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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]

Toluene diisocyanate (TDI) is a leading cause of chemical-induced occupational asthma which impacts workers in a variety of industries worldwide. Recently, the robust regulatory potential of regulatory T cells (Tregs) has become apparent, including their functional role in the regulation of allergic disease; however, their function in TDI-induced sensitization has not been explored. To elucidate the kinetics, phenotype, and function of Tregs during TDI sensitization, BALB/c mice were dermally exposed (on each ear) to a single application of TDI (0.5-4% v/v) or acetone vehicle and endpoints were evaluated via RT-PCR and flow cytometry. The draining lymph node (dLN) Treg population expanded significantly 4, 7, and 9 days after single 4% TDI exposure. This population was identified using a variety of surface and intracellular markers and was found to be phenotypically heterogeneous based on increased expression of markers including CD103, CCR6, CTLA4, ICOS, and Neuropilin-1 during TDI sensitization. Tregs isolated from TDI-sensitized mice were significantly more suppressive compared with their control counterparts, further supporting a functional role for Tregs during TDI sensitization. Last, Tregs were depleted prior to TDI sensitization and an intensified sensitization response was observed. Collectively, these data indicate that Tregs exhibit a functional role during TDI sensitization. Because the role of Tregs in TDI sensitization has not been previously elucidated, these data contribute to the understanding of the immunologic mechanisms of chemical induced allergic disease. [ABSTRACT FROM AUTHOR]

Background: The prevalence of asthma and allergic diseases has risen in recent decades. The etiology of asthma and allergic diseases has not been entirely elucidated. Objective: In this study, we investigated the possibility that programmed vaccination in China may have a potential role in asthma and allergic diseases. Methods: In this animal model, newborn BALB/c mice were randomly divided into three groups: vaccine plus ovalbumin (OVA), OVA, and control. The mice of vaccine plus OVA only group were inoculated with vaccines by following the National Vaccines Inoculation Program in China. Mice of vaccine plus OVA and OVA only groups were sensitized and challenged with OVA. Airway hyperresponsiveness was assessed by lung function and serum interleukin (IL) 4 and interferon (IFN) γ were measured. Results: The results of lung function showed that mice of the vaccine plus OVA group exhibited an increase in enhanced pause (Penh) compared with that in the OVA group at methacholine concentrations of 6.25 and 12.5 mg/mL (p < 0.05). Serum IL-4 in the vaccine plus OVA group was higher than that in the OVA group (p < 0.01). The serum IFN-γ level in the OVA group was lower than that in the control group (p < 0.01), and also lower than that in the vaccine plus OVA group (p < 0.05). The ratio of IFN-γ to IL-4 both in the OVA and vaccine plus OVA group was lower than that in the control group (p < 0.01). Conclusions: Results of our study indicated that programmed vaccination in China may have a potential role in the prevalence of asthma and allergic diseases by inducing T-helper 2 cytokine expression and may be responsible for the increasing prevalence of asthma and allergic diseases in China. [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]

Background: Atopic diseases are a major burden of disease on a global scale. Regarding their aetiology, the early years of life are assumed to play a crucial role. In addition, there is growing evidence that elucidating the impact of cross-generational effects and epigenetic mechanisms such as DNA methylation can substantially widen the scientific knowledge of the occurrence and progression of these diseases. We are thus aiming at following the course of asthma, allergies, and potential risk factors for their occurrence across three generations by establishing a birth cohort in the offspring of an existing population-based cohort.Methods/design: 2051 young adults who have been recruited in 1995 for Phase II of the International Study of Asthma and Allergies in Childhood (ISAAC) and who have subsequently been followed-up by the Study on Occupational Allergy Risks (SOLAR) are asked bi-annually since 2009 if they conceived a child in the meantime. If parenthood is reported, parents are invited to enrol along with their children in the ACROSSOLAR cohort. Participation involves completing a questionnaire assessing general and health-related information about the course of the pregnancy and the first year of life of their children. Subsequently, the children are followed up until primary school age when asthma and allergies can be diagnosed reliably. In addition, DNA for epigenetic analysis will be collected and analysed. Longitudinal data analysis techniques will then be used to assess potential associations between early-life exposures and onset of childhood asthma and allergies taking into account epigenetics.Discussion: Birth cohorts are especially suited to elucidate the impact of genetic predisposition, epigenetics, exposures during the first years of life, and gene-environment interactions on the occurrence and progression of asthma and allergies. By building upon an existing cohort, ACROSSOLAR offers a unique and cost-effective opportunity to investigate the aetiology of atopic disease in a prospective and cross-generational way. [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]

Summary: Many reports have been published concerning how psychosocial stress influences the occurrence and progression of allergic diseases such as bronchial asthma and atopic dermatitis. As for asthma, a typical allergic disease often accompanied by psychosomatic related problems, the Global Initiative for Asthma (GINA), international medical guidelines for asthma, describes psychosocial problems as causative factors of poor asthma control and as risk factors for asthma exacerbation, even if symptoms are well controlled. However, because there is little high quality evidence for effective treatments for asthma patients with psychosocial problems, concrete assessments and treatments for such problems is scarcely described in GINA. Therefore, psychosomatic intervention for asthma patients is not effectively conducted on a worldwide scale. In contrast, the "Japanese Guidelines for the Diagnosis and Treatment of Psychosomatic Diseases" describe the assessment and treatment of psychosomatic disorders in detail. In the guidelines, psychosocial factors are classified into five categories; 1) Relation between stress and asthma occurrence or progression, 2) Relation between emotion and asthma symptoms, 3) Problems related to a patient's character and behaviors, 4) Problems of daily life and Quality of Life (QOL), and 5) Problems related to family relationships and life history. The employment of a self-administered questionnaire, the "Psychosomatic Questionnaire related to Asthmatic Occurrence and Progression", is useful for clarifying psychosocial factors and for setting up treatment strategies according to the problems identified. The Japanese guidelines have been proven to be useful, but empirical evidence for their effectiveness is still relatively limited. It will be necessary in the future to accumulate high-quality evidence and to revise the psychosomatic approaches in the guidelines that are universally valid. [ABSTRACT FROM AUTHOR]

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]

Introduction: Humidity is commonly associated with increased airway hyperresponsiveness in asthma. Objective: To examine mold sensitization in patients with allergic asthma or allergic rhinitis and self-reports of humidity as exacerbating factors of clinical symptoms. Methods: A retrospective, cross-sectional study at a University hospital outpatient allergy and asthma clinic was performed. A total of 106 patients with either allergic asthma or allergic rhinitis completed standard prick-puncture skin testing with 17 allergens and controls and completed standardized forms addressing trigger factors for clinical symptoms. Results: Allergic asthmatics sensitized to Cladosporium were more likely to have a more severe asthma severity class (odds ratio = 4.26, confidence interval = 1.30-16.93). Sensitization to Alternaria, Cladosporium, Helminthosporium, Aspergillus and Dermatophagoides pteronyssinus in asthma was associated with higher likelihood for previous hospitalization, while sensitization to Cladosporium, Helminthosporium, Aspergillus, Dermatophagoides pteronyssinus and cockroach in asthma was associated with higher likelihood of having reduced pulmonary function based on forced expiratory volume in 1 s. Furthermore, allergic asthmatics more commonly reported humidity as an exacerbating factor of symptoms than did patients only with allergic rhinitis (68.42% vs 42.86%, respectively; P < 0.05). Conclusion: Mold sensitization is highly associated with more severe asthma, while humidity is more of an exacerbating factor in patients with allergic asthma as compared with allergic rhinitis alone. Further delineation between mold sensitization and humidity is needed to determine whether these are independent factors in asthma. Please cite this paper as: Hayes D Jr, Jhaveri MA, Mannino DM, Strawbridge H and Temprano J. The effect of mold sensitization and humidity upon allergic asthma. Clin Respir J 2013; 7: 135-144. [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]

Abstract: It has been suggested that one possible contributor to the increasing prevalence of atopic (IgE-mediated) allergic diseases and asthma in Europe and the US is exposure to chemicals that may act as adjuvants. Certain commonly used phthalate plasticisers, such as di-(2-ethylhexyl) phthalate, have been implicated in this regard. The evidence for the ability of phthalates to impact on immune and allergic responses has been examined, encompassing epidemiological investigations and results deriving from studies using experimental animals and from analyses in vitro. The epidemiological data provide some evidence that exposure to phthalates may be associated with increased risk of development of allergies and asthma, however, the lack of objective exposure information limits the interpretation. A variety of studies have been performed in mice to examine the influence of phthalate (delivered via various routes of exposure) to impact on immune responses. Measurement of antibody responses is the commonest read out, although other parameters of inflammation such as eosinophil infiltration and cytokine production have been used also. Although certain phthalates, when delivered at appropriate doses, and via an appropriate route, have been reported to impact on immune and inflammatory function in rodents, as yet no consistent pattern has emerged. Results ranged from potentiation of immune or inflammatory responses, to the absence of any effect, to inhibitory or immunosuppressive activity. In addition, comparatively low doses of phthalates have been associated with immune effects only when routes of administration (subcutaneous or intraperitoneal) are used that do not reflect, and are much less relevant for, opportunities for human contact with phthalates. There is clearly a case to be made for the design of more definitive animal studies that will allow development of a more detailed understanding of whether and to what extent, and under what conditions, phthalates are able to effect meaningful changes in immune function that may in turn impact on human health. [Copyright &y& Elsevier]

The article reviews the article "Does Traffic Exhaust Contribute to the Development of Asthma and Allergic Sensitization in Children: Findings From Recent Cohort Studies," by L. Bråbäck and B. Forsberg, which appeared in the periodical "Alternative Medicine Review" in 2009.