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Cockroach allergens can lead to serious allergy and asthma symptoms. Termites are evolutionarily related to cockroaches, cohabitate in human dwellings, and represent an increasing pest problem in the United States. The Formosan subterranean termite (Coptotermes formosanus) is one of the most common species in the southern United States. Several assays were used to determine if C. formosanus termite proteins cross-react with cockroach allergens. Expressed sequence tag and genomic sequencing results were searched for homology to cockroach allergens using BLAST 2.2.21 software. Whole termite extracts were analyzed by mass-spectrometry, immunoassay with IgG and scFv antibodies to cockroach allergens, and human IgE from serum samples of cockroach allergic patients. Expressed sequence tag and genomic sequencing results indicate greater than 60% similarity between predicted termite proteins and German and American cockroach allergens, including Bla g 2/Per a 2, Bla g 3/Per a 3, Bla g 5, Bla g 6/Per a 6, Bla g 7/Per a 7, Bla g 8, Per a 9, and Per a 10. Peptides from whole termite extract were matched to those of the tropomyosin (Bla g 7), arginine kinase (Per a 9), and myosin (Bla g 8) cockroach allergens by mass-spectrometry. Immunoblot and ELISA testing revealed cross-reaction between several proteins with IgG and IgE antibodies to cockroach allergens. Several termite proteins, including the hemocyanin and tropomyosin orthologs of Blag 3 and Bla g 7, were shown to crossreact with cockroach allergens. This work presents support for the hypothesis that termite proteins may act as allergens and the findings could be applied to future allergen characterization, epitope analysis, and clinical studies. [ABSTRACT FROM AUTHOR]

Exposure to indoor allergens plays an important role in the etiology of asthma. This study was designed to quantify indoor allergens from homes of families that had at least one case of childhood asthma at home in a southwestern city of Iran. The relationship between the indoor allergen levels and home characteristics was also investigated. Dust samples were collected from the bedrooms and the kitchens of 35 homes where children with persistent asthma were living. The levels of indoor allergens were measured by enzyme linked immunosorbent assay (ELISA). Detectable amounts of mite, mouse and cockroach allergens were found in all evaluated places. None of our patients were exposed to a threshold concentration of indoor allergen for sensitizing at home. Regarding of mite allergens, the levels of Der f1 were significantly higher than Der p1 and a direct correlation was observed between living in an apartment and Der f1 levels. Moreover, Fel d1 (cat) and Bla g1 (cockroach) allergens were found in the children's bedrooms more frequently than those in the kitchens. In this study, direct associations were obtained between Bla g1 allergen and the duration of occupancy and between Fel d1 and average home size. A total of 34.2% of the patients showed positive skin reactions to at least one of the tested allergens as 17.1% of them showed reactivity to D. pteronyssinus. Proper controlling of cockroaches and mice by public health officials would be a practical approach to avoid inducing asthma or worsening the symptoms. [ABSTRACT FROM AUTHOR]

Cat allergy is one of the most prevalent allergies worldwide and can lead to the development of rhinitis and asthma. Thus far, only allergen extracts from natural sources have been used for allergen-specific immunotherapy. However, extracts and whole allergens in immunotherapy present an anaphylaxis risk. Identification of allergen epitopes or mimotopes has an important role in development of safe and effective allergen-specific immunotherapy. Moreover, with a suitable immunogenic carrier, the absence of sufficient immune response elicited by short peptides could be surmounted. In this study, we identified five structural mimotopes of the major cat allergen Fel d 1 by immunoscreening with random peptide phage libraries. The mimotopes were computationally mapped to the allergen surface, and their IgE reactivity was confirmed using sera from cat-allergic patients. Importantly, the mimotopes showed no basophil activation of the corresponding cat-allergic patients, which makes them good candidates for the development of hypoallergenic vaccine. As bacteriophage particles are becoming increasingly recognized as immunogenic carriers, we constructed bacteriophage particles displaying multiple copies of each selected mimotope on major phage coat protein. These constructed phages elicited T cell-mediated immune response, which was predominated by the type 1 T cell response. Mimotopes alone contributed to the type 1 T cell response by promoting IL-2 production. Fel d 1 mimotopes, as well as their filamentous phage immunogenic carriers, represent promising candidates in the development of hypoallergenic vaccine against cat allergy. [ABSTRACT FROM AUTHOR]

Asthma in the inner city contributes to high morbidity and mortality, and, in school children, reduced school attendance and alteration in academic performance. There is a need to improve asthma care in the inner city by reducing asthma exacerbations. Methods are currently available to predict and prevent seasonal exacerbations of asthma. In addition, new medications are being developed that will be effective in improving pulmonary function and reducing asthma exacerbations. School-centered asthma programs can also be helpful to assist children and clinicians in applying asthma treatment plans and assuring optimal adherence to these plans. [ABSTRACT FROM AUTHOR]

Background: The prevalence of asthma and allergy has recently risen among children. This increase in prevalence might be related to various factors, particularly diet. The aim of this study is to assess the prevalence and association of asthma and allergic sensitization with dietary factors in the French Six Cities Study.Methods: Cross-sectional studies were performed among 7432 schoolchildren aged 9-11 years in Bordeaux, Clermont-Ferrand, Créteil, Marseille, Reims, and Strasbourg. Parental questionnaires, based on the International Study on Asthma and Allergies in Childhood (ISAAC), were used to collect information on allergic diseases and potential exposure factors including a food frequency questionnaire to evaluate dietary habits. Skin prick testing to common allergens for allergic sensitization and bronchial hyper-responsiveness (BHR) testing to exercise were performed. Confounders control was performed with multiple logistic regressions.Results: Asthma symptoms, asthma and allergic sensitization were more prevalent in boys than in girls and were more prevalent in the South than in the North of France. After adjustment for confounders, fruit juice intake was associated with a low prevalence of lifetime asthma (ORa [95 % CI]; 0.73 [0.56-0.97]), butter intake was positively associated with atopic wheeze (1.48 [1.07-2.05]) and having lunch at the canteen 1-2 times/week compared to never or occasionally was associated with a lower prevalence of past year wheeze (0.71 [0.52-0.96]), lifetime asthma (0.76 [0.60-0.96]) and allergic sensitization (0.80 [0.67-0.95]). Meat intake was inversely related to past year wheeze among atopic children (0.68 [0.50-0.98]) while fast food consumption and butter intake were associated with an increase prevalence of asthma (2.39 [1.47-3.93] and 1.51 [1.17-2.00] respectively). Fish intake was associated with a lower prevalence of asthma among non-atopic children (0.61 [0.43-0.87]. None of the dietary factors was associated with BHR.Conclusions: Diet is associated with wheeze, asthma and allergic sensitization but not with BHR in children. These results provide further evidence that adherence to a healthy diet including fruits, meat and fish seems to have a protective effect on asthma and allergy in childhood. However, prospective and experimental studies are needed to provide causal evidence concerning the effect of diet on asthma and atopy. [ABSTRACT FROM AUTHOR]

The article discusses epidemiology, clinical characteristics, and management of occupational asthma. Topics explored include common agents that cause asthma such as animal allergens, plant products, and enzymes, the occupational asthma risks faced by farmers, office workers, and pharmaceutical industry employees, and the effectiveness of immunotherapy in addressing asthma symptoms.

Background: Cockroach (CR) allergens frequently cause severe asthma in CR-sensitized subjects. Allergen-specific immunotherapy causes a shift of allergic Th2 responses towards Th1 and/or regulatory T cell (Treg) responses which reduce airway inflammation and prevent disease progression. Data are relatively limited on immunotherapy via CR allergy vaccine. Methods: The therapeutic efficacy of an intranasal liposome-adjuvant vaccine made of a refined Periplaneta americana arginine kinase (AK) was compared to the liposome-entrapped P. americana crude extract (CRE) vaccine. Adult BALB/c mice were rendered allergic to CRE. Three allergic mouse groups were immunized intranasally on alternate days with 8 doses of liposome-entrapped CRE (L-CRE), liposome-entrapped AK and placebo, respectively. One week later, all mice received a nebulized CRE provocation. Evaluation of vaccine efficacy was performed 1 day after provocation. Results: Liposome-entrapped native AK attenuated airway inflammation after the CRE provocation and caused a shift of allergic Th2 to Th1 and Treg responses. The L-CRE also induced a shift from the Th2 to the Th1 response but did not induce a Treg response and could not attenuate the airway inflammation upon allergen reexposure. Conclusions: Intranasal liposome-adjuvant CR allergy vaccine containing native AK (Per a 9) is better than L-CRE in attenuating allergic airway inflammation. The findings of this study not only document a more comprehensive and beneficial immune response induced by the refined allergen vaccine but also raise the point that the shift from the Th2 to the Th1 response alone might not correlate with improved airway histopathology, clinical outcome and quality of life. Copyright © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Methylene diphenyl diisocyanate (MDI), a low molecular weight chemical important for producing polyurethane foam, coatings, and elastomers is a major cause of occupational asthma, however, mechanisms of disease pathogenesis remain poorly understood. This study characterizes the rearranged germline and hypervariable region cDNA of new anti-MDI secreting hybridomas derived from mice immunized with MDI-conjugated to autologous serum proteins. Six IgG1 secreting clones were identified in initial screening ELISAs, based on differential binding to MDI conjugated human albumin vs. mock exposed albumin. The mAbs secreted by the hybridomas also recognized MDI conjugated to other model proteins (e.g. ovalbumin, transferrin), but did not bind unconjugated proteins, or protein conjugates prepared with other isocyanates (e.g. TDI, HDI). The mAbs displayed MDI-dose dependent binding in ELISA and Western blot, and exhibited varying degrees of cross-competition, suggesting differences in epitope specificity. The cDNA encoding the monoclonal antibodies reveal clonal differences in the CDR3 regions, germline gene usage, and patterns of somatic hypermutation related to epitope specificity. Together, the data provide new insight into the molecular determinants of humoral MDI specificity, and characterize anti-MDI IgG1 mAbs that may be developed into useful diagnostic reagents. [Copyright &y& Elsevier]

Atopic asthma is a chronic inflammatory disease of the lungs generally marked by excessive Th2 inflammation. The role of allergen-specific IgG in asthma is still controversial; however, a receptor of IgG-immune complexes (IgG-ICs), FcγRIII, has been shown to promote Th2 responses through an unknown mechanism. Herein, we demonstrate that allergen-specific IgG-ICs, formed upon reexposure to allergen, promoted Th2 responses in two different models of IC-mediated inflammation that were independent of a preformed T cell memory response. Development of Th2-type airway inflammation was shown to be both FcγRIII and TLR4 dependent, and T cells were necessary and sufficient for this process to occur, even in the absence of type 2 innate lymphoid cells. We sought to identify downstream targets of FcγRIII signaling that could contribute to this process and demonstrated that bone marrow-derived DCs, alveolar macrophages, and respiratory DCs significantly upregulated IL-33 when activated through FcγRIII and TLR4. Importantly, IC-induced Th2 inflammation was dependent on the ST2/IL-33 pathway. Our results suggest that allergen-specific IgG can enhance secondary responses by ligating FcγRIII on antigen-presenting cells to augment development of Th2- mediated responses in the lungs via an IL-33-dependent mechanism. [ABSTRACT FROM AUTHOR]

Thunderstorm asthma is a term used to describe an observed increase in acute bronchospasm cases following the occurrence of thunderstorms in the local vicinity. The roles of accompanying meteorological features and aeroallergens, such as pollen grains and fungal spores, have been studied in an effort to explain why thunderstorm asthma does not accompany all thunderstorms. Despite published evidence being limited and highly variable in quality due to thunderstorm asthma being a rare event, this article reviews this evidence in relation to the role of aeroallergens, meteorological features and the impact of thunderstorm asthma on health services. This review has found that several thunderstorm asthma events have had significant impacts on individuals’ health and health services with a range of different aeroallergens identified. This review also makes recommendations for future public health advice relating to thunderstorm asthma on the basis of this identified evidence. [ABSTRACT FROM AUTHOR]

Background: Experimental data suggest that asthma exacerbation by allergens is enhanced by exposure to environmental tobacco smoke (ETS); however, there is little supporting epidemiologic evidence. To our knowledge, few studies have assessed respiratory symptoms and allergies in this context. Objectives: To evaluate whether the association of exposure to animals (indicators of allergen and endotoxin exposure) with asthma-related symptoms is modified by ETS exposure in Chinese children. Methods: A cross-sectional study of 8,819 children in kindergarten was conducted in 25 districts in northern China. Information on respiratory health and exposure to indoor allergens was obtained using a standard questionnaire from the American Thoracic Society. Results: Among the children with ETS exposure in utero, the effects of exposure to animals were significant with respect to persistent cough [adjusted odds ratio (OR) 1.83; 95% confidence interval (CI) 1.12-2.99] and persistent phlegm (adjusted OR 2.40; 95% CI 1.28-4.54). The combined effect of in utero ETS exposure and animal exposure on doctor-diagnosed asthma was approximately as expected on the basis of their independent effects on an additive scale. There was no interaction between animal exposure and ETS exposure in the first 2 years of life or current ETS exposure. Conclusions: This study provides evidence that animal and ETS exposure increases the risk of asthma-related symptoms in children in kindergarten. ETS exposure in utero did modify the effect of animal exposure on persistent phlegm and persistent cough but not on doctor-diagnosed asthma among children. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Allergy to rodents in the workplace is an important occupational health problem affecting research, pharmaceutical and toxicological sectors and can have a serious impact on employees working in this area. Despite measures to reduce aeroallergen exposures to rodents in the workplace, there are few signs that this occupational health problem is declining. Rodent allergens are well characterized and exposure-response relationships have been demonstrated to be complex. More recently, the importance of rodent allergens outside of the workplace has been demonstrated in several studies of individuals with asthma. This review focuses on rodent allergy both in the workplace and in the home and examines the complex exposure-response relationships between allergen exposure and sensitization and asthma. Risk factors for rodent allergy and mechanisms of tolerance to rodent allergens are discussed. Cite this as: H. Jeal and M. Jones, Clinical & Experimental Allergy, 2010 (40) 1593-1601. [ABSTRACT FROM AUTHOR]

Background: Asthma-associated morbidity is rising, especially in inner city children. Objective: We evaluated the allergen sensitivities, allergen exposures, and associated morbidity for participants in the Inner City Asthma Study. We also determined geographic variations of indoor allergen levels. Methods: Nine hundred thirty-seven inner city children 5 to 11 years old with moderate to severe asthma underwent allergen skin testing. Bedroom dust samples were evaluated for Der p 1, Der f 1, Bla g 1, Fel d 1, and Can f 1. Results: Skin test sensitivities to cockroach (69%), dust mites (62%), and molds (50%) predominated, with marked study site–specific differences. Cockroach sensitivity was highest in the Bronx, New York, and Dallas (81.2%, 78.7%, and 78.5%, respectively), and dust mite sensitivity was highest in Dallas and Seattle (83.7% and 78.0%, respectively). A majority of homes in Chicago, New York, and the Bronx had cockroach allergen levels greater than 2 U/g, and a majority of those in Dallas and Seattle had dust mite allergen levels greater than 2 μg/g. Levels of both of these allergens were influenced by housing type. Cockroach allergen levels were highest in high-rise apartments, whereas dust mite allergen levels were highest in detached homes. Children who were both sensitive and exposed to cockroach allergen had significantly more asthma symptom days, more caretaker interrupted sleep, and more school days missed than children who were not sensitive or exposed. Conclusion: Geographic differences in allergen exposure and sensitivity exist among inner city children. Cockroach exposure and sensitivity predominate in the Northeast, whereas dust mite exposure and sensitivity are highest in the South and Northwest. Cockroach allergen appears to have a greater effect on asthma morbidity than dust mite or pet allergen in these children. [ABSTRACT FROM AUTHOR]