasing allergic manifestations. Further immunological characterization of these components is needed to better understand their mechanisms of action and evaluate the ways in which they can influence the diagnosis of allergy.

IgE sensitization to Blo t 21 and Blo t 5 is associated with asthma in the tropics: a case-control study.

BACKGROUND AND OBJECTIVES: Blomia tropicalis sensitization is associated with asthma in different tropical and sub-tropical countries; however, information about the specific molecular components associated with this disease is scarce. Using molecular diagnosis, we sought to identify B. tropicalis allergens associated with asthma in Colombia. METHODS: Specific IgE (sIgE) to eight B. tropicalis recombinant allergens (Blo t 2/5/7/8/10/12/13 and 21) was determined using an in-house developed ELISA system in asthmatic patients (n=272) and control subjects (n=298) recruited in a national prevalencestudy performed in Colombian cities (Barranquilla, Bogotá, Medellín, Cali and San Andrés). Sample study included children and adults (mean age: 28±SD 17 years old). Cross-reactivity between Blot 5 and Blo t 21 was evaluated by ELISA-inhibition. RESULTS: Sensitization to Blo t 21 (aOR: 1.9; 95% CI: 1.2 - 2.9) and Blo t 5 (aOR: 1.6; 95%CI: 1.1 - 2.5), but not Blo t 2, was associated with asthma. sIgE levels to Blo t 21 and to Blo t 5 were significantly higher in the disease group. Cross-reactivity between Blo t 21 and Blo t 5 is on average moderate; however, individual analysis indicates that may be high (>50%) in some cases. CONCLUSIONS: Although Blo t 5 and Blo t 21 has been described as common sensitizers, this is the first report of their association with asthma. Both components should be included in molecular panels for allergy diagnosis in the tropics.

Molecular sensitization pattern to house dust mites is formed from the first years of life and includes group 1, 2, Der p 23, Der p 5, Der p 7 and Der p 21 allergens.

BACKGROUND: As the process and nature of developing sensitivity to house dust mites (HDMs) remain not fully studied, our goal was to establish the pattern, nature and timeframe of house dust mite (HDM) sensitization development in patients in Ukraine as well as the period when treatment of such patients would be most effective. METHODS: The data of the multiplex allergy test Alex2 was collected from 20,033 patients. To determine age specifics of sensitization, descriptive statistics were used. Bayesian Network analysis was used to build probabilistic patterns of individual sensitization. RESULTS: Patients from Ukraine were most often sensitized to HDM allergens of group 1 (Der p 1, Der f 1) and group 2 (Der p 2, Der f 2) as well as to Der p 23 (55%). A considerable sensitivity to Der p 5, Der p 7 and Der p 21 allergens was also observed. The overall nature of sensitization to HDM allergens among the population of Ukraine is formed within the first year of life. By this time, there is a pronounced sensitization to HDM allergens of groups 1 and 2 as well as to Der p 23. Significance of sensitization to Der p 5, Der p 7 and Der p 21 allergens grows starting from the age of 3-6. Bayesian Network data analysis indicated the leading role of sensitization to Der p 1 and Der f 2. While developing the sensitivity to group 5 allergens, the leading role may belong to Der p 21 allergen. CONCLUSION: The results obtained indicate the importance of determining the sensitization profile using the multi-component approach. A more detailed study of the optimal age for AIT prescription is required as the pattern of sensitization to HDMs is formed during the first year of life.