A comparison of skin prick tests, intradermal skin tests, and specific IgE in the diagnosis of mouse allergy.

PubMed

Sharma, Hemant P; Wood, Robert A; Bravo, Andrea R; Matsui, Elizabeth C

2008-04-01

Mouse sensitization is assessed by using skin testing and serum levels of mouse allergen-specific IgE (m-IgE). However, it is unknown whether a positive skin test response or m-IgE result accurately identifies those with clinically relevant mouse sensitization. We sought to compare skin testing and m-IgE measurement in the diagnosis of mouse allergy. Sixty-nine mouse laboratory workers underwent skin prick tests (SPTs), intradermal tests (IDTs), and serum IgE measurements to mouse allergen, followed by nasal challenge to increasing concentrations of mouse allergen. Challenge response was assessed by nasal symptom score. Thirty-eight women and 31 men with a mean age of 30 years were studied. Forty-nine workers reported mouse-related symptoms, of whom 10 had positive m-IgE results and 12 had positive SPT responses. Fifteen had negative SPT responses but positive IDT responses. Positive nasal challenges were observed in 70% of workers with positive m-IgE results, 83% of workers with positive SPT responses, 33% of workers with negative SPT responses/positive IDT responses, and 0% of workers with negative IDT responses. SPTs performed best, having the highest positive and negative predictive values. Among participants with a positive challenge result, those with a positive SPT response or m-IgE result had a significantly lower challenge threshold than those with a positive IDT response (P = .01). Workers with a positive challenge result were more likely to have an increase in nasal eosinophilia after the challenge compared with those with a negative challenge result (P = .03). SPTs perform best in discriminating patients with and without mouse allergy. Mouse-specific IgE and IDTs appear to be less useful than SPTs in the diagnosis of mouse allergy.

Comparison of immunoglobulin E measurements on IMMULITE and ImmunoCAP in samples consisting of allergen-specific mouse-human chimeric monoclonal antibodies towards allergen extracts and four recombinant allergens.

PubMed

Szecsi, Pal B; Stender, Steen

2013-01-01

Specific immunoglobulin E (IgE) antibody in vitro tests are performed on enzyme immunoassay systems. Poor agreement among systems has been reported and comparisons have been made exclusively with allergen extracts - not with recombinant allergens. Here we compare the ImmunoCAP and the IMMULITE systems. Ten patient samples with positive IgE toward egg white, birch pollen or cat or dog dander were compared using allergen extracts or the recombinant allergens Gal d 1, Bet v 1, Fel d 1 and Can f 1 with the two assay systems. Comparisons were also performed using four monoclonal mouse-human chimeric IgE antibodies specific for the same allergenic components. IMMULITE estimated a higher allergen-specific IgE concentration in sera than ImmunoCAP when testing with allergen extracts as well as recombinant allergens. The chimeric antibodies gave an equivalent response in the total IgE and specific IgE (sIgE) with an average ratio of 1.08 (range 0.9-1.3) on ImmunoCAP. In contrast, IMMULITE exhibited sIgE signals that were substantially higher than the summed level of IgE for all four chimeric antibodies (average ratio 2.96 and range 1.7-4.3). Comparison using chimeric antibodies allowed the evaluation of the true performance of the systems. ImmunoCAP measured total IgE and sIgE equally, whereas IMMULITE displayed higher sIgE signals when compared to the summed level of total IgE for all four chimeric antibodies. Results obtained with the two assay systems are not interchangeable by means of mathematical conversion. Copyright © 2013 S. Karger AG, Basel.

Blocking antibodies induced by immunization with a hypoallergenic parvalbumin mutant reduce allergic symptoms in a mouse model of fish allergy

PubMed Central

Freidl, Raphaela; Gstoettner, Antonia; Baranyi, Ulrike; Swoboda, Ines; Stolz, Frank; Focke-Tejkl, Margarete; Wekerle, Thomas; van Ree, Ronald; Valenta, Rudolf; Linhart, Birgit

2017-01-01

Background Fish is a frequent elicitor of severe IgE-mediated allergic reactions. Beside avoidance, there is currently no allergen-specific therapy available. Hypoallergenic variants of the major fish allergen, parvalbumin, for specific immunotherapy based on mutation of the 2 calcium-binding sites have been developed. Objectives This study sought to establish a mouse model of fish allergy resembling human disease and to investigate whether mouse and rabbit IgG antibodies induced by immunization with a hypoallergenic mutant of the major carp allergen protect against allergic symptoms in sensitized mice. Methods C3H/HeJ mice were sensitized with recombinant wildtype Cyp c 1 or carp extract by intragastric gavage. Antibody, cellular immune responses, and epitope specificity in sensitized mice were investigated by ELISA, rat basophil leukemia assay, T-cell proliferation experiments using recombinant wildtype Cyp c 1, and overlapping peptides spanning the Cyp c 1 sequence. Anti-hypoallergenic Cyp c 1 mutant mouse and rabbit sera were tested for their ability to inhibit IgE recognition of Cyp c 1, Cyp c 1–specific basophil degranulation, and Cyp c 1–induced allergic symptoms in the mouse model. Results A mouse model of fish allergy mimicking human disease regarding IgE epitope recognition and symptoms as close as possible was established. Administration of antisera generated in mice and rabbits by immunization with a hypoallergenic Cyp c 1 mutant inhibited IgE binding to Cyp c 1, Cyp c 1–induced basophil degranulation, and allergic symptoms caused by allergen challenge in sensitized mice. Conclusions Antibodies induced by immunization with a hypoallergenic Cyp c 1 mutant protect against allergic reactions in a murine model of fish allergy. PMID:27876628

Blocking antibodies induced by immunization with a hypoallergenic parvalbumin mutant reduce allergic symptoms in a mouse model of fish allergy.

PubMed

Freidl, Raphaela; Gstoettner, Antonia; Baranyi, Ulrike; Swoboda, Ines; Stolz, Frank; Focke-Tejkl, Margarete; Wekerle, Thomas; van Ree, Ronald; Valenta, Rudolf; Linhart, Birgit

2017-06-01

Fish is a frequent elicitor of severe IgE-mediated allergic reactions. Beside avoidance, there is currently no allergen-specific therapy available. Hypoallergenic variants of the major fish allergen, parvalbumin, for specific immunotherapy based on mutation of the 2 calcium-binding sites have been developed. This study sought to establish a mouse model of fish allergy resembling human disease and to investigate whether mouse and rabbit IgG antibodies induced by immunization with a hypoallergenic mutant of the major carp allergen protect against allergic symptoms in sensitized mice. C3H/HeJ mice were sensitized with recombinant wildtype Cyp c 1 or carp extract by intragastric gavage. Antibody, cellular immune responses, and epitope specificity in sensitized mice were investigated by ELISA, rat basophil leukemia assay, T-cell proliferation experiments using recombinant wildtype Cyp c 1, and overlapping peptides spanning the Cyp c 1 sequence. Anti-hypoallergenic Cyp c 1 mutant mouse and rabbit sera were tested for their ability to inhibit IgE recognition of Cyp c 1, Cyp c 1-specific basophil degranulation, and Cyp c 1-induced allergic symptoms in the mouse model. A mouse model of fish allergy mimicking human disease regarding IgE epitope recognition and symptoms as close as possible was established. Administration of antisera generated in mice and rabbits by immunization with a hypoallergenic Cyp c 1 mutant inhibited IgE binding to Cyp c 1, Cyp c 1-induced basophil degranulation, and allergic symptoms caused by allergen challenge in sensitized mice. Antibodies induced by immunization with a hypoallergenic Cyp c 1 mutant protect against allergic reactions in a murine model of fish allergy. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Asthma progression to airway remodeling and bone marrow eosinophil responses in genetically distinct strains of mice.

PubMed

Hogan, Mary Beth; Piktel, Debra; Hubbs, Ann F; McPherson, Leslie E; Landreth, Kenneth S

2008-12-01

Patient factors that cause long-term airway remodeling are largely unidentified. This suggests that genetic differences may determine which asthmatic patients develop airway remodeling. A murine model with repeated allergen exposure leading to peribronchial fibrosis in complement factor 5 (C5)-deficient A/J mice has been used to study asthma progression. No studies have addressed the systemic effects of allergen sensitization or chronic allergen exposure on bone marrow eosinophilopoiesis in this mouse strain. To investigate bone marrow eosinophil responses during acute sensitization and chronic allergen exposure using genetically distinct mouse strains differing in persistent airway reactivity and remodeling. The C5-sufficient BALB/c and C5-deficient A/J mice were repetitively exposed to intranasal ovalbumin for 12 weeks. Subsequently, the mice were evaluated for airway eosinophilia, mucus-containing goblet cells, and peribronchial fibrosis. Both strains of mice were also acutely sensitized to ovalbumin. Bone marrow eosinophil progenitor cells and mature eosinophils were enumerated. BALB/c and A/J mice have similar bone marrow responses after acute allergen exposure, with elevations in bone marrow eosinophil progenitor cell and eosinophil numbers. After chronic allergen exposure, only C5-deficient A/J mice that developed peribronchial fibrosis exhibited bone marrow eosinophilia. BALB/c mice lacked peribronchial fibrosis and extinguished accelerated eosinophil production after long-term allergen challenge. Chronic airway remodeling after repeated allergen exposure in genetically different mice correlated with differences in long-term bone marrow eosinophilopoiesis. Preventing asthma from progressing to chronic airway remodeling with fibrosis may involve identifying genetically determined influences on bone marrow responses to chronic allergen exposure.

Beneficial Effects of Prebiotic Saccharomyces cerevisiae Mannan on Allergic Asthma Mouse Models.

PubMed

Lew, D Betty; Michael, Christie F; Overbeck, Tracie; Robinson, W Scout; Rohman, Erin L; Lehman, Jeffrey M; Patel, Jennifer K; Eiseman, Brandi; LeMessurier, Kim S; Samarasinghe, Amali E; Gaber, M Waleed

2017-01-01

One of the unmet needs for asthma management is a new therapeutic agent with both anti-inflammatory and anti-smooth muscle (ASM) remodeling effects. The mannose receptor (MR) family plays an important role in allergen uptake and processing of major allergens Der p 1 and Fel d 1. We have previously reported that ASM cells express a mannose receptor (ASM-MR) and that mannan derived from Saccharomyces cerevisiae (SC-MN) inhibits mannosyl-rich lysosomal hydrolase-induced bovine ASM cell proliferation. Using a humanized transgenic mouse strain (huASM-MRC2) expressing the human MRC2 receptor in a SM tissue-specific manner, we have demonstrated that ASM hyperplasia/hypertrophy can occur as early as 15 days after allergen challenge in this mouse model and this phenomenon is preventable with SC-MN treatment. This proof-of-concept study would facilitate future development of a potential asthma therapeutic agent with dual function of anti-inflammatory and anti-smooth muscle remodeling effects.

Time-dependent distinct roles of Toll-like receptor 4 in a house dust mite-induced asthma mouse model.

PubMed

Ishii, T; Niikura, Y; Kurata, K; Muroi, M; Tanamoto, K; Nagase, T; Sakaguchi, M; Yamashita, N

2018-03-01

House dust mites (HDMs) are a common source of allergens that trigger both allergen-specific and innate immune responses in humans. Here, we examined the effect of allergen concentration and the involvement of Toll-like receptor 4 (TLR4) in the process of sensitization to house dust mite allergens in an HDM extract-induced asthma mouse model.　Intranasal administration of HDM extract induced an immunoglobulin E response and eosinophilic inflammation in a dose-dependent manner from 2.5 to 30 μg/dose. In TLR4-knockout mice, the infiltration of eosinophils and neutrophils into the lung was decreased compared with that in wild-type mice in the early phase of inflammation (total of three doses). However, in the late phase of inflammation (total of seven doses), eosinophil infiltration was significantly greater in TLR4-knockout mice than in wild-type mice. This suggests that the roles of TLR4 signaling are different between the early phase and the later phase of HDM allergen-induced inflammation. Thus, innate immune response through TLR4 regulated the response to HDM allergens, and the regulation was altered during the phase of inflammation. © 2018 The Foundation for the Scandinavian Journal of Immunology.

Mouse Sensitization and Exposure Are Associated with Asthma Severity in Urban Children.

PubMed

Grant, Torie; Aloe, Charles; Perzanowski, Matthew; Phipatanakul, Wanda; Bollinger, Mary E; Miller, Rachel; Matsui, Elizabeth C

Mouse sensitization and exposure are associated with uncontrolled asthma, but whether they are associated with asthma severity, an intrinsic disease characteristic and long-term outcome predictor, is unclear. To examine relationships between mouse sensitization and/or exposure and asthma severity in urban children. A total of 645 children (5-17 years) with uncontrolled asthma underwent mouse sensitization evaluation. Sensitized children had mouse allergen measured in bedroom dust. Relationships between mouse sensitization, allergen levels, and asthma severity measures (treatment step and Composite Asthma Severity Index [CASI]) were examined using regression models adjusted for age, sex, atopy, study site, race, ethnicity, and insurance. The study population was predominantly minority (69.6% black, 20.8% Hispanic), low income (61.8%), and mouse sensitized (54.4%). Mean ± SD treatment step was 3.2 ± 1.6, equivalent to medium-dose inhaled corticosteroid. Mean ± SD CASI was 6.5 ± 3.4, reflecting moderate persistent asthma. Mouse sensitization was associated with higher treatment step (3.5 vs 2.9, mouse-sensitized vs nonsensitized, P < .001), independent of potential confounders (β [95% CI], 0.36 [0.07-0.64]; P = .01). Mouse sensitization was associated independently with CASI (β [95% CI], 0.82 [0.16-1.47]; P = .02). Among mouse-sensitized participants, higher bedroom floor and bed Mus m 1 were independently associated with treatment step (β [95% CI], 0.26 [0.09-0.43]; P = .002 and β [95% CI], 0.22 [0.01-0.43]; P = .04), respectively. Higher bedroom floor Mus m 1 was independently associated with CASI (β [95% CI], 0.43 [0.05-0.81]; P = .03). Mouse sensitization and exposure are associated with asthma severity, among low-income, minority children. Further studies are needed to determine whether reducing allergen exposure among mouse-sensitized patients with asthma can reduce severity, ultimately altering childhood asthma natural history. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Protective effect of Bifidobacterium infantis CGMCC313-2 on ovalbumin-induced airway asthma and β-lactoglobulin-induced intestinal food allergy mouse models

PubMed Central

Liu, Meng-Yun; Yang, Zhen-Yu; Dai, Wen-Kui; Huang, Jian-Qiong; Li, Yin-Hu; Zhang, Juan; Qiu, Chuang-Zhao; Wei, Chun; Zhou, Qian; Sun, Xin; Feng, Xin; Li, Dong-Fang; Wang, He-Ping; Zheng, Yue-Jie

2017-01-01

AIM To determine whether oral administration of Bifidobacterium infantis CGMCC313-2 (B. infantis CGMCC313-2) inhibits allergen-induced airway inflammation and food allergies in a mouse model. METHODS Ovalbumin (OVA)-induced allergic asthma and β-lactoglobulin-induced food allergy mouse models were used in this study. Following oral administration of B. infantis CGMCC313-2 during or after allergen sensitization, histopathologic changes in the lung and intestine were evaluated by hematoxylin and eosin (HE) staining. In the allergic asthma mouse model, we evaluated the proportion of lung-infiltrating inflammatory cells. OVA-specific IgE and IgG1 levels in serum and cytokine levels in bronchoalveolar lavage fluid (BALF) were also assessed. In the food allergy mouse model, the levels of total IgE and cytokines in serum were measured. RESULTS Oral administration of B. infantis CGMCC313-2 during or after allergen sensitization suppressed allergic inflammation in lung and intestinal tissues, while the proportion of infiltrating inflammatory cells was significantly decreased in the BALF of allergic asthma mice. Moreover, B. infantis CGMCC313-2 decreased the serum levels of total IgE in food allergy mice, and reductions in IgE and IgG1 were also observed in OVA-induced allergic asthma mice. The expression of interleukin-4 (IL-4) and IL-13 in both serum and BALF was suppressed following the administration of B. infantis CGMCC313-2, while an effect on serum IL-10 levels was not observed. CONCLUSION B. infantis CGMCC313-2 inhibits the secretion of allergen-induced IgE, IL-4 and IL-13, and attenuates allergic inflammation. PMID:28405142

Outstanding animal studies in allergy II. From atopic barrier and microbiome to allergen-specific immunotherapy.

PubMed

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-06-01

Animal studies published within the past 18 months were assessed, focusing on innate and specific immunomodulation, providing knowledge of high translational relevance for human atopic and allergic diseases. Allergic companion animals represent alternative models, but most studies were done in mice. Atopic dermatitis mouse models were refined by the utilization of cytokines like IL-23 and relevant skin allergens or enzymes. A novel IL-6 reporter mouse allows biomonitoring of inflammation. Both skin pH and the (transferable) microflora have a pivotal role in modulating the skin barrier. The microflora of the gastrointestinal mucosa maintains tolerance to dietary compounds and can be disturbed by antiacid drugs. A key mouse study evidenced that dust from Amish households, but not from Hutterites protected mice against asthma. In studies on subcutaneous and sublingual allergen-specific immunotherapy, much focus was given on delivery and adjuvants, using poly-lacto-co-glycolic particles, CpGs, probiotics or Vitamin D3. The epicutaneous and intralymphatic routes showed promising results in mice and horses in terms of prophylactic and therapeutic allergy treatment. In atopic dermatitis, food allergies and asthma, environmental factors, together with the resident microflora and barrier status, decide on sensitization versus tolerance. Also allergen-specific immunotherapy operates with immunomodulatory principles.

Outstanding animal studies in allergy II. From atopic barrier and microbiome to allergen-specific immunotherapy

PubMed Central

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-01-01

Purpose of review Animal studies published within the past 18 months were assessed, focusing on innate and specific immunomodulation, providing knowledge of high translational relevance for human atopic and allergic diseases. Recent findings Allergic companion animals represent alternative models, but most studies were done in mice. Atopic dermatitis mouse models were refined by the utilization of cytokines like IL-23 and relevant skin allergens or enzymes. A novel IL-6 reporter mouse allows biomonitoring of inflammation. Both skin pH and the (transferable) microflora have a pivotal role in modulating the skin barrier. The microflora of the gastrointestinal mucosa maintains tolerance to dietary compounds and can be disturbed by antiacid drugs. A key mouse study evidenced that dust from Amish households, but not from Hutterites protected mice against asthma. In studies on subcutaneous and sublingual allergen-specific immunotherapy, much focus was given on delivery and adjuvants, using poly-lacto-co-glycolic particles, CpGs, probiotics or Vitamin D3. The epicutaneous and intralymphatic routes showed promising results in mice and horses in terms of prophylactic and therapeutic allergy treatment. Summary In atopic dermatitis, food allergies and asthma, environmental factors, together with the resident microflora and barrier status, decide on sensitization versus tolerance. Also allergen-specific immunotherapy operates with immunomodulatory principles. PMID:28375932

Activated glycoprotein A repetitions predominant (GARP)-expressing regulatory T cells inhibit allergen-induced intestinal inflammation in humanized mice.

PubMed

Eschborn, Melanie; Weigmann, Benno; Reissig, Sonja; Waisman, Ari; Saloga, Joachim; Bellinghausen, Iris

2015-07-01

Recently, we developed a humanized mouse model of allergen-induced IgE-dependent gut inflammation in PBMC-engrafted immunodeficient mice. In the present study, we wanted to investigate the role of regulatory T (Treg) cells and their activation status in this model. Nonobese diabetic-severe combined immunodeficiency-γc(-/-) mice were injected intraperitoneally with human PBMCs from allergic donors together with the respective allergen or NaCl as control in the presence or absence of different concentrations of CD4(+)CD25(+) Treg cells of the same donor. After an additional allergen boost 1 week later, mice were challenged with the allergen rectally on day 21 and gut inflammation was monitored by a high-resolution video mini-endoscopic system evaluating translucency, granularity, fibrin production, vascularity, and stool. Allergen-specific human IgE in mouse sera, which was detectable only in PBMC plus allergen-treated mice, was strongly inhibited by coinjection of Treg cells at a ratio of at least 1:10. Consequently, the presence of Treg cells significantly decreased IgE-dependent allergen-induced gut inflammation after rectal allergen challenge. In addition, Treg cells reduced allergen-specific proliferation and cytokine production of recovered human CD4(+) T cells in vitro. Activation of Treg cells before injection further increased all inhibitory effects. Prevention of gut inflammation also occurred by the administration of glycoprotein A repetitions predominant, a molecule expressed by activated Treg cells, whereas its blockade completely abrogated inhibition by Treg cells. These results demonstrate that allergen-specific gut inflammation in human PBMC-engrafted mice can be avoided by enhancing the numbers or activity of autologous Treg cells, which is of great interest for therapeutic intervention of allergic diseases of the intestine. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Allergen challenge-induced extravasation of plasma in mouse airways.

PubMed

Erjefält, J S; Andersson, P; Gustafsson, B; Korsgren, M; Sonmark, B; Persson, C G

1998-08-01

Mouse models are extensively used to study genetic and immunological mechanisms of potential importance to inflammatory airway diseases, e.g. asthma. However, the airway pathophysiology in allergic mice has received less attention. For example, plasma extravasation and the ensuing tissue-deposition of plasma proteins, which is a hallmark of inflammation, has not been examined in allergic mice. This study aims to examine the vascular permeability and the distribution of plasma proteins in mouse airways following exposure to allergen and serotonin. Extravasated plasma was quantified by a dual isotop technique using intravascular (131I-albumin) and extrasvascular (125I-albumin) plasma tracers. Histological visualization of fibrinogen and colloidal gold revealed the tissue distribution of extravasated plasma. Allergen aerosol exposure (3% OVA, 15min) of sensitized animals resulted in a marked plasma extravasation response in the trachea (P < 0.01) and the bronchi but not in the lung parenchyma. A similar extravasation response was induced by serotonin (P<0.001). Extravasating vessels (assessed by Monastral blue dye) were identified as intercartilaginous venules. Extravasated plasma abounded in the subepithelial tissue but was absent in the epithelium and airway lumen. The allergen-induced response was dose-dependently inhibited by iv administration of formoterol (P < 0.001), a vascular antipermeability agent. The present study demonstrates that serotonin and allergen challenge of sensitized mice increase airway venular permeability to cause transient extravasation and lamina propria distribution of plasma in the large airways. We suggest that the extravasation response is a useful measure of the intensity and the distribution of active inflammation

Determinants of Allergen Concentrations in Apartments of Asthmatic Children Living in Public Housing

PubMed Central

Levy, Jonathan I.; Rogers, Christine A.; Burge, Harriet A.; Spengler, John D.

2007-01-01

There is growing evidence linking poor housing conditions and respiratory diseases, including asthma. The association between housing conditions and asthma in the inner city has been attributed in part to cockroach and mouse infestation and the resulting allergen exposures. Multiple social and behavioral factors can influence environmental exposures and health conditions, necessitating a thorough examination of such factors. As part of the Healthy Public Housing Initiative, we evaluated the association between physical and household characteristics and pest-related allergen levels in three public housing developments in Boston, MA. We detected cockroach allergens (Bla g 1 and Bla g 2) in bedroom air, bed, and especially high concentrations in kitchen samples. In multivariate Tobit regressions controlling for development and season, clutter and lack of cleanliness in the apartment were associated with a tenfold increase in Bla g 1 concentration in the air, a sevenfold increase in Bla g 1 and an eightfold increase in Bla g 2 concentrations in the bed, and an 11-fold increase in Bla g 2 in the kitchen (p<0.05 for all). Holes in the wall/ceiling were associated with a six- to 11-fold increase in kitchen cockroach allergen concentrations (p<0.05). Occupancy in an apartment unit of 2 years or more was also associated with increased cockroach allergen concentrations. In contrast, there were low concentrations of mouse urinary protein in this population. In conclusion, these results suggest that interventions in these homes should focus on reducing cockroach allergen concentrations and that building-wide interventions should be supplemented with targeted efforts focused on high-risk units. PMID:17216349

Palmitoylethanolamide Supplementation during Sensitization Prevents Airway Allergic Symptoms in the Mouse

PubMed Central

Roviezzo, Fiorentina; Rossi, Antonietta; Caiazzo, Elisabetta; Orlando, Pierangelo; Riemma, Maria A.; Iacono, Valentina M.; Guarino, Andrea; Ialenti, Armando; Cicala, Carla; Peritore, Alessio; Capasso, Raffaele; Di Marzo, Vincenzo; Izzo, Angelo A.

2017-01-01

One important risk factor for the development of asthma is allergen sensitization. Recent increasing evidence suggests a prominent role of mast cells in asthma pathophysiology. Since Palmitoylethanolamide (PEA), an endogenous lipid mediator chemically related to – and co-released with- the endocannabinoid anandamide, behaves as a local autacoid down-regulator of mast cell activation and inflammation, we explored the possible contribution of PEA in allergic sensitization, by using ovalbumin (OVA) as sensitizing agent in the mouse. PEA levels were dramatically reduced in the bronchi of OVA-treated animals. This effect was coupled to a significant up-regulation of CB2 and GPR55 receptors, two of the proposed molecular PEA targets, in bronchi harvested from allergen-sensitized mice. PEA supplementation (10 mg/kg, 15 min before each allergen exposure) prevented OVA-induced bronchial hyperreactivity, but it did not affect IgE plasma increase. On the other hand, PEA abrogated allergen-induced cell recruitment as well as pulmonary inflammation. Evaluation of pulmonary sections evidenced a significant inhibitory action of PEA on pulmonary mast cell recruitment and degranulation, an effect coupled to a reduction of leukotriene C4 production. These findings demonstrate that allergen sensitization negatively affects PEA bronchial levels and suggest that its supplementation has the potential to prevent the development of asthma-like features. PMID:29311913

Isolation of Mal d 1 and Api g 1 - specific recombinant antibodies from mouse IgG Fab fragment libraries - Mal d 1-specific antibody exhibits cross-reactivity against Bet v 1.

PubMed

Haka, Jaana; Niemi, Merja H; Iljin, Kristiina; Reddy, Vanga Siva; Takkinen, Kristiina; Laukkanen, Marja-Leena

2015-05-27

Around 3-5% of the population suffer from IgE-mediated food allergies in Western countries and the number of food-allergenic people is increasing. Individuals with certain pollen allergies may also suffer from a sensitisation to proteins in the food products. As an example a person sensitised to the major birch pollen allergen, Bet v 1, is often sensitised to its homologues, such as the major allergens of apple, Mal d 1, and celery, Api g 1, as well. Development of tools for the reliable, sensitive and quick detection of allergens present in various food products is essential for allergic persons to prevent the consumption of substances causing mild and even life-threatening immune responses. The use of monoclonal antibodies would ensure the specific detection of the harmful food content for a sensitised person. Mouse IgG antibody libraries were constructed from immunised mice and specific recombinant antibodies for Mal d 1 and Api g 1 were isolated from the libraries by phage display. More detailed characterisation of the resulting antibodies was carried out using ELISA, SPR experiments and immunoprecipitation assays. The allergen-specific Fab fragments exhibited high affinity towards the target recombinant allergens. Furthermore, the Fab fragments also recognised native allergens from natural sources. Interestingly, isolated Mal d 1-specific antibody bound also to Bet v 1, the main allergen eliciting the cross-reactivity syndrome between the birch pollen and apple. Despite the similarities in Api g 1 and Bet v 1 tertiary structures, the isolated Api g 1-specific antibodies showed no cross-reactivity to Bet v 1. Here, high-affinity allergen-specific recombinant antibodies were isolated with interesting binding properties. With further development, these antibodies can be utilised as tools for the specific and reliable detection of allergens from different consumable products. This study gives new preliminary insights to elucidate the mechanism behind the pollen-food syndrome and to study the IgG epitope of the allergens.

An adjuvant free mouse model of oral allergenic sensitization to rice seeds protein

PubMed Central

2011-01-01

Background Rice is commonly known as a staple crop consumed worldwide, though with several rice proteins being reported for allergic properties in clinical studies. Thus, there is a growing need for the development of an animal model to better understand the allergenicity of rice proteins and the immunological and pathophysiological mechanisms underlying the development of food allergy. Methods Groups of BALB/c mice were sensitized daily with freshly homogenized rice flour (30 mg or 80 mg) without adjuvant by intragastric gavage. In addition, the mice were challenged with extracted rice flour proteins at several time points intragastrically. Hypersensitivity symptoms in mice were evaluated according to a scoring system. Vascular leakage, ELISA of rice protein-specific IgE, histopathology of small intestine, and passive cutaneous anaphylaxis were conducted on challenged mice. Results An adjuvant free mouse model of rice allergy was established with sensitized mice showing increased scratching behaviors and increased vascular permeability. Rice protein-specific IgE was detected after eighteen days of sensitization and from the fifth challenge onwards. Inflammatory damage to the epithelium in the small intestine of mice was observed beyond one month of sensitization. Passive cutaneous anaphylaxis results confirmed the positive rice allergy in the mouse model. Conclusions We introduced a BALB/c mouse model of rice allergy with simple oral sensitization without the use of adjuvant. This model would serve as a useful tool for further analysis on the immunopathogenic mechanisms of the various rice allergens, for the evaluation of the hypersensitivity of rice or other cereal grains, and to serve as a platform for the development of immunotherapies against rice allergens. PMID:21605393

Allergenicity, immunogenicity and dose-relationship of three intact allergen vaccines and four allergoid vaccines for subcutaneous grass pollen immunotherapy.

PubMed

Henmar, H; Lund, G; Lund, L; Petersen, A; Würtzen, P A

2008-09-01

Different vaccines containing intact allergens or chemically modified allergoids as active ingredients are commercially available for specific immunotherapy. Allergoids are claimed to have decreased allergenicity without loss of immunogenicity and this is stated to allow administration of high allergoid doses. We compared the allergenicity and immunogenicity of four commercially available chemically modified grass pollen allergoid products with three commercially available intact grass pollen allergen vaccines. The allergenicity was investigated with immunoglobulin (Ig)E-inhibition and basophil activation assays. Human T cell proliferation and specific IgG-titres following mouse immunizations were used to address immunogenicity. Furthermore, intact allergen vaccines with different contents of active ingredients were selected to study the influence of the allergen dose. In general, a lower allergenicity for allergen vaccines was clearly linked to a reduced immunogenicity. Compared with the vaccine with the highest amount of intact allergen, the allergoids caused reduced basophil activation as well as diminished immunogenicity demonstrated by reduced T cell activation and/or reduced induction of murine grass-specific IgG antibodies. Interestingly, intact allergen vaccines with lower content of active ingredient exhibited similarly reduced allergenicity, while immunogenicity was still higher or equal to that of allergoids. The low allergenicity observed for some allergoids was inherently linked to a significantly lower immunogenic response questioning the rationale behind the chemical modification into allergoids. In addition, the linkage between allergenicity, immunogenicity and dose found for intact allergen vaccines and the immunogen as well as allergenic immune responses observed for allergoids suggest that the modified allergen vaccines do not contain high doses of immunologically active ingredients.

Aeroallergens in dairy barns near Cooperstown, New York and Rochester, Minnesota

DOE Office of Scientific and Technical Information (OSTI.GOV)

Campbell, A.R.; Swanson, M.C.; Fernandez-Caldas, E.

1989-08-01

We sampled atmospheric barn air using a volumetric air sampler in ten barns near Cooperstown, NY and six barns near Rochester, MN, and, with radioimmunoassays, measured allergens of Aspergillus fumigatus, Thermoactinomyces vulgaris, Micropolyspori faeni, short ragweed, rye grass group I pollen, Alternaria (Alt-1), Dermatophagoides sp. Lepidoglyphus destructor, common insect allergen, mouse urine, rat urine, and cattle epithelium. The most abundant allergen present was A. fumigatus followed by L. destructor. This study provides initial data on barn aerobiology and demonstrates for the first time the abundance of L. destructor allergens in North American dairy barns. More comprehensive study of barns, poultrymore » houses, confinement houses for swine, and other agricultural environments from various geographic locations is needed to define the allergen levels to which millions of farm workers are exposed each day. While most of the allergens were expected, the presence of airborne allergens reactive with antisera to Dermatophagoides suggests indirectly that substantial amounts of pyroglyphid mites are present in some barns.« less

Allergen sensitization linked to climate and age, not to intermittent-persistent rhinitis in a cross-sectional cohort study in the (sub)tropics.

PubMed

Larenas-Linnemann, Désirée; Michels, Alexandra; Dinger, Hanna; Shah-Hosseini, Kijawasch; Mösges, Ralph; Arias-Cruz, Alfredo; Ambriz-Moreno, Marichuy; Barajas, Martín Bedolla; Javier, Ruth Cerino; de la Luz Cid Del Prado, María; Moreno, Manuel Alejandro Cruz; Almaráz, Roberto García; García-Cobas, Cecilia Y; Garcia Imperial, Daniel A; Muñoz, Rosa Garcia; Hernández-Colín, Dante; Linares-Zapien, Francisco J; Luna-Pech, Jorge A; Matta-Campos, Juan J; Jiménez, Norma Martinez; Medina-Ávalos, Miguel A; Hernández, Alejandra Medina; Maldonado, Alberto Monteverde; López, Doris N; Pizano Nazara, Luis J; Sanchez, Emmanuel Ramirez; Ramos-López, José D; Rodríguez-Pérez, Noel; Rodríguez-Ortiz, Pablo G

2014-01-01

Allergen exposure leads to allergen sensitization in susceptible individuals and this might influence allergic rhinitis (AR) phenotype expression. We investigated whether sensitization patterns vary in a country with subtropical and tropical regions and if sensitization patterns relate to AR phenotypes or age. In a national, cross-sectional study AR patients (2-70 y) seen by allergists underwent blinded skin prick testing with a panel of 18 allergens and completed a validated questionnaire on AR phenotypes. 628 patients were recruited. The major sensitizing allergen was house dust mite (HDM) (56%), followed by Bermuda grass (26%), ash (24%), oak (23%) and mesquite (21%) pollen, cat (22%) and cockroach (21%). Patients living in the tropical region were almost exclusively sensitized to HDM (87%). In the central agricultural zones sensitization is primarily to grass and tree pollen. Nationwide, most study subjects had perennial (82.2%), intermittent (56.5%) and moderate-severe (84.7%) AR. Sensitization was not related to the intermittent-persistent AR classification or to AR severity; seasonal AR was associated with tree (p < 0.05) and grass pollen sensitization (p < 0.01). HDM sensitization was more frequent in children (0-11 y) and adolescents (12-17 y) (subtropical region: p < 0.0005; tropical region p < 0.05), but pollen sensitization becomes more important in the adult patients visiting allergists (Adults vs children + adolescents for tree pollen: p < 0.0001, weeds: p < 0.0005). In a country with (sub)tropical climate zones SPT sensitization patterns varied according to climatological zones; they were different from those found in Europe, HDM sensitization far outweighing pollen allergies and Bermuda grass and Ash pollen being the main grass and tree allergens, respectively. Pollen sensitization was related to SAR, but no relation between sensitization and intermittent-persistent AR or AR severity could be detected. Sensitization patterns vary with age (child HDM, adult pollen). Clinical implications of our findings are dual: only a few allergens -some region specific- cover the majority of sensitizations in (sub)tropical climate zones. This is of major importance for allergen manufacturers and immunotherapy planning. Secondly, patient selection in clinical trials should be based on the intermittent-persistent and severity classifications, rather than on the seasonal-perennial AR subtypes, especially when conducted in (sub)tropical countries.

Allergen sensitization linked to climate and age, not to intermittent-persistent rhinitis in a cross-sectional cohort study in the (sub)tropics

PubMed Central

2014-01-01

Background Allergen exposure leads to allergen sensitization in susceptible individuals and this might influence allergic rhinitis (AR) phenotype expression. We investigated whether sensitization patterns vary in a country with subtropical and tropical regions and if sensitization patterns relate to AR phenotypes or age. Methods In a national, cross-sectional study AR patients (2-70 y) seen by allergists underwent blinded skin prick testing with a panel of 18 allergens and completed a validated questionnaire on AR phenotypes. Results 628 patients were recruited. The major sensitizing allergen was house dust mite (HDM) (56%), followed by Bermuda grass (26%), ash (24%), oak (23%) and mesquite (21%) pollen, cat (22%) and cockroach (21%). Patients living in the tropical region were almost exclusively sensitized to HDM (87%). In the central agricultural zones sensitization is primarily to grass and tree pollen. Nationwide, most study subjects had perennial (82.2%), intermittent (56.5%) and moderate-severe (84.7%) AR. Sensitization was not related to the intermittent-persistent AR classification or to AR severity; seasonal AR was associated with tree (p < 0.05) and grass pollen sensitization (p < 0.01). HDM sensitization was more frequent in children (0-11 y) and adolescents (12-17 y) (subtropical region: p < 0.0005; tropical region p < 0.05), but pollen sensitization becomes more important in the adult patients visiting allergists (Adults vs children + adolescents for tree pollen: p < 0.0001, weeds: p < 0.0005). Conclusions In a country with (sub)tropical climate zones SPT sensitization patterns varied according to climatological zones; they were different from those found in Europe, HDM sensitization far outweighing pollen allergies and Bermuda grass and Ash pollen being the main grass and tree allergens, respectively. Pollen sensitization was related to SAR, but no relation between sensitization and intermittent-persistent AR or AR severity could be detected. Sensitization patterns vary with age (child HDM, adult pollen). Clinical implications of our findings are dual: only a few allergens –some region specific- cover the majority of sensitizations in (sub)tropical climate zones. This is of major importance for allergen manufacturers and immunotherapy planning. Secondly, patient selection in clinical trials should be based on the intermittent-persistent and severity classifications, rather than on the seasonal-perennial AR subtypes, especially when conducted in (sub)tropical countries. PMID:24976949

Outstanding animal studies in allergy I. From asthma to food allergy and anaphylaxis.

PubMed

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-06-01

Animal models published within the past 18 months on asthma, food allergy and anaphylaxis, all conditions of rising public health concern, were reviewed. While domestic animals spontaneously develop asthma, food allergy and anaphylaxis, in animal models, divergent sensitization and challenge routes, dosages, intervals and antigens are used to induce asthmatic, food allergic or anaphylactic phenotypes. This must be considered in the interpretation of results. Instead of model antigens, gradually relevant allergens such as house dust mite in asthma, and food allergens like peanut, apple and peach in food allergy research were used. Novel engineered mouse models such as a mouse with a T-cell receptor for house dust mite allergen Der p 1, or with transgenic human hFcγR genes, facilitated the investigation of single molecules of interest. Whole-body plethysmography has become a state-of-the-art in-vivo readout in asthma research. In food allergy and anaphylaxis research, novel techniques were developed allowing real-time monitoring of in-vivo effects following allergen challenge. Networks to share tissues were established as an effort to reduce animal experiments in allergy which cannot be replaced by in-vitro measures. Natural and artificial animal models were used to explore the pathophysiology of asthma, food allergy and anaphylaxis and to improve prophylactic and therapeutic measures. Especially the novel mouse models mimicking molecular aspects of the complex immune network in asthma, food allergy and anaphylaxis will facilitate proof-of-concept studies under controlled conditions.

Outstanding animal studies in allergy I. From asthma to food allergy and anaphylaxis

PubMed Central

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-01-01

Purpose of review Animal models published within the past 18 months on asthma, food allergy and anaphylaxis, all conditions of rising public health concern, were reviewed. Recent findings While domestic animals spontaneously develop asthma, food allergy and anaphylaxis, in animal models, divergent sensitization and challenge routes, dosages, intervals and antigens are used to induce asthmatic, food allergic or anaphylactic phenotypes. This must be considered in the interpretation of results. Instead of model antigens, gradually relevant allergens such as house dust mite in asthma, and food allergens like peanut, apple and peach in food allergy research were used. Novel engineered mouse models such as a mouse with a T-cell receptor for house dust mite allergen Der p 1, or with transgenic human hFcγR genes, facilitated the investigation of single molecules of interest. Whole-body plethysmography has become a state-of-the-art in-vivo readout in asthma research. In food allergy and anaphylaxis research, novel techniques were developed allowing real-time monitoring of in-vivo effects following allergen challenge. Networks to share tissues were established as an effort to reduce animal experiments in allergy which cannot be replaced by in-vitro measures. Summary Natural and artificial animal models were used to explore the pathophysiology of asthma, food allergy and anaphylaxis and to improve prophylactic and therapeutic measures. Especially the novel mouse models mimicking molecular aspects of the complex immune network in asthma, food allergy and anaphylaxis will facilitate proof-of-concept studies under controlled conditions. PMID:28346234

Allergen-Specific Immunotherapy with Monomeric Allergoid in a Mouse Model of Atopic Dermatitis

PubMed Central

Babakhin, Alexander; Andreev, Sergey; Nikonova, Alexandra; Shilovsky, Igor; Buzuk, Andrey; Elisyutina, Olga; Fedenko, Elena; Khaitov, Musa

2015-01-01

Atopic dermatitis (AD) is a widespread and difficult to treat allergic skin disease and is a tough challenge for healthcare. In this study, we investigated whether allergen-specific immunotherapy (ASIT) with a monomeric allergoid obtained by succinylation of ovalbumin (sOVA) is effective in a mouse model of atopic dermatitis. An experimental model of AD was reproduced by epicutaneous sensitization with ovalbumin (OVA). ASIT was performed with subcutaneous (SC) administration of increasing doses of OVA or sOVA. The levels of anti-OVA antibodies, as well as cytokines, were detected by ELISA. Skin samples from patch areas were taken for histologic examination. ASIT with either OVA or sOVA resulted in a reduction of both the anti-OVA IgE level and the IgG1/IgG2a ratio. Moreover, ASIT with sOVA increased the IFN-γ level in supernatants after splenocyte stimulation with OVA. Histologic analysis of skin samples from the sites of allergen application showed that ASIT improved the histologic picture by decreasing allergic inflammation in comparison with untreated mice. These data suggest that ASIT with a succinylated allergen represents promising approach for the treatment of AD. PMID:26275152

Peptide immunotherapy in allergic asthma generates IL-10–dependent immunological tolerance associated with linked epitope suppression

PubMed Central

Campbell, John D.; Buckland, Karen F.; McMillan, Sarah J.; Kearley, Jennifer; Oldfield, William L.G.; Stern, Lawrence J.; Grönlund, Hans; van Hage, Marianne; Reynolds, Catherine J.; Boyton, Rosemary J.; Cobbold, Stephen P.; Kay, A. Barry; Altmann, Daniel M.; Larché, Mark

2009-01-01

Treatment of patients with allergic asthma using low doses of peptides containing T cell epitopes from Fel d 1, the major cat allergen, reduces allergic sensitization and improves surrogate markers of disease. Here, we demonstrate a key immunological mechanism, linked epitope suppression, associated with this therapeutic effect. Treatment with selected epitopes from a single allergen resulted in suppression of responses to other (“linked”) epitopes within the same molecule. This phenomenon was induced after peptide immunotherapy in human asthmatic subjects and in a novel HLA-DR1 transgenic mouse model of asthma. Tracking of allergen-specific T cells using DR1 tetramers determined that suppression was associated with the induction of interleukin (IL)-10+ T cells that were more abundant than T cells specific for the single-treatment peptide and was reversed by anti–IL-10 receptor administration. Resolution of airway pathophysiology in this model was associated with reduced recruitment, proliferation, and effector function of allergen-specific Th2 cells. Our results provide, for the first time, in vivo evidence of linked epitope suppression and IL-10 induction in both human allergic disease and a mouse model designed to closely mimic peptide therapy in humans. PMID:19528258

Allergenicity, immunogenicity and dose-relationship of three intact allergen vaccines and four allergoid vaccines for subcutaneous grass pollen immunotherapy

PubMed Central

Henmar, H; Lund, G; Lund, L; Petersen, A; Würtzen, P A

2008-01-01

Different vaccines containing intact allergens or chemically modified allergoids as active ingredients are commercially available for specific immunotherapy. Allergoids are claimed to have decreased allergenicity without loss of immunogenicity and this is stated to allow administration of high allergoid doses. We compared the allergenicity and immunogenicity of four commercially available chemically modified grass pollen allergoid products with three commercially available intact grass pollen allergen vaccines. The allergenicity was investigated with immunoglobulin (Ig)E-inhibition and basophil activation assays. Human T cell proliferation and specific IgG-titres following mouse immunizations were used to address immunogenicity. Furthermore, intact allergen vaccines with different contents of active ingredients were selected to study the influence of the allergen dose. In general, a lower allergenicity for allergen vaccines was clearly linked to a reduced immunogenicity. Compared with the vaccine with the highest amount of intact allergen, the allergoids caused reduced basophil activation as well as diminished immunogenicity demonstrated by reduced T cell activation and/or reduced induction of murine grass-specific IgG antibodies. Interestingly, intact allergen vaccines with lower content of active ingredient exhibited similarly reduced allergenicity, while immunogenicity was still higher or equal to that of allergoids. The low allergenicity observed for some allergoids was inherently linked to a significantly lower immunogenic response questioning the rationale behind the chemical modification into allergoids. In addition, the linkage between allergenicity, immunogenicity and dose found for intact allergen vaccines and the immunogen as well as allergenic immune responses observed for allergoids suggest that the modified allergen vaccines do not contain high doses of immunologically active ingredients. PMID:18647321

TRIMELLITIC ANHYDRIDE-INDUCED EOSINOPHILLA IN A MOUSE MODEL OF OCCUPATIONAL ASTHMA

EPA Science Inventory

Trimellitic anhydride (TMA) is a low molecular weight chemical known to cause occupational asthma. The present study was designed to determine if TMA could elicit eosinophil infiltration into the lung of a sensitized mouse similarly to previous studies with the protein allergen ...

Indoor determinants of dustborne allergens in Mexican homes

PubMed Central

Hernández-Cadena, Leticia; Zeldin, Darryl C.; Sever, Michelle L.; Sly, Peter D.; London, Stephanie J.; Escamilla-Nuñez, María Consuelo; Romieu, Isabelle

2015-01-01

Exposure to indoor allergens represents a significant risk factor for allergies and asthma in several parts of the world. In Mexico, few studies have evaluated indoor allergens, including cat, dog, and mouse allergens and the factors that predict their presence. This study evaluates the main environmental and household predictors of high prenatal allergen levels and multiple allergen exposures in a birth cohort from Mexico City. A cross-sectional study was conducted as part of a birth cohort study of 1094 infants recruited during pregnancy and followed until delivery. We collected dust samples in a subset of 264 homes and assessed environmental factors. Der p 1, Der f 1, dust mite group 2, Fel d 1, Can f 1, Rat n 1, Mus m 1, and Bla g 2 concentrations in dust samples were measured using immunoassays. To define detectable allergen levels, the lowest limits of detection for each allergen were taken as cutoff points. Overall allergen exposure was considered high when four or more allergens exceeded detectable levels in the same household. Logistic regression was used for predictive models. Eighty-five percent of homes had at least one allergen in dust over the detection limit, 52.1% had high exposure (four or more allergens above detectable limits), and 11.7% of homes had detectable levels for more than eight allergens. Der p 1, Der p 2, Mus m 1, and Fel d 1 were the most frequent allergens detected. Each allergen had both common and distinct predictors. The main predictors of a high multiple allergen index were the size of the home, pesticide use, mother's age, mother as homemaker, and season. Increased indoor environmental allergen exposure is mainly related to sociodemographic factors and household cleaning. PMID:25715241

Comparison of allergenicity and immunogenicity of an intact allergen vaccine and commercially available allergoid products for birch pollen immunotherapy.

PubMed

Lund, L; Henmar, H; Würtzen, P A; Lund, G; Hjortskov, N; Larsen, J N

2007-04-01

Specific immunotherapy with intact allergen vaccine is a well-documented treatment for allergic diseases. Different vaccine formulations are currently commercially available, the active ingredient either being intact allergens or chemically modified allergoids. The rationale behind allergoids is to decrease allergenicity while maintaining immunogenicity. However, data from the German health authorities based on reporting of adverse events over a 10-year period did not indicate increased safety of allergoids over intact allergens. The objective of this study was to investigate the effect of chemical modification on allergenicity and immunogenicity comparing four commercial allergoid products for birch pollen immunotherapy with an intact allergen vaccine. Solid-phase IgE inhibition and histamine release assays were selected as model systems for allergenicity, and a combination of human T cell proliferation and IgG titres following mouse immunizations were used to address the immunogenicity of the intact allergen vaccine and the four allergoids. In all assays, the products were normalized with respect to the manufacturer's recommended maintenance dose. IgE inhibition experiments showed a change in epitope composition comparing intact allergen vaccine with allergoid. One allergoid product induced enhanced histamine release compared to the intact allergens, while the other three allergoids showed reduced release. Standard T cell stimulation assays using lines from allergic patients showed a reduced response for all allergoids compared with the intact allergen vaccine regardless of the cell type used for antigen presentation. All allergoids showed reduced capacity to induce allergen-specific IgG responses in mice. While some allergoids were associated with reduced allergenicity, a clear reduction in immunogenicity was observed for all allergoid products compared with the intact allergen vaccine, and the commercial allergoids tested therefore do not fulfil the allergoid concept.

Effectiveness of an Integrated Pest Management Intervention in Controlling Cockroaches, Mice, and Allergens in New York City Public Housing

PubMed Central

Kass, Daniel; McKelvey, Wendy; Carlton, Elizabeth; Hernandez, Marta; Chew, Ginger; Nagle, Sean; Garfinkel, Robin; Clarke, Brian; Tiven, Julius; Espino, Christian; Evans, David

2009-01-01

Background Cockroaches and mice, which are common in urban homes, are sources of allergens capable of triggering asthma symptoms. Traditional pest control involves the use of scheduled applications of pesticides by professionals as well as pesticide use by residents. In contrast, integrated pest management (IPM) involves sanitation, building maintenance, and limited use of least toxic pesticides. Objectives We implemented and evaluated IPM compared with traditional practice for its impact on pests, allergens, pesticide use, and resident satisfaction in a large urban public housing authority. Methods We assigned IPM or control status to 13 buildings in five housing developments, and evaluated conditions at baseline, 3 months, and 6 months in 280 apartments in Brooklyn and Manhattan, in New York City (New York). We measured cockroach and mouse populations, collected cockroach and mouse urinary protein allergens in dust, and interviewed residents. All statistical models controlled for baseline levels of pests or allergens. Results Compared with controls, apartments receiving IPM had significantly lower counts of cockroaches at 3 months and greater success in reducing or sustaining low counts of cockroaches at both 3 and 6 months. IPM was associated with lower cockroach allergen levels in kitchens at 3 months and in beds and kitchens at 6 months. Pesticide use was reduced in IPM relative to control apartments. Residents of IPM apartments also rated building services more positively. Conclusions In contrast to previous IPM studies, which involved extensive cleaning, repeat visits, and often extensive resident education, we found that an easily replicable single IPM visit was more effective than the regular application of pesticides alone in managing pests and their consequences. PMID:19672400

Allergens and β-Glucans in Dutch Homes and Schools: Characterizing Airborne Levels

PubMed Central

Krop, Esmeralda J. M.; Jacobs, José H.; Sander, Ingrid; Raulf-Heimsoth, Monika; Heederik, Dick J. J.

2014-01-01

Background Indoor air quality has an effect on respiratory health. Children are more vulnerable to a decreased indoor air quality as their lungs are still developing. We measured levels of allergens and β-(1,3)-glucans in 19 school buildings and determined whether measured levels could be reproduced. School levels were compared to those in 169 homes and the effect of building characteristics on both home and school exposure was explored. Methods Electrostatic Dust fall Collectors were placed in school buildings for 8 weeks and in homes for 2 weeks to collect settled airborne dust. Cat, dog, and mouse allergen levels, domestic mite antigen levels and β-(1,3)-glucans were measured in the extracts from the collectors. Results were corrected for sampling duration. Using questionnaire data, relations between measured levels and building and classroom characteristics were explored. Results In schools, exposure levels were highest in classrooms and were influenced by the socioeconomic status of the children, the season measurements were performed, moisture status of the building and pet ownership. Repeated measurements in different seasons and over the years showed significantly different levels. Home exposure was influenced by socioeconomic status, occupancy and pet ownership. Domestic mite antigen was found in higher levels in extracts from homes compared to schools while pet allergen levels were 13 times higher in schools compared to homes without pets. For mouse allergen overall levels of exposure were low but still two times higher in schools compared to homes. Levels of β-(1,3)-glucans were also approximately two times higher in schools than in homes. Conclusion Exposure levels of several allergens and β-(1,3)-glucans in schools differ over time and are higher than in homes. For children, exposure levels measured at school could contribute to their total exposure as especially animal allergen levels can be much higher in schools compared to homes. PMID:24551183

Chemical modification of birch allergen extract leads to a reduction in allergenicity as well as immunogenicity.

PubMed

Würtzen, Peter Adler; Lund, Lise; Lund, Gitte; Holm, Jens; Millner, Anders; Henmar, Helene

2007-01-01

In Europe, specific immunotherapy is currently conducted with vaccines containing allergen preparations based on intact extracts. In addition to this, chemically modified allergen extracts (allergoids) are used for specific allergy treatment. Reduced allergenicity and thereby reduced risk of side effects in combination with retained ability to activate T cells and induce protective allergen-specific antibody responses has been claimed for allergoids. In the current study, we compared intact allergen extracts and allergoids with respect to allergenicity and immunogenicity. The immunological response to birch allergen extract, alum-adsorbed extract, birch allergoid and alum-adsorbed allergoid was investigated in vitro in human basophil histamine release assay and by stimulation of human allergen-specific T cell lines. In vivo, Bet v 1-specific IgG titers in mice were determined after repetitive immunizations. In all patients tested (n = 8), allergoid stimulations led to reduced histamine release compared to the intact allergen extract. However, the allergoid preparations were not recognized by Bet v 1-specific T cell lines (n = 7), which responded strongly to the intact allergen extract. Mouse immunizations showed a clearly reduced IgG induction by allergoids and a strongly potentiating effect of the alum adjuvant. Optimal IgG titers were obtained after 3 immunizations with intact allergen extracts, while 5 immunizations were needed to obtain maximal response to the allergoid. The reduced histamine release observed for allergoid preparations may be at the expense of immunological efficacy because the chemical modifications lead to a clear reduction in T cell activation and the ability to induce allergen-specific IgG antibody responses. Copyright 2007 S. Karger AG, Basel.

Respiratory allergen from house dust mite is present in human milk and primes for allergic sensitization in a mouse model of asthma.

PubMed

Macchiaverni, P; Rekima, A; Turfkruyer, M; Mascarell, L; Airouche, S; Moingeon, P; Adel-Patient, K; Condino-Neto, A; Annesi-Maesano, I; Prescott, S L; Tulic, M K; Verhasselt, V

2014-03-01

There is an urgent need to identify environmental risk and protective factors in early life for the prevention of allergy. Our study demonstrates the presence of respiratory allergen from house dust mite, Der p 1, in human breast milk. Der p 1 in milk is immunoreactive, present in similar amounts as dietary egg antigen, and can be found in breast milk from diverse regions of the world. In a mouse model of asthma, oral exposure to Der p through breast milk strongly promotes sensitization rather than protect the progeny as we reported with egg antigen. These data highlight that antigen administration to the neonate through the oral route may contribute to child allergic sensitization and have important implications for the design of studies assessing early oral antigen exposure for allergic disease prevention. The up-to-now unknown worldwide presence of respiratory allergen in maternal milk allows new interpretation and design of environmental control epidemiological studies for allergic disease prevention. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Characterization of allergoids from ovalbumin in vitro and in vivo.

PubMed

Salgado, J; Casadevall, G; Puigneró, V; Queralt, J

1996-01-01

Several in vivo and in vitro methods for monitoring immunological properties of two allergoids obtained by formaldehyde treatment of ovalbumin (OA) were developed. The calculated molecular weight of allergoids was 80 kD (OA-F1) and 165 kD (OA-F2), respectively. The allergenic activity in vitro of allergoids in mast-cell histamine release assay was 1000 times lower than of OA. Both allergoids showed reduced ability to induce passive cutaneous anaphylaxis in the Sprague-Dawley rats or systemic anaphylaxis in Dunkin-Harley guinea-pigs. The ability of OA and allergoids to bind to the OA-specific IgE antibodies was measured in vivo by the inhibition of passive cutaneous anaphylaxis (PCA-inhibition). Allergoid binding to IgE was 51-66% lower than the native allergen. Moreover, the avidity of OA-specific IgG antibodies, measured by ELISA-inhibition, for allergoids and allergen was of the same order. Allergoids induced a different pattern of humoral immune response from that, induced by the native allergen. Thus, after immunization of BALB/c mouse, both allergoids induced a higher production of IgG and a lower production of IgE than OA, only OA-F2 induced a lower production of IgG1. The differences in the IgA response to the immunogens was not significant. Delayed hypersensitivity studies in the BALB/c mouse showed that allergoids were 5- to 12-times less effective in inducing a cell-mediated immune response than OA. The present study provides a battery of immunological methods for preclinical testing of modified allergens.

Food-cooking processes modulate allergenic properties of hen's egg white proteins.

PubMed

Liu, Xiaoyu; Feng, Bai-Sui; Kong, Xiaoli; Xu, Hong; Li, Xiumin; Yang, Ping-Chang; Liu, Zhigang

2013-01-01

Reducing the allergenicity of food allergens can suppress the clinical symptoms of food allergy. The objective of the present study was to investigate the effects of processing on the allergenic properties of hen's egg white proteins. Eggs were processed by traditional Chinese cooking, including steaming, water boiling, frying, spicing and tea boiling. The contents of processed egg protein were assessed by sodium dodecyl sulfate polyacrylamide gel electrophoresis; the allergenicity was evaluated by Western blotting, enzyme-linked immunosorbent assay and enzyme allergosorbent test inhibition. Circular dichroism spectrum analysis of four major egg allergens from various egg products was performed as well. A mouse model of food allergy was developed to test the allergenicity of processed egg protein in vivo. Protein degradation was significant following tea boiling and spiced-tea boiling. The total allergenic potential of water-boiled egg and fried egg was relatively higher than that of steamed egg, spiced egg and tea-boiled egg. Challenge with proteins from raw egg, water-boiled egg and fried egg induced skewed T-helper 2 pattern responses (Th2 responses) in the intestine of mice sensitized to egg proteins; however, when the mice sensitized to egg proteins were challenged with proteins from steamed egg, spiced egg and tea-boiled egg, respectively, only weak Th2 responses were induced in their intestine. Processing by steaming, spicing, or tea boiling can weaken the allergenicity of egg proteins. Copyright © 2012 S. Karger AG, Basel.

Cell Therapy for Prophylactic Tolerance in Immunoglobulin E-mediated Allergy.

PubMed

Baranyi, Ulrike; Farkas, Andreas M; Hock, Karin; Mahr, Benedikt; Linhart, Birgit; Gattringer, Martina; Focke-Tejkl, Margit; Petersen, Arnd; Wrba, Fritz; Rülicke, Thomas; Valenta, Rudolf; Wekerle, Thomas

2016-05-01

Therapeutic strategies for the prophylaxis of IgE-mediated allergy remain an unmet medical need. Cell therapy is an emerging approach with high potential for preventing and treating immunological diseases. We aimed to develop a cell-based therapy inducing permanent allergen-specific immunological tolerance for preventing IgE-mediated allergy. Wild-type mice were treated with allergen-expressing bone marrow cells under a short course of tolerogenic immunosuppression (mTOR inhibition and costimulation blockade). Bone marrow was retrieved from a novel transgenic mouse ubiquitously expressing the major grass pollen allergen Phl p 5 as a membrane-anchored protein (BALB/c-Tg[Phlp5-GFP], here mPhl p 5). After transplantation recipients were IgE-sensitized at multiple time points with Phl p 5 and control allergen. Mice treated with mPhl p 5 bone marrow did not develop Phl p 5-specific IgE (or other isotypes) despite repeated administration of the allergen, while mounting and maintaining a strong humoral response towards the control allergen. Notably, Phl p 5-specific T cell responses and allergic airway inflammation were also completely prevented. Interestingly allergen-specific B cell tolerance was maintained independent of Treg functions indicating deletional tolerance as underlying mechanism. This proof-of-concept study demonstrates that allergen-specific immunological tolerance preventing occurrence of allergy can be established through a cell-based therapy employing allergen-expressing leukocytes. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Topically applied ZnO nanoparticles suppress allergen induced skin inflammation but induce vigorous IgE production in the atopic dermatitis mouse model

PubMed Central

2014-01-01

Background Metal oxide nanoparticles such as ZnO are used in sunscreens as they improve their optical properties against the UV-light that causes dermal damage and skin cancer. However, the hazardous properties of the particles used as UV-filters in the sunscreens and applied to the skin have remained uncharacterized. Methods Here we investigated whether different sized ZnO particles would be able to penetrate injured skin and injured allergic skin in the mouse atopic dermatitis model after repeated topical application of ZnO particles. Nano-sized ZnO (nZnO) and bulk-sized ZnO (bZnO) were applied to mechanically damaged mouse skin with or without allergen/superantigen sensitization. Allergen/superantigen sensitization evokes local inflammation and allergy in the skin and is used as a disease model of atopic dermatitis (AD). Results Our results demonstrate that only nZnO is able to reach into the deep layers of the allergic skin whereas bZnO stays in the upper layers of both damaged and allergic skin. In addition, both types of particles diminish the local skin inflammation induced in the mouse model of AD; however, nZnO has a higher potential to suppress the local effects. In addition, especially nZnO induces systemic production of IgE antibodies, evidence of allergy promoting adjuvant properties for topically applied nZnO. Conclusions These results provide new hazard characterization data about the metal oxide nanoparticles commonly used in cosmetic products and provide new insights into the dermal exposure and hazard assessment of these materials in injured skin. PMID:25123235

Letter to the Editor: Can dog allergen immunotherapy reduce concomitant allergic sensitization to other furry animals? A preliminary experience.

PubMed

Liccardi, G; Calzetta, L; Salzillo, A; Billeri, L; Lucà, G; Rogliani, P

2017-03-01

It has been shown that allergen immunotherapy (AIT) is effective in reducing symptoms of allergic asthma and rhinitis. Data on the efficacy are less convincing with regard to AIT for allergens of common pets (cats/dogs). We describe a case of dog allergy in which we explored if dog AIT (DAI) could reduce a concomitant allergic sensitization to other allergens of furry animals. Our case demonstrates the efficacy of sublingual DAI on SPTs, symptom score, and spirometric responses despite persistent exposure to dog allergens at home in a patient sensitized, but not exposed, to several other furry animals. Moreover, this is the first report suggesting that DAI is able to reduce SPTs responses not only to dog, but also to other furry animals such as rabbit, horse, mouse, rat, hamster, cow. We recommend an accurate anamnesis and diagnosis of dog allergy before prescribing DAI. In particular, the use of ImmunoCAP ISAC is essential to verify the presence of IgE to lipocalins / albumins belonging to other furry animals. Obviously further studies carried out by using different DAI schedules, allergen amount and time of re-evaluation, laboratory procedure should be performed to confirm our findings.

Allergenic proteins are fragmented in low concentrations of sodium hypochlorite.

PubMed

Chen, P; Eggleston, P A

2001-07-01

To facilitate allergen removal from indoor environments, it would be helpful to have household cleaning products that modified allergenic activity. Because NaOCl dissolves proteins in high concentrations and is both capable of killing bacteria and viruses and inactivating viral antigens at somewhat lower concentrations, we explored its effects on Mus m 1 and other indoor allergens. To examine the ability of NaOCl to reduce the allergenicity of Mus m 1 and other indoor allergens. Using purified mouse urinary allergen, we examined the effect on protein measured by Coomassie protein assay and on Mus m 1 measured by ELISA. We also examined the effects using SDS/PAGE and Western blots probed with sheep anti-Mus m 1 and with allergic human serum. When NaOCl and Mus m 1 were combined in a molar ratio of 100 : 1, IgE binding to Mus m 1 on Western blot was significantly reduced. At higher NaOCl concentrations the protein appeared to fragment and eventually became undetectable. Fragmentation appeared to be random in that peptides of a wide range of apparent molecular weight were produced. The reaction was complete within 1-2 min at OCl : pr ratios of greater than 200 : 1 and was optimal at pH 7.4. Immunological activity of other allergens (Fel d 1, Bla g 1, Der p 1) was decreased in vitro and dried allergen extracts were removed from surfaces. Adding an extraneous protein, BSA, to NaOCl:Mus m 1 solutions decreased the effect of NaOCl on the allergen. We concluded that NaOCl at concentrations commonly used in household products is capable of dramatically affecting allergenic protein.

A plasmacytoid dendritic cell (CD123+/CD11c-) based assay system to predict contact allergenicity of chemicals

PubMed Central

Ayehunie, Seyoum; Snell, Maureen; Child, Matthew; Klausner, Mitchell

2009-01-01

A predictive allergenicity test system for assessing the contact allergenicity of chemicals is needed by the cosmetic and pharmaceutical industry to monitor product safety in the marketplace. Development of such non-animal alternative assay systems for skin sensitization and hazard identification has been pursued by policy makers and regulatory agencies. We investigated whether phenotypic and functional changes to a subset of dendritic cells (DC), plasmacytoid DC (pDC), could be used to identify contact allergens. To achieve this goal, normal human DC were generated from CD34+ progenitor cells and cryopreserved. Frozen DC were thawed and the pDC fraction (CD123+/CD11c-) was harvested using FACS sorting. The pDC were cultured, expanded, and exposed to chemical allergens (N=26) or non-allergens (N=22). Concentrations of each chemical that resulted in >50% viability was determined using FACS analysis of propidium iodide stained cells using pDC from 2-5 donors. Expression of the surface marker, CD86, which has been implicated in dendritic cell maturation, was used as a marker of allergenicity. CD86 expression increased (≥ 1.5 fold) for 25 of 26 allergens (sensitivity = 96%) but did not increase for 19 of 22 non-allergens (specificity = 86%). In a direct comparison to historical data for the regulatory approved, mouse local lymph node assay (LLNA) for 23 allergens and 22 non-allergens, the pDC method had sensitivity and specificity of 96% and 86%, respectively, while the sensitivity and specificity of the LLNA assay was 83% and 82%, respectively. In conclusion, CD86 expression in pDC appears to be a sensitive and specific indicator to identify contact allergenicity. Such an assay method utilizing normal human cells will be useful for high throughput screening of chemicals for allergenicity. PMID:19665512

Exposure to triclosan augments the allergic response to ovalbumin in a mouse model of asthma.

PubMed

Anderson, Stacey E; Franko, Jennifer; Kashon, Michael L; Anderson, Katie L; Hubbs, Ann F; Lukomska, Ewa; Meade, B Jean

2013-03-01

During the last decade, there has been a remarkable and unexplained increase in the prevalence of asthma. These studies were conducted to investigate the role of dermal exposure to triclosan, an endocrine-disrupting compound, on the hypersensitivity response to ovalbumin (OVA) in a murine model of asthma. Triclosan has had widespread use in the general population as an antibacterial and antifungal agent and is commonly found in consumer products such as soaps, deodorants, toothpastes, shaving creams, mouthwashes, and cleaning supplies. For these studies, BALB/c mice were exposed dermally to concentrations of triclosan ranging from 0.75 to 3% (0.375-1.5mg/mouse/day) for 28 consecutive days. Concordantly, mice were ip injected with OVA (0.9 µg) and aluminum hydroxide (0.5mg) on days 1 and 10 and challenged with OVA (125 µg) by pharyngeal aspiration on days 19 and 27. Compared with the animals exposed to OVA alone, increased spleen weights, OVA-specific IgE, interleukin-13 cytokine levels, and numbers of lung eosinophils were demonstrated when mice were coexposed to OVA and triclosan. Statistically significant increases in OVA-specific and nonspecific airway hyperreactivity were observed for all triclosan coexposed groups compared with the vehicle and OVA controls. In these studies, exposure to triclosan alone was not demonstrated to be allergenic; however, coexposure with a known allergen resulted in enhancement of the hypersensitivity response to that allergen, suggesting that triclosan exposure may augment the allergic responses to other environmental allergens.

Sensitizing capacity and allergenicity of enzymatically cross-linked sodium caseinate in comparison to sodium caseinate in a mouse model for cow's milk allergy.

PubMed

van Esch, Betty C A M; Gros-van Hest, Marjan; Westerbeek, Hans; Garssen, Johan

2013-03-27

A transglutaminase cross-linked caseinate was designed for use in dairy products to increase the viscosity of food matrices. The difference in structure of cross-linked caseinate might have implications for the risk of developing cow's milk allergy. The sensitizing capacity and the allergenicity (the potency to induce an allergic effector response) of cross-linked sodium caseinate was investigated using a mouse model for cow's milk allergy. Mice were orally sensitized with cross-linked caseinate or caseinate using cholera toxin as adjuvant. Anaphylactic shock reactions, change in body temperature, acute allergic skin response, caseinate-, cross-linked caseinate-IgE and mMCP-1 concentrations were determined after challenge with cross-linked caseinate or caseinate. Sensitization with cross-linked caseinate did not result in anaphylactic shock symptoms, drop in body temperature or release of serum mMCP-1. A tendency toward decreased casein-specific IgE levels was observed. The allergenicity did not differ between both products. These results indicate that in already caseinate-sensitized mice, cross-linked caseinate did not provoke more pronounced allergenic reactions compared to sodium caseinate. On top of that, reduced sensitization to cross-linked caseinate was observed. Cross-linked caseinate might therefore be an interesting new dietary concept for humans at risk for food allergy although more mechanistic studies and clinical trials are needed for validation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Immunotherapeutic efficacy of liposome-encapsulated refined allergen vaccines against Dermatophagoides pteronyssinus allergy.

PubMed

Chaisri, Urai; Tungtrongchitr, Anchalee; Indrawattana, Nitaya; Meechan, Panisara; Phurttikul, Watchara; Tasaniyananda, Natt; Saelim, Nawannaporn; Chaicumpa, Wanpen; Sookrung, Nitat

2017-01-01

Allergen specific immunotherapy (AIT) can modulate the allergic response causing a long-term symptom subsidence/abolishment which leads to reduced drug use and prevention of new sensitization. AIT of house dust mite allergy (HDM) using the mite crude extract (CE) as the therapeutic agent is not only less effective than the AIT for many other allergens, but also frequently causes adverse effects during the treatment course. In this study, mouse model of Dermatophagoides pteronyssinus (Dp) allergy was invented for testing therapeutic efficacies of intranasally administered liposome (L) encapsulated vaccines made of single Dp major allergens (L-Der p 1, L-Der p 2), combined allergens (L-Der p 1 and Der p 2), and crude Dp extract (L-CE). The allergen sparing intranasal route was chosen as it is known that the effective cells induced at the nasal-associated lymphoid tissue can exert their activities at the lower respiratory tissue due to the common mucosal traffic. Liposome was chosen as the vaccine delivery vehicle and adjuvant as the micelles could reduce toxicity of the entrapped cargo. The Dp-CE allergic mice received eight doses of individual vaccines/placebo on alternate days. All vaccine formulations caused reduction of the Th2 response of the Dp allergic mice. However, only the vaccines made of single refined allergens induced expressions of immunosuppressive cytokines (TGF-β, IL-35 and/or IL-10) which are the imperative signatures of successful AIT. The data emphasize the superior therapeutic efficacy of single refined major allergen vaccines than the crude allergenic extract vaccine.

Quantification of Fel d 1 in house dust samples of cat allergic patients by using monoclonal antibody specific to a novel IgE-binding epitope.

PubMed

Tasaniyananda, Natt; Tungtrongchitr, Anchalee; Seesuay, Watee; Sakolvaree, Yuwaporn; Aiumurai, Pisinee; Indrawattana, Nitaya; Chaicumpa, Wanpen; Sookrung, Nitat

2018-03-01

Avoidance of allergen exposure is an effective measure for preventing naÏve and allergic individuals from sensitization (primary intervention) and disease aggravation (secondary intervention), respectively. Regular monitoring of the allergens in the environment is required for the effective intervention. Thus, there is a need for cost-effective test kits for environmental allergen quantifications. To invent a test kit for quantification of cat major allergen, Fel d 1. A mouse monoclonal antibody (MAb) specific to the newly identified IgE-binding conformational epitope of the cat major allergen (Fel d 1) and rabbit polyclonal IgG to recombinant Fel d 1 were used as allergen capture and detection reagents, respectively. Native Fel d 1 was used in constructing a standard curve. Sixteen of 36 dust samples collected from houses of cat allergic subjects in Bangkok contained Fel d 1 above 0.29 μg/gram of dust which is considered as a novel threshold level for causing cat allergy sensitization or symptoms. Among them, 7 samples contained the allergen exceeding 2.35 μg/gram of dust which is the level that would aggravate asthma. Results of the allergen quantification using the locally made test kit showed strong correlation (r = 0.923) with the allergen quantification using commercialized reagents. The assay using MAb to Fel d 1 IgE-binding epitope of this study has potential application as an economic and practical tool for cat allergy intervention measure especially in localities where health resources are relatively limited.

Early life exposure to bisphenol A investigated in mouse models of airway allergy, food allergy and oral tolerance.

PubMed

Nygaard, Unni Cecilie; Vinje, Nina Eriksen; Samuelsen, Mari; Andreassen, Monica; Groeng, Else-Carin; Bølling, Anette Kocbach; Becher, Rune; Lovik, Martinus; Bodin, Johanna

2015-09-01

The impact of early life exposure to bisphenol A (BPA) through drinking water was investigated in mouse models of respiratory allergy, food allergy and oral tolerance. Balb/c mice were exposed to BPA (0, 10 or 100 μg/ml), and the offspring were intranasally exposed to the allergen ovalbumin (OVA). C3H/HeJ offspring were sensitized with the food allergen lupin by intragastric gavage, after exposure to BPA (0, 1, 10 or 100 μg/ml). In separate offspring, oral tolerance was induced by gavage of 5 mg lupin one week before entering the protocol for the food allergy induction. In the airway allergy model, BPA (100 μg/ml) caused increased eosinophil numbers in bronchoalveolar lavage fluid (BALF) and a trend of increased OVA-specific IgE levels. In the food allergy and tolerance models, BPA did not alter the clinical anaphylaxis or antibody responses, but induced alterations in splenocyte cytokines and decreased mouse mast cell protease (MMCP)-1 serum levels. In conclusion, early life exposure to BPA through drinking water modestly augmented allergic responses in a mouse model of airway allergy only at high doses, and not in mouse models for food allergy and tolerance. Thus, our data do not support that BPA promotes allergy development at exposure levels relevant for humans. Copyright © 2015 Elsevier Ltd. All rights reserved.

Glove-derived foreign proteins induce allergen-specific IgE in a mouse model.

PubMed

Busch, Marion; Schröder, Claudia; Baron, Jens-Malte; Ott, Hagen; Bruckner, Thomas; Diepgen, Thomas L; Mahler, Vera

2008-04-01

Currently, most medical gloves are produced with a low content of natural rubber latex (NRL) protein. However, they may be substituted by proteins of foreign origin to maintain specific properties of the material. The aim of this study was to investigate the allergenicity and immunogenicity of unexpected proteins (i.e., soy and casein) compared with NRL proteins in a murine model in BALB/c mice. All respective allergen sources (extracts from three brands of NRL gloves, soy, and casein) were able to induce significant allergen-specific IgE and IgG(1) responses. On average, the highest IgE induction occurred after immunization with NRL, followed by soy and casein. Certain individuals from each treatment group exhibited levels of specific IgE as high as due to NRL. To analyze further specific IgE responses on a single allergen level, we established a microarray based on recombinant allergens for allergen-specific murine IgE detection. Besides specific IgE against rHev b 3, -6, -7, -8, and -11, specific IgE against kappa-casein could be detected in mice immunized with NRL glove extract, indicating a sensitization potential of the contained foreign protein. The substitution of genuine latex proteins by proteins of foreign origin may lead to a shift and de novo increase in sensitization to the finished products.

Aryl Hydrocarbon Receptor Protects Lungs from Cockroach Allergen-Induced Inflammation by Modulating Mesenchymal Stem Cells.

PubMed

Xu, Ting; Zhou, Yufeng; Qiu, Lipeng; Do, Danh C; Zhao, Yilin; Cui, Zhuang; Wang, Heng; Liu, Xiaopeng; Saradna, Arjun; Cao, Xu; Wan, Mei; Gao, Peisong

2015-12-15

Exposure to cockroach allergen leads to allergic sensitization and increased risk of developing asthma. Aryl hydrocarbon receptor (AhR), a receptor for many common environmental contaminants, can sense not only environmental pollutants but also microbial insults. Mesenchymal stem cells (MSCs) are multipotent progenitor cells with the capacity to modulate immune responses. In this study, we investigated whether AhR can sense cockroach allergens and modulate allergen-induced lung inflammation through MSCs. We found that cockroach allergen-treated AhR-deficient (AhR(-/-)) mice showed exacerbation of lung inflammation when compared with wild-type (WT) mice. In contrast, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an AhR agonist, significantly suppressed allergen-induced mouse lung inflammation. MSCs were significantly reduced in cockroach allergen-challenged AhR(-/-) mice as compared with WT mice, but increased in cockroach allergen-challenged WT mice when treated with TCDD. Moreover, MSCs express AhR, and AhR signaling can be activated by cockroach allergen with increased expression of its downstream genes cyp1a1 and cyp1b1. Furthermore, we tracked the migration of i.v.-injected GFP(+) MSCs and found that cockroach allergen-challenged AhR(-/-) mice displayed less migration of MSCs to the lungs compared with WT. The AhR-mediated MSC migration was further verified by an in vitro Transwell migration assay. Epithelial conditioned medium prepared from cockroach extract-challenged epithelial cells significantly induced MSC migration, which was further enhanced by TCDD. The administration of MSCs significantly attenuated cockroach allergen-induced inflammation, which was abolished by TGF-β1-neutralizing Ab. These results suggest that AhR plays an important role in protecting lungs from allergen-induced inflammation by modulating MSC recruitment and their immune-suppressive activity. Copyright © 2015 by The American Association of Immunologists, Inc.

Type I allergy to elderberry (Sambucus nigra) is elicited by a 33.2 kDa allergen with significant homology to ribosomal inactivating proteins.

PubMed

Förster-Waldl, E; Marchetti, M; Schöll, I; Focke, M; Radauer, C; Kinaciyan, T; Nentwich, I; Jäger, S; Schmid, E R; Boltz-Nitulescu, G; Scheiner, O; Jensen-Jarolim, E

2003-12-01

Patients suffering from allergic rhinoconjunctivitis and dyspnoea during summer may exhibit these symptoms after contact with flowers or dietary products of the elderberry tree Sambucus nigra. Patients with a history of summer hayfever were tested in a routine setting for sensitization to elderberry. Nine patients having allergic symptoms due to elderberry and specific sensitization were investigated in detail. We studied the responsible allergens in extracts from elderberry pollen, flowers and berries, and investigated cross-reactivity with allergens from birch, grass and mugwort. Sera from patients were tested for IgE reactivity to elderberry proteins by one-dimensional (1D) and 2D electrophoresis/immunoblotting. Inhibition studies with defined allergens and elderberry-specific antibodies were used to evaluate cross-reactivity. The main elderberry allergen was purified by gel filtration and reversed-phase HPLC, and subjected to mass spectrometry. The in-gel-digested allergen was analysed by the MS/MS sequence analysis and peptide mapping. The N-terminal sequence of the predominant allergen was analysed. 0.6% of 3668 randomly tested patients showed positive skin prick test and/or RAST to elderberry. IgE in patients' sera detected a predominant allergen of 33.2 kDa in extracts from elderberry pollen, flowers and berries, with an isoelectric point at pH 7.0. Pre-incubation of sera with extracts from birch, mugwort or grass pollen rendered insignificant or no inhibition of IgE binding to blotted elderberry proteins. Specific mouse antisera reacted exclusively with proteins from elderberry. N-terminal sequence analysis, as well as MS/MS spectrometry of the purified elderberry allergen, indicated homology with ribosomal inactivating proteins (RIPs). We present evidence that the elderberry plant S. nigra harbours allergenic potency. Independent methodologies argue for a significant homology of the predominant 33.2 kDa elderberry allergen with homology to RIPs. We conclude that this protein is a candidate for a major elderberry allergen with designation Sam n 1.

1H, 13C and 15N resonance assignments and second structure information of Fag s 1: Fagales allergen from Fagus sylvatica

PubMed Central

Moraes, A. H.; Asam, C.; Batista, A.; Almeida, F. C. L.; Wallner, M.; Ferreira, F.; Valente, A. P.

2017-01-01

Fagales allergens belonging to the Bet v 1 family account responsible for the majority of spring pollinosis in the temperate climate zones in the Northern hemisphere. Among them, Fag s 1 from beech pollen is an important trigger of Fagales pollen associated allergic reactions. The protein shares high similarity with birch pollen Bet v 1, the best-characterized member of this allergen family. Of note, recent work on Bet v 1 and its homologues found in Fagales pollen demonstrated that not all allergenic members of this family have the capacity to induce allergic sensitization. Fag s 1 was shown to bind pre-existing IgE antibodies most likely primarily directed against other members of this multi-allergen family. Therefore, it is especially interesting to compare the structures of Bet v 1-like pollen allergens, which have the potential to induce allergic sensitization with allergens that are mainly cross-reactive. This in the end will help to identify allergy eliciting molecular pattern on Bet v 1-like allergens. In this work, we report the 1H, 15N and 13C NMR assignment of beech pollen Fag s 1 as well as the secondary structure information based on backbone chemical shifts. PMID:26289775

Allergens in household dust and serological indicators of atopy and sensitization in Detroit children with history-based evidence of asthma.

PubMed

Williams, Ann Houston; Smith, James Travis; Hudgens, Edward E; Rhoney, Scott; Ozkaynak, Halûk; Hamilton, Robert G; Gallagher, Jane E

2011-09-01

Home exposure to allergens is an important factor in the development of sensitization and subsequent exacerbations of allergic asthma. We investigated linkages among allergen exposure, immunological measurements, and asthma by examining (1) reservoir dust allergen levels in homes, (2) associations between presence of allergens in homes and sensitization status of resident children, and (3) associations between asthma status and total IgE, atopy (by Phadiatop), and positive allergen-specific tests. The study protocol was approved by Institutional Review Boards (IRBs) of the University of North Carolina Chapel Hill; Westat, Inc.; and the US Environmental Protection Agency Human Research Protocol Office. Data were collected from questionnaires, serum analyses, and household vacuum dust. Children (n = 205) were predominately African American (AA) (85.4%) and 51.6% were asthmatic. Sera from 185 children and home dust samples (n = 141) were analyzed for total and specific IgE antibodies to allergens from cat and dog dander, cockroach, dust mites, mice, rats, and molds. Sixty percent of the homes had detectable levels of three or more dust allergens. The proportions of children with positive allergen-specific IgE tests were dust mite (32%), dog (28%), cat (23%), cockroach (18%), mouse (5%), rat (4%), and molds (24-36%). Children testing positive to a single allergen also had positive responses to other allergens. Those children with positive serum tests for cat, dog, and dust mite lived in homes with detectable levels of cat (51%), dog (90%), and dust mite (Der f 1) (92%) allergens. Correlations between children's specific IgE levels and dust levels were linearly related for dog (p < .04), but not for cat (p = .12) or dust mite (Der f 1) (p = .21). Odds ratios (95% CI) for the associations between asthma and serum-specific IgE were over 1.0 for cat, dog, dust mite (Der f 1), cockroach, and four types of molds. House dust allergen exposure levels, however, exhibited no differences between asthmatic and non-asthmatic homes. Both the co-occurrence of multiple allergens in dust and the high frequency of multiple allergen sensitizations indicate that a broad-based intervention aimed at reducing multiple allergens (pets, pests, and molds) would be more successful than any approach that aimed at reducing one type of allergen.

Urinary Peptides As a Novel Source of T Cell Allergen Epitopes

PubMed Central

da Silva Antunes, Ricardo; Pham, John; McMurtrey, Curtis; Hildebrand, William H.; Phillips, Elizabeth; Mallal, Simon; Sidney, John; Busse, Paula; Peters, Bjoern; Schulten, Véronique; Sette, Alessandro

2018-01-01

Mouse allergy in both laboratory workers and in inner-city children is associated with allergic rhinitis and asthma, posing a serious public health concern. Urine is a major source of mouse allergens, as mice spray urine onto their surroundings, where the proteins dry up and become airborne on dust particles. Here, we tested whether oligopeptides that are abundant in mouse urine may contribute to mouse allergic T cell response. Over 1,300 distinct oligopeptides were detected by mass spectrometry analysis of the low molecular weight filtrate fraction of mouse urine (LoMo). Posttranslationally modified peptides were common, accounting for almost half of total peptides. A pool consisting of 225 unique oligopeptides of 13 residues or more in size identified within was tested for its capacity to elicit T cell reactivity in mouse allergic donors. Following 14-day in vitro stimulation of PBMCs, we detected responses in about 95% of donors tested, directed against 116 distinct peptides, predominantly associated with Th2 cytokines (IL-5). Peptides from non-urine related proteins such as epidermal growth factor, collagen, and Beta-globin accounted for the highest response (15.9, 9.1, and 8.1% of the total response, respectively). Peptides derived from major urinary proteins (MUPs), kidney androgen-regulated protein (KAP), and uromodulin were the main T cell targets from kidney or urine related sources. Further ex vivo analysis of enrichment of 4-1BB expressing cells demonstrated that LoMo pool-specific T cell reactivity can be detected directly ex vivo in mouse allergic but not in non-allergic donors. Further cytometric analysis of responding cells revealed a bone fide memory T cell phenotype and confirmed their Th2 polarization. Overall, these data suggest that mouse urine-derived oligopeptides are a novel target for mouse allergy-associated T cell responses, which may contribute to immunopathological mechanisms in mouse allergy. PMID:29755469

A method for measuring mouse respiratory allergic reaction to low-dose chemical exposure to allergens: an environmental chemical of uncertain allergenicity, a typical contact allergen and a non-sensitizing irritant.

PubMed

Fukuyama, Tomoki; Tajima, Yukari; Ueda, Hideo; Hayashi, Koichi; Shutoh, Yasufumi; Harada, Takanori; Kosaka, Tadashi

2010-05-19

Our aim was to improve a method for detecting respiratory hypersensitivity by testing three confirmed respiratory allergens (trimellitic anhydride [TMA], phthalic anhydride [PA] and toluene diisocyanate [TDI]), an environmental chemical of uncertain allergenicity (2,4-d-butyl [DB]), a confirmed contact allergen (2,4-dinitrochlorobenzene [DNCB]) and a standard irritant (sodium dodecyl sulfate [SDS]). BALB/c mice were topically sensitized (nine times in 3 weeks) with these chemicals, then challenged via the trachea. One day post-challenge, samples were taken from the mice to assay for total immunoglobulin (IgE and IgG(1)) levels in serum and bronchoalveolar lavage fluid (BALF); differential cell counts and cytokine/chemokine levels in BALF; lymphocyte counts and surface antigen expression on B-cells within lung-associated lymph nodes (LNs); ex situ cytokine production by cells from these LNs; and gene expression in BALF (CCR3) and LNs (CCR4, STAT6 and GATA-3). The three confirmed respiratory allergens and DB induced immune response characteristic of immediate-type respiratory reactions, as evidenced by increased total IgE and IgG(1) levels; influx of eosinophils, neutrophils, chemokines and cytokines in BALF; increased surface antigen expression on B-cells in LNs; increased Th2 cytokine production in LNs; and increased respiratory allergy-related gene expression in both BALF and LNs. In contrast, DNCB and SDS treatments yielded, at most, insignificant increases in all respiratory allergic parameters. Thus, the protocol was equally suitable for use with an environmental chemical of unknown allergenicity and for typical respiratory allergens. Since the protocol differentiated respiratory allergens from contact allergens and irritants, it may be useful for detecting respiratory allergy related to environmental chemicals. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Role of breast milk in a mouse model of maternal transmission of asthma susceptibility.

PubMed

Leme, Adriana S; Hubeau, Cedric; Xiang, Yuhong; Goldman, Alejandra; Hamada, Kaoru; Suzaki, Yasue; Kobzik, Lester

2006-01-15

Epidemiologic data suggest a link between nursing by asthmatic mothers and increased risk of allergy in babies. We sought to experimentally test the potential contribution of breast milk mediator(s) in a mouse model of maternal transmission of asthma risk by evaluating the effect of adoptive nursing on asthma susceptibility in the offspring. We measured airway hyperresponsiveness (AHR) and allergic airway inflammation (AI) after an intentionally suboptimal OVA Ag sensitization, tested the allergen independence of the maternal effect by using a second allergen, casein, for sensitization of the baby mice, and tested the potential role of cytokines by measuring their levels in breast milk. Offspring of asthmatic, but not normal, mothers showed AHR and AI, indicating a maternal transfer of asthma risk. After adoptive nursing, both groups (litters born to asthmatic mothers and nursed by normal mothers, and normal babies nursed by asthmatic mothers) showed AHR (enhanced pause after methacholine aerosol, 50 mg/ml, 3.7 +/- 0.7, 4.2 +/- 0.5, respectively, vs 1.1 +/- 0.1 normal controls, n = 25, p < 0.01) and AI, seen as eosinophilia on histology and bronchoalveolar lavage (40.7 +/- 4.5%, 28.7 +/- 3.7%, vs 1.0 +/- 0.5% normals, n = 25, p < 0.01) after OVA sensitization. Similar results using casein allergen were observed. Multiplex assays for cytokines (IFN-gamma, IL-2, IL-4, IL-5, TNF-alpha, and IL-13) in breast milk were negative. Breast milk is sufficient, but not necessary, to mediate allergen-independent maternal transmission of asthma risk to offspring.

Exposure to Triclosan Augments the Allergic Response to Ovalbumin in a Mouse Model of Asthma

PubMed Central

Anderson, Stacey E.; Franko, Jennifer; Kashon, Michael L.; Anderson, Katie L.; Hubbs, Ann F.; Lukomska, Ewa; Meade, B. Jean

2015-01-01

During the last decade, there has been a remarkable and unexplained increase in the prevalence of asthma. These studies were conducted to investigate the role of dermal exposure to triclosan, an endocrine-disrupting compound, on the hypersensitivity response to ovalbumin (OVA) in a murine model of asthma. Triclosan has had widespread use in the general population as an antibacterial and antifungal agent and is commonly found in consumer products such as soaps, deodorants, toothpastes, shaving creams, mouthwashes, and cleaning supplies. For these studies, BALB/c mice were exposed dermally to concentrations of triclosan ranging from 0.75 to 3% (0.375–1.5 mg/mouse/day) for 28 consecutive days. Concordantly, mice were ip injected with OVA (0.9 μg) and aluminum hydroxide (0.5 mg) on days 1 and 10 and challenged with OVA (125 μg) by pharyngeal aspiration on days 19 and 27. Compared with the animals exposed to OVA alone, increased spleen weights, OVA-specific IgE, interleukin-13 cytokine levels, and numbers of lung eosinophils were demonstrated when mice were coexposed to OVA and triclosan. Statistically significant increases in OVA-specific and nonspecific airway hyperreactivity were observed for all triclosan coexposed groups compared with the vehicle and OVA controls. In these studies, exposure to triclosan alone was not demonstrated to be allergenic; however, coexposure with a known allergen resulted in enhancement of the hypersensitivity response to that allergen, suggesting that triclosan exposure may augment the allergic responses to other environmental allergens. PMID:23192912

Antacid medication inhibits digestion of dietary proteins and causes food allergy: a fish allergy model in BALB/c mice.

PubMed

Untersmayr, Eva; Schöll, Isabella; Swoboda, Ines; Beil, Waltraud J; Förster-Waldl, Elisabeth; Walter, Franziska; Riemer, Angelika; Kraml, Georg; Kinaciyan, Tamar; Spitzauer, Susanne; Boltz-Nitulescu, George; Scheiner, Otto; Jensen-Jarolim, Erika

2003-09-01

Digestible proteins were supposed to be irrelevant for oral sensitization and induction of food allergy. Approximately 10% of the adult population uses antacids for the treatment of dyspeptic disorders, drugs that hinder peptic digestion. In these patients, proteins that are normally degradable might act as food allergens. We aimed to study the influence of antacid intake on the allergenicity of dietary proteins, taking sturgeon caviar and parvalbumin, the major fish allergen, as examples. Caviar proteins and recombinant parvalbumin from carp, rCyp c 1, were applied for intragastric feedings with or without the antacids sucralfate, ranitidine or omeprazole, using a Balb/c mouse model. Both caviar proteins and parvalbumin were rapidly degraded in an in vitro digestion assay at pH 2.0, but not at pH 5.0, imitating the effect of antacids. The groups fed with caviar in combination with ranitidine hydrochloride intramuscularly or sucralfate orally had significant levels of caviar-specific IgE antibodies (P <.01), T-cell reactivity, and elevated counts of gastrointestinal eosinophils and mast cells. Food allergy in these groups was further evidenced by oral provocation tests and positive immediate-type skin reactivity. In contrast, feedings with caviar alone led to antigen-specific T-cell tolerance. None of the groups showed immune reactivity against the daily mouse diet. As a proof of the principle, feeding mice with parvalbumin in combination with ranitidine or omeprazole intramuscularly induced allergen-specific IgE antibodies (P <.05). When antacid medication impairs the gastric digestion, IgE synthesis toward novel dietary proteins is promoted, leading to food allergy.

A clinical study of airborne allergens in the United Arab Emirates.

PubMed

Lestringant, G G; Bener, A; Frossard, P M; Abdulkhalik, S; Bouix, G

1999-10-01

In the past 25 years the United Arab Emirates (UAE) have experienced a socioeconomic boom. The once nomadic Bedouin population of Al Ain, in the emirate of Abu Dhabi, now lives in modern air-conditioned accommodation, and huge desalination plants have allowed afforestation and farming. To evidence responsible airborne allergens in an UAE population. 263 UAE Nationals who attended Tawam Hospital (Al Ain, UAE) with a respiratory disease suspected of being of allergic origin, were submitted to SPT and RAST. The choice of pollinic allergens was made in accordance with the local flora and market availability. All patients were SPTed with at least the same battery of 15 pollinic and indoor allergens. Most patients were submitted to at least 4 RAST, viz Cynodon dactylon, Salsola kali, Prosopis juliflora and Dermatophagoides pteronyssinus. 71.8% patients were positive for at least one allergen. Pollen accounted for 61.6% of positive patients, with 45.2% positive to chenopodiaceae, 33% to gramineae and 23.5% to P. juliflora. Indoor allergens were positive in 30.4% of patients with 17.9% positive to D. pteronyssinus and D. farinae, 11% to Blatella germanica, 8.3% to Cat fur, 4.9% to Goat hair, 0.7% to Rat hair and Mouse hair and 1.5% to Candida albicans. Pollen was the prominent allergen. There is room, however, for further epidemiological studies possibly with new extracts and RAST specifically designed after the species of the Gulf region.

Risk factors associated with airway allergic diseases from exposure to laboratory animal allergens among veterinarians.

PubMed

Krakowiak, Anna; Wiszniewska, Marta; Krawczyk, Patrycja; Szulc, Bogdan; Wittczak, Tomasz; Walusiak, Jolanta; Pałczynski, Cezary

2007-05-01

Investigate the risk factors for the development of occupational airway allergy (OAA) from exposure to laboratory animal allergens (LAA) among Polish veterinarians. Two hundred veterinarians responded to the questionnaire and were subjected to skin prick test (SPT) to common allergens and LAA (rat, mouse, hamster, guinea pig, rabbit). Evaluation of total serum IgE level and specific IgE against occupational allergens was performed. In addition, bronchial hyperreactivity (BHR) and peak expiratory flow rate (PEFR) were measured before and after specific challenge testing (SCT) only in the subjects with work-related symptoms suggestive of occupational asthma (OA). The prevalence of asthmatic and ocular symptoms was statistically more prevalent in the group of veterinarians sensitised to LAA versus non-sensitised subjects. The most frequent occupational allergens of skin and serum reactivity were LAA (44.5 and 31.5%, respectively). In 41 (20.5%) and in 22 (11%) subjects out of 200 veterinarians, serum specific IgE to natural rubber latex (NRL) allergens and disinfectants was also found. Serum sensitisation to cat allergens and daily contact with laboratory animals (LA) increased the risk for developing isolated occupational rhinitis. Furthermore, working time of more than 10 years and daily contact with LA were also significant risk factors for the development of OAA. Measuring PEFR and BHR before and after SCT is a useful method to confirm the presence of OA. Allergy to LAA is an important health problem among veterinary medicine practitioners in Poland.

Four rice seed cDNA clones belonging to the alpha-amylase/trypsin inhibitor gene family encode potential rice allergens.

PubMed

Alvarez, A M; Fukuhara, E; Nakase, M; Adachi, T; Aoki, N; Nakamura, R; Matsuda, T

1995-07-01

Four rice seed proteins encoded by cDNAs belonging to the alpha-amylase/trypsin inhibitor gene family were overexpressed as TrpE-fusion proteins in E. coli. The expressed rice proteins were detected by SDS-PAGE as major proteins in bacterial cell lysates. Western blot analyses showed that all the recombinant proteins were immunologically reactive to rabbit polyclonal antibodies and to a mouse monoclonal antibody (25B9) specific for a previously isolated rice allergen of 16 kDa. Some truncated proteins from deletion mutants of the cDNAs retained their reactivity to the specific antibodies. These results suggest that the cDNAs encode potential rice allergens and that some epitopes of the recombinant proteins are still immunoreactive when they are expressed as their fragments.

Expression, purification and characterization of Der f 27, a new allergen from dermatophagoides farinae

PubMed Central

Lin, Jianli; Li, Meng; Liu, Yulin; Jiang, Congli; Wu, Yulan; Wang, Yuanyuan; Gao, Anjian; Liu, Zhigang; Yang, Pingchang; Liu, Xiaoyu

2015-01-01

The house dust mite (HDM), Dermatophagoidesfarinae (D. farina), is one of the most important indoor allergen sources and a major elicitor of allergic asthma; itscharacterization is important in the diagnosis and immunotherapy of mite allergen-relevant diseases. This study aims to characterize a novel allergen, the D. farinae-derived serpin (Der f 27). In this study, the total RNA of D. farinae was extracted, and the Der f 27 gene was cloned and expressed. The allergenicity of recombinant Der f 27 protein was determined by enzyme-linked immunosorbent assay, and Western-blotting with the sera of asthma patients, and skin prick test (SPT) in allergic human subjects. A r-Der f 27 allergic asthma mouse model was established. The cloned Der f 27 gene has been presented at the Gene Bank with an accession number of KM009995. The IgE levels of r-Der f 27 in the serum from r-Der f 27 SPT positive allergic patients were 3 folds more than healthy subjects. The Der f 27 SPT positive ratewas 42.1% in 19 DM-SPT positive patients. Airway hyperresponsiveness, serum specific IgE, and levels of interleukin-4 in the spleen cell culture supernatant were significantly increased in allergic asthma mice sensitized to r-Der f 27. In conclusion, Der f 27 is a new subtype of house mite allergen. PMID:26328010

DOSE-DEPENDENT ALLERGIC ASTHMA RESPONSES TO PENICILLIUM CHRYSOGENUM

EPA Science Inventory

ABSTRACT
Indoor mold has been associated with development of allergic asthma. Penicillium chrysogenum, a common indoor mold, is known to have several allergens and its viable conidia can induce allergic responses in a mouse model of allergic penicilliosis. The hypothesis o...

Reduction of the IgE-binding ability and maintenance of immunogenicity of gamma-irradiated Dermatophagoides farinae

NASA Astrophysics Data System (ADS)

Lee, Ju-Woon; Seo, Ji-Hyun; Kim, Jae-Hun; Lee, Soo-Young; Park, Joong-Won; Byun, Myung-Woo

2007-11-01

House dust mites, Dermatophagoides farinae (DF) and Dermatophagoides pteronyssinus, are major allergens in the most common indoor allergen and are important risk factor for asthma. The modified antigen has been studied to treat allergic disorder. This study was carried out to measure possibility of modified allergen using gamma irradiation to treat allergy such as asthma. DF solutions (2 mg/ml) as target allergen were irradiated with Co-60 at 50 and 100 kGy. Conformational alternation of irradiated DF was observed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Levels of anti-irradiated DF mouse IgGs (sub-isotypes) against intact DF were measured similar to that of anti-intact DF IgGs. The binding abilities of house dust mite-allergic patients' IgE were reduced depending on radiation dose, and irradiation could inhibit the binding ability of patients' IgE more than 40%. This study has shown that the binding ability of IgE was reduced by conformational alteration by irradiation and the irradiated DF had epitopes capable to induce immunogeniciy.

An odorant-binding protein as a new allergen from Siberian hamster (Phodopus sungorus).

PubMed

Torres, J A; Pastor-Vargas, C; de las Heras, M; Vivanco, F; Cuesta, Javier; Sastre, J

2012-01-01

A case of anaphylaxis following a bite from a Siberian hamster (SH; Phodopus sungorus) is described. Skin prick tests with hair, urine and salivary gland extracts from SH were positive, while the tests were negative for hair extracts from other rodents. IgE immunoblotting with the patient serum revealed 3 IgE-binding bands of about 18, 21 and 23 kDa. When the patient's serum was preincubated with rabbit, mouse and gerbil hair extracts, no inhibition of the 3 SH IgE-binding bands was demonstrated. Proteins extracted from the 3 bands were analyzed by N-terminal sequencing and matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry, and peptides were sequenced. IgE-binding bands were identified as being an odorant-binding protein belonging to the lipocalin family. Analysis of the 3 IgE-binding bands found in the hair, urine and salivary glands of SH showed a new allergenic protein lacking cross-reactivity with allergens from other rodents. The 3 bands likely correspond to isoforms of a single allergen. Copyright © 2011 S. Karger AG, Basel.

For t 2 DNA vaccine prevents Forcipomyia taiwana (biting midge) allergy in a mouse model.

PubMed

Lee, M-F; Song, P-P; Lin, T-M; Chiu, Y-T; Chen, Y-H

2016-04-01

Forcipomyia taiwana (biting midge) is the most prevalent allergenic biting insect in Taiwan, and 60% of the exposed subjects develop allergic reactions. Subjects with insect allergy frequently limit their outdoor activities to avoid the annoyingly intense itchy allergic reactions, leading to significant worsening of their quality of life. Allergen-specific immunotherapy is the only known therapy that provides long-term host immune tolerance to the allergen, but is time-consuming and cumbersome. This study tested whether the For t 2 DNA vaccine can prevent allergic symptoms in For t 2-sensitized mice. Two consecutive shots of For t 2 DNA vaccine were given to mice with a 7-day interval before sensitization with recombinant For t 2 proteins, using the two-step sensitization protocol reported previously. The For t 2 DNA vaccine at 50 μg prevented the production of For t 2-specific IgE (P < 0.05), as well as midge allergen-challenge-induced scratch bouts, midge allergen-induced IL-13 and IL-4 production from splenocytes, and inflammatory cell infiltrations in the lesions 48 h after intradermal challenge. This study is the first to demonstrate that DNA vaccine encoding midge allergen is effective in preventing allergic skin inflammation induced by biting midge. Immunotherapy using For t 2 DNA vaccine can protect mice from being sensitized by midge allergen and may be a promising treatment for biting midge allergy in the future. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

[Evaluation of the total biological activity and allergenic composition of allergenic extracts].

PubMed

Lombardero, M; González, R; Duffort, O; Juan, F; Ayuso, R; Ventas, P; Cortés, C; Carreira, J

1986-01-01

In the present study, a complete procedure is presented in order to standardize allergenic extracts, the meaning of which is the measurement of the total allergenic activity and the determination of the allergenic composition. The measurement of the biological activity comprises 2 steps: Preparation of Reference Extracts and determination of their "in vivo" activity. Evaluation of the total allergenic activity of extracts for clinical use. Reference extracts were prepared from the main allergens and their "in vivo" biological activity was determined by a quantitative skin prick test in a sample of at least 30 allergic patients. By definition, the protein concentration of Reference Extract that produces, in the allergic population, a geometric mean wheal of 75 mm.2 has an activity of 100 biological units (BUs). The determination of the biological activity of a problem extract is made by RAST inhibition. The sample is compared with the corresponding Reference Extract by this technique and, from this comparison, it is possible to quantify the activity of the problem extract in biologic units (BUs) with clinical significance. Likewise, different techniques have been used to determine the allergenic composition of extracts. These techniques comprise 2 steps: Separation of the components of the extract. Identification of the components that bind specific human IgE. The separation of the components of the extract has been carried out by isoelectric focusing (IEF) and electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE). In order to identify the allergenic components, an immunoblotting technique has been employed. The separated components in the IEF gel or SDS-PAGE gel are transferred to a nitrocellulose sheet and later on, this membrane is overlaid with a serum pool from allergic patients and a mouse monoclonal anti-human IgE, labelled with 125I. Finally, the autoradiography of the nitrocellulose membrane is obtained. In this way it is possible to compare the allergenic composition of an extract with the corresponding Reference Extract and so to employ for clinical use only those extracts with the right allergenic composition.

AN EXTRACT OF PENICILLIUM CHRYSOGENUM INDUCES DOSE-DEPENDENT ALLERGIC ASTHMA RESPONSES IN MICE

EPA Science Inventory

Rationale: Penicillium chrysogenum, a common indoor mold, is known to have several allergens and can induce allergic responses in a mouse model of allergic penicilliosis. Our hypothesis is that soluble components of P. chrysogenum (PCE) can dose-dependently induce responses typ...

DOSE-DEPENDENT ALLERGIC RESPONSES TO AN EXTRACT OF PENICILLIUM CHRYSOGENUM IN BALB/MICE

EPA Science Inventory

Indoor mold has been associated with the development of allergic asthma. Penicillium chrysogenum, a common indoor mold, is known to have several allergens and can induce allergic responses in a mouse model of allergic penicilliosis. Our hypothesis is that soluble components of ...

RELATIVE POTENCY OF ORAL ANTIGENS IN PROVOKING FOOD ALLERGY IN THE MOUS

EPA Science Inventory

Rationale: An animal model for food allergy is needed to test novel proteins produced through biotechnology for potential allergenicity. While the oral route is the most relevant method of exposure, oral tolerance is an impediment. We demonstrate that mice can distinguish...

Experience with a mouse intranasal test for the predictive identification of respiratory sensitization potential of proteins.

PubMed

Blaikie, L; Basketter, D A

1999-08-01

The predictive identification of respiratory allergenic potential is an important primary step in the safety evaluation of (novel) proteins, such as the enzymes used in a range of consumer laundry products. In the past this has been achieved by assessing the relative ability of proteins to give rise to the formation of anaphylactic antibody in the guinea pig. Recently, an alternative model has been proposed which assesses the formation of specific IgG1 antibody in a mouse intranasal test (MINT), the assumption being that specific IgG1 antibody is a surrogate for anaphylactic antibody in the mouse. This procedure has undergone successful initial intralaboratory and interlaboratory assessment. In the present work, the MINT has been evaluated in a more thorough intralaboratory study using eight enzymes plus ovalbumin. While the data generated with a reference enzyme protein, Alcalase, showed good reproducibility, results with the remaining eight proteins led to estimates of their relative antigenic or sensitization potential several of which were at variance from those derived from the guinea pig/ human experience. In consequence, it is concluded that the MINT requires substantial further investigation before it can be adopted as a model for the assessment of the relative ability of proteins to behave as respiratory allergens.

Prevention of Diabetes in NOD Mice by Repeated Exposures to a Contact Allergen Inducing a Sub-Clinical Dermatitis

PubMed Central

Engkilde, Kaare; Buschard, Karsten; Hansen, Axel Kornerup; Menné, Torkil; Johansen, Jeanne Duus

2010-01-01

Background Type 1 diabetes is an autoimmune disease, while allergic contact dermatitis although immune mediated, is considered an exposure driven disease that develops due to epicutanous contact with reactive low-molecular chemicals. The objective of the present study was to experimentally study the effect of contact allergens on the development of diabetes in NOD mice. As the link between contact allergy and diabetes is yet unexplained we also examined the effect of provocation with allergens on Natural Killer T (NKT) cells, since involvement of NKT cells could suggest an innate connection between the two diseases. Method NOD mice 4 weeks of age were exposed, on the ears, to two allergens, p-phenylenediamine and 2,4-dinitrochlorobenzene respectively, to investigate the diabetes development. The mice were followed for a maximum of 32 weeks, and they were either repeatedly exposed to the allergens or only sensitized a week after arrival. The stimulation of NKT cells by the two allergens were additionally studied in C57BL/6 mice. The mice were sensitized and two weeks later provocated with the allergens. The mice were subsequently euthanized at different time points after the provocation. Results It was found that repeated application of p-phenylenediamine reduced the incidence of diabetes compared to application with water (47% vs. 93%, P = 0.004). Moreover it was shown that in C57BL/6 mice both allergens resulted in a slight increment in the quantity of NKT cells in the liver. Application of the allergens at the same time resulted in an increased number of NKT cells in the draining auricular lymph node, and the increase appeared to be somewhat allergen specific as the accumulation was stronger for p-phenylenediamine. Conclusion The study showed that repeated topical application on the ears with a contact allergen could prevent the development of diabetes in NOD mice. The contact allergens gave a non-visible, sub-clinical dermatitis on the application site. The preventive effect on diabetes may be due to stimulation of peripheral NKT cells, as shown for provocation with p-phenylenediamine in the C57BL/6 mouse. This epicutanous procedure may lead to new strategies in prevention of type 1 diabetes in humans. PMID:20485668

Allergic Responses Induced by a Fungal Biopesticide Metarhizium anisopliae and House Dust Mite are Compared in a Mouse Model

EPA Science Inventory

Biopesticides can be effective in controlling their target pest. However, research regarding mammalian health impacts of these agents has focused on toxicity and pathogenicity, with limited research regarding allergenicity and asthma development. We compared the ability of funga...

The relative allergenicity of Stachybotrys chartarum compared to house dust mite extracts in a mouse model

EPA Science Inventory

A report by the Institute of Medicine suggested that more research is needed to better understand mold effects on allergic disease, particularly asthma development. The authors compared the ability of the fungus Stachybotrys chartarum (SCE) and house dust mite (HDM) extracts to i...

Assessing the Allergenic Potential of Molds Found in Water-Damaged Homes in a Mouse Model

EPA Science Inventory

Damp/moldy indoor environments, which have resulted from flooding events and may increase as a result of climate change, have been associated with asthma exacerbation. Certain molds found in significantly higher or lower concentrations in asthmatics’ homes compared to control ho...

DOSE-DEPENDENT ALLERGIC RESPONSES TO AN EXTRACT OF PENICILLIUM CHRYSOGENUM IN BAL/C MICE

EPA Science Inventory

Indoor mold has been associated with the development of allergic asthma. Penicillium chrysogenum, a common indoor mold, is known to have several allergens and can induce allergic responses in a mouse model of allergic penicilliosis. Our hypothesis is that soluble components of ...

Genetically modified plants and food hypersensitivity diseases: usage and implications of experimental models for risk assessment.

PubMed

Prescott, Vanessa E; Hogan, Simon P

2006-08-01

The recent advances in biotechnology in the plant industry have led to increasing crop production and yield that in turn has increased the usage of genetically modified (GM) food in the human food chain. The usage of GM foods for human consumption has raised a number of fundamental questions including the ability of GM foods to elicit potentially harmful immunological responses, including allergic hypersensitivity. To assess the safety of foods derived from GM plants including allergenic potential, the US FDA, Food and Agriculture Organization of the United Nations (FAO)/World Health Organization (WHO), and the EU have developed approaches for evaluation assessment. One assessment approach that has been a very active area of research and debate is the development and usage of animal models to assess the potential allergenicity of GM foods. A number of specific animal models employing rodents, pigs, and dogs have been developed for allergenicity assessment. However, validation of these models is needed and consideration of the criteria for an appropriate animal model for the assessment of allergenicity in GM plants is required. We have recently employed a BALB/c mouse model to assess the potential allergenicity of GM plants. We have been able to demonstrate that this model is able to detect differences in antigenicity and identify aspects of protein post-translational modifications that can alter antigenicity. Furthermore, this model has also enabled us to examine the usage of GM plants as a therapeutic approach for the treatment of allergic diseases. This review discusses the current approaches to assess the allergenic potential of GM food and particularly focusing on the usage of animal models to determine the potential allergenicity of GM foods and gives an overview of our recent findings and implications of these studies.

Cockroach allergen exposure and plasma cytokines among children in a tropical environment.

PubMed

Medsker, Brock H; Forno, Erick; Han, Yueh-Ying; Acosta-Pérez, Edna; Colón-Semidey, Angel; Alvarez, Maria; Alcorn, John F; Canino, Glorisa J; Celedón, Juan C

2017-07-01

Little is known about the effects of socioeconomic status or cockroach allergen on immune responses in school-age children, particularly in tropical environments. To examine whether cockroach allergen and/or socioeconomic status is associated with plasma cytokine levels in Puerto Rican children. This was a cross-sectional study of 532 children (6-14 years old) with (n = 272) and without (n = 260) asthma in San Juan (Puerto Rico). House dust allergens (cockroach [Bla g 2], dust mite [Der p 1], cat dander [Fel d 1], dog dander [Can f 1], and mouse urinary protein [Mus m 1]) were quantified using monoclonal antibody arrays. A panel of 14 cytokines (interleukin [IL]-1β, IL-4, IL-6, IL-10, IL-17A, IL-17F, IL-21, IL-22, IL-23, IL-25, IL-31, IL-33, interferon-γ, and tumor necrosis factor-α) was measured in plasma samples. Low household income was defined as less than $15,000 per year (below the median income for Puerto Rico in 2008-2009). Linear regression was used for the analysis of cockroach allergen and plasma cytokines. In a multivariable analysis adjusting for low income and other allergen levels, cockroach allergen was significantly associated with decreased IL-17A and with increased levels of 8 cytokines (IL-4, IL-10, IL-17F, IL-21, IL-25, IL-31, interferon-γ, and tumor necrosis factor-α). After stratifying this analysis by cockroach allergy (ie, having a cockroach positive immunoglobulin E reaction), our findings remained largely unchanged for children sensitized to cockroach but became weaker and statistically nonsignificant for non-sensitized children. Cockroach allergen has broad effects on adaptive immune responses in school-age children in a tropical environment, particularly in those sensitized to cockroach. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Peripheral erythrocytes decrease upon specific respiratory challenge with grass pollen allergen in sensitized mice and in human subjects.

PubMed

Jordakieva, Galateja; Wallmann, Julia; Schmutz, René; Lemell, Patrick; Wegmann, Michael; Nittke, Thomas; Mittlböck, Martina; Fehrenbach, Heinz; Godnic-Cvar, Jasminka; Zieglmayer, René; Jensen-Jarolim, Erika

2014-01-01

Specific hyper-responsiveness towards an allergen and non-specific airway hyperreactivity both impair quality of life in patients with respiratory allergic diseases. We aimed to investigate cellular responses following specific and non-specific airway challenges locally and systemically in i) sensitized BALB/c mice challenged with grass pollen allergen Phl p 5, and in ii) grass pollen sensitized allergic rhinitis subjects undergoing specific airway challenge in the Vienna Challenge Chamber (VCC). BALB/c mice (n = 20) were intraperitoneally immunized with grass pollen allergen Phl p 5 and afterwards aerosol challenged with either the specific allergen Phl p 5 (n = 10) or the non-specific antigen ovalbumin (OVA) (n = 10). A protocol for inducing allergic asthma as well as allergic rhinitis, according to the united airway concept, was used. Both groups of exposed mice showed significantly reduced physical activity after airway challenge. Specific airway challenge further resulted in goblet cell hyperplasia, enhanced mucous secretion, intrapulmonary leukocyte infiltration and lymphoid follicle formation, associated with significant expression of IL-4, IL-5 and IL-13 in splenocytes and also partially in lung tissue. Concerning circulating blood cell dynamics, we observed a significant drop of erythrocyte counts, hemoglobin and hematocrit levels in both mouse groups, challenged with allergen or OVA. A significant decrease in circulating erythrocytes and hematocrit levels after airway challenges with grass pollen allergen was also found in grass pollen sensitized human rhinitis subjects (n = 42) at the VCC. The effects on peripheral leukocyte counts in mice and humans however were opposed, possibly due to the different primary inflammation sites. Our data revealed that, besides significant leukocyte dynamics, particularly erythrocytes are involved in acute hypersensitivity reactions to respiratory allergens. A rapid recruitment of erythrocytes to the lungs to compensate for hypoxia is a possible explanation for these findings.

Specific B-cell Epitope of Per a 1: A Major Allergen of American Cockroach (Periplaneta americana) and Anatomical Localization.

PubMed

Sookrung, Nitat; Khetsuphan, Thanyathon; Chaisri, Urai; Indrawattana, Nitaya; Reamtong, Onrapak; Chaicumpa, Wanpen; Tungtrongchitr, Anchalee

2014-07-01

Cockroach (CR) is a common source of indoor allergens, and Per a 1 is a major American CR (Periplaneta americana) allergen; however, several attributes of this protein remain unknown. This study identifies a novel specific B cell epitope and anatomical locations of Per a 1.0105. Recombinant Per a 1.0105 (rPer a 1.0105) was used as BALB/c mouse immunogen for the production of monoclonal antibodies (MAb). The MAb specific B cell epitope was identified by determining phage mimotopic peptides and pair-wise alignment of the peptides with the rPer a 1.0105 amino acid sequence. Locations of the Per a 1.0105 in P. americana were investigated by immunohistochemical staining. The rPer a 1.0105 (~13 kDa) had 100%, 98% and ≥90% identity to Per a 1.0105, Per a 1.0101, and Cr-PII, respectively. The B-cell epitope of the Per a 1.0105 specific-MAb was located at residues(99) QDLLLQLRDKGV(110) contained in all 5 Per a 1.01 isoforms and Per a 1.02. The epitope was analogous to the Bla g 1.02 epitope; however, this B-cell epitope was not an IgE inducer. Per a 1.0105 was found in the midgut and intestinal content of American CR but not in the other organs. The amount of the Per a 1 was ~544 ℃g per gram of feces. The novel Per a 1 B-cell epitope described in this study is a useful target for allergen quantification in samples; however, the specific MAb can be used as an allergen detection reagent. The MAb based-affinity resin can be made for allergen purification, and the so-purified protein can serve as a standard and diagnostic allergen as well as a therapeutic vaccine component. The finding that the Per a 1 is contained in the midgut and feces is useful to increase yield and purity when preparing this allergen.

Ear swelling test by using laser speckle imaging with a long exposure time

NASA Astrophysics Data System (ADS)

Kalchenko, Vyacheslav; Kuznetsov, Yuri; Preise, Dina; Meglinski, Igor; Harmelin, Alon

2014-06-01

Laser speckle imaging with long exposure time has been applied noninvasively to visualize the immediate reaction of cutaneous vessels in mice in response to a known primary irritant and potential allergen-methyl salicylate. The compound has been used topically on the surface of the pinna and the reaction of the vascular network was examined. We demonstrate that irritant-induced acute vascular reaction can be effectively and accurately detected by laser speckle imaging technique. The current approach holds a great promise for application in routine screening of the cutaneous vascular response induced by contact agents, screenings of mouse ear swelling test, and testing the allergenic potential of new synthetic materials and healthcare pharmaceutical products.

Novel T-cell epitopes of ovalbumin in BALB/c mouse: Potential for peptide-immunotherapy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Marie; Mine, Yoshinori

The identification of food allergen T-cell epitopes provides a platform for the development of novel immunotherapies. Despite extensive knowledge of the physicochemical properties of hen ovalbumin (OVA), a major egg allergen, the complete T-cell epitope map of OVA has surprisingly not been defined in the commonly used BALB/c mouse model. In this study, spleen cells obtained from OVA-sensitized mice were incubated in the presence of 12-mer overlapping synthetic peptides, constructed using the SPOTS synthesis method. Proliferative activity was assessed by 72-h in vitro assays with use of the tetrazolium salt WST-1 and led to identification of four mitogenic sequences, i.e.,more » A39R50, S147R158, K263E274, and A329E340. ELISA analyses of interferon (IFN)-{gamma} and interleukin (IL)-4 productions in cell culture supernatants upon stimulation with increasing concentrations of peptides confirmed their immunogenicity. Knowledge of the complete T-cell epitope map of OVA opens the way to a number of experimental investigations, including the exploration of peptide-based immunotherapy.« less

Sensitizing and Eliciting Capacity of Egg White Proteins in BALB/c Mice As Affected by Processing.

PubMed

Pablos-Tanarro, Alba; Lozano-Ojalvo, Daniel; Martínez-Blanco, Mónica; López-Fandiño, Rosina; Molina, Elena

2017-06-07

This study assesses to what extent technological processes that lead to different degrees of denaturation of egg white proteins affect their allergenicity. We focused on heat (80 °C, 10 min) and high-pressure (400 MPa and 37 °C, 10 min) treatments and used a BALB/c mouse model of food allergy. Oral sensitization to egg white using cholera toxin as adjuvant induced the production of IgE and IgG1 isotypes and led to severe clinical signs following challenge with the allergen. Extensive protein denaturation caused by heat treatment increased its ability to induce Th1 responses and reduced both its sensitizing and eliciting capacity. Heated egg white stimulated the production of IgE over IgG1 antibodies directed, at least in part, toward new epitopes exposed as a result of heat treatment. Conversely, partial denaturation caused by high-pressure treatment increased the ability of egg white to stimulate Th2 responses and its allergenic potential.

Targeting a cross-reactive Gly m 5 soy peptide as responsible for hypersensitivity reactions in a milk allergy mouse model.

PubMed

Curciarello, Renata; Smaldini, Paola L; Candreva, Angela M; González, Virginia; Parisi, Gustavo; Cauerhff, Ana; Barrios, Ivana; Blanch, Luis Bruno; Fossati, Carlos A; Petruccelli, Silvana; Docena, Guillermo H

2014-01-01

Cross-reactivity between soybean allergens and bovine caseins has been previously reported. In this study we aimed to map epitopes of the major soybean allergen Gly m 5 that are co-recognized by casein specific antibodies, and to identify a peptide responsible for the cross-reactivity. Cow's milk protein (CMP)-specific antibodies were used in different immunoassays (immunoblotting, ELISA, ELISA inhibition test) to evaluate the in vitro recognition of soybean proteins (SP). Recombinant Gly m 5 (α), a truncated fragment containing the C-terminal domain (α-T) and peptides of α-T were obtained and epitope mapping was performed with an overlapping peptide assay. Bioinformatics tools were used for epitope prediction by sequence alignment, and for modelling the cross-recognized soy proteins and peptides. The binding of SP to a monoclonal antibody was studied by surface Plasmon resonance (SPR). Finally, the in vivo cross-recognition of SP was assessed in a mouse model of milk allergy. Both α and α-T reacted with the different CMP-specific antibodies. α-T contains IgG and IgE epitopes in several peptides, particularly in the peptide named PA. Besides, we found similar values of association and dissociation constants between the α-casein specific mAb and the different milk and soy components. The food allergy mouse model showed that SP and PA contain the cross-reactive B and T epitopes, which triggered hypersensitivity reactions and a Th2-mediated response on CMP-sensitized mice. Gly m 5 is a cross-reactive soy allergen and the α-T portion of the molecule contains IgG and IgE immunodominant epitopes, confined to PA, a region with enough conformation to be bound by antibodies. These findings contribute to explain the intolerance to SP observed in IgE-mediated CMA patients, primarily not sensitised to SP, as well as it sets the basis to propose a mucosal immunotherapy for milk allergy using this soy peptide.

Efficacy of a therapeutic treatment using gas-filled microbubble-associated phospholipase A2 in a mouse model of honeybee venom allergy.

PubMed

Corthésy, B; Lassus, A; Terrettaz, J; Tranquart, F; Bioley, G

2016-07-01

Venom immunotherapy is efficient to desensitize people suffering from insect sting allergies. However, the numerous injections required over several years and important risks of severe side reactions complicate the widespread use of immunotherapy. In the search for novel approaches to blunt the overwhelming pro-allergic Th2 response, we evaluated the therapeutic efficacy of a treatment based on a denatured form of the major allergen, phospholipase A2, associated with microbubbles (PLA2denat -MB) in a mouse model of honeybee venom allergy. Antibodies measured by ELISA, T-cell responses assessed by CFSE-based proliferation assays and ELISA, and basophil degranulation were examined after PLA2denat -MB-based therapeutic treatment of sensitized mice. Mice were challenged with a lethal dose of PLA2 to evaluate protection against anaphylaxis. Therapeutic subcutaneous administration of two different PLA2denat -MB formulations, in contrast to PLA2denat alone, reduced allergic symptoms and protected all mice from anaphylaxis-mediated death after allergen challenge. At the functional level, the use of PLA2denat decreased IgE-mediated basophil degranulation as compared to the native form of the allergen. In comparison with PLA2denat alone, both PLA2denat -MB formulations decreased allergen-specific Th2 CD4 T-cell reactivity. At the mechanistic level, PLA2denat -MB containing 20% palmitic acid and PEG induced PLA2-specific IgA and increased Foxp3(+) Treg frequencies and TGF-β production, whereas the formulation bearing 80% palmitic acid triggered the production of IFN-γ, IgG2a, and IgG3. In contrast to conventional PLA2 subcutaneous immunotherapy, the therapeutic administration of PLA2-MB treatment to mice that already had established allergy to PLA2 protects all subsequently challenged animals. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Development of β-lactoglobulin-specific chimeric human IgEκ monoclonal antibodies for in vitro safety assessment of whey hydrolysates.

PubMed

Knipping, Karen; Simons, Peter J; Buelens-Sleumer, Laura S; Cox, Linda; den Hartog, Marcel; de Jong, Niels; Teshima, Reiko; Garssen, Johan; Boon, Louis; Knippels, Léon M J

2014-01-01

Cow's milk-derived whey hydrolysates are nutritional substitutes for allergic infants. Safety or residual allergenicity assessment of these whey hydrolysates is crucial. Currently, rat basophilic leukemia RBL-2H3 cells expressing the human IgE receptor α-chain (huFcεRIα-RBL-2H3), sensitized with serum IgE from cow's milk allergic children, are being employed to assess in vitro residual allergenicity of these whey hydrolysates. However, limited availability and inter-lot variation of these allergic sera impede standardization of whey hydrolysate safety testing in degranulation assays. An oligoclonal pool of chimeric human (chu)IgE antibodies against bovine β-lactoglobulin (a major allergen in whey) was generated to increase sensitivity, specificity, and reproducibility of existing degranulation assays. Mice were immunized with bovine β-lactoglobulin, and subsequently the variable domains of dissimilar anti-β-lactoglobulin mouse IgG antibodies were cloned and sequenced. Six chimeric antibodies were generated comprising mouse variable domains and human constant IgE/κ domains. After sensitization with this pool of anti-β-lactoglobulin chuIgEs, huFcεRIα-expressing RBL-2H3 cells demonstrated degranulation upon cross-linking with whey, native 18 kDa β-lactoglobulin, and 5-10 kDa whey hydrolysates, whereas a 3 kDa whey hydrolysate and cow's milk powder (mainly casein) showed no degranulation. In parallel, allergic serum IgEs were less sensitive. In addition, our pool anti-β-lactoglobulin chuIgEs recognized multiple allergenic immunodominant regions on β-lactoglobulin, which were also recognized by serum IgEs from cow's milk allergic children. Usage of our 'unlimited' source and well-defined pool of β-lactoglobulin-specific recombinant chuIgEs to sensitize huFcεRIα on RBL-2H3 cells showed to be a relevant and sensitive alternative for serum IgEs from cow's milk allergic patients to assess safety of whey-based non-allergic hydrolyzed formula.

Sensitization prevalence, antibody cross-reactivity and immunogenic peptide profile of Api g 2, the non-specific lipid transfer protein 1 of celery.

PubMed

Gadermaier, Gabriele; Hauser, Michael; Egger, Matthias; Ferrara, Rosetta; Briza, Peter; Santos, Keity Souza; Zennaro, Danila; Girbl, Tamara; Zuidmeer-Jongejan, Laurian; Mari, Adriano; Ferreira, Fatima

2011-01-01

Celery (Apium graveolens) represents a relevant allergen source that can elicit severe reactions in the adult population. To investigate the sensitization prevalence and cross-reactivity of Api g 2 from celery stalks in a Mediterranean population and in a mouse model. 786 non-randomized subjects from Italy were screened for IgE reactivity to rApi g 2, rArt v 3 (mugwort pollen LTP) and nPru p 3 (peach LTP) using an allergen microarray. Clinical data of 32 selected patients with reactivity to LTP under investigation were evaluated. Specific IgE titers and cross-inhibitions were performed in ELISA and allergen microarray. Balb/c mice were immunized with purified LTPs; IgG titers were determined in ELISA and mediator release was examined using RBL-2H3 cells. Simulated endolysosomal digestion was performed using microsomes obtained from human DCs. IgE testing showed a sensitization prevalence of 25.6% to Api g 2, 18.6% to Art v 3, and 28.6% to Pru p 3 and frequent co-sensitization and correlating IgE-reactivity was observed. 10/32 patients suffering from LTP-related allergy reported symptoms upon consumption of celery stalks which mainly presented as OAS. Considerable IgE cross-reactivity was observed between Api g 2, Art v 3, and Pru p 3 with varying inhibition degrees of individual patients' sera. Simulating LTP mono-sensitization in a mouse model showed development of more congruent antibody specificities between Api g 2 and Art v 3. Notably, biologically relevant murine IgE cross-reactivity was restricted to the latter and diverse from Pru p 3 epitopes. Endolysosomal processing of LTP showed generation of similar clusters, which presumably represent T-cell peptides. Api g 2 represents a relevant celery stalk allergen in the LTP-sensitized population. The molecule displays common B cell epitopes and endolysosomal peptides that encompass T cell epitopes with pollen and plant-food derived LTP.

The high molecular weight dipeptidyl peptidase IV Pol d 3 is a major allergen of Polistes dominula venom.

PubMed

Schiener, Maximilian; Hilger, Christiane; Eberlein, Bernadette; Pascal, Mariona; Kuehn, Annette; Revets, Dominique; Planchon, Sébastien; Pietsch, Gunilla; Serrano, Pilar; Moreno-Aguilar, Carmen; de la Roca, Federico; Biedermann, Tilo; Darsow, Ulf; Schmidt-Weber, Carsten B; Ollert, Markus; Blank, Simon

2018-01-22

Hymenoptera venom allergy can cause severe anaphylaxis in untreated patients. Polistes dominula is an important elicitor of venom allergy in Southern Europe as well as in the United States. Due to its increased spreading to more moderate climate zones, Polistes venom allergy is likely to gain importance also in these areas. So far, only few allergens of Polistes dominula venom were identified as basis for component-resolved diagnostics. Therefore, this study aimed to broaden the available panel of important Polistes venom allergens. The 100 kDa allergen Pol d 3 was identified by mass spectrometry and found to be a dipeptidyl peptidase IV. Recombinantly produced Pol d 3 exhibited sIgE-reactivity with approximately 66% of Polistes venom-sensitized patients. Moreover, its clinical relevance was supported by the potent activation of basophils from allergic patients. Cross-reactivity with the dipeptidyl peptidases IV from honeybee and yellow jacket venom suggests the presence of exclusive as well as conserved IgE epitopes. The obtained data suggest a pivotal role of Pol d 3 as sensitizing component of Polistes venom, thus supporting its status as a major allergen of clinical relevance. Therefore, Pol d 3 might become a key element for proper diagnosis of Polistes venom allergy.

ASSESSMENT OF ALLERGIC RESPONSES TO FOOD PROTEINS USING A NOVEL AND SENSITIVE ADJUVANT-FREE INGESTION-BASED MOUSE MODEL

EPA Science Inventory

The Unique Molecular Signatures of Contact Dermatitis and Implications for Treatment.

PubMed

Leonard, Alexandra; Guttman-Yassky, Emma

2018-05-12

Irritant contact dermatitis (ICD) and allergic contact dermatitis (ACD) are common skin disorders that are characterized by inflammation, oozing, crusting, and pruritus. Atopic dermatitis (AD) is an inflammatory skin disease characterized by immune and barrier abnormalities and is additionally a risk factor for acquiring ICD and ACD. New work on allergic sensitization to common allergens (e.g., nickel and fragrance) in human skin has shown that different allergens have distinct molecular fingerprinting. For example, nickel promotes strong Th1/Th17 polarization, whereas fragrance allergy causes Th2/Th22 skewing, which is similar to the phenotype of AD. While ACD has previously been considered to be constant across all allergens, largely based on mouse models involving strong sensitizers, these new data suggest that ACD differs mechanistically according to allergen. Further, ACD in the setting of concurrent AD shows a different and attenuated phenotype as compared to healthy individuals with ACD, which influences the way AD patients respond to vaccination and other treatment modalities. As in contact sensitization, skin challenged by food patch testing shows that common food allergens (e.g., peanut and barley) also cause distinct immune polarizations in the skin. Additionally, house dust mite reactions in human skin have been profiled to show unique Th2, Th9, and Th17/22 activation as compared to controls, which are similar to the phenotype of psoriasis and contact responses to nickel. Given this information, ACD patients should be treated based on their unique allergen polarity. Refined understanding of the molecular behavior of contact dermatitis and related diseases translates to improved methods of inducing tolerance in sensitized allergic patients, such as with targeted drug therapy and epicutaneous immunotherapy.

Mapping of IgE-binding regions on recombinant Cyn d 1, a major allergen from Bermuda Grass Pollen (BGP).

PubMed

Tiwari, Ruby; Bhalla, Prem L; Singh, Mohan B

2009-02-02

Bermuda grass (Cynodon dactylon; subfamily Chloridoideae) is an important source of seasonal aeroallergens in warm tropical and sub-tropical areas worldwide. Improved approaches to diagnosis and therapy of allergic diseases require a thorough understanding of the structure and epitopes on the allergen molecule that are crucial for the antigen-antibody interaction. This study describes the localization of the human IgE-binding regions of the major group 1 pollen allergen Cyn d 1 from Bermuda grass. A cDNA library was constructed from Bermuda grass pollen (BGP) using a Lambda gt11 expression vector. The gene encoding the Cyn d 1 allergen was isolated by screening the library with a mouse monoclonal antibody raised against grass group 1 allergen. In order to characterize the IgE epitopes on Cyn d 1, seven overlapping fragments and three deletion mutants were cloned and over-expressed in E. coli. The recombinant fragments and deletion mutants were evaluated for their comparative IgE reactivity with sera of non atopic individuals and grass pollen allergic patients by ELISA and a dot-blot assay. Analysis of IgE binding regions by overlapping fragments and deletion mutants identified two major allergenic regions corresponding to amino acids 120-170 and 224-244. Deletion of either or both regions led to a significant reduction in IgE binding, emphasizing the importance of the C-terminal region on Cyn d 1 in epitope-IgE interaction. Anti-Cyn d 1 IgE antibodies from allergic human sera recognize two epitopes located at the C-terminal end of the molecule. These data will enable the design of improved diagnostic and therapeutic approaches for BGP hypersensitivity.

Future Therapies for Food Allergies

PubMed Central

Nowak-Węgrzyn, Anna; Sampson, Hugh A.

2011-01-01

Food allergy is an increasingly prevalent problem in westernized countries and there is an unmet medical need for an effective form of therapy . A number of therapeutic strategies are under investigation targeting foods that most frequently provoke severe IgE-mediated anaphylactic reactions (peanut, tree nuts, shellfish) or are most common in children, such as cow’s milk and hen’s egg. Approaches being pursued are both food allergen-specific and non-specific. Allergen-specific approaches include oral, sublingual and epicutaneous immunotherapy (desensitization) with native food allergens, and mutated recombinant proteins, which have decreased IgE-binding activity, co-administered within heat-killed E.coli to generate maximum immune response. Diets containing extensively heated (baked) milk and egg represent an alternative approach to food oral immunotherapy and are already changing the paradigm of strict dietary avoidance for food-allergic patients. Non-specific approaches include monoclonal anti-IgE antibodies, which may increase the threshold dose for food allergen in food-allergic patients, and a Chinese herbal formulation, which prevented peanut-induced anaphylaxis in a mouse model, and is currently being investigated in clinical trials. The variety of strategies for treating food allergy increases the likelihood of success and gives hope that accomplishing an effective therapy for food allergy is within reach. PMID:21277625

Enhanced Expression of IL-18 and IL-18BP in Plasma of Patients with Eczema: Altered Expression of IL-18BP and IL-18 Receptor on Mast Cells.

PubMed

Hu, Yalin; Wang, Junling; Zhang, Huiyun; Xie, Hua; Song, Weiwei; Jiang, Qijun; Zhao, Nan; He, Shaoheng

2017-01-01

IL-18 has been found to be associated with eczema. However, little is known of the role of IL-18 binding protein (BP) and IL-18 receptor (R) in eczema. We therefore investigated the expression of IL-18, IL-18BP, and IL-18R on mast cells by using flow cytometry analysis and mouse eczema model. The results showed that plasma free IL-18 and free IL-18BP levels in eczema patients were higher than those in healthy controls. IL-18 provoked up to 3.1-fold increase in skin mast cells. IL-18 induced also an increase in IL-18BP+ mast cells, but a reduction of IL-18R+ mast cells in mouse eczema skin. It was found that house dust mite allergen Der p1 and egg allergen OVA induced upregulation of the expression of IL-18, IL-18BP, and IL-18R mRNAs in HMC-1 cells following 2 and 16 h incubation. In conclusion, correlation of IL-18 and IL-18BP in eczema plasma suggests an important balance between IL-18 and IL-18BP in eczema. The decrease in molar concentration ratio of plasma IL-18BP/IL-18 and allergen-induced upregulated expression of IL-18 and IL-18R in skin mast cells of the patients with eczema suggests that anti-IL-18 including IL-18BP therapy may be useful for the treatment of eczema.

Enhanced Expression of IL-18 and IL-18BP in Plasma of Patients with Eczema: Altered Expression of IL-18BP and IL-18 Receptor on Mast Cells

PubMed Central

2017-01-01

IL-18 has been found to be associated with eczema. However, little is known of the role of IL-18 binding protein (BP) and IL-18 receptor (R) in eczema. We therefore investigated the expression of IL-18, IL-18BP, and IL-18R on mast cells by using flow cytometry analysis and mouse eczema model. The results showed that plasma free IL-18 and free IL-18BP levels in eczema patients were higher than those in healthy controls. IL-18 provoked up to 3.1-fold increase in skin mast cells. IL-18 induced also an increase in IL-18BP+ mast cells, but a reduction of IL-18R+ mast cells in mouse eczema skin. It was found that house dust mite allergen Der p1 and egg allergen OVA induced upregulation of the expression of IL-18, IL-18BP, and IL-18R mRNAs in HMC-1 cells following 2 and 16 h incubation. In conclusion, correlation of IL-18 and IL-18BP in eczema plasma suggests an important balance between IL-18 and IL-18BP in eczema. The decrease in molar concentration ratio of plasma IL-18BP/IL-18 and allergen-induced upregulated expression of IL-18 and IL-18R in skin mast cells of the patients with eczema suggests that anti-IL-18 including IL-18BP therapy may be useful for the treatment of eczema. PMID:28839348

Acaroid mite allergens from the filters of air-conditioning system in China.

PubMed

Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

2014-01-01

Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of allergic disorders in this area.

Acaroid mite allergens from the filters of air-conditioning system in China

PubMed Central

Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

2014-01-01

Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of allergic disorders in this area. PMID:25035772

Specific B-cell Epitope of Per a 1: A Major Allergen of American Cockroach (Periplaneta americana) and Anatomical Localization

PubMed Central

Sookrung, Nitat; Khetsuphan, Thanyathon; Chaisri, Urai; Indrawattana, Nitaya; Reamtong, Onrapak; Chaicumpa, Wanpen

2014-01-01

Purpose Cockroach (CR) is a common source of indoor allergens, and Per a 1 is a major American CR (Periplaneta americana) allergen; however, several attributes of this protein remain unknown. This study identifies a novel specific B cell epitope and anatomical locations of Per a 1.0105. Methods Recombinant Per a 1.0105 (rPer a 1.0105) was used as BALB/c mouse immunogen for the production of monoclonal antibodies (MAb). The MAb specific B cell epitope was identified by determining phage mimotopic peptides and pair-wise alignment of the peptides with the rPer a 1.0105 amino acid sequence. Locations of the Per a 1.0105 in P. americana were investigated by immunohistochemical staining. Results The rPer a 1.0105 (~13 kDa) had 100%, 98% and ≥90% identity to Per a 1.0105, Per a 1.0101, and Cr-PII, respectively. The B-cell epitope of the Per a 1.0105 specific-MAb was located at residues99 QDLLLQLRDKGV110 contained in all 5 Per a 1.01 isoforms and Per a 1.02. The epitope was analogous to the Bla g 1.02 epitope; however, this B-cell epitope was not an IgE inducer. Per a 1.0105 was found in the midgut and intestinal content of American CR but not in the other organs. The amount of the Per a 1 was ~544 ℃g per gram of feces. Conclusions The novel Per a 1 B-cell epitope described in this study is a useful target for allergen quantification in samples; however, the specific MAb can be used as an allergen detection reagent. The MAb based-affinity resin can be made for allergen purification, and the so-purified protein can serve as a standard and diagnostic allergen as well as a therapeutic vaccine component. The finding that the Per a 1 is contained in the midgut and feces is useful to increase yield and purity when preparing this allergen. PMID:24991456

Molecular and immunological approaches in quantifying the air-borne food allergen tropomyosin in crab processing facilities.

PubMed

Kamath, Sandip D; Thomassen, Marte R; Saptarshi, Shruti R; Nguyen, Hong M X; Aasmoe, Lisbeth; Bang, Berit E; Lopata, Andreas L

2014-09-01

Tropomyosin is a cross-reactive allergenic protein present in ingested shellfish species. Exposure and sensitization to this protein via inhalation is particularly important in the crustacean processing industry where workers are continuously exposed to the aerosolized form of this allergen. The aim of this study was to develop an antibody-based immunoassay to enable the specific and sensitive quantification of aerosolized tropomyosin present in the environment of two crab processing facilities. Anti-tropomyosin antibody was generated in rabbits against tropomyosins from four different crustacean species. These antibodies were purified using recombinant tropomyosin using an immuno-affinity column. The recombinant tropomyosin was also used as an allergen standard for the sandwich ELISA. In order to quantify aerosolized tropomyosin, air collection was performed in the personal breathing zone of 80 workers during two crab processing activities, edible crab (Cancer pagurus) and king crab (Paralithodes camtschaticus) using polytetrafluoroethylene filters. The purified antibody was able to detect tropomyosin selectively from different crustaceans but not from vertebrate sources. The limit of detection (LOD) for the developed sandwich ELISA was 60 picogram/m(3) and limit of quantitation (LOQ) 100 picogram/m(3). Immunoassay validation was based on linearity (R(2) 0.999), matrix interference test (78.8±6.5%), intra-assay CV (9.8%) and inter-assay CV (11%). The novel immunoassay was able to successfully identify working activities, which generated low, medium or high concentrations of the aerosolized food allergen. We describe an IgG antibody-based immunoassay for quantification of the major food allergen tropomyosin, with high sensitivity and specificity. This modified immunological approach can be adapted for the detection of other aerosolized food allergens, assisting in the identification of high-risk allergen exposure areas in the food industry. Copyright © 2014 Elsevier GmbH. All rights reserved.

Skin sensitization potency of methyl methacrylate in the local lymph node assay: comparisons with guinea-pig data and human experience.

PubMed

Betts, Catherine J; Dearman, Rebecca J; Heylings, Jon R; Kimber, Ian; Basketter, David A

2006-09-01

There is compelling evidence that contact allergens differ substantially (by 4 or 5 orders of magnitude) with respect to their inherent skin-sensitizing potency. Relative potency can now be measured effectively using the mouse local lymph node assay (LLNA) and such data form the basis of risk assessment and risk management strategies. Such determinations also facilitate distinctions being drawn between the prevalence of skin sensitization to a particular contact allergen and inherent potency. The distinction is important because chemicals that are implicated as common causes of contact allergy are not necessarily potent sensitizers. One example is provided by nickel that is undoubtedly a common cause of allergic contact dermatitis, but is a comparatively weak sensitizer in predictive tests. In an attempt to explore other examples of contact allergens where there may exist a discrepancy between prevalence and potency, we describe here analyses conducted with methyl methacrylate (MMA). Results of LLNA studies have been interpreted in the context of historical clinical data on occupational allergic contact dermatitis associated with exposure to MMA.

MyD88-dependent dendritic and epithelial cell crosstalk orchestrates immune responses to allergens.

PubMed

Thomas, S Y; Whitehead, G S; Takaku, M; Ward, J M; Xu, X; Nakano, K; Lyons-Cohen, M R; Nakano, H; Gowdy, K M; Wade, P A; Cook, D N

2018-05-01

Sensitization to inhaled allergens is dependent on activation of conventional dendritic cells (cDCs) and on the adaptor molecule, MyD88. However, many cell types in the lung express Myd88, and it is unclear how signaling in these different cell types reprograms cDCs and leads to allergic inflammation of the airway. By combining ATAC-seq with RNA profiling, we found that MyD88 signaling in cDCs maintained open chromatin at select loci even at steady state, allowing genes to be rapidly induced during allergic sensitization. A distinct set of genes related to metabolism was indirectly controlled in cDCs through MyD88 signaling in airway epithelial cells (ECs). In mouse models of asthma, Myd88 expression in ECs was critical for eosinophilic inflammation, whereas Myd88 expression in cDCs was required for Th17 cell differentiation and consequent airway neutrophilia. Thus, both cell-intrinsic and cell-extrinsic MyD88 signaling controls gene expression in cDCs and orchestrates immune responses to inhaled allergens.

Intake of Diet Including 1% Ovomucoid for 4 Weeks Induces Oral Desensitization in Ovomucoid-Specific Allergic Mouse Model.

PubMed

Maeta, Akihiro; Sakamoto, Yoko; Yuki, Sayo; Takahashi, Kyoko

2017-01-01

We propose a new oral immunotherapy (OIT) method that includes a small amount of a food allergen in the diet. However, it is not clear whether this method will induce oral desensitization and immune tolerance. Therefore, we investigated the therapeutic effectiveness using a 1% food allergen diet in an allergic mouse model. C3H/HeJ mice were sensitized to ovomucoid (OM) in alum four times at 12-d intervals. Sensitized mice were divided into two groups: the OIT group (19% casein diet with 1% OM) and the non-treated group (20% casein diet without OM). The non-sensitized mice served as the non-allergy group. The OIT treatment was performed for 4 wk. To assess desensitization and immune tolerance, we performed oral and intraperitoneal OM challenges, assessed vascular permeability of the dorsal skin, and measured allergic biomarkers. The OIT group exhibited significantly lower oral symptom scores and vascular permeability than the non-treated group, but the two groups did not differ in intraperitoneal allergy symptom scores. Furthermore, the OIT group had significantly higher OM-specific IgA levels in their plasma than the non-treated group. However, the plasma levels of OM-specific IgE, IgG1, and IgG2a were not significantly different between the OIT and the non-treated groups. These results suggest that the proposed OIT using an OM-supplemented diet may induce desensitization, but not immune tolerance, in an OM allergic mouse model.

Prevention of oral food allergy sensitization via skin application of food allergen in a mouse model.

PubMed

Li, W; Zhang, Z; Saxon, A; Zhang, K

2012-05-01

Treatment options for food allergy remain limited. Development of novel approaches for the prevention and/or treatment of severe peanut allergy and other food allergies is urgently needed. The objective of this study was to test whether skin application of food allergen can be used as a prophylactic and/or therapeutic intervention for food allergy. Balb/C mice were given 5 weekly cutaneous application of complete peanut extract (CPE) or ovalbumin (OVA) ranging from 10 to 1000 μg on the shaved back skin, followed by 5 weekly treatments with oral CPE or OVA plus cholera toxin to induce allergic reactivity to the food. At various time points, the immunologic responses and allergic clinical manifestations to allergens were examined. Skin application of a 10-1000 μg dose of CPE or OVA to structurally intact skin did not lead to allergic sensitization to peanut or OVA. Rather, cutaneous allergen application blocked, in a dose-dependent fashion, the subsequent induction of the oral sensitization including inhibiting oral sensitization-induced CPE-specific IgE, IgG1, and IgG2a production, suppressing the peanut anaphylaxis, and modulating the oral sensitization-promoted cytokine production. The cutaneous OVA application also resulted in similar results as seen with CPE application. Cutaneous application of intact skin with peanut or OVA can block the development of orally induced corresponding food allergies, suggesting that allergic tolerance to peanuts and OVA might be achieved via allergen cutaneous application. © 2012 John Wiley & Sons A/S.

Characterization of a monoclonal antibody (P40) against the 68 kD major allergen of Penicillium notatum.

PubMed

Shen, H D; Choo, K B; Chen, J H; Lin, W L; Chang, Z N; Han, S H

1992-04-01

A monoclonal antibody (MoAb P40) against the 68 kD major allergen of Penicillium notatum (P. notatum) was obtained by immunizing the mouse with a crude extract of P. notatum. Analysed by two-dimensional gel electrophoresis and immunoblotting, P40 reacted with two different isoforms of the 68 kD component of P. notatum with pIs of 5.4 and 5.5. In addition to P. notatum, P40 showed positive ELISA activity to Aspergillus fumigatus (A. fumigatus) but not to components of six other fungi including Alternaria porri, Cladosporium cladosporoides, Aureobasidium pullulans, Fusarium solani, Rhizopus arrhizus and Candida albicans. Analysed by ELISA, MoAb P40 also showed positive activity to two (P. frequentans and P. roseopurpureum) of the 10 other Penicillium species and two (A. terreus and A. flavus) of the four other Aspergillus species tested. SDS-PAGE and immunoblotting studies demonstrated P40 positive reactivity to components with MW of about 67 kD in all these Penicillium and Aspergillus species with positive ELISA activity to P40. Furthermore, immunoblotting activity of MoAb P40 to the 67 kD component of A. niger was also observed. The epitope of the 68 kD allergen of P. notatum recognized by MoAb P40 was resistant to treatment of periodate oxidation with concentration of NaIO4 up to 20 mM. This MoAb may thus be useful in the characterization and purification of the 68 kD allergen from crude extracts, and in the molecular cloning of allergen genes.

Animal danders.

PubMed

Erwin, Elizabeth A; Woodfolk, Judith A; Custis, Natalie; Platts-Mills, Thomas A E

2003-08-01

Animals release proteins into their surroundings through secretions, as excretions, or as dander. The quantity of dander that is dispersed by cats, dogs, or humans is sufficient to supply food for dust mites and to supply easily measurable quantities of proteins in dust. Fel d 1, Can f 1, and human IgA or IgG can be found in microgram quantities in dust samples. Allergens also can accumulate from the urine of wild or pet rodents. For cats and dogs, the accumulation of dander particles is not related to the cleanliness of the animals. All animals, including humans, provide a fully adequate supply of organic material for bacterial growth in a carpet, provided conditions are sufficiently humid. The authors' preliminary results in Virginia do not find a significant difference in endotoxin between homes with or without animals. The likely explanation for the nonallergic IgG and IgG4 response to cat, dog, or rat allergens is high exposure to proteins from these animals. If the highest levels of cat allergen in a home can result in immunologic tolerance, it is unlikely that primary avoidance would be successful at reducing exposure. The data showing that 80% of Swedish children with cat allergies never had lived with a cat imply that the concentrations of cat allergen in schools or in houses without a cat are sufficient to cause sensitization. Primary prevention would be possible only on a community basis, which is unlikely to occur. Sensitization to cat, rat, dog, or mouse allergens consistently is associated with asthma. In symptomatic children with positive skin test results, there is a strong case for allergen avoidance and a clear need for controlled trials. Controlled trials of avoidance should include houses without cats and schools. Controlling exposure to cat allergens with the cat in situ requires aggressive measures, such as removing reservoirs, washing the cat, and air cleaning. Many allergic or symptomatic children who live with a cat do not have positive skin test results or positive IgE antibodies to cats. Avoidance measures related to animals should be recommended only for individuals with positive skin test results. Increasing evidence shows that exposure to cats, dogs, rats, and other animals can induce a form of immunologic tolerance without causing allergic disease, and it is important to understand why this change occurs with dander allergens rather than with all allergens. The most probable explanations are related to the form and quantity of airborne allergens.

Heat processing of peanut seed enhances the sensitization potential of the major peanut allergen Ara h 6.

PubMed

Guillon, Blanche; Bernard, Hervé; Drumare, Marie-Françoise; Hazebrouck, Stéphane; Adel-Patient, Karine

2016-12-01

Processing of food has been shown to impact IgE binding and functionality of food allergens. In the present study, we investigated the impact of heat processing on the sensitization capacity of Ara h 6, a major peanut allergen and one of the most potent elicitors of the allergic reaction. Peanut extracts obtained from raw or heat-processed peanut and some fractions thereof were biochemically and immunochemically characterized. These extracts/fractions, purified Ara h 6, or recombinant Ara h 6 including Ara h 6 mutants lacking disulfide bridges were used in in vitro digestion tests and mouse models of experimental sensitization. Peanut roasting led to the formation of complexes of high molecular weight, notably between Ara h 6 and Ara h 1, which supported the induction of IgE specific to native Ara h 6. On the contrary, a fraction containing free monomeric 2S albumins or purified native Ara h 6 displayed no intrinsic allergenicity. In addition to complex formation, heat denaturation and/or partial destabilization enhanced Ara h 6 immunogenicity and increased its sensitivity to digestion. These results suggest that sensitization potency and IgE binding capacity can be supported by different structures, modified and/or produced during food processing in interaction with other food constituents. © 2016 The Authors. Molecular Nutrition & Food Research published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Macrophages induce an allergen-specific and long-term suppression in a mouse asthma model.

PubMed

Vissers, J L M; van Esch, B C A M; Hofman, G A; van Oosterhout, A J M

2005-12-01

Increasing evidence suggests that macrophages (Mphi) play a crucial downregulatory role in the initiation and progression of allergic asthma. Recently, the current authors demonstrated that ovalbumin (OVA)-loaded Mphi (OVA-Mphi) suppress subsequent OVA-induced airway manifestations of asthma and that this effect could be potentiated upon selective activation. In the present study, the authors further delineated the underlying pathway by which Mphi exert this immunosuppressive effect. To examine the migration of OVA-Mphi, cells were labelled with 5'chloromethylfluorescein diacetate (CMFDA) and were administered (i.v.) into OVA-sensitised BALB/c mice. After 20 h, the relevant organs were dissected and analysed using fluorescent microscopy. Allergen-specificity was investigated by treating OVA-sensitised mice with keyhole limpet haemocyanin (KLH)-Mphi activated with immunostimulatory sequence oligodeoxynucleotide (ISS-ODN). By lengthening the period between treatment and challenge to 4 weeks it was examined whether OVA-Mphi exerted an immunosuppressive memory response. Strikingly, CMFDA-labelled Mphi were not trapped in the lungs, but migrated to the spleen. ISS-ODN-stimulated KLH-Mphi failed to suppress OVA-induced airway manifestations of asthma. Moreover, treatment with ISS-ODN-stimulated OVA-Mphi was still effective after lengthening the period between treatment and challenge. These data demonstrate that allergen-loaded macrophages can induce an indirect immunosuppressive response that is allergen-specific and long lasting, which are both hallmarks of a memory lymphocyte response.

Targeting a Cross-Reactive Gly m 5 Soy Peptide as Responsible for Hypersensitivity Reactions in a Milk Allergy Mouse Model

PubMed Central

Curciarello, Renata; Smaldini, Paola L.; Candreva, Angela M.; González, Virginia; Parisi, Gustavo; Cauerhff, Ana; Barrios, Ivana; Blanch, Luis Bruno; Fossati, Carlos A.

2014-01-01

Background Cross-reactivity between soybean allergens and bovine caseins has been previously reported. In this study we aimed to map epitopes of the major soybean allergen Gly m 5 that are co-recognized by casein specific antibodies, and to identify a peptide responsible for the cross-reactivity. Methods Cow's milk protein (CMP)-specific antibodies were used in different immunoassays (immunoblotting, ELISA, ELISA inhibition test) to evaluate the in vitro recognition of soybean proteins (SP). Recombinant Gly m 5 (α), a truncated fragment containing the C-terminal domain (α-T) and peptides of α-T were obtained and epitope mapping was performed with an overlapping peptide assay. Bioinformatics tools were used for epitope prediction by sequence alignment, and for modelling the cross-recognized soy proteins and peptides. The binding of SP to a monoclonal antibody was studied by surface Plasmon resonance (SPR). Finally, the in vivo cross-recognition of SP was assessed in a mouse model of milk allergy. Results Both α and α-T reacted with the different CMP-specific antibodies. α-T contains IgG and IgE epitopes in several peptides, particularly in the peptide named PA. Besides, we found similar values of association and dissociation constants between the α-casein specific mAb and the different milk and soy components. The food allergy mouse model showed that SP and PA contain the cross-reactive B and T epitopes, which triggered hypersensitivity reactions and a Th2-mediated response on CMP-sensitized mice. Conclusions Gly m 5 is a cross-reactive soy allergen and the α-T portion of the molecule contains IgG and IgE immunodominant epitopes, confined to PA, a region with enough conformation to be bound by antibodies. These findings contribute to explain the intolerance to SP observed in IgE-mediated CMA patients, primarily not sensitised to SP, as well as it sets the basis to propose a mucosal immunotherapy for milk allergy using this soy peptide. PMID:24416141

Development of β-Lactoglobulin-Specific Chimeric Human IgEκ Monoclonal Antibodies for In Vitro Safety Assessment of Whey Hydrolysates

PubMed Central

Buelens-Sleumer, Laura S.; Cox, Linda; den Hartog, Marcel; de Jong, Niels; Teshima, Reiko; Garssen, Johan; Boon, Louis; Knippels, Léon M. J.

2014-01-01

Background Cow’s milk-derived whey hydrolysates are nutritional substitutes for allergic infants. Safety or residual allergenicity assessment of these whey hydrolysates is crucial. Currently, rat basophilic leukemia RBL-2H3 cells expressing the human IgE receptor α-chain (huFcεRIα-RBL-2H3), sensitized with serum IgE from cow’s milk allergic children, are being employed to assess in vitro residual allergenicity of these whey hydrolysates. However, limited availability and inter-lot variation of these allergic sera impede standardization of whey hydrolysate safety testing in degranulation assays. Objective An oligoclonal pool of chimeric human (chu)IgE antibodies against bovine β-lactoglobulin (a major allergen in whey) was generated to increase sensitivity, specificity, and reproducibility of existing degranulation assays. Methods Mice were immunized with bovine β-lactoglobulin, and subsequently the variable domains of dissimilar anti-β-lactoglobulin mouse IgG antibodies were cloned and sequenced. Six chimeric antibodies were generated comprising mouse variable domains and human constant IgE/κ domains. Results After sensitization with this pool of anti-β-lactoglobulin chuIgEs, huFcεRIα-expressing RBL-2H3 cells demonstrated degranulation upon cross-linking with whey, native 18 kDa β-lactoglobulin, and 5–10 kDa whey hydrolysates, whereas a 3 kDa whey hydrolysate and cow’s milk powder (mainly casein) showed no degranulation. In parallel, allergic serum IgEs were less sensitive. In addition, our pool anti-β-lactoglobulin chuIgEs recognized multiple allergenic immunodominant regions on β-lactoglobulin, which were also recognized by serum IgEs from cow’s milk allergic children. Conclusion Usage of our ‘unlimited’ source and well-defined pool of β-lactoglobulin-specific recombinant chuIgEs to sensitize huFcεRIα on RBL-2H3 cells showed to be a relevant and sensitive alternative for serum IgEs from cow’s milk allergic patients to assess safety of whey-based non-allergic hydrolyzed formula. PMID:25153680

Sensitization Prevalence, Antibody Cross-Reactivity and Immunogenic Peptide Profile of Api g 2, the Non-Specific Lipid Transfer Protein 1 of Celery

PubMed Central

Gadermaier, Gabriele; Hauser, Michael; Egger, Matthias; Ferrara, Rosetta; Briza, Peter; Souza Santos, Keity; Zennaro, Danila; Girbl, Tamara; Zuidmeer-Jongejan, Laurian; Mari, Adriano; Ferreira, Fatima

2011-01-01

Background Celery (Apium graveolens) represents a relevant allergen source that can elicit severe reactions in the adult population. To investigate the sensitization prevalence and cross-reactivity of Api g 2 from celery stalks in a Mediterranean population and in a mouse model. Methodology 786 non-randomized subjects from Italy were screened for IgE reactivity to rApi g 2, rArt v 3 (mugwort pollen LTP) and nPru p 3 (peach LTP) using an allergen microarray. Clinical data of 32 selected patients with reactivity to LTP under investigation were evaluated. Specific IgE titers and cross-inhibitions were performed in ELISA and allergen microarray. Balb/c mice were immunized with purified LTPs; IgG titers were determined in ELISA and mediator release was examined using RBL-2H3 cells. Simulated endolysosomal digestion was performed using microsomes obtained from human DCs. Results IgE testing showed a sensitization prevalence of 25.6% to Api g 2, 18.6% to Art v 3, and 28.6% to Pru p 3 and frequent co-sensitization and correlating IgE-reactivity was observed. 10/32 patients suffering from LTP-related allergy reported symptoms upon consumption of celery stalks which mainly presented as OAS. Considerable IgE cross-reactivity was observed between Api g 2, Art v 3, and Pru p 3 with varying inhibition degrees of individual patients' sera. Simulating LTP mono-sensitization in a mouse model showed development of more congruent antibody specificities between Api g 2 and Art v 3. Notably, biologically relevant murine IgE cross-reactivity was restricted to the latter and diverse from Pru p 3 epitopes. Endolysosomal processing of LTP showed generation of similar clusters, which presumably represent T-cell peptides. Conclusions Api g 2 represents a relevant celery stalk allergen in the LTP-sensitized population. The molecule displays common B cell epitopes and endolysosomal peptides that encompass T cell epitopes with pollen and plant-food derived LTP. PMID:21897872

Monoclonal antibody-based ELISA to quantify the major allergen of Cynodon dactylon (Bermuda grass) pollen, Cyn d 1.

PubMed

Duffort, O; Calabozo, B; González, R; Carpizo, J A; Barber, D; Polo, F

2004-12-01

Pollen of Bermuda grass (Cynodon dactylon) is an important cause of pollinosis in many areas of the world. Most patients show sensitivity to the major allergen Cyn d 1, a glycoprotein composed of a number of isoforms with a molecular mass of 31-32 kDa. The aim of this work was to develop a monoclonal antibody (mAb)-based ELISA to quantify Cyn d 1, and to assess the correlation of the allergen content with the biological activity of C. dactylon pollen extracts. After fusion of myeloma cells with spleen cells from a BALB/c mouse immunized with C. dactylon pollen extract, Cyn d 1-specific mAbs secreting hybridomas were selected, and the antibodies characterized. One of them (4.4.1) was used as the capture antibody in an ELISA method for Cyn d 1 quantitation. An anti-Cyn d 1 rabbit serum was used as the second antibody. Cyn d 1 was purified by immunoaffinity chromatography with mAb 4.4.1, characterized, and used as the standard in the assay. The identity, purity and isoallergen composition of affinity-purified Cyn d 1 was confirmed by N-terminal amino acid sequencing, SDS-PAGE, Western blot and 2D electrophoresis. The Cyn d 1 ELISA is highly specific and sensitive, with a detection limit of 0.24 ng/ml and a linear range of 1.1-9.2 ng/ml. An excellent correlation was found when the content of Cyn d 1, measured in 16 different extracts, was compared with the allergenic activity of the same extracts determined by RAST inhibition. The results prove the usefulness of the Cyn d 1 ELISA for the standardization of C. dactylon-allergen products on the basis of major allergen content. 2004 S. Karger AG, Basel.

Staphylococcal enterotoxin A-activated regulatory T cells promote allergen-specific TH2 response to intratracheal allergen inoculation.

PubMed

Zeng, Wei-Ping; McFarland, Margaret M; Zhou, Baohua; Holtfreter, Silva; Flesher, Susan; Cheung, Ambrose; Mallick, Avishek

2017-02-01

T H 2 responses are implicated in asthma pathobiology. Epidemiologic studies have found a positive association between asthma and exposure to staphylococcal enterotoxins. We used a mouse model of asthma to determine whether staphylococcal enterotoxins promote T H 2 differentiation of allergen-specific CD4 conventional T (Tcon) cells and asthma by activating allergen-nonspecific regulatory T (Treg) cells to create a T H 2-polarizing cytokine milieu. Ovalbumin (OVA)-specific, staphylococcal enterotoxin A (SEA)-nonreactive naive CD4 Tcon cells were cocultured with SEA-reactive allergen-nonspecific Treg or CD4 Tcon cells in the presence of OVA and SEA. The OVA-specific CD4 T cells were then analyzed for IL-13 and IFN-γ expression. SEA-activated Treg cells were analyzed for the expression of the T H 2-polarizing cytokine IL-4 and the T-cell activation markers CD69 and CD62L. For asthma induction, mice were intratracheally sensitized with OVA or cat dander extract (CDE) alone or together with SEA and then challenged with OVA or CDE. Mice were also subject to transient Treg cell depletion before sensitization with OVA plus SEA. Asthma features and T H 2 differentiation in these mice were analyzed. SEA-activated Treg cells induced IL-13 but suppressed IFN-γ expression in OVA-specific CD4 Tcon cells. SEA-activated Treg cells expressed IL-4, upregulated CD69, and downregulated CD62L. Sensitization with OVA plus SEA but not OVA alone induced asthma, and SEA exacerbated asthma induced by CDE. Depletion of Treg cells abolished these effects of SEA and IL-13 expression in OVA-specific T cells. SEA promoted T H 2 responses of allergen-specific T cells and asthma pathogenesis by activating Treg cells. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Environmental triggers and avoidance in the management of asthma

PubMed Central

Gautier, Clarisse; Charpin, Denis

2017-01-01

Identifying asthma triggers forms the basis of environmental secondary prevention. These triggers may be allergenic or nonallergenic. Allergenic triggers include indoor allergens, such as house dust mites (HDMs), molds, pets, cockroaches, and rodents, and outdoor allergens, such as pollens and molds. Clinical observations provide support for the role of HDM exposure as a trigger, although avoidance studies provide conflicting results. Molds and their metabolic products are now considered to be triggers of asthma attacks. Pets, dogs, and especially cats can undoubtedly trigger asthmatic symptoms in sensitized subjects. Avoidance is difficult and rarely adhered to by families. Cockroach allergens contribute to asthma morbidity, and avoidance strategies can lead to clinical benefit. Mouse allergens are mostly found in inner-city dwellings, but their implication in asthma morbidity is debated. In the outdoors, pollens can induce seasonal asthma in sensitized individuals. Avoidance relies on preventing pollens from getting into the house and on minimizing seasonal outdoor exposure. Outdoor molds may lead to severe asthma exacerbations. Nonallergenic triggers include viral infections, active and passive smoking, meteorological changes, occupational exposures, and other triggers that are less commonly involved. Viral infection is the main asthma trigger in children. Active smoking is associated with higher asthma morbidity, and smoking cessation interventions should be personalized. Passive smoking is also a risk factor for asthma exacerbation. The implementation of public smoking bans has led to a reduction in the hospitalization of asthmatic children. Air pollution levels have been linked with asthmatic symptoms, a decrease in lung function, and increased emergency room visits and hospitalizations. Since avoidance is not easy to achieve, clean air policies remain the most effective strategy. Indoor air is also affected by air pollutants, such as cigarette smoke and volatile organic compounds generated by building and cleaning materials. Occupational exposures include work-exacerbated asthma and work-related asthma. PMID:28331347

Investigations of immunogenic, allergenic and adjuvant properties of Cry1Ab protein after intragastric exposure in a food allergy model in mice.

PubMed

Andreassen, Monica; Bøhn, Thomas; Wikmark, Odd-Gunnar; Bodin, Johanna; Traavik, Terje; Løvik, Martinus; Nygaard, Unni Cecilie

2016-05-04

In genetically modified (GM) crops there is a risk that the inserted genes may introduce new allergens and/or adjuvants into the food and feed chain. The MON810 maize, expressing the insecticidal Cry1Ab toxin, is grown in many countries worldwide. In animal models, intranasal and intraperitoneal immunisations with the purified Cry1Ab proteins have induced immune responses, and feeding trials with Cry1Ab-containing feed have revealed some altered immune responses. Previous investigations have primarily measured antibody responses to the protein, while investigations of clinical food allergy symptoms, or allergy promotion (adjuvant effect) associated with the Cry1Ab protein are largely missing. We aimed to investigate immunogenic, allergenic and adjuvant properties of purified Cry1Ab toxin (trypCry1Ab, i.e., trypsin activated Cry1Ab) in a mouse model of food allergy. Female C3H/HeJ mice were immunized by intragastric gavage of 10 μg purified, trypsin activated Cry1Ab toxin (trypCry1Ab) alone or together with the food allergen lupin. Cholera toxin was added as a positive control for adjuvant effect to break oral tolerance. Clinical symptoms (anaphylaxis) as well as humoral and cellular responses were assessed. In contrast to results from previous airway investigations, we observed no indication of immunogenic properties of trypCry1Ab protein after repeated intragastric exposures to one dose, with or without CT as adjuvant. Moreover, the results indicated that trypCry1Ab given by the intragastric route was not able to promote allergic responses or anaphylactic reactions against the co-administered allergen lupin at the given dose. The study suggests no immunogenic, allergenic or adjuvant capacity of the given dose of trypCry1Ab protein after intragastric exposure of prime aged mice.

Mimotopes for Api g 5, a Relevant Cross-reactive Allergen, in the Celery-Mugwort-Birch-Spice Syndrome.

PubMed

Lukschal, Anna; Wallmann, Julia; Bublin, Merima; Hofstetter, Gerlinde; Mothes-Luksch, Nadine; Breiteneder, Heimo; Pali-Schöll, Isabella; Jensen-Jarolim, Erika

2016-03-01

In the celery-mugwort-birch-spice syndrome, a significant proportion of IgE is directed against high molecular weight (HMW) glycoproteins, including the celery allergen Api g 5. BIP3, a monoclonal antibody originally raised against birch pollen, recognizes HMW allergens in birch and mugwort pollens, celery, and Apiaceae spices. Our aim was to generate mimotopes using BIP3 for immunization against the HMW allergens relevant in the celery-mugwort-birch-spice cross reactivity syndrome. Mimotopes were selected from a random-peptide display library by BIP3 and applied in IgE inhibition assays. The 3 phage clones with the highest inhibitory capacity were chosen for immunization of BALB/c mice. Mouse immune sera were tested for IgG binding to blotted birch pollen extract and used for inhibiting patients' IgE binding. Furthermore, sera were tested for binding to Api g 5, to horseradish peroxidase (HRP) as a second glycoprotein, or to non-glycosylated control allergen Phl p 5 in ELISA, and the specific Api g 5-specific IgG titers were determined. Three rounds of biopanning resulted in phage clones exhibiting 7 different sequences including 1 dominant, 1-6-cyclo-CHKLRCDKAIA. Three phage clones had the capacity to inhibit human IgE binding and induced IgG to the HMW antigen when used for immunizing BALB/c mice. The induced BIP3-mimotope IgG reached titers of 1:500 specifically to Api g 5, but hardly reacted to glycoprotein HRP, revealing a minor role of carbohydrates in their epitope. The mimotopes characterized in this study mimic the epitope of BIP3 relevant for Api g 5, one of the cross-reactive HMW allergens relevant in the celery-mugwort-birch-spice syndrome. BIP3 mimotopes may be used in the future for hyposensitization in this clinical syndrome by virtue of good and specific immunogenicity.

Building characteristics affect the risk of allergy development.

PubMed

Hesselmar, Bill; Aberg, Birgitta; Eriksson, Bo; Björkstén, Bengt; Aberg, Nils

2005-03-01

Damp dwellings increase the risk for house dust mite (HDM) infestation in temperate climate zones and may be associated with an increased risk for allergic disease. The aim of the study was to assess possible relationships between allergen levels in house dust, characteristics of residence buildings and allergic diseases in children. A subsample of 12-yr-old children, having the same address in 1991 and 1996, was selected from a population-based sample of children from the Göteborg area. Health inspectors examined the residences of all the 109 children and several different building characteristics including humidity and indoor temperature were collected. Dust samples for analysis of HDM allergens were collected from the children's beds, and for analysis of cat and dog allergens from the living room. Current health status was assessed by questionnaires, interviews and skin prick tests (SPT). Dog or cat allergens were found in all houses, even in houses without such animals. HDM allergens were found in 60% of the houses, but only six of them had levels exceeding 2 microg/g dust. There was a strong association between HDM-infestation and wheeze, but not with specific sensitization to HDM. The type of building (houses when compared with flats), the ventilation system and the presence of a basement had all major implications on respiratory symptoms, atopy and HDM infestation. We can conclude that dog or cat allergens were found in all houses, and a strong association between HDM infestation and indoor environment. Building construction affected both respiratory morbidity and sensitisation independently, suggesting not only worsening of symptoms but also a causative relationship with disease development. Copyright (c) 2005 Blackwell Munksgaard

Mechanisms underlying differential food allergy response to heated egg.

PubMed

Martos, Gustavo; Lopez-Exposito, Ivan; Bencharitiwong, Ramon; Berin, M Cecilia; Nowak-Węgrzyn, Anna

2011-04-01

Egg white proteins are usually subjected to heating, making them edible for the majority of children with egg allergy. We sought to investigate the underlying mechanisms responsible for the reduced allergenicity displayed by heat-treated egg white allergens. C3H/HeJ mice were orally sensitized with ovalbumin (OVA) or ovomucoid and challenged with native or heated proteins to evaluate their allergenicity. Immunoreactivity was assessed by immunoblotting using sera from children with egg allergy. In vitro gastrointestinal digestion of native and heated OVA and ovomucoid was studied by SDS-PAGE and liquid chromatography. Intestinal uptake of intact native and heated OVA and ovomucoid by human intestinal epithelial (Caco-2) cells was investigated. Rat basophil leukemia cells passively sensitized with mouse serum and human basophils passively sensitized with serum from children with egg allergy were used to assess the effector cell activation by heated, digested, and transported OVA and ovomucoid. Heated OVA and ovomucoid did not induce symptoms of anaphylaxis in sensitized mice when administered orally. Heating did not completely destroy IgE-binding capacity of OVA or ovomucoid but enhanced in vitro digestibility of OVA. Digestion of both OVA and ovomucoid diminished mediator release in rat basophil leukemia assay and basophil activation. Heating of allergens prevented transport across human intestinal epithelial cells in a form capable of triggering basophil activation or T-cell activation. Heat treatment reduces allergenicity of OVA and ovomucoid. This is partially a result of the enhanced gastrointestinal digestibility of heated OVA and the inability of heated OVA or ovomucoid to be absorbed in a form capable of triggering basophils. Copyright © 2011 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Modulation of allergic immune responses by mucosal application of recombinant lactic acid bacteria producing the major birch pollen allergen Bet v 1.

PubMed

Daniel, C; Repa, A; Wild, C; Pollak, A; Pot, B; Breiteneder, H; Wiedermann, U; Mercenier, A

2006-07-01

Probiotic lactic acid bacteria (LAB) are able to modulate the host immune system and clinical trials have demonstrated that specific strains have the capacity to reduce allergic symptoms. Therefore, we aimed to evaluate the potential of recombinant LAB producing the major birch pollen allergen Bet v 1 for mucosal vaccination against birch pollen allergy. Recombinant Bet v 1-producing Lactobacillus plantarum and Lactococcus lactis strains were constructed. Their immunogenicity was compared with purified Bet v 1 by subcutaneous immunization of mice. Intranasal application of the live recombinant strains was performed to test their immunomodulatory potency in a mouse model of birch pollen allergy. Bet v 1 produced by the LAB was recognized by monoclonal anti-Bet v 1 and IgE antibodies from birch pollen-allergic patients. Systemic immunization with the recombinant strains induced significantly lower IgG1/IgG2a ratios compared with purified Bet v 1. Intranasal pretreatment led to reduced allergen-specific IgE vs enhanced IgG2a levels and reduced interleukin (IL)-5 production of splenocytes in vitro, indicating a shift towards non-allergic T-helper-1 (Th1) responses. Airway inflammation, i.e. eosinophils and IL-5 in lung lavages, was reduced using either Bet v 1-producing or control strains. Allergen-specific secretory IgA responses were enhanced in lungs and intestines after pretreatment with only the Bet v 1-producing strains. Mucosal vaccination with live recombinant LAB, leading to a shift towards non-allergic immune responses along with enhanced allergen-specific mucosal IgA levels offers a promising approach to prevent systemic and local allergic immune responses.

Janus-faced Acrolein prevents allergy but accelerates tumor growth by promoting immunoregulatory Foxp3+ cells: Mouse model for passive respiratory exposure.

PubMed

Roth-Walter, Franziska; Bergmayr, Cornelia; Meitz, Sarah; Buchleitner, Stefan; Stremnitzer, Caroline; Fazekas, Judit; Moskovskich, Anna; Müller, Mario A; Roth, Georg A; Manzano-Szalai, Krisztina; Dvorak, Zdenek; Neunkirchner, Alina; Jensen-Jarolim, Erika

2017-03-23

Acrolein, a highly reactive unsaturated aldehyde, is generated in large amounts during smoking and is best known for its genotoxic capacity. Here, we aimed to assess whether acrolein at concentrations relevant for smokers may also exert immunomodulatory effects that could be relevant in allergy or cancer. In a BALB/c allergy model repeated nasal exposure to acrolein abrogated allergen-specific antibody and cytokine formation, and led to a relative accumulation of regulatory T cells in the lungs. Only the acrolein-treated mice were protected from bronchial hyperreactivity as well as from anaphylactic reactions upon challenge with the specific allergen. Moreover, grafted D2F2 tumor cells grew faster and intratumoral Foxp3+ cell accumulation was observed in these mice compared to sham-treated controls. Results from reporter cell lines suggested that acrolein acts via the aryl-hydrocarbon receptor which could be inhibited by resveratrol and 3'-methoxy-4'-nitroflavone Acrolein- stimulation of human PBMCs increased Foxp3+ expression by T cells which could be antagonized by resveratrol. Our mouse and human data thus revealed that acrolein exerts systemic immunosuppression by promoting Foxp3+ regulatory cells. This provides a novel explanation why smokers have a lower allergy, but higher cancer risk.

Proliferative responses in the local lymph node assay associated with concomitant exposure to 1,4-phenylenediamine and methyldibromo glutaronitrile: evidence for synergy?

PubMed

Jowsey, Ian R; Basketter, David A; Irwin, Anita

2008-08-01

A key consideration when undertaking risk assessments should be the potential for synergy between contact allergens. Previously, this concept has only been investigated during elicitation in contact allergic individuals. To determine whether there exists evidence for synergy between contact allergens during the induction phase of skin sensitization using the mouse local lymph node assay (LLNA) as a model system. Proliferative responses in draining lymph nodes were assessed with increasing concentrations of 1,4-phenylenediamine (PPD), methyldibromo glutaronitrile (MDBGN), and a combination of PPD and MDBGN. Data from each of two independent experiments show that lymph node cell proliferation associated with combined exposure to PPD and MDBGN was, in general, only modestly increased relative to that predicted from a simple summation of their individual responses. Although the increase in response is very modest, it does imply a relationship between this combination of sensitizers that may not be simply additive in terms of their ability to stimulate proliferative responses in draining lymph nodes. The reproducibility of this observation should be confirmed in future studies with additional pairs of contact allergens to ascertain whether or not this represents evidence of synergy.

S-Nitrosoglutathione Reductase Inhibition Regulates Allergen-Induced Lung Inflammation and Airway Hyperreactivity

PubMed Central

Bassett, David J. P.; Bradley, Matthews O.; Jaffar, Zeina

2013-01-01

Allergic asthma is characterized by Th2 type inflammation, leading to airway hyperresponsivenes, mucus hypersecretion and tissue remodeling. S-Nitrosoglutathione reductase (GSNOR) is an alcohol dehydrogenase involved in the regulation of intracellular levels of S-nitrosothiols. GSNOR activity has been shown to be elevated in human asthmatic lungs, resulting in diminished S-nitrosothiols and thus contributing to increased airway hyperreactivity. Using a mouse model of allergic airway inflammation, we report that intranasal administration of a new selective inhibitor of GSNOR, SPL-334, caused a marked reduction in airway hyperreactivity, allergen-specific T cells and eosinophil accumulation, and mucus production in the lungs in response to allergen inhalation. Moreover, SPL-334 treatment resulted in a significant decrease in the production of the Th2 cytokines IL-5 and IL-13 and the level of the chemokine CCL11 (eotaxin-1) in the airways. Collectively, these observations reveal that GSNOR inhibitors are effective not only in reducing airway hyperresponsiveness but also in limiting lung inflammatory responses mediated by CD4+ Th2 cells. These findings suggest that the inhibition of GSNOR may provide a novel therapeutic approach for the treatment of allergic airway inflammation. PMID:23936192

Association of Roadway Proximity with Indoor Air Pollution in a Peri-Urban Community in Lima, Peru

PubMed Central

Underhill, Lindsay J.; Bose, Sonali; Williams, D’Ann L.; Romero, Karina M.; Malpartida, Gary; Breysse, Patrick N.; Klasen, Elizabeth M.; Combe, Juan M.; Checkley, William; Hansel, Nadia N.

2015-01-01

The influence of traffic-related air pollution on indoor residential exposure is not well characterized in homes with high natural ventilation in low-income countries. Additionally, domestic allergen exposure is unknown in such populations. We conducted a pilot study of 25 homes in peri-urban Lima, Peru to estimate the effects of roadway proximity and season on residential concentrations. Indoor and outdoor concentrations of particulate matter (PM2.5), nitrogen dioxide (NO2), and black carbon (BC) were measured during two seasons, and allergens were measured in bedroom dust. Allergen levels were highest for dust mite and mouse allergens, with concentrations above clinically relevant thresholds in over a quarter and half of all homes, respectively. Mean indoor and outdoor pollutant concentrations were similar (PM2.5: 20.0 vs. 16.9 μg/m3, BC: 7.6 vs. 8.1 μg/m3, NO2: 7.3 vs. 7.5 ppb), and tended to be higher in the summer compared to the winter. Road proximity was significantly correlated with overall concentrations of outdoor PM2.5 (rs = −0.42, p = 0.01) and NO2 (rs = −0.36, p = 0.03), and outdoor BC concentrations in the winter (rs = −0.51, p = 0.03). Our results suggest that outdoor-sourced pollutants significantly influence indoor air quality in peri-urban Peruvian communities, and homes closer to roadways are particularly vulnerable. PMID:26516875

Comparative immunology of allergic responses.

PubMed

Gershwin, Laurel J

2015-01-01

Allergic responses occur in humans, rodents, non-human primates, avian species, and all of the domestic animals. These responses are mediated by immunoglobulin E (IgE) antibodies that bind to mast cells and cause release/synthesis of potent mediators. Clinical syndromes include naturally occurring asthma in humans and cats; atopic dermatitis in humans, dogs, horses, and several other species; food allergies; and anaphylactic shock. Experimental induction of asthma in mice, rats, monkeys, sheep, and cats has helped to reveal mechanisms of pathogenesis of asthma in humans. All of these species share the ability to develop a rapid and often fatal response to systemic administration of an allergen--anaphylactic shock. Genetic predisposition to development of allergic disease (atopy) has been demonstrated in humans, dogs, and horses. Application of mouse models of IgE-mediated allergic asthma has provided evidence for a role of air pollutants (ozone, diesel exhaust, environmental tobacco smoke) in enhanced sensitization to allergens.

Dual-color STED microscopy reveals a sandwich structure of Bassoon and Piccolo in active zones of adult and aged mice.

PubMed

Nishimune, Hiroshi; Badawi, Yomna; Mori, Shuuichi; Shigemoto, Kazuhiro

2016-06-20

Presynaptic active zones play a pivotal role as synaptic vesicle release sites for synaptic transmission, but the molecular architecture of active zones in mammalian neuromuscular junctions (NMJs) at sub-diffraction limited resolution remains unknown. Bassoon and Piccolo are active zone specific cytosolic proteins essential for active zone assembly in NMJs, ribbon synapses, and brain synapses. These proteins are thought to colocalize and share some functions at active zones. Here, we report an unexpected finding of non-overlapping localization of these two proteins in mouse NMJs revealed using dual-color stimulated emission depletion (STED) super resolution microscopy. Piccolo puncta sandwiched Bassoon puncta and aligned in a Piccolo-Bassoon-Piccolo structure in adult NMJs. P/Q-type voltage-gated calcium channel (VGCC) puncta colocalized with Bassoon puncta. The P/Q-type VGCC and Bassoon protein levels decreased significantly in NMJs from aged mouse. In contrast, the Piccolo levels in NMJs from aged mice were comparable to levels in adult mice. This study revealed the molecular architecture of active zones in mouse NMJs at sub-diffraction limited resolution, and described the selective degeneration mechanism of active zone proteins in NMJs from aged mice. Interestingly, the localization pattern of active zone proteins described herein is similar to active zone structures described using electron microscope tomography.

Inhibition of neutrophil elastase attenuates airway hyperresponsiveness and inflammation in a mouse model of secondary allergen challenge: neutrophil elastase inhibition attenuates allergic airway responses

PubMed Central

2013-01-01

Background Chronic asthma is often associated with neutrophilic infiltration in the airways. Neutrophils contain elastase, a potent secretagogue in the airways, nonetheless the role for neutrophil elastase as well as neutrophilic inflammation in allergen-induced airway responses is not well defined. In this study, we have investigated the impact of neutrophil elastase inhibition on the development of allergic airway inflammation and airway hyperresponsiveness (AHR) in previously sensitized and challenged mice. Methods BALB/c mice were sensitized and challenged (primary) with ovalbumin (OVA). Six weeks later, a single OVA aerosol (secondary challenge) was delivered and airway inflammation and airway responses were monitored 6 and 48 hrs later. An inhibitor of neutrophil elastase was administered prior to secondary challenge. Results Mice developed a two-phase airway inflammatory response after secondary allergen challenge, one neutrophilic at 6 hr and the other eosinophilic, at 48 hr. PAR-2 expression in the lung tissues was enhanced following secondary challenge, and that PAR-2 intracellular expression on peribronchial lymph node (PBLN) T cells was also increased following allergen challenge of sensitized mice. Inhibition of neutrophil elastase significantly attenuated AHR, goblet cell metaplasia, and inflammatory cell accumulation in the airways following secondary OVA challenge. Levels of IL-4, IL-5 and IL-13, and eotaxin in BAL fluid 6 hr after secondary allergen challenge were significantly suppressed by the treatment. At 48 hr, treatment with the neutrophil elastase inhibitor significantly reduced the levels of IL-13 and TGF-β1 in the BAL fluid. In parallel, in vitro IL-13 production was significantly inhibited in spleen cells from sensitized mice. Conclusion These data indicate that neutrophil elastase plays an important role in the development of allergic airway inflammation and hyperresponsiveness, and would suggest that the neutrophil elastase inhibitor reduced AHR to inhaled methacholine indicating the potential for its use as a modulator of the immune/inflammatory response in both the neutrophil- and eosinophil-dominant phases of the response to secondary allergen challenge. PMID:23347423

In vivo and in vitro immunomodulation of Der p 1 allergen-specific response by Lactobacillus plantarum bacteria.

PubMed

Hisbergues, M; Magi, M; Rigaux, P; Steuve, J; Garcia, L; Goudercourt, D; Pot, B; Pestel, J; Jacquet, A

2007-09-01

Lactic acid bacteria (LAB) were reported to reduce some allergic manifestations in mice and humans but their impact on the aeroallergen-dependent immune mechanisms is still debated. The potential capacities of Lactobacillus plantarum NCIMB8826 to reduce the allergic response induced by Der p 1, the major house dust mite allergen of Dermatophagoides pteronyssinus, were evaluated in vivo and in vitro. Methods First, the effect of the intranasal co-administration of LAB and purified Der p 1 allergen before a sensitization protocol was evaluated. The allergen-specific antibody and cellular responses as well as airway inflammation were measured. Second, the impact of LAB on the cytokine profile of spleens cells from Der p 1-sensitized mice was assessed. Third, upon stimulation with LAB, the levels of cytokine produced by dendritic cells derived from the bone marrow (BMDCs) of wild-type, Toll-like receptor 2 (TLR2)-, TLR4- and MyD88-KO mice were compared. Results The co-application of L. plantarum and Der p 1 induced a T-helper type 1 (Th1)-biased allergen-specific IgG response, the absence of specific IgE response and favoured the production of INF-gamma upon allergen re-stimulation. Moreover, the previous LAB administration reduced the development of bronchoalveolar lavage eosinophilia usually induced by aerosol exposure. Additionally, the studied LAB strain was shown to modify in vitro the cytokine level produced by Der p 1-sensitized spleen cells mainly towards a Th1 profile. Finally, L. plantarum stimulated high IL-12 and moderate IL-10 production in mouse BMDCs notably through the TLR2-, MyD88-dependent and TLR4-independent pathway. In vivo co-administration of probiotic LAB with Der p 1 might prevent the development of the mite allergic response. The probiotic L. plantarum was shown to display in vitro therapeutic potentials for the treatment of allergy and to trigger the immune system by a TLR2- and MyD88-dependent signalling pathway.

Anti-inflammatory and immune-regulatory mechanisms prevent contact hypersensitivity to Arnica montana L.

PubMed

Lass, Christian; Vocanson, Marc; Wagner, Steffen; Schempp, Christoph M; Nicolas, Jean-Francois; Merfort, Irmgard; Martin, Stefan F

2008-10-01

Sesquiterpene lactones (SL), secondary plant metabolites from flowerheads of Arnica, exert anti-inflammatory effects mainly by preventing nuclear factor (NF)-kappaB activation because of alkylation of the p65 subunit. Despite its known immunosuppressive action, Arnica has been classified as a plant with strong potency to induce allergic contact dermatitis. Here we examined the dual role of SL as anti-inflammatory compounds and contact allergens in vitro and in vivo. We tested the anti-inflammatory and allergenic potential of SL in the mouse contact hypersensitivity model. We also used dendritic cells to study the activation of NF-kappaB and the secretion of interleukin (IL)-12 in the presence of different doses of SL in vitro. Arnica tinctures and SL potently suppressed NF-kappaB activation and IL-12 production in dendritic cells at high concentrations, but had immunostimulatory effects at low concentrations. Contact hypersensitivity could not be induced in the mouse model, even when Arnica tinctures or SL were applied undiluted to inflamed skin. In contrast, Arnica tinctures suppressed contact hypersensitivity to the strong contact sensitizer trinitrochlorobenzene and activation of dendritic cells. However, contact hypersensitivity to Arnica tincture could be induced in acutely CD4-depleted MHC II knockout mice. These results suggest that induction of contact hypersensitivity by Arnica is prevented by its anti-inflammatory effect and immunosuppression as a result of immune regulation in immunocompetent mice.

Heat-Induced Structural Changes Affect OVA-Antigen Processing and Reduce Allergic Response in Mouse Model of Food Allergy

PubMed Central

Wallner, Michael; Kverka, Miloslav; Kozakova, Hana; Srutkova, Dagmar; Klimesova, Klara; Sotkovsky, Petr; Palova-Jelinkova, Lenka; Ferreira, Fatima; Tuckova, Ludmila

2012-01-01

Background and Aims The egg protein ovalbumin (OVA) belongs to six most frequent food allergens. We investigated how thermal processing influences its ability to induce allergic symptoms and immune responses in mouse model of food allergy. Methodology/Principal Findings Effect of increased temperature (70°C and 95°C) on OVA secondary structure was characterized by circular dichroism and by the kinetics of pepsin digestion with subsequent HPLC. BALB/c mice were sensitized intraperitoneally and challenged with repeated gavages of OVA or OVA heated to 70°C (h-OVA). Levels of allergen-specific serum antibodies were determined by ELISA (IgA and IgGs) or by β-hexosaminidase release test (IgE). Specific activities of digestive enzymes were determined in brush border membrane vesicles of jejunal enterocytes. Cytokine production and changes in regulatory T cells in mesenteric lymph nodes and spleen were assessed by ELISA and FACS. Heating of OVA to 70°C caused mild irreversible changes in secondary structure compared to boiling to 95°C (b-OVA), but both OVA treatments led to markedly different digestion kinetics and Tregs induction ability in vitro, compared to native OVA. Heating of OVA significantly decreased clinical symptoms (allergic diarrhea) and immune allergic response on the level of IgE, IL-4, IL-5, IL-13. Furthermore, h-OVA induced lower activities of serum mast cell protease-1 and enterocyte brush border membrane alkaline phosphatase as compared to native OVA. On the other hand h-OVA stimulated higher IgG2a in sera and IFN-γ secretion by splenocytes. Conclusions Minor irreversible changes in OVA secondary structure caused by thermal processing changes both its digestion and antigenic epitopes formation, which leads to activation of different T cell subpopulations, induces shift towards Th1 response and ultimately reduces its allergenicity. PMID:22629361

Up-regulated expression of substance P in CD8+ T cells and NK1R on monocytes of atopic dermatitis.

PubMed

Zhang, Zenan; Zheng, Wenjiao; Xie, Hua; Chai, Ruonan; Wang, Junling; Zhang, Huiyun; He, Shaoheng

2017-05-01

Large numbers of CD8 + T cells were observed in atopic dermatitis (AD) skin, and monocytes from AD patients showed increased prostaglandin E2 production. However, little is known about the expression of substance P (SP) and its receptor NK1R in blood leukocytes of patients with AD. To explore the expression of SP and NK1R in leukocytes of AD and the influence of allergens on SP and NK1R expression. The expression levels of SP and NK1R in patients with AD were examined by flow cytometry, ELISA and a mouse AD model. The plasma SP level was 4.9-fold higher in patients with AD than in HC subjects. Both the percentage of SP expression in the population and mean fluorescence intensity (MFI) of SP expression were elevated in CD8 + T cells in the blood of AD patients. However, both the CD14 + NK1R + population and MFI of NK1R expression on CD14 + cells were enhanced in the blood of AD patients. Allergens ASWE, HDME and PPE failed to up-regulate SP expression in CD8 + T cells. However, allergens ASWE and HDME both enhanced NK1R expression on CD14 + blood leukocytes regardless of AD or HC subjects. OVA-sensitized AD mice showed an elevated proportion and MFI of SP-expressing CD8 + T cells in the blood, which agrees with the SP expression situation in human AD blood. Injection of SP into mouse skin did not up-regulate NK1R expression on monocytes. An elevated plasma SP level, up-regulated expression of SP and NK1R indicate that the SP/NK1R complex is important in the development of AD. Therefore, SP and NK1R antagonist or blocker agents may help to treat patients with AD. Trial registration Registration number: ChiCTR-BOC-16010279; Registration date: Dec., 28, 2016; retrospectively registered.

1alpha,25-dihydroxyvitamin D3 potentiates the beneficial effects of allergen immunotherapy in a mouse model of allergic asthma: role for IL-10 and TGF-beta.

PubMed

Taher, Yousef A; van Esch, Betty C A M; Hofman, Gerard A; Henricks, Paul A J; van Oosterhout, Antoon J M

2008-04-15

1alpha,25-Dihydroxyvitamin D(3) (1,25(OH)(2)D(3)), a potent inhibitor of NF-kappaB expression, can prevent the maturation of dendritic cells in vitro leading to tolerogenic dendritic cells with increased potential to induce regulatory T cells. Herein, we investigated whether the combination of allergen immunotherapy with 1,25(OH)(2)D(3) potentiates the suppressive effects of immunotherapy and whether the immunoregulatory cytokines IL-10 and TGF-beta are involved in the effector phase. OVA-sensitized and challenged BALB/c mice displayed airway hyperresponsiveness (AHR) and increased serum OVA-specific IgE levels, bronchoalveolar lavage eosinophilia, and Th2 cytokine levels. In this model, the dose response of allergen immunotherapy 10 days before OVA inhalation challenge shows strong suppression of asthma manifestations at 1 mg of OVA, but partial suppression of bronchoalveolar lavage eosinophilia, IgE up-regulation, and no reduction of AHR at 100 microg. Interestingly, coadministration of 10 ng of 1,25(OH)(2)D(3) with 100 microg of OVA immunotherapy significantly inhibited AHR and potentiated the reduction of serum OVA-specific IgE levels, airway eosinophilia, and Th2-related cytokines concomitant with increased IL-10 levels in lung tissues and TGF-beta and OVA-specific IgA levels in serum. Similar effects on suboptimal immunotherapy were observed by inhibition of the NF-kappaB pathway using the selective IkappaB kinase 2 inhibitor PS-1145. The suppressive effects of this combined immunotherapy were partially reversed by treatment with mAb to either IL-10R or TGF-beta before OVA inhalation challenge but completely abrogated when both Abs were given. These data demonstrate that 1,25(OH)(2)D(3) potentiates the efficacy of immunotherapy and that the regulatory cytokines IL-10 and TGF-beta play a crucial role in the effector phase of this mouse model.

Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods

PubMed Central

Tovey, Euan R.; Liu-Brennan, Damien; Garden, Frances L.; Oliver, Brian G.; Perzanowski, Matthew S.; Marks, Guy B.

2016-01-01

Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical development and clinical applications. PMID:27192200

Time-Based Measurement of Personal Mite Allergen Bioaerosol Exposure over 24 Hour Periods.

PubMed

Tovey, Euan R; Liu-Brennan, Damien; Garden, Frances L; Oliver, Brian G; Perzanowski, Matthew S; Marks, Guy B

2016-01-01

Allergic diseases such as asthma and rhinitis are common in many countries. Globally the most common allergen associated with symptoms is produced by house dust mites. Although the bed has often been cited as the main site of exposure to mite allergens, surprisingly this has not yet been directly established by measurement due to a lack of suitable methods. Here we report on the development of novel methods to determine the pattern of personal exposure to mite allergen bioaerosols over 24-hour periods and applied this in a small field study using 10 normal adults. Air was sampled using a miniature time-based air-sampler of in-house design located close to the breathing zone of the participants, co-located with a miniature time-lapse camera. Airborne particles, drawn into the sampler at 2L/min via a narrow slot, were impacted onto the peripheral surface of a disk mounted on the hour-hand of either a 12 or 24 hour clock motor. The impaction surface was either an electret cloth, or an adhesive film; both novel for these purposes. Following a review of the time-lapse images, disks were post-hoc cut into subsamples corresponding to eight predetermined categories of indoor or outdoor location, extracted and analysed for mite allergen Der p 1 by an amplified ELISA. Allergen was detected in 57.2% of the total of 353 subsamples collected during 20 days of sampling. Exposure patterns varied over time. Higher concentrations of airborne mite allergen were typically measured in samples collected from domestic locations in the day and evening. Indoor domestic Der p 1 exposures accounted for 59.5% of total exposure, whereas total in-bed-asleep exposure, which varied 80 fold between individuals, accounted overall for 9.85% of total exposure, suggesting beds are not often the main site of exposure. This study establishes the feasibility of novel methods for determining the time-geography of personal exposure to many bioaerosols and identifies new areas for future technical development and clinical applications.

Lifelong memory responses perpetuate humoral TH2 immunity and anaphylaxis in food allergy.

PubMed

Jiménez-Saiz, Rodrigo; Chu, Derek K; Mandur, Talveer S; Walker, Tina D; Gordon, Melissa E; Chaudhary, Roopali; Koenig, Joshua; Saliba, Sarah; Galipeau, Heather J; Utley, Adam; King, Irah L; Lee, Kelvin; Ettinger, Rachel; Waserman, Susan; Kolbeck, Roland; Jordana, Manel

2017-12-01

A number of food allergies (eg, fish, shellfish, and nuts) are lifelong, without any disease-transforming therapies, and unclear in their underlying immunology. Clinical manifestations of food allergy are largely mediated by IgE. Although persistent IgE titers have been attributed conventionally to long-lived IgE + plasma cells (PCs), this has not been directly and comprehensively tested. We sought to evaluate mechanisms underlying persistent IgE and allergic responses to food allergens. We used a model of peanut allergy and anaphylaxis, various knockout mice, adoptive transfer experiments, and in vitro assays to identify mechanisms underlying persistent IgE humoral immunity over almost the entire lifespan of the mouse (18-20 months). Contrary to conventional paradigms, our data show that clinically relevant lifelong IgE titers are not sustained by long-lived IgE + PCs. Instead, lifelong reactivity is conferred by allergen-specific long-lived memory B cells that replenish the IgE + PC compartment. B-cell reactivation requires allergen re-exposure and IL-4 production by CD4 T cells. We define the half-lives of antigen-specific germinal centers (23.3 days), IgE + and IgG 1 + PCs (60 and 234.4 days, respectively), and clinically relevant cell-bound IgE (67.3 days). These findings can explain lifelong food allergies observed in human subjects as the consequence of allergen exposures that recurrently activate memory B cells and identify these as a therapeutic target with disease-transforming potential. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Animal models of protein allergenicity: potential benefits, pitfalls and challenges.

PubMed

Dearman, R J; Kimber, I

2009-04-01

Food allergy is an important health issue. With an increasing interest in novel foods derived from transgenic crop plants, there is a growing need for the development of approaches suitable for the characterization of the allergenic potential of proteins. There are methods available currently (such as homology searches and serological testing) that are very effective at identifying proteins that are likely to cross-react with known allergens. However, animal models may play a role in the identification of truly novel proteins, such as bacterial or fungal proteins, that have not been experienced previously in the diet. We consider here the potential benefits, pitfalls and challenges of the selection of various animal models, including the mouse, the rat, the dog and the neonatal swine. The advantages and disadvantages of various experimental end-points are discussed, including the measurement of specific IgE by ELISA, Western blotting or functional tests such as the passive cutaneous anaphylaxis assay, and the assessment of challenge-induced clinical symptoms in previously sensitized animals. The experimental variables of route of exposure to test proteins and the incorporation of adjuvant to increase the sensitivity of the responses are considered also. It is important to emphasize that currently none of these approaches has been validated for the purposes of hazard identification in the context of a safety assessment. However, the available evidence suggests that the judicious use of an accurate and robust animal model could provide important additional data that would contribute significantly to the assessment of the potential allergenicity of novel proteins.

Purification, cloning, and immunological characterization of arginine kinase, a novel allergen of Octopus fangsiao.

PubMed

Shen, Hai-Wang; Cao, Min-Jie; Cai, Qiu-Feng; Ruan, Mi-Mi; Mao, Hai-Yan; Su, Wen-Jin; Liu, Guang-Ming

2012-03-07

Arginine kinase (AK) is an important enzyme participating in energy metabolism in invertebrates, but, to date, there have been no reports that AK from octopus is an allergen. In this study, octopus AK was purified, and its molecular biological, immunological, and physicochemical characterizations were analyzed. The results showed that octopus AK was purified and confirmed by mass spectrometry for the first time, and its molecular mass was 38 kDa. The full-length gene sequence of octopus AK encompassed 1209 bp and was predicted to encode a protein with 348 amino acid residues. The homology of octopus AK and crustacean AK was about 54%, but the similarity between their three-dimensional structures was high. Octopus AK could react with mouse anti-shrimp AK and rabbit anti-crab AK polyclonal antibody singly. Octopus AK could also react with specific IgE of the sera from octopus-allergic patients effectively, whereas crab AK could inhibit the reaction between them. Finally, the IgE-binding activity of octopus AK could be reduced in the processes of thermal or acid-alkali treatment. In summary, AK was identified as a novel allergen in octopus, which had a sensitizing ability similar to that of crustacean AK. This is significant in allergy diagnosis and the treatment of octopus-allergic disorders.

Early-life exposure to combustion-derived particulate matter causes pulmonary immunosuppression

PubMed Central

Saravia, Jordy; You, Dahui; Thevenot, Paul; Lee, Greg I.; Shrestha, Bishwas; Lomnicki, Slawo; Cormier, Stephania A.

2013-01-01

Elevated levels of combustion-derived particulate matter (CDPM) are a risk factor for the development of lung diseases such as asthma. Studies have shown that CDPM exacerbates asthma, inducing acute lung dysfunction and inflammation; however, the impact of CDPM exposure on early immunological responses to allergens remains unclear. To determine the effects of early-life CDPM exposure on allergic asthma development in infants, we exposed infant mice to CDPM and then induced a mouse model of asthma using house dust mite (HDM) allergen. Mice exposed to CDPM+HDM failed to develop a typical asthma phenotype including airway hyperresponsiveness, Th2-inflammation, Muc5ac expression, eosinophilia, and HDM-specific Ig compared to HDM-exposed mice. Although HDM-specific IgE was attenuated, total IgE was two-fold higher in CDPM+HDM mice compared to HDM-mice. We further demonstrate that CDPM exposure during early life induced an immunosuppressive environment in the lung, concurrent with increases in tolerogenic dendritic cells and Tregs, resulting in suppression of Th2 responses. Despite having early immunosuppression, these mice develop severe allergic inflammation when challenged with allergen as adults. These findings demonstrate a mechanism whereby CDPM exposure modulates adaptive immunity, inducing specific-antigen tolerance while amplifying total IgE, and leading to a predisposition to develop asthma upon rechallenge later in life. PMID:24172848

A distinct microbiota composition is associated with protection from food allergy in an oral mouse immunization model

PubMed Central

Diesner, Susanne C.; Bergmayr, Cornelia; Pfitzner, Barbara; Assmann, Vera; Krishnamurthy, Durga; Starkl, Philipp; Endesfelder, David; Rothballer, Michael; Welzl, Gerhard; Rattei, Thomas; Eiwegger, Thomas; Szépfalusi, Zsolt; Fehrenbach, Heinz; Jensen-Jarolim, Erika; Hartmann, Anton

2017-01-01

In our mouse model, gastric acid-suppression is associated with antigen-specific IgE and anaphylaxis development. We repeatedly observed non-responder animals protected from food allergy. Here, we aimed to analyse reasons for this protection. Ten out of 64 mice, subjected to oral ovalbumin (OVA) immunizations under gastric acid-suppression, were non-responders without OVA-specific IgE or IgG1 elevation, indicating protection from allergy. In these non-responders, allergen challenges confirmed reduced antigen uptake and lack of anaphylactic symptoms, while in allergic mice high levels of mouse mast-cell protease-1 and a body temperature reduction, indicative for anaphylaxis, were determined. Upon OVA stimulation, significantly lower IL-4, IL-5, IL-10 and IL-13 levels were detected in non-responders, while IL-22 was significantly higher. Comparison of fecal microbiota revealed differences of bacterial communities on single bacterial Operational-Taxonomic-Unit level between the groups, indicating protection from food allergy being associated with a distinct microbiota composition in a non-responding phenotype in this mouse model. PMID:27789346

Mould-devouring mites differ in guanine excretion from dust-eating Acari, a possible error source in mite allergen exposure studies.

PubMed

Kort, H S; Schober, G; Koren, L G; Scharringa, J

1997-08-01

Measurement of guanine in dust proved a good assessment of mite allergen exposure. Exposure to mite allergens may lead to atopic inflictions. In a semi-natural test system the development of Dermatophagoides pteronyssinus (Trouessart) and Glycyphagus domesticus (De Geer), and the presence of their guanine excretion, was examined in a dust-soiled and mouldy environment. Mites were counted after heat-escape, and guanine was detected by means of capillary zone electrophoresis. For each species, 50 mites randomly taken, were inoculated on soiled test-surfaces of 10 x 10 cm. Rough wooden board, gypsum board, tufted carpet, and a self-made mattress representing wall surfaces and home-textiles, respectively, were used. Eight weeks after inoculation with mites only, the surfaces were all mould ridden, and mite and guanine measurements were taken. The Spearman rank correlation test and the Mann-Whitney U-test were used in statistical analysis. The confidence limit was set at 1%. Among the various test-surfaces, no differences were found regarding total mite numbers and amount of guanine present (P > 0.01). For the dust-eating mite D. pteronyssinus, total mite numbers correlated with the amount of guanine present (P = 0.002) on all inoculated surfaces, indicating feeding on the protein-rich dust. For the mould devouring mite G. domesticus, however, no such correlation was found (P = 0.72). Apparently, they mainly consumed fungal carbohydrates during this experiment. The allergological relevance of storage mites has been under discussion for the last 25 years. In humid homes, these mites will feed almost exclusively on fungi and may produce allergenic or irritating substances different from those arising on protein-rich laboratory media used in allergen extract production or present in carpets, bedding and furniture.

Quantitative trait locus mapping of genes associated with vacuolation in the adrenal X-zone of the DDD/Sgn inbred mouse

PubMed Central

2012-01-01

Background Adrenal gland of mice contains a transient zone between the adrenal cortex and the adrenal medulla: the X-zone. There are clear strain differences in terms of X-zone morphology. Nulliparous females of the inbred mouse DDD strain develop adrenal X-zones containing exclusively vacuolated cells, whereas females of the inbred mouse B6 strain develop X-zones containing only non-vacuolated cells. The X-zone vacuolation is a physiologic process associated with the X-zone degeneration and is tightly regulated by genetic factors. Identification of the genetic factors controlling such strain differences should help analyze the X-zone function. In this study, a quantitative trait locus (QTL) analysis for the extent of X-zone vacuolation was performed for two types of F2 female mice: F2Ay mice (F2 mice with the Ay allele) and F2 non-Ay mice (F2 mice without the Ay allele). These were produced by crossing B6 females and DDD.Cg-Ay males. DDD.Cg-Ay is a congenic mouse strain for the Ay allele at the agouti locus and is used for this study because a close association between the X-zone morphology and the agouti locus genotype has been suggested. The Ay allele is dominant and homozygous lethal; therefore, living Ay mice are invariably heterozygotes. Results Single QTL scans identified significant QTLs on chromosomes 1, 2, 6, and X for F2 non-Ay mice, and on chromosomes 2, 6, and 12 for F2Ay mice. The QTL on chromosome 2 was considered to be because of the agouti locus, which has been suggested to be associated with X-zone vacuolation. A significant QTL that interacted with the agouti locus was identified on chromosome 8. Conclusions The extent of X-zone vacuolation in DDD females was controlled by multiple genes with complex interactions. The murine X-zone is considered analogous structure to the human fetal zone. Therefore, the results of this study will aid in understanding function of not only of the X-zone but also of the human fetal zone. Identifying the genes responsible for the QTLs will be essential for understanding the molecular basis of X-zone function, which is currently unclear. PMID:23131041

Quantitative trait locus mapping of genes associated with vacuolation in the adrenal X-zone of the DDD/Sgn inbred mouse.

PubMed

Suto, Jun-Ichi

2012-11-06

Adrenal gland of mice contains a transient zone between the adrenal cortex and the adrenal medulla: the X-zone. There are clear strain differences in terms of X-zone morphology. Nulliparous females of the inbred mouse DDD strain develop adrenal X-zones containing exclusively vacuolated cells, whereas females of the inbred mouse B6 strain develop X-zones containing only non-vacuolated cells. The X-zone vacuolation is a physiologic process associated with the X-zone degeneration and is tightly regulated by genetic factors. Identification of the genetic factors controlling such strain differences should help analyze the X-zone function. In this study, a quantitative trait locus (QTL) analysis for the extent of X-zone vacuolation was performed for two types of F2 female mice: F2Ay mice (F2 mice with the Ay allele) and F2 non-Ay mice (F2 mice without the Ay allele). These were produced by crossing B6 females and DDD.Cg-Ay males. DDD.Cg-Ay is a congenic mouse strain for the Ay allele at the agouti locus and is used for this study because a close association between the X-zone morphology and the agouti locus genotype has been suggested. The Ay allele is dominant and homozygous lethal; therefore, living Ay mice are invariably heterozygotes. Single QTL scans identified significant QTLs on chromosomes 1, 2, 6, and X for F2 non-Ay mice, and on chromosomes 2, 6, and 12 for F2Ay mice. The QTL on chromosome 2 was considered to be because of the agouti locus, which has been suggested to be associated with X-zone vacuolation. A significant QTL that interacted with the agouti locus was identified on chromosome 8. The extent of X-zone vacuolation in DDD females was controlled by multiple genes with complex interactions. The murine X-zone is considered analogous structure to the human fetal zone. Therefore, the results of this study will aid in understanding function of not only of the X-zone but also of the human fetal zone. Identifying the genes responsible for the QTLs will be essential for understanding the molecular basis of X-zone function, which is currently unclear.

Targeted microRNA expression in dairy cattle directs production of β-lactoglobulin-free, high-casein milk

PubMed Central

Jabed, Anower; Wagner, Stefan; McCracken, Judi; Wells, David N.; Laible, Goetz

2012-01-01

Milk from dairy cows contains the protein β-lactoglobulin (BLG), which is not present in human milk. As it is a major milk allergen, we wished to decrease BLG levels in milk by RNAi. In vitro screening of 10 microRNAs (miRNAs), either individually or in tandem combinations, identified several that achieved as much as a 98% knockdown of BLG. One tandem construct was expressed in the mammary gland of an ovine BLG-expressing mouse model, resulting in 96% knockdown of ovine BLG in milk. Following this in vivo validation, we produced a transgenic calf, engineered to express these tandem miRNAs. Analysis of hormonally induced milk from this calf demonstrated absence of BLG and a concurrent increase of all casein milk proteins. The findings demonstrate miRNA–mediated depletion of an allergenic milk protein in cattle and validate targeted miRNA expression as an effective strategy to alter milk composition and other livestock traits. PMID:23027958

Indoor Environmental Exposures for Children with Asthma Enrolled in the HEAL Study, Post-Katrina New Orleans

PubMed Central

Chulada, Patricia C.; Kennedy, Suzanne; White, LuAnn; Wildfire, Jeremy; Cohn, Richard D.; Mitchell, Herman; Thornton, Eleanor; El-Dahr, Jane; Mvula, Mosanda M.; Sterling, Yvonne; Martin, William J.; Stephens, Kevin U.; Lichtveld, Maureen

2012-01-01

Background: Rain and flooding from Hurricane Katrina resulted in widespread growth of mold and bacteria and production of allergens in New Orleans, Louisiana, which may have led to increased exposures and morbidity in children with asthma. Objectives: The goal of the Head-off Environmental Asthma in Louisiana (HEAL) study was to characterize post-Katrina exposures to mold and allergens in children with asthma. Methods: The homes of 182 children with asthma in New Orleans and surrounding parishes were evaluated by visual inspection, temperature and moisture measurements, and air and dust sampling. Air was collected using vacuum-pump spore traps and analyzed for > 30 mold taxa using bright field microscopy. Dust was collected from the children’s beds and bedroom floors and analyzed for mouse (Mus m 1), dust mite (Der p 1), cockroach (Bla g 1), and mold (Alternaria mix) allergens using ELISA. Results: More than half (62%) of the children were living in homes that had been damaged by rain, flooding, or both. Geometric mean indoor and outdoor airborne mold levels were 501 and 3,958 spores/m3, respectively. Alternaria antigen was detected in dust from 98% of homes, with 58% having concentrations > 10 µg/g. Mus m 1, Der p 1, and Bla g 1 were detected in 60%, 35%, and 20% of homes, respectively, at low mean concentrations. Conclusions: Except for Alternaria antigen in dust, concentrations of airborne mold (ratio of indoor to outdoor mold) and dust allergens in the homes of HEAL children were lower than measurements found in other studies, possibly because of extensive post-Katrina mold remediation and renovations, or because children moved into cleaner homes upon returning to New Orleans. PMID:22894816

Enzymatic treatment of whey proteins in cow's milk results in differential inhibition of IgE-mediated mast cell activation compared to T-cell activation.

PubMed

Knipping, Karen; van Esch, Betty C A M; van Ieperen-van Dijk, Adrie G; van Hoffen, Els; van Baalen, Ton; Knippels, Léon M J; van der Heide, Sicco; Dubois, Anthony E J; Garssen, Johan; Knol, Edward F

2012-01-01

Cow's milk (CM) hydrolysates are frequently used as milk substitutes for children with CM allergy. In hydrolysates, allergenic epitopes within CM proteins are diminished by enzymatic treatment. The aim of this study was to examine the allergenic and immunogenic properties of whey proteins during hydrolysis. During hydrolysis, samples were obtained at 0, 10, 15, 30, 45, 60, 75 and 90 min. Degradation was checked by HPLC and SDS-PAGE. Allergenic potential was analyzed by IgE crosslinking capacity of human Fcε receptor type 1-transduced rat basophilic leukemia cells sensitized with serum of CM-allergic patients. Whey-sensitized C3H/HeOuJ mice were ear challenged intracutaneously with the hydrolysates. Immunogenicity was tested using whey-specific human T-cell clones and T-cell lines at the level of proliferation and release of IL-4, IL-10, IL-13 and IFN-γ. After 15 min of hydrolysis, the majority of the proteins were degraded. Hydrolysis for 15 min resulted in 92% inhibition of mast cell degranulation and in 82% reduction of ear swelling in the mouse model. In contrast, T-cell-stimulatory capacity was less affected by hydrolysis: reduction of human T-cell proliferation was only 9%. This was further reduced to 57 and 74% after 30 and 45 min of hydrolysis, respectively. Cytokine production followed the pattern of T-cell proliferation. Via differential analysis of allergenic versus immunogenic properties of the time kinetics of hydrolysis of whey proteins, we have demonstrated specific hydrolysis conditions with reduced IgE-crosslinking responses but retained T-cell activating properties. This approach might be useful in better defining CM hydrolysates. Copyright © 2012 S. Karger AG, Basel.

Cur l 3, a major allergen of Curvularia lunata-derived short synthetic peptides, shows promise for successful immunotherapy.

PubMed

Sharma, Vidhu; Singh, Bhanu Pratap; Arora, Naveen

2011-12-01

Allergens with reduced IgE binding and intact T cell reactivity are required for safety and efficacy of immunotherapy (IT). Curvularia lunata is an important fungus for respiratory allergic disorders having cross-reactive and specific allergens. Previously, we have identified major allergens-namely, Cur l 1 (31 kD, serine protease), Cur l 2 (48 kD, enolase), and Cur l 3 (12 kD, cytochrome c)-from this fungus. Furthermore, Cur l 3 epitope-peptide, P6, showed immunogenicity and higher IgE binding, where cysteine and histidine were observed to be vital for IgE binding. Thus, this peptide and three derivatives with reduced IgE binding were selected for analysis in mice. In the present study, the effect of IT was assessed with Cur l 3, P6, its derivatives (P6.1-6.3), and P10 in a mouse model of allergy. IT with P6.2 and P10 reduced IgE and IgG1 levels significantly (P < 0.05), with increase in IgG2a levels as compared to other antigens. There was a significant reduction of IL-4 level associated with increased IFN-γ after IT. Airway inflammation was reduced significantly in terms of eosinophil counts in lung tissue and bronchoalveolar lavage fluid. IT with P6 and P6.2 induced significantly higher IL-10 secretion than baseline after 40 days of treatment. Generally, the effect of IT was more pronounced after 40 days than after 10 days of treatment. In summary, the modified peptide, P6.2, with reduced IgE binding, but intact immunogenicity, showed promise for successful IT.

Indoor environmental exposures for children with asthma enrolled in the HEAL study, post-Katrina New Orleans.

PubMed

Grimsley, L Faye; Chulada, Patricia C; Kennedy, Suzanne; White, LuAnn; Wildfire, Jeremy; Cohn, Richard D; Mitchell, Herman; Thornton, Eleanor; El-Dahr, Jane; Mvula, Mosanda M; Sterling, Yvonne; Martin, William J; Stephens, Kevin U; Lichtveld, Maureen

2012-11-01

Rain and flooding from Hurricane Katrina resulted in widespread growth of mold and bacteria and production of allergens in New Orleans, Louisiana, which may have led to increased exposures and morbidity in children with asthma. The goal of the Head-off Environmental Asthma in Louisiana (HEAL) study was to characterize post-Katrina exposures to mold and allergens in children with asthma. The homes of 182 children with asthma in New Orleans and surrounding parishes were evaluated by visual inspection, temperature and moisture measurements, and air and dust sampling. Air was collected using vacuum-pump spore traps and analyzed for > 30 mold taxa using bright field microscopy. Dust was collected from the children's beds and bedroom floors and analyzed for mouse (Mus m 1), dust mite (Der p 1), cockroach (Bla g 1), and mold (Alternaria mix) allergens using ELISA. More than half (62%) of the children were living in homes that had been damaged by rain, flooding, or both. Geometric mean indoor and outdoor airborne mold levels were 501 and 3,958 spores/m3, respectively. Alternaria antigen was detected in dust from 98% of homes, with 58% having concentrations > 10 µg/g. Mus m 1, Der p 1, and Bla g 1 were detected in 60%, 35%, and 20% of homes, respectively, at low mean concentrations. Except for Alternaria antigen in dust, concentrations of airborne mold (ratio of indoor to outdoor mold) and dust allergens in the homes of HEAL children were lower than measurements found in other studies, possibly because of extensive post-Katrina mold remediation and renovations, or because children moved into cleaner homes upon returning to New Orleans.

Strong and frequent T-cell responses to the minor allergen Phl p 12 in Spanish patients IgE-sensitized to Profilins.

PubMed

Lund, G; Brand, S; Ramos, T; Jimeno, L; Boissy, P; Vega, F; Arina, M; Christensen, L H; Hoof, I; Meno, K H; Barber, D; Blanco, C; Würtzen, P A; Andersen, P S

2018-05-01

Profilins are dominant pan-allergens known to cause cross-sensitization, leading to clinical symptoms such as pollen-food syndrome. This study aimed to determine the T-cell response to Phl p 12 in profilin-sensitized patients, by measuring the prevalence, strength and cross-reactivity to clinically relevant profilins. The release of Phl p allergens from pollen was determined by mass spectrometry and immunochemistry. T-cell responses, epitope mapping and cross-reactivity to profilins (Phl p 12, Ole e 2, Bet v 2 and Mal d 4) were measured in vitro using PBMCs from 26 Spanish grass-allergic donors IgE-sensitized to profilin. Cross-reactivity was addressed in vivo using 2 different mouse strains (BALB/c and C3H). Phl p 12 and Phl p 1 are released from pollen simultaneously and in similar amounts. Both T-cell response frequency (17/26 donors) and strength were comparable between Phl p 12 and Phl p 1. T-cell cross-reactivity to other profilins correlated with overall sequence homology, and 2 immunodominant epitope regions of Phl p 12 were identified. Data from mice immunized with Phl p 12 showed that cross-reactivity to Bet v 2 was mediated by conserved epitopes and further influenced by additional genetic factors, likely to be MHC II. The strength, prevalence and cross-reactivity of T-cell responses towards Phl p 12 are comparable to the major allergen Phl p 1, which supports the hypothesis that T cells to Phl p 12 can play an important role in development of allergic symptoms, such as those associated with pollen-food syndrome. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

What we miss if standard panel is used for skin prick testing?

PubMed

Cavkaytar, Ozlem; Buyuktiryaki, Betul; Sag, Erdal; Soyer, Ozge; Sekerel, Bulent E

2015-09-01

Although standard skin prick test (SPT) panels are crucial for routine investigation of sensitization in daily clinical practice, it has limitations in terms of missing allergens. To find out sensitization rates (SR)s to additional panel of allergens and their relative contributions in allergic diseases. SPTs with a battery of aeroallergens [tree pollen (A.glutinosa, C.arizonica, J.communis, T.platyphyllos, R.pseudoacacia), weed pollen (R.acetosa, U.dioica, A.artemisifolia), smut mix, yeast mix, storage mites (SM) (B.tropicalis, L.destructor, T.putrescentiae, A.siro), mouse and budgerigar epithelia], were performed to 318 participants (6-18 years) who were previously identified to be sensitized to at least one of the aeroallergens found in standard battery. Forty percent of participants were sensitized to at least one additional aerollergen. Three most frequent sensitizations were to B.tropicalis (11.3%), R.pseudoacacia (9.7%) and L.destructor (8.2%). SR for tree pollen increased from 6.9% to 19.8%, for mites increased from 26.3% to 31.6% and for moulds increased from 5.3% to 9.4% with addition of respective group of other allergens to battery. Furthermore, higher rates for additional tree pollen sensitization was found among patients with "only AR" (21%) compared to patients with "only asthma" (4.6%, p =0.006), contrarily higher rates for SM sensitization was found among patients with "only asthma" (20%) compared to patients with "only AR" (3.2%, p =0.003) CONCLUSIONS: Though some of sensitizations may occur due to cross-reactivity, almost 40% of sensitized children were also co-sensitized to the additional allergens tested. Physicians should consider further steps when a negative or inconsistent result is achieved through a standard skin test panel.

Effect of an Integrated Pest Management Intervention on Asthma Symptoms Among Mouse-Sensitized Children and Adolescents With Asthma: A Randomized Clinical Trial.

PubMed

Matsui, Elizabeth C; Perzanowski, Matthew; Peng, Roger D; Wise, Robert A; Balcer-Whaley, Susan; Newman, Michelle; Cunningham, Amparito; Divjan, Adnan; Bollinger, Mary E; Zhai, Shuyan; Chew, Ginger; Miller, Rachel L; Phipatanakul, Wanda

2017-03-14

Professionally delivered integrated pest management (IPM) interventions can reduce home mouse allergen concentrations, but whether they reduce asthma morbidity among mouse-sensitized and exposed children and adolescents is unknown. To determine the effect of an IPM intervention on asthma morbidity among mouse-sensitized and exposed children and adolescents with asthma. Randomized clinical trial conducted in Baltimore, Maryland, and Boston, Massachusetts. Participants were mouse-sensitized and exposed children and adolescents (aged 5-17 years) with asthma randomized to receive professionally delivered IPM plus pest management education or pest management education alone. Enrollment occurred between May 2010 and August 2014; the final follow-up visit occurred on September 25, 2015. Integrated pest management consisted of application of rodenticide, sealing of holes that could serve as entry points for mice, trap placement, targeted cleaning, allergen-proof mattress and pillow encasements, and portable air purifiers. Infestation was assessed every 3 months, and if infestation persisted or recurred, additional treatments were delivered. All participants received pest management education, which consisted of written material and demonstration of the materials needed to set traps and seal holes. The primary outcome was maximal symptom days defined as the highest number of days of symptoms in the previous 2 weeks among 3 types of symptoms (days of slowed activity due to asthma; number of nights of waking with asthma symptoms; and days of coughing, wheezing, or chest tightness) across 6, 9, and 12 months. Of 361 children and adolescents who were randomized (mean [SD] age, 9.8 [3.2] years; 38% female; 181 in IPM plus pest management education group and 180 in pest management education alone group), 334 were included in the primary analysis. For the primary outcome, there was no statistically significant between-group difference for maximal symptom days across 6, 9, and 12 months with a median of 2.0 (interquartile range, 0.7-4.7) maximal symptom days in the IPM plus pest management education group and 2.7 (interquartile range, 1.3-5.0) maximal symptom days in the pest management education alone group (P = .16) and a ratio of symptom frequencies of 0.86 (95% CI, 0.69-1.06). Among mouse-sensitized and exposed children and adolescents with asthma, an intensive year-long integrated pest management intervention plus pest management education vs pest management education alone resulted in no significant difference in maximal symptom days from 6 to 12 months. clinicaltrials.gov Identifier: NCT01251224.

Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma.

PubMed

Patel, Kruti R; Bai, Yan; Trieu, Kenneth G; Barrios, Juliana; Ai, Xingbin

2017-10-01

Asthma often progresses into adulthood from early-life episodes of adverse environmental exposures. However, how the injury to developing lungs contributes to the pathophysiology of persistent asthma remains poorly understood. In this study, we identified an age-related mechanism along the cholinergic nerve-airway smooth muscle (ASM) axis that underlies prolonged airway hyperreactivity (AHR) in mice. We showed that ASM continued to mature until ∼3 wk after birth. Coinciding with postnatal ASM maturation, there was a critical time window for the development of ASM hypercontractility after cholinergic stimulation. We found that allergen exposure in neonatal mice, but not in adult mice, elevated the level and activity of cholinergic nerves (termed neuroplasticity). We demonstrated that cholinergic neuroplasticity is necessary for the induction of persistent AHR after neonatal exposure during rescue assays in mice deficient in neuroplasticity. In addition, early intervention with cholinergic receptor muscarinic (ChRM)-3 blocker reversed the progression of AHR in the neonatal exposure model, whereas β2-adrenoceptor agonists had no such effect. Together, our findings demonstrate a functional relationship between cholinergic neuroplasticity and ASM contractile phenotypes that operates uniquely in early life to induce persistent AHR after allergen exposure. Targeting ChRM3 may have disease-modifying benefits in childhood asthma.-Patel, K. R., Bai, Y., Trieu, K. G., Barrios, J., Ai, X. Targeting acetylcholine receptor M3 prevents the progression of airway hyperreactivity in a mouse model of childhood asthma. © FASEB.

A Jagged 1-Notch 4 molecular switch mediates airway inflammation induced by ultrafine particles.

PubMed

Xia, Mingcan; Harb, Hani; Saffari, Arian; Sioutas, Constantinos; Chatila, Talal A

2018-04-05

Exposure to traffic-related particulate matter promotes asthma and allergic diseases. However, the precise cellular and molecular mechanisms by which particulate matter exposure acts to mediate these effects remain unclear. We sought to elucidate the cellular targets and signaling pathways critical for augmentation of allergic airway inflammation induced by ambient ultrafine particles (UFP). We used in vitro cell-culture assays with lung-derived antigen-presenting cells and allergen-specific T cells and in vivo mouse models of allergic airway inflammation with myeloid lineage-specific gene deletions, cellular reconstitution approaches, and antibody inhibition studies. We identified lung alveolar macrophages (AM) as the key cellular target of UFP in promoting airway inflammation. Aryl hydrocarbon receptor-dependent induction of Jagged 1 (Jag1) expression in AM was necessary and sufficient for augmentation of allergic airway inflammation by UFP. UFP promoted T H 2 and T H 17 cell differentiation of allergen-specific T cells in a Jag1- and Notch 4-dependent manner. Treatment of mice with an anti-Notch 4 antibody abrogated exacerbation of allergic airway inflammation induced by UFP. UFP exacerbate allergic airway inflammation by promoting a Jag1-Notch 4-dependent interaction between AM and allergen-specific T cells, leading to augmented T H cell differentiation. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Efficient induction of CD25- iTreg by co-immunization requires strongly antigenic epitopes for T cells.

PubMed

Geng, Shuang; Yu, Yang; Kang, Youmin; Pavlakis, George; Jin, Huali; Li, Jinyao; Hu, Yanxin; Hu, Weibin; Wang, Shuang; Wang, Bin

2011-05-05

We previously showed that co-immunization with a protein antigen and a DNA vaccine coding for the same antigen induces CD40 low IL-10 high tolerogenic DCs, which in turn stimulates the expansion of antigen-specific CD4+CD25-Foxp3+ regulatory T cells (CD25- iTreg). However, it was unclear how to choose the antigen sequence to maximize tolerogenic antigen presentation and, consequently, CD25- iTreg induction. In the present study, we demonstrated the requirement of highly antigenic epitopes for CD25- iTreg induction. Firstly, we showed that the induction of CD25- iTreg by tolerogenic DC can be blocked by anti-MHC-II antibody. Next, both the number and the suppressive activity of CD25- iTreg correlated positively with the overt antigenicity of an epitope to activate T cells. Finally, in a mouse model of dermatitis, highly antigenic epitopes derived from a flea allergen not only induced more CD25- iTreg, but also more effectively prevented allergenic reaction to the allergen than did weakly antigenic epitopes. Our data thus indicate that efficient induction of CD25- iTreg requires highly antigenic peptide epitopes. This finding suggests that highly antigenic epitopes should be used for efficient induction of CD25- iTreg for clinical applications such as flea allergic dermatitis.

Allergen-induced dermatitis causes alterations in cutaneous retinoid-mediated signaling in mice.

PubMed

Gericke, Janine; Ittensohn, Jan; Mihály, Johanna; Dubrac, Sandrine; Rühl, Ralph

2013-01-01

Nuclear receptor-mediated signaling via RARs and PPARδ is involved in the regulation of skin homeostasis. Moreover, activation of both RAR and PPARδ was shown to alter skin inflammation. Endogenous all-trans retinoic acid (ATRA) can activate both receptors depending on specific transport proteins: Fabp5 initiates PPARδ signaling whereas Crabp2 promotes RAR signaling. Repetitive topical applications of ovalbumin (OVA) in combination with intraperitoneal injections of OVA or only intraperitoneal OVA applications were used to induce allergic dermatitis. In our mouse model, expression of IL-4, and Hbegf increased whereas expression of involucrin, Abca12 and Spink5 decreased in inflamed skin, demonstrating altered immune response and epidermal barrier homeostasis. Comprehensive gene expression analysis showed alterations of the cutaneous retinoid metabolism and retinoid-mediated signaling in allergic skin immune response. Notably, ATRA synthesis was increased as indicated by the elevated expression of retinaldehyde dehydrogenases and increased levels of ATRA. Consequently, the expression pattern of genes downstream to RAR was altered. Furthermore, the increased ratio of Fabp5 vs. Crabp2 may indicate an up-regulation of the PPARδ pathway in allergen-induced dermatitis in addition to the altered RAR signaling. Thus, our findings suggest that ATRA levels, RAR-mediated signaling and signaling involved in PPARδ pathways are mainly increased in allergen-induced dermatitis and may contribute to the development and/or maintenance of allergic skin diseases.

Synergistic effects of dendritic cell targeting and laser-microporation on enhancing epicutaneous skin vaccination efficacy.

PubMed

Machado, Yoan; Duinkerken, Sanne; Hoepflinger, Veronika; Mayr, Melissa; Korotchenko, Evgeniia; Kurtaj, Almedina; Pablos, Isabel; Steiner, Markus; Stoecklinger, Angelika; Lübbers, Joyce; Schmid, Maximillian; Ritter, Uwe; Scheiblhofer, Sandra; Ablinger, Michael; Wally, Verena; Hochmann, Sarah; Raninger, Anna M; Strunk, Dirk; van Kooyk, Yvette; Thalhamer, Josef; Weiss, Richard

2017-11-28

Due to its unique immunological properties, the skin is an attractive target tissue for allergen-specific immunotherapy. In our current work, we combined a dendritic cell targeting approach with epicutaneous immunization using an ablative fractional laser to generate defined micropores in the upper layers of the skin. By coupling the major birch pollen allergen Bet v 1 to mannan from S. cerevisiae via mild periodate oxidation we generated hypoallergenic Bet-mannan neoglycoconjugates, which efficiently targeted CD14 + dendritic cells and Langerhans cells in human skin explants. Mannan conjugation resulted in sustained release from the skin and retention in secondary lymphoid organs, whereas unconjugated antigen showed fast renal clearance. In a mouse model, Bet-mannan neoglycoconjugates applied via laser-microporated skin synergistically elicited potent humoral and cellular immune responses, superior to intradermal injection. The induced antibody responses displayed IgE-blocking capacity, highlighting the therapeutic potential of the approach. Moreover, application via micropores, but not by intradermal injection, resulted in a mixed TH1/TH17-biased immune response. Our data clearly show that applying mannan-neoglycoconjugates to an organ rich in dendritic cells using laser-microporation is superior to intradermal injection. Due to their low IgE binding capacity and biodegradability, mannan neoglycoconjugates therefore represent an attractive formulation for allergen-specific epicutaneous immunotherapy. Copyright © 2017 Elsevier B.V. All rights reserved.

Allergen-Induced Dermatitis Causes Alterations in Cutaneous Retinoid-Mediated Signaling in Mice

PubMed Central

Gericke, Janine; Ittensohn, Jan; Mihály, Johanna; Dubrac, Sandrine; Rühl, Ralph

2013-01-01

Nuclear receptor-mediated signaling via RARs and PPARδ is involved in the regulation of skin homeostasis. Moreover, activation of both RAR and PPARδ was shown to alter skin inflammation. Endogenous all-trans retinoic acid (ATRA) can activate both receptors depending on specific transport proteins: Fabp5 initiates PPARδ signaling whereas Crabp2 promotes RAR signaling. Repetitive topical applications of ovalbumin (OVA) in combination with intraperitoneal injections of OVA or only intraperitoneal OVA applications were used to induce allergic dermatitis. In our mouse model, expression of IL-4, and Hbegf increased whereas expression of involucrin, Abca12 and Spink5 decreased in inflamed skin, demonstrating altered immune response and epidermal barrier homeostasis. Comprehensive gene expression analysis showed alterations of the cutaneous retinoid metabolism and retinoid-mediated signaling in allergic skin immune response. Notably, ATRA synthesis was increased as indicated by the elevated expression of retinaldehyde dehydrogenases and increased levels of ATRA. Consequently, the expression pattern of genes downstream to RAR was altered. Furthermore, the increased ratio of Fabp5 vs. Crabp2 may indicate an up-regulation of the PPARδ pathway in allergen-induced dermatitis in addition to the altered RAR signaling. Thus, our findings suggest that ATRA levels, RAR-mediated signaling and signaling involved in PPARδ pathways are mainly increased in allergen-induced dermatitis and may contribute to the development and/or maintenance of allergic skin diseases. PMID:23977003

A distinct microbiota composition is associated with protection from food allergy in an oral mouse immunization model.

PubMed

Diesner, Susanne C; Bergmayr, Cornelia; Pfitzner, Barbara; Assmann, Vera; Krishnamurthy, Durga; Starkl, Philipp; Endesfelder, David; Rothballer, Michael; Welzl, Gerhard; Rattei, Thomas; Eiwegger, Thomas; Szépfalusi, Zsolt; Fehrenbach, Heinz; Jensen-Jarolim, Erika; Hartmann, Anton; Pali-Schöll, Isabella; Untersmayr, Eva

2016-12-01

In our mouse model, gastric acid-suppression is associated with antigen-specific IgE and anaphylaxis development. We repeatedly observed non-responder animals protected from food allergy. Here, we aimed to analyse reasons for this protection. Ten out of 64 mice, subjected to oral ovalbumin (OVA) immunizations under gastric acid-suppression, were non-responders without OVA-specific IgE or IgG1 elevation, indicating protection from allergy. In these non-responders, allergen challenges confirmed reduced antigen uptake and lack of anaphylactic symptoms, while in allergic mice high levels of mouse mast-cell protease-1 and a body temperature reduction, indicative for anaphylaxis, were determined. Upon OVA stimulation, significantly lower IL-4, IL-5, IL-10 and IL-13 levels were detected in non-responders, while IL-22 was significantly higher. Comparison of fecal microbiota revealed differences of bacterial communities on single bacterial Operational-Taxonomic-Unit level between the groups, indicating protection from food allergy being associated with a distinct microbiota composition in a non-responding phenotype in this mouse model. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Obese asthmatic patients have decreased surfactant protein A levels: Mechanisms and implications.

PubMed

Lugogo, Njira; Francisco, Dave; Addison, Kenneth J; Manne, Akarsh; Pederson, William; Ingram, Jennifer L; Green, Cynthia L; Suratt, Benjamin T; Lee, James J; Sunday, Mary E; Kraft, Monica; Ledford, Julie G

2018-03-01

Eosinophils are prominent in some patients with asthma and are increased in the submucosa in a subgroup of obese patients with asthma (OAs). Surfactant protein A (SP-A) modulates host responses to infectious and environmental insults. We sought to determine whether SP-A levels are altered in OAs compared with a control group and to determine the implications of these alterations in SP-A levels in asthmatic patients. Bronchoalveolar lavage fluid from 23 lean, 12 overweight, and 20 obese subjects were examined for SP-A. Mouse tracheal epithelial cells grown at an air-liquid interface were used for mechanistic studies. SP-A -/- mice were challenged in allergen models, and exogenous SP-A therapy was given after the last challenge. Eosinophils were visualized and quantitated in lung parenchyma by means of immunostaining. Significantly less SP-A (P = .002) was detected in samples from OAs compared with those from control subjects. A univariable regression model found SP-A levels were significantly negatively correlated with body mass index (r = -0.33, P = .014), whereas multivariable modeling demonstrated that the correlation depended both on asthma status (P = .017) and the interaction of asthma and body mass index (P = .008). Addition of exogenous TNF-α to mouse tracheal epithelial cells was sufficient to attenuate SP-A and eotaxin secretion. Allergen-challenged SP-A -/- mice that received SP-A therapy had significantly less tissue eosinophilia compared with mice receiving vehicle. SP-A functions as an important mediator in resolving tissue and lavage fluid eosinophilia in allergic mouse models. Decreased levels of SP-A in OAs, which could be due to increased local TNF-α levels, might lead to impaired eosinophil resolution and could contribute to the eosinophilic asthma phenotype. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

IL-23 secreted by bronchial epithelial cells contributes to allergic sensitization in asthma model: role of IL-23 secreted by bronchial epithelial cells.

PubMed

Lee, Hyun Seung; Park, Da-Eun; Lee, Ji-Won; Chang, Yuna; Kim, Hye Young; Song, Woo-Jung; Kang, Hye-Ryun; Park, Heung-Woo; Chang, Yoon-Seok; Cho, Sang-Heon

2017-01-01

IL-23 has been postulated to be a critical mediator contributing to various inflammatory diseases. Dermatophagoides pteronyssinus (Der p) is one of the most common inhalant allergens. However, the role of IL-23 in Der p-induced mouse asthma model is not well understood, particularly with regard to the development of allergic sensitization in the airways. The objective of this study was to evaluate roles of IL-23 in Der p sensitization and asthma development. BALB/c mice were repeatedly administered Der p intranasally to develop Der p allergic sensitization and asthma. After Der p local administration, changes in IL-23 expression were examined in lung tissues and primary epithelial cells. Anti-IL-23p19 antibody was given during the Der p sensitization period, and its effects were examined. Effects of anti-IL-23p19 antibody at bronchial epithelial levels were also examined in vitro. The expression of IL-23 at bronchial epithelial layers was increased after Der p local administration in mouse. In Der p-induced mouse models, anti-IL-23p19 antibody treatment during allergen sensitization significantly diminished Der p allergic sensitization and several features of allergic asthma including the production of Th2 cytokines and the population of type 2 innate lymphoid cells in lungs. The activation of dendritic cells in lung-draining lymph nodes was also reduced by anti-IL-23 treatment. In murine lung alveolar type II-like epithelial cell line (MLE-12) cells, IL-23 blockade prevented cytokine responses to Der p stimulation, such as IL-1α, granulocyte-macrophage colony-stimulating factor (GM-CSF), IL-33, and also bone marrow-derived dendritic cell activation. In conclusion, IL-23 is another important bronchial epithelial cell-driven cytokine which may contribute to the development of house dust mite allergic sensitization and asthma. Copyright © 2017 the American Physiological Society.

Perinatal maternal administration of Lactobacillus paracasei NCC 2461 prevents allergic inflammation in a mouse model of birch pollen allergy.

PubMed

Schabussova, Irma; Hufnagl, Karin; Tang, Mimi L K; Hoflehner, Elisabeth; Wagner, Angelika; Loupal, Gerhard; Nutten, Sophie; Zuercher, Adrian; Mercenier, Annick; Wiedermann, Ursula

2012-01-01

The hygiene hypothesis implies that microbial agents including probiotic bacteria may modulate foetal/neonatal immune programming and hence offer effective strategies for primary allergy prevention; however their mechanisms of action are poorly understood. We investigated whether oral administration of Lactobacillus paracasei NCC 2461 to mothers during gestation/lactation can protect against airway inflammation in offspring in a mouse model of birch pollen allergy, and examined the immune mechanisms involved. BALB/c mice were treated daily with L. paracasei in drinking water or drinking water alone in the last week of gestation and during lactation. Their offspring were sensitized with recombinant Bet v 1, followed by aerosol challenge with birch pollen extract. Maternal exposure to L. paracasei prevented the development of airway inflammation in offspring, as demonstrated by attenuation of eosinophil influx in the lungs; reduction of IL-5 levels in bronchoalveolar lavage, and in lung and mediastinal lymph node cell cultures; and reduced peribronchial inflammatory infiltrate and mucus hypersecretion. While allergen-specific IgE and IgG antibody levels remained unchanged by the treatment, IL-4 and IL-5 production in spleen cell cultures were significantly reduced upon allergen stimulation in offspring of L. paracasei treated mice. Offspring of L. paracasei supplemented mothers had significantly reduced Bet v 1-specific as well as Concanavalin A-induced responses in spleen and mesenteric lymph node cell cultures, suggesting the modulation of both antigen-specific and mitogen-induced immune responses in offspring. These effects were associated with increased Foxp3 mRNA expression in the lungs and increased TGF-beta in serum. Our data show that in a mouse model of birch pollen allergy, perinatal administration of L. paracasei NCC 2461 to pregnant/lactating mothers protects against the development of airway inflammation in offspring by activating regulatory pathways, likely through TLR2/4 signalling.

Perinatal Maternal Administration of Lactobacillus paracasei NCC 2461 Prevents Allergic Inflammation in a Mouse Model of Birch Pollen Allergy

PubMed Central

Schabussova, Irma; Hufnagl, Karin; Tang, Mimi L. K.; Hoflehner, Elisabeth; Wagner, Angelika; Loupal, Gerhard; Nutten, Sophie; Zuercher, Adrian; Mercenier, Annick; Wiedermann, Ursula

2012-01-01

Background The hygiene hypothesis implies that microbial agents including probiotic bacteria may modulate foetal/neonatal immune programming and hence offer effective strategies for primary allergy prevention; however their mechanisms of action are poorly understood. We investigated whether oral administration of Lactobacillus paracasei NCC 2461 to mothers during gestation/lactation can protect against airway inflammation in offspring in a mouse model of birch pollen allergy, and examined the immune mechanisms involved. Methods BALB/c mice were treated daily with L. paracasei in drinking water or drinking water alone in the last week of gestation and during lactation. Their offspring were sensitized with recombinant Bet v 1, followed by aerosol challenge with birch pollen extract. Results Maternal exposure to L. paracasei prevented the development of airway inflammation in offspring, as demonstrated by attenuation of eosinophil influx in the lungs; reduction of IL-5 levels in bronchoalveolar lavage, and in lung and mediastinal lymph node cell cultures; and reduced peribronchial inflammatory infiltrate and mucus hypersecretion. While allergen-specific IgE and IgG antibody levels remained unchanged by the treatment, IL-4 and IL-5 production in spleen cell cultures were significantly reduced upon allergen stimulation in offspring of L. paracasei treated mice. Offspring of L. paracasei supplemented mothers had significantly reduced Bet v 1-specific as well as Concanavalin A-induced responses in spleen and mesenteric lymph node cell cultures, suggesting the modulation of both antigen-specific and mitogen-induced immune responses in offspring. These effects were associated with increased Foxp3 mRNA expression in the lungs and increased TGF-beta in serum. Conclusion Our data show that in a mouse model of birch pollen allergy, perinatal administration of L. paracasei NCC 2461 to pregnant/lactating mothers protects against the development of airway inflammation in offspring by activating regulatory pathways, likely through TLR2/4 signalling. PMID:22792257

Another cat and mouse game: Deciphering the evolution of the SCGB superfamily and exploring the molecular similarity of major cat allergen Fel d 1 and mouse ABP using computational approaches

PubMed Central

Pageat, Patrick; Bienboire-Frosini, Cécile

2018-01-01

The mammalian secretoglobin (SCGB) superfamily contains functionally diverse members, among which the major cat allergen Fel d 1 and mouse salivary androgen-binding protein (ABP) display similar subunits. We searched for molecular similarities between Fel d 1 and ABP to examine the possibility that they play similar roles. We aimed to i) cluster the evolutionary relationships of the SCGB superfamily; ii) identify divergence patterns, structural overlap, and protein-protein docking between Fel d 1 and ABP dimers; and iii) explore the residual interaction between ABP dimers and steroid binding in chemical communication using computational approaches. We also report that the evolutionary tree of the SCGB superfamily comprises seven unique palm-like clusters, showing the evolutionary pattern and divergence time tree of Fel d 1 with 28 ABP paralogs. Three ABP subunits (A27, BG27, and BG26) share phylogenetic relationships with Fel d 1 chains. The Fel d 1 and ABP subunits show similarities in terms of sequence conservation, identical motifs and binding site clefts. Topologically equivalent positions were visualized through superimposition of ABP A27:BG27 (AB) and ABP A27:BG26 (AG) dimers on a heterodimeric Fel d 1 model. In docking, Fel d 1-ABP dimers exhibit the maximum surface binding ability of AG compared with that of AB dimers and the several polar interactions between ABP dimers with steroids. Hence, cat Fel d 1 is an ABP-like molecule in which monomeric chains 1 and 2 are the equivalent of the ABPA and ABPBG monomers, respectively. These findings suggest that the biological and molecular function of Fel d 1 is similar to that of ABP in chemical communication, possibly via pheromone and/or steroid binding. PMID:29771985

Another cat and mouse game: Deciphering the evolution of the SCGB superfamily and exploring the molecular similarity of major cat allergen Fel d 1 and mouse ABP using computational approaches.

PubMed

Durairaj, Rajesh; Pageat, Patrick; Bienboire-Frosini, Cécile

2018-01-01

The mammalian secretoglobin (SCGB) superfamily contains functionally diverse members, among which the major cat allergen Fel d 1 and mouse salivary androgen-binding protein (ABP) display similar subunits. We searched for molecular similarities between Fel d 1 and ABP to examine the possibility that they play similar roles. We aimed to i) cluster the evolutionary relationships of the SCGB superfamily; ii) identify divergence patterns, structural overlap, and protein-protein docking between Fel d 1 and ABP dimers; and iii) explore the residual interaction between ABP dimers and steroid binding in chemical communication using computational approaches. We also report that the evolutionary tree of the SCGB superfamily comprises seven unique palm-like clusters, showing the evolutionary pattern and divergence time tree of Fel d 1 with 28 ABP paralogs. Three ABP subunits (A27, BG27, and BG26) share phylogenetic relationships with Fel d 1 chains. The Fel d 1 and ABP subunits show similarities in terms of sequence conservation, identical motifs and binding site clefts. Topologically equivalent positions were visualized through superimposition of ABP A27:BG27 (AB) and ABP A27:BG26 (AG) dimers on a heterodimeric Fel d 1 model. In docking, Fel d 1-ABP dimers exhibit the maximum surface binding ability of AG compared with that of AB dimers and the several polar interactions between ABP dimers with steroids. Hence, cat Fel d 1 is an ABP-like molecule in which monomeric chains 1 and 2 are the equivalent of the ABPA and ABPBG monomers, respectively. These findings suggest that the biological and molecular function of Fel d 1 is similar to that of ABP in chemical communication, possibly via pheromone and/or steroid binding.

Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions.

PubMed

Turner, Leslie M; Harr, Bettina

2014-12-09

Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculus musculus and M. m. domesticus. Many generations of admixture enables high-resolution mapping of loci contributing to these sterility-related phenotypes. We identify complex interactions among sterility loci, suggesting multiple, non-independent genetic incompatibilities contribute to barriers to gene flow in the hybrid zone.

Allergic asthma induced in rhesus monkeys by house dust mite (Dermatophagoides farinae).

PubMed

Schelegle, E S; Gershwin, L J; Miller, L A; Fanucchi, M V; Van Winkle, L S; Gerriets, J P; Walby, W F; Omlor, A M; Buckpitt, A R; Tarkington, B K; Wong, V J; Joad, J P; Pinkerton, K B; Wu, R; Evans, M J; Hyde, D M; Plopper, C G

2001-01-01

To establish whether allergic asthma could be induced experimentally in a nonhuman primate using a common human allergen, three female rhesus monkeys (Macaca mulatta) were sensitized with house dust mite (Dermatophagoides farinae) allergen (HDMA) by subcutaneous injection, followed by four intranasal sensitizations, and exposure to allergen aerosol 3 hours per day, 3 days per week for up to 13 weeks. Before aerosol challenge, all three monkeys skin-tested positive for HDMA. During aerosol challenge with HDMA, sensitized monkeys exhibited cough and rapid shallow breathing and increased airway resistance, which was reversed by albuterol aerosol treatment. Compared to nonsensitized monkeys, there was a fourfold reduction in the dose of histamine aerosol necessary to produce a 150% increase in airway resistance in sensitized monkeys. After aerosol challenge, serum levels of histamine were elevated in sensitized monkeys. Sensitized monkeys exhibited increased levels of HDMA-specific IgE in serum, numbers of eosinophils and exfoliated cells within lavage, and elevated CD25 expression on circulating CD4(+) lymphocytes. Intrapulmonary bronchi of sensitized monkeys had focal mucus cell hyperplasia, interstitial infiltrates of eosinophils, and thickening of the basement membrane zone. We conclude that a model of allergic asthma can be induced in rhesus monkeys using a protocol consisting of subcutaneous injection, intranasal instillation, and aerosol challenge with HDMA.

Allergic Asthma Induced in Rhesus Monkeys by House Dust Mite (Dermatophagoides farinae)

PubMed Central

Schelegle, Edward S.; Gershwin, Laurel J.; Miller, Lisa A.; Fanucchi, Michelle V.; Van Winkle, Laura S.; Gerriets, Joan P.; Walby, William F.; Omlor, Amanda M.; Buckpitt, Alan R.; Tarkington, Brian K.; Wong, Viviana J.; Joad, Jesse P.; Pinkerton, Kent B.; Wu, Reen; Evans, Michael J.; Hyde, Dallas M.; Plopper, Charles G.

2001-01-01

To establish whether allergic asthma could be induced experimentally in a nonhuman primate using a common human allergen, three female rhesus monkeys (Macaca mulatta) were sensitized with house dust mite (Dermatophagoides farinae) allergen (HDMA) by subcutaneous injection, followed by four intranasal sensitizations, and exposure to allergen aerosol 3 hours per day, 3 days per week for up to 13 weeks. Before aerosol challenge, all three monkeys skin-tested positive for HDMA. During aerosol challenge with HDMA, sensitized monkeys exhibited cough and rapid shallow breathing and increased airway resistance, which was reversed by albuterol aerosol treatment. Compared to nonsensitized monkeys, there was a fourfold reduction in the dose of histamine aerosol necessary to produce a 150% increase in airway resistance in sensitized monkeys. After aerosol challenge, serum levels of histamine were elevated in sensitized monkeys. Sensitized monkeys exhibited increased levels of HDMA-specific IgE in serum, numbers of eosinophils and exfoliated cells within lavage, and elevated CD25 expression on circulating CD4+ lymphocytes. Intrapulmonary bronchi of sensitized monkeys had focal mucus cell hyperplasia, interstitial infiltrates of eosinophils, and thickening of the basement membrane zone. We conclude that a model of allergic asthma can be induced in rhesus monkeys using a protocol consisting of subcutaneous injection, intranasal instillation, and aerosol challenge with HDMA. PMID:11141508

Weight Loss Decreases Inherent and Allergic Methacholine Hyperresponsiveness in Mouse Models of Diet-Induced Obese Asthma

PubMed Central

Ather, Jennifer L.; Chung, Michael; Hoyt, Laura R.; Randall, Matthew J.; Georgsdottir, Anna; Daphtary, Nirav A.; Aliyeva, Minara I.; Suratt, Benjamin T.; Bates, Jason H. T.; Irvin, Charles G.; Russell, Sheila R.; Forgione, Patrick M.; Dixon, Anne E.

2016-01-01

Obese asthma presents with inherent hyperresponsiveness to methacholine or augmented allergen-driven allergic asthma, with an even greater magnitude of methacholine hyperresponsiveness. These physiologic parameters and accompanying obese asthma symptoms can be reduced by successful weight loss, yet the underlying mechanisms remain incompletely understood. We implemented mouse models of diet-induced obesity, dietary and surgical weight loss, and environmental allergen exposure to examine the mechanisms and mediators of inherent and allergic obese asthma. We report that the methacholine hyperresponsiveness in these models of inherent obese asthma and obese allergic asthma manifests in distinct anatomical compartments but that both are amenable to interventions that induce substantial weight loss. The inherent obese asthma phenotype, with characteristic increases in distal airspace tissue resistance and tissue elastance, is associated with elevated proinflammatory cytokines that are reduced with dietary weight loss. Surprisingly, bariatric surgery–induced weight loss further elevates these cytokines while reducing methacholine responsiveness to levels similar to those in lean mice or in formerly obese mice rendered lean through dietary intervention. In contrast, the obese allergic asthma phenotype, with characteristic increases in central airway resistance, is not associated with increased adaptive immune responses, yet diet-induced weight loss reduces methacholine hyperresponsiveness without altering immunological variables. Diet-induced weight loss is effective in models of both inherent and allergic obese asthma, and our examination of the fecal microbiome revealed that the obesogenic Firmicutes/Bacteroidetes ratio was normalized after diet-induced weight loss. Our results suggest that structural, immunological, and microbiological factors contribute to the manifold presentations of obese asthma. PMID:27064658

Down-regulation of Glutathione S-transferase Pi in Asthma Contributes to Enhanced Oxidative Stress

PubMed Central

Schroer, Kathy T.; Gibson, Aaron M.; Sivaprasad, Umasundari; Bass, Stacey A.; Ericksen, Mark B.; Wills-Karp, Marsha; LeCras, Tim; Fitzpatrick, Anne M.; Brown, Lou Ann S.; Stringer, Keith F.; Khurana Hershey, Gurjit K.

2011-01-01

Background Glutathione S-transferase Pi (GSTPi) is the predominant redox regulator in the lung. While evidence implicates an important role for GSTPi in asthma, the mechanism for this has remained elusive. Objectives To determine how GSTPi is regulated in asthma and to elucidate its role in maintaining redox homeostasis. Methods We elucidated the regulation of GSTPi in children with asthma and utilized murine models of asthma to determine the role of GSTPi in redox homeostasis. Measurements and Main Results Our findings demonstrate that GSTPi transcript levels are markedly down-regulated in allergen and IL-13 treated mouse models of asthma via STAT6 dependent and independent pathways. Nuclear factor-erythroid 2 related factor 2 (Nrf2) was also down-regulated in these models. The decrease in GSTPi expression was associated with decreased total GST activity in the lungs of mice. Examination of cystine intermediates uncovered a functional role for GSTPi in regulating Cys oxidation, whereby GSTPi-deficient mice exhibited increased oxidative stress (increase in % cystine) compared with wild-type mice following allergen challenge. GSTPi expression was similarly down-regulated in children with asthma. Conclusions These data collectively suggest that down-regulation of GSTPi following allergen challenge may contribute to the asthma phenotype due to disruption of redox homeostasis and increased oxidative stress. Furthermore, GSTPi may be an important therapeutic target for asthma, and evaluation of GSTPi expression may prove beneficial in identifying individuals who would benefit from therapy targeting this pathway. PMID:21570714

Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions

PubMed Central

Turner, Leslie M; Harr, Bettina

2014-01-01

Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculus musculus and M. m. domesticus. Many generations of admixture enables high-resolution mapping of loci contributing to these sterility-related phenotypes. We identify complex interactions among sterility loci, suggesting multiple, non-independent genetic incompatibilities contribute to barriers to gene flow in the hybrid zone. DOI: http://dx.doi.org/10.7554/eLife.02504.001 PMID:25487987

Calcium-sensing receptor antagonists abrogate airway hyperresponsiveness and inflammation in allergic asthma

PubMed Central

Yarova, Polina L.; Stewart, Alecia L.; Sathish, Venkatachalem; Britt, Rodney D; Thompson, Michael A.; Lowe, Alexander P. P.; Freeman, Michelle; Aravamudan, Bharathi; Kita, Hirohito; Brennan, Sarah C.; Schepelmann, Martin; Davies, Thomas; Yung, Sun; Cholisoh, Zakky; Kidd, Emma J.; Ford, William R.; Broadley, Kenneth J.; Rietdorf, Katja; Chang, Wenhan; Khayat, Mohd E. Bin; Ward, Donald T.; Corrigan, Christopher J.; Ward, Jeremy P. T.; Kemp, Paul J.; Pabelick, Christina M.; Prakash, Y. S.; Riccardi, Daniela

2016-01-01

Airway hyperresponsiveness and inflammation are fundamental hallmarks of allergic asthma that are accompanied by increases in certain polycations, such as eosinophil cationic protein. Levels of these cations in body fluids correlate with asthma severity. We show that polycations and elevated extracellular calcium activate the human recombinant and native calcium-sensing receptor (CaSR), leading to intracellular calcium mobilization, cyclic adenosine monophosphate breakdown, and p38 mitogen-activated protein kinase phosphorylation in airway smooth muscle (ASM) cells. These effects can be prevented by CaSR antagonists, termed calcilytics. Moreover, asthmatic patients and allergen-sensitized mice expressed more CaSR in ASMs than did their healthy counterparts. Indeed, polycations induced hyper-reactivity in mouse bronchi, and this effect was prevented by calcilytics and absent in mice with CaSR ablation from ASM. Calcilytics also reduced airway hyperresponsiveness and inflammation in allergen-sensitized mice in vivo. These data show that a functional CaSR is up-regulated in asthmatic ASM and targeted by locally produced polycations to induce hyperresponsiveness and inflammation. Thus, calcilytics may represent effective asthma therapeutics. PMID:25904744

SPDEF regulates goblet cell hyperplasia in the airway epithelium

PubMed Central

Park, Kwon-Sik; Korfhagen, Thomas R.; Bruno, Michael D.; Kitzmiller, Joseph A.; Wan, Huajing; Wert, Susan E.; Khurana Hershey, Gurjit K.; Chen, Gang; Whitsett, Jeffrey A.

2007-01-01

Goblet cell hyperplasia and mucous hypersecretion contribute to the pathogenesis of chronic pulmonary diseases including cystic fibrosis, asthma, and chronic obstructive pulmonary disease. In the present work, mouse SAM pointed domain-containing ETS transcription factor (SPDEF) mRNA and protein were detected in subsets of epithelial cells lining the trachea, bronchi, and tracheal glands. SPDEF interacted with the C-terminal domain of thyroid transcription factor 1, activating transcription of genes expressed selectively in airway epithelial cells, including Sftpa, Scgb1a1, Foxj1, and Sox17. Expression of Spdef in the respiratory epithelium of adult transgenic mice caused goblet cell hyperplasia, inducing both acidic and neutral mucins in vivo, and stainined for both acidic and neutral mucins in vivo. SPDEF expression was increased at sites of goblet cell hyperplasia caused by IL-13 and dust mite allergen in a process that was dependent upon STAT-6. SPDEF was induced following intratracheal allergen exposure and after Th2 cytokine stimulation and was sufficient to cause goblet cell differentiation of Clara cells in vivo. PMID:17347682

Respiratory allergy to Blomia tropicalis: Immune response in four syngeneic mouse strains and assessment of a low allergen-dose, short-term experimental model

PubMed Central

2010-01-01

Background The dust mite Blomia tropicalis is an important source of aeroallergens in tropical areas. Although a mouse model for B. tropicalis extract (BtE)-induced asthma has been described, no study comparing different mouse strains in this asthma model has been reported. The relevance and reproducibility of experimental animal models of allergy depends on the genetic background of the animal, the molecular composition of the allergen and the experimental protocol. Objectives This work had two objectives. The first was to study the anti-B. tropicalis allergic responses in different mouse strains using a short-term model of respiratory allergy to BtE. This study included the comparison of the allergic responses elicited by BtE with those elicited by ovalbumin in mice of the strain that responded better to BtE sensitization. The second objective was to investigate whether the best responder mouse strain could be used in an experimental model of allergy employing relatively low BtE doses. Methods Groups of mice of four different syngeneic strains were sensitized subcutaneously with 100 μg of BtE on days 0 and 7 and challenged four times intranasally, at days 8, 10, 12, and 14, with 10 μg of BtE. A/J mice, that were the best responders to BtE sensitization, were used to compare the B. tropicalis-specific asthma experimental model with the conventional experimental model of ovalbumin (OVA)-specific asthma. A/J mice were also sensitized with a lower dose of BtE. Results Mice of all strains had lung inflammatory-cell infiltration and increased levels of anti-BtE IgE antibodies, but these responses were significantly more intense in A/J mice than in CBA/J, BALB/c or C57BL/6J mice. Immunization of A/J mice with BtE induced a more intense airway eosinophil influx, higher levels of total IgE, similar airway hyperreactivity to methacholine but less intense mucous production, and lower levels of specific IgE, IgG1 and IgG2 antibodies than sensitization with OVA. Finally, immunization with a relatively low BtE dose (10 μg per subcutaneous injection per mouse) was able to sensitize A/J mice, which were the best responders to high-dose BtE immunization, for the development of allergy-associated immune and lung inflammatory responses. Conclusions The described short-term model of BtE-induced allergic lung disease is reproducible in different syngeneic mouse strains, and mice of the A/J strain was the most responsive to it. In addition, it was shown that OVA and BtE induce quantitatively different immune responses in A/J mice and that the experimental model can be set up with low amounts of BtE. PMID:20433763

[Animal models for assessment of GMO allergenicity: advantages and limitations].

PubMed

Adel-Patient, K; Wal, J M

2004-03-01

Incidence of IgE-mediated allergic reactions to foods is increasing as well as the severity of associated symptoms and numerous foods are now incriminated, probably in relation with modifications of dietary habits and increased exposure to new or modified food ingredients. Therefore, the introduction on the market of food composed of or derived from genetically modified organisms (GMOs) raised the question of their potential allergenicity. Particularly with regards to the allergenicity of a newly expressed protein, it is necessary to obtain, from several steps in the risk assessment process, a cumulative body of evidence which minimises any uncertainty. This may include the use of animal model despite no fully reliable validated model is available yet. Such animal models should allow to address 3 major issues: Is the novel protein a sensitizer, i.e. does it possess intrinsic properties that allow to sensitize a predisposed individual? Is the protein an elicitor i.e. is it able to elicit an allergic reaction in a sensitised individual? And is the protein an adjuvant, i.e. can it facilitate or enhance the sensitisation to an other protein? Animal models under investigation currently include mice, rats and guinea pigs but models such as dogs and swine also appeared a few years ago. The aim is to mimic the mechanism and characteristics of the sensitisation phase and/or the elicitation phase of the allergic reaction as it occurs in atopic humans. They are necessary because sensitisation studies can obviously not be done in human and because in vitro tests cannot reproduce the complexity of the immune system. We propose a mouse model which mimics both phases of the allergic reaction. It has permitted to evidence that biochemical and clinical manifestations occuring during the active phases of the allergic reaction differ according to the structure of the allergen used for the challenge. This may allow to compare the allergenic potential of a genetically modified protein with that of the conventional one and to identify possible unintended effects. However, pathogenesis of food allergy in human is very complex and multifactorial, including individual differences in susceptibility, environmental factors, conditions of exposure, ... No animal model can take into account all these factors and allow a reliable prediction of the prevalence and severity of allergic reactions which would result from the exposure to a (novel) protein. Nevertheless, point by point analysis using the different models available may provide useful informations on the potential allergenicity of a novel protein.

Emerging Skin T-Cell Functions in Response to Environmental Insults

PubMed Central

Suwanpradid, Jutamas; Holcomb, Zachary E.; MacLeod, Amanda S.

2017-01-01

Skin is the primary barrier between the body and the outside world, functioning not only as a physical barrier, but also as an immunologic first line of defense. A large number of T cells populate the skin. This review highlights the ability of these cutaneous T cells to regulate skin-specific environmental threats, including microbes, injuries, solar UV radiation, and allergens. Since much of this knowledge has been advanced from murine studies, we focus our review on how the mouse state has informed the human state, emphasizing the key parallels and differences. PMID:27784595

Skin test sensitivity to mouse predicts allergic symptoms to nasal challenge in urban adults.

PubMed

Chong, Laura K; Ong, Mary Jane; Curtin-Brosnan, Jean; Matsui, Elizabeth C

2010-01-01

Epidemiologic studies have shown an association between mouse allergen exposure and asthma morbidity among urban populations, but confirmatory challenge studies in community populations have not been performed. This study was designed to examine the clinical relevance of mouse sensitization using a nasal challenge model. Forty-nine urban adults with asthma underwent skin-prick testing (SPT) and intradermal testing (IDT) with mouse epithelia extract. A positive SPT was defined as a net wheal size ≥3 mm and a positive IDT was defined as a net wheal size ≥6 mm using a 1:100 dilution of extract (1:10 w/v was obtained from Greer Laboratories (Lenoir, NC) as a single lot [Mus m 1 concentration = 2130 ng/mL]). Mouse-specific IgE (m-IgE) was measured by ImmunoCAP (Phadia, Uppsala, Sweden). Nasal challenge was performed with increasing concentrations of mouse epithelia extract and symptoms were assessed by visual analog scale. A positive challenge was defined as a 20-mm increase in the scale. The age range of the 49 participants was 18-50 years; 41% were men and 86% were black. Fourteen participants were SPT(+) to mouse, 15 participants were SPT(-) but (IDT(+)), and 20 participants were negative on both SPT(-) and IDT(-) (SPT(-)/IDT(-)). Sixty-four percent of the SPT(+) group, 40% of the IDT(+) group, and 20% of the SPT(-)/IDT(-) group had a positive nasal challenge. Sixty-seven percent (10/15) of those who were either SPT(+) or m-IgE(+) had a positive nasal challenge. SPT or the combination of SPT plus m-IgE performed best in diagnosing mouse allergy. The great majority of mouse-sensitized urban adults with asthma appear to have clinically relevant sensitization. Urban adults with asthma should be evaluated for mouse sensitization using SPT or SPT plus m-IgE testing.

The Role of COX-2 in the Inflammatory and Fibrotic Response in the Lung Following Exposure to Multi-Walled Carbon Nanotubes

NASA Astrophysics Data System (ADS)

Sayers, Brian C.

Exposure to multiwalled carbon nanotubes (MWCNT) has been demonstrated to exacerbate airway inflammation and fibrosis in allergen-challenged mouse model. These data have led to concern that individuals with asthma could represent a susceptible population to adverse health effects following exposure to MWCNT, and possibly other engineered nanoparticles. Asthma pathogenesis is caused by the interaction of a complex genetic predisposition and environmental exposures. Because chronic airway inflammation is common to all asthma phenotypes, it is logical to investigate genes that are involved in inflammatory pathways in order to understand the genetic basis of asthma. The metabolism of arachidonic acid by cyclooxygenase (COX) enzymes is the rate-determining step in the synthesis of prostanoids, which are biologically active lipids that are important modulators of inflammation. Based on the role of COX enzymes in inflammatory pathways, we sought to investigate how COX enzymes are involved in the inflammatory response following MWCNT exposure in asthmatic airways. We report that MWCNT significantly exacerbated allergen-induced airway inflammation and mucus cell metaplasia in COX-2 deficient mice compared to wild type mice. In addition, MWCNTs significantly enhanced allergen-induced cytokines involved in Th2 (IL-13, IL-5), Th1 (CXCL10), and Th17 (IL-17A) inflammatory responses in COX-2 deficient mice but not in WT mice. We conclude that exacerbation of allergen-induced airway inflammation and mucus cell metaplasia by MWCNTs is enhanced by deficiency in COX-2 and associated with activation of a mixed Th1/Th2/Th17 immune response. Based on our observation that COX-2 deficient mice developed a mixed Th immune response following MWCNT exposure, we sought to evaluate how cytokines associated with different Th immune responses alter COX expression following MWCNT exposure. For this study, a mouse macrophage cell line (RAW264.7) was used because MWCNT were largely sequestered within alveolar macrophages with 24 hours after aspiration in mice. We report that the Th1 cytokine interferon gamma (IFNgamma) causes decreased COX-1 expression but increased prostaglandin E2 (PGE 2) production in mouse macrophages exposed to nickel nanoparticles (NiNP), a residual impurity found in MWCNT from the catalytic synthesis process. NiNP exposure alone increased COX-2 and decreased COX-1 in the absence of exogenous cytokines. IFNgamma further reduced COX-1 levels suppressed by NiNP. IL-4, IL-13, or IL-17 did not reduce COX-1 expression alone or in combination with NiNP. Exogenous PGE2 enhanced NiNP- or IFN-gamma-mediated COX-1 suppression. Pharmacologic inhibition of ERK1,2 or JAK/STAT-1 cell signaling pathways inhibited PGE2 production in all dose groups and restored COX-1 expression in cells treated with IFNgamma and NiNP. These data show that PGE2 production is induced in macrophages exposed to IFNgamma and NiNP and suggest that macrophages could be an important source of the anti-inflammatory mediator PGE2 following nanoparticle exposure in a Th1 immune microenvironment. In summary, these studies highlight an important role for COX enzymes in regulating inflammation in response to engineered nanoparticles and show that prostanoid production in response to nanoparticle exposure could be determined in part by the Th immune microenvironment.

Navigating through the Jungle of Allergens: Features and Applications of Allergen Databases.

PubMed

Radauer, Christian

2017-01-01

The increasing number of available data on allergenic proteins demanded the establishment of structured, freely accessible allergen databases. In this review article, features and applications of 6 of the most widely used allergen databases are discussed. The WHO/IUIS Allergen Nomenclature Database is the official resource of allergen designations. Allergome is the most comprehensive collection of data on allergens and allergen sources. AllergenOnline is aimed at providing a peer-reviewed database of allergen sequences for prediction of allergenicity of proteins, such as those planned to be inserted into genetically modified crops. The Structural Database of Allergenic Proteins (SDAP) provides a database of allergen sequences, structures, and epitopes linked to bioinformatics tools for sequence analysis and comparison. The Immune Epitope Database (IEDB) is the largest repository of T-cell, B-cell, and major histocompatibility complex protein epitopes including epitopes of allergens. AllFam classifies allergens into families of evolutionarily related proteins using definitions from the Pfam protein family database. These databases contain mostly overlapping data, but also show differences in terms of their targeted users, the criteria for including allergens, data shown for each allergen, and the availability of bioinformatics tools. © 2017 S. Karger AG, Basel.

Changes in voiding behavior in a mouse model of Alzheimer’s disease

PubMed Central

Biallosterski, B. T.; Prickaerts, J.; Rahnama’i, M. S.; de Wachter, S.; van Koeveringe, G. A.; Meriaux, C.

2015-01-01

Besides cognitive decline and behavioral alteration, urinary incontinence often occurs in patients suffering from Alzheimer’s disease (AD). To determine whether the transgenic mouse model of AD, APP/PS1 (APPSL/PS1M146L) mouse, shows alteration of the urinary bladder function and anxiety, as for patients with AD, we examined the urinary marking behavior in relation to affective behavior. At 18 months of age voiding behavior of APP/PS1 and wild type (WT) mice was assessed by using a modified filter paper assay in combination with video tracing, with the cage divided into a center and corner zones. Anxiety-related behavior and locomotion were respectively tested in an elevated zero maze (EZM) and an open field (OF). The APP/PS1 mice urinated more in the center zone than the WT mice. The total volume of markings was significantly lower in the APP/PS1 mice. In both groups, the average volume of a marking in the corner zone was larger than in the center zone. In the EZM, the APP/PS1 mice spent less time in the open arms of the arena, considered as anxiogenic zones, than the WT mice. During the OF task, the APP/PS1 mice covered a longer distance than the WT mice. These findings show that the APP/PS1 mice have a different voiding behavior compared to the WT mice, i.e., urinating with small volumes and voiding in the center of the cage, and suggest that increased locomotor activity and anxiety-related behaviors are factors in the change in voiding pattern in the APP/PS1 mouse. PMID:26379542

Bilirubin nanoparticles ameliorate allergic lung inflammation in a mouse model of asthma.

PubMed

Kim, Dong Eon; Lee, Yonghyun; Kim, MinGyo; Lee, Soyoung; Jon, Sangyong; Lee, Seung-Hyo

2017-09-01

Although asthma, a chronic inflammatory airway disease, is relatively well-managed by inhaled corticosteroids, the side effects associated with the long-term use of these agents precipitate the need for alternative therapeutic options based on differing modes of action. Bilirubin, a potent endogenous antioxidant, and anti-inflammatory molecule have been shown to ameliorate asthmatic symptoms; however, its clinical translation has been limited owing to its water insolubility and associated potential toxicity. Here we report the first application of bilirubin-based nanoparticles (BRNPs) as a nanomedicine for the treatment of allergic lung inflammatory disease. BRNPs were prepared directly from self-assembly of PEGylated bilirubin in aqueous solution and had a hydrodynamic diameter of ∼100 nm. Because allergen-specific type 2 T-helper (Th2) cells play a key role in the pathogenesis and progression of allergic asthma, the effects of BRNPs on Th2 immune responses were investigated both in vivo and in vitro. BRNPs after intravenous injection (i.v.) showed much higher serum concentration and a longer circulation time of bilirubin than the intraperitoneal injection (i.p.) of BRNPs or unconjugated bilirubin (UCB). The anti-asthmatic effects of BRNPs were assessed in a mouse model of allergen-induced asthma. Compared with UCB, treatment with BRNPs suppressed the symptoms of experimental allergic asthma and dramatically ameliorated Th2-related allergic lung inflammation. Consistent with these results, BRNPs caused a reduction of Th2 cell populations and the expression of related cytokines by antibody-stimulated CD4 + T cells in vitro. Therefore, our results establish BRNPs as an important immunomodulatory agent that may be useful as a therapeutic for allergic lung inflammatory disease and other immune-mediated disorders. Copyright © 2017 Elsevier Ltd. All rights reserved.

Acinetobacter baumannii Infection Inhibits Airway Eosinophilia and Lung Pathology in a Mouse Model of Allergic Asthma

PubMed Central

Qiu, Hongyu; KuoLee, Rhonda; Harris, Greg; Zhou, Hongyan; Miller, Harvey; Patel, Girishchandra B.; Chen, Wangxue

2011-01-01

Allergic asthma is a dysregulation of the immune system which leads to the development of Th2 responses to innocuous antigens (allergens). Some infections and microbial components can re-direct the immune response toward the Th1 response, or induce regulatory T cells to suppress the Th2 response, thereby inhibiting the development of allergic asthma. Since Acinetobacter baumannii infection can modulate lung cellular and cytokine responses, we studied the effect of A. baumannii in modulating airway eosinophilia in a mouse model of allergic asthma. Ovalbumin (OVA)-sensitized mice were treated with live A. baumannii or phosphate buffered saline (PBS), then intranasally challenged with OVA. Compared to PBS, A. baumannii treatment significantly reduced pulmonary Th2 cytokine and chemokine responses to OVA challenge. More importantly, the airway inflammation in A. baumannii-treated mice was strongly suppressed, as seen by the significant reduction of the proportion and the total number of eosinophils in the bronchoalveolar lavage fluid. In addition, A. baumannii-treated mice diminished lung mucus overproduction and pathology. However, A. baumannii treatment did not significantly alter systemic immune responses to OVA. Serum OVA-specific IgE, IgG1 and IgG2a levels were comparable between A. baumannii- and PBS-treated mice, and tracheobronchial lymph node cells from both treatment groups produced similar levels of Th1 and Th2 cytokines in response to in vitro OVA stimulation. Moreover, it appears that TLR-4 and IFN-γ were not directly involved in the A. baumannii-induced suppression of airway eosinophilia. Our results suggest that A. baumannii inhibits allergic airway inflammation by direct suppression of local pulmonary Th2 cytokine responses to the allergen. PMID:21789200

Functional Effects of TGF-beta1 on Mesenchymal Stem Cell Mobilization in Cockroach Allergen Induced Asthma

PubMed Central

Xian, Lingling; Li, Changjun; Xu, Ting; Plunkett, Beverly; Huang, Shau-Ku; Wan, Mei; Cao, Xu

2014-01-01

Mesenchymal stem cells (MSCs) have been suggested to participate in immune regulation and airway repair/remodeling. Transforming growth factor β1 (TGFβ1) is critical in the recruitment of stem/progenitor cells for tissue repair, remodeling and cell differentiation. In this study, we sought to investigate the role of TGFβ1 in MSC migration in allergic asthma. We examined nestin expression (a marker for MSCs) and TGFβ1 signaling activation in airways in cockroach allergen (CRE) induced mouse models. Compared with control mice, there were increased nestin+ cells in airways, and higher levels of active TGFβ1 in serum and p-Smad2/3 expression in lungs of CRE-treated mice. Increased activation of TGFβ1 signaling was also found in CRE-treated MSCs. We then assessed MSC migration induced by conditioned medium (ECM) from CRE-challenged human epithelium in air/liquid interface (ALI) culture in Transwell assays. MSC migration was stimulated by ECM, but was significantly inhibited by either TGFβ1 neutralizing antibody or TβR1 inhibitor. Intriguingly, increased migration of MSCs from blood and bone marrow to the airway was also observed after systemic injection of GFP+-MSCs, and from bone marrow of Nes-GFP mice following CRE challenge. Furthermore, TGFβ1 neutralizing antibody inhibited the CRE-induced MSC recruitment, but promoted airway inflammation. Finally, we investigated the role of MSCs in modulating CRE induced T cell response, and found that MSCs significantly inhibited CRE-induced inflammatory cytokine secretion (IL-4, IL13, IL17 and IFN-γ) by CD4+ T cells. These results suggest that TGFβ1 may be a key pro-migratory factor in recruiting MSCs to the airways in mouse models of asthma. PMID:24711618

Plethysmography Phenotype QTL in Mice Before and After Allergen Sensitization and Challenge.

PubMed

Kelada, Samir N P

2016-09-08

Allergic asthma is common airway disease that is characterized in part by enhanced airway constriction in response to nonspecific stimuli. Genome-wide association studies have identified multiple loci associated with asthma risk in humans, but these studies have not accounted for gene-environment interactions, which are thought to be important factors in asthma. To identify quantitative trait loci (QTL) that regulate responses to a common human allergen, we applied a house dust mite mouse (HDM) model of allergic airway disease (AAD) to 146 incipient lines of the Collaborative Cross (CC) and the CC founder strains. We employed a longitudinal study design in which mice were phenotyped for response to the bronchoconstrictor methacholine both before and after HDM sensitization and challenge using whole body plethysmography (WBP). There was significant variation in methacholine responsiveness due to both strain and HDM treatment, as reflected by changes in the WBP parameter enhanced pause. We also found that distinct QTL regulate baseline [chromosome (Chr) 18] and post-HDM (Chr 19) methacholine responsiveness and that post-HDM airway responsiveness was correlated with other features of AAD. Finally, using invasive measurements of airway mechanics, we tested whether the Chr 19 QTL affects lung resistance per se using C57BL/6J mice and a consomic strain but found that QTL haplotype did not affect lung resistance. We conclude that aspects of baseline and allergen-induced methacholine responsiveness are associated with genetic variation, and that robust detection of airway resistance QTL in genetically diverse mice will be facilitated by direct measurement of airway mechanics. Copyright © 2016 Kelada.

Plethysmography Phenotype QTL in Mice Before and After Allergen Sensitization and Challenge

DOE PAGES

Kelada, Samir N. P.

2016-07-22

Allergic asthma is common airway disease that is characterized in part by enhanced airway constriction in response to nonspecific stimuli. Genome-wide association studies have identified multiple loci associated with asthma risk in humans, but these studies have not accounted for gene–environment interactions, which are thought to be important factors in asthma. To identify quantitative trait loci (QTL) that regulate responses to a common human allergen, we applied a house dust mite mouse (HDM) model of allergic airway disease (AAD) to 146 incipient lines of the Collaborative Cross (CC) and the CC founder strains. We employed a longitudinal study design inmore » which mice were phenotyped for response to the bronchoconstrictor methacholine both before and after HDM sensitization and challenge using whole body plethysmography (WBP). There was significant variation in methacholine responsiveness due to both strain and HDM treatment, as reflected by changes in the WBP parameter enhanced pause. We also found that distinct QTL regulate baseline [chromosome (Chr) 18] and post-HDM (Chr 19) methacholine responsiveness and that post-HDM airway responsiveness was correlated with other features of AAD. Finally, using invasive measurements of airway mechanics, we tested whether the Chr 19 QTL affects lung resistance per se using C57BL/6J mice and a consomic strain but found that QTL haplotype did not affect lung resistance. We conclude that aspects of baseline and allergen-induced methacholine responsiveness are associated with genetic variation, and that robust detection of airway resistance QTL in genetically diverse mice will be facilitated by direct measurement of airway mechanics.« less

Plethysmography Phenotype QTL in Mice Before and After Allergen Sensitization and Challenge

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kelada, Samir N. P.

Allergic asthma is common airway disease that is characterized in part by enhanced airway constriction in response to nonspecific stimuli. Genome-wide association studies have identified multiple loci associated with asthma risk in humans, but these studies have not accounted for gene–environment interactions, which are thought to be important factors in asthma. To identify quantitative trait loci (QTL) that regulate responses to a common human allergen, we applied a house dust mite mouse (HDM) model of allergic airway disease (AAD) to 146 incipient lines of the Collaborative Cross (CC) and the CC founder strains. We employed a longitudinal study design inmore » which mice were phenotyped for response to the bronchoconstrictor methacholine both before and after HDM sensitization and challenge using whole body plethysmography (WBP). There was significant variation in methacholine responsiveness due to both strain and HDM treatment, as reflected by changes in the WBP parameter enhanced pause. We also found that distinct QTL regulate baseline [chromosome (Chr) 18] and post-HDM (Chr 19) methacholine responsiveness and that post-HDM airway responsiveness was correlated with other features of AAD. Finally, using invasive measurements of airway mechanics, we tested whether the Chr 19 QTL affects lung resistance per se using C57BL/6J mice and a consomic strain but found that QTL haplotype did not affect lung resistance. We conclude that aspects of baseline and allergen-induced methacholine responsiveness are associated with genetic variation, and that robust detection of airway resistance QTL in genetically diverse mice will be facilitated by direct measurement of airway mechanics.« less

An assessment of indoor air quality in recent Mexican immigrant housing in Commerce City, Colorado

NASA Astrophysics Data System (ADS)

Miller, Shelly L.; Scaramella, Peter; Campe, Joseph; Goss, Cynthia W.; Diaz-Castillo, Sandra; Hendrikson, Ed; DiGuiseppi, Carolyn; Litt, Jill

An indoor air quality assessment was conducted on 100 homes of recent Mexican immigrants in Commerce City, Colorado, an urban industrial community north of Denver. Head of households were administered a family health survey, filled out an activity diary, and participated in a home inspection. Carbon monoxide (CO) and carbon dioxide (CO 2) were measured for 24 h inside the main living area and outside of the homes. Harvard Impactors were used to collect 24-h samples of PM 2.5 at the same locations for gravimetric analysis. Dust samples were collected by vacuuming carpeting and flooring at four locations within the home and analyzed by ELISA for seven allergens. Mean indoor and outdoor PM 2.5 levels were 27.2 and 8.5 μg m -3, respectively. Indoor PM 2.5 and CO 2 were elevated in homes for which the number of hours with door/window open was zero compared to homes in which the number of hours was high (>15 h). Indoor PM 2.5 levels did not correlate with outdoor levels and tended to increase with number of inhabitants, and results indicate that the source of indoor particles were occupants and their activities, excluding smoking and cooking. Mean indoor CO 2 and CO levels were 1170 and 2.4 ppm, respectively. Carbon monoxide was higher than the 24-h National Ambient Air Quality Standard in 3 of the homes. The predominant allergens were cat ( Fel d 1) and mouse ( Mus m 1) allergens, found in 20 and 34 homes, respectively.

Compartmental and temporal dynamics of chronic inflammation and airway remodelling in a chronic asthma mouse model.

PubMed

Alrifai, Mohammed; Marsh, Leigh M; Dicke, Tanja; Kılıç, Ayse; Conrad, Melanie L; Renz, Harald; Garn, Holger

2014-01-01

Allergic asthma is associated with chronic airway inflammation and progressive airway remodelling. However, the dynamics of the development of these features and their spontaneous and pharmacological reversibility are still poorly understood. We have therefore investigated the dynamics of airway remodelling and repair in an experimental asthma model and studied how pharmacological intervention affects these processes. Using BALB/c mice, the kinetics of chronic asthma progression and resolution were characterised in absence and presence of inhaled corticosteroid (ICS) treatment. Airway inflammation and remodelling was assessed by the analysis of bronchoalveolar and peribronichal inflammatory cell infiltrate, goblet cell hyperplasia, collagen deposition and smooth muscle thickening. Chronic allergen exposure resulted in early (goblet cell hyperplasia) and late remodelling (collagen deposition and smooth muscle thickening). After four weeks of allergen cessation eosinophilic inflammation, goblet cell hyperplasia and collagen deposition were resolved, full resolution of lymphocyte inflammation and smooth muscle thickening was only observed after eight weeks. ICS therapy when started before the full establishment of chronic asthma reduced the development of lung inflammation, decreased goblet cell hyperplasia and collagen deposition, but did not affect smooth muscle thickening. These effects of ICS on airway remodelling were maintained for a further four weeks even when therapy was discontinued. Utilising a chronic model of experimental asthma we have shown that repeated allergen exposure induces reversible airway remodelling and inflammation in mice. Therapeutic intervention with ICS was partially effective in inhibiting the transition from acute to chronic asthma by reducing airway inflammation and remodelling but was ineffective in preventing smooth muscle hypertrophy.

Expression, purification, and characterization of almond (Prunus dulcis) allergen Pru du 4

USDA-ARS?s Scientific Manuscript database

Biochemical characterizations of food allergens are required for understanding the allergenicity of food allergens. Such studies require a relatively large amount of highly purified allergens. Profilins from numerous species are known to be allergens, including food allergens, such as almond (Prunus...

Minor allergen patterns in birch pollen allergen products-A question of pollen?

PubMed

Zimmer, J; Döring, S; Strecker, D; Trösemeier, J H; Hanschmann, K M; Führer, F; Vieths, S; Kaul, S

2017-08-01

Contrary to the scientific differentiation between major and minor allergens, the regulatory framework controlling allergen products in the EU distinguishes relevant and non-relevant allergens. Given the lack of knowledge on their clinical relevance, minor allergens are usually not controlled by allergen product specifications. Especially, in birch pollen (BP) allergen products, minor allergens are commonly disregarded. To quantify three minor allergens in BP allergen products from different manufacturers and to assess the influence of the utilized BP on minor allergen patterns. Apart from common quality parameters such as Bet v 1 content, Bet v 4, Bet v 6 and Bet v 7 were quantified in 70 BP allergen product batches from six manufacturers, using ELISA systems developed in-house. Batch-to-batch variability was checked for agreement with a variability margin of 50%-200% from mean of the given batches for individual allergen content. Subsequently, minor allergen patterns were generated via multidimensional scaling and related to information on the pollen lots used in production of the respective product batches. Like the already established Bet v 4 ELISA, the ELISA systems for quantification of Bet v 6 and Bet v 7 were successfully validated. Differences in minor allergen content between products and batch-to-batch consistency were observed. Correlations between minor and major allergen content were low to moderate. About 20% of batches exceeded the variability margin for at least one minor allergen. Interestingly, these fluctuations could not in all cases be linked to the use of certain BP lots. The impact of the observed minor allergen variability on safety and efficacy of BP allergen products can currently not be estimated. As the described differences could only in few cases be related to the used pollen lots, it is evident that additional factors influence minor allergens in BP allergen products. © 2017 John Wiley & Sons Ltd.

Crystal structure of peanut (Arachis hypogaea) allergen Ara h 5

USDA-ARS?s Scientific Manuscript database

Profilins from numerous species are known to be allergens, including food allergens, such as peanut (Arachis hypogaea) allergen Ara h 5, and pollen allergens, such as birch allergen Bet v 2. Patients with pollen allergy can also cross-react to peanut. Structural characterization of allergens will al...

Intrauterine sensitization of allergen-specific IgE analyzed by a highly sensitive new allergen microarray.

PubMed

Kamemura, Norio; Tada, Hitomi; Shimojo, Naoki; Morita, Yoshinori; Kohno, Yoichi; Ichioka, Takao; Suzuki, Koichi; Kubota, Kenji; Hiyoshi, Mineyoshi; Kido, Hiroshi

2012-07-01

To design a rational allergy prevention program, it is important to determine whether allergic sensitization starts in utero under the maternal immune system. To investigate the origin of allergen-specific IgE antibodies in cord blood (CB) and maternofetal transfer of immunoglobulins. The levels of food and inhalant allergen-specific IgE, IgA, IgG, and IgG(4) antibodies in CB and maternal blood (MB) from 92 paired neonates and mothers were measured by using a novel allergen microarray of diamond-like-carbon-coated chip, with high-sensitivity detection of allergen-specific antibodies and allergen profiles. The levels of allergen-specific IgE antibodies against food and inhalant allergens and allergen profiles were identical in CB and newborn blood, but the levels and profiles, specifically against inhalant allergens, were different from those in MB. The level of allergen-specific IgA antibodies was below the detection levels in CB despite clear detection in MB. Therefore, contamination with MB in CB was excluded on the basis of extremely low levels of IgA antibodies in CB and the obvious mismatch of the allergen-specific IgE and IgA profiles between CB and MB. However, the levels of allergen-specific IgG and IgG(4) antibodies and their allergen profiles were almost identical in both MB and CB. Allergen-specific levels of IgE and IgA antibodies and their allergen profiles analyzed by the diamond-like-carbon allergen chip indicate that IgE antibodies in CB are of fetal origin. Food-allergen specific IgE antibodies were detected more often than inhalant-allergen specific IgE antibodies in CB, the reason of which remains unclarified. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Evolutionary distance from human homologs reflects allergenicity of animal food proteins.

PubMed

Jenkins, John A; Breiteneder, Heimo; Mills, E N Clare

2007-12-01

In silico analysis of allergens can identify putative relationships among protein sequence, structure, and allergenic properties. Such systematic analysis reveals that most plant food allergens belong to a restricted number of protein superfamilies, with pollen allergens behaving similarly. We have investigated the structural relationships of animal food allergens and their evolutionary relatedness to human homologs to define how closely a protein must resemble a human counterpart to lose its allergenic potential. Profile-based sequence homology methods were used to classify animal food allergens into Pfam families, and in silico analyses of their evolutionary and structural relationships were performed. Animal food allergens could be classified into 3 main families--tropomyosins, EF-hand proteins, and caseins--along with 14 minor families each composed of 1 to 3 allergens. The evolutionary relationships of each of these allergen superfamilies showed that in general, proteins with a sequence identity to a human homolog above approximately 62% were rarely allergenic. Single substitutions in otherwise highly conserved regions containing IgE epitopes in EF-hand parvalbumins may modulate allergenicity. These data support the premise that certain protein structures are more allergenic than others. Contrasting with plant food allergens, animal allergens, such as the highly conserved tropomyosins, challenge the capability of the human immune system to discriminate between foreign and self-proteins. Such immune responses run close to becoming autoimmune responses. Exploiting the closeness between animal allergens and their human homologs in the development of recombinant allergens for immunotherapy will need to consider the potential for developing unanticipated autoimmune responses.

Food Allergens: Is There a Correlation between Stability to Digestion and Allergenicity?

PubMed

Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

2016-07-03

Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. It has not yet been established what makes a dietary protein a food allergen. Several characteristics have been proposed to be shared by food allergens. One of these is resistance to digestion. This paper reviews data from digestibility studies on purified food allergens and evaluates the predictive value of digestibility tests on the allergenic potential. We point out that food allergens do not necessarily resist digestion. We discuss how the choice of in vitro digestibility assay condition and the method used for detection of residual intact protein as well as fragments hereof may greatly influence the outcome as well as the interpretation of results. The finding that digests from food allergens may retain allergenicity, stresses the importance of using immunological assays for evaluating the allergenic potential of food allergen digestion products. Studies assessing the allergenicity of digestion products, by either IgE-binding, elicitation or sensitizing capacity, shows that digestion may abolish, decrease, have no effect, or even increase the allergenicity of food allergens. Therefore, the predictive value of the pepsin resistance test for assessing the allergenic potential of novel proteins can be questioned.

Allergen Sensitization Pattern by Sex: A Cluster Analysis in Korea.

PubMed

Ohn, Jungyoon; Paik, Seung Hwan; Doh, Eun Jin; Park, Hyun-Sun; Yoon, Hyun-Sun; Cho, Soyun

2017-12-01

Allergens tend to sensitize simultaneously. Etiology of this phenomenon has been suggested to be allergen cross-reactivity or concurrent exposure. However, little is known about specific allergen sensitization patterns. To investigate the allergen sensitization characteristics according to gender. Multiple allergen simultaneous test (MAST) is widely used as a screening tool for detecting allergen sensitization in dermatologic clinics. We retrospectively reviewed the medical records of patients with MAST results between 2008 and 2014 in our Department of Dermatology. A cluster analysis was performed to elucidate the allergen-specific immunoglobulin (Ig)E cluster pattern. The results of MAST (39 allergen-specific IgEs) from 4,360 cases were analyzed. By cluster analysis, 39items were grouped into 8 clusters. Each cluster had characteristic features. When compared with female, the male group tended to be sensitized more frequently to all tested allergens, except for fungus allergens cluster. The cluster and comparative analysis results demonstrate that the allergen sensitization is clustered, manifesting allergen similarity or co-exposure. Only the fungus cluster allergens tend to sensitize female group more frequently than male group.

Activation of mas-related G-protein-coupled receptors by the house dust mite cysteine protease Der p1 provides a new mechanism linking allergy and inflammation.

PubMed

Reddy, Vemuri B; Lerner, Ethan A

2017-10-20

Cysteine and serine proteases function via protease-activated and mas-related G-protein-coupled receptors (Mrgprs) to contribute to allergy and inflammation. Der p1 is a cysteine protease and major allergen from the house dust mite and is associated with allergic rhinitis and allergic asthma. Der p1 activates protease-activated receptor 2 and induces the release of the pro-inflammatory cytokine IL-6 from cells. However, the possibility that Der p1 acts on Mrgprs has not been considered. We report here that ratiometric calcium imaging reveals that Der p1 activates the human receptor MRGPRX1 and the mouse homolog MrgprC11, implicated previously in itch. Der p1 cleavage of N-terminal receptor peptides followed by site-directed mutagenesis of the cleavage sites links receptor activation to specific amino acid residues. Der p1 also induced the release of IL-6 from heterologous cells expressing MRGPRX1. In summary, activation of Mrgprs by the allergen Der p1 may contribute to inflammation. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Modularity in the Organization of Mouse Primary Visual Cortex

PubMed Central

Ji, Weiqing; Gămănuţ, Răzvan; Bista, Pawan; D’Souza, Rinaldo D.; Wang, Quanxin; Burkhalter, Andreas

2015-01-01

SUMMARY Layer 1 (L1) of primary visual cortex (V1) is the target of projections from many brain regions outside of V1. We found that inputs to the non-columnar mouse V1 from the dorsal lateral geniculate nucleus and feedback projections from multiple higher cortical areas to L1 are patchy. The patches are matched to a pattern of M2 muscarinic acetylcholine receptor expression at fixed locations of mouse, rat and monkey V1. Neurons in L2/3 aligned with M2-rich patches have high spatial acuity whereas cells in M2-poor zones exhibited high temporal acuity. Together M2+ and M2− zones form constant-size domains that are repeated across V1. Domains map subregions of the receptive field, such that multiple copies are contained within the point image. The results suggest that the modular network in mouse V1 selects spatiotemporally distinct clusters of neurons within the point image for top-down control and differential routing of inputs to cortical streams. PMID:26247867

[Vaccination with Mycobacterium: can it cure allergies?].

PubMed

Louis, R

2003-06-01

In developed countries, the prevalence of tuberculosis has evolved in an opposite direction as to the one of allergy over the last century. The immunological response is mainly Th1 in tuberculosis while it features a Th2 pattern in allergy. Vaccination with BCG in early life is associated with a reduction in the prevalence of allergy later in childhood. In an experimental mouse model of asthma, administration of BCG or killed Mycobacterium vaccae inhibits the sensitisation process as well as the bronchial inflammation and hyperresponsiveness that follows allergen exposure. In children and adolescents suffering from atopic dermatitis, subcutaneous injection of killed Mycobacterium vaccae attenuates the severity of skin lesions.

Specific IgE and IgG measured by the MeDALL allergen-chip depend on allergen and route of exposure: The EGEA study.

PubMed

Siroux, Valérie; Lupinek, Christian; Resch, Yvonne; Curin, Mirela; Just, Jocelyne; Keil, Thomas; Kiss, Renata; Lødrup Carlsen, Karin; Melén, Erik; Nadif, Rachel; Pin, Isabelle; Skrindo, Ingebjørg; Vrtala, Susanne; Wickman, Magnus; Anto, Josep Maria; Valenta, Rudolf; Bousquet, Jean

2017-02-01

The nature of allergens and route and dose of exposure may affect the natural development of IgE and IgG responses. We sought to investigate the natural IgE and IgG responses toward a large panel of respiratory and food allergens in subjects exposed to different respiratory allergen loads. A cross-sectional analysis was conducted in 340 adults of the EGEA (Epidemiological study of the Genetics and Environment of Asthma, bronchial hyperresponsiveness and atopy) (170 with and 170 without asthma) cohort. IgE and IgG responses to 47 inhalant and food allergen components were analyzed in sera using allergen microarray and compared between 5 French regions according to the route of allergen exposure (inhaled vs food allergens). Overall 48.8% of the population had allergen-specific IgE levels of 0.3 ISAC standardized units (ISU) or more to at least 1 of the 47 allergens with no significant differences across the regions. For ubiquitous respiratory allergens (ie, grass, olive/ash pollen, house dust mites), specific IgE did not show marked differences between regions and specific IgG (≥0.5 ISU) was present in most subjects everywhere. For regionally occurring pollen allergens (ragweed, birch, cypress), IgE sensitization was significantly associated with regional pollen exposure. For airborne allergens cross-reacting with food allergens, frequent IgG recognition was observed even in regions with low allergen prevalence (Bet v 1) or for allergens less frequently recognized by IgE (profilins). The variability in allergen-specific IgE and IgG frequencies depends on exposure, route of exposure, and overall immunogenicity of the allergen. Allergen contact by the oral route might preferentially induce IgG responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Molecular features of grass allergens and development of biotechnological approaches for allergy prevention.

PubMed

Devis, Deborah L; Davies, Janet M; Zhang, Dabing

2017-09-01

Allergic diseases are characterized by elevated allergen-specific IgE and excessive inflammatory cell responses. Among the reported plant allergens, grass pollen and grain allergens, derived from agriculturally important members of the Poaceae family such as rice, wheat and barley, are the most dominant and difficult to prevent. Although many allergen homologs have been predicted from species such as wheat and timothy grass, fundamental aspects such as the evolution and function of plant pollen allergens remain largely unclear. With the development of genetic engineering and genomics, more primary sequences, functions and structures of plant allergens have been uncovered, and molecular component-based allergen-specific immunotherapies are being developed. In this review, we aim to provide an update on (i) the distribution and importance of pollen and grain allergens of the Poaceae family, (ii) the origin and evolution, and functional aspects of plant pollen allergens, (iii) developments of allergen-specific immunotherapy for pollen allergy using biotechnology and (iv) development of less allergenic plants using gene engineering techniques. We also discuss future trends in revealing fundamental aspects of grass pollen allergens and possible biotechnological approaches to reduce the amount of pollen allergens in grasses. Copyright © 2017. Published by Elsevier Inc.

Modified Allergens for Immunotherapy.

PubMed

Satitsuksanoa, Pattraporn; Głobińska, Anna; Jansen, Kirstin; van de Veen, Willem; Akdis, Mübeccel

2018-02-16

During the past few decades, modified allergens have been developed for use in allergen-specific immunotherapy (AIT) with the aim to improve efficacy and reduce adverse effects. This review aims to provide an overview of the different types of modified allergens, their mechanism of action and their potential for improving AIT. In-depth research in the field of allergen modifications as well as the advance of recombinant DNA technology have paved the way for improved diagnosis and research on human allergic diseases. A wide range of structurally modified allergens has been generated including allergen peptides, chemically altered allergoids, adjuvant-coupled allergens, and nanoparticle-based allergy vaccines. These modified allergens show promise for the development of AIT regimens with improved safety and long-term efficacy. Certain modifications ensure reduced IgE reactivity and retained T cell reactivity, which facilities induction of immune tolerance to the allergen. To date, multiple clinical trials have been performed using modified allergens. Promising results were obtained for the modified cat, grass and birch pollen, and house dust mite allergens. The use of modified allergens holds promise for improving AIT efficacy and safety. There is however a need for larger clinical studies to reliably assess the added benefit for the patient of using modified allergens for AIT.

484 Allergen Standardisation in Allergens and Allergoids—Challenges and Considerations

PubMed Central

Skinner, Murray; Bullimore, Alan; Hewings, Simon; Swan, Nicola

2012-01-01

Background The range of therapeutics and dosing schedules for allergen preparations and allergoids produced and used clinically are considerable. Standardisation of allergy immunotherapies is considered a positive step; however there are difficulties in identifying universal metrics for standardisation. Many advocate the use of major allergen content whilst others advocate total allergenicity. Additionally as a compounding argument, where major allergen is used, many disagree on what the major allergen is for certain species. Methods Major allergen content measurement allows a consistent recognised measure, and IgE responses of a serum pool are often dominated by IgE against major allergens. However issues such as specificity of different assays toward isoforms and other variants of single allergens often results in diverging allergen contents that can cause unexpected and misleading disparity. Other aspects that increase complication are the relevance to modified allergens, use of adjuvants and differing dosing regimes. Results The major allergen content of key products in different therapeutic formats has been measured. Conclusions This has been performed in conjunction with techniques such as total allergenicity, as allergy treatments and therapeutics require careful characterisation to allow supply of consistent, safe and efficacious products.

Earth Mover's Distance (EMD): A True Metric for Comparing Biomarker Expression Levels in Cell Populations.

PubMed

Orlova, Darya Y; Zimmerman, Noah; Meehan, Stephen; Meehan, Connor; Waters, Jeffrey; Ghosn, Eliver E B; Filatenkov, Alexander; Kolyagin, Gleb A; Gernez, Yael; Tsuda, Shanel; Moore, Wayne; Moss, Richard B; Herzenberg, Leonore A; Walther, Guenther

2016-01-01

Changes in the frequencies of cell subsets that (co)express characteristic biomarkers, or levels of the biomarkers on the subsets, are widely used as indices of drug response, disease prognosis, stem cell reconstitution, etc. However, although the currently available computational "gating" tools accurately reveal subset frequencies and marker expression levels, they fail to enable statistically reliable judgements as to whether these frequencies and expression levels differ significantly between/among subject groups. Here we introduce flow cytometry data analysis pipeline which includes the Earth Mover's Distance (EMD) metric as solution to this problem. Well known as an informative quantitative measure of differences between distributions, we present three exemplary studies showing that EMD 1) reveals clinically-relevant shifts in two markers on blood basophils responding to an offending allergen; 2) shows that ablative tumor radiation induces significant changes in the murine colon cancer tumor microenvironment; and, 3) ranks immunological differences in mouse peritoneal cavity cells harvested from three genetically distinct mouse strains.

The rise of food allergy: Environmental factors and emerging treatments.

PubMed

Benedé, Sara; Blázquez, Ana Belen; Chiang, David; Tordesillas, Leticia; Berin, M Cecilia

2016-05-01

Food allergy has rapidly increased in prevalence, suggesting an important role for environmental factors in disease susceptibility. The immune response of food allergy is characterized by IgE production, and new findings from mouse and human studies indicate an important role of the cytokine IL-9, which is derived from both T cells and mast cells, in disease manifestations. Emerging evidence suggests that route of exposure to food, particularly peanut, is important. Exposure through the skin promotes sensitization while early exposure through the gastrointestinal tract promotes tolerance. Evidence from mouse studies indicate a role of the microbiome in development of food allergy, which is supported by correlative human studies showing a dysbiosis in food allergy. There is no approved treatment for food allergy, but emerging therapies are focused on allergen immunotherapy to provide desensitization, while pre-clinical studies are focused on using adjuvants or novel delivery approaches to improve efficacy and safety of immunotherapy. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Food allergens: molecular and immunological aspects, allergen databases and cross-reactivity.

PubMed

Lorenz, Anne-Regine; Scheurer, Stephan; Vieths, Stefan

2015-01-01

The currently known food allergens are assigned to a relatively small number of protein families. Food allergens grouped into protein families share common functional and structural features that can be attributed to the allergenic potency and potential cross-reactivity of certain proteins. Molecular data, in terms of structural information, biochemical characteristics and clinical relevance for each known allergen, including isoforms and variants, are mainly compiled into four open-access databases. Allergens are designated according to defined criteria by the World Health Organization and the International Union of Immunological Societies Allergen Nomenclature Sub-committee. Food allergies are caused by primary sensitisation to the disease-eliciting food allergens (class I food allergen), or they can be elicited as a consequence of a primary sensitisation to inhalant allergens and subsequent IgE cross-reaction to homologous proteins in food (class II food allergens). Class I and class II allergens display different clinical significance in children and adults and are characterised by different molecular features. In line with this, high stability when exposed to gastrointestinal digestion and heat treatment is attributed to many class I food allergens that frequently induce severe reactions. The stability of a food allergen is determined by its molecular characteristics and can be influenced by structural (chemical) modifications due to thermal processing. Moreover, the immunogenicity and allergenicity of food allergens further depends on specific T cell and B cell epitopes. Although the T cell epitope pattern can be highly diverse for individual patients, several immuno-prominent T cell epitopes have been identified. Such conserved T cell epitopes and IgE cross-reactive B cell epitopes contribute to cross-reactivity between food allergens of the same family and to clinical cross-reactivity, similar to the birch pollen-food syndrome. © 2015 S. Karger AG, Basel.

A dinucleotide motif in oligonucleotides shows potent immunomodulatory activity and overrides species-specific recognition observed with CpG motif.

PubMed

Kandimalla, Ekambar R; Bhagat, Lakshmi; Zhu, Fu-Gang; Yu, Dong; Cong, Yan-Ping; Wang, Daqing; Tang, Jimmy X; Tang, Jin-Yan; Knetter, Cathrine F; Lien, Egil; Agrawal, Sudhir

2003-11-25

Bacterial and synthetic DNAs containing CpG dinucleotides in specific sequence contexts activate the vertebrate immune system through Toll-like receptor 9 (TLR9). In the present study, we used a synthetic nucleoside with a bicyclic heterobase [1-(2'-deoxy-beta-d-ribofuranosyl)-2-oxo-7-deaza-8-methyl-purine; R] to replace the C in CpG, resulting in an RpG dinucleotide. The RpG dinucleotide was incorporated in mouse- and human-specific motifs in oligodeoxynucleotides (oligos) and 3'-3-linked oligos, referred to as immunomers. Oligos containing the RpG motif induced cytokine secretion in mouse spleen-cell cultures. Immunomers containing RpG dinucleotides showed activity in transfected-HEK293 cells stably expressing mouse TLR9, suggesting direct involvement of TLR9 in the recognition of RpG motif. In J774 macrophages, RpG motifs activated NF-kappa B and mitogen-activated protein kinase pathways. Immunomers containing the RpG dinucleotide induced high levels of IL-12 and IFN-gamma, but lower IL-6 in time- and concentration-dependent fashion in mouse spleen-cell cultures costimulated with IL-2. Importantly, immunomers containing GTRGTT and GARGTT motifs were recognized to a similar extent by both mouse and human immune systems. Additionally, both mouse- and human-specific RpG immunomers potently stimulated proliferation of peripheral blood mononuclear cells obtained from diverse vertebrate species, including monkey, pig, horse, sheep, goat, rat, and chicken. An immunomer containing GTRGTT motif prevented conalbumin-induced and ragweed allergen-induced allergic inflammation in mice. We show that a synthetic bicyclic nucleotide is recognized in the C position of a CpG dinucleotide by immune cells from diverse vertebrate species without bias for flanking sequences, suggesting a divergent nucleotide motif recognition pattern of TLR9.

Purkinje Cell Compartmentation in the Cerebellum of the Lysosomal Acid Phosphatase 2 Mutant Mouse (Nax - Naked-Ataxia Mutant Mouse)

PubMed Central

Bailey, Karen; Rahimi Balaei, Maryam; Mannan, Ashraf; Del Bigio, Marc R.; Marzban, Hassan

2014-01-01

The Acp2 gene encodes the beta subunit of lysosomal acid phosphatase, which is an isoenzyme that hydrolyzes orthophosphoric monoesters. In mice, a spontaneous mutation in Acp2 results in severe cerebellar defects. These include a reduced size, abnormal lobulation, and an apparent anterior cerebellar disorder with an absent or hypoplastic vermis. Based on differential gene expression in the cerebellum, the mouse cerebellar cortex can normally be compartmentalized anteroposteriorly into four transverse zones and mediolaterally into parasagittal stripes. In this study, immunohistochemistry was performed using various Purkinje cell compartmentation markers to examine their expression patterns in the Acp2 mutant. Despite the abnormal lobulation and anterior cerebellar defects, zebrin II and PLCβ4 showed similar expression patterns in the nax mutant and wild type cerebellum. However, fewer stripes were found in the anterior zone of the nax mutant, which could be due to a lack of Purkinje cells or altered expression of the stripe markers. HSP25 expression was uniform in the central zone of the nax mutant cerebellum at around postnatal day (P) 18–19, suggesting that HSP25 immunonegative Purkinje cells are absent or delayed in stripe pattern expression compared to the wild type. HSP25 expression became heterogeneous around P22–23, with twice the number of parasagittal stripes in the nax mutant compared to the wild type. Aside from reduced size and cortical disorganization, both the posterior zone and nodular zone in the nax mutant appeared less abnormal than the rest of the cerebellum. From these results, it is evident that the anterior zone of the nax mutant cerebellum is the most severely affected, and this extends beyond the primary fissure into the rostral central zone/vermis. This suggests that ACP2 has critical roles in the development of the anterior cerebellum and it may regulate anterior and central zone compartmentation. PMID:24722417

Current Status of Standardization of Inhalant Allergen Extracts in Korea

PubMed Central

Jeong, Kyoung Yong; Lee, Jae-Hyun; Kim, Eun-Jin; Lee, Joo-Shil; Cho, Sang-Heon; Hong, Soo-Jong

2014-01-01

Allergy diagnosis and immunotherapy in Korea rely mostly on imported allergen extracts. However, some allergens that are not important in Western countries are not commercially available, and even the same species of allergen source often displays differences in allergenicity due to amino acid sequence polymorphisms. Therefore, it is essential to prepare allergen extracts that reflect regional characteristics. Allergen standardization has been performed since 2009 with the support of the Korea Center for Disease Control and Prevention. Here, we summarize the current status of allergen standardization, focusing on the house dust mite and cockroach. Pollen allergens that are under investigation are also briefly described. PMID:24843793

Allergenically active components of cat allergen extracts.

PubMed

Anderson, M C; Baer, H

1981-09-01

The allergens involved in cat allergy have been studied in pelt extracts, saliva, serum, and urine. Using crossed immunoelectrophoresis (CIE) to examine the antigenic content, and crossed radioimmunoelectrophoresis (CRIE) and RAST to examine the allergenic content, it was found that allergen 1 of Dr. Ohman is the most important allergenic component, whereas albumin and several unidentified proteins play a minor role. Allergen 1 was not detectable in serum and urine. The allergenic and nonallergenic proteins of pelt extract and saliva were identical by CIE, suggesting that pelt extract proteins are mainly of salivary origin.

Molecular aspects of allergens in atopic dermatitis

PubMed Central

Campana, Raffaela; Dzoro, Sheron; Mittermann, Irene; Fedenko, Elena; Elisyutina, Olga; Khaitov, Musa; Karaulov, Alexander; Valenta, Rudolf

2017-01-01

Purpose of review Molecular allergology uses pure, mainly recombinant and structurally defined allergen molecules and allergen-derived epitopes to study mechanisms of IgE-associated allergy, to diagnose, and even predict the development of allergic manifestations and to treat and prevent IgE-associated allergies. Atopic dermatitis, a chronic inflammatory skin disease is almost always associated with IgE sensitization to allergens. However, also non-IgE-mediated pathomechanisms seem to be operative in atopic dermatitis and it is often difficult to identify the disease-causing allergens. Here we review recent work showing the usefulness of molecular allergology to study mechanisms of atopic dermatitis, for diagnosis and eventually for treatment and prevention of atopic dermatitis. Recent findings IgE sensitization to airborne, food-derived, microbial allergens, and autoallergens has been found to be associated with atopic dermatitis. Using defined allergen molecules and non-IgE-reactive allergen derivatives, evidence could be provided for the existence of IgE- and non-IgE-mediated mechanisms of inflammation in atopic dermatitis. Furthermore, effects of epicutaneous allergen administration on systemic allergen-specific immune responses have been studied. Multi-allergen tests containing micro-arrayed allergen molecules have been shown to be useful for the identification of culprit allergens in atopic dermatitis and may improve the management of atopic dermatitis by allergen-specific immunotherapy, allergen avoidance, and IgE-targeting therapies in a personalized medicine approach. Summary Molecular allergology allows for dissection of the pathomechanisms of atopic dermatitis, provides new forms of allergy diagnosis for identification of disease-causing allergens, and opens the door to new forms of management by allergen-specific and T cells-targeting or IgE-targeting interventions in a personalized medicine approach. PMID:28622169

Origin and Functional Prediction of Pollen Allergens in Plants1[OPEN

PubMed Central

Chen, Miaolin; Xu, Jie; Ren, Kang; Searle, Iain

2016-01-01

Pollen allergies have long been a major pandemic health problem for human. However, the evolutionary events and biological function of pollen allergens in plants remain largely unknown. Here, we report the genome-wide prediction of pollen allergens and their biological function in the dicotyledonous model plant Arabidopsis (Arabidopsis thaliana) and the monocotyledonous model plant rice (Oryza sativa). In total, 145 and 107 pollen allergens were predicted from rice and Arabidopsis, respectively. These pollen allergens are putatively involved in stress responses and metabolic processes such as cell wall metabolism during pollen development. Interestingly, these putative pollen allergen genes were derived from large gene families and became diversified during evolution. Sequence analysis across 25 plant species from green alga to angiosperms suggest that about 40% of putative pollen allergenic proteins existed in both lower and higher plants, while other allergens emerged during evolution. Although a high proportion of gene duplication has been observed among allergen-coding genes, our data show that these genes might have undergone purifying selection during evolution. We also observed that epitopes of an allergen might have a biological function, as revealed by comprehensive analysis of two known allergens, expansin and profilin. This implies a crucial role of conserved amino acid residues in both in planta biological function and allergenicity. Finally, a model explaining how pollen allergens were generated and maintained in plants is proposed. Prediction and systematic analysis of pollen allergens in model plants suggest that pollen allergens were evolved by gene duplication and then functional specification. This study provides insight into the phylogenetic and evolutionary scenario of pollen allergens that will be helpful to future characterization and epitope screening of pollen allergens. PMID:27436829

Origin and Functional Prediction of Pollen Allergens in Plants.

PubMed

Chen, Miaolin; Xu, Jie; Devis, Deborah; Shi, Jianxin; Ren, Kang; Searle, Iain; Zhang, Dabing

2016-09-01

Pollen allergies have long been a major pandemic health problem for human. However, the evolutionary events and biological function of pollen allergens in plants remain largely unknown. Here, we report the genome-wide prediction of pollen allergens and their biological function in the dicotyledonous model plant Arabidopsis (Arabidopsis thaliana) and the monocotyledonous model plant rice (Oryza sativa). In total, 145 and 107 pollen allergens were predicted from rice and Arabidopsis, respectively. These pollen allergens are putatively involved in stress responses and metabolic processes such as cell wall metabolism during pollen development. Interestingly, these putative pollen allergen genes were derived from large gene families and became diversified during evolution. Sequence analysis across 25 plant species from green alga to angiosperms suggest that about 40% of putative pollen allergenic proteins existed in both lower and higher plants, while other allergens emerged during evolution. Although a high proportion of gene duplication has been observed among allergen-coding genes, our data show that these genes might have undergone purifying selection during evolution. We also observed that epitopes of an allergen might have a biological function, as revealed by comprehensive analysis of two known allergens, expansin and profilin. This implies a crucial role of conserved amino acid residues in both in planta biological function and allergenicity. Finally, a model explaining how pollen allergens were generated and maintained in plants is proposed. Prediction and systematic analysis of pollen allergens in model plants suggest that pollen allergens were evolved by gene duplication and then functional specification. This study provides insight into the phylogenetic and evolutionary scenario of pollen allergens that will be helpful to future characterization and epitope screening of pollen allergens. © 2016 American Society of Plant Biologists. All rights reserved.

Hybridization of mouse lemurs: different patterns under different ecological conditions

PubMed Central

2011-01-01

Background Several mechanistic models aim to explain the diversification of the multitude of endemic species on Madagascar. The island's biogeographic history probably offered numerous opportunities for secondary contact and subsequent hybridization. Existing diversification models do not consider a possible role of these processes. One key question for a better understanding of their potential importance is how they are influenced by different environmental settings. Here, we characterized a contact zone between two species of mouse lemurs, Microcebus griseorufus and M. murinus, in dry spiny bush and mesic gallery forest that border each other sharply without intermediate habitats between them. We performed population genetic analyses based on mtDNA sequences and nine nuclear microsatellites and compared the results to a known hybrid zone of the same species in a nearby wide gradient from dry spiny bush over transitional forest to humid littoral forest. Results In the spiny-gallery system, Microcebus griseorufus is restricted to the spiny bush; Microcebus murinus occurs in gallery forest and locally invades the dryer habitat of its congener. We found evidence for bidirectional introgressive hybridization, which is closely linked to increased spatial overlap within the spiny bush. Within 159 individuals, we observed 18 hybrids with mitochondrial haplotypes of both species. Analyses of simulated microsatellite data indicate that we identified hybrids with great accuracy and that we probably underestimated their true number. We discuss short-term climatic fluctuations as potential trigger for the dynamic of invasion and subsequent hybridization. In the gradient hybrid zone in turn, long-term aridification could have favored unidirectional nuclear introgression from Microcebus griseorufus into M. murinus in transitional forest. Conclusions Madagascar's southeastern transitional zone harbors two very different hybrid zones of mouse lemurs in different environmental settings. This sheds light on the multitude of opportunities for the formation of hybrid zones and indicates an important influence of environmental factors on secondary contact and hybridization. Our findings suggest that hybridization could enhance the adaptability of mouse lemurs without necessarily leading to a loss of distinctiveness. They point to a potential role of hybridization in Madagascar's diversification history that requires further investigation. PMID:21989384

Allergens retained in clothing.

PubMed

Nedorost, Susan; Kessler, Margaret; McCormick, Thomas

2007-12-01

Some patients state compliance with avoidance of identified allergens, yet have persistent dermatitis in areas under tight-fitting clothing. To analyze a series of such cases to identify allergens most likely retained in clothing. Review of contact dermatitis clinic cases and identification of type and formula weight of allergens involved. High-formula-weight allergens and allergens present in medicament ointments are difficult to dissolve in laundry detergent and water and may be retained in clothing. Retention of allergens in clothing, even after washing, may explain recalcitrant dermatitis in a patient who states compliance with avoidance of a seemingly relevant allergen. Dermatologists should consider the possibility of allergen retention in clothing whenever a patient has only partial clearing after at least 1 month of attempted compliance with avoidance of identified allergens. Purchase of new clothing may be required to clear allergic contact dermatitis in this situation.

Food allergens in mattress dust in Norwegian homes - a potentially important source of allergen exposure.

PubMed

Bertelsen, R J; Faeste, C K; Granum, B; Egaas, E; London, S J; Carlsen, K-H; Lødrup Carlsen, K C; Løvik, M

2014-01-01

Sensitization to food allergens and food allergic reactions are mostly caused by ingesting the allergen, but can also occur from exposure via the respiratory tract or the skin. Little is known about exposure to food allergens in the home environment. The objective of this study was firstly to describe the frequency of detection of allergens from fish, egg, milk, and peanut in mattress dust collected from homes of 13-year-old adolescents and secondly to identify home characteristics associated with the presence of food allergen contamination in dust. Food allergens were measured by dot blot analysis in mattress dust from 143 homes in Oslo, Norway. We analysed associations between home characteristics (collected by parental questionnaires and study technicians) and food allergens by multivariate regression models. Fish allergen was detected in 46%, peanut in 41%, milk in 39%, and egg allergen in 22% of the mattress dust samples; only three samples contained none of these allergens. All four food allergens were more frequently detected in mattresses in small dwellings (< 100 m(2)) than larger dwellings (≥ 130 m(2)); 63-71% of the small dwellings (n = 24) had milk, peanut, and fish allergens in the samples compared with 33-44% of the larger dwellings (n = 95). Milk, peanut, and egg allergens were more frequently detected in homes with bedroom and kitchen on the same floor as compared with different floors, with odds ratios of 2.5 (95% confidence interval (CI): 1.1, 5.6) for milk, 2.4 (95% CI: 1.0, 6.1) for peanut, and 3.1 (95% CI: 1.3, 7.5) for egg allergens. Food allergens occurred frequently in beds in Norwegian homes, with dwelling size and proximity of kitchen and bedroom as the most important determinants. Due to the amount of time children spent in the bedroom, mattress dust may be an important source of exposure to food allergens. © 2013 John Wiley & Sons Ltd.

Food Allergens in Mattress Dust in Norwegian Homes - A Potentially Important Source of Allergen Exposure

PubMed Central

Bertelsen, Randi J.; Fæste, Christiane K.; Granum, Berit; Egaas, Eliann; London, Stephanie J.; Carlsen, Kai-Håkon; Carlsen, Karin C. Lødrup; Løvik, Martinus

2014-01-01

Background Sensitization to food allergens and food allergic reactions are mostly caused by ingesting the allergen, but can also occur from exposure via the respiratory tract or the skin. Little is known about exposure to food allergens in the home environment. Objective To describe the frequency of detection of allergens from fish, egg, milk, and peanut in mattress dust collected from homes of 13 year old adolescents, and secondly to identify home characteristics associated with the presence of food allergen contamination in dust. Methods Food allergens were measured by dot blot analysis in mattress dust from 143 homes in Oslo, Norway. We analyzed associations between home characteristics (collected by parental questionnaires and study technicians) and food allergens by multivariate regression models. Results Fish allergen was detected in 46%, peanut in 41%, milk in 39%, and egg allergen in 22% of the mattress dust samples; only three samples contained none of these allergens. All four food allergens were more frequently detected in mattresses in small dwellings (<100m2) than larger dwellings (≥130 m2); 63-71% of the small dwellings (n=24) had milk, peanut, and fish allergens in the samples compared to 33-44% of the larger dwellings (n=95). Milk, peanut, and egg allergens were more frequently detected in homes with bedroom and kitchen on the same floor as compared with different floors; with odds ratios of 2.5 (95% confidence interval (CI): 1.1, 5.6) for milk, 2.4 (95% CI: 1.0, 6.1) for peanut, and 3.1 (95% CI: 1.3, 7.5) for egg allergens. Conclusions and clinical relevance Food allergens occurred frequently in beds in Norwegian homes, with dwelling size and proximity of kitchen and bedroom as the most important determinants. Due to the amount of time children spend in the bedroom, mattress dust may be an important source of exposure to food allergens. PMID:24304208

[Sampling of allergens in dust deposited in the workplace].

PubMed

Perfetti, L; Galdi, E; Pozzi, V; Moscato, G

2001-01-01

Some workplaces share with domestic dwellings many characteristics favouring house dust mite growth. Moreover it has recently been shown that pets owners can bring allergens to public places with their clothes. So it is possible that significant exposure to indoor allergens can occur outside homes, at the workplace. The recent availability of immunoassays with monoclonal antibodies for indoor allergens has enabled many investigators to quantify exposure to such allergens in epidemiological studies. Analysis of allergens in settled dust is a simple method of quantification exposure to indoor allergens. The concentrations of indoor allergens in public places have already been investigated and high levels of indoor allergens have been reported. A study performed by our group in offices (banks and media) in different regions of Italy has also shown significant levels of indoor allergens. Thus, evaluating exposure to indoor allergens at the workplace is critical to evaluate risk factors for sensitization and elicitation of symptoms in sensitized subjects and such data help in addressing correctly the problem of reducing exposure levels.

A DNA Aptamer Recognizes the Asp f 1 Allergen of Aspergillus fumigatus

PubMed Central

Low, Swee Yang; Hill, Jane E.; Peccia, Jordan

2009-01-01

Allergies are caused by the binding of IgE antibodies onto specific sites on allergens. However, in the assessment of exposure to airborne allergens, current techniques such as whole spore counts fail to account for the presence of these allergenic epitopes that trigger allergic reactions. The objective of the research is to develop a DNA aptamer for the Asp f 1 allergen of the pathogenic fungus Aspergillus fumigatus, using an IgE-binding epitope of the allergen as the target for aptamer selection. Through in vitro SELEX, an aptamer has been produced that binds with nanomolar affinity to the Asp f 1 IgE-epitope. The aptamer is also able to recognize the native Asp f 1 allergen, and does not bind to allergenic proteins from non-target mold species such as Alternaria alternata. Production of this aptamer provides proof-of-principle that allergen measurement methods can be developed to indicate the potent fraction, or allergenicity, of allergens. PMID:19545545

Production of recombinant allergens in plants.

PubMed

Schmidt, Georg; Gadermaier, Gabriele; Pertl, Heidi; Siegert, Marc; Oksman-Caldentey, Kirsi-Marja; Ritala, Anneli; Himly, Martin; Obermeyer, Gerhard; Ferreira, Fatima

2008-10-01

A large percentage of allergenic proteins are of plant origin. Hence, plant-based expression systems are considered ideal for the recombinant production of certain allergens. First attempts to establish production of plant-derived allergens in plants focused on transient expression in Nicotiana benthamiana infected with recombinant viral vectors. Accordingly, allergens from birch and mugwort pollen, as well as from apple have been expressed in plants. Production of house dust mite allergens has been achieved by Agrobacterium-mediated transformation of tobacco plants. Beside the use of plants as production systems, other approaches have focused on the development of edible vaccines expressing allergens or epitopes thereof, which bypasses the need of allergen purification. The potential of this approach has been convincingly demonstrated for transgenic rice seeds expressing seven dominant human T cell epitopes derived from Japanese cedar pollen allergens. Parallel to efforts in developing recombinant-based diagnostic and therapeutic reagents, different gene-silencing approaches have been used to decrease the expression of allergenic proteins in allergen sources. In this way hypoallergenic ryegrass, soybean, rice, apple, and tomato were developed.

Integrating Allergen Analysis Within a Risk Assessment Framework: Approaches to Development of Targeted Mass Spectrometry Methods for Allergen Detection and Quantification in the iFAAM Project.

PubMed

Nitride, Chiara; Lee, Victoria; Baricevic-Jones, Ivona; Adel-Patient, Karine; Baumgartner, Sabine; Mills, E N Clare

2018-01-01

Allergen analysis is central to implementing and monitoring food allergen risk assessment and management processes by the food industry, but current methods for the determination of allergens in foods give highly variable results. The European Union-funded "Integrated Approaches to Food Allergen and Allergy Risk Management" (iFAAM) project has been working to address gaps in knowledge regarding food allergen management and analysis, including the development of novel MS and immuno-based allergen determination methods. Common allergenic food ingredients (peanut, hazelnut, walnut, cow's milk [Bos domesticus], and hen's egg [Gallus domesticus]) and common food matrixes (chocolate dessert and cookie) have been used for both clinical studies and analytical method development to ensure that the new methods are clinically relevant. Allergen molecules have been used as analytical targets and allergenic ingredients incurred into matrixes at levels close to reference doses that may trigger the use of precautionary allergen labeling. An interlaboratory method comparison has been undertaken for the determination of peanut in chocolate dessert using MS and immuno-based methods. The iFAAM approach has highlighted the need for methods to report test results in allergenic protein. This will allow food business operators to use them in risk assessments that are founded on clinical study data in which protein has been used as a measure of allergenic potency.

Sialylated Fetuin-A as a candidate predictive biomarker for successful grass pollen allergen immunotherapy.

PubMed

Caillot, Noémie; Bouley, Julien; Jain, Karine; Mariano, Sandrine; Luce, Sonia; Horiot, Stéphane; Airouche, Sabi; Beuraud, Chloé; Beauvallet, Christian; Devillier, Philippe; Chollet-Martin, Sylvie; Kellenberger, Christine; Mascarell, Laurent; Chabre, Henri; Batard, Thierry; Nony, Emmanuel; Lombardi, Vincent; Baron-Bodo, Véronique; Moingeon, Philippe

2017-09-01

Eligibility to immunotherapy is based on the determination of IgE reactivity to a specific allergen by means of skin prick or in vitro testing. Biomarkers predicting the likelihood of clinical improvement during immunotherapy would significantly improve patient selection. Proteins were differentially assessed by using 2-dimensional differential gel electrophoresis and label-free mass spectrometry in pretreatment sera obtained from clinical responders and nonresponders within a cohort of 82 patients with grass pollen allergy receiving sublingual immunotherapy or placebo. Functional studies of Fetuin-A (FetA) were conducted by using gene silencing in a mouse asthma model, human dendritic cell in vitro stimulation assays, and surface plasmon resonance. Analysis by using quantitative proteomics of pretreatment sera from patients with grass pollen allergy reveals that high levels of O-glycosylated sialylated FetA isoforms are found in patients exhibiting a strong decrease in rhinoconjunctivitis symptoms after sublingual immunotherapy. Although FetA is involved in numerous inflammatory conditions, its potential role in allergy is unknown. In vivo silencing of the FETUA gene in BALB/c mice results in a dramatic upregulation of airway hyperresponsiveness, lung resistance, and T H 2 responses after allergic sensitization to ovalbumin. Both sialylated and nonsialytated FetA bind to LPS, but only the former synergizes with LPS and grass pollen or mite allergens to enhance the Toll-like receptor 4-mediated proallergic properties of human dendritic cells. As a reflection of the patient's inflammatory status, pretreatment levels of sialylated FetA in the blood are indicative of the likelihood of clinical responses during grass pollen immunotherapy. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Fungal exposure, atopy, and asthma exacerbations in Puerto Rican children.

PubMed

Blatter, Joshua; Forno, Erick; Brehm, John; Acosta-Pérez, Edna; Alvarez, María; Colón-Semidey, Angel; Thorne, Peter S; Metwali, Nervana; Canino, Glorisa; Celedón, Juan C

2014-07-01

Glucan is a component of the fungal cell wall that is used as a marker of fungal exposure. Little is known about indoor glucan, atopy, and asthma exacerbations among children living in tropical environments such as Puerto Rico. Our objective was to examine whether glucan exposure is associated with degree of atopy or visits to the emergency department (ED)/urgent care for asthma in Puerto Rican children. This was a cross-sectional study of 317 children aged 6 to 14 years with (cases, n = 160) and without (control subjects, n = 157) asthma in San Juan, Puerto Rico. Our primary outcomes were the number of positive skin tests to allergens (range, 0-15) and (in cases only) having had at least one visit to the ED/urgent care for asthma in the prior year. Levels of glucan, endotoxin, peptidoglycan, and five allergens (Der p 1, Bla g 2, Fel d 1, Can f 1, and Mus m 1) were measured in samples of house dust. Linear or logistic regression was used for the multivariate analysis. In a multivariate analysis adjusting for case-control status, mouse allergen, and other covariates, children exposed to glucan levels in the second and third quartiles had approximately two more positive skin tests than those in the lowest quartile (P < 0.01 in both instances). Among children with asthma, exposure to the highest quartile of glucan was associated with nearly ninefold greater odds of one or more visits to the ED/urgent care for asthma (95% confidence interval for adjusted odds ratio, 2.7-28.4; P < 0.001). Our results suggest that indoor fungal exposure leads to an increased degree of atopy and visits to the ED/urgent care for asthma in Puerto Rican children.

Fungal Exposure, Atopy, and Asthma Exacerbations in Puerto Rican Children

PubMed Central

Blatter, Joshua; Forno, Erick; Brehm, John; Acosta-Pérez, Edna; Alvarez, María; Colón-Semidey, Angel; Thorne, Peter S.; Metwali, Nervana; Canino, Glorisa

2014-01-01

Background: Glucan is a component of the fungal cell wall that is used as a marker of fungal exposure. Little is known about indoor glucan, atopy, and asthma exacerbations among children living in tropical environments such as Puerto Rico. Our objective was to examine whether glucan exposure is associated with degree of atopy or visits to the emergency department (ED)/urgent care for asthma in Puerto Rican children. Methods: This was a cross-sectional study of 317 children aged 6 to 14 years with (cases, n = 160) and without (control subjects, n = 157) asthma in San Juan, Puerto Rico. Our primary outcomes were the number of positive skin tests to allergens (range, 0–15) and (in cases only) having had at least one visit to the ED/urgent care for asthma in the prior year. Levels of glucan, endotoxin, peptidoglycan, and five allergens (Der p 1, Bla g 2, Fel d 1, Can f 1, and Mus m 1) were measured in samples of house dust. Linear or logistic regression was used for the multivariate analysis. Measurements and Main Results: In a multivariate analysis adjusting for case-control status, mouse allergen, and other covariates, children exposed to glucan levels in the second and third quartiles had approximately two more positive skin tests than those in the lowest quartile (P < 0.01 in both instances). Among children with asthma, exposure to the highest quartile of glucan was associated with nearly ninefold greater odds of one or more visits to the ED/urgent care for asthma (95% confidence interval for adjusted odds ratio, 2.7–28.4; P < 0.001). Conclusions: Our results suggest that indoor fungal exposure leads to an increased degree of atopy and visits to the ED/urgent care for asthma in Puerto Rican children. PMID:24915164

In vivo and T cell cross-reactivity between walnut, cashew and peanut.

PubMed

Kulis, Michael; Pons, Laurent; Burks, A Wesley

2009-01-01

Examination of IgE cross-reactivity among nuts has been limited to in vitro experiments. Cross-reactivity studies of nuts at the T cell level are difficult to interpret because of the inability to determine which cellular responses are from a true sensitization and which are due to cross-reactivity. Using a mouse model in which the sensitizing nuts are controlled may provide novel methods to investigate in vivo and T cell cross-reactivity. C3H/HeJ mice were sensitized by intraperitoneal injection of cashew alone (monosensitized mice), or cashew plus walnut, utilizing alum as an adjuvant. Both groups underwent challenges to cashew, walnut and peanut, with subsequent monitoring of anaphylactic reactions. Anaphylactic antibodies were quantified by ELISA, and protein allergens were identified by Western blotting. Cellular responses were studied via splenocyte proliferation assay and measurement of secreted cytokines. The monosensitized mice reacted to cashew and walnut during challenges, with significantly weaker reactions induced on challenge with peanut. Cross-reactive IgE to walnut and peanut were detected by ELISA, and the cross-reactive allergens were identified as vicilin proteins. In cellular assays, splenocytes from the monosensitized mice proliferated and produced IL-4 and IL-5 in response to cashew, walnut and peanut. The cashew- plus walnut-sensitized mice experienced stronger clinical reactions to walnut, recognized additional walnut allergens and secreted significantly more IL-4 and IL-5 in walnut-stimulated splenocyte assays compared to the monosensitized mice. Cross-reactivity in vivo was found between cashew and walnut, while cross-reactivity among cashew, walnut and peanut was demonstrated at the T cell level. Copyright 2008 S. Karger AG, Basel.

Effect of Mouse Strain in a Model of Chemical-induced Respiratory Allergy

PubMed Central

Nishino, Risako; Fukuyama, Tomoki; Watanabe, Yuko; Kurosawa, Yoshimi; Ueda, Hideo; Kosaka, Tadashi

2014-01-01

The inhalation of many types of chemicals is a leading cause of allergic respiratory diseases, and effective protocols are needed for the detection of environmental chemical–related respiratory allergies. In our previous studies, we developed a method for detecting environmental chemical–related respiratory allergens by using a long-term sensitization–challenge protocol involving BALB/c mice. In the current study, we sought to improve our model by characterizing strain-associated differences in respiratory allergic reactions to the well-known chemical respiratory allergen glutaraldehyde (GA). According to our protocol, BALB/c, NC/Nga, C3H/HeN, C57BL/6N, and CBA/J mice were sensitized dermally with GA for 3 weeks and then challenged with intratracheal or inhaled GA at 2 weeks after the last sensitization. The day after the final challenge, all mice were euthanized, and total serum IgE levels were assayed. In addition, immunocyte counts, cytokine production, and chemokine levels in the hilar lymph nodes (LNs) and bronchoalveolar lavage fluids (BALF) were also assessed. In conclusion, BALB/c and NC/Nga mice demonstrated markedly increased IgE reactions. Inflammatory cell counts in BALF were increased in the treated groups of all strains, especially BALB/c, NC/Nga, and CBA/J strains. Cytokine levels in LNs were increased in all treated groups except for C3H/HeN and were particularly high in BALB/c and NC/Nga mice. According to our results, we suggest that BALB/c and NC/Nga are highly susceptible to respiratory allergic responses and therefore are good candidates for use in our model for detecting environmental chemical respiratory allergens. PMID:25048268

Effect of mouse strain in a model of chemical-induced respiratory allergy.

PubMed

Nishino, Risako; Fukuyama, Tomoki; Watanabe, Yuko; Kurosawa, Yoshimi; Ueda, Hideo; Kosaka, Tadashi

2014-01-01

The inhalation of many types of chemicals is a leading cause of allergic respiratory diseases, and effective protocols are needed for the detection of environmental chemical-related respiratory allergies. In our previous studies, we developed a method for detecting environmental chemical-related respiratory allergens by using a long-term sensitization-challenge protocol involving BALB/c mice. In the current study, we sought to improve our model by characterizing strain-associated differences in respiratory allergic reactions to the well-known chemical respiratory allergen glutaraldehyde (GA). According to our protocol, BALB/c, NC/Nga, C3H/HeN, C57BL/6N, and CBA/J mice were sensitized dermally with GA for 3 weeks and then challenged with intratracheal or inhaled GA at 2 weeks after the last sensitization. The day after the final challenge, all mice were euthanized, and total serum IgE levels were assayed. In addition, immunocyte counts, cytokine production, and chemokine levels in the hilar lymph nodes (LNs) and bronchoalveolar lavage fluids (BALF) were also assessed. In conclusion, BALB/c and NC/Nga mice demonstrated markedly increased IgE reactions. Inflammatory cell counts in BALF were increased in the treated groups of all strains, especially BALB/c, NC/Nga, and CBA/J strains. Cytokine levels in LNs were increased in all treated groups except for C3H/HeN and were particularly high in BALB/c and NC/Nga mice. According to our results, we suggest that BALB/c and NC/Nga are highly susceptible to respiratory allergic responses and therefore are good candidates for use in our model for detecting environmental chemical respiratory allergens.

Laboratory animals and respiratory allergies: The prevalence of allergies among laboratory animal workers and the need for prophylaxis

PubMed Central

Ferraz, Erica; Arruda, Luisa Karla de Paula; Bagatin, Ericson; Martinez, Edson Z; Cetlin, Andrea A; Simoneti, Christian S; Freitas, Amanda S; Martinez, José A B; Borges, Marcos C; Vianna, Elcio O

2013-01-01

OBJECTIVE: Subjects exposed to laboratory animals are at a heightened risk of developing respiratory and allergic diseases. These diseases can be prevented by simple measures such as the use of personal protective equipment. We report here the primary findings of the Laboratory Animals and Respiratory Allergies Study regarding the prevalence of allergic diseases among laboratory animal workers, the routine use of preventive measures in laboratories and animal facilities, and the need for prevention programs. METHODS: Animal handlers and non-animal handlers from 2 Brazilian universities (University of São Paulo and State University of Campinas) answered specific questionnaires to assess work conditions and symptoms. These subjects also underwent spirometry, a bronchial challenge test with mannitol, and skin prick tests for 11 common allergens and 5 occupational allergens (rat, mouse, guinea pig, hamster, and rabbit). RESULTS: Four hundred fifty-five animal handlers (32±10 years old [mean±SD], 209 men) and 387 non-animal handlers (33±11 years old, 121 men) were evaluated. Sensitization to occupational allergens was higher among animal handlers (16%) than non-animal handlers (3%, p<0.01). Accessibility to personal protective equipment was measured at 85% (median, considering 73 workplaces of the animal handler group). Nineteen percent of the animal handlers indicated that they wear a respirator at all times while handling animals or working in the animal room, and only 25% of the animal handlers had received an orientation about animal-induced allergies, asthma, or rhinitis. CONCLUSION: In conclusion, our data indicate that preventive programs are necessary. We suggest providing individual advice to workers associated with institutional programs to promote a safer work environment. PMID:23778494

Pseudotyped adeno-associated virus 2/9-delivered CCL11 shRNA alleviates lung inflammation in an allergen-sensitized mouse model.

PubMed

Wu, Chia-Jen; Huang, Wen-Chung; Chen, Li-Chen; Shen, Chia-Rui; Kuo, Ming-Ling

2012-11-01

Airway infiltration by eosinophils is a major characteristic of chronic asthma. CCL11 (eotaxin-1) is secreted by lung epithelial cells and functions as the major chemokine for eosinophil recruitment. Pseudotyped adeno-associated virus (AAV) 2/9, composed by the AAV2 rep and AAV9 cap genes, can efficiently target lung epithelial cells and might carry gene sequences with therapeutic potential for asthma. This study aimed to determine whether pseudotyped AAV2/9 virus carrying the small hairpin RNA targeting CCL11 and expressed by CMV/U6 promoter could reduce eosinophilia and asthmatic responses in mite allergen-sensitized mice. Mice were sensitized by intraperitoneal and challenged by intratracheal injection with recombinant Dermatophagoides pteronyssinus group 2 allergen (rDp2). AAV2/9 viral vectors were intratracheally injected three days before the first challenge. AAV2/9 sh47 virus significantly reduced airway hyperresponsiveness, airway resistance, CCL11 levels, and eosinophilia in the lungs of sensitized mice. Th2 cytokines, including interleukins (IL)-4, IL-5, and IL-10, were also significantly reduced in the bronchoalveolar lavage fluid of AAV2/9 sh47 virus-treated mice. Th2 cytokine levels were also reduced in rDp2-stimulated mediastinal lymphocytes in treated mice. However, serum levels of rDp2-specific IgG1 and IgE, as well as Th2 cytokine levels in rDp2-stimulated splenocyte culture supernatants, were comparable to the sensitized control group. The results suggest that AAV2/9 sh47 virus relieved local instead of systemic inflammatory responses. Therefore, the CMV/U6 promoter with AAV2/9 viral vector, which is preferable to target lung epithelia cells, might be applied as a novel therapeutic approach for asthma.

Pseudotyped Adeno-Associated Virus 2/9-Delivered CCL11 shRNA Alleviates Lung Inflammation in an Allergen-Sensitized Mouse Model

PubMed Central

Wu, Chia-Jen; Huang, Wen-Chung; Chen, Li-Chen; Shen, Chia-Rui

2012-01-01

Abstract Airway infiltration by eosinophils is a major characteristic of chronic asthma. CCL11 (eotaxin-1) is secreted by lung epithelial cells and functions as the major chemokine for eosinophil recruitment. Pseudotyped adeno-associated virus (AAV) 2/9, composed by the AAV2 rep and AAV9 cap genes, can efficiently target lung epithelial cells and might carry gene sequences with therapeutic potential for asthma. This study aimed to determine whether pseudotyped AAV2/9 virus carrying the small hairpin RNA targeting CCL11 and expressed by CMV/U6 promoter could reduce eosinophilia and asthmatic responses in mite allergen-sensitized mice. Mice were sensitized by intraperitoneal and challenged by intratracheal injection with recombinant Dermatophagoides pteronyssinus group 2 allergen (rDp2). AAV2/9 viral vectors were intratracheally injected three days before the first challenge. AAV2/9 sh47 virus significantly reduced airway hyperresponsiveness, airway resistance, CCL11 levels, and eosinophilia in the lungs of sensitized mice. Th2 cytokines, including interleukins (IL)-4, IL-5, and IL-10, were also significantly reduced in the bronchoalveolar lavage fluid of AAV2/9 sh47 virus-treated mice. Th2 cytokine levels were also reduced in rDp2-stimulated mediastinal lymphocytes in treated mice. However, serum levels of rDp2-specific IgG1 and IgE, as well as Th2 cytokine levels in rDp2-stimulated splenocyte culture supernatants, were comparable to the sensitized control group. The results suggest that AAV2/9 sh47 virus relieved local instead of systemic inflammatory responses. Therefore, the CMV/U6 promoter with AAV2/9 viral vector, which is preferable to target lung epithelia cells, might be applied as a novel therapeutic approach for asthma. PMID:22913580

Experimental asthma persists in IL-33 receptor knockout mice because of the emergence of thymic stromal lymphopoietin-driven IL-9+ and IL-13+ type 2 innate lymphoid cell subpopulations.

PubMed

Verma, Mukesh; Liu, Sucai; Michalec, Lidia; Sripada, Anand; Gorska, Magdalena M; Alam, Rafeul

2017-11-10

IL-33 plays an important role in the development of experimental asthma. We sought to study the role of the IL-33 receptor suppressor of tumorigenicity 2 (ST2) in the persistence of asthma in a mouse model. We studied allergen-induced experimental asthma in ST2 knockout (KO) and wild-type control mice. We measured airway hyperresponsiveness by using flexiVent; inflammatory indices by using ELISA, histology, and real-time PCR; and type 2 innate lymphoid cells (ILC2s) in lung single-cell preparations by using flow cytometry. Airway hyperresponsiveness was increased in allergen-treated ST2 KO mice and comparable with that in allergen-treated wild-type control mice. Peribronchial and perivascular inflammation and mucus production were largely similar in both groups. Persistence of experimental asthma in ST2 KO mice was associated with an increase in levels of thymic stromal lymphopoietin (TSLP), IL-9, and IL-13, but not IL-5, in bronchoalveolar lavage fluid. Expectedly, ST2 deletion caused a reduction in IL-13 + CD4 T cells, forkhead box P3-positive regulatory T cells, and IL-5 + ILC2s. Unexpectedly, ST2 deletion led to an overall increase in innate lymphoid cells (CD45 + lin - CD25 + cells) and IL-13 + ILC2s, emergence of a TSLP receptor-positive IL-9 + ILC2 population, and an increase in intraepithelial mast cell numbers in the lung. An anti-TSLP antibody abrogated airway hyperresponsiveness, inflammation, and mucus production in allergen-treated ST2 KO mice. It also caused a reduction in innate lymphoid cell, ILC2, and IL-9 + and IL-13 + ILC2 numbers in the lung. Genetic deletion of the IL-33 receptor paradoxically increases TSLP production, which stimulates the emergence of IL-9 + and IL-13 + ILC2s and mast cells and leads to development of chronic experimental asthma. An anti-TSLP antibody abrogates all pathologic features of asthma in this model. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

A study on allergen sensitivity in patients with allergic rhinitis in Bangalore, India.

PubMed

Gowda, G; Lakshmi, S; Parasuramalu, B G; Nagaraj, C; Gowda, B V C; Somashekara, K G

2014-10-01

Allergic rhinitis is the most common form of non-infectious rhinitis, affecting 500 million people worldwide, with one-fifth of those affected living in the Indian subcontinent. The skin prick test is the most valuable test for detecting offending allergens, and can be helpful for patient education, allergen avoidance and immunotherapy planning. The skin prick test was performed with 49 allergens in 486 patients who presented with symptoms of allergic rhinitis, and the allergen profile was studied. Of the 486 allergic rhinitis patients, 335 (68.93 per cent) showed allergen positivity to the skin prick test. Dust mite was the most common allergen, with positive results in 44.65 per cent of cases. The most common offending allergen in our study was the dust mite. Identification of specific allergens for a particular geographical area aids patient education and enables allergen-specific immunotherapy.

Characteristic motifs for families of allergenic proteins

PubMed Central

Ivanciuc, Ovidiu; Garcia, Tzintzuni; Torres, Miguel; Schein, Catherine H.; Braun, Werner

2008-01-01

The identification of potential allergenic proteins is usually done by scanning a database of allergenic proteins and locating known allergens with a high sequence similarity. However, there is no universally accepted cut-off value for sequence similarity to indicate potential IgE cross-reactivity. Further, overall sequence similarity may be less important than discrete areas of similarity in proteins with homologous structure. To identify such areas, we first classified all allergens and their subdomains in the Structural Database of Allergenic Proteins (SDAP, http://fermi.utmb.edu/SDAP/) to their closest protein families as defined in Pfam, and identified conserved physicochemical property motifs characteristic of each group of sequences. Allergens populate only a small subset of all known Pfam families, as all allergenic proteins in SDAP could be grouped to only 130 (of 9318 total) Pfams, and 31 families contain more than four allergens. Conserved physicochemical property motifs for the aligned sequences of the most populated Pfam families were identified with the PCPMer program suite and catalogued in the webserver Motif-Mate (http://born.utmb.edu/motifmate/summary.php). We also determined specific motifs for allergenic members of a family that could distinguish them from non-allergenic ones. These allergen specific motifs should be most useful in database searches for potential allergens. We found that sequence motifs unique to the allergens in three families (seed storage proteins, Bet v 1, and tropomyosin) overlap with known IgE epitopes, thus providing evidence that our motif based approach can be used to assess the potential allergenicity of novel proteins. PMID:18951633

Component-resolved evaluation of the content of major allergens in therapeutic extracts for specific immunotherapy of honeybee venom allergy

PubMed Central

Blank, Simon; Etzold, Stefanie; Darsow, Ulf; Schiener, Maximilian; Eberlein, Bernadette; Russkamp, Dennis; Wolf, Sara; Graessel, Anke; Biedermann, Tilo; Ollert, Markus; Schmidt-Weber, Carsten B.

2017-01-01

ABSTRACT Allergen-specific immunotherapy is the only curative treatment of honeybee venom (HBV) allergy, which is able to protect against further anaphylactic sting reactions. Recent analyses on a molecular level have demonstrated that HBV represents a complex allergen source that contains more relevant major allergens than formerly anticipated. Moreover, allergic patients show very diverse sensitization profiles with the different allergens. HBV-specific immunotherapy is conducted with HBV extracts which are derived from pure venom. The allergen content of these therapeutic extracts might differ due to natural variations of the source material or different down-stream processing strategies of the manufacturers. Since variations of the allergen content of therapeutic HBV extracts might be associated with therapeutic failure, we adressed the component-resolved allergen composition of different therapeutic grade HBV extracts which are approved for immunotherapy in numerous countries. The extracts were analyzed for their content of the major allergens Api m 1, Api m 2, Api m 3, Api m 5 and Api m 10. Using allergen-specific antibodies we were able to demonstrate the underrepresentation of relevant major allergens such as Api m 3, Api m 5 and Api m 10 in particular therapeutic extracts. Taken together, standardization of therapeutic extracts by determination of the total allergenic potency might imply the intrinsic pitfall of losing information about particular major allergens. Moreover, the variable allergen composition of different therapeutic HBV extracts might have an impact on therapy outcome and the clinical management of HBV-allergic patients with specific IgE to particular allergens. PMID:28494206

The utility of patch tests using larger screening series of allergens.

PubMed

Larkin, A; Rietschel, R L

1998-09-01

The number of patch test allergens available within the United States for routine commercial purchase is limited. Allergens chosen for inclusion in routine screening series or patch test trays vary, and the degree of information obtained from any series may or may not serve a patient's needs. Knowledge of how well the allergens chosen for inclusion in the two commercially available sources perform compared with a more expansive panel of tests can help physicians select the more appropriate tests. From 1994 to mid-1997, 554 patients were tested with allergens recommended by the North American Contact Dermatitis Group (NACDG). This included all allergens currently available from both current domestic sources, although not in the identical form used by the Thin-layer Rapid Use Epicutaneous Test (TRUE) test (Glaxo Dermatology, Research Triangle Park, NC). Another 185 patients were tested with supplemental series of allergens. The larger the series of allergens used, the more positive tests were found and the more relevant tests as well. Hermal patch test allergens identified about 55% of the information found by the NACDG series; the TRUE test allergens (but not in the TRUE test system) identified 65%. Of the 103 reactions to supplemental allergens not found by the NACDG series, 59 were relevant. Larger series of allergens can enhance accurate diagnosis of allergic contact dermatitis. No single arbitrary series of allergens can adequately survey the contemporary environment of individual patients. Selection of allergens for testing requires consideration of the patient's history and access to appropriate environmental contactants.

Production of recombinant allergens in plants

PubMed Central

2010-01-01

A large percentage of allergenic proteins are of plant origin. Hence, plant-based expression systems are considered ideal for the recombinant production of certain allergens. First attempts to establish production of plant-derived allergens in plants focused on transient expression in Nicotiana benthamiana infected with recombinant viral vectors. Accordingly, allergens from birch and mugwort pollen, as well as from apple have been expressed in plants. Production of house dust mite allergens has been achieved by Agrobacterium-mediated transformation of tobacco plants. Beside the use of plants as production systems, other approaches have focused on the development of edible vaccines expressing allergens or epitopes thereof, which bypasses the need of allergen purification. The potential of this approach has been convincingly demonstrated for transgenic rice seeds expressing seven dominant human T cell epitopes derived from Japanese cedar pollen allergens. Parallel to efforts in developing recombinant-based diagnostic and therapeutic reagents, different gene-silencing approaches have been used to decrease the expression of allergenic proteins in allergen sources. In this way hypoallergenic ryegrass, soybean, rice, apple, and tomato were developed. PMID:21258627

CD23 surface density on B cells is associated with IgE levels and determines IgE-facilitated allergen uptake, as well as activation of allergen-specific T cells.

PubMed

Selb, Regina; Eckl-Dorna, Julia; Neunkirchner, Alina; Schmetterer, Klaus; Marth, Katharina; Gamper, Jutta; Jahn-Schmid, Beatrice; Pickl, Winfried F; Valenta, Rudolf; Niederberger, Verena

2017-01-01

Increasing evidence suggests that the low-affinity receptor for IgE, CD23, plays an important role in controlling the activity of allergen-specific T cells through IgE-facilitated allergen presentation. We sought to determine the number of CD23 molecules on immune cells in allergic patients and to investigate whether the number of CD23 molecules on antigen-presenting cells is associated with IgE levels and influences allergen uptake and allergen-specific T-cell activation. Numbers of CD23 molecules on immune cells of allergic patients were quantified by using flow cytometry with QuantiBRITE beads and compared with total and allergen-specific IgE levels, as well as with allergen-induced immediate skin reactivity. Allergen uptake and allergen-specific T-cell activation in relation to CD23 surface density were determined by using flow cytometry in combination with confocal microscopy and T cells transfected with the T-cell receptor specific for the birch pollen allergen Bet v 1, respectively. Defined IgE-allergen immune complexes were formed with human monoclonal allergen-specific IgE and Bet v 1. In allergic patients the vast majority of CD23 molecules were expressed on naive IgD + B cells. The density of CD23 molecules on B cells but not the number of CD23 + cells correlated with total IgE levels (R S  = 0.53, P = .03) and allergen-induced skin reactions (R S  = 0.63, P = .008). Uptake of allergen-IgE complexes into B cells and activation of allergen-specific T cells depended on IgE binding to CD23 and were associated with CD23 surface density. Addition of monoclonal IgE to cultured PBMCs significantly (P = .04) increased CD23 expression on B cells. CD23 surface density on B cells of allergic patients is correlated with allergen-specific IgE levels and determines allergen uptake and subsequent activation of T cells. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Unintended allergens in precautionary labelled and unlabelled products pose significant risks to UK allergic consumers.

PubMed

Remington, B C; Baumert, J L; Blom, W M; Houben, G F; Taylor, S L; Kruizinga, A G

2015-07-01

Allergens in food may pose a risk to allergic consumers. While there is EU regulation for allergens present as an ingredient, this is not the case for unintended allergen presence (UAP). Food companies use precautionary allergen labels to inform allergic individuals of a potential risk from UAPs. This study investigates the risk of an allergic reaction within the milk-, wheat-, hazelnut- and peanut-allergic populations when ingesting UK foods across multiple product categories with and without precautionary allergen labelling. Allergen risk assessment using probabilistic techniques enables the estimation of the residual risk after the consumption of a product that unintentionally contains an allergen. Within this selection of UK products, the majority that tested positive for an allergen contained a concentration of allergen predicted to cause a reaction in >1% of the allergic population. The concentrations of allergens measured were greater than the VITAL(®) 2.0 action levels and would trigger precautionary allergen labelling. This was found for products both with and without precautionary allergen labelling. The results highlight the need for the food industry and regulators to adopt a transparent, risk-based approach for the communication of the risk associated with potential cross-contact that could occur in the processing facility or production chain. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Recent development in recombinant food allergen production (abstract)

USDA-ARS?s Scientific Manuscript database

Whether for understanding the properties of food allergens or for manufacturing vaccines for allergen-specific immunotherapy, well characterized pure allergens are required. This often necessitate the use of recombinant technology in obtaining food allergens due to the very low amounts of their natu...

Distinguishing allergens from non-allergenic homologues using Physical–Chemical Property (PCP) motifs

USDA-ARS?s Scientific Manuscript database

Motivation: Quantitative guidelines to distinguish allergenic proteins from related, but non-allergenic ones are urgently needed for regulatory agencies, biotech companies and physicians. Cataloguing the SDAP database has indicated that allergenic proteins populate a relatively small number of prote...

Physicochemical characterization of allergens: quantity, identity, purity, aggregation and conformation.

PubMed

Koppelman, Stef J; Luykx, Dion M A M; de Jongh, Harmen H J; Veldhuizen, Willem Jan

2009-01-01

Allergens and allergoids can be characterized by means of physicochemical methods, resulting in a description of the protein on different structural levels. Several techniques are available and their suitability depends on the composition of the particular sample. Current European legislation on allergen products demands characterization of final products in particular focusing on identity, degree of modification (for allergoids) and stability of the composition. Structural parameters of allergens may be used to investigate the stability of an allergen product. The challenge is to identify and optimize techniques that allow determination of protein structure in the context of a formulated pharmaceutical product. As the majority of the products currently marketed are formulated with aluminium hydroxide or aluminium phosphate as a depot, most of the methods and techniques used for protein characterization in solution are not applicable. An additional hurdle is that allergen products are based on natural extracts, comprising a mixture of proteins, both allergens and non-allergens, sometimes in the presence of other uncharacterized components from the raw material. This paper describes which methods are suitable for the different stages of allergen product manufacturing, and how these relate to the current regulatory requirements. Some of the techniques are demonstrated using a model allergen, cod parvalbumin, and a chemically modified form thereof. We conclude that a variety of methods is available for characterization of proteins in solution, and that a limited number of techniques appear to be suitable for modified allergens (allergoids). Adaptation of existing methods, e.g. mass spectroscopy and infrared spectroscopy may be helpful to obtain protein parameters of allergens in a formulated allergen product. By choosing a combination of techniques, including those additional to physicochemical approaches, relevant parameters of allergens in formulated allergen products can be assessed in order to achieve a well-characterized pharmaceutical product.

Socioeconomic predictors of high allergen levels in homes in the greater Boston area.

PubMed

Kitch, B T; Chew, G; Burge, H A; Muilenberg, M L; Weiss, S T; Platts-Mills, T A; O'Connor, G; Gold, D R

2000-04-01

In the United States, childhood asthma morbidity and prevalence rates are the highest in less affluent urban minority communities. More than 80% of childhood asthmatics are allergic to one or more inhalant allergens. We evaluated whether socioeconomic status was associated with a differential in the levels and types of indoor home allergens. Dust samples for an ELISA allergen assay were collected from the homes of 499 families as part of a metropolitan Boston, Massachusetts, longitudinal birth cohort study of home allergens and asthma in children with a parental history of asthma or allergy. The proportion of homes with maximum home allergen levels in the highest category was 42% for dust mite allergen (> or = 10 microg/g Der p 1 or Der f 1), 13% for cockroach allergen (> or = 2 U/g Bla g 1 or Bla g 2), 26% for cat allergen (> or = 8 microg/g Fel d 1), and 20% for dog allergen (> or = 10 microg/g Can f 1). Homes in the high-poverty area (> 20% of the population below the poverty level) were more likely to have high cockroach allergen levels than homes in the low-poverty area [51 vs. 3%; OR, 33; 95% confidence interval (CI), 12-90], but less likely to have high levels of dust mite allergen (16 vs. 53%; OR, 0.2; CI, 0.1-0.4). Lower family income, less maternal education, and race/ethnicity (black or Hispanic vs. white) were also associated with a lower risk of high dust mite levels and a greater risk of high cockroach allergen levels. Within a single U.S. metropolitan area we found marked between-community differences in the types of allergens present in the home, but not necessarily in the overall burden of allergen exposure.

Contact allergens for armpits--allergenic fragrances specified on deodorants.

PubMed

Klaschka, Ursula

2012-11-01

According to the so-called "26 allergens rule" 26 supposedly allergenic fragrances must be specified on the containers of cosmetic products if they are present above 0.001% in leave-on products and, 0.01% in rinse-off products. This declaration is meant to inform the consumers of potential risks of skin sensitizers in the products. As many consumers of deodorants suffer from allergic or irritant contact dermatitis in the axillae, the presence of allergens in deodorants deserves special attention. The objective of this study was to find answers to the following questions: Does compulsory labeling lead to omission of strong allergenic fragrances in deodorants? Is there a difference in the use patterns of strong and weak allergens? What is the quantitative exposure to fragrances by deodorants? Is the situation in Germany different from other European countries? Is there a difference between deodorants for men and for women? I tested the implementation of the "26 allergens rule" and compiled which allergenic fragrances are specified on the containers of deodorants. Three market studies were conducted in Germany in 2008, 2010 and 2011. The labels of a total number of 374 deodorants were analyzed as to whether any of the "26 allergens" were listed. The frequency of each allergen in the deodorants was compared with results from previous studies by other authors. It was found that up to 83% of the deodorants contain at least one of the "26 allergens" and that up to 30% of all products contain strong allergens above the threshold for labeling (0.001% in the product). The most frequently listed allergens are medium or weak allergens. In comparison with other authors, the frequency of the "26 allergens" in products is slightly smaller in these recent studies for the German market. There is no significant difference between deodorants for men and women, as far as the labeling of the "26 allergens" is concerned. The results show that the mandatory labeling procedure as designed in the "26 allergen rule" is not suitable to guarantee consumer safety for deodorants. As long as consumers are not informed about allergens in products in an easy to understand and transparent way, a compulsory pictogram on the container should inform them about possible risks. Copyright © 2012 Elsevier GmbH. All rights reserved.

Sensitization rates of causative allergens for dogs with atopic dermatitis: detection of canine allergen-specific IgE.

PubMed

Kang, Min-Hee; Kim, Ha-Jung; Jang, Hye-Jin; Park, Hee-Myung

2014-12-01

Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n = 101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials.

Recombinant proteins and peptides as diagnostic and therapeutic reagents for arthropod allergies.

PubMed

Ramos, John Donnie A; Valmonte, Gardette R; de Guia, Roldan M

2007-01-01

Domestic arthropods are chief sources of potent allergens that trigger sensitization and stimulate IgE-mediated allergies. Diagnosis and immunotherapy of arthropod allergies rely on the use of natural allergen extracts which are associated with low specificity and efficacy, the risk of anaphylactic reactions, and the extended period of treatment. Most of the problems associated with natural allergen extracts for allergy diagnosis and immunotherapy can be circumvented with the use of recombinant allergens and peptides. Recombinant allergens are recently developed for microarray-based multi-allergen tests which provide component-resolved diagnosis (CRD) of the patient's sensitization profile. Moreover, recombinant protein technology and peptide chemistry have been used to construct isoallergens, allergen mutants, allergoids, T and B cell peptides, hypoallergens, and mimotopes with reduced allergenicity but enhanced immunogenicity for allergen-specific immunotherapy (SIT) and vaccination. The basics of recombinant arthropod allergen technology are in place providing a lucid future for the advancement of diagnosis and immunotherapy of arthropod allergies.

Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety.

PubMed

Panda, R; Ariyarathna, H; Amnuaycheewa, P; Tetteh, A; Pramod, S N; Taylor, S L; Ballmer-Weber, B K; Goodman, R E

2013-02-01

Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop. © 2012 John Wiley & Sons A/S.

Computational allergenicity prediction of transgenic proteins expressed in genetically modified crops.

PubMed

Verma, Alok Kumar; Misra, Amita; Subash, Swarna; Das, Mukul; Dwivedi, Premendra D

2011-09-01

Development of genetically modified (GM) crops is on increase to improve food quality, increase harvest yields, and reduce the dependency on chemical pesticides. Before their release in marketplace, they should be scrutinized for their safety. Several guidelines of different regulatory agencies like ILSI, WHO Codex, OECD, and so on for allergenicity evaluation of transgenics are available and sequence homology analysis is the first test to determine the allergenic potential of inserted proteins. Therefore, to test and validate, 312 allergenic, 100 non-allergenic, and 48 inserted proteins were assessed for sequence similarity using 8-mer, 80-mer, and full FASTA search. On performing sequence homology studies, ~94% the allergenic proteins gave exact matches for 8-mer and 80-mer homology. However, 20 allergenic proteins showed non-allergenic behavior. Out of 100 non-allergenic proteins, seven qualified as allergens. None of the inserted proteins demonstrated allergenic behavior. In order to improve the predictability, proteins showing anomalous behavior were tested by Algpred and ADFS separately. Use of Algpred and ADFS softwares reduced the tendency of false prediction to a great extent (74-78%). In conclusion, routine sequence homology needs to be coupled with some other bioinformatic method like ADFS/Algpred to reduce false allergenicity prediction of novel proteins.

Enhanced sensitization and elicitation responses caused by mixtures of common fragrance allergens.

PubMed

Bonefeld, Charlotte Menné; Nielsen, Morten Milek; Rubin, Ingrid Maria Cecilia; Vennegaard, Marie Torp; Dabelsteen, Sally; Gimenéz-Arnau, Elena; Lepoittevin, Jean-Pierre; Geisler, Carsten; Johansen, Jeanne Duus

2011-12-01

Perfumes are complex mixtures composed of many fragrance ingredients, many of which are known to be only weak allergens when tested individually. It is therefore surprising that fragrance contact allergy is one of the most common forms of contact allergy. To investigate whether mixing different fragrance allergens leads to increased sensitization potency, and to examine the difference in the challenge response to one chemical in mice sensitized either with the mixture of allergens or with only the relevant allergen. CBA mice were sensitized with three different concentrations of three fragrance allergens alone or as a mixture. The sensitization and elicitation responses were measured by ear thickness plus infiltration of B and T cells and T cell proliferation in the draining lymph nodes. We found a dose-dependent sensitization response for each of the allergens. An increased response was seen when the allergens were mixed. A stronger challenge response to cinnamal was seen in mice sensitized with the allergen mixture than in mice sensitized with cinnamal alone. Our findings suggest that mixtures of allergens increase the primary response that potentiates the generation of memory T cells in response to the specific allergen. Thus, allergen mixtures enhance both induction and elicitation of contact allergy. © 2011 John Wiley & Sons A/S.

Pollen derived low molecular compounds enhance the human allergen specific immune response in vivo.

PubMed

Gilles-Stein, S; Beck, I; Chaker, A; Bas, M; McIntyre, M; Cifuentes, L; Petersen, A; Gutermuth, J; Schmidt-Weber, C; Behrendt, H; Traidl-Hoffmann, C

2016-10-01

Besides allergens, pollen release bioactive, low molecular weight compounds that modulate and stimulate allergic reactions. Clinical relevance of these substances has not been investigated to date. To elucidate the effect of a non-allergenic, low molecular weight factors from aqueous birch pollen extracts (Bet-APE < 3 kDa) on the human allergic immune response in vivo. Birch and grass pollen allergic individuals underwent skin prick testing with allergen alone, allergen plus Bet-APE < 3 kDa, or allergen plus pre-identified candidate substances from low molecular pollen fraction. Nasal allergen challenges were performed in non-atopic and pollen allergic individuals using a 3 day repeated threshold challenge battery. Subjects were either exposed to allergen alone or to allergen plus Bet-APE< 3 kDa. Local cytokine levels, nasal secretion weights, nasal congestion and symptom scores were determined. Skin prick test reactions to pollen elicited larger weals when allergens were tested together with the low molecular weight compounds from pollen. Similar results were obtained with candidate pollen-associated lipid mediators. In nasal lining fluids of allergic patients challenged with allergen plus Bet-APE < 3 kDa, IL-8 and IgE was significantly increased as compared to allergen-only challenged patients. These patients also produced increased amounts of total nasal secretion and reported more severe rhinorrhea than the allergen-only challenged group. Low molecular compounds from pollen enhance the allergen specific immune response in the skin and nose. They are therefore of potential clinical relevance in allergic patients. © 2016 John Wiley & Sons Ltd.

Economic Factors Impacting Food Allergen Management: Perspectives from the Food Industry.

PubMed

Gupta, Ruchi S; Taylor, Steve L; Baumert, Joseph L; Kao, Lauren M; Schuster, Erik; Smith, Bridget M

2017-10-01

Food allergies affect up to 8% of children in the United States and may occasionally lead to severe life-threatening reactions. Because there is currently no cure for food allergies, strict avoidance of the allergen-containing foods is the only means of preventing an allergic reaction. Consumers rely on food manufacturers to reliably track and declare the presence of food allergens in products. Over the past 10 to 20 years, the food industry has increasingly adopted allergen control approaches in its processing facilities. However, the major industry costs related to food allergen management have not been fully described. The objective of this study was to characterize the factors that contribute to the economic impact of food allergen control practices on the food industry. A focus group (n = 100) was conducted with food industry professionals to identify key areas of cost for food allergen management. A survey based on the domains identified was then developed and disseminated to a convenience sample (n = 50) of quality control food industry specialists with knowledge of their company's food allergen management practices. Nearly all companies (92%) produced food products containing one or more of the top eight allergenic foods recognized by the U.S. Food and Drug Administration or sesame seeds. Cleaning procedures, employee training, and the potential for a recall due to allergen cross-contact were most frequently rated as the important factors in food allergen management. Recalls due to food allergen cross-contact, cleaning procedures, equipment and premises design, and employee training were ranked as the greatest allergen management expenses. Although 96% of companies had a food allergen control plan in place, nearly half (42%) had at least one food allergen-related recall within the past 5 years. The industry appears to endorse a willingness to unify precautionary allergen labeling to communicate a clear message more effectively to consumers.

Bioavailability of House Dust Mite Allergens in Sublingual Allergy Tablets Is Highly Dependent on the Formulation.

PubMed

Ohashi-Doi, Katsuyo; Kito, Hirokazu; Du, Weibin; Nakazawa, Hiroshi; Ipsen, Henrik; Gudmann, Pernille; Lund, Kaare

2017-01-01

In sublingual immunotherapy (SLIT), the immune system is addressed by solubilized allergen that interacts with immunocompetent cells of the oral mucosa, the efficiency of which is governed by 2 main factors of SLIT allergen bioavailability: the allergen concentration and the mucosal contact time. Recently, 3 house dust mite (HDM) SLIT tablets were developed that differ with regard to allergen content, nominal strength (maintenance doses: 6 SQ-HDM/10,000 Japanese Allergen Units [JAU], 12 SQ-HDM/ 20,000 JAU, and 300 IR/57,000 JAU), and formulation (freeze-dried/compressed). Here, the importance of the SLIT tablet formulation for HDM major allergen bioavailability is examined. The HDM major allergen content, tablet disintegration times, and allergen release kinetics were determined. Dissolution kinetics (allergen concentration vs. time) of Der f 1, Der p 1, and Der 2 were measured. Area under the curve (AUC) was used as a surrogate parameter for allergen bioavailability. The release of HDM major allergens from the freeze-dried tablets was complete after 30 s, while only partial release was achieved with the compressed tablets, even after prolonged dissolution. At 1 min, i.e., the recommended sublingual holding time for the freeze-dried tablets, the allergen bioavailability (AUC) of the compressed 300 IR/57,000 JAU tablet was 4.7-fold (Der f 1), 10.8-fold (Der p 1), and 23.6-fold (Der 2) lower than that of the freeze-dried 12 SQ-HDM/20,000 JAU tablet and similar to (Der f 1) and 5.3-fold (Der p 1) and 12.5-fold (Der 2) lower than that of the freeze-dried 6 SQ-HDM/10,000 JAU tablet. SLIT tablet allergen bioavailability depends highly on the tablet formulation. Only the fast-dissolving freeze-dried tablets provide maximal delivery of soluble allergens and achieve allergen concentrations that reflect the nominal tablet strengths within the recommended sublingual holding time. © 2017 S. Karger AG, Basel.

Making peanut allergens indigestible: a model system for reducing or preventing an allergic reaction

USDA-ARS?s Scientific Manuscript database

Peanut allergens are not totally resistant to digestion as previously known. Creating peanut allergen conjugates that are more resistant to digestion may prevent absorption of the allergens into the bloodstream, and thereby, an allergic reaction. Peanut allergen conjugates were prepared by covalen...

The Role of Allergen Exposure and Avoidance in Asthma

PubMed Central

Baxi, Sachin N.; Phipatanakul, Wanda

2010-01-01

Allergy testing and avoidance of allergens plays an important role in asthma control. Increased allergen exposure, in genetically susceptible individuals, can lead to allergic sensitization. Continued allergen exposure can increase the risk of asthma and other allergic diseases. In a patient with persistent asthma, identification of indoor and outdoor allergens and subsequent avoidance can improve symptoms. Often times, a patient will have multiple allergies and the avoidance plan should target all positive allergens. Several studies have shown that successful allergen remediation includes a comprehensive approach including education, cleaning, physical barriers and maintaining these practices. PMID:20568555

Allergen labelling in meat, dairy and cereal products from the Serbian market

NASA Astrophysics Data System (ADS)

Spirić, D.; Nikolić, D.; Ćirić, J.; Janković, S.; Stefanović, S.; Janković, V.; Teodorović, V.

2017-09-01

Allergens in food are a great health risk, because of the ratio of severity of problems compared to small amounts of ingested allergen. Since 2014, Serbian producers and importers of food have been obliged to declare allergens from the list of Codex Alimentarius on the product packaging. Surveillance of different meat, diary, and cereal product took place in 2016, with aim of checking if the Serbian regulatory requirements for labelling of allergens in food are being fulfilled. Out of 68 different meat products, 20 were not labelled for allergens. Thirty-six labels of various dairy products were examined revealing that allergen information was included on 27 of them. Only one of eight examined cereal products did not have allergen labelling.

Allergens in veterinary medicine.

PubMed

Mueller, R S; Janda, J; Jensen-Jarolim, E; Rhyner, C; Marti, E

2016-01-01

Allergic diseases in animals are increasingly gaining importance in veterinary practice and as research models. For intradermal testing and allergen immunotherapy, a good knowledge of relevant allergens for the individual species is of great importance. Currently, the knowledge about relevant veterinary allergens is based on sensitization rates identified by intradermal testing or serum testing for allergen-specific IgE; crude extracts are the basis for most evaluations. Only a few studies provide evidence about the molecular structure of (particularly) dust mite, insect and mould allergens in dogs and horses, respectively. In those species, some major allergens differ from those in humans. This position paper summarizes the current knowledge about relevant allergens in dogs, cats and horses. © 2015 The Authors Allergy Published by John Wiley & Sons Ltd.

Monitoring of occupational and environmental aeroallergens-- EAACI Position Paper. Concerted action of the EAACI IG Occupational Allergy and Aerobiology & Air Pollution.

PubMed

Raulf, M; Buters, J; Chapman, M; Cecchi, L; de Blay, F; Doekes, G; Eduard, W; Heederik, D; Jeebhay, M F; Kespohl, S; Krop, E; Moscato, G; Pala, G; Quirce, S; Sander, I; Schlünssen, V; Sigsgaard, T; Walusiak-Skorupa, J; Wiszniewska, M; Wouters, I M; Annesi-Maesano, I

2014-10-01

Exposure to high molecular weight sensitizers of biological origin is an important risk factor for the development of asthma and rhinitis. Most of the causal allergens have been defined based on their reactivity with IgE antibodies, and in many cases, the molecular structure and function of the allergens have been established. Significant information on allergen levels that cause sensitization and allergic symptoms for several major environmental and occupational allergens has been reported. Monitoring of high molecular weight allergens and allergen carrier particles is an important part of the management of allergic respiratory diseases and requires standardized allergen assessment methods for occupational and environmental (indoor and outdoor) allergen exposure. The aim of this EAACI task force was to review the essential points for monitoring environmental and occupational allergen exposure including sampling strategies and methods, processing of dust samples, allergen analysis, and quantification. The paper includes a summary of different methods for sampling and allergen quantification, as well as their pros and cons for various exposure settings. Recommendations are being made for different exposure scenarios. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Recombinant Allergens in Structural Biology, Diagnosis, and Immunotherapy

PubMed Central

Tscheppe, Angelika; Breiteneder, Heimo

2017-01-01

The years 1988–1995 witnessed the beginning of allergen cloning and the generation of recombinant allergens, which opened up new avenues for the diagnosis and research of human allergic diseases. Most crystal and solution structures of allergens have been obtained using recombinant allergens. Structural information on allergens allows insights into their evolutionary biology, illustrates clinically observed cross-reactivities, and makes the design of hypoallergenic derivatives for allergy vaccines possible. Recombinant allergens are widely used in molecule-based allergy diagnosis such as protein microarrays or suspension arrays. Recombinant technologies have been used to produce well-characterized, noncontaminated vaccine components with known biological activities including a variety of allergen derivatives with reduced IgE reactivity. Such recombinant hypoallergens as well as wild-type recombinant allergens have been used successfully in several immunotherapy trials for more than a decade to treat birch and grass pollen allergy. As a more recent application, the development of antibody repertoires directed against conformational epitopes during immunotherapy has been monitored by recombinant allergen chimeras. Although much progress has been made, the number and quality of recombinant allergens will undoubtedly increase and keep improving our knowledge in basic scientific investigations, diagnosis, and therapy of human allergic diseases. PMID:28467993

Evaluation of home allergen sampling devices.

PubMed

Sercombe, J K; Liu-Brennan, D; Garcia, M L; Tovey, E R

2005-04-01

Simple, inexpensive methods of sampling from allergen reservoirs are necessary for large-scale studies or low-cost householder-operated allergen measurement. We tested two commercial devices: the Indoor Biotechnologies Mitest Dust Collector and the Drager Bio-Check Allergen Control; two devices of our own design: the Electrostatic Cloth Sampler (ECS) and the Press Tape Sampler (PTS); and a Vacuum Sampler as used in many allergen studies (our Reference Method). Devices were used to collect dust mite allergen samples from 16 domestic carpets. Results were examined for correlations between the sampling methods. With mite allergen concentration expressed as microg/g, the Mitest, the ECS and the PTS correlated with the Reference Method but not with each other. When mite allergen concentration was expressed as microg/m2 the Mitest and the ECS correlated with the Reference Method but the PTS did not. In the high allergen conditions of this study, the Drager Bio-Check did not relate to any methods. The Mitest Dust Collector, the ECS and the PTS show performance consistent with the Reference Method. Many techniques can be used to collect dust mite allergen samples. More investigation is needed to prove any method as superior for estimating allergen exposure.

Mite and pet allergen levels in homes of children born to allergic and nonallergic parents: the PIAMA study.

PubMed

van Strien, Rob T; Koopman, Laurens P; Kerkhof, Marjan; Spithoven, Jack; de Jongste, Johan C; Gerritsen, Jorrit; Neijens, Herman J; Aalberse, Rob C; Smit, Henriette A; Brunekreef, Bert

2002-11-01

The Prevention and Incidence of Asthma and Mite Allergy (PIAMA) study is a birth cohort study that investigates the influence of allergen exposure on the development of allergy and asthma in the first several years of life. The objectives of this study were to investigate the relationship between a family history of allergy and/or asthma and exposure of newborn children to mite and pet allergen and to study the influence of different home and occupant characteristics on mite allergen exposure. Dust was sampled from the child's mattress and the parental mattress at 3 months after birth of the index child and analyzed for mite and pet allergens. Subjects were divided in groups according to history of asthma and allergy in their parents, and allergen exposure was studied in the different groups. Cat allergen exposure was significantly lower on parental mattresses in families with allergic mothers, but dog allergen exposure was not different. Mite allergen exposure was lower on parental mattresses in families with allergic mothers. Use of mite allergen-impermeable mattress covers reduced mite allergen exposure. Some other characteristics such as age of home and mattress were also found to influence mite allergen exposure. Parental mattresses in homes of allergic mothers had lower cat and mite (but not dog) allergen loadings than mattresses in homes of nonallergic parents. Paternal (as opposed to maternal) allergy seemed to have little influence.

Food allergen extracts to diagnose food-induced allergic diseases: How they are made.

PubMed

David, Natalie A; Penumarti, Anusha; Burks, A Wesley; Slater, Jay E

2017-08-01

To review the manufacturing procedures of food allergen extracts and applicable regulatory requirements from government agencies, potential approaches to standardization, and clinical application of these products. The effects of thermal processing on allergenicity of common food allergens are also considered. A broad literature review was conducted on the natural history of food allergy, the manufacture of allergen extracts, and the allergenicity of heated food. Regulations, guidance documents, and pharmacopoeias related to food allergen extracts from the United States and Europe were also reviewed. Authoritative and peer-reviewed research articles relevant to the topic were chosen for review. Selected regulations and guidance documents are current and relevant to food allergen extracts. Preparation of a food allergen extract may require careful selection and identification of source materials, grinding, defatting, extraction, clarification, sterilization, and product testing. Although extractions for all products licensed in the United States are performed using raw source materials, many foods are not consumed in their raw form. Heating foods may change their allergenicity, and doing so before extraction may change their allergenicity and the composition of the final product. The manufacture of food allergen extracts requires many considerations to achieve the maximal quality of the final product. Allergen extracts for a select number of foods may be inconsistent between manufacturers or unreliable in a clinical setting, indicating a potential area for future improvement. Copyright © 2016 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Hybridization between mouse lemurs in an ecological transition zone in southern Madagascar.

PubMed

Gligor, M; Ganzhorn, J U; Rakotondravony, D; Ramilijaona, O R; Razafimahatratra, E; Zischler, H; Hapke, A

2009-02-01

Hybrid zones in ecotones can be useful model systems for the study of evolutionary processes that shape the distribution and discreteness of species. Such studies could be important for an improved understanding of the complex biogeography of Madagascar, which is renowned for its outstanding degree of small-scale endemism. Certain forest remnants in central Madagascar indicate that transitional corridors across the island could have connected microendemics in different forest types in the past. Evolutionary processes in such corridors are difficult to study because most of these corridors have disappeared due to deforestation in central Madagascar. We studied a hybrid zone in one of the few remaining ecotonal corridors between dry and humid forests in Madagascar, which connects two species of mouse lemurs, Microcebus griseorufus in dry spiny forest and Microcebus murinus in humid littoral forest. We sampled 162 mouse lemurs at nine sites across this boundary. Morphometric analyses revealed intermediate morphotypes of many individuals in transitional habitat. Bayesian clustering of microsatellite genotypes and assignment tests yielded evidence for a mixed ancestry of mouse lemurs in the ecotone, where we also observed significant linkage disequilibria and heterozygote deficiency. In contrast to these observations, mitochondrial haplotypes displayed a sharply delimited boundary at the eastern edge of spiny forest, which was noncoincident with the signals from microsatellite data. Among several alternative scenarios, we propose asymmetric nuclear introgression due to male-biased dispersal, divergent environmental selection, and an expansion of dry spiny forest in the course of aridification as a probable explanation of our observations.

Regulation by commensal bacteria of neurogenesis in the subventricular zone of adult mouse brain.

PubMed

Sawada, Naoki; Kotani, Takenori; Konno, Tasuku; Setiawan, Jajar; Nishigaito, Yuka; Saito, Yasuyuki; Murata, Yoji; Nibu, Ken-Ichi; Matozaki, Takashi

2018-04-15

In the mouse olfactory bulb (OB), interneurons such as granule cells and periglomerular cells are continuously replaced by adult-born neurons, which are generated in the subventricular zone (SVZ) of the brain. We have now investigated the role of commensal bacteria in regulation of such neuronal cell turnover in the adult mouse brain. Administration of mixture of antibiotics to specific pathogen-free (SPF) mice markedly attenuated the incorporation of bromodeoxyuridine (BrdU) into the SVZ cells. The treatment with antibiotics also reduced newly generated BrdU-positive neurons in the mouse OB. In addition, the incorporation of BrdU into the SVZ cells of germ-free (GF) mice was markedly reduced compared to that apparent for SPF mice. In contrast, the reduced incorporation of BrdU into the SVZ cells of GF mice was recovered by their co-housing with SPF mice, suggesting that commensal bacteria promote the incorporation of BrdU into the SVZ cells. Finally, we found that administration of ampicillin markedly attenuated the incorporation of BrdU into the SVZ cells of SPF mice. Our results thus suggest that ampicillin-sensitive commensal bacteria regulate the neurogenesis in the SVZ of adult mouse brain. Copyright © 2018 Elsevier Inc. All rights reserved.

[Possibility of exacerbation of allergy by lunar regolith].

PubMed

Horie, Masanori; Kambara, Tatsunori; Kuroda, Etsushi; Miki, Takeo; Honma, Yoshiyuki; Aoki, Shigeru; Morimoto, Yasuo

2012-09-01

Japan, U.S.A. and other foreign space agencies have plans for the construction of a lunar base and long-term stay of astronauts on the moon. The surface of the moon is covered by a thick layer of soil that includes fine particles called "lunar regolith", which is formed by meteorite impact and space weathering. Risk assessment of particulate matter on the moon is important for astronauts working in microgravity on the moon. However, there are few investigations about the biological influences of lunar regolith. Especially, there is no investigation about allergic activity to lunar regolith. The main chemical components of lunar regolith are SiO2, Al2O3, CaO, FeO, etc. Of particular interest, approximately 50% of lunar regolith consists of SiO2. There is a report that the astronauts felt hay fever-like symptoms from the inhalation of the lunar regolith. Yellow sand, whose chemical components are similar to lunar regolith, enhances allergenic reactions, suggesting the possibility that lunar regolith has an adjuvant-like activity. Although intraperitoneal administration of lunar regolith with ovalbumin to mouse did not show enhancement of allergenic reactions, further evaluation of lunar regolith's potential to exacerbate the effects of allergies is essential for development of the moon.

Mite allergoids coupled to nonoxidized mannan from Saccharomyces cerevisae efficiently target canine dendritic cells for novel allergy immunotherapy in veterinary medicine.

PubMed

Soria, Irene; Alvarez, Javier; Manzano, Ana I; López-Relaño, Juan; Cases, Bárbara; Mas-Fontao, Ana; Cañada, F Javier; Fernández-Caldas, Enrique; Casanovas, Miguel; Jiménez-Barbero, Jesús; Palomares, Oscar; Viñals-Flórez, Luis M; Subiza, José L

2017-08-01

We have recently reported that grass pollen allergoids conjugated with nonoxidized mannan of Saccharomyces cerevisae using glutaraldehyde results in a novel hypoallergenic mannan-allergen complex with improved properties for allergen vaccination. Using this approach, human dendritic cells show a better allergen uptake and cytokine profile production (higher IL-10/IL-4 ratio) for therapeutic purposes. Here we aim to address whether a similar approach can be extended to dogs using canine dendritic cells. Six healthy Spanish Greyhound dogs were used as blood donors to obtain canine dendritic cells (DC) derived from peripheral blood monocytes. Allergens from Dermatophagoides farinae mite were polymerized and conjugated with nonoxidized mannan. Nuclear magnetic resonance (NMR), gel electrophoresis (SDS-PAGE), immunoblotting and IgE-ELISA inhibition studies were conducted to evaluate the main characteristics of the allergoid obtained. Mannan-allergen conjugate and controls were assayed in vitro for canine DC uptake and production of IL-4 and IL-10. The results indicate that the conjugation of D. farinae allergens with nonoxidized mannan was feasible using glutaraldehyde. The resulting product was a polymerized structure showing a high molecular weight as detected by NMR and SDS-PAGE analysis. The mannan-allergen conjugate was hypoallergenic with a reduced reactivity with specific dog IgE. An increase in both allergen uptake and IL-10/IL-4 ratio was obtained when canine DCs were incubated with the mannan-allergen conjugate, as compared with the control allergen preparations (unmodified D. farinae allergens and oxidized mannan-allergen conjugate). We conclude that hypoallergenic D. farinae allergens coupled to nonoxidized mannan is a novel allergen preparation suitable for canine allergy immunotherapy targeting dendritic cells. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Variability of Offending Allergens of Allergic Rhinitis According to Age: Optimization of Skin Prick Test Allergens

PubMed Central

Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo

2014-01-01

Purpose This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. Methods We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. Results A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. Conclusions A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR. PMID:24404393

Variability of offending allergens of allergic rhinitis according to age: optimization of skin prick test allergens.

PubMed

Lee, Ji-Eun; Ahn, Jae-Chul; Han, Doo Hee; Kim, Dong-Young; Kim, Jung-Whun; Cho, Sang-Heon; Park, Heung-Woo; Rhee, Chae-Seo

2014-01-01

This study evaluates offending allergens in patients with allergic rhinitis (AR) according to age that establish a minimal panel for skin prick test (SPT) allergens required to identify if a patient is sensitized. We retrospectively analyzed SPT results according to age to determine the minimum test battery panel necessary to screen at least 93%-95% of AR patients. Allergic skin tests (common airborne indoor and outdoor allergens) were performed on 7,182 patients from January 2007 to June 2011. All patients were classified into 9 groups according to age; subsequently, we investigated offending allergens by age group. A total of 5,032 (70.1%) patients were found sensitized to at least one of the 55 aeroallergen extracts tested. The annual ranking of offending allergens was not significantly different from each other over the past 5 years. House dust mites (HDM) were the most prevalent allergens ranked from first to third for all 5 years. The allergens in the minimum test panel differed slightly among all age groups; in addition, the types of sensitized allergen sources were more diverse in the older versus younger age group. HDM covered a larger proportion of the sensitized allergens in the younger age group versus the older age group. Testing with 5 allergens (Dermatophagoides farinae, Tetranychus urticae, oak, mugwort and cockroach) adequately identified over 90% of the sensitized patients. A SPT with around 5-7 allergens adequately detected most of the sensitization in the majority of the age groups in Korea. However, this study suggests that physicians perform the SPT with appropriately selected allergens in each age category for the screening of AR.

Immunoproteomic tools are used to identify masked allergens: Ole e 12, an allergenic isoflavone reductase from olive (Olea europaea) pollen.

PubMed

Castro, Lourdes; Crespo, Jesús F; Rodríguez, Julia; Rodríguez, Rosalía; Villalba, Mayte

2015-12-01

Proteins performing important biochemical activities in the olive tree (Olea europaea) pollen have been identified as allergens. One novel 37-kDa protein seems to be associated to the IgE-binding profile of a group of patients suffering allergy to peach and olive pollen. Three previously described olive pollen allergens exhibit very similar molecular mass. Our objective was to identify this allergen by using immunoproteomic approaches. After 2D-electrophoresis and mass spectrometry, peptide sequences from several IgE-binding spots, allowed identifying this new allergen, as well as cloning and DNA sequencing of the corresponding gene. The allergen, named Ole e 12, is a polymorphic isoflavone reductase-like protein of 308 amino acids showing 80% and 74% identity with birch and pear allergens, Bet v 6 and Pyr c 5, respectively. A prevalence of 33% in the selected population is in contrast to 4%-10% in groups of subjects suffering from pollinosis. Recombinant allergen was produced in Escherichia coli, and deeply characterised. Immunoblotting and ELISA detection as well as inhibition experiments were performed with polyclonal antisera and allergic patients' sera. The recombinant allergen retains the IgE reactivity of its natural counterpart. Close structural and immunological relationships between members of this protein family were supported by their IgG recognition in vegetable species. In summary, Ole e 12 is a minor olive pollen allergen, which gains relevance in patients allergic to peach with olive pollinosis. Proteomic approaches used to analyse this allergen provide useful tools to identify hidden allergens, relevant for several allergic populations and thus complete allergenic panels. Copyright © 2015 Elsevier B.V. All rights reserved.

Safety of engineered allergen-specific immunotherapy vaccines

PubMed Central

Focke-Tejkl, Margarete; Valenta, Rudolf

2015-01-01

Purpose of review The purpose of the review is to summarize and comment on recent developments regarding the safety of engineered immunotherapy vaccines. Recent findings In the last 2 years, several studies were published in which allergy vaccines were developed on the basis of chemical modification of natural allergen extracts, the engineering of allergen molecules by recombinant DNA technology and synthetic peptide chemistry, allergen genes, new application routes and conjugation with immune modulatory molecules. Several studies exemplified the general applicability of hypoallergenic vaccines on the basis of recombinant fusion proteins consisting of nonallergenic allergen-derived peptides fused to allergen-unrelated carrier molecules. These vaccines are engineered to reduce both, immunoglobulin E (IgE) as well as allergen-specific T cell epitopes in the vaccines, and thus should provoke less IgE and T-cell-mediated side-effects. They are made to induce allergen-specific IgG antibodies against the IgE-binding sites of allergens with the T-cell help of the carrier molecule. Summary Several interesting examples of allergy vaccines with potentially increased safety profiles have been published. The concept of fusion proteins consisting of allergen-derived hypoallergenic peptides fused to allergen-unrelated proteins that seems to be broadly applicable for a variety of allergens appears to be of particular interest because it promises not only to reduce side-effects but also to increase efficacy and convenience of allergy vaccines. PMID:22885888

Multi-allergen Quantitation and the Impact of Thermal Treatment in Industry-Processed Baked Goods by ELISA and Liquid Chromatography-Tandem Mass Spectrometry.

PubMed

Parker, Christine H; Khuda, Sefat E; Pereira, Marion; Ross, Mark M; Fu, Tong-Jen; Fan, Xuebin; Wu, Yan; Williams, Kristina M; DeVries, Jonathan; Pulvermacher, Brian; Bedford, Binaifer; Zhang, Xi; Jackson, Lauren S

2015-12-16

Undeclared food allergens account for 30-40% of food recalls in the United States. Compliance with ingredient labeling regulations and the implementation of effective manufacturing allergen control plans require the use of reliable methods for allergen detection and quantitation in complex food products. The objectives of this work were to (1) produce industry-processed model foods incurred with egg, milk, and peanut allergens, (2) compare analytical method performance for allergen quantitation in thermally processed bakery products, and (3) determine the effects of thermal treatment on allergen detection. Control and allergen-incurred cereal bars and muffins were formulated in a pilot-scale industry processing facility. Quantitation of egg, milk, and peanut in incurred baked goods was compared at various processing stages using commercial enzyme-linked immunosorbent assay (ELISA) kits and a novel multi-allergen liquid chromatography (LC)-tandem mass spectrometry (MS/MS) multiple-reaction monitoring (MRM) method. Thermal processing was determined to negatively affect the recovery and quantitation of egg, milk, and peanut to different extents depending on the allergen, matrix, and analytical test method. The Morinaga ELISA and LC-MS/MS quantitative methods reported the highest recovery across all monitored allergens, whereas the ELISA Systems, Neogen BioKits, Neogen Veratox, and R-Biopharm ELISA Kits underperformed in the determination of allergen content of industry-processed bakery products.

Climate Change and Our Environment: The Effect on Respiratory and Allergic Disease

PubMed Central

Barnes, Charles S.; Alexis, Neil E.; Bernstein, Jonathan A.; Cohn, John R.; Demain, Jeffrey G.; Horner, Elliott; Levetin, Estelle; Nel, Andre; Phipatanakul, Wanda

2013-01-01

Climate change is a constant and ongoing process. It is postulated that human activities have reached a point at which we are producing global climate change. This article provides suggestions to help the allergist/environmental physician integrate recommendations about improvements in outdoor and indoor air quality and the likely response to predicted alterations in the earth’s environment into their patient’s treatment plan. Many changes that affect respiratory disease are anticipated. Examples of responses to climate change include energy reduction retrofits in homes that could potentially affect exposure to allergens and irritants, more hot sunny days that increase ozone-related difficulties, and rises in sea level or altered rainfall patterns that increase exposure to damp indoor environments. Climate changes can also affect ecosystems, manifested as the appearance of stinging and biting arthropods in new areas. Higher ambient carbon dioxide concentrations, warmer temperatures, and changes in floristic zones could potentially increase exposure to ragweed and other outdoor allergens, whereas green practices such as composting can increase allergen and irritant exposure. Finally, increased energy costs may result in urban crowding and human source pollution, leading to changes in patterns of infectious respiratory illnesses. Improved governmental controls on airborne pollutants could lead to cleaner air and reduced respiratory diseases but will meet strong opposition because of their effect on business productivity. The allergy community must therefore adapt, as physician and research scientists always have, by anticipating the needs of patients and by adopting practices and research methods to meet changing environmental conditions. PMID:23687635

Using magnetic beads to reduce reanut allergens from peanut extracts.

USDA-ARS?s Scientific Manuscript database

Ferric irons (Fe3+) and phenolic compounds have been shown to bind to peanut allergens. An easy way to isolate peanut allergens is by use of magnetic beads attached with or without phenolics to capture peanut allergens or allergen-Fe3+ complexes, thus, achieving the goal of producing peanut extracts...

COMPARISON OF SUBCUTANEOUS AND ORAL ROUTES OF EXPOSURE FOR EVALUATING ALLERGENICITY OF FOOD EXTRACTS

EPA Science Inventory

Evaluation of the potential for food allergenicity of any given protein is limited by the lack of an appropriate animal model. In this study we examined the intrinsic allergenicity of foods known to be allergenic (peanut, egg) or non-allergenic (spinach) by exposing mice either s...

Quality requirements for allergen extracts and allergoids for allergen immunotherapy.

PubMed

Zimmer, J; Bonertz, A; Vieths, S

2017-12-01

All allergen products for allergen immunotherapy currently marketed in the European Union are pharmaceutical preparations derived from allergen-containing source materials like pollens, mites and moulds. Especially this natural origin results in particular demands for the regulatory requirements governing allergen products. Furthermore, the development of regulatory requirements is complicated by the so far missing universal link between certain quality parameters, in particular biological potency, on the one hand and clinical efficacy on the other hand. As a consequence, each allergen product for specific immunotherapy has to be assessed individually for its quality, safety and efficacy. At the same time, biological potency of allergen products is most commonly determined using IgE inhibition assays based on human sera relative to product-specific in house references, ruling out full comparability of products from different manufacturers. This review article aims to summarize the current quality requirements for allergen products including the special requirements implemented for control of chemically modified allergen extracts (allergoids). Copyright © 2017 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.

Sensitization rates of causative allergens for dogs with atopic dermatitis: detection of canine allergen-specific IgE

PubMed Central

Kang, Min-Hee; Kim, Ha-Jung; Jang, Hye-Jin

2014-01-01

Allergen-specific IgE serology tests became commercially available in the 1980s. Since then these tests have been widely used to diagnose and treat allergic skin diseases. However, the relationship between a positive reaction and disease occurrence has been controversial. The purpose of this study was to evaluate allergens using a serologic allergy test in dogs with atopic dermatitis (AD). Dogs clinically diagnosed with AD (n=101) were tested using an allergen-specific IgE immunoassay. Among the total 92 environmental and food allergens, house dust and house dust mites were the most common. Several allergens including airborne pollens and molds produced positive reactions, and which was considered increasing allergens relating to the climate changes. The presence of antibodies against staphylococci and Malassezia in cases of canine AD was warranted in this study. Additionally, strong (chicken, turkey, brown rice, brewer's yeast, and soybean) and weakly (rabbit, vension, duck, and tuna) positive reactions to food allergens could be used for avoidance and limited-allergen trials. PMID:24962408

Diagnosis of Allergy to Mammals and Fish: Cross-Reactive vs. Specific Markers.

PubMed

Hilger, Christiane; van Hage, Marianne; Kuehn, Annette

2017-08-22

Allergen extracts are still widely used in allergy diagnosis as they are regarded as sensitive screening tools despite the fact that they may lack some minor allergens. Another drawback of extracts is their low specificity, which is due to the presence of cross-reactive allergens. Progress in allergen identification has disclosed a number of allergenic molecules of homologous sequence and structure which are present in different animal species. This review summarizes recent advances in mammalian and fish allergen identification and focuses on their clinical relevance. Serum albumins and parvalbumins are well-known animal panallergens. More recently several members of the lipocalin family were found to be cross-reactive between furry animals whereas in fish, additional allergens, enolase, aldolase and collagen, were found to be important and cross-reactive allergens. New epidemiological studies have analysed the prevalence and clinical relevance of mammalian and fish components. Primary sensitization can be distinguished from cross-sensitization by using marker allergens. Although substantial progress has been made in allergen identification, only few markers are commercially available for routine clinical practice.

Btk Inhibitor RN983 Delivered by Dry Powder Nose-only Aerosol Inhalation Inhibits Bronchoconstriction and Pulmonary Inflammation in the Ovalbumin Allergic Mouse Model of Asthma.

PubMed

Phillips, Jonathan E; Renteria, Lorena; Burns, Lisa; Harris, Paul; Peng, Ruoqi; Bauer, Carla M T; Laine, Dramane; Stevenson, Christopher S

2016-06-01

In allergen-induced asthma, activated mast cells start the lung inflammatory process with degranulation, cytokine synthesis, and mediator release. Bruton's tyrosine kinase (Btk) activity is required for the mast cell activation during IgE-mediated secretion. This study characterized a novel inhaled Btk inhibitor RN983 in vitro and in ovalbumin allergic mouse models of the early (EAR) and late (LAR) asthmatic response. RN983 potently, selectively, and reversibly inhibited the Btk enzyme. RN983 displayed functional activities in human cell-based assays in multiple cell types, inhibiting IgG production in B-cells with an IC50 of 2.5 ± 0.7 nM and PGD2 production from mast cells with an IC50 of 8.3 ± 1.1 nM. RN983 displayed similar functional activities in the allergic mouse model of asthma when delivered as a dry powder aerosol by nose-only inhalation. RN983 was less potent at inhibiting bronchoconstriction (IC50(RN983) = 59 μg/kg) than the β-agonist salbutamol (IC50(salbutamol) = 15 μg/kg) in the mouse model of the EAR. RN983 was more potent at inhibiting the antigen induced increase in pulmonary inflammation (IC50(RN983) = <3 μg/kg) than the inhaled corticosteroid budesonide (IC50(budesonide) = 27 μg/kg) in the mouse model of the LAR. Inhalation of aerosolized RN983 may be effective as a stand-alone asthma therapy or used in combination with inhaled steroids and β-agonists in severe asthmatics due to its potent inhibition of mast cell activation.

Btk Inhibitor RN983 Delivered by Dry Powder Nose-only Aerosol Inhalation Inhibits Bronchoconstriction and Pulmonary Inflammation in the Ovalbumin Allergic Mouse Model of Asthma

PubMed Central

Renteria, Lorena; Burns, Lisa; Harris, Paul; Peng, Ruoqi; Bauer, Carla M.T.; Laine, Dramane; Stevenson, Christopher S.

2016-01-01

Abstract Background: In allergen-induced asthma, activated mast cells start the lung inflammatory process with degranulation, cytokine synthesis, and mediator release. Bruton's tyrosine kinase (Btk) activity is required for the mast cell activation during IgE-mediated secretion. Methods: This study characterized a novel inhaled Btk inhibitor RN983 in vitro and in ovalbumin allergic mouse models of the early (EAR) and late (LAR) asthmatic response. Results: RN983 potently, selectively, and reversibly inhibited the Btk enzyme. RN983 displayed functional activities in human cell-based assays in multiple cell types, inhibiting IgG production in B-cells with an IC50 of 2.5 ± 0.7 nM and PGD2 production from mast cells with an IC50 of 8.3 ± 1.1 nM. RN983 displayed similar functional activities in the allergic mouse model of asthma when delivered as a dry powder aerosol by nose-only inhalation. RN983 was less potent at inhibiting bronchoconstriction (IC50(RN983) = 59 μg/kg) than the β-agonist salbutamol (IC50(salbutamol) = 15 μg/kg) in the mouse model of the EAR. RN983 was more potent at inhibiting the antigen induced increase in pulmonary inflammation (IC50(RN983) = <3 μg/kg) than the inhaled corticosteroid budesonide (IC50(budesonide) = 27 μg/kg) in the mouse model of the LAR. Conclusions: Inhalation of aerosolized RN983 may be effective as a stand-alone asthma therapy or used in combination with inhaled steroids and β-agonists in severe asthmatics due to its potent inhibition of mast cell activation. PMID:27111445

High-resolution crystal structure and IgE recognition of the major grass pollen allergen Phl p 3.

PubMed

Devanaboyina, S C; Cornelius, C; Lupinek, C; Fauland, K; Dall'Antonia, F; Nandy, A; Hagen, S; Flicker, S; Valenta, R; Keller, W

2014-12-01

Group 2 and 3 grass pollen allergens are major allergens with high allergenic activity and exhibit structural similarity with the C-terminal portion of major group 1 allergens. In this study, we aimed to determine the crystal structure of timothy grass pollen allergen, Phl p 3, and to study its IgE recognition and cross-reactivity with group 2 and group 1 allergens. The three-dimensional structure of Phl p 3 was solved by X-ray crystallography and compared with the structures of group 1 and 2 grass pollen allergens. Cross-reactivity was studied using a human monoclonal antibody which inhibits allergic patients' IgE binding and by IgE inhibition experiments with patients' sera. Conformational Phl p 3 IgE epitopes were predicted with the algorithm SPADE, and Phl p 3 variants containing single point mutations in the predicted IgE binding sites were produced to analyze allergic patients' IgE binding. Phl p 3 is a globular β-sandwich protein showing structural similarity to Phl p 2 and the Phl p 1-C-terminal domain. Phl p 3 showed IgE cross-reactivity with group 2 allergens but not with group 1 allergens. SPADE identified two conformational IgE epitope-containing areas, of which one overlaps with the epitope defined by the monoclonal antibody. The mutation of arginine 68 to alanine completely abolished binding of the blocking antibody. This mutation and a mutation of D13 in the predicted second IgE epitope area also reduced allergic patients' IgE binding. Group 3 and group 2 grass pollen allergens are cross-reactive allergens containing conformational IgE epitopes. They lack relevant IgE cross-reactivity with group 1 allergens and therefore need to be included in diagnostic tests and allergen-specific treatments in addition to group 1 allergens. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Determination of allergen specificity by heavy chains in grass pollen allergen-specific IgE antibodies.

PubMed

Gadermaier, Elisabeth; Flicker, Sabine; Lupinek, Christian; Steinberger, Peter; Valenta, Rudolf

2013-04-01

Affinity and clonality of allergen-specific IgE antibodies are important determinants for the magnitude of IgE-mediated allergic inflammation. We sought to analyze the contribution of heavy and light chains of human allergen-specific IgE antibodies for allergen specificity and to test whether promiscuous pairing of heavy and light chains with different allergen specificity allows binding and might affect affinity. Ten IgE Fabs specific for 3 non-cross-reactive major timothy grass pollen allergens (Phl p 1, Phl p 2, and Phl p 5) obtained by means of combinatorial cloning from patients with grass pollen allergy were used to construct stable recombinant single chain variable fragments (ScFvs) representing the original Fabs and shuffled ScFvs in which heavy chains were recombined with light chains from IgE Fabs with specificity for other allergens by using the pCANTAB 5 E expression system. Possible ancestor genes for the heavy chain and light chain variable region-encoding genes were determined by using sequence comparison with the ImMunoGeneTics database, and their chromosomal locations were determined. Recombinant ScFvs were tested for allergen specificity and epitope recognition by means of direct and sandwich ELISA, and affinity by using surface plasmon resonance experiments. The shuffling experiments demonstrate that promiscuous pairing of heavy and light chains is possible and maintains allergen specificity, which is mainly determined by the heavy chains. ScFvs consisting of different heavy and light chains exhibited different affinities and even epitope specificity for the corresponding allergen. Our results indicate that allergen specificity of allergen-specific IgE is mainly determined by the heavy chains. Different heavy and light chain pairings in allergen-specific IgE antibodies affect affinity and epitope specificity and thus might influence clinical reactivity to allergens. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

Molecular allergy diagnostics using IgE singleplex determinations: methodological and practical considerations for use in clinical routine: Part 18 of the Series Molecular Allergology.

PubMed

Kleine-Tebbe, Jörg; Jakob, Thilo

Allergen molecules (synonyms: single allergens, allergen components) open up new horizons for the targeted allergen-specific diagnostics of immunoglobulin E (IgE) in singleplex determination. The following rationales support the targeted use of allergen molecules and, more importantly, improve test properties: (1) increased test sensitivity ("analytical sensitivity"), particularly when important allergens are under-represented or lacking in the extract; (2) improved test selectivity (analytical specificity), particularly when the selected IgE repertoire against an allergen yields additional information on: (a) potential risk, (b) possible cross-reactivity, or (c) primary (species-specific) sensitization. However, the appropriate indication for the use of single allergens can only be established on a case-by-case basis (depending on the clinical context and previous history) and in an allergen-specific manner (depending on the allergen source and the single allergens available), rather than in a standardized way. Numerous investigations on suspected food allergy, insect venom allergy, or sensitization to respiratory allergens have meanwhile demonstrated the successful use of defined molecules for allergen-specific singleplex IgE diagnosis. Specific IgE to single allergens is limited in its suitability to predict the clinical relevance of sensitivity on an individual basis. In food allergies, one can at best identify the relative risk of a clinical reaction on the basis of an IgE profile, but no absolutely reliable prediction on (future) tolerance can be made. Ultimately, the clinical relevance of all IgE findings depends on the presence of corresponding symptoms and can only be assessed on an individual basis (previous history, symptom log, and provocation testing with the relevant allergen source where appropriate). Thus, also in molecular allergology, the treating physician and not the test result should determine the clinical relevance of diagnostic findings. Supplementary material is available for this article at 10.1007/s40629-015-0067-z and is accessible for authorized users.

Factors influencing the quality of Myrmecia pilosula (Jack Jumper) ant venom for use in in vitro and in vivo diagnoses of allergen sensitization and in allergen immunotherapy.

PubMed

Wanandy, T; Dwyer, H E; McLean, L; Davies, N W; Nichols, D; Gueven, N; Brown, S G A; Wiese, M D

2017-11-01

Allergen immunotherapy uses pharmaceutical preparations derived from naturally occurring source materials, which contain water-soluble allergenic components responsible for allergic reactions. The success of in vivo and in vitro diagnoses in allergen sensitization and allergen immunotherapy largely depends on the quality, composition and uniformity of allergenic materials used to produce the active ingredients, and the formulation employed to prepare finished products. We aimed to examine the factors influencing batch-to-batch consistency of Jack Jumper (Myrmecia pilosula) ant venom (JJAV) in the form of active pharmaceutical ingredient (AI) and informed whether factors such as temperature, artificial light and container materials influence the quality of JJAV AIs. We also aimed to establish handling and storage requirements of JJAV AIs to ensure preservation of allergenic activities during usage in the diagnosis of allergen sensitization and in allergen immunotherapy. The quality and consistency of JJAV AIs were analysed using a combination of bicinchoninic acid assay for total protein quantification, HPLC-UV for JJAV allergen peptides quantification, ELISA inhibition for total allergenic potency, SDS-PAGE, AU-PAGE and immunoblot for qualitative assessment of JJAV components, and Limulus Amebocyte Lysate assay for the quantification of endotoxin concentration. API-ZYM and Zymogram assays were used to probe the presence of enzymatic activities in JJAV. Pharmaceutical-grade JJAV for allergen immunotherapy has good batch-to-batch consistency. Temporary storage at 4°C and light exposure do not affect the quality of JJAV. Exposure to temperature above 40°C degrades high MW allergens in JJAV. Vials containing JJAV must be stored frozen and in upright position during long-term storage. We have identified factors, which can influence the quality and consistency of JJAV AIs, and provided a framework for appropriate handling, transporting and storage of JJAV to be used for the diagnosis of allergen sensitization and in AIT. © 2017 John Wiley & Sons Ltd.

Genetically modified soybeans and food allergies.

PubMed

Herman, Eliot M

2003-05-01

Allergenic reactions to proteins expressed in GM crops has been one of the prominent concerns among biotechnology critics and a concern of regulatory agencies. Soybeans like many plants have intrinsic allergens that present problems for sensitive people. Current GM crops, including soybean, have not been shown to add any additional allergenic risk beyond the intrinsic risks already present. Biotechnology can be used to characterize and eliminate allergens naturally present in crops. Biotechnology has been used to remove a major allergen in soybean demonstrating that genetic modification can be used to reduce allergenicity of food and feed. This provides a model for further use of GM approaches to eliminate allergens.

Structural and functional localization of airway effects from episodic exposure of infant monkeys to allergen and/or ozone

DOE Office of Scientific and Technical Information (OSTI.GOV)

Joad, Jesse P.; Kott, Kayleen S.; Bric, John M.

2006-08-01

Both allergen and ozone exposure increase asthma symptoms and airway responsiveness in children. Little is known about how these inhalants may differentially modify airway responsiveness in large proximal as compared to small distal airways. We evaluated whether bronchi and respiratory bronchioles from infant monkeys exposed episodically to allergen and/or ozone differentially develop intrinsic hyperresponsiveness to methacholine and whether eosinophils and/or pulmonary neuroendocrine cells play a role. Infant monkeys were exposed episodically for 5 months to: (1) filtered air, (2) aerosolized house dust mite allergen, (3) ozone 0.5 ppm, or (4) house dust mite allergen + ozone. Studying the function/structure relationshipmore » of the same lung slices, we evaluated methacholine airway responsiveness and histology of bronchi and respiratory bronchioles. In bronchi, intrinsic responsiveness was increased by allergen exposure, an effect reduced by bombesin antagonist. In respiratory bronchioles, intrinsic airway responsiveness was increased by allergen + ozone exposure. Eosinophils were increased by allergen and allergen + ozone exposure in bronchi and by allergen exposure in respiratory bronchioles. In both airways, exposure to allergen + ozone resulted in fewer tissue eosinophils than did allergen exposure alone. In bronchi, but not in respiratory bronchioles, the number of eosinophils and neuroendocrine cells correlated with airway responsiveness. We conclude that episodically exposing infant monkeys to house dust mite allergen with or without ozone increased intrinsic airway responsiveness to methacholine in bronchi differently than in respiratory bronchioles. In bronchi, eosinophils and neuroendocrine cells may play a role in the development of airway hyperresponsiveness.« less

Cleaning and other control and validation strategies to prevent allergen cross-contact in food-processing operations.

PubMed

Jackson, Lauren S; Al-Taher, Fadwa M; Moorman, Mark; DeVries, Jonathan W; Tippett, Roger; Swanson, Katherine M J; Fu, Tong-Jen; Salter, Robert; Dunaif, George; Estes, Susan; Albillos, Silvia; Gendel, Steven M

2008-02-01

Food allergies affect an estimated 10 to 12 million people in the United States. Some of these individuals can develop life-threatening allergic reactions when exposed to allergenic proteins. At present, the only successful method to manage food allergies is to avoid foods containing allergens. Consumers with food allergies rely on food labels to disclose the presence of allergenic ingredients. However, undeclared allergens can be inadvertently introduced into a food via cross-contact during manufacturing. Although allergen removal through cleaning of shared equipment or processing lines has been identified as one of the critical points for effective allergen control, there is little published information on the effectiveness of cleaning procedures for removing allergenic materials from processing equipment. There also is no consensus on how to validate or verify the efficacy of cleaning procedures. The objectives of this review were (i) to study the incidence and cause of allergen cross-contact, (ii) to assess the science upon which the cleaning of food contact surfaces is based, (iii) to identify best practices for cleaning allergenic foods from food contact surfaces in wet and dry manufacturing environments, and (iv) to present best practices for validating and verifying the efficacy of allergen cleaning protocols.

Indoor environmental quality in a 'low allergen' school and three standard primary schools in Western Australia.

PubMed

Zhang, G; Spickett, J; Rumchev, K; Lee, A H; Stick, S

2006-02-01

To investigate indoor environmental quality in classrooms, assessments were undertaken in a 'low allergen' school and three standard primary schools in Western Australia. Dust allergens, air pollutants and physical parameters were monitored in the four schools at four times (summer school term, autumn holiday, winter school term and winter holiday) in 2002. The levels of particulate matter (PM(10)) and volatile organic compounds were similar between the four primary schools. Although slightly decreased levels of dust-mite and cat allergens were observed in the 'low allergen' school, the reductions were not statistically significant and the allergen levels in all schools were much lower than the recommended sensitizing thresholds. However, significantly lower levels of relative humidity and formaldehyde level during summer-term were recorded in the 'low allergen' school. In conclusion, the evidence here suggests that the 'low allergen' school did not significantly improve the indoor environmental quality in classrooms. Practical Implications School is an important environment for children in terms of exposure to pollutants and allergens. By assessing the levels of key pollutants and allergens in a low allergen school and three standard primary schools in Western Australia, this study provides useful information for implementation of healthy building design that can improve the indoor environment in schools.

Known Allergen Structures Predict Schistosoma mansoni IgE-Binding Antigens in Human Infection

PubMed Central

Farnell, Edward J.; Tyagi, Nidhi; Ryan, Stephanie; Chalmers, Iain W.; Pinot de Moira, Angela; Jones, Frances M.; Wawrzyniak, Jakub; Fitzsimmons, Colin M.; Tukahebwa, Edridah M.; Furnham, Nicholas; Maizels, Rick M.; Dunne, David W.

2015-01-01

The IgE response has been associated with both allergic reactions and immunity to metazoan parasites. Recently, we hypothesized that all environmental allergens bear structural homology to IgE-binding antigens from metazoan parasites and that this homology defines the relatively small number of protein families containing allergenic targets. In this study, known allergen structures (Pfam domains) from major environmental allergen families were used to predict allergen-like (SmProfilin, SmVAL-6, SmLipocalin, SmHSP20, Sm triosephosphate isomerase, SmThioredoxin, Sm superoxide dismutase, SmCyclophilin, and Sm phosphoglycerate kinase) and non-allergen-like [Sm dynein light chain (SmDLC), SmAldolase SmAK, SmUbiquitin, and Sm14-3-3] proteins in Schistosoma mansoni. Recombinant antigens were produced in Escherichia coli and IgG1, IgG4, and IgE responses against them measured in a cohort of people (n = 222) infected with S. mansoni. All allergen-like antigens were targeted by IgE responses in infected subjects, whilst IgE responses to the non-allergen-like antigens, SmAK, SmUbiquitin, and Sm14-3-3 were essentially absent being of both low prevalence and magnitude. Two new IgE-binding Pfam domain families, not previously described in allergen family databases, were also found, with prevalent IgE responses against SmDLC (PF01221) and SmAldolase (PF00274). Finally, it was demonstrated that immunoregulatory serological processes typically associated with allergens also occurred in responses to allergen-like proteins in S. mansoni infections, including the production of IgG4 in people responding with IgE and the down-regulation of IgE in response to increased antigen exposure from S. mansoni eggs. This study establishes that structures of known allergens can be used to predict IgE responses against homologous parasite allergen-like molecules (parallergens) and that serological responses with IgE/IgG4 to parallergens mirror those seen against allergens, supporting our hypothesis that allergenicity is rooted in expression of certain protein domain families in metazoan parasites. PMID:25691884

Investigating cockroach allergens: aiming to improve diagnosis and treatment of cockroach allergic patients

PubMed Central

Pomés, Anna; Arruda, L. Karla

2013-01-01

Cockroach allergy is an important health problem associated with the development of asthma, as a consequence of chronic exposure to low levels of allergens in susceptible individuals. In the last 20 years, progress in understanding the disease has been possible, thanks to the identification and molecular cloning of cockroach allergens and their expression as recombinant proteins. Assays for assessment of environmental allergen exposure have been developed and used to measure Bla g 1 and Bla g 2, as markers of cockroach exposure. IgE antibodies to cockroach extracts and to specific purified allergens have been measured to assess sensitization and analyze association with exposure and disease. With the development of the field of structural biology and the expression of recombinant cockroach allergens, insights into allergen structure, function, epitope mapping and allergen-antibody interactions have provided further understanding of mechanisms of cockroach allergic disease at the molecular level. This information will contribute to develop new approaches to allergen avoidance and to improve diagnosis and therapy of cockroach allergy. PMID:23916425

[New allergens and pediatric allergology].

PubMed

Eng, P A

1998-09-30

The first manifestation of allergies most often occurs in childhood. Prevention of atopic diseases is one of the very important tasks in pediatrics. Exact knowledge of allergens and the role of adjuvant factors in allergic sensitisation is necessary to define measures for allergy prevention aiming at a reduction of the worldwide increasing prevalence of atopic diseases. Indoor allergens and tobacco smoke exposure are risk factors for early sensitisation and asthma. In addition to house dust mites there are other indoor allergens like moulds, pet allergens, cockroaches and many more. Exact diagnosis and identification of the causative allergen allows therapy directing towards allergen avoidance and relieving symptoms without need of any additional pharmaceutical treatment. This cost-saving strategy helps to prevent disease-related long absences from school and work. Exact knowledge of the structure and biology of the etiologic allergens is a prerequisite for this treatment strategy. We review the great contribution of the Allergy Unit in Zurich to the identification and characterisation of environmental allergens.

Effects of daily food processing on allergenicity.

PubMed

Cabanillas, Beatriz; Novak, Natalija

2017-08-11

Daily food processing has the potential to alter the allergenicity of foods due to modification of the physico-chemical properties of proteins. The degree of such modifications depends on factors such as processing conditions, type of food considered, allergenic content, etc. The impact of daily food processing like boiling, roasting, frying or baking on food allergenicity have been extensively studied. The influence of other thermal treatments such as microwave heating or pressure cooking on allergenicity has also been analyzed. Non-thermal treatment such as peeling impacts on the allergenic content of certain foods such as fruits. In this review, we give an updated overview of the effects of daily processing treatments on the allergenicity of a wide variety of foods. The different variables that contribute to the modification of food allergenicity due to processing are also reviewed and discussed.

Analysis of U.S. Food and Drug Administration food allergen recalls after implementation of the food allergen labeling and consumer protection act.

PubMed

Gendel, Steven M; Zhu, Jianmei

2013-11-01

To avoid potentially life-threatening reactions, food allergic consumers rely on information on food labels to help them avoid exposure to a food or ingredient that could trigger a reaction. To help consumers in the United States obtain the information that they need, the Food Allergen Labeling and Consumer Protection Act of 2004 defined a major food allergen as being one of eight foods or food groups and any ingredient that contains protein from one of these foods or food groups. A food that contains an undeclared major food allergen is misbranded under the U.S. Food, Drug, and Cosmetic Act and is subject to recall. Food allergen labeling problems are the most common cause of recalls for U.S. Food and Drug Administration (FDA)-regulated food products. To help understand why food allergen recalls continue to occur at a high rate, information on each food allergen recall that occurred in fiscal years 2007 through 2012 was obtained from the FDA recall database. This information was analyzed to identify the food, allergen, root cause, and mode of discovery for each food allergen recall. Bakery products were the most frequently recalled food type, and milk was the most frequently undeclared major food allergen. Use of the wrong package or label was the most frequent problem leading to food allergen recalls. These data are the first reported that indicate the importance of label and package controls as public health measures.

Natural rubber latex allergens: new developments.

PubMed

Yeang, Hoong-Yeet

2004-04-01

New allergenic latex proteins have been identified, whereas further information on known latex allergens has emerged in recent years. Although prevalence figures for sensitization to the various latex allergens have been published in several studies in the past, the data have not been collated to facilitate cross-comparison. Salient characteristics of the three most recently identified latex allergens, Hev b 11, 12 and 13 are described, whereas new findings on some of the previously recognized allergens are examined. Hev b 2 is viewed from the standpoint of allergenicity and protein glycosylation, Hev b 4 in relation to its biochemical identity and molecular cloning, Hev b 5 with respect to its recombinant form, and Hev b 6 in connection with conformational IgE epitopes. Reports on sensitization or allergic reaction to purified latex allergens from recent and past work are summarized. The use of latex allergens in latex allergy diagnostics is reviewed and discussed. Thirteen latex allergens have been recognized by the International Union of Immunological Societies. Based on the results of published studies, native Hev b 2, recombinant Hev b 5, native or recombinant Hev b 6, native Hev b 13, and possibly native Hev b 4 are the major allergens relevant to latex-sensitized adults. Although there is an increasing tendency to identify and characterize latex allergens largely on the basis of their recombinant forms, not all such recombinant proteins have been fully validated against their native counterparts with respect to clinical significance.

Allergens labeling on French processed foods - an Oqali study.

PubMed

Battisti, Charlène; Chambefort, Amélie; Digaud, Olivier; Duplessis, Barbara; Perrin, Cécile; Volatier, Jean-Luc; Gauvreau-Béziat, Julie; Menard, Céline

2017-07-01

The French Observatory of Food Quality (Oqali) aims at collecting all nutritional data provided on labels of processed foods (nutritional information and composition), at branded products level, in order to follow nutritional labeling changes over time. This study carries out an overview of allergens labeling frequencies by distinguishing allergens used in recipes from those listed on precautionary statements, for the fourteen allergen categories for which labeling is mandatory according to European legislation. 17,309 products were collected, between 2008 and 2012, from 26 food categories. Products were classified per family and type of brand (national brands, retailer brands, entry-level retailer brands, hard discount, and specialized retailer brands). Allergenic ingredients were identified from ingredients lists and precautionary statements. 73% of the 17,309 products studied contained at least one allergen in their ingredients list and 39% had a precautionary statement for one or more allergens. Milk (53%), gluten (41%), and egg (22%) were the most commonly used allergens in ingredients lists. For precautionary statement, nuts (20%), egg (14%), peanut (13%), soybean (12%), and milk (11%) were the most common allergens listed. Precautionary statement was most frequently found among first-price products (hard discount and entry-level retailer brands). National brands seemed to use it less frequently. For all these results, differences depended both on food categories and allergen categories. This study will enable to follow allergens labeling and their use as ingredients over time, particularly by assessing an hypothetical increase in allergens presence in processed food.

Animal Allergens and Their Presence in the Environment

PubMed Central

Zahradnik, Eva; Raulf, Monika

2014-01-01

Exposure to animal allergens is a major risk factor for sensitization and allergic diseases. Besides mites and cockroaches, the most important animal allergens are derived from mammals. Cat and dog allergies affect the general population; whereas, allergies to rodents or cattle is an occupational problem. Exposure to animal allergens is not limited to direct contact to animals. Based on their aerodynamic properties, mammalian allergens easily become airborne, attach to clothing and hair, and can be spread from one environment to another. For example, the major cat allergen Fel d 1 was frequently found in homes without pets and in public buildings, including schools, day-care centers, and hospitals. Allergen concentrations in a particular environment showed high variability depending on numerous factors. Assessment of allergen exposure levels is a stepwise process that involves dust collection, allergen quantification, and data analysis. Whereas a number of different dust sampling strategies are used, ELISA assays have prevailed in the last years as the standard technique for quantification of allergen concentrations. This review focuses on allergens arising from domestic, farm, and laboratory animals and describes the ubiquity of mammalian allergens in the human environment. It includes an overview of exposure assessment studies carried out in different indoor settings (homes, schools, workplaces) using numerous sampling and analytical methods and summarizes significant factors influencing exposure levels. However, methodological differences among studies have contributed to the variability of the findings and make comparisons between studies difficult. Therefore, a general standardization of methods is needed and recommended. PMID:24624129

HpARI Protein Secreted by a Helminth Parasite Suppresses Interleukin-33.

PubMed

Osbourn, Megan; Soares, Dinesh C; Vacca, Francesco; Cohen, E Suzanne; Scott, Ian C; Gregory, William F; Smyth, Danielle J; Toivakka, Matilda; Kemter, Andrea M; le Bihan, Thierry; Wear, Martin; Hoving, Dennis; Filbey, Kara J; Hewitson, James P; Henderson, Holly; Gonzàlez-Cìscar, Andrea; Errington, Claire; Vermeren, Sonja; Astier, Anne L; Wallace, William A; Schwarze, Jürgen; Ivens, Alasdair C; Maizels, Rick M; McSorley, Henry J

2017-10-17

Infection by helminth parasites is associated with amelioration of allergic reactivity, but mechanistic insights into this association are lacking. Products secreted by the mouse parasite Heligmosomoides polygyrus suppress type 2 (allergic) immune responses through interference in the interleukin-33 (IL-33) pathway. Here, we identified H. polygyrus Alarmin Release Inhibitor (HpARI), an IL-33-suppressive 26-kDa protein, containing three predicted complement control protein (CCP) modules. In vivo, recombinant HpARI abrogated IL-33, group 2 innate lymphoid cell (ILC2) and eosinophilic responses to Alternaria allergen administration, and diminished eosinophilic responses to Nippostrongylus brasiliensis, increasing parasite burden. HpARI bound directly to both mouse and human IL-33 (in the cytokine's activated state) and also to nuclear DNA via its N-terminal CCP module pair (CCP1/2), tethering active IL-33 within necrotic cells, preventing its release, and forestalling initiation of type 2 allergic responses. Thus, HpARI employs a novel molecular strategy to suppress type 2 immunity in both infection and allergy. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Release of Bet v 1 from birch pollen from 5 European countries. Results from the HIALINE study

NASA Astrophysics Data System (ADS)

Buters, Jeroen T. M.; Thibaudon, Michel; Smith, Matt; Kennedy, Roy; Rantio-Lehtimäki, Auli; Albertini, Roberto; Reese, Gerald; Weber, Bernhard; Galan, Carmen; Brandao, Rui; Antunes, Celia M.; Jäger, Siegfried; Berger, Uwe; Celenk, Sevcan; Grewling, Łukasz; Jackowiak, Bogdan; Sauliene, Ingrida; Weichenmeier, Ingrid; Pusch, Gudrun; Sarioglu, Hakan; Ueffing, Marius; Behrendt, Heidrun; Prank, Marje; Sofiev, Mikhail; Cecchi, Lorenzo; Hialine Working Group

2012-08-01

Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network). Pollen count was assessed with Hirst type pollen traps at 10 l min-1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min-1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient. Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration. Although Bet v 1 is a mixture of different isoforms, its fingerprint is constant across Europe. Bet v 1 was also exclusively linked to pollen. Pollen from different days varied >10-fold in allergen release. Thus exposure to allergen is inaccurately monitored by only monitoring birch pollen grains. Indeed, a humanized basophil activation test correlated much better with allergen concentrations in ambient air than with pollen count. Monitoring the allergens themselves together with pollen in ambient air might be an improvement in allergen exposure assessment.

Release of Bet v 1 from birch pollen from 5 European countries. Results from the HIALINE study

NASA Astrophysics Data System (ADS)

The HIALINE working Group; Buters, Jeroen T. M.; Thibaudon, Michel; Smith, Matt; Kennedy, Roy; Rantio-Lehtimäki, Auli; Albertini, Roberto; Reese, Gerald; Weber, Bernhard; Galan, Carmen; Brandao, Rui; Antunes, Celia M.; Jäger, Siegfried; Berger, Uwe; Celenk, Sevcan; Grewling, Łukasz; Jackowiak, Bogdan; Sauliene, Ingrida; Weichenmeier, Ingrid; Pusch, Gudrun; Sarioglu, Hakan; Ueffing, Marius; Behrendt, Heidrun; Prank, Marje; Sofiev, Mikhail; Cecchi, Lorenzo

2012-08-01

Exposure to allergens is pivotal in determining sensitization and allergic symptoms in individuals. Pollen grain counts in ambient air have traditionally been assessed to estimate airborne allergen exposure. However, the exact allergen content of ambient air is unknown. We therefore monitored atmospheric concentrations of birch pollen grains and the matched major birch pollen allergen Bet v 1 simultaneously across Europe within the EU-funded project HIALINE (Health Impacts of Airborne Allergen Information Network).Pollen count was assessed with Hirst type pollen traps at 10 l min-1 at sites in France, United Kingdom, Germany, Italy and Finland. Allergen concentrations in ambient air were sampled at 800 l min-1 with a Chemvol® high-volume cascade impactor equipped with stages PM > 10 μm, 10 μm > PM > 2.5 μm, and in Germany also 2.5 μm > PM > 0.12 μm. The major birch pollen allergen Bet v 1 was determined with an allergen specific ELISA. Bet v 1 isoform patterns were analyzed by 2D-SDS-PAGE blots and mass spectrometric identification. Basophil activation was tested in an FcɛR1-humanized rat basophil cell line passively sensitized with serum of a birch pollen symptomatic patient.Compared to 10 previous years, 2009 was a representative birch pollen season for all stations. About 90% of the allergen was found in the PM > 10 μm fraction at all stations. Bet v 1 isoforms pattern did not vary substantially neither during ripening of pollen nor between different geographical locations. The average European allergen release from birch pollen was 3.2 pg Bet v 1/pollen and did not vary much between the European countries. However, in all countries a >10-fold difference in daily allergen release per pollen was measured which could be explained by long-range transport of pollen with a deviating allergen release. Basophil activation by ambient air extracts correlated better with airborne allergen than with pollen concentration.Although Bet v 1 is a mixture of different isoforms, its fingerprint is constant across Europe. Bet v 1 was also exclusively linked to pollen. Pollen from different days varied >10-fold in allergen release. Thus exposure to allergen is inaccurately monitored by only monitoring birch pollen grains. Indeed, a humanized basophil activation test correlated much better with allergen concentrations in ambient air than with pollen count. Monitoring the allergens themselves together with pollen in ambient air might be an improvement in allergen exposure assessment.

Food allergy animal models: an overview.

PubMed

Helm, Ricki M

2002-05-01

Specific food allergy is characterized by sensitization to innocuous food proteins with production of allergen-specific IgE that binds to receptors on basophils and mast cells. Upon recurrent exposure to the same allergen, an allergic response is induced by mediator release following cross-linking of cell-bound allergen-specific IgE. The determination of what makes an innocuous food protein an allergen in predisposed individuals is unknown; however, mechanistic and protein allergen predictive models are being actively investigated in a number of animal models. Currently, there is no animal model that will actively profile known food allergens, predict the allergic potential of novel food proteins, or demonstrate clinically the human food allergic sensitization/allergic response. Animal models under investigation include mice, rats, the guinea pig, atopic dog, and neonatal swine. These models are being assessed for production of IgE, clinical responses to re-exposure, and a ranking of food allergens (based on potency) including a nonfood allergen protein source. A selection of animal models actively being investigated that will contribute to our understanding of what makes a protein an allergen and future predictive models for assessing the allergenicity of novel proteins is presented in this review.

Alternaria and Cladosporium Fungal Allergen Epitopes are Denatured by Sodium Hypochlorite

PubMed Central

2009-01-01

Background Fungal allergens are ubiquitous; however, little progress has been made understanding fungal allergenic material removal from indoor environments. Purpose We investigated removal of environmental allergenic material derived from Alternaria and Cladosporium using sodium hypochlorite in vivo and in vitro. Methods Freeze dried allergen extract from Alternaria alternata and Cladosporium herbarum was treated with hypochlorite concentrations of 322, 88, 38, 16, 3, 0.3, and 0 mM, respectively. Remaining native allergenic material was quantified using enzyme immunoassay and remaining viable fungal material was evaluated. Results The results of treating Alternaria or Cladosporium extract with sodium hypochlorite are immediate and obvious. Concentrations greater than 100 mM remove color and concentrations between 100 and 38 mM partially uncolored the extract. Immunoassay for total antigenic and allergenic material remaining after treatment with sodium hypochlorite including 2 concentrations recommended for killing fungus confirmed a general destruction of antigenic and allergenic material at concentrations of 38 mM or greater. Conclusions This work confirms the ability of solutions of sodium hypochlorite to denature fungal allergenic material from common outdoor and indoor fungi A. alternata and C. herbarum. Destruction of recognized antigenic and allergenic epitopes occurs at hypochlorite concentrations commonly used for household cleaning. PMID:23282316

Mold Allergens in Respiratory Allergy: From Structure to Therapy

PubMed Central

Twaroch, Teresa E; Curin, Mirela; Swoboda, Ines

2015-01-01

Allergic reactions to fungi were described 300 years ago, but the importance of allergy to fungi has been underestimated for a long time. Allergens from fungi mainly cause respiratory and skin symptoms in sensitized patients. In this review, we will focus on fungi and fungal allergens involved in respiratory forms of allergy, such as allergic rhinitis and asthma. Fungi can act as indoor and outdoor respiratory allergen sources, and depending on climate conditions, the rates of sensitization in individuals attending allergy clinics range from 5% to 20%. Due to the poor quality of natural fungal allergen extracts, diagnosis of fungal allergy is hampered, and allergen-specific immunotherapy is rarely given. Several factors are responsible for the poor quality of natural fungal extracts, among which the influence of culture conditions on allergen contents. However, molecular cloning techniques have allowed us to isolate DNAs coding for fungal allergens and to produce a continuously growing panel of recombinant allergens for the diagnosis of fungal allergy. Moreover, technologies are now available for the preparation of recombinant and synthetic fungal allergen derivatives which can be used to develop safe vaccines for the treatment of fungal allergy. PMID:25840710

Identification of the major allergens of Charybdis feriatus (red crab) and its cross-reactivity with Portunus pelagicus (blue crab).

PubMed

Misnan, Rosmilah; Murad, Shahnaz; Yadzir, Zailatul Hani Mohd; Abdullah, Noormalin

2012-12-01

Tropomyosin and arginine kinase have been identified as the major allergens in multiple species of crab. Charybdis feriatus is an important commercial crab in this country. To characterize the major allergens of C. feriatus using a proteomics approach and subsequently to identify the allergens involved in cross-reactivity with Portunus pelagicus. Raw and boiled extracts of the crabs were prepared from crab meat. The protein profile of the extracts was determined by SDS-PAGE and two-dimensional electrophoresis (2-DE). Major allergens were identified by the immunoblotting test using sera from 50 patients with crab allergy. The major allergens were further identified by 2-DE immunoblotting. The major allergenic spots were then excised, digested by trypsin and identified by mass spectrometry analysis. The immunoblotting inhibition test was performed to study the crossreactivity between red crab and blue crab allergens using sera from 20 patients with allergy to both red and blue crabs. At least 20 protein bands between 13 to 250 kDa were detected in the SDS-PAGE gel of raw extract, while boiled extract procuced fewer protein bands. Proteins of 36 kDa and 41 kDa were recognized as the major allergens of the crab. The major allergenic spot sequences of the 36 and 41 kDa proteins were identified as crab tropomyosin and arginine kinase, respectively. All IgE-binding proteins, including both major allergens, were found to be cross-creative with P. pelagicus allergens. In addition to tropomyosin, arginine kinase was also identified as the major allergen of C. feriatus among our local crab-allergic patients. Cross-reactivity of this crab with P. pelagicus was demonstrated in this study.

Comparison of serum concentrations of environmental allergen-specific IgE in atopic and healthy (nonatopic) horses.

PubMed

Wilkołek, P; Sitkowski, W; Szczepanik, M; Adamek, Ł; Pluta, M; Taszkun, I; Gołyński, M; Malinowska, A

2017-12-01

Allergic responses in humans, horses and other species are mediated by immunoglobulin E (IgE) antibodies. Serum testing to detect allergen-specific IgE antibodies has been developed for dogs, cats and horses; this allows for the identification of allergens and determination of appropriate allergen- specific immunotherapies. This study compared serum allergen-specific IgE concentrations in atopic and healthy horses. The study was performed on Malopolski breed atopic (n=21) and nonatopic (n=21) clinically healthy horses. Allergen-specific IgE serum concentrations were measured in summer seasons of 2008-2015 using a monoclonal anti-IgE antibody. A Northern and Central European allergen panel containing mite, insect, mould and plant pollen allergens, including 15 tests of individual allergens and 5 tests of allergen mixtures was used. The mean allergen-specific IgE concentrations in the atopic and normal horse populations were compared. Among the atopic horses, the strongest positive reactions occurred against the storage mites Tyrophagus putrescentiae and the domestic mite Dermatophagoides farinae. The atopic horses also demonstrated high IgE concentrations against insects, particularly Tabanus sp., the plant pollens colza, cultivated rye and the mould pollen mixture Aspergillus/Penicillium. No horses in the atopic group were IgE-negative. Among all mite, insect, mould and some plant allergen groups the differences in mean specific IgE concentrations between allergic and healthy horses were significant. The mean IgE concentrations for most allergen groups were significantly higher in the atopic horses than in the healthy animals. However, a high incidence of positive reactions was observed in both healthy and allergic horses. Our results showed a high frequency of polysensitization in atopic horses. Copyright© by the Polish Academy of Sciences.

Greater Real-Life Diagnostic Efficacy of Allergen Molecule-Based Diagnosis for Prescription of Immunotherapy in an Area with Multiple Pollen Exposure

PubMed Central

Saltabayeva, Ulbosin; Garib, Victoria; Morenko, Marina; Rosenson, Rafail; Ispayeva, Zhanat; Gatauova, Madina; Zulus, Loreta; Karaulov, Alexander; Gastager, Felix; Valenta, Rudolf

2017-01-01

Background Allergen molecule-based diagnosis has been suggested to facilitate the identification of disease-causing allergen sources and the prescription of allergen-specific immunotherapy (AIT). The aim of the current study was to compare allergen molecule-based IgE serology with allergen extract-based skin testing for the identification of the disease-causing allergen sources. The study was conducted in an area where patients are exposed to pollen from multiple sources (trees, grasses, and weeds) at the same time to compare the diagnostic efficiency of the 2 forms of diagnosis. Methods Patients from Astana, Kazakhstan, who suffered from pollen-induced allergy (n = 95) were subjected to skin prick testing (SPT) with a local panel of tree pollen, grass pollen, and weed pollen allergen extracts and IgE antibodies specific for marker allergen molecules (nArt v 1, nArt v 3, rAmb a 1, rPhl p 1, rPhl p 5, rBet v 1) were measured by ImmunoCAP. Direct and indirect costs for diagnosis based on SPT and marker allergen-based IgE serology as well as direct costs for immunotherapy depending on SPT and serological test results were calculated. Results The costs for SPT-based diagnosis per patient were lower than the costs for allergen molecule-based IgE serology. However, allergen molecule-based serology was more precise in detecting the disease-causing allergen sources. A lower number of immunotherapy treatments (n = 119) was needed according to molecular diagnosis as compared to extract-based diagnosis (n = 275), which considerably reduced the total costs for diagnosis and for a 3-year treatment from EUR 1,112.30 to 521.77 per patient. Conclusions The results from this real-life study show that SPT is less expensive than allergen molecule-based diagnostic testing, but molecular diagnosis allowed more precise prescription of immunotherapy which substantially reduced treatment costs and combined costs for diagnosis and treatment. PMID:28654920

Correlation between skin-prick testing, individual specific IgE tests, and a multiallergen IgE assay for allergy detection in patients with chronic rhinitis.

PubMed

Cho, Jae Hoon; Suh, Jeffrey D; Kim, Jin Kook; Hong, Seok-Chan; Park, Il-Ho; Lee, Heung-Man

2014-01-01

Allergy test results can differ based on the method used. The most common tests include skin-prick testing (SPT) and in vitro tests to detect allergen-specific IgE. This study was designed to assess allergy test results using SPT, individual specific IgE tests, and a multiallergen IgE assay (multiple allergen simultaneous test) in patients with chronic rhinitis and controls. One hundred forty total patients were prospectively enrolled in the study, including 100 patients with chronic rhinitis and 40 control patients without atopy. All eligible patients underwent SPT, serum analysis using individual specific IgE test, and multiple allergen simultaneous test against 10 common allergens. Allergy test results were then compared to identify correlation and interest agreement. There was an 81-97% agreement between SPT and individual specific IgE test in allergen detection and an 80-98% agreement between SPT and multiple allergen simultaneous test. Individual specific IgE test and multiple allergen simultaneous test allergy detection prevalence was generally similar to SPT in patients with chronic rhinitis. All control patients had negative SPT (0/40), but low positive results were found with both individual specific IgE test (5-12.5%) and multiple allergen simultaneous test (2.5-7.5%) to some allergens, especially cockroach, Dermatophagoides farina, and ragweed. Agreement and correlation between individual specific IgE test and multiple allergen simultaneous test were good to excellent for a majority of tested allergens. This study shows good agreement and correlation between SPT with individual specific IgE test and multiple allergen simultaneous test on a majority of the tested allergens for patients with chronic rhinitis. Comparing the two in vitro tests, individual specific IgE test agrees with SPT better than multiple allergen simultaneous test.

Scientific advancement of novel protein allergenicity evaluation: an overview of work from the HESI Protein Allergenicity Technical Committee (2000-2008).

PubMed

Thomas, Karluss; MacIntosh, Sue; Bannon, Gary; Herouet-Guicheney, Corinne; Holsapple, Michael; Ladics, Gregory; McClain, Scott; Vieths, Stefan; Woolhiser, Michael; Privalle, Laura

2009-06-01

The safety assessment of genetically modified crops includes the evaluation for potential allergenicity. The current 'state-of-the-science' utilizes a weight of evidence approach, as outlined by the Codex Alimentarius commission (Alinorm 03/34 A), recognizing no single endpoint is predictive of the allergenic potential of a novel protein. This approach evaluates: whether the gene source is allergenic, sequence similarity to known allergens, and protein resistance to pepsin in vitro. If concerns are identified, serological studies may be necessary to determine if a protein has IgE binding similar to known allergens. Since there was a lack of standardized/validated methods to conduct the allergenicity assessment, a committee was assembled under the International Life Sciences Institute Health and Environmental Sciences Institute to address this issue. Over the last eight years, the Protein Allergenicity Technical Committee has convened workshops and symposia with allergy experts and government authorities to refine methods that underpin the assessment for potential protein allergenicity. This publication outlines this ongoing effort, summarizing workshops and formal meetings, referencing publications, and highlighting outreach activities. The purpose is to (1) outline 'the state-of-the-science' in predicting protein allergenicity in the context of current international recommendations for novel protein safety assessment, and (2) identify approaches that can be improved and future research needs.

New routes of allergen immunotherapy.

PubMed

Aricigil, Mitat; Muluk, Nuray Bayar; Sakarya, Engin Umut; Sakalar, Emine Güven; Senturk, Mehmet; Reisacher, William R; Cingi, Cemal

2016-11-01

Allergen immunotherapy is the only cure for immunoglobulin E mediated type I respiratory allergies. Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are the most common treatments. In this article, we reviewed new routes of allergen immunotherapy. Data on alternative routes to allow intralymphatic immunotherapy (ILIT), epicutaneous immunotherapy (EPIT), local nasal immunotherapy (LNIT), oral immunotherapy (OIT), and oral mucosal immunotherapy (OMIT) were gathered from the literature and were discussed. ILIT features direct injection of allergens into lymph nodes. ILIT may be clinically effective after only a few injections and induces allergen-specific immunoglobulin G, similarly to SCIT. A limitation of ILIT is that intralymphatic injections are required. EPIT features allergen administration by using patches mounted on the skin. EPIT seeks to target epidermal antigen-presenting Langerhans cells rather than mast cells or the vasculature; this should reduce both local and systemic adverse effects. LNIT involves the spraying of allergen extracts into the nasal cavity. Natural or chemically modified allergens (the latter, termed allergoids, lack immunoglobulin E reactivity) are prepared in a soluble form. OIT involves the regular administration of small amounts of a food allergen by mouth and commences with low oral doses, which are then increased as tolerance develops. OMIT seeks to deliver allergenic proteins to an expanded population of Langerhans cells in the mucosa of the oral cavity. ILIT, EPIT, LNIT, OIT, and OMIT are new routes for allergen immunotherapy. They are safe and effective.

Minimum prick test panel for adult patients with asthma and rhinitis in Ankara, Turkey.

PubMed

Comert, Sule; Demir, A Ugur; Karakaya, Gul; Kalyoncu, A Fuat

2014-05-01

Determination of the number and type of allergens needed to be tested in epidemiological studies is important in order to identify most of the sensitized subjects with a cost-effective approach. This study aimed to investigate the minimum skin prick test panel for the identification of at least 95% of the sensitized subjects with symptoms of asthma and/or allergic rhinitis (AR) in Ankara, Turkey. Skin prick test results of 7492 patients who were referred to our outpatient clinic with clinical symptoms of asthma and/or AR between 1991 and 2005 were evaluated retrospectively. Seven allergens were tested in all and 13 allergens in 4202 patients. The allergen group needed for detection of 95% of the sensitized subjects was determined for both the 7 and 13 allergen panels. The study protocol was approved by the local ethics committee of Hacettepe University. The atopy prevalences in the whole study population and in 4202 patients tested with the 13 allergen panel were calculated as 32.2% and 42.6%, respectively. Three allergens (Phleum pratense, Dermatophagoides pteronyssinus and Artemisia vulgaris) within the 7 allergen panel were adequate for the identification of at least 95% of the sensitized subjects. Olea europae was added to the previous three allergens when the 13 allergen panel was applied. Three to four allergens are sufficient for identification at least 95% of sensitized subjects with asthma and/or AR in Ankara, Turkey.

AllergenOnline: A peer-reviewed, curated allergen database to assess novel food proteins for potential cross-reactivity.

PubMed

Goodman, Richard E; Ebisawa, Motohiro; Ferreira, Fatima; Sampson, Hugh A; van Ree, Ronald; Vieths, Stefan; Baumert, Joseph L; Bohle, Barbara; Lalithambika, Sreedevi; Wise, John; Taylor, Steve L

2016-05-01

Increasingly regulators are demanding evaluation of potential allergenicity of foods prior to marketing. Primary risks are the transfer of allergens or potentially cross-reactive proteins into new foods. AllergenOnline was developed in 2005 as a peer-reviewed bioinformatics platform to evaluate risks of new dietary proteins in genetically modified organisms (GMO) and novel foods. The process used to identify suspected allergens and evaluate the evidence of allergenicity was refined between 2010 and 2015. Candidate proteins are identified from the NCBI database using keyword searches, the WHO/IUIS nomenclature database and peer reviewed publications. Criteria to classify proteins as allergens are described. Characteristics of the protein, the source and human subjects, test methods and results are evaluated by our expert panel and archived. Food, inhalant, salivary, venom, and contact allergens are included. Users access allergen sequences through links to the NCBI database and relevant references are listed online. Version 16 includes 1956 sequences from 778 taxonomic-protein groups that are accepted with evidence of allergic serum IgE-binding and/or biological activity. AllergenOnline provides a useful peer-reviewed tool for identifying the primary potential risks of allergy for GMOs and novel foods based on criteria described by the Codex Alimentarius Commission (2003). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Food allergen law and the Food Allergen Labeling and Consumer Protection Act of 2004: falling short of true protection for food allergy sufferers.

PubMed

Roses, Jonathan B

2011-01-01

In 2004, Congress mandated labeling of food allergens on packaged foods for the first time by passing the Food Allergen Labeling and Consumer Protection Act (FALCPA). FALCPA requires that manufacturers of foods containing one of the eight major allergens responsible for 90 percent of food allergies either state on the food's packaging that the food contains the allergen, or refers to the allergen by a name easily understandable by consumers in the ingredients listing. Despite this important first step in protecting consumers with food allergies, FALCPA left unregulated the use of conditional precautionary statements (e.g., "may contain [allergen]"), which many manufacturers have used as a low-cost shield to liability. Further, FALCPA applies only to packaged foods, and does not mandate listing of food allergen ingredients in restaurants. This article discusses the history of food allergen litigation in the United States, highlighting the problems plaintiffs have faced in seeking recovery for allergic reactions to a defendants' food product, and some of the practical difficulties still extant due to the lack of regulation of precautionary statements. Also presented is a review of the Massachusetts Food Allergy Awareness Act, the first state legislation requiring restaurants to take an active role in educating employees and consumers about the presence and dangers of food allergens.

Fractionation and immunological characterization of allergens and allergoids of Prosopis juliflora pollen.

PubMed

Thakur, I S; Kamal; Mishra, S

1991-06-01

Allergoids of Prosopis juliflora pollen were prepared by formalinization of crude allergen and glycoprotein. Fractionation of crude allergen and allergoids on Sephadex G-100 resulted in separation of proteins of varying molecular size and a glycoprotein of 81 to 13 KD. Allergoids prepared from the glycoprotein fractionated into two proteins of approximately 200 KD and more than 200 KD. Crossed immunoelectrophoresis indicated 12 and gel diffusion test 3 precipitating antigens incrude allergen extract; by these tests allergoids depicted 8 and 3 precipitin bands, respectively. The precipitin analysis showed heterogeneity of allergenic determinants and also variation in cross-immunogenicity of the formalinized derivatives. The skin prick and radioallergosorbent tests depicted greater activity of fractionated crude allergens than the allergoids. The above tests suggest altered and concealed antigenic determinants as result of formalinization of P. juliflora pollen which, however, showed reduced allergenic activity relative to the native allergen.

Investigation of endogenous soybean food allergens by using a 2-dimensional gel electrophoresis approach.

PubMed

Rouquié, David; Capt, Annabelle; Eby, William H; Sekar, Vaithilingam; Hérouet-Guicheney, Corinne

2010-12-01

As part of the safety assessment of genetically modified (GM) soybean, 2-dimensional gel electrophoresis analyses were performed with the isoxaflutole and glyphosate tolerant soybean FG72, its non-GM near-isogenic counterpart (Jack) and three commercial non-GM soybean lines. The objective was to compare the known endogenous human food allergens in seeds in the five different soybean lines in order to evaluate any potential unintended effect(s) of the genetic modification. In total, 37 protein spots representing five well known soybean food allergen groups were quantified in each genotype. Qualitatively, all the allergenic proteins were detected in the different genetic backgrounds. Quantitatively, among 37 protein spots, the levels of accumulation of three allergens were slightly lower in the GM soybean than in the non-GM counterparts. Specifically, while the levels of two of these three allergens fell within the normal range of variation observed in the four non-GM varieties, the level of the third allergen was slightly below the normal range. Overall, there was no significant increase in the level of allergens in FG72 soybean seeds. Therefore, the FG72 soybean can be considered as safe as its non-GM counterpart with regards to endogenous allergenicity. Additional research is needed to evaluate the biological variability in the levels of endogenous soybean allergens and the correlation between level of allergens and allergenic potential in order to improve the interpretation of these data in the safety assessment of GM soybean context. Copyright © 2010 Elsevier Inc. All rights reserved.

An overview of fruit allergy and the causative allergens.

PubMed

Hassan, A K G; Venkatesh, Y P

2015-11-01

Plant allergens, being one of the most widespread allergenic substances, are hard to avoid. Hence, their identification and characterization are of prime importance for the diagnosis and treatment of food allergy. The reported allergies to fruits mainly evoke oral allergy syndrome caused by the presence of cross-reactive IgE to certain pollens and thus, allergy to fruits has also been linked to particular pollens. Many fruit allergies are being studied for their causative allergens, and are being characterized. Some tropical or exotic fruits are responsible for region-specific allergies for which only limited information is available, and generally lack allergen characterization. From a survey of the literature on fruit allergy, it is clear that some common fruits (apple, peach, musk melon, kiwi fruit, cherry, grape, strawberry, banana, custard apple, mango and pomegranate) and their allergens appear to be at the center of current research on food allergy. The present review focuses on common fruits reported as allergenic and their identified allergens; a brief description of allergens from six rare/tropical fruits is also covered.

Vaccine development for allergen-specific immunotherapy based on recombinant allergens and synthetic allergen peptides: Lessons from the past and novel mechanisms of action for the future

PubMed Central

Valenta, Rudolf; Campana, Raffaela; Focke-Tejkl, Margit; Niederberger, Verena

2016-01-01

In the past, the development of more effective, safe, convenient, broadly applicable, and easy to manufacture vaccines for allergen-specific immunotherapy (AIT) has been limited by the poor quality of natural allergen extracts. Progress made in the field of molecular allergen characterization has now made it possible to produce defined vaccines for AIT and eventually for preventive allergy vaccination based on recombinant DNA technology and synthetic peptide chemistry. Here we review the characteristics of recombinant and synthetic allergy vaccines that have reached clinical evaluation and discuss how molecular vaccine approaches can make AIT more safe and effective and thus more convenient. Furthermore, we discuss how new technologies can facilitate the reproducible manufacturing of vaccines of pharmaceutical grade for inhalant, food, and venom allergens. Allergy vaccines in clinical trials based on recombinant allergens, recombinant allergen derivatives, and synthetic peptides allow us to target selectively different immune mechanisms, and certain of those show features that might make them applicable not only for therapeutic but also for prophylactic vaccination. PMID:26853127

Effect of processing on recovery and variability associated with immunochemical analytical methods for multiple allergens in a single matrix: sugar cookies.

PubMed

Khuda, Sefat; Slate, Andrew; Pereira, Marion; Al-Taher, Fadwa; Jackson, Lauren; Diaz-Amigo, Carmen; Bigley, Elmer C; Whitaker, Thomas; Williams, Kristina M

2012-05-02

Among the major food allergies, peanut, egg, and milk are the most common. The immunochemical detection of food allergens depends on various factors, such as the food matrix and processing method, which can affect allergen conformation and extractability. This study aimed to (1) develop matrix-specific incurred reference materials for allergen testing, (2) determine whether multiple allergens in the same model food can be simultaneously detected, and (3) establish the effect of processing on reference material stability and allergen detection. Defatted peanut flour, whole egg powder, and spray-dried milk were added to cookie dough at seven incurred levels before baking. Allergens were measured using five commercial enzyme-linked immunosorbent assay (ELISA) kits. All kits showed decreased recovery of all allergens after baking. Analytical coefficients of variation for most kits increased with baking time, but decreased with incurred allergen level. Thus, food processing negatively affects the recovery and variability of peanut, egg, and milk detection in a sugar cookie matrix when using immunochemical methods.

Impact of urban air pollution on the allergenicity of Aspergillus fumigatus conidia: Outdoor exposure study supported by laboratory experiments.

PubMed

Lang-Yona, Naama; Shuster-Meiseles, Timor; Mazar, Yinon; Yarden, Oded; Rudich, Yinon

2016-01-15

Understanding the chemical interactions of common allergens in urban environments may help to decipher the general increase in susceptibility to allergies observed in recent decades. In this study, asexual conidia of the allergenic mold Aspergillus fumigatus were exposed to air pollution under natural (ambient) and controlled (laboratory) conditions. The allergenic activity was measured using two immunoassays and supported by a protein mass spectrometry analysis. The allergenicity of the conidia was found to increase by 2-5 fold compared to the control for short exposure times of up to 12h (accumulated exposure of about 50 ppb NO2 and 750 ppb O3), possibly due to nitration. At higher exposure times, the allergenicity increase lessened due to protein deamidation. These results indicate that during the first 12h of exposure, the allergenic potency of the fungal allergen A. fumigatus in polluted urban environments is expected to increase. Additional work is needed in order to determine if this behavior occurs for other allergens. Copyright © 2015 Elsevier B.V. All rights reserved.

Detection of cross-reactivity for atopic immunoglobulin E against multiple allergens.

PubMed

Chiou, Yee-Hsuan; Yuo, Chung-Yee; Wang, Lin-Yu; Huang, Shiao-ping

2003-03-01

The existence of specific immunoglobulin E (IgE) allows us to determine the allergens that cause the allergic disease. For the purposes of allergen avoidance and immunotherapy, the measurement of specific IgE is widely applied in clinical laboratories. However, if IgE from the serum of an allergic patient exhibits reactivity to multiple allergens, it would cause a problem. The present study analyzes whether the serum IgE with multiple reactivity is due to the presence of unique IgE against the common epitope shared by different allergens or the presence of multiple IgEs against different epitopes on different allergens. The quantitative-competitive inhibition tests and the immunoblotting were applied to analyze the immunosimilarity among examined allergens. The result shows that the competitive inhibition of IgE binding between shrimp and crab allergens is higher than those between either shrimp and cockroach or between crab and cockroach. Furthermore, the results of immunoblotting are consistent with those of quantitative-competitive inhibition tests. These results allow us to detect the cross-reactivity for atopic IgE against multiple allergens.

Identification of novel allergen in edible insect, Gryllus bimaculatus and its cross-reactivity with Macrobrachium spp. allergens.

PubMed

Srinroch, Chutima; Srisomsap, Chantragan; Chokchaichamnankit, Daranee; Punyarit, Phaibul; Phiriyangkul, Pharima

2015-10-01

Edible insects have recently been promoted as a source of protein and have a high nutrition value. Identification of allergens and cross-reactivity between Macrobrachium spp. and the field cricket (Gryllus bimaculatus) is necessary for food safety control and to assist in the diagnosis and therapy of allergy symptoms. Denaturing polyacrylamide gel electrophoresis (SDS-PAGE) was used to separate proteins. Allergens were determined and identified by IgE-immunoblotting with pooled sera from prawn-allergic patients (n=16) and LC-MS/MS. Arginine kinase (AK) and glyceraldehyde 3-phosphate dehydrogenase (GAPDH) were determined as the important allergens in muscle of Macrobrachium rosenbergii whereas, hemocyanin (HC) was identified as an allergen in Macrobrachium spp. The allergens in Macrobrachium lanchesteri were identified as AK and HC. In addition, hexamerin1B (HEX1B) was identified as a novel and specific allergen in G. bimaculatus. The important allergen in G. bimaculatus and Macrobrachium spp. is AK and was found to cross-react between both species. Copyright © 2015 Elsevier Ltd. All rights reserved.

Evaluation of three different histamine concentrations in intradermal testing of normal cats and attempted determination of 'irritant' threshold concentrations for 48 allergens.

PubMed

Austel, Michaela; Hensel, Patrick; Jackson, Dawn; Vidyashankar, Anand; Zhao, Ying; Medleau, Linda

2006-06-01

The purpose of this study was to determine the optimal histamine concentration and 'irritant' allergen threshold concentrations in intradermal testing (IDT) in normal cats. Thirty healthy cats were tested with three different histamine concentrations and four different concentrations of each allergen. The optimal histamine concentration was determined to be 1: 50,000 w/v (0.05 mg mL(-1)). Using this histamine concentration, the 'irritant' threshold concentration for most allergens was above the highest concentrations tested (4,000 PNU mL(-1) for 41 allergens and 700 PNU mL(-1) for human dander). The 'irritant' threshold concentration for flea antigen was determined to be 1:750 w/v. More than 10% of the tested cats showed positive reactions to Dermatophagoides farinae, Dermatophagoides pteronyssinus, housefly, mosquito and moth at every allergen concentration, which suggests that the 'irritant' threshold concentration for these allergens is below 1,000 PNU mL(-1), the lowest allergen concentration tested. Our results confirm previous studies in indicating that allergen and histamine concentrations used in feline IDT may need to be revised.

Food Production and Processing Considerations of Allergenic Food Ingredients: A Review

PubMed Central

Alvarez, Pedro A.; Boye, Joyce I.

2012-01-01

Although most consumers show no adverse symptoms to food allergens, health consequences for sensitized individuals can be very serious. As a result, the Codex General Standard for the Labelling of Prepackaged Foods has specified a series of allergenic ingredients/substances requiring mandatory declaration when present in processed prepackaged food products. Countries adhering to international standards are required to observe this minimum of eight substances, but additional priority allergens are included in the list in some countries. Enforcement agencies have traditionally focused their effort on surveillance of prepackaged goods, but there is a growing need to apply a bottom-up approach to allergen risk management in food manufacturing starting from primary food processing operations in order to minimize the possibility of allergen contamination in finished products. The present paper aims to review food production considerations that impact allergen risk management, and it is directed mainly to food manufacturers and policy makers. Furthermore, a series of food ingredients and the allergenic fractions identified from them, as well as the current methodology used for detection of these allergenic foods, is provided. PMID:22187573

Development of a novel mouse glioma model using lentiviral vectors

PubMed Central

Marumoto, Tomotoshi; Tashiro, Ayumu; Friedmann-Morvinski, Dinorah; Scadeng, Miriam; Soda, Yasushi; Gage, Fred H; Verma, Inder M

2009-01-01

We report the development of a new method to induce glioblastoma multiforme in adult immunocompetent mice by injecting Cre-loxP–controlled lentiviral vectors expressing oncogenes. Cell type- or region-specific expression of activated forms of the oncoproteins Harvey-Ras and AKT in fewer than 60 glial fibrillary acidic protein–positive cells in the hippocampus, subventricular zone or cortex of mice heterozygous for the gene encoding the tumor suppressor Tp53 were tested. Mice developed glioblastoma multiforme when transduced either in the subventricular zone or the hippocampus. However, tumors were rarely detected when the mice were transduced in the cortex. Transplantation of brain tumor cells into naive recipient mouse brain resulted in the formation of glioblastoma multiforme–like tumors, which contained CD133+ cells, formed tumorspheres and could differentiate into neurons and astrocytes. We suggest that the use of Cre-loxP–controlled lentiviral vectors is a novel way to generate a mouse glioblastoma multiforme model in a region- and cell type-specific manner in adult mice. PMID:19122659

A new subtype of progenitor cell in the mouse embryonic neocortex

PubMed Central

Wang, Xiaoqun; Tsai, Jin-Wu; LaMonica, Bridget; Kriegstein, Arnold R.

2011-01-01

A hallmark of mammalian brain evolution is cortical expansion, which reflects an increase in the number of cortical neurons established by the progenitor cell subtypes present and the number of their neurogenic divisions. Recent studies have revealed a new class of radial glia-like (oRG) progenitor cells in the human brain, which reside in the outer subventricular zone. Expansion of the subventricular zone and appearance of oRG cells may have been essential evolutionary steps leading from lissencephalic to gyrencephalic neocortex. Here we show that oRG-like progenitor cells are present in the mouse embryonic neocortex. They arise from asymmetric divisions of radial glia and undergo self-renewing asymmetric divisions to generate neurons. Moreover, mouse oRG cells undergo mitotic somal translocation whereby centrosome movement into the basal process during interphase preceeds nuclear translocation. Our finding of oRG cells in the developing rodent brain fills a gap in our understanding of neocortical expansion. PMID:21478886

Recombinant allergens

PubMed Central

Jutel, Marek; Solarewicz-Madejek, Katarzyna; Smolinska, Sylwia

2012-01-01

Allergen specific immunotherapy (SIT) is the only known causative treatment of allergic diseases. Recombinant allergen-based vaccination strategies arose from a strong need to both to improve safety and enhance efficacy of SIT. In addition, new vaccines can be effective in allergies including food allergy or atopic dermatitis, which poorly respond to the current treatment with allergen extracts. A number of successful clinical studies with both wild-type and hypoallergenic derivatives of recombinant allergens vaccines have been reported for the last decade. They showed high efficacy and safety profile as well as very strong modulation of T and B cell responses to specific allergens. PMID:23095874

Canine and feline atopic dermatitis: a review of the diagnostic options.

PubMed

Rees, C A

2001-11-01

Atopic dermatitis is an inherited pruritic skin disease in dogs and cats. This pruritic skin condition is due to the animal having an allergic reaction to environmental allergens. The environmental allergens that an individual dog or cat is allergic to are specific for that individual animal. Management options for affected dogs and cats include identification of the offending environmental allergens and subsequent avoidance of that allergen, or allergen-specific immunotherapy. Several diagnostic tests are available to veterinarians to try to identify these allergens. The pros and cons of each of these diagnostic tests will be addressed.

Food processing and allergenicity.

PubMed

Verhoeckx, Kitty C M; Vissers, Yvonne M; Baumert, Joseph L; Faludi, Roland; Feys, Marcel; Flanagan, Simon; Herouet-Guicheney, Corinne; Holzhauser, Thomas; Shimojo, Ryo; van der Bolt, Nieke; Wichers, Harry; Kimber, Ian

2015-06-01

Food processing can have many beneficial effects. However, processing may also alter the allergenic properties of food proteins. A wide variety of processing methods is available and their use depends largely on the food to be processed. In this review the impact of processing (heat and non-heat treatment) on the allergenic potential of proteins, and on the antigenic (IgG-binding) and allergenic (IgE-binding) properties of proteins has been considered. A variety of allergenic foods (peanuts, tree nuts, cows' milk, hens' eggs, soy, wheat and mustard) have been reviewed. The overall conclusion drawn is that processing does not completely abolish the allergenic potential of allergens. Currently, only fermentation and hydrolysis may have potential to reduce allergenicity to such an extent that symptoms will not be elicited, while other methods might be promising but need more data. Literature on the effect of processing on allergenic potential and the ability to induce sensitisation is scarce. This is an important issue since processing may impact on the ability of proteins to cause the acquisition of allergic sensitisation, and the subject should be a focus of future research. Also, there remains a need to develop robust and integrated methods for the risk assessment of food allergenicity. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Molecular properties of food allergens.

PubMed

Breiteneder, Heimo; Mills, E N Clare

2005-01-01

Plant food allergens belong to a rather limited number of protein families and are also characterized by a number of biochemical and physicochemical properties, many of which are also shared by food allergens of animal origin. These include thermal stability and resistance to proteolysis, which are enhanced by an ability to bind ligands, such as metal ions, lipids, or steroids. Other types of lipid interaction, including membranes or other lipid structures, represent another feature that might promote the allergenic properties of certain food proteins. A structural feature clearly related to stability is intramolecular disulfide bonds alongside posttranslational modifications, such as N-glycosylation. Some plant food allergens, such as the cereal seed storage prolamins, are rheomorphic proteins with polypeptide chains that adopt an ensemble of secondary structures resembling unfolded or partially folded proteins. Other plant food allergens are characterized by the presence of repetitive structures, the ability to form oligomers, and the tendency to aggregate. A summary of our current knowledge regarding the molecular properties of food allergens is presented. Although we cannot as yet predict the allergenicity of a given food protein, understanding of the molecular properties that might predispose them to becoming allergens is an important first step and will undoubtedly contribute to the integrative allergenic risk assessment process being adopted by regulators.

Detection of major food allergens in amniotic fluid: initial allergenic encounter during pregnancy.

PubMed

Pastor-Vargas, Carlos; Maroto, Aroa S; Díaz-Perales, Araceli; Villalba, Mayte; Esteban, Vanesa; Ruiz-Ramos, Marta; de Alba, Marta Rodriguez; Vivanco, Fernando; Cuesta-Herranz, Javier

2016-11-01

Ingestion of food allergens present in maternal milk during breastfeeding has been hypothesized as a gateway to sensitization to food; however, this process could develop during pregnancy, as the maternal-fetal interface develops a Th2- and Treg-mediated environment to protect the fetus. We hypothesized that in these surroundings, unborn children are exposed to food allergens contained in the mother's diet, possibly giving rise to first sensitization. The presence of allergens in utero was studied by analyzing amniotic fluid (AF) samples in two different stages of pregnancy: at 15-20 weeks and after delivery at term. An antibody microarray was developed to test for the most common food allergens. The array detects the presence of ten allergens from milk, fruit, egg, fish, nuts, and wheat. AF from 20 pregnant women was collected: eight after delivery at term and 12 from women who underwent diagnostic amniocentesis between weeks 15 and 20 of gestation. The presence of allergens was detected in all samples. Samples from amniocentesis had a higher allergen concentration than samples after delivery at term. We demonstrated the presence of intact major food allergens in AF samples. This early contact could explain subsequent sensitization to foods never eaten before. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Cockroach Allergen Exposure and Risk of Asthma

PubMed Central

Do, Danh C.; Zhao, Yilin; Gao, Peisong

2015-01-01

Cockroach sensitization is an important risk factor for the development of asthma. However, its underlying immune mechanisms and the genetic etiology for differences in allergic responses remain unclear. Cockroach allergens identification and their expression as biologically active recombinant proteins has provided a basis for studying the mechanisms regarding cockroach allergens induced allergic sensitization and asthma. Glycans in allergens may play a crucial role in the immunogenicity of allergic diseases. Protease-activated receptor (PAR)-2, Toll-like receptor (TLR), and C-type lectin receptors have been suggested to be important for the penetration of cockroach allergens through epithelial cells to mediate allergen uptake, dendritic cell maturation, antigen presenting cell (APC) function in T cell polarization, and cytokine production. Environmental pollutants, which often co-exist with the allergen, could synergistically elicit allergic inflammation, and aryl hydrocarbon receptor (AhR) activation and signaling may serve as a link between these two elements. Genetic factors may also play an important role in conferring the susceptibility to cockroach sensitization. Several genes have been associated with cockroach sensitization and asthma-related phenotypes. In this review, we will discuss the epidemiological evidence for cockroach allergen-induced asthma, cockroach allergens, the mechanisms regarding cockroach allergens induced innate immune responses, and the genetic basis for cockroach sensitization. PMID:26706467

A protocol for a systematic review to identify allergenic tree nuts and the molecules responsible for their allergenic properties.

PubMed

Javed, Bushra; Padfield, Philip; Sperrin, Matthew; Simpson, Angela; Mills, E N Clare

2017-08-01

Food regulations require that tree nuts and derived ingredients are included on food labels in order to help individuals with IgE-mediated allergies to avoid them. However, there is no consensus regarding which tree nut species should be included in this definition and specified on food labels. Allergen detection methods used for monitoring foods target allergen molecules, but it not clear which are the most relevant molecules to choose. A modified population-exposure-comparators-outcome (PECO) approach has been developed to systematically review the evidence regarding (1) which allergenic tree nuts should be included in food allergen labelling lists and (2) which are the clinically relevant allergens which should be used as analytical targets. A search strategy and criteria against which the evidence will be evaluated have been developed. The resulting evidence will be used to rank tree nuts with regards their ability to cause IgE-mediated allergies, and allergen molecules regarding their capacity to elicit an allergic reaction. The results of the systematic review will enable risk assessors and managers to identify tree nut species that should be included in food allergen labelling lists and ensure analytical methods for determination of allergens in foods are targeting appropriate molecules. Copyright © 2017. Published by Elsevier Ltd.

High-Density IgE Recognition of the Major Grass Pollen Allergen Phl p 1 Revealed with Single-Chain IgE Antibody Fragments Obtained by Combinatorial Cloning

PubMed Central

Madritsch, Christoph; Gadermaier, Elisabeth; Roder, Uwe W.; Lupinek, Christian; Valenta, Rudolf; Flicker, Sabine

2015-01-01

The timothy grass pollen allergen Phl p 1 belongs to the group 1 of highly cross-reactive grass pollen allergens with a molecular mass of ~25–30 kDa. Group 1 allergens are recognized by >95% of grass pollen allergic patients. We investigated the IgE recognition of Phl p 1 using allergen-specific IgE-derived single-chain variable Ab fragments (IgE-ScFvs) isolated from a combinatorial library constructed from PBMCs of a grass pollen–allergic patient. IgE-ScFvs reacted with recombinant Phl p 1 and natural group 1 grass pollen allergens. Using synthetic Phl p 1–derived peptides, the binding sites of two ScFvs were mapped to the N terminus of the allergen. In surface plasmon resonance experiments they showed comparable high-affinity binding to Phl p 1 as a complete human IgE-derived Ab recognizing the allergens’ C terminus. In a set of surface plasmon resonance experiments simultaneous allergen recognition of all three binders was demonstrated. Even in the presence of the three binders, allergic patients’ polyclonal IgE reacted with Phl p 1, indicating high-density IgE recognition of the Phl p 1 allergen. Our results show that multiple IgE Abs can bind with high density to Phl p 1, which may explain the high allergenic activity and sensitizing capacity of this allergen. PMID:25637023

Effects of mouse slant and desktop position on muscular and postural stresses, subject preference and performance in women aged 18-40 years.

PubMed

Gaudez, Clarisse; Cail, François

2016-11-01

This study compared muscular and postural stresses, performance and subject preference in women aged 18-40 years using a standard mouse, a vertical mouse and a slanted mouse in three different computer workstation positions. Four tasks were analysed: pointing, pointing-clicking, pointing-clicking-dragging and grasping-pointing the mouse after typing. Flexor digitorum superficialis (FDS) and extensor carpi radialis (ECR) activities were greater using the standard mouse compared to the vertical or slanted mouse. In all cases, the wrist position remained in the comfort zone recommended by standard ISO 11228-3. The vertical mouse was less comfortable and more difficult to use than the other two mice. FDS and ECR activities, shoulder abduction and wrist extension were greater when the mouse was placed next to the keyboard. Performance and subject preference were better with the unrestricted mouse positioning on the desktop. Grasping the mouse after typing was the task that caused the greatest stress. Practitioner Summary: In women, the slanted mouse and the unrestricted mouse positioning on the desktop provide a good blend of stresses, performance and preference. Unrestricted mouse positioning requires no keyboard, which is rare in practice. Placing the mouse in front of the keyboard, rather than next to it, reduced the physical load.

Endogenous allergens and compositional analysis in the allergenicity assessment of genetically modified plants.

PubMed

Fernandez, A; Mills, E N C; Lovik, M; Spoek, A; Germini, A; Mikalsen, A; Wal, J M

2013-12-01

Allergenicity assessment of genetically modified (GM) plants is one of the key pillars in the safety assessment process of these products. As part of this evaluation, one of the concerns is to assess that unintended effects (e.g. over-expression of endogenous allergens) relevant for the food safety have not occurred due to the genetic modification. Novel technologies are now available and could be used as complementary and/or alternative methods to those based on human sera for the assessment of endogenous allergenicity. In view of these developments and as a step forward in the allergenicity assessment of GM plants, it is recommended that known endogenous allergens are included in the compositional analysis as additional parameters to be measured. Copyright © 2013 Elsevier Ltd. All rights reserved.

Respiratory Allergens from Furred Mammals: Environmental and Occupational Exposure

PubMed Central

Raulf, Monika

2017-01-01

Furry mammals kept as pets, farm and laboratory animals are important allergen sources. The prevalence of sensitization to furred mammals appears to be increasing worldwide. Several mammalian allergens from diverse species are well characterized with regard to their molecular structure and immunogenicity, and some are already available for component-resolved allergy diagnostics. The distribution of various mammalian allergens has been extensively studied during the past few decades. Animal allergens were found to be ubiquitous in the human environment, even in places where no animals reside, with concentrations differing considerably between locations and geographical regions. This review presents an overview of identified mammalian respiratory allergens classified according to protein families, and compiles the results of allergen exposure assessment studies conducted in different public and occupational environments. PMID:29056697

Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides lacking allergen-specific T cell epitopes reduces Bet v 1-specific T cell responses via blocking antibodies in a murine model for birch pollen allergy.

PubMed

Linhart, B; Narayanan, M; Focke-Tejkl, M; Wrba, F; Vrtala, S; Valenta, R

2014-02-01

Vaccines consisting of allergen-derived peptides lacking IgE reactivity and allergen-specific T cell epitopes bound to allergen-unrelated carrier molecules have been suggested as candidates for allergen-specific immunotherapy. To study whether prophylactic and therapeutic vaccination with carrier-bound peptides from the major birch pollen allergen Bet v 1 lacking allergen-specific T cell epitopes has influence on Bet v 1-specific T cell responses. Three Bet v 1-derived peptides, devoid of Bet v 1-specific T cell epitopes, were coupled to KLH and adsorbed to aluminium hydroxide to obtain a Bet v 1-specific allergy vaccine. Groups of BALB/c mice were immunized with the peptide vaccine before or after sensitization to Bet v 1. Bet v 1- and peptide-specific antibody responses were analysed by ELISA. T cell and cytokine responses to Bet v 1, KLH, and the peptides were studied in proliferation assays. The effects of peptide-specific and allergen-specific antibodies on T cell responses and allergic lung inflammation were studied using specific antibodies. Prophylactic and therapeutic vaccination with carrier-bound Bet v 1 peptides induced a Bet v 1-specific IgG antibody response without priming/boosting of Bet v 1-specific T cells. Prophylactic and therapeutic vaccination of mice with the peptide vaccine induced Bet v 1-specific antibodies which suppressed Bet v 1-specific T cell responses and allergic lung inflammation. Vaccination with carrier-bound allergen-derived peptides lacking allergen-specific T cell epitopes induces allergen-specific IgG antibodies which suppress allergen-specific T cell responses and allergic lung inflammation. © 2013 John Wiley & Sons Ltd.

A mutant of the major apple allergen, Mal d 1, demonstrating hypo-allergenicity in the target organ by double-blind placebo-controlled food challenge.

PubMed

Bolhaar, S T H P; Zuidmeer, L; Ma, Y; Ferreira, F; Bruijnzeel-Koomen, C A F M; Hoffmann-Sommergruber, K; van Ree, R; Knulst, A C

2005-12-01

Allergen-specific immunotherapy for food allergy has been hindered by severe side-effects in the past. Well-characterized hypo-allergenic recombinant food allergens potentially offer a safe solution. To demonstrate hypo-allergenicity of a mutated major food allergen from apple, Mal d 1, in vitro and in vivo. A mutant of the major apple allergen, Mal d 1, was obtained by site-directed mutagenesis exchanging five amino acid residues. Fourteen patients with combined birch pollen-related apple allergy were included in the study. Hypo-allergenicity of the mutant rMal d 1 (rMal d 1mut) compared with rMal d 1 was assessed by in vitro methods, i.e. RAST (inhibition), immunoblotting and basophil histamine release (BHR) and in vivo by skin prick test and double-blind placebo-controlled food challenge (DBPCFC). RAST analysis (n = 14) revealed that IgE reactivity to rMal d 1mut was twofold lower than that of the wild-type molecule (95% confidence interval (CI): 1.7-2.4). RAST inhibition (n = 6) showed a 7.8-fold decrease in IgE-binding potency (95% CI: 3.0-12.6). In contrast to this moderate decrease in IgE-binding potency, the biological activity of rMal d 1mut assessed by SPT and BHR decreased 10-200-fold. Hypo-allergenicity was confirmed by DBPCFC (n = 2) with both recombinant molecules. A moderate decrease in IgE-binding potency translates into a potent inhibition of biological activity. This is the first study that confirms by DBPCFC that a mutated recombinant major food allergen is clinically hypo-allergenic. This paves the way towards safer immunotherapy for the treatment of food-allergic patients.

Depigmented and polymerised house dust mite allergoid: allergen content, induction of IgG4 and clinical response.

PubMed

Gallego, M T; Iraola, V; Himly, M; Robinson, D S; Badiola, C; García-Robaina, J C; Briza, P; Carnés, J

2010-01-01

Polymerised allergenic extracts (allergoids) are commonly used in allergen immunotherapy. Clinical efficacy and safety of these extracts have been demonstrated. Recently, allergen sequences have been identified by mass spectrometry in depigmented and polymerised (Dpg-Pol) extracts. The objectives of this study were to investigate the presence of allergens in Dpg-Pol extracts of house dust mite and to analyze the immunological changes induced by these extracts in asthmatic patients enrolled in a double-blind, placebo-controlled study. Dpg-Pol extracts were manufactured and vaccines with a composition of 50% Dermatophagoides pteronyssinus and 50% D. farinae (100 HEPL/ml) were prepared. Allergen composition was analyzed by mass spectrometry. Patients with asthma and rhinoconjunctivitis were treated in a 1-year, double-blind, placebo-controlled, parallel-group study with 6 up-dosing and monthly maintenance injections. Specific IgE and IgG4 titres to D. pteronyssinus, Der p 1 and Der p 2 were measured in patients' sera using the CAP system and direct ELISA experiments. Sequences from the major allergens Der p 1 and Der p 2 and from other allergens were identified in native and Dpg-Pol extracts. There was a statistically significant increase in specific IgG4, a decrease in the ratio of IgE/IgG4 to D. pteronyssinus and a significant increase in specific IgG4 to Der p 1 and Der p 2 in the patients allotted to active treatment. The detection of allergen sequences suggests preservation of major and minor allergens in Dpg-Pol allergoids from house dust mites. Efficacy in asthma treatment and the increase in specific IgG4 seem to be associated with the presence of major allergens in Dpg-Pol allergen extracts. Copyright (c) 2010 S. Karger AG, Basel.

The allergen Bet v 1 in fractions of ambient air deviates from birch pollen counts.

PubMed

Buters, J T M; Weichenmeier, I; Ochs, S; Pusch, G; Kreyling, W; Boere, A J F; Schober, W; Behrendt, H

2010-07-01

Proof is lacking that pollen count is representative for allergen exposure, also because allergens were found in nonpollen-bearing fractions of ambient air. We monitored simultaneously birch pollen and the major birch pollen allergen Bet v 1 in different size fractions of ambient air from 2004 till 2007 in Munich, Germany. Air was sampled with a ChemVol high-volume cascade impactor equipped with stages for particulate matter (PM)>10 microm, 10 microm>PM>2.5 microm, and 2.5 microm>PM>0.12 microm. Allergen was determined with a Bet v 1-specific ELISA. Pollen count was assessed with a Burkard pollen trap. We also measured the development of allergen in pollen during ripening. About 93 +/- 3% of Bet v 1 was found in the PM > 10 microm fraction, the fraction containing birch pollen. We did not measure any Bet v 1 in 2.5 microm > PM > 0.12 microm. Either in Munich no allergen was in this fraction or the allergen was absorbed to diesel soot particles that also deposit in this fraction. Pollen released 115% more Bet v 1 in 2007 than in 2004. Also within 1 year, the release of allergen from the same amount of pollen varied more than 10-fold between different days. This difference was explained by a rapidly increasing expression of Bet v 1 in pollen in the week just before pollination. Depending on the day the pollen is released during ripening, its potency varies. In general, pollen count and allergen in ambient air follow the same temporal trends. However, because a 10-fold difference can exist in allergen potency of birch pollen, symptoms might be difficult to correlate with pollen counts, but perhaps better with allergen exposure.

Assessing genetically modified crops to minimize the risk of increased food allergy: a review.

PubMed

Goodman, Richard E; Hefle, Susan L; Taylor, Steven L; van Ree, Ronald

2005-06-01

The first genetically modified (GM) crops approved for food use (tomato and soybean) were evaluated for safety by the United States Food and Drug Administration prior to commercial production. Among other factors, those products and all additional GM crops that have been grown commercially have been evaluated for potential increases in allergenic properties using methods that are consistent with the current understanding of food allergens and knowledge regarding the prediction of allergenic activity. Although there have been refinements, the key aspects of the evaluation have not changed. The allergenic properties of the gene donor and the host (recipient) organisms are considered in determining the appropriate testing strategy. The amino acid sequence of the encoded protein is compared to all known allergens to determine whether the protein is a known allergen or is sufficiently similar to any known allergen to indicate an increased probability of allergic cross-reactivity. Stability of the protein in the presence of acid with the stomach protease pepsin is tested as a risk factor for food allergenicity. In vitro or in vivo human IgE binding are tested when appropriate, if the gene donor is an allergen or the sequence of the protein is similar to an allergen. Serum donors and skin test subjects are selected based on their proven allergic responses to the gene donor or to material containing the allergen that was matched in sequence. While some scientists and regulators have suggested using animal models, performing broadly targeted serum IgE testing or extensive pre- or post-market clinical tests, current evidence does not support these tests as being predictive or practical. Based on the evidence to date, the current assessment process has worked well to prevent the unintended introduction of allergens in commercial GM crops.

Component resolution reveals additional major allergens in patients with honeybee venom allergy.

PubMed

Köhler, Julian; Blank, Simon; Müller, Sabine; Bantleon, Frank; Frick, Marcel; Huss-Marp, Johannes; Lidholm, Jonas; Spillner, Edzard; Jakob, Thilo

2014-05-01

Detection of IgE to recombinant Hymenoptera venom allergens has been suggested to improve the diagnostic precision in Hymenoptera venom allergy. However, the frequency of sensitization to the only available recombinant honeybee venom (HBV) allergen, rApi m 1, in patients with HBV allergy is limited, suggesting that additional HBV allergens might be of relevance. We performed an analysis of sensitization profiles of patients with HBV allergy to a panel of HBV allergens. Diagnosis of HBV allergy (n = 144) was based on history, skin test results, and allergen-specific IgE levels to HBV. IgE reactivity to 6 HBV allergens devoid of cross-reactive carbohydrate determinants (CCD) was analyzed by ImmunoCAP. IgE reactivity to rApi m 1, rApi m 2, rApi m 3, nApi m 4, rApi m 5, and rApi m 10 was detected in 72.2%, 47.9%, 50.0%, 22.9%, 58.3%, and 61.8% of the patients with HBV allergy, respectively. Positive results to at least 1 HBV allergen were detected in 94.4%. IgE reactivity to Api m 3, Api m 10, or both was detected in 68.0% and represented the only HBV allergen-specific IgE in 5% of the patients. Limited inhibition of IgE binding by therapeutic HBV and limited induction of Api m 3- and Api m 10-specific IgG4 in patients obtaining immunotherapy supports recent reports on the underrepresentation of these allergens in therapeutic HBV preparations. Analysis of a panel of CCD-free HBV allergens improved diagnostic sensitivity compared with use of rApi m 1 alone, identified additional major allergens, and revealed sensitizations to allergens that have been reported to be absent or underrepresented in therapeutic HBV preparations. Copyright © 2014 The Authors. Published by Mosby, Inc. All rights reserved.

Altering allergenicity of cow's milk by food processing for applications in infant formula.

PubMed

Golkar, Abdolkhalegh; Milani, Jafar M; Vasiljevic, Todor

2018-04-16

Cow's milk-based infant formulas have a long tradition in infant nutrition, although some infants are unable to use them due to presence of several known allergens. Various processing methods have been identified capable of reducing cow's milk protein allergenicity including thermal and non-thermal methods and their combinations. Heat treatment and enzymatic hydrolysis have been in production of hypoallergenic infant formulas. However, modulation of allergenic epitopes depends on the extent of heat treatment applied, which consequently may also reduce a nutritional value of these proteins. In addition, enzymatic hydrolysis may not target allergenic epitopes thus allergenicity may persist; however released peptides may have detrimental impact on taste and functional properties of final products. Modulation of allergenicity of milk proteins appears to require a concerted effort to minimize detrimental effects as clinical studies conducted on commercial hypoallergenic formulas demonstrated persistence of allergic symptoms. This article covers traditional and novel processing methods and their impact on reduction of cow's milk allergenicity in milk-based infant formulas.

Effects of food processing on food allergens.

PubMed

Sathe, Shridhar K; Sharma, Girdhari M

2009-08-01

Food allergies are on the rise in Western countries. With the food allergen labeling requirements in the US and EU, there is an interest in learning how food processing affects food allergens. Numerous foods are processed in different ways at home, in institutional settings, and in industry. Depending on the processing method and the food, partial or complete removal of the offending allergen may be possible as illustrated by reduction of peanut allergen in vitro IgE immunoreactivity upon soaking and blanching treatments. When the allergen is discretely located in a food, one may physically separate and remove it from the food. For example, lye peeling has been reported to produce hypoallergenic peach nectar. Protein denaturation and/or hydrolysis during food processing can be used to produce hypoallergenic products. This paper provides a short overview of basic principles of food processing followed by examples of their effects on food allergen stability. Reviewed literature suggests assessment of processing effects on clinically relevant reactivity of food allergens is warranted.

Greater Real-Life Diagnostic Efficacy of Allergen Molecule-Based Diagnosis for Prescription of Immunotherapy in an Area with Multiple Pollen Exposure.

PubMed

Saltabayeva, Ulbosin; Garib, Victoria; Morenko, Marina; Rosenson, Rafail; Ispayeva, Zhanat; Gatauova, Madina; Zulus, Loreta; Karaulov, Alexander; Gastager, Felix; Valenta, Rudolf

2017-01-01

Allergen molecule-based diagnosis has been suggested to facilitate the identification of disease-causing allergen sources and the prescription of allergen-specific immunotherapy (AIT). The aim of the current study was to compare allergen molecule-based IgE serology with allergen extract-based skin testing for the identification of the disease-causing allergen sources. The study was conducted in an area where patients are exposed to pollen from multiple sources (trees, grasses, and weeds) at the same time to compare the diagnostic efficiency of the 2 forms of diagnosis. Patients from Astana, Kazakhstan, who suffered from pollen-induced allergy (n = 95) were subjected to skin prick testing (SPT) with a local panel of tree pollen, grass pollen, and weed pollen allergen extracts and IgE antibodies specific for marker allergen molecules (nArt v 1, nArt v 3, rAmb a 1, rPhl p 1, rPhl p 5, rBet v 1) were measured by ImmunoCAP. Direct and indirect costs for diagnosis based on SPT and marker allergen-based IgE serology as well as direct costs for immunotherapy depending on SPT and serological test results were calculated. The costs for SPT-based diagnosis per patient were lower than the costs for allergen molecule-based IgE serology. However, allergen molecule-based serology was more precise in detecting the disease-causing allergen sources. A lower number of immunotherapy treatments (n = 119) was needed according to molecular diagnosis as compared to extract-based diagnosis (n = 275), which considerably reduced the total costs for diagnosis and for a 3-year treatment from EUR 1,112.30 to 521.77 per patient. The results from this real-life study show that SPT is less expensive than allergen molecule-based diagnostic testing, but molecular diagnosis allowed more precise prescription of immunotherapy which substantially reduced treatment costs and combined costs for diagnosis and treatment. © 2017 The Author(s) Published by S. Karger AG, Basel.

Evaluation and integration of existing methods for computational prediction of allergens

PubMed Central

2013-01-01

Background Allergy involves a series of complex reactions and factors that contribute to the development of the disease and triggering of the symptoms, including rhinitis, asthma, atopic eczema, skin sensitivity, even acute and fatal anaphylactic shock. Prediction and evaluation of the potential allergenicity is of importance for safety evaluation of foods and other environment factors. Although several computational approaches for assessing the potential allergenicity of proteins have been developed, their performance and relative merits and shortcomings have not been compared systematically. Results To evaluate and improve the existing methods for allergen prediction, we collected an up-to-date definitive dataset consisting of 989 known allergens and massive putative non-allergens. The three most widely used allergen computational prediction approaches including sequence-, motif- and SVM-based (Support Vector Machine) methods were systematically compared using the defined parameters and we found that SVM-based method outperformed the other two methods with higher accuracy and specificity. The sequence-based method with the criteria defined by FAO/WHO (FAO: Food and Agriculture Organization of the United Nations; WHO: World Health Organization) has higher sensitivity of over 98%, but having a low specificity. The advantage of motif-based method is the ability to visualize the key motif within the allergen. Notably, the performances of the sequence-based method defined by FAO/WHO and motif eliciting strategy could be improved by the optimization of parameters. To facilitate the allergen prediction, we integrated these three methods in a web-based application proAP, which provides the global search of the known allergens and a powerful tool for allergen predication. Flexible parameter setting and batch prediction were also implemented. The proAP can be accessed at http://gmobl.sjtu.edu.cn/proAP/main.html. Conclusions This study comprehensively evaluated sequence-, motif- and SVM-based computational prediction approaches for allergens and optimized their parameters to obtain better performance. These findings may provide helpful guidance for the researchers in allergen-prediction. Furthermore, we integrated these methods into a web application proAP, greatly facilitating users to do customizable allergen search and prediction. PMID:23514097

Evaluation and integration of existing methods for computational prediction of allergens.

PubMed

Wang, Jing; Yu, Yabin; Zhao, Yunan; Zhang, Dabing; Li, Jing

2013-01-01

Allergy involves a series of complex reactions and factors that contribute to the development of the disease and triggering of the symptoms, including rhinitis, asthma, atopic eczema, skin sensitivity, even acute and fatal anaphylactic shock. Prediction and evaluation of the potential allergenicity is of importance for safety evaluation of foods and other environment factors. Although several computational approaches for assessing the potential allergenicity of proteins have been developed, their performance and relative merits and shortcomings have not been compared systematically. To evaluate and improve the existing methods for allergen prediction, we collected an up-to-date definitive dataset consisting of 989 known allergens and massive putative non-allergens. The three most widely used allergen computational prediction approaches including sequence-, motif- and SVM-based (Support Vector Machine) methods were systematically compared using the defined parameters and we found that SVM-based method outperformed the other two methods with higher accuracy and specificity. The sequence-based method with the criteria defined by FAO/WHO (FAO: Food and Agriculture Organization of the United Nations; WHO: World Health Organization) has higher sensitivity of over 98%, but having a low specificity. The advantage of motif-based method is the ability to visualize the key motif within the allergen. Notably, the performances of the sequence-based method defined by FAO/WHO and motif eliciting strategy could be improved by the optimization of parameters. To facilitate the allergen prediction, we integrated these three methods in a web-based application proAP, which provides the global search of the known allergens and a powerful tool for allergen predication. Flexible parameter setting and batch prediction were also implemented. The proAP can be accessed at http://gmobl.sjtu.edu.cn/proAP/main.html. This study comprehensively evaluated sequence-, motif- and SVM-based computational prediction approaches for allergens and optimized their parameters to obtain better performance. These findings may provide helpful guidance for the researchers in allergen-prediction. Furthermore, we integrated these methods into a web application proAP, greatly facilitating users to do customizable allergen search and prediction.

Analysis of calcium-induced conformational changes in calcium-binding allergens and quantitative determination of their IgE binding properties.

PubMed

Parody, Nuria; Fuertes, Miguel Angel; Alonso, Carlos; Pico de Coaña, Yago

2013-01-01

The polcalcin family is one of the most epidemiologically relevant families of calcium-binding allergens. Polcalcins are potent plant allergens that contain one or several EF-hand motifs and their allergenicity is primarily associated with the Ca(2+)-bound form of the protein. Conformation, stability, as well as IgE recognition of calcium-binding allergens greatly depend on the presence of protein-bound calcium ions. We describe a protocol that uses three techniques (SDS-PAGE, circular dichroism spectroscopy, and ELISA) to describe the effects that calcium has on the structural changes in an allergen and its IgE binding properties.

[Biological pollution and allergic diseases].

PubMed

Carrer, P; Moscato, G

2004-01-01

House dust mites, pets, microorganisms such as fungi and bacteria are the main causes of indoor allergens. The diseases correlated to the presence of these allergens are of increasing importance in public health as well as in occupational medicine. Indoor allergens are widespread in residential buildings as well as in public and in office buildings. Surveys conducted in Italian office buildings demonstrated detectable allergen concentrations in most of these buildings. In some cases, the concentrations were higher than the proposed risk threshold for allergenic sensitisation or for the elicitation of symptoms in allergic individuals. The health effects of exposure to indoor allergens mainly include allergic asthma and rhinoconjunctivitis caused by IgE reactions in predisposed subjects. Moreover, exposure to indoor biological agents can cause extrinsic allergic alveolitis or other effects such as the so-called "humidifier fever" due to contaminated humidifiers. Standardized methods for the measurement of indoor allergen levels are available, and may be useful for the diagnosis and treatment of individual allergic patients or for group studies in order to evaluate the relationship between allergen indoor levels and health effects or to assess indoor allergen levels in private or public buildings for preventative purposes.

Recombinant allergy vaccines based on allergen-derived B cell epitopes.

PubMed

Valenta, Rudolf; Campana, Raffaela; Niederberger, Verena

2017-09-01

Immunoglobulin E (IgE)-associated allergy is the most common immunologically-mediated hypersensitivity disease. It affects more than 25% of the population. In IgE-sensitized subjects, allergen encounter can causes a variety of symptoms ranging from hayfever (allergic rhinoconjunctivitis) to asthma, skin inflammation, food allergy and severe life-threatening anaphylactic shock. Allergen-specific immunotherapy (AIT) is based on vaccination with the disease-causing allergens. AIT is an extremely effective, causative and disease-modifying treatment. However, administration of natural allergens can cause severe side effects and the quality of natural allergen extracts limits its application. Research in the field of molecular allergen characterization has allowed deciphering the molecular structures of the disease-causing allergens and it has become possible to engineer novel molecular allergy vaccines which precisely target the mechanisms of the allergic immune response and even appear suitable for prophylactic allergy vaccination. Here we discuss recombinant allergy vaccines which are based on allergen-derived B cell epitopes regarding their molecular and immunological properties and review the results obtained in clinical studies with this new type of allergy vaccines. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

High level expression, purification and physico- and immunochemical characterisation of recombinant Pen a 1: a major allergen of shrimp.

PubMed

Albrecht, Melanie; Alessandri, Stefano; Conti, Amedeo; Reuter, Andreas; Lauer, Iris; Vieths, Stefan; Reese, Gerald

2008-11-01

Well-characterised and immunologically active recombinant allergens are of eminent importance for improvement of diagnostic tools and immunotherapy of allergic diseases. The use of recombinant allergens has several advantages such as the more precise quantification of the active substance compared to allergen extracts and the reduced risk of contamination with other allergenic proteins compared to purified natural allergens. Optimised standard protocols for expression and purification and a detailed physico-chemical characterisation of such recombinant allergens are necessary to ensure consistent quality and comparability of results obtained with recombinant material. In this study the major allergen Pen a 1 of brown shrimp (Penaeus aztecus) was expressed in E. coli and purified in two steps by immobilised metal chelate-affinity chromatography (IMAC) and size-exclusion chromatography. Identity and purity were verified with N-terminal sequencing and peptide mass fingerprinting. Circular dichroism and NMR-spectroscopy indicated an alpha-helical flexible structure of rPen a 1 which is in accordance with the known structure of tropomyosins. Finally, the recombinant allergen proved to be immunologically reactive in IgE Western blot analysis and ELISA. This study provides a protocol for the preparation of recombinant shrimp tropomyosin in standardised quality.

Cross-reactions vs co-sensitization evaluated by in silico motifs and in vitro IgE microarray testing.

PubMed

Pfiffner, P; Stadler, B M; Rasi, C; Scala, E; Mari, A

2012-02-01

Using an in silico allergen clustering method, we have recently shown that allergen extracts are highly cross-reactive. Here we used serological data from a multi-array IgE test based on recombinant or highly purified natural allergens to evaluate whether co-reactions are true cross-reactions or co-sensitizations by allergens with the same motifs. The serum database consisted of 3142 samples, each tested against 103 highly purified natural or recombinant allergens. Cross-reactivity was predicted by an iterative motif-finding algorithm through sequence motifs identified in 2708 known allergens. Allergen proteins containing the same motifs cross-reacted as predicted. However, proteins with identical motifs revealed a hierarchy in the degree of cross-reaction: The more frequent an allergen was positive in the allergic population, the less frequently it was cross-reacting and vice versa. Co-sensitization was analyzed by splitting the dataset into patient groups that were most likely sensitized through geographical occurrence of allergens. Interestingly, most co-reactions are cross-reactions but not co-sensitizations. The observed hierarchy of cross-reactivity may play an important role for the future management of allergic diseases. © 2011 John Wiley & Sons A/S.

Current overview of allergens of plant pathogenesis related protein families.

PubMed

Sinha, Mau; Singh, Rashmi Prabha; Kushwaha, Gajraj Singh; Iqbal, Naseer; Singh, Avinash; Kaushik, Sanket; Kaur, Punit; Sharma, Sujata; Singh, Tej P

2014-01-01

Pathogenesis related (PR) proteins are one of the major sources of plant derived allergens. These proteins are induced by the plants as a defense response system in stress conditions like microbial and insect infections, wounding, exposure to harsh chemicals, and atmospheric conditions. However, some plant tissues that are more exposed to environmental conditions like UV irradiation and insect or fungal attacks express these proteins constitutively. These proteins are mostly resistant to proteases and most of them show considerable stability at low pH. Many of these plant pathogenesis related proteins are found to act as food allergens, latex allergens, and pollen allergens. Proteins having similar amino acid sequences among the members of PR proteins may be responsible for cross-reactivity among allergens from diverse plants. This review analyzes the different pathogenesis related protein families that have been reported as allergens. Proteins of these families have been characterized in regard to their biological functions, amino acid sequence, and cross-reactivity. The three-dimensional structures of some of these allergens have also been evaluated to elucidate the antigenic determinants of these molecules and to explain the cross-reactivity among the various allergens.

Inhibiting Peanut Allergen Digestion with p-Aminobenzamidine Attached to the Allergens

USDA-ARS?s Scientific Manuscript database

Peanut allergens can be digested into peptide fragments despite being known as resistant proteins. Once absorbed, the peptide fragments from digested allergens could bind to immunoglobulin E (IgE) antibodies and cause an allergic reaction in allergic individuals. To reduce peanut allergy, one approa...

Climate change and our environment: the effect on respiratory and allergic disease.

PubMed

Barne, Charles; Alexis, Neil E; Bernstein, Jonathan A; Cohn, John R; Demain, Jeffrey G; Horner, Elliot; Levetin, Estelle; Nei, Andre; Phipatanakul, Wanda

2013-03-01

Climate change is a constant and ongoing process. It is postulated that human activities have reached a point at which we are producing global climate change. It provides suggestions to help the allergist/environmental physician integrate recommendations about improvements in outdoor and indoor air quality and the likely response to predicted alterations in the earth's environment into his or her patient's treatment plan. It incorporates references retrieved from Pub Med searches for topics, including:climate change, global warming, global climate change, greenhouse gasses, air pollution, particulates, black carbon, soot and sea level, as well as references contributed by the individual authors. Many changes that affect respiratory disease are anticipated.Examples of responses to climate change include energy reduction retrofits in homes that could potentially affect exposure to allergens and irritants, more hot sunny days that increase ozone-related difficulties, and rises in sea level or altered rainfall patterns that increase exposure to damp indoor environments.Climate changes can also affect ecosystems, manifested as the appearance of stinging and biting arthropods in new areas.Higher ambient carbon dioxide concentrations, warmer temperatures, and changes in floristic zones could potentially increase exposure to ragweed and other outdoor allergens,whereas green practices such as composting can increase allergen and irritant exposure. Finally, increased energy costs may resultin urban crowding and human source pollution, leading to changes in patterns of infectious respiratory illnesses. Improved governmental controls on airborne pollutants could lead to cleaner air and reduced respiratory diseases but will meet strong opposition because of their effect on business productivity. The allergy community must therefore adapt, as physician and research scientists always have, by anticipating the needs of patients and by adopting practices and research methods to meet changing environmental conditions.

ALLERGENIC RELATIONSHIP OF THE POLLENS OF DWARF AND GIANT RAGWEED TO SEVERAL OF THEIR BOTANIC RELATIVES.

PubMed

Simon, F A

1943-02-01

Thirty-eight of forty patients, allergic to the pollen of dwarf and giant ragweed, were found to be allergic also to the pollen of botanically related species. There was definite variation in the degree of reactivity to the various pollens in different patients. One additional patient reacted to dwarf ragweed but not to giant ragweed or to four other composites. Antibody neutralization studies in six cases indicated that (a) in four cases dwarf ragweed could have been the only sensitizing allergen. (b) In one case either dwarf or giant ragweed could have been the only sensitizing allergen. (c) In one case cosmos plus either of the ragweeds or some undetermined pollen could have been the sensitizing allergen, (d) In none of the six cases studied could cosmos, sunflower, goldenrod, or dandelion have been the only sensitizing allergens. The evidence presented supports the following concepts: (1) Hypersensitiveness of this type develops as the result of allergenic stimulation. (2) The pollens of the ragweeds and their botanic relatives contain, in addition to species-specific allergens, multiple common allergenic determinants which vary in their distribution among related species. (3) A person exposed simultaneously to a group of allergens may become sensitized to certain members of the group and not to others, while another person, exposed to the same group of allergens, may become sensitized to different members of the group.

Abnormal IgG4 antibody response to aeroallergens in allergic patients.

PubMed

Jeannin, P; Delneste, Y; Tillie-Leblond, I; Wallaert, B; carlier, A; Pestel, J; Tonnel, A B

1994-01-01

Various studies have suggested the involvement of immunoglobulin G4 (IgG4) antibodies (Ab) in the physiopathology of allergic disorders. Recently, an abnormal IgG4 Ab production in response to immunization has been reported in some atopic patients. Thus, in order to evidence in allergic patients, a potential abnormal IgG4 Ab response to aeroallergens following natural exposure, we compared, in 34 patients sensitive to Dermatophagoides pteronyssinus and in 16 healthy subjects, the IgG4 Ab response to D. pteronyssinus, grass pollen and cat dander, using a solid-phase radioimmunoassay. Since some patients were also sensitive to grass pollen and/or to cat dander, we analyzed, in all patients, the IgG4 Ab responses both towards the allergen(s) they were sensitive to (sensitizing allergen) or not (unrelated allergen). The results showed that 90% of the patients produced levels of antisensitizing allergen(s) IgG4 Ab significantly higher than the controls; this IgG4 Ab response was correlated with the corresponding specific IgE Ab level. In addition, among these patients, around 40% presented high levels of IgG4 Ab to the unrelated allergen(s). Thus, in allergic patients, while specific IgE Ab define the nature of the sensitizing allergen, the presence of IgG4 Ab directed against various allergens seems in relation with an abnormal isotype regulation associated with atopic disorders.

Studies on `allergoids' prepared from naturally occurring allergens

PubMed Central

Marsh, D. G.; Lichtenstein, L. M.; Campbell, D. H.

1970-01-01

The highly purified major allergenic component of rye grass pollen (Group I) was used to investigate the possibility of destroying selectively the allergenic properties of an antigen, while largely retaining its original immunizing capacities. The allergen was treated under mild conditions with formalin alone or formalin plus a reactive low molecular weight additive. Certain derivatives (allergoids) showed well over 99 per cent reduction in allergenicity, determined by the histamine released from allergic human leucocytes in vitro, but were still able to combine with rabbit antibody against native antigen. Furthermore, the allergoids stimulated production (in guinea-pigs) of appreciable amounts of antibody able to inhibit native allergen-mediated human allergic histamine release in vitro and to cross-react with native antigen by PCA tests in normal guinea-pigs. Residual allergenicity and cross-immunogenicity (by the inhibition assay) of the different formalinized derivatives varied appreciably according to the additive used in formalinization, but the cross-reactivities of the different preparations in quantitative precipitin analysis against rabbit anti-native antigen serum were similar. The residual allergenicities of individual derivatives varied by up to 1000-fold in different cell preparations, suggesting a heterogeneity of allergenic determinants. Allergoid derivatives showed no hapten-like activity in that they were unable to inhibit allergen-mediated histamine release from leucocytes. The theoretical and practical application of allergoids is discussed, including their potential usefulness in improving the immunotheraphy of atopic humans. ImagesFIG. 2 PMID:4192674

Bioinformatic analysis for allergenicity assessment of Bacillus thuringiensis Cry proteins expressed in insect-resistant food crops.

PubMed

Randhawa, Gurinder Jit; Singh, Monika; Grover, Monendra

2011-02-01

The novel proteins introduced into the genetically modified (GM) crops need to be evaluated for the potential allergenicity before their introduction into the food chain to address the safety concerns of consumers. At present, there is no single definitive test that can be relied upon to predict allergic response in humans to a new protein; hence a composite approach to allergic response prediction is described in this study. The present study reports on the evaluation of the Cry proteins, encoded by cry1Ac, cry1Ab, cry2Ab, cry1Ca, cry1Fa/cry1Ca hybrid, being expressed in Bt food crops that are under field trials in India, for potential allergenic cross-reactivity using bioinformatics search tools. The sequence identity of amino acids was analyzed using FASTA3 of AllergenOnline version 10.0 and BLASTX of NCBI Entrez to identify any potential sequence matches to allergen proteins. As a step further in the detection of allergens, an independent database of domains in the allergens available in the AllergenOnline database was also developed. The results indicated no significant alignment and similarity of Cry proteins at domain level with any of the known allergens revealing that there is no potential risk of allergenic cross-reactivity. Copyright © 2010 Elsevier Ltd. All rights reserved.

Levels of house dust mite allergen in cars.

PubMed

Mason, Howard J; Smith, Ian; Anua, Siti Marwanis; Tagiyeva, Nargiz; Semple, Sean; Devereux, Graham

2015-09-01

This small study investigated house dust mite (HDM) allergen levels in cars and their owners' homes in north-east Scotland. Dust samples from twelve households and cars were collected in a standardised manner. The dust samples were extracted and measured for the Dermatophagoides group 2 allergens (Der p 2 and Der f 2) and total soluble protein. Allergen levels at homes tended to be higher than in the cars, but not significantly. However, they significantly correlated with paired car dust samples expressed either per unit weight of dust or soluble protein (rho=0.657; p=0.02 and 0.769; p=0.003, respectively). This points to house-to-car allergen transfer, with the car allergen levels largely reflecting levels in the owner's home. Car HDM allergen levels were lower than those reported in Brazil and the USA. Twenty-five percent of the houses and none of the cars had allergen levels in dust greater than 2000 ng g(-1). This value is often quoted as a threshold for the risk of sensitisation, although a number of studies report increased risk of sensitisation at lower levels. This small study does not allow for characterisation of the distribution of HDM allergen in vehicles in this geographic area, or of the likely levels in other warmer and more humid areas of the UK. Cars and other vehicles are an under-investigated micro-environment for exposure to allergenic material.

Molecular diagnosis and immunotherapy.

PubMed

Sastre, Joaquín; Sastre-Ibañez, Marina

2016-12-01

To describe recent insights into how molecular diagnosis can improve indication and selection of suitable allergens for specific immunotherapy and increase the safety of this therapy. As specific allergen immunotherapy targets specific allergens, identification of the disease-eliciting allergen is a prerequisite for accurate prescription of treatment. In areas of complex sensitization to aeroallergens or in cases of hymenoptera venom allergy, the use of molecular diagnosis has demonstrated that it may lead to a change in indication and selection of allergens for immunotherapy in a large proportion of patients when compared with diagnosis based on skin prick testing and/or specific IgE determination with commercial extracts. These changes in immunotherapy prescription aided by molecular diagnosis have been demonstrated to be cost-effective in some scenarios. Certain patterns of sensitization to grass or olive pollen and bee allergens may identify patients with higher risk of adverse reaction during immunotherapy. Molecular diagnosis, when used with other tools and patients' clinical records, can help clinicians better to select the most appropriate patients and allergens for specific immunotherapy and, in some cases, predict the risk of adverse reactions. The pattern of sensitization to allergens could potentially predict the efficacy of allergen immunotherapy provided that these immunotherapy products contain a sufficient amount of these allergens. Nevertheless, multiplex assay remains a third-level approach, not to be used as screening method in current practice.

Kissing selectively decreases allergen-specific IgE production in atopic patients.

PubMed

Kimata, H

2006-05-01

Stress enhanced allergic skin wheal responses and allergen-specific IgE production. In contrast, mothers' kissing caused relaxation in infants, and kissing by lovers or spouses to atopic patients reduced allergic skin wheal responses. I studied the effect of kissing on production of allergen-specific IgE and cytokines in atopic patients. Twenty-four patients with mild atopic eczema and 24 patients with mild allergic rhinitis kissed with lovers or spouses freely for 30 min while listening to soft music. Just before and immediately after kissing, blood mononuclear cells were separated cultured for allergen, and production of allergen-specific immunoglobulin and cytokine was measured. Kissing selectively decreased allergen-specific IgE production with skewing cytokine pattern toward Th1 type. Kissing may alleviate allergic symptoms by decrease in allergen-specific IgE production.

A Targeted LC-MS/MS Method for the Simultaneous Detection and Quantitation of Egg, Milk, and Peanut Allergens in Sugar Cookies.

PubMed

Boo, Chelsea C; Parker, Christine H; Jackson, Lauren S

2018-01-01

Food allergy is a growing public health concern, with many individuals reporting allergies to multiple food sources. Compliance with food labeling regulations and prevention of inadvertent cross-contact in manufacturing requires the use of reliable methods for the detection and quantitation of allergens in processed foods. In this work, a novel liquid chromatography-tandem mass spectrometry multiple-reaction monitoring method for multiallergen detection and quantitation of egg, milk, and peanut was developed and evaluated in an allergen-incurred baked sugar cookie matrix. A systematic evaluation of method parameters, including sample extraction, concentration, and digestion, were optimized for candidate allergen peptide markers. The optimized method enabled the reliable detection and quantitation of egg, milk, and peanut allergens in sugar cookies, with allergen concentrations as low as 5 ppm allergen-incurred ingredient.

A survey of food allergen control practices in the U.S. food industry.

PubMed

Gendel, Steven M; Khan, Nazleen; Yajnik, Monali

2013-02-01

Despite awareness of the importance of food allergy as a public health issue, recalls and adverse reactions linked to undeclared allergens in foods continue to occur with high frequency. To reduce the overall incidence of such problems and to ensure that food-allergic consumers have the information they need to prevent adverse reactions, it is important to understand which allergen control practices are currently used by the food industry. Therefore, the U.S. Food and Drug Administration carried out directed inspections of registered food facilities in 2010 to obtain a broader understanding of industry allergen control practices in the United States. The results of these inspections show that allergen awareness and the use of allergen controls have increased greatly in the last decade, but that small facilities lag in implementing allergen controls.

Technological Innovations for High-Throughput Approaches to In Vitro Allergy Diagnosis.

PubMed

Chapman, Martin D; Wuenschmann, Sabina; King, Eva; Pomés, Anna

2015-07-01

Allergy diagnostics is being transformed by the advent of in vitro IgE testing using purified allergen molecules, combined with multiplex technology and biosensors, to deliver discriminating, sensitive, and high-throughput molecular diagnostics at the point of care. Essential elements of IgE molecular diagnostics are purified natural or recombinant allergens with defined purity and IgE reactivity, planar or bead-based multiplex systems to enable IgE to multiple allergens to be measured simultaneously, and, most recently, nanotechnology-based biosensors that facilitate rapid reaction rates and delivery of test results via mobile devices. Molecular diagnostics relies on measurement of IgE to purified allergens, the "active ingredients" of allergenic extracts. Typically, this involves measuring IgE to multiple allergens which is facilitated by multiplex technology and biosensors. The technology differentiates between clinically significant cross-reactive allergens (which could not be deduced by conventional IgE assays using allergenic extracts) and provides better diagnostic outcomes. Purified allergens are manufactured under good laboratory practice and validated using protein chemistry, mass spectrometry, and IgE antibody binding. Recently, multiple allergens (from dog) were expressed as a single molecule with high diagnostic efficacy. Challenges faced by molecular allergy diagnostic companies include generation of large panels of purified allergens with known diagnostic efficacy, access to flexible and robust array or sensor technology, and, importantly, access to well-defined serum panels form allergic patients for product development and validation. Innovations in IgE molecular diagnostics are rapidly being brought to market and will strengthen allergy testing at the point of care.

Airborne cat allergen reduction in classrooms that use special school clothing or ban pet ownership.

PubMed

Karlsson, Anne-Sophie; Andersson, Berith; Renström, Anne; Svedmyr, Jan; Larsson, Kjell; Borres, Magnus P

2004-06-01

Allergens from furred animals are brought to school mainly via clothing of pet owners. Asthmatic children allergic to cat have more symptoms when attending a class with many cat owners, and some schools allocate specific resources to allergen avoidance measures. The aim of the current study was to evaluate the effect of school clothing or pet owner-free classes compared with control classes on airborne cat allergen levels and to investigate attitudes and allergic symptoms among the children. Allergen measurements were performed prospectively in 2 classes with school clothing, 1 class of children who were not pet owners, and 3 control classes during a 6-week period in 2 consecutive years. Portable pumps and petri dishes were used for collection of airborne cat allergen, and a roller was used for sampling on children's clothes. Cat allergen (Fel d 1) was analyzed with enzyme-linked immunoassay and immunostaining. Both years, questionnaires were administered to the children. We found 4-fold to 6-fold lower airborne cat allergen levels in intervention classes compared with control classes. Levels of cat allergen were 3-fold higher on clothing of cat owners than of children without cats in control classes. Pet ownership ban seemed less accepted than school clothing as an intervention measure. For the first time, it has been shown that levels of airborne cat allergen can be reduced by allergen avoidance measures at school by using school clothing or pet ownership ban, and that both measures are equally efficient. The clinical effect of these interventions remains to be evaluated.

Airway responsiveness to mannitol 24 h after allergen challenge in atopic asthmatics.

PubMed

Davis, B E; Amakye, D O; Cockcroft, D W

2015-06-01

Airway responsiveness to indirect stimuli correlates positively with airway inflammation. In atopic asthmatics, allergen inhalation is associated with an influx of inflammatory cells and increased responsiveness to the direct-acting stimuli methacholine at 3 and 24 h after exposure. We have shown mannitol responsiveness decreases 3 h after allergen inhalation. The current investigation assessed mannitol responsiveness 24 h after allergen challenge. Eleven mild atopic asthmatics completed allergen challenges on two separate occasions. In random order, methacholine or mannitol challenges were performed 24 h pre- and post-allergen challenge. Levels of fractional exhaled nitric oxide were also measured. Allergen challenge increased airway responsiveness to methacholine 24 h postchallenge; the geometric mean (95% CI) methacholine PC20 decreased from 5.9 mg/ml (1.8-19.4) to 2.2 mg/ml (0.81-5.89); P = 0.01. This coincided with a significant increase (P = 0.02) in FeNO levels. Conversely, allergen challenge decreased airway responsiveness to mannitol; geometric mean (95% CI) dose-response ratio was significantly higher after allergen exposure (57 mg/% FEV1 fall [27-121] to 147 mg/% FEV1 fall [57-379]; P = 0.03), and FeNO levels were not significantly increased (P = 0.054). Allergen-induced changes in airway responsiveness to direct and indirect stimuli are markedly different. The loss in responsiveness to mannitol is likely not explainable by a refractory state. The effect(s) of allergen exposure on airway responsiveness to indirect-acting stimuli require further investigation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Roflumilast attenuates allergen-induced inflammation in mild asthmatic subjects.

PubMed

Gauvreau, Gail M; Boulet, Louis-Philippe; Schmid-Wirlitsch, Christine; Côté, Johanne; Duong, Mylinh; Killian, Kieran J; Milot, Joanne; Deschesnes, Francine; Strinich, Tara; Watson, Richard M; Bredenbröker, Dirk; O'Byrne, Paul M

2011-10-26

Phosphodiesterase 4 (PDE4) inhibitors increase intracellular cyclic adenosine monophosphate (cAMP), leading to regulation of inflammatory cell functions. Roflumilast is a potent and targeted PDE4 inhibitor. The objective of this study was to evaluate the effects of roflumilast on bronchoconstriction, airway hyperresponsiveness (AHR), and airway inflammation in mild asthmatic patients undergoing allergen inhalation challenge. 25 subjects with mild allergic asthma were randomized to oral roflumilast 500 mcg or placebo, once daily for 14 days in a double-blind, placebo-controlled, crossover study. Allergen challenge was performed on Day 14, and FEV1 was measured until 7 h post challenge. Methacholine challenge was performed on Days 1 (pre-dose), 13 (24 h pre-allergen), and 15 (24 h post-allergen), and sputum induction was performed on Days 1, 13, 14 (7 h post-allergen), and 15. Roflumilast inhibited the allergen-induced late phase response compared to placebo; maximum % fall in FEV1 (p = 0.02) and the area under the curve (p = 0.01). Roflumilast had a more impressive effect inhibiting allergen-induced sputum eosinophils, neutrophils, and eosinophil cationic protein (ECP) at 7 h post-allergen (all p = 0.02), and sputum neutrophils (p = 0.04), ECP (p = 0.02), neutrophil elastase (p = 0.0001) and AHR (p = 0.004) at 24 h post-allergen. This study demonstrates a protective effect of roflumilast on allergen-induced airway inflammation. The observed attenuation of sputum eosinophils and neutrophils demonstrates the anti-inflammatory properties of PDE4 inhibition and supports the roles of both cell types in the development of late phase bronchoconstriction and AHR. ClinicalTrials.gov: NCT01365533.

Allergenicity and cross-reactivity of booklice (Liposcelis bostrichophila): a common household insect pest in Japan.

PubMed

Fukutomi, Yuma; Kawakami, Yuji; Taniguchi, Masami; Saito, Akemi; Fukuda, Azumi; Yasueda, Hiroshi; Nakazawa, Takuya; Hasegawa, Maki; Nakamura, Hiroyuki; Akiyama, Kazuo

2012-01-01

Booklice (Liposcelis bostrichophila) are a common household insect pest distributed worldwide. Particularly in Japan, they infest 'tatami' mats and are the most frequently detected insect among all detectable insects, present at a frequency of about 90% in dust samples. Although it has been hypothesized that they are an important indoor allergen, studies on their allergenicity have been limited. To clarify the allergenicity of booklice and the cross-reactivity of this insect allergen with allergens of other insects, patients sensitized to booklice were identified from 185 Japanese adults with allergic asthma using skin tests and IgE-ELISA. IgE-inhibition analysis, immunoblotting and immunoblotting-inhibition analysis were performed using sera from these patients. Allergenic proteins contributing to specific sensitization to booklice were identified by two-dimensional electrophoresis and two-dimensional immunoblotting. The booklouse-specific IgE antibody was detected in sera from 41 patients (22% of studied patients). IgE inhibition analysis revealed that IgE reactivity to the booklouse allergen in the sera from one third of booklouse-sensitized patients was not inhibited by preincubation with extracts from any other environmental insects in this study. Immunoblotting identified a 26-kD protein from booklouse extract as the allergenic protein contributing to specific sensitization to booklice. The amino acid sequence of peptide fragments of this protein showed no homology to those of previously described allergenic proteins, indicating that this protein is a new allergen. Sensitization to booklice was relatively common and specific sensitization to this insect not related to insect panallergy was indicated in this population. Copyright © 2011 S. Karger AG, Basel.

Clinical relevance is associated with allergen-specific wheal size in skin prick testing

PubMed Central

Haahtela, T; Burbach, G J; Bachert, C; Bindslev-Jensen, C; Bonini, S; Bousquet, J; Bousquet-Rouanet, L; Bousquet, P J; Bresciani, M; Bruno, A; Canonica, G W; Darsow, U; Demoly, P; Durham, S R; Fokkens, W J; Giavi, S; Gjomarkaj, M; Gramiccioni, C; Kowalski, M L; Losonczy, G; Orosz, M; Papadopoulos, N G; Stingl, G; Todo-Bom, A; von Mutius, E; Köhli, A; Wöhrl, S; Järvenpää, S; Kautiainen, H; Petman, L; Selroos, O; Zuberbier, T; Heinzerling, L M

2014-01-01

Background Within a large prospective study, the Global Asthma and Allergy European Network (GA2LEN) has collected skin prick test (SPT) data throughout Europe to make recommendations for SPT in clinical settings. Objective To improve clinical interpretation of SPT results for inhalant allergens by providing quantitative decision points. Methods The GA2LEN SPT study with 3068 valid data sets was used to investigate the relationship between SPT results and patient-reported clinical relevance for each of the 18 inhalant allergens as well as SPT wheal size and physician-diagnosed allergy (rhinitis, asthma, atopic dermatitis, food allergy). The effects of age, gender, and geographical area on SPT results were assessed. For each allergen, the wheal size in mm with an 80% positive predictive value (PPV) for being clinically relevant was calculated. Results Depending on the allergen, from 40% (blatella) to 87–89% (grass, mites) of the positive SPT reactions (wheal size ≥ 3 mm) were associated with patient-reported clinical symptoms when exposed to the respective allergen. The risk of allergic symptoms increased significantly with larger wheal sizes for 17 of the 18 allergens tested. Children with positive SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10 mm depending on the allergen. Conclusion These ‘reading keys’ for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form with the standard allergens including mm decision points for each allergen is offered for clinical use. PMID:24283409

Clinical relevance is associated with allergen-specific wheal size in skin prick testing.

PubMed

Haahtela, T; Burbach, G J; Bachert, C; Bindslev-Jensen, C; Bonini, S; Bousquet, J; Bousquet-Rouanet, L; Bousquet, P J; Bresciani, M; Bruno, A; Canonica, G W; Darsow, U; Demoly, P; Durham, S R; Fokkens, W J; Giavi, S; Gjomarkaj, M; Gramiccioni, C; Kowalski, M L; Losonczy, G; Orosz, M; Papadopoulos, N G; Stingl, G; Todo-Bom, A; von Mutius, E; Köhli, A; Wöhrl, S; Järvenpää, S; Kautiainen, H; Petman, L; Selroos, O; Zuberbier, T; Heinzerling, L M

2014-03-01

Within a large prospective study, the Global Asthma and Allergy European Network (GA(2) LEN) has collected skin prick test (SPT) data throughout Europe to make recommendations for SPT in clinical settings. To improve clinical interpretation of SPT results for inhalant allergens by providing quantitative decision points. The GA(2) LEN SPT study with 3068 valid data sets was used to investigate the relationship between SPT results and patient-reported clinical relevance for each of the 18 inhalant allergens as well as SPT wheal size and physician-diagnosed allergy (rhinitis, asthma, atopic dermatitis, food allergy). The effects of age, gender, and geographical area on SPT results were assessed. For each allergen, the wheal size in mm with an 80% positive predictive value (PPV) for being clinically relevant was calculated. Depending on the allergen, from 40% (blatella) to 87-89% (grass, mites) of the positive SPT reactions (wheal size ≥ 3 mm) were associated with patient-reported clinical symptoms when exposed to the respective allergen. The risk of allergic symptoms increased significantly with larger wheal sizes for 17 of the 18 allergens tested. Children with positive SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10 mm depending on the allergen. These 'reading keys' for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form with the standard allergens including mm decision points for each allergen is offered for clinical use. © 2013 The Authors. Clinical & Experimental Allergy published by John Wiley & Sons Ltd.

Consumer Preferences for Written and Oral Information about Allergens When Eating Out.

PubMed

Begen, Fiona M; Barnett, Julie; Payne, Ros; Roy, Debbie; Gowland, M Hazel; Lucas, Jane S

2016-01-01

Avoiding food allergens when eating outside the home presents particular difficulties for food allergic (FA) and intolerant (FI) consumers and a lack of allergen information in restaurants and takeaways causes unnecessary restrictions. Across Europe, legislation effective from December 2014, aims to improve allergen information by requiring providers of non-prepacked foods to supply information related to allergen content within their foods. Using in-depth interviews with 60 FA/FI adults and 15 parents/carers of FA/FI children, we aimed to identify FA/FI consumers' preferences for written and/or verbal allergen information when eating out or ordering takeaway food. A complex and dynamic set of preferences and practices for written and verbal allergen information was identified. Overwhelmingly, written information was favoured in the first instance, but credible personal/verbal communication was highly valued and essential to a good eating out experience. Adequate written information facilitated implicit trust in subsequent verbal information. Where written information was limited, FA/FIs depended on social cues to assess the reliability of verbal information resources, and defaulted to tried and tested allergen avoidance strategies when these were deemed unreliable. Understanding the subtle negotiations and difficulties encountered by FA/FIs when eating out can serve as a guide for legislators and food providers; by encouraging provision of clear written and verbal allergen information, and training of proactive, allergen-aware staff. This, in tandem with legal requirements for allergen information provision, paves the way for FA/FIs to feel more confident in eating out choices; and to experience improved eating out experiences.

Genetic and environmental factors affecting allergen-related gene expression in apple fruit (Malus domestica L. Borkh).

PubMed

Botton, Alessandro; Lezzer, Paolo; Dorigoni, Alberto; Barcaccia, Gianni; Ruperti, Benedetto; Ramina, Angelo

2008-08-13

Freshly consumed apples can cause allergic reactions because of the presence of four classes of allergens, namely, Mal d 1, Mal d 2, Mal d 3, and Mal d 4, and their cross-reactivity with sensitizing allergens of other species. Knowledge of environmental and endogenous factors affecting the allergenic potential of apples would provide important information to apple breeders, growers, and consumers for the selection of hypoallergenic genotypes, the adoption of agronomical practices decreasing the allergenic potential, and the consumption of fruits with reduced amount of allergens. In the present research, expression studies were performed by means of real-time PCR for all the known allergen-encoding genes in apple. Fruit samples were collected from 15 apple varieties and from fruits of three different trials, set up to assess the effect of shadowing, elevation, storage, and water stress on the expression of allergen genes. Principal components analysis (PCA) was performed for the classification of varieties according to gene expression values, pointing out that the cultivars Fuji and Brina were two good hypoallergenic candidates. Shadowing, elevation, and storage significantly affected the transcription of the allergen-encoding genes, whereas water stress slightly influenced the expression of only two genes, in spite of the dramatic effect on both fruit size and vegetative growth of the trees. In particular, shadowing may represent an important cultural practice aimed at reducing apple cortex allergenicity. Moreover, elevation and storage may be combined to reduce the allergenic potential of apple fruits. The possible implications of the results for breeders, growers, and consumers are discussed critically.

Consumer Preferences for Written and Oral Information about Allergens When Eating Out

PubMed Central

Begen, Fiona M.; Barnett, Julie; Payne, Ros; Roy, Debbie; Gowland, M. Hazel; Lucas, Jane S.

2016-01-01

Background Avoiding food allergens when eating outside the home presents particular difficulties for food allergic (FA) and intolerant (FI) consumers and a lack of allergen information in restaurants and takeaways causes unnecessary restrictions. Across Europe, legislation effective from December 2014, aims to improve allergen information by requiring providers of non-prepacked foods to supply information related to allergen content within their foods. Methods Using in-depth interviews with 60 FA/FI adults and 15 parents/carers of FA/FI children, we aimed to identify FA/FI consumers’ preferences for written and/or verbal allergen information when eating out or ordering takeaway food. Results A complex and dynamic set of preferences and practices for written and verbal allergen information was identified. Overwhelmingly, written information was favoured in the first instance, but credible personal/verbal communication was highly valued and essential to a good eating out experience. Adequate written information facilitated implicit trust in subsequent verbal information. Where written information was limited, FA/FIs depended on social cues to assess the reliability of verbal information resources, and defaulted to tried and tested allergen avoidance strategies when these were deemed unreliable. Conclusion Understanding the subtle negotiations and difficulties encountered by FA/FIs when eating out can serve as a guide for legislators and food providers; by encouraging provision of clear written and verbal allergen information, and training of proactive, allergen-aware staff. This, in tandem with legal requirements for allergen information provision, paves the way for FA/FIs to feel more confident in eating out choices; and to experience improved eating out experiences. PMID:27223698

Allergens in household dust and serological indicators of atopy and sensitization in Detroit children with history--based eivdence of asthma

EPA Science Inventory

BACKGROUND: Home exposure to allergens is an important factor in the development of sensitization and subsequent exacerbations of allergic asthma. We investigated linkages among allergen exposure, immunological measurements, and asthma by examining (1) reservoir dust allergen lev...

Adsorption of Cashew Allergens to Acid-Etched Zinc Metal Particles

USDA-ARS?s Scientific Manuscript database

Galvanized metal surfaces are approved by the FDA for use in many food processing steps. Food allergens can cause severe reactions even in very small amounts, and surfaces contaminated with allergens could pose a serious threat. The binding of cashew allergens to zinc particles was evaluated. Whi...

New tree nut allergens

USDA-ARS?s Scientific Manuscript database

The 7S vicilin and 11S legumin seed storage globulins belong to the cupin protein superfamily and are major food allergens in many of the “big eight” food allergen groups. Korean pine vicilin and pecan vicilin are thus predicted to be food allergens. Recombinant vicilins were expressed in E. coli an...

Protease-Activated Receptor-2 Activation Contributes to House Dust Mite-Induced IgE Responses in Mice

PubMed Central

Post, Sijranke; Heijink, Irene H.; Petersen, Arjen H.; de Bruin, Harold G.; van Oosterhout, Antoon J. M.; Nawijn, Martijn C.

2014-01-01

Aeroallergens such as house dust mite (HDM), cockroach, and grass or tree pollen are innocuous substances that can induce allergic sensitization upon inhalation. The serine proteases present in these allergens are thought to activate the protease-activated receptor (PAR)-2, on the airway epithelium, thereby potentially inducing allergic sensitization at the expense of inhalation tolerance. We hypothesized that the proteolytic activity of allergens may play an important factor in the allergenicity to house dust mite and is essential to overcome airway tolerance. Here, we aimed to investigate the role of PAR-2 activation in allergic sensitization and HDM-induced allergic airway inflammation. In our study, Par-2 deficient mice were treated with two different HDM extracts containing high and low serine protease activities twice a week for a period of 5 weeks. We determined airway inflammation through quantification of percentages of mononuclear cells, eosinophils and neutrophils in the bronchial alveolar lavage fluid and measured total IgE and HDM-specific IgE and IgG1 levels in serum. Furthermore, Th2 and pro-inflammatory cytokines including IL-5, IL-13, Eotaxin-1, IL-17, KC, Chemokine (C-C motif) ligand 17 (CCL17) and thymic stromal lymphopoietin (TSLP), were measured in lung tissue homogenates. We observed that independent of the serine protease content, HDM was able to induce elevated levels of eosinophils and neutrophils in the airways of both wild-type (WT) and Par-2 deficient mice. Furthermore, we show that induction of pro-inflammatory cytokines by HDM exposure is independent of Par-2 activation. In contrast, serine protease activity of HDM does contribute to enhanced levels of total IgE, but not HDM-specific IgE. We conclude that, while Par-2 activation contributes to the development of IgE responses, it is largely dispensable for the HDM-induced induction of pro-inflammatory cytokines and airway inflammation in an experimental mouse model of HDM-driven allergic airway disease. PMID:24651123

Novel allergic asthma model demonstrates ST2-dependent dendritic cell targeting by cypress pollen.

PubMed

Gabriele, Lucia; Schiavoni, Giovanna; Mattei, Fabrizio; Sanchez, Massimo; Sestili, Paola; Butteroni, Cinzia; Businaro, Rita; Mirchandani, Ananda; Niedbala, Wanda; Liew, Foo Y; Afferni, Claudia

2013-09-01

Cypress pollen causes respiratory syndromes with different grades of severity, including asthma. IL-33, its receptor ST2, and dendritic cells (DCs) have been implicated in human respiratory allergy. We sought to define a new mouse model of allergy to cypress pollen that recapitulates clinical parameters in allergic patients and to evaluate the implications of DCs and the IL-33/ST2 pathway in this pathology. BALB/c mice, either wild-type or ST2 deficient (ST2(-/-)), were sensitized and challenged with the Cupressus arizonica major allergen nCup a 1. Local and systemic allergic responses were evaluated. Pulmonary cells were characterized by means of flow cytometry. DCs were stimulated with nCup a 1 and tested for their biological response to IL-33 in coculture assays. nCup a 1 causes a respiratory syndrome closely resembling human pollinosis in BALB/c mice. nCup a 1-treated mice exhibit the hallmarks of allergic pathology associated with pulmonary infiltration of eosinophils, T cells, and DCs and a dominant TH2-type immune response. IL-33 levels were increased in lungs and sera of nCup a 1-treated mice and in subjects with cypress allergy. The allergen-specific reaction was markedly reduced in ST2(-/-) mice, which showed fewer infiltrating eosinophils, T cells, and DCs in the lungs. Finally, stimulation of DCs with nCup a 1 resulted in ST2 upregulation that endowed DCs with increased ability to respond to IL-33-mediated differentiation of IL-5- and IL-13-producing CD4 T cells. Our findings define a novel preclinical model of allergy to cypress pollen and provide the first evidence of a functionally relevant linkage between pollen allergens and TH2-polarizing activity by DCs through IL-33/ST2. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

The central zone has increased 68Ga-PSMA-11 uptake: "Mickey Mouse ears" can be hot on 68Ga-PSMA-11 PET.

PubMed

Pizzuto, Daniele A; Müller, Julian; Mühlematter, Urs; Rupp, Niels J; Töpfer, Antonia; Mortezavi, Ashkan; Nagel, Hannes; Kranzbühler, Benedikt; Eberli, Daniel; Burger, Irene A

2018-03-09

Given the good correlation between PSMA expression and intraglandular tumour aggressiveness based on immunohistochemistry, there is increasing interest in 68 Ga-PSMA-11 PET/MRI for staging prostate cancer (PCA). Therefore, accurate knowledge of prostate anatomy as well as normal distribution of PSMA within the prostate gland is becoming essential. The aim of this study was to investigate the physiological intraprostatic distribution of 68 Ga-PSMA-11. We retrospectively analysed all patients who underwent a staging 68 Ga-PSMA-11 PET/MRI scan between June 2016 and January 2018 for high-risk PCA, underwent radical prostatectomy in our institution, and gave written consent for further data analysis. In each patient, standardized volumes of interest (VOIs) were placed bilaterally in the central, transition and peripheral zones within the zonal anatomy according to T2 weighted sequences in the axial and coronal planes. VOIs were only placed if they were safely within healthy tissue without spillover from the PCA. SUV max and SUV mean were determined and their differences among the regions were assessed using the Wilcoxon signed-ranks test. Of 283 consecutive patients scanned with 68 Ga-PSMA-11 PET/MR, 31 were analysed. A total of 133 VOIs were placed, 46 in the central zone, 41 in the transition zone and 46 in the peripheral zone. Differences in SUV max between the central zone (mean 3.9 ± 0.58) and transition zone (mean 3.2 ± 0.59) and between the central zone and peripheral zone (mean 2.7 ± 0.54) were statistically significant (both p < 0.001). Our results suggest that higher 68 Ga-PSMA-11 accumulation in the central zone than in the transition and peripheral zones is normal, and leads to a pattern resembling "Mickey Mouse ears" on 68 Ga-PSMA-11 PET. This pattern could be helpful in avoiding false-positive interpretations of PET scans.

Evaluation of reduced allergenicity of irradiated peanut extract using splenocytes from peanut-sensitized mice

NASA Astrophysics Data System (ADS)

Oh, Sejo; Jang, Da-In; Lee, Ju-Woon; Kim, Jae-Hun; Byun, Myung-Woo; Lee, Soo-Young

2009-07-01

Peanut (PN) allergy is one of the most serious forms of IgE-mediated food hypersensitivity. Gamma irradiation has been widely used for the preservation of food. The results of our previous studies showed that the IgE-binding capacity to several antigens were profoundly reduced after gamma irradiation. In this study, we evaluated the changes of allergenecity and cytokine production profiles after exposure of irradiated PN extract in a PN-allergy mouse model. Mice were sensitized to PN extract by intragastric administration on days 0, 1, 2, and 7, and then challenged on day 21. Four weeks later, we evaluated the cytokine production patterns and proliferation responses of splenocytes that were stimulated with intact PN extract, compared to 10 and 50 kGy irradiated PN extract. When the cells were stimulated with 10 kGy of irradiated PN extract, a higher level of production of IFN-γ and IL-10 cytokines was observed. However, stimulation with 50 kGy of irradiated PN extract resulted in a higher level of production of only IFN-γ cytokines. In addition, the Th1/Th2 ratio increased in response to treatment with gamma-irradiated PNs. The results of this study show that the allergenicity of PN extracts could be reduced by gamma irradiation which caused downregulation of Th2 lymphocyte activity in the PN-sensitized mice.

The Translational Repressor T-cell Intracellular Antigen-1 (TIA-1) is a Key Modulator of Th2 and Th17 Responses Driving Pulmonary Inflammation Induced by Exposure to House Dust Mite

PubMed Central

Simarro, Maria; Giannattasio, Giorgio; Xing, Wei; Lundequist, Emma-Maria; Stewart, Samantha; Stevens, Richard L.; Orduña, Antonio; Boyce, Joshua A.; Anderson, Paul J.

2012-01-01

T-cell Intracellular Antigen-1 (TIA-1) is a translational repressor that dampens the production of proinflammatory cytokines and enzymes. In this study we investigated the role of TIA-1 in a mouse model of pulmonary inflammation induced by exposure to the allergenic extract (Df) of the house dust mite Dermatophagoides farinae. When intranasally challenged with a low dose of Df, mice lacking TIA-1 protein (Tia-1−/−) showed more severe airway and tissue eosinophilia, infiltration of lung bronchovascular bundles, and goblet cell metaplasia than wild-type littermates. Tia-1−/− mice also had higher levels of Df-specific IgE and IgG1 in serum and ex vivo restimulated Tia-1−/− lymph node cells and splenocytes transcribed and released more Th2/Th17 cytokines. To evaluate the site of action of TIA-1, we studied the response to Df in bone marrow chimeras. These experiments revealed that TIA-1 acts on both hematopoietic and non-hematopoietic cells to dampen pulmonary inflammation. Our results identify TIA-1 as a negative regulator of allergen-mediated pulmonary inflammation in vivo. Thus, TIA-1 might be an important player in the pathogenesis of bronchial asthma. PMID:22525013

The translational repressor T-cell intracellular antigen-1 (TIA-1) is a key modulator of Th2 and Th17 responses driving pulmonary inflammation induced by exposure to house dust mite.

PubMed

Simarro, Maria; Giannattasio, Giorgio; Xing, Wei; Lundequist, Emma-Maria; Stewart, Samantha; Stevens, Richard L; Orduña, Antonio; Boyce, Joshua A; Anderson, Paul J

2012-08-30

T-cell intracellular antigen-1 (TIA-1) is a translational repressor that dampens the production of proinflammatory cytokines and enzymes. In this study we investigated the role of TIA-1 in a mouse model of pulmonary inflammation induced by exposure to the allergenic extract (Df) of the house dust mite Dermatophagoides farinae. When intranasally challenged with a low dose of Df, mice lacking TIA-1 protein (Tia-1(-/-)) showed more severe airway and tissue eosinophilia, infiltration of lung bronchovascular bundles, and goblet cell metaplasia than wild-type littermates. Tia-1(-/-) mice also had higher levels of Df-specific IgE and IgG(1) in serum and ex vivo restimulated Tia-1(-/-) lymph node cells and splenocytes transcribed and released more Th2/Th17 cytokines. To evaluate the site of action of TIA-1, we studied the response to Df in bone marrow chimeras. These experiments revealed that TIA-1 acts on both hematopoietic and non-hematopoietic cells to dampen pulmonary inflammation. Our results identify TIA-1 as a negative regulator of allergen-mediated pulmonary inflammation in vivo. Thus, TIA-1 might be an important player in the pathogenesis of bronchial asthma. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of Weatherization Combined With Community Health Worker In-Home Education on Asthma Control

PubMed Central

Dixon, Sherry; Gregory, Joel; Philby, Miriam; Jacobs, David E.; Krieger, James

2014-01-01

Objectives. We assessed the benefits of adding weatherization-plus-health interventions to an in-home, community health worker (CHW) education program on asthma control. Methods. We used a quasi-experimental design to compare study group homes (n = 34) receiving CHW education and weatherization-plus-health structural interventions with historical comparison group homes (n = 68) receiving only education. Data were collected in King County, Washington, from October 2009 to September 2010. Results. Over the 1-year study period, the percentage of study group children with not-well-controlled or very poorly controlled asthma decreased more than the comparison group percentage (100% to 28.8% vs 100% to 51.6%; P = .04). Study group caregiver quality-of-life improvements exceeded comparison group improvements (P = .002) by 0.7 units, a clinically important difference. The decrease in study home asthma triggers (evidence of mold, water damage, pests, smoking) was marginally greater than the comparison group decrease (P = .089). Except for mouse allergen, the percentage of study group allergen floor dust samples at or above the detection limit decreased, although most reductions were not statistically significant. Conclusions. Combining weatherization and healthy home interventions (e.g., improved ventilation, moisture and mold reduction, carpet replacement, and plumbing repairs) with CHW asthma education significantly improves childhood asthma control. PMID:24228661

Identification of IgE-binding proteins from Lepidoglyphus destructor and production of monoclonal antibodies to a major allergen.

PubMed

Ventas, P; Carreira, J; Polo, F

1991-08-01

The allergen composition of one of the most important storage mites, Lepidoglyphus destructor, has been studied by immunodetection after SDS-PAGE with individual patient sera. An allergenic polypeptide of 14 kDa was identified with 95% of the sera. This major allergen was isolated in the supernatant of 60% ammonium sulfate salt precipitation of the whole extract, which was subsequently used to immunize BALB/c mice so as to produce monoclonal antibodies. Four mAbs recognizing molecules with IgE-binding ability were obtained. The specificity of the mAbs was assayed against different allergenic extracts, and the molecules recognized by them were characterized by immunoblotting. Two mAbs (Le5B5 and Le9E4) were directed to the 14-kDa allergen; the other two to several proteins of lesser allergenic significance.

Indoor Allergens and Allergic Respiratory Disease

PubMed Central

Chapman, Martin D.; Wünschmann, Sabina

2016-01-01

Purpose of review The purpose of this review is to evaluate the most recent findings on indoor allergens and their impact on allergic diseases. Recent findings Indoor allergens are present inside buildings (home, work environment, school), and given the chronic nature of the exposures, indoor allergies tend to be associated with the development of asthma. The most common indoor allergens are derived from dust mites, cockroaches, mammals (including wild rodents and pets), and fungi. The advent of molecular biology and proteomics has led to the identification, cloning, and expression of new indoor allergens, which have facilitated research to elucidate their role in allergic diseases. This review is an update on new allergens and their molecular features, together with the most recent reports on their avoidance for allergy prevention and their use for diagnosis and treatment. Summary Research progress on indoor allergens will result in the development of new diagnostic tools and design of coherent strategies for immunotherapy. PMID:27184001

Degradation and removal of soybean allergen in Japanese soy sauce.

PubMed

Magishi, Norihiro; Yuikawa, Naoya; Kobayashi, Makio; Taniuchi, Shoichiro

2017-08-01

Soy sauce is a traditional fermented seasoning of Japan and is available throughout the world. The two main raw ingredients of soy sauce are soybean and wheat, both of which are established food allergens. The present study examined the degradation and removal of soybean allergens in soy sauce by immunoblotting with anti‑soybean protein antibody from rabbit and sera from two children with soybean allergy. It was demonstrated that soybean allergens were gradually degraded during the fermentation process, but were not completely degraded in raw soy sauce. During the processes of heat‑treatment and filtration, the soluble soybean allergens in raw soy sauce were denatured to insoluble allergens by heat‑treatment and subsequently completely removed from soy sauce by filtration. Therefore, to reduce the allergenicity of soy sauce, heat‑treatment and filtration are very important processes in addition to the enzymatic degradation during the fermentation of soy sauce.

Identification of the allergen Psi c 2 from the basidiomycete Psilocybe cubensis as a fungal cyclophilin.

PubMed

Horner, W E; Reese, G; Lehrer, S B

1995-01-01

Basidiospores are a prevalent and frequent cause of respiratory allergies, yet their allergens remain poorly defined; thus, we have attempted a molecular characterization of representative basidiomycete allergens. A Psilocybe cubensis mycelial cDNA library was immunoscreened with patient serum. A clone was isolated that expressed a 23-kD recombinant allergen as a fusion protein and inhibited a 16-kD band (Psi c 2) in immunoprints of P. cubenis extract, indicating antigenic identity. Sequence (cDNA) analysis of the clone indicates homology with cyclophilin and the deduced amino acid sequence of Psi c 2 showed 78% identity and 4% similarity with the amino acid sequence of Schizosaccharomyces pombe cyclophilin. This recombinant allergen is a useful model for epitope analysis of basidiospore allergens and fungal allergen cross-reactivity, and may provide an improved reagent for basidiospore allergy diagnosis and treatment.

Allergen-specific immunotherapy: from therapeutic vaccines to prophylactic approaches

PubMed Central

Valenta, R.; Campana, R.; Marth, K.; van Hage, M.

2015-01-01

Immunoglobulin E-mediated allergies affect more than 25% of the population. Allergen exposure induces a variety of symptoms in allergic patients, which include rhinitis, conjunctivitis, asthma, dermatitis, food allergy and life-threatening systemic anaphylaxis. At present, allergen-specific immunotherapy (SIT), which is based on the administration of the disease-causing allergens, is the only disease-modifying treatment for allergy. Current therapeutic allergy vaccines are still prepared from relatively poorly defined allergen extracts. However, with the availability of the structures of the most common allergen molecules, it has become possible to produce well-defined recombinant and synthetic allergy vaccines that allow specific targeting of the mechanisms of allergic disease. Here we provide a summary of the development and mechanisms of SIT, and then review new forms of therapeutic vaccines that are based on recombinant and synthetic molecules. Finally, we discuss possible allergen-specific strategies for prevention of allergic disease. PMID:22640224

New Trends in Food Allergens Detection: Toward Biosensing Strategies.

PubMed

Alves, Rita C; Barroso, M Fátima; González-García, María Begoña; Oliveira, M Beatriz P P; Delerue-Matos, Cristina

2016-10-25

Food allergens are a real threat to sensitized individuals. Although food labeling is crucial to provide information to consumers with food allergies, accidental exposure to allergenic proteins may result from undeclared allergenic substances by means of food adulteration, fraud or uncontrolled cross-contamination. Allergens detection in foodstuffs can be a very hard task, due to their presence usually in trace amounts, together with the natural interference of the matrix. Methods for allergens analysis can be mainly divided in two large groups: the immunological assays and the DNA-based ones. Mass spectrometry has also been used as a confirmatory tool. Recently, biosensors appeared as innovative, sensitive, selective, environmentally friendly, cheaper and fast techniques (especially when automated and/or miniaturized), able to effectively replace the classical methodologies. In this review, we present the advances in the field of food allergens detection toward the biosensing strategies and discuss the challenges and future perspectives of this technology.

Effect of oleic acid on the allergenic properties of peanut and cashew allergens

USDA-ARS?s Scientific Manuscript database

Oleic acid is the major fatty acid in peanuts and cashews. There is limited information about its effect on peanut and cashew allergens during heating. The objective was to determine if heat treatment with oleic acid changes the allergenic properties of these nut proteins. Peanut and cashew protein...

Diversity of allergen exposure: implications for the efficacy of environmental control.

PubMed

Segundo, Gesmar Rodrigues Silva; Sopelete, Mônica Camargo; Terra, Sílvia Azevedo; Pereira, Fernando Lourenço; Justino, Caroline Morais; Silva, Deise Aparecida de Oliveira; Taketomi, Ernesto Akio

2009-01-01

The prevalence of allergic diseases such as asthma, rhinitis, allergic conjunctivitis and atopic dermatitis has increased in the last decades. The relationship between allergen exposure, atopic sensitization and development of allergic diseases is widely described in the literature. To evaluate measures for reducing allergen exposure as part of the treatment of allergic diseases. An analysis was made of previous studies on allergen exposure done with a similar methodology in the central region of Brazil; the study included homes, hotels, cinemas, cars, taxis, buses and scholar transportation. High levels of Der p 1 and Der f 1 mite allergens were found in a large proportion of the sample in most of the environments included in those studies; there were higher levels of pet allergens in cars and school transportation vehicles. The diversity of allergen exposure demonstrates the need for education about allergic diseases for patients and their families, as well as measures of reducing allergens in homes. This should be part of a global strategy of the management of allergic diseases, given that individuals live in society, not only in their houses.

Identification of major allergens in watermelon.

PubMed

Pastor, Carlos; Cuesta-Herranz, Javier; Cases, Barbara; Pérez-Gordo, Marina; Figueredo, Elena; de las Heras, Manuel; Vivanco, Fernando

2009-01-01

Watermelon is a worldwide consumed Cucurbitaceae fruit that can elicit allergic reactions. However, the major allergens of watermelon are not known. The aim of this study is to identify and characterize major allergens in watermelon. Twenty-three patients allergic to watermelon took part in the study. The diagnosis was based on a history of symptoms and positive skin prick-prick tests to watermelon, confirmed by positive open oral challenge testing to watermelon pulp. Allergenic components were detected by SDS-PAGE and immunoblotting. Molecular characterization of IgE-binding bands was performed by N-terminal amino acid sequencing and mass spectrometry. Allergens were purified combining several chromatographic steps. Several IgE binding bands (8-120 kDa) were detected in watermelon extract. Three major allergens were identified as malate dehydrogenase (36 kDa), triose phosphate isomerase (28 kDa) and profilin (13 kDa). Purified allergens individually inhibited IgE binding to the whole watermelon extract. All in all these results indicate that malate dehydrogenase, triose phosphate isomerase and profilin are major allergens involved in watermelon allergy. Copyright (C) 2009 S. Karger AG, Basel.

The influence of air conditioning, humidity, temperature and other household characteristics on mite allergen concentrations in the northeastern United States.

PubMed

van Strien, R T; Gehring, U; Belanger, K; Triche, E; Gent, J; Bracken, M B; Leaderer, B P

2004-06-01

Information about the influence of housing and occupant characteristics on mite allergen concentrations is crucial to determine which methods could be used to decrease exposure of susceptible subjects. To identify housing and occupant characteristics that are associated with mite allergen concentrations in house dust collected from living rooms and mattresses. We collected dust samples from 750 homes in the northeastern US. The influence of various characteristics on concentrations of mite allergens (Der p 1 and Der f 1) was studied using multiple linear regression analysis. Some characteristics, like absence of air conditioners, the presence of mold or mildew, and a lower temperature were consistently associated with higher concentrations of both mite allergens in dust from all sampling locations. However, none of these factors changed Der p 1 or Der f 1 concentrations by more than a factor of 2. People of white ethnic background had roughly two times higher mite allergen concentrations, while family income, family size, and education level only marginally influenced mite allergen concentrations. Various housing characteristics have some influence on mite allergen concentrations, and could possibly be used to decrease exposure of susceptible subjects. However, only a limited percentage of the variation in mite allergen concentrations was explained by these characteristics.

The SAFE project: 'plant food allergies: field to table strategies for reducing their incidence in Europe' an EC-funded study.

PubMed

Hoffmann-Sommergruber, K

2005-04-01

The true prevalence of food allergy as an IgE mediated reaction is still under discussion. Using apple as a model allergen source a multidisciplinary consortium worked together at developing various strategies for reducing the incidence of fruit allergies in an EC-funded project. Patient allergen profiles were established using in vitro and in vivo tests with respect to geographic area and mild or severe symptoms. Apple allergens (Mal d 1-Mal d 4) were characterised, variants identified, cloned and sequenced. These individual allergens were used to increase the sensitivity and specificity of diagnosis. Furthermore, they provided better prognosis of disease severity. RT-PCR and ELISA were developed for determining the allergen specific mRNA and expressed allergenic protein in a large number of apple cultivars. Similarly, changes in allergen characteristics from harvest through storage to processing and the impact of agronomic practices were investigated. Allergen genes were mapped on a molecular linkage map of apple. The biological function of Mal d 1 was studied using the RNA interference strategy. Finally, consumer attitudes in Northern, Central and Southern Europe were gauged on the acceptability of low allergen cultivars or a GMO and its impact on product quality.

Assessment of endogenous allergenicity of genetically modified plants exemplified by soybean - Where do we stand?

PubMed

Selb, R; Wal, J M; Moreno, F J; Lovik, M; Mills, C; Hoffmann-Sommergruber, K; Fernandez, A

2017-03-01

According to EU regulation, genetically modified (GM) plants considered to be allergenic have to be assessed concerning their endogenous allergens before placement on the EU market, in line with the international standards described in Codex Alimentarius. Under such premises, a quantitative relevant increase in allergens might occur in GM plants as an unintended effect compared with conventionally produced crops, which could pose a risk to consumers. Currently, data showing a connection between dose and allergic sensitisation are scarce since the pathophysiological mechanisms of sensitisation are insufficiently understood. In contrast, data on population dose-distribution relationships acquired by oral food challenge are available showing a connection between quantity of allergenic protein consumed and the population of allergic individuals experiencing reactions. Soybean is currently the only recognised allergenic GM food by law for which EFSA has received applications and was therefore taken as an example for defining an assessment strategy. Identification of potential allergens, methodology for quantification as well as risk assessment considerations, are discussed. A strategy is proposed for the identification, assessment and evaluation of potential hazards/risks concerning endogenous allergenicity in food derived from plants developed by biotechnology. This approach could be expanded to other allergenic foods in the future, whenever required. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lymphocyte blastogenic responses to inciting food allergens in dogs with food hypersensitivity.

PubMed

Ishida, Rinei; Masuda, Kenichi; Kurata, Keigo; Ohno, Koichi; Tsujimoto, Hajime

2004-01-01

Lymphocyte blastogenic responses against food allergens in dogs with food hypersensitivity were evaluated in this study. Eleven dogs with food hypersensitivity, based on food elimination and oral food provocation tests and allergic responses to food allergens, were examined by various tests such as intradermal testing, antigen-specific IgE testing, and lymphocyte blastogenic responses. The number and kinds of food allergens identified as positive by these tests were compared with the offending food allergens that were found in an oral food provocation test. In 9 (82%) of the 11 dogs with food hypersensitivity, there was close agreement for positive allergens between the results of lymphocyte blastogenic responses and oral food provocation test; however, there was little agreement for intradermal and IgE testing of the positive allergens with those of the oral food provocation test (11% and 31%, respectively). In the 9 dogs, the stimulation indices of lymphocyte blastogenic responses increased to 2.0-10.1 upon food provocation but decreased significantly to 0.7-1.4 upon feeding the elimination diet until clinical signs disappeared. These results indicate that lymphocyte blastogenic responses may fluctuate because of exposure to offending food allergens in dogs with food hypersensitivity. Lymphocytes reactive to food allergens may play an important role in the pathogenesis of food hypersensitivity in dogs.

[High-sensitive detection of multiple allergenic proteins in infant food with high-resolution mass spectrometry].

PubMed

Wu, Ci; Chen, Xi; Liu, Jianhui; Zhang, Xiaolin; Xue, Weifeng; Liang, Zhen; Liu, Mengyao; Cui, Yan; Huang, Daliang; Zhang, Lihua

2017-10-08

A novel method of the simultaneous detection of multiple kinds of allergenic proteins in infant food with parallel reaction monitoring (PRM) mode using liquid chromatography-tandem mass spectrometry (LC-MS/MS) was established. In this method, unique peptides with good stability and high sensibility were used to quantify the corresponding allergenic proteins. Furthermore, multiple kinds of allergenic proteins are inspected simultaneously with high sensitivity. In addition, such method was successfully used for the detection of multiple allergenic proteins in infant food. As for the sample preparation for infant food, compared with the traditional acetone precipitation strategy, the protein extraction efficiency and capacity of resisting disturbance are both higher with in-situ filter-aided sample pretreatment (i-FASP) method. All allergenic proteins gave a good linear response with the correlation coefficients ( R 2 ) ≥ 0.99, and the largest concentration range of the allergenic proteins could be four orders of magnitude, and the lowest detection limit was 0.028 mg/L, which was better than that reported in references. Finally, the method was conveniently used to detect the allergens from four imported infant food real samples. All the results demonstrate that this novel strategy is of great significance for providing a rapid and reliable analytical technique for allergen proteomics.

Oleaceae cross-reactions as potential pollinosis cause in urban areas.

PubMed

Vara, A; Fernández-González, M; Aira, M J; Rodríguez-Rajo, F J

2016-01-15

It is worth noting the allergological problems induced by a not accurate design of the ornamental vegetation in the parks and streets of the cities. Usually, in the Oleaceae family, only the olive pollen is considered an important aeroallergen but other species of the family could be an important source of airborne pollen allergens. Pollen from Fraxinus, Olea and Ligustrum and its main aeroallergens were sampled in the atmosphere of an urban area in North-Western Spain during 2011. The allergen bioaerosol content was quantified by using specific 2-site ELISA and Ole e 1 antibodies. The Fra e 1 and Lig v 1 allergens were detected by means Ole e 1 antibodies. This fact demonstrates the cross-reactivity between the main allergens of Fraxinus, Olea and Ligustrum, plants widely species used as ornamental in the cities. Therefore, the urban allergenic people sensitized to Olea pollen could present allergenic reactions during the winter (due to ash pollen allergens), the spring (caused by olive pollen allergens) and the early summer (triggered by the privet flowering). As a consequence, sensitivity to the pollen of one species may favour development of sensitivity to all three species as consequence of the priming effect. The combination of pollen count and the allergen quantification must be assessed in the epidemiologic study of allergic respiratory diseases.

Comprehensive in silico allergenicity assessment of novel protein engineered chimeric Cry proteins for safe deployment in crops.

PubMed

Rathinam, Maniraj; Singh, Shweta; Pattanayak, Debasis; Sreevathsa, Rohini

2017-08-02

Development of chimeric Cry toxins by protein engineering of known and validated proteins is imperative for enhancing the efficacy and broadening the insecticidal spectrum of these genes. Expression of novel Cry proteins in food crops has however created apprehensions with respect to the safety aspects. To clarify this, premarket evaluation consisting of an array of analyses to evaluate the unintended effects is a prerequisite to provide safety assurance to the consumers. Additionally, series of bioinformatic tools as in silico aids are being used to evaluate the likely allergenic reaction of the proteins based on sequence and epitope similarity with known allergens. In the present study, chimeric Cry toxins developed through protein engineering were evaluated for allergenic potential using various in silico algorithms. Major emphasis was on the validation of allergenic potential on three aspects of paramount significance viz., sequence-based homology between allergenic proteins, validation of conformational epitopes towards identification of food allergens and physico-chemical properties of amino acids. Additionally, in vitro analysis pertaining to heat stability of two of the eight chimeric proteins and pepsin digestibility further demonstrated the non-allergenic potential of these chimeric toxins. The study revealed for the first time an all-encompassing evaluation that the recombinant Cry proteins did not show any potential similarity with any known allergens with respect to the parameters generally considered for a protein to be designated as an allergen. These novel chimeric proteins hence can be considered safe to be introgressed into plants.

Assessment of airborne soy-hull allergen (Gly m 1) in the Port of Ancona, Italy.

PubMed

Antonicelli, L; Ruello, M L; Monsalve, R I; González, R; Fava, G; Bonifazi, F

2010-10-01

Epidemic asthma outbreaks are potentially a very high-risk medical situation in seaport towns where large volumes of soybean are loaded and unloaded Airborne allergen assessment plays a pivotal role in evaluating the resulting environmental pollution. The aim of this study was to measure the airborne Gly m 1 allergen level in the seaport of Ancona in order assess the soybean-specific allergenic risk for the city. Allergen and PM10 were evaluated at progressive distances from the port area. Allergen analysis was performed by monoclonal antibody-based immunoassay on the sampled filters. Daily meteorological data were obtained from the local meteorological station. For estimating the assimilative capacity of the atmosphere, an approach based on dispersive ventilation coefficient was tried. The allergen concentrations detected were low (range = 0.4-171 ng/m3). A decreasing gradient of the airborne allergen from the unloading area (22.1 +/- 41.2 ng/m3) to the control area (0.6 +/- 0.7 ng/m3) was detected. The concentration of the airborne Gly m 1 was not coupled with the presence of the soy-carrying ships in the port. A statistically significant relationship between airborne allergen, PM10 and local meteorological parameters quantifies the association with the atmospheric condition. Airborne Gly m 1 is part of the atmospheric dust of Ancona. The low level of this allergen seems consistent with the absence of asthma epidemic outbreak.

Polyphenol-rich pomegranate juice reduces IgE binding to cashew nut allergens.

PubMed

Li, Yichen; Mattison, Christopher P

2018-03-01

Food allergy negatively impacts quality of life and can be life-threatening. Cashew nuts can cause severe reactions in very small amounts, and they are included in a group of foods most commonly responsible for causing food allergy. Polyphenols and polyphenol-rich juices have been demonstrated to complex with peanut allergens. Here, the interaction between cashew nut allergens and polyphenol-rich juices is evaluated biochemically and immunologically. Various juices, including pomegranate (POM), blueberry (BB), and concord grape (CG) juices, were evaluated for polyphenol content and formation of polyphenol-cashew allergen complexes. Among the various juices studied, POM juice showed a greater capacity to form complexes with cashew proteins. Dynamic light scattering (DLS) demonstrated a sharp increase in cashew protein extract particle size to around 3580 nm, and fewer cashew proteins were resolved by electrophoresis after treatment with POM juice. Immunoassays demonstrated reduced IgG and IgE binding to cashew allergens due to allergen precipitation by POM juice. These observations support the formation of complexes between polyphenol and cashew proteins that can prevent antibody recognition of cashew allergens through allergen precipitation. POM juice treatment of cashew extract effectively reduces antibody binding through allergen precipitation, and these findings could be applied to the development of less allergenic cashew nut products and oral immunotherapy. Published 2017. This article is a U.S. Government work and is in the public domain in the USA. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Is there a threshold concentration of cat allergen exposure on respiratory symptoms in adults?

PubMed

Chen, Chih-Mei; Thiering, Elisabeth; Zock, Jan-Paul; Villani, Simona; Olivieri, Mario; Modig, Lars; Jarvis, Deborah; Norbäck, Dan; Verlato, Giuseppe; Heinrich, Joachim

2015-01-01

Cat allergen concentrations higher than 8 μg/g in settled house dust, have been suggested to provoke exacerbation of allergic respiratory symptoms. However, whether the 8 μg/g of indoor cat allergen concentration is indeed the minimal exposure required for triggering the asthma related respiratory symptoms or the development of sensitization has not yet been confirmed. We studied the associations between domestic cat allergen concentrations and allergic symptoms in the European Community Respiratory Health Survey II, with the aim of confirming this suggested threshold. Cat allergen concentrations were measured in the mattress dust of 3003 participants from 22 study centres. Levels of specific immunoglobulin E to cat allergens were measured in serum samples using an immunoassay. Information on allergic symptoms, medication use, home environment and smoking was obtained from a face-to-face interview. Domestic cat allergen concentrations were not associated with allergic/ asthmatic symptoms in the entire study population, nor in the subset sensitized to cat allergen. We also found no association among individuals exposed to concentrations higher than 8 μg/g. However, exposure to medium cat allergen concentrations (0.24-0.63 μg/g) was positively associated with reported asthmatic respiratory symptoms in subjects who have experienced allergic symptoms when near animals. The proposed 8 μg/g threshold of cat allergen concentrations for the exacerbation of allergic/ respiratory symptoms was not confirmed in a general European adult population. Potential biases attributable to avoidance behaviours and an imprecise exposure assessment cannot be excluded.

Factors affecting allergen-specific IgE serum levels in cats

PubMed Central

Belova, S.; Wilhelm, S.; Linek, M.; Beco, L.; Fontaine, J.; Bergvall, K.; Favrot, C.

2012-01-01

Pruritic skin diseases are common in cats and demand rigorous diagnostic workup for finding an underlying etiology. Measurement of a serum allergen-specific IgE in a pruritic cat is often used to make or confirm the diagnosis of a skin hypersensitivity disease, although current evidence suggests that elevated allergen-specific IgE do not always correlate with a clinical disease and vice versa. The aim of the study was to to assess the possible influence of age, deworming status, lifestyle, flea treatment, and gender on allergen-specific IgE levels and to evaluate the reliability of IgE testing in predicting the final diagnosis of a pruritic cat. For this purpose sera of 179 cats with pruritus of different causes and 20 healthy cats were evaluated for allergen-specific IgE against environmental, food and flea allergens using the Fc-epsilon receptor based enzyme-linked immunosorbent assay (ELISA) test. The results of the study showed positive correlation between age, outdoor life style, absence of deworming, absence of flea control measures and levels of allergen-specific IgE. Gender and living area (urban versus rural) did not seem to affect the formation of allergen-specific IgE. According to these findings, evaluating allergen-specific IgE levels, is not a reliable test to diagnose hypersensitivity to food or environmental allergens in cats. On the contrary, this test can be successfully used for diagnosing feline flea bite hypersensitivity. PMID:22754094

Challenges and Path Forward on Mandatory Allergen Labeling and Voluntary Precautionary Allergen Labeling for a Global Company.

PubMed

Yeung, Jupiter; Robert, Marie-Claude

2018-01-01

For food manufacturers, the label on a food package is a tool meant to alert consumers to the presence of specific allergens, allowing consumers to make informed decisions and not unnecessarily limit their food choices. Mandatory allergen labeling is used when the allergen is an intentionally added ingredient, whereas voluntary allergen labeling is used when the presence of the allergen is unintentional and may be in the finished product as a result of cross-contact. In a globalized economy, ensuring food safety is a growing challenge for manufacturers. When ingredients and technologies are sourced worldwide from multiple business partners, complexity rises, which can increase the chance for errors, leading to potential harm. Threshold science, Voluntary Incidental Trace Allergen Labelling (VITAL) reference doses, fit-for-purpose analytical technology, and common sense enable us to optimize allergen management for the benefit of allergic consumers. This is a good strategy because all stakeholders share the common goal of making foods safe and wholesome for all. Herein, we recommend that (1) senior management make science-based thresholds a priority for both regulatory authorities and the food industry; (2) VITAL 2.0 be adopted as a risk assessment and risk management tool for precautionary allergen labeling (PAL); (3) a standardized message for PAL, i.e., "may contain x," be used to make it easily understandable to allergic consumers so they can make informed food choices; and (4) validated fit-for-purpose allergen methods be used to meet analytical needs. This is an opportunity for us to speak with one voice and demonstrate that food safety is not a competitive issue, but a shared responsibility. This approach could significantly improve allergic consumers' lives.

Airborne and food sensitization patterns in children and adults with eosinophilic esophagitis.

PubMed

He, Yu Ting; Christos, Paul J; Reisacher, William R

2018-05-01

The pathogenesis of eosinophilic esophagitis (EoE) is currently unknown, but evidence suggests that allergic sensitization to food and airborne allergens may play a key role. This retrospective study examines the rate of sensitization to both food and airborne allergens in EoE patients, and compares their sensitivity patterns to control groups. We identified 103 patients with a diagnosis of EoE via esophageal eosinophilia (≥15 eosinophils/high-power field [hpf]), who had undergone comprehensive food and/or airborne allergen testing through either skin or in vitro methods. Food and airborne allergen sensitization was defined as positive testing in at least 1 food subgroup (milk, peanut, tree nut, seafood/fish, soy, grain, egg) or airborne subgroup (tree, grass, weed, mite/cockroach, animal, mold), respectively. The same sensitization criterion was applied to allergic rhinitis (AR) patients, with and without a clinical suspicion of food allergy (FA), in order to create control groups. Sensitization in the EoE group to at least 1 subgroup of food allergen and airborne allergen was seen in 77.1% (64/83) and 71.7% (38/53), respectively (p = 0.82). There were significant differences in sensitization between EoE and control groups for tree nut, soy, grain, and egg, but no differences noted in any of the other food or airborne allergen subgroups, even after accounting for age and gender. EoE and control groups had similar airborne allergen sensitization patterns, yet dissimilar food allergen sensitization patterns, suggesting that specific allergens may play a more prominent role in the pathogenesis of EoE. The EoE group had a more uniform distribution pattern for food allergens, compared to controls. © 2018 ARS-AAOA, LLC.

Changes in Atmospheric CO2 Influence the Allergenicity of Aspergillus fumigatus fungal spore

NASA Astrophysics Data System (ADS)

Lang-Yona, N.; Levin, Y.; Dannemoller, K. C.; Yarden, O.; Peccia, J.; Rudich, Y.

2013-12-01

Increased allergic susceptibility has been documented without a comprehensive understanding for its causes. Therefore understanding trends and mechanisms of allergy inducing agents is essential. In this study we investigated whether elevated atmospheric CO2 levels can affect the allergenicity of Aspergillus fumigatus, a common allergenic fungal species. Both direct exposure to changing CO2 levels during fungal growth, and indirect exposure through changes in the C:N ratios in the growth media were inspected. We determined the allergenicity of the spores through two types of immunoassays, accompanied with genes expression analysis, and proteins relative quantification. We show that fungi grown under present day CO2 levels (392 ppm) exhibit 8.5 and 3.5 fold higher allergenicity compared to fungi grown at preindustrial (280 ppm) and double (560 ppm) CO2 levels, respectively. A corresponding trend is observed in the expression of genes encoding for known allergenic proteins and in the major allergen Asp f1 concentrations, possibly due to physiological changes such as respiration rates and the nitrogen content of the fungus, influenced by the CO2 concentrations. Increased carbon and nitrogen levels in the growth medium also lead to a significant increase in the allergenicity, for which we propose two different biological mechanisms. We suggest that climatic changes such as increasing atmospheric CO2 levels and changes in the fungal growth medium may impact the ability of allergenic fungi such as Aspergillus fumigatus to induce allergies. The effect of changing CO2 concentrations on the total allergenicity per 10^7 spores of A. fumigatus (A), the major allergen Asp f1 concentration in ng per 10^7 spores (B), and the gene expression by RT-PCR (C). The error bars represent the standard error of the mean.

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen.

PubMed

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy.

Identification of Aspergillus (A. flavus and A. niger) Allergens and Heterogeneity of Allergic Patients' IgE Response.

PubMed

Vermani, Maansi; Vijayan, Vannan Kandi; Agarwal, Mahendra Kumar

2015-08-01

Aspergillus species (A. flavus and A. niger) are important sources of inhalant allergens. Current diagnostic modalities employ crude Aspergillus extracts which only indicate the source to which the patient has been sensitized, without identifying the number and type of allergens in crude extracts. We report a study on the identification of major and minor allergens of the two common airborne Aspergillus species and heterogeneity of patients' IgE response to them. Skin prick tests were performed on 300 patients of bronchial asthma and/or allergic rhinitis and 20 healthy volunteers. Allergen specific IgE in patients' sera was estimated by enzyme allergosorbent test (EAST). Immunoblots were performed to identify major/minor allergens of Aspergillus extracts and to study heterogeneity of patients'IgE response to them. Positive cutaneous responses were observed in 17% and 14.7% of patients with A. flavus and A. niger extracts, respectively. Corresponding EAST positivity was 69.2% and 68.7%. In immunoblots, 5 allergenic proteins were identified in A. niger extract, major allergens being 49, 55.4 and 81.5 kDa. Twelve proteins bound patients' IgE in A. flavus extract, three being major allergens (13.3, 34 and 37 kDa). The position and slopes of EAST binding and inhibition curves obtained with individual sera varied from patient to patient. The number and molecular weight of IgE-binding proteins in both the Aspergillus extracts varied among patients. These results gave evidence of heterogeneity of patients' IgE response to major/minor Aspergillus allergens. This approach will be helpful to identify disease eliciting molecules in the individual patients (component resolved diagnosis) and may improve allergen-specific immunotherapy.

Allergen-Specific Cytokine Polarization Protects Shetland Ponies against Culicoides obsoletus-Induced Insect Bite Hypersensitivity

PubMed Central

Meulenbroeks, Chantal; van der Lugt, Jaco J.; van der Meide, Nathalie M. A.; Willemse, Ton; Rutten, Victor P. M. G.; Zaiss, Dietmar M. W.

2015-01-01

The immunological mechanisms explaining development of an allergy in some individuals and not in others remain incompletely understood. Insect bite hypersensitivity (IBH) is a common, seasonal, IgE-mediated, pruritic skin disorder that affects considerable proportions of horses of different breeds, which is caused by bites of the insect Culicoides obsoletus (C. obsoletus). We investigated the allergen-specific immune status of individual horses that had either been diagnosed to be healthy or to suffer of IBH. Following intradermal allergen injection, skin biopsies were taken of IBH-affected and healthy ponies and cytokine expression was determined by RT-PCR. In addition, allergen-specific antibody titers were measured and cytokine expression of in vitro stimulated, allergen-specific CD4 T-cells was determined. 24 hrs after allergen injection, a significant increase in mRNA expression of the type-2 cytokine IL-4 was observed in the skin of IBH-affected Shetland ponies. In the skin of healthy ponies, however, an increase in IFNγ mRNA expression was found. Analysis of allergen-specific antibody titers revealed that all animals produced allergen-specific antibodies, and allergen-specific stimulation of CD4 T-cells revealed a significant higher percentage of IFNγ-expressing CD4 T-cells in healthy ponies compared to IBH-affected ponies. These data indicate that horses not affected by IBH, in contrast to the so far established dogma, are not immunologically ignorant but have a Th1-skewed allergen-specific immune response that appears to protect against IBH-associated symptoms. To our knowledge this is the first demonstration of a natural situation, in which an allergen-specific immune skewing is protective in an allergic disorder. PMID:25901733

Deteriorated housing contributes to high cockroach allergen levels in inner-city households.

PubMed Central

Rauh, Virginia A; Chew, Ginger R; Garfinkel, Robin S

2002-01-01

The high prevalence of childhood asthma in low-income, inner-city populations is not fully understood but has been at least partly attributed to the disproportionate exposures associated with socioeconomic disadvantage. The contribution of indoor allergens to asthma is well documented, but links between socioeconomic disadvantage and indoor allergen levels are not clear. We investigated levels of cockroach allergens (Bla g 2) in a sample of 132 Dominican or African American low-income households with young children in northern Manhattan in New York City (40% were receiving public assistance) to determine whether the distribution of allergens is a function of housing deterioration. Deterioration was measured by the presence and number of physical housing problems (holes in the ceilings and walls, water damage, etc.). More than 50% of the sample had two or more types of housing dilapidation, and 67% of the sample reported cockroach sightings in their homes. Samples of dust were collected from kitchen and bedroom surfaces. We hypothesized that the greater the dilapidation, the higher the allergen levels, independent of income, sociocultural factors, and pest-control methods. In addition, we hypothesized that the homes of families characterized by frequent moves (23.5%) would have higher allergen levels than more stable families. Results showed significant positive associations between housing deterioration and allergen levels in kitchens, after adjusting for income and ethnicity, with independent effects of residential stability (p< 0.05). Bedroom allergen levels were associated with housing instability (p < 0.01) and ethnicity (p< 0.01). Findings demonstrated that indoor household allergen levels are related to degree of household disrepair, after adjusting for individual family attributes, suggesting that social-structural aspects of housing may be appropriate targets for public health interventions designed to reduce allergen exposure. PMID:11929744

Natural history of allergic sensitization in infants with early-onset atopic dermatitis: results from ORCA Study.

PubMed

Just, Jocelyne; Deslandes-Boutmy, Emmanuelle; Amat, Flore; Desseaux, Kristell; Nemni, Ariane; Bourrat, Emmanuelle; Sahraoui, Fatia; Pansé, Isabelle; Bagot, Martine; Fouéré, Sébastien

2014-11-01

Early-onset atopic dermatitis (AD) is a particular phenotype that may convey a risk of developing multiple sensitizations to allergens but little is known about the pathway of sensitization. The aims of this study were to describe the natural history of sensitization to allergens for this phenotype and to identify the most predictive marker associated with the risk of developing sensitization to inhaled allergens in a well-selected cohort of infants with AD. Infants with active AD were enrolled and prospectively explored for biological markers of atopy every year until the age of 6 yr. Allergic sensitization was defined as the presence of positive specific IgEs to allergens and multiple sensitizations as being sensitized to ≥2 allergens. Elevated blood eosinophilia was defined as an eosinophil blood count ≥470 eosinophils/mm(3) and elevated total IgE as a serum IgE level ≥45 kU/l. Two hundred and twenty-nine infants were included. Elevated blood eosinophilia was observed at baseline in 60 children (26.2%) and elevated total IgE in 85 (37.1%). When elevated at baseline, eosinophilia and IgE levels remained significantly higher during the follow-up period. Sensitization to food allergens decreased from 58% to 34%, whereas sensitization to inhaled allergens increased over time from 17% to 67%. Initial multiple sensitizations to food allergens were the most predictive factor for the risk of developing sensitization to inhaled allergens at 6 yr (OR 3.72 [1.68-8.30] p < 0.001). In the early-onset AD phenotype, multiple sensitization to food allergens conveys a higher risk of sensitization to inhaled allergens than single sensitization. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

High serum levels of allergen specific IgG-4 (asIgG-4) for common food allergens in healthy blood donors.

PubMed

Kruszewski, J; Raczka, A; Kłos, M; Wiktor-Jedrzejczak, W

1994-01-01

High serum levels of asIgG-4 against common food allergens are found in many patients with symptoms suggesting food allergy. The same patients are frequently negative for allergen specific IgE (asIgE) against the same allergens. These data were frequently interpreted as suggestive of a role of asIgG-4 in food allergy. In order to evaluate this hypothesis we tested serum levels of asIgG-4 against food allergens in young blood donors without any signs or history of food allergy. Fifty young healthy male donors were evaluated. The serum levels of IgE, and asIgE and IgG-4 against 14 common food allergens were determined. The studies were carried out using commercially available 3M Diagnostics Systems kits. AsIgG-4 against food allergens were found in sera of 92% blood donors, and in 62% of these healthy persons the levels of asIgG-4 were higher than 10.0 micrograms/ml. In a small proportion of patients, high serum levels of IgE and asIgE against the same food and/or inhalant allergens were found. Common occurrence of asIgG-4 against food allergens in healthy persons (without any symptoms which could suggest allergy or food intolerance) argues against the possible participation of these antibodies in the pathogenesis of food allergy. It is possible that their occurrence is the result of immunization against food antigens (allergens). It remains to be resolved whether the presence of these antibodies represents an epiphenomenon or may have some other biological role.

Determination of irritant threshold concentrations of multiple tree, grass, weed and mould allergens for intradermal testing of horses residing in the southern USA.

PubMed

Lane, Martha J; Pucheu-Haston, Cherie M; Kearney, Michael T; Woodward, Michelle

2017-12-01

Appropriate allergen threshold concentrations (TCs) for intradermal testing (IDT) have not been established in horses for many pollen and mould allergens. To determine the TCs in non-allergic horses and describe the frequency of late phase reactions for 26 allergens, including trees, grasses, weeds and moulds in horses residing in the southern Unites States. Twenty four clinically normal horses in the southern United States. Threshold concentrations for different allergens were determined using IDT subjective measurements at 30 minutes. Delayed reactions were evaluated at 4 and 24 h. Threshold concentrations (all PNU/mL) were established for eight tree allergens (black willow 1,000, box elder 1,000, live oak 1,000, pecan 2,000, white ash 4,000, red oak 4,000, red mulberry 2,000 and green ash 2,000); two grass allergens (Johnson grass 250 PNU/mL and Kentucky blue grass 500 PNU/mL); two weeds (carelessweed 1,000 PNU/mL, great ragweed 500 PNU/mL) and one mould (Curvularia 8,000 PNU/mL). The TC was not determined due to excessive reactivity at the lowest concentration tested (1,000 PNU/mL) for bahia and perennial rye grass. Eleven other allergens did not meet the criteria to establish a TC when evaluated at 30 min due to lack of positive reactions. Multiple allergens caused positive reactions in ≥10% of horses at 4 h. Reactions at 24 h were rare with the exception of one horse. This study identified intradermal TC for multiple pollen and mould allergens in horses. These values may prove useful for optimizing allergen concentrations for IDT of allergic horses. © 2017 ESVD and ACVD.

Quantitative measurement of IgE antibodies to purified allergens using streptavidin linked to a high-capacity solid phase.

PubMed

Erwin, Elizabeth A; Custis, Natalie J; Satinover, Shama M; Perzanowski, Matthew S; Woodfolk, Judith A; Crane, Julian; Wickens, Kristin; Platts-Mills, Thomas A E

2005-05-01

Commercially available assays for IgE antibody provide results in international units per milliliter for many allergen extracts, but this is not easily achieved with purified or novel allergens. To develop assays for IgE antibody suitable for purified or novel allergens by using a commercially available immunosorbent. Streptavidin coupled to a high-capacity immunosorbent (CAP) was used to bind biotinylated purified allergens from mite (Der p 1 and Der p 2), cat (Fel d 1), and dog (Can f 1). Assays for IgE antibody to these allergens were performed on sera from children (asthma and control) as well as adults with atopic dermatitis. The results were validated by serial dilution of sera with high and low levels of IgE antibody and were quantitated in international units per milliliter by using a standard curve. Values for IgE antibody to Der p 1, Der p 2, and Fel d 1 correlated with values obtained with the allergen extracts (r2 = 0.80, 0.84, and 0.95, respectively; P < .001 in each case). Furthermore, the values for IgE antibody in sera from children with high exposure to mite and cat allergens demonstrated 10-fold higher levels of IgE antibody to Der p 1 and Der p 2 than to Fel d 1 (P < .001). The streptavidin immunosorbent technique provides a new method for quantifying IgE antibody to purified proteins. The results provide evidence about the high quantities of IgE antibody to purified inhalant allergens in patients with atopic dermatitis. In addition, the results demonstrate major differences in IgE antibodies specific for mite and cat allergens among children with high exposure to both allergens.

Natural clinical tolerance to peanut in African patients is caused by poor allergenic activity of peanut IgE.

PubMed

Wollmann, E; Hamsten, C; Sibanda, E; Ochome, M; Focke-Tejkl, M; Asarnoj, A; Önell, A; Lilja, G; Gallerano, D; Lupinek, C; Thalhamer, T; Weiss, R; Thalhamer, J; Wickman, M; Valenta, R; van Hage, M

2015-06-01

In Africa, peanuts are frequently consumed, but severe allergic reactions are rare. We investigated immunological patterns of clinical tolerance to peanut in peanut-sensitized but asymptomatic patients from central Africa compared to peanut-allergic and peanut-sensitized but asymptomatic patients from Sweden. Sera from allergic patients (n = 54) from Zimbabwe sensitized to peanut but without allergic symptoms to peanut, and sera from peanut-allergic (n = 25) and peanut-sensitized but asymptomatic (n = 25) patients from Sweden were analyzed toward peanut allergen components (Ara h 1-3, 6, 8-9) and other allergen molecules from important allergen sources using microarray. IgE to Ara h 2 peptide epitopes was analyzed, and allergenic activity was assessed by basophil activation assay. Forty-six percent of the African and all peanut-allergic Swedish patients showed IgE toward one of the highly allergenic peanut allergens (Ara h 1-3, 6, 9). However, 48% of the African patients had IgE to cross-reactive carbohydrate determinants (CCDs) with low allergenic activity and 60% of the Swedish asymptomatic patients had IgE against the PR protein Ara h 8. IgG and IgG4 specificities and levels could not discriminate between the African asymptomatic and Swedish peanut-allergic patients. Asymptomatic patients almost lacked IgE to Ara h 2 peptides, which were recognized by peanut-allergic patients. Peanut IgE from peanut asymptomatic patients showed poor allergenic activity compared with IgE from peanut-allergic patients. Natural clinical tolerance to peanut in the African patients can be caused by IgE to low allergenic peanut components and by poor allergenic activity of peanut-specific IgE. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Comparative and Evolutionary Analysis of Grass Pollen Allergens Using Brachypodium distachyon as a Model System.

PubMed

Sharma, Akanksha; Sharma, Niharika; Bhalla, Prem; Singh, Mohan

2017-01-01

Comparative genomics have facilitated the mining of biological information from a genome sequence, through the detection of similarities and differences with genomes of closely or more distantly related species. By using such comparative approaches, knowledge can be transferred from the model to non-model organisms and insights can be gained in the structural and evolutionary patterns of specific genes. In the absence of sequenced genomes for allergenic grasses, this study was aimed at understanding the structure, organisation and expression profiles of grass pollen allergens using the genomic data from Brachypodium distachyon as it is phylogenetically related to the allergenic grasses. Combining genomic data with the anther RNA-Seq dataset revealed 24 pollen allergen genes belonging to eight allergen groups mapping on the five chromosomes in B. distachyon. High levels of anther-specific expression profiles were observed for the 24 identified putative allergen-encoding genes in Brachypodium. The genomic evidence suggests that gene encoding the group 5 allergen, the most potent trigger of hay fever and allergic asthma originated as a pollen specific orphan gene in a common grass ancestor of Brachypodium and Triticiae clades. Gene structure analysis showed that the putative allergen-encoding genes in Brachypodium either lack or contain reduced number of introns. Promoter analysis of the identified Brachypodium genes revealed the presence of specific cis-regulatory sequences likely responsible for high anther/pollen-specific expression. With the identification of putative allergen-encoding genes in Brachypodium, this study has also described some important plant gene families (e.g. expansin superfamily, EF-Hand family, profilins etc) for the first time in the model plant Brachypodium. Altogether, the present study provides new insights into structural characterization and evolution of pollen allergens and will further serve as a base for their functional characterization in related grass species.

Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen

PubMed Central

Resch, Yvonne; Blatt, Katharina; Malkus, Ursula; Fercher, Christian; Swoboda, Ines; Focke-Tejkl, Margit; Chen, Kuan-Wei; Seiberler, Susanne; Mittermann, Irene; Lupinek, Christian; Rodriguez-Dominguez, Azahara; Zieglmayer, Petra; Zieglmayer, René; Keller, Walter; Krzyzanek, Vladislav; Valent, Peter; Valenta, Rudolf; Vrtala, Susanne

2016-01-01

Background The house dust mite (HDM) allergen Der p 18 belongs to the glycoside hydrolase family 18 chitinases. The relevance of Der p 18 for house dust mite allergic patients has only been partly investigated. Objective To perform a detailed characterization of Der p 18 on a molecular, structural and immunological level. Methods Der p 18 was expressed in E. coli, purified to homogeneity, tested for chitin-binding activity and its secondary structure was analyzed by circular dichroism. Der p 18-specific IgG antibodies were produced in rabbits to localize the allergen in mites using immunogold electron microscopy and to search for cross-reactive allergens in other allergen sources (i.e. mites, crustacea, mollusca and insects). IgE reactivity of rDer p 18 was tested with sera from clinically well characterized HDM-allergic patients (n = 98) and its allergenic activity was analyzed in basophil activation experiments. Results Recombinant Der p 18 was expressed and purified as a folded, biologically active protein. It shows weak chitin-binding activity and partial cross-reactivity with Der f 18 from D. farinae but not with proteins from the other tested allergen sources. The allergen was mainly localized in the peritrophic matrix of the HDM gut and to a lower extent in fecal pellets. Der p 18 reacted with IgE from 10% of mite allergic patients from Austria and showed allergenic activity when tested for basophil activation in Der p 18-sensitized patients. Conclusion Der p 18 is a rather genus-specific minor allergen with weak chitin-binding activity but exhibits allergenic activity and therefore should be included in diagnostic test panels for HDM allergy. PMID:27548813

Isolation of a high-affinity Bet v 1-specific IgG-derived ScFv from a subject vaccinated with hypoallergenic Bet v 1 fragments.

PubMed

Gadermaier, E; Marth, K; Lupinek, C; Campana, R; Hofer, G; Blatt, K; Smiljkovic, D; Roder, U; Focke-Tejkl, M; Vrtala, S; Keller, W; Valent, P; Valenta, R; Flicker, S

2018-01-09

Recombinant hypoallergenic allergen derivatives have been used in clinical immunotherapy studies, and clinical efficacy seems to be related to the induction of blocking IgG antibodies recognizing the wild-type allergens. However, so far no treatment-induced IgG antibodies have been characterized. To clone, express, and characterize IgG antibodies induced by vaccination with two hypoallergenic recombinant fragments of the major birch pollen allergen, Bet v 1 in a nonallergic subject. A phage-displayed combinatorial single-chain fragment (ScFv) library was constructed from blood of the immunized subject and screened for Bet v 1-reactive antibody fragments. ScFvs were tested for specificity and cross-reactivity to native Bet v 1 and related pollen and food allergens, and epitope mapping was performed. Germline ancestor genes of the antibody were analyzed with the ImMunoGeneTics (IMGT) database. The affinity to Bet v 1 and cross-reactive allergens was determined by surface plasmon resonance measurements. The ability to inhibit patients' IgE binding to ELISA plate-bound allergens and allergen-induced basophil activation was assessed. A combinatorial ScFv library was obtained from the vaccinated donor after three injections with the Bet v 1 fragments. Despite being almost in germline configuration, ScFv (clone H3-1) reacted with high affinity to native Bet v 1 and homologous allergens, inhibited allergic patients' polyclonal IgE binding to Bet v 1, and partially suppressed allergen-induced basophil activation. Immunization with unfolded hypoallergenic allergen derivatives induces high-affinity antibodies even in nonallergic subjects which recognize the folded wild-type allergens and inhibit polyclonal IgE binding of allergic patients. © 2018 The Authors. Allergy Published by John Wiley & Sons Ltd.

Mechanism for initiation of food allergy: Dependence on skin barrier mutations and environmental allergen costimulation.

PubMed

Walker, Matthew T; Green, Jeremy E; Ferrie, Ryan P; Queener, Ashley M; Kaplan, Mark H; Cook-Mills, Joan M

2018-05-01

Mechanisms for the development of food allergy in neonates are unknown but clearly linked in patient populations to a genetic predisposition to skin barrier defects. Whether skin barrier defects contribute functionally to development of food allergy is unknown. The purpose of the study was to determine whether skin barrier mutations, which are primarily heterozygous in patient populations, contribute to the development of food allergy. Mice heterozygous for the filaggrin (Flg) ft and Tmem79 ma mutations were skin sensitized with environmental and food allergens. After sensitization, mice received oral challenge with food allergen, and then inflammation, inflammatory mediators, and anaphylaxis were measured. We define development of inflammation, inflammatory mediators, and food allergen-induced anaphylaxis in neonatal mice with skin barrier mutations after brief concurrent cutaneous exposure to food and environmental allergens. Moreover, neonates of allergic mothers have increased responses to suboptimal sensitization with food allergens. Importantly, responses to food allergens by these neonatal mice were dependent on genetic defects in skin barrier function and on exposure to environmental allergens. ST2 blockade during skin sensitization inhibited the development of anaphylaxis, antigen-specific IgE, and inflammatory mediators. Neonatal anaphylactic responses and antigen-specific IgE were also inhibited by oral pre-exposure to food allergen, but interestingly, this was blunted by concurrent pre-exposure of the skin to environmental allergen. These studies uncover mechanisms for food allergy sensitization and anaphylaxis in neonatal mice that are consistent with features of human early-life exposures and genetics in patients with clinical food allergy and demonstrate that changes in barrier function drive development of anaphylaxis to food allergen. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Search for Allergens from the Pollen Proteome of Sunflower (Helianthus annuus L.): A Major Sensitizer for Respiratory Allergy Patients.

PubMed

Ghosh, Nandini; Sircar, Gaurab; Saha, Bodhisattwa; Pandey, Naren; Gupta Bhattacharya, Swati

2015-01-01

Respiratory allergy triggered by pollen allergens is increasing at an alarming rate worldwide. Sunflower pollen is thought to be an important source of inhalant allergens. Present study aims to identify the prevalence of sunflower pollinosis among the Indian allergic population and characterizes the pollen allergens using immuno-proteomic tools. Clinico-immunological tests were performed to understand the prevalence of sensitivity towards sunflower pollen among the atopic population. Sera from selected sunflower positive patients were used as probe to detect the IgE-reactive proteins from the one and two dimensional electrophoretic separated proteome of sunflower pollen. The antigenic nature of the sugar moiety of the glycoallergens was studied by meta-periodate modification of IgE-immunoblot. Finally, these allergens were identified by mass-spectrometry. Prevalence of sunflower pollen sensitization was observed among 21% of the pollen allergic population and associated with elevated level of specific IgE and histamine in the sera of these patients. Immunoscreening of sunflower pollen proteome with patient sera detected seven IgE-reactive proteins with varying molecular weight and pI. Hierarchical clustering of 2D-immunoblot data highlighted three allergens characterized by a more frequent immuno-reactivity and increased levels of IgE antibodies in the sera of susceptible patients. These allergens were considered as the major allergens of sunflower pollen and were found to have their glycan moiety critical for inducing IgE response. Homology driven search of MS/MS data of these IgE-reactive proteins identified seven previously unreported allergens from sunflower pollen. Three major allergenic proteins were identified as two pectate lyases and a cysteine protease. Novelty of the present report is the identification of a panel of seven sunflower pollen allergens for the first time at immuno-biochemical and proteomic level, which substantiated the clinical evidence of sunflower allergy. Further purification and recombinant expression of these allergens will improve component-resolved diagnosis and therapy of pollen allergy.

FoxP2 protein levels regulate cell morphology changes and migration patterns in the vertebrate developing telencephalon.

PubMed

Garcia-Calero, Elena; Botella-Lopez, Arancha; Bahamonde, Olga; Perez-Balaguer, Ariadna; Martinez, Salvador

2016-07-01

In the mammalian telencephalon, part of the progenitor cells transition from multipolar to bipolar morphology as they invade the mantle zone. This associates with changing patterns of radial migration. However, the molecules implicated in these morphology transitions are not well known. In the present work, we analyzed the function of FoxP2 protein in this process during telencephalic development in vertebrates. We analyzed the expression of FoxP2 protein and its relation with cell morphology and migratory patterns in mouse and chicken developing striatum. We observed FoxP2 protein expressed in a gradient from the subventricular zone to the mantle layer in mice embryos. In the FoxP2 low domain cells showed multipolar migration. In the striatal mantle layer where FoxP2 protein expression is higher, cells showed locomoting migration and bipolar morphology. In contrast, FoxP2 showed a high and homogenous expression pattern in chicken striatum, thus bipolar morphology predominated. Elevation of FoxP2 in the striatal subventricular zone by in utero electroporation promoted bipolar morphology and impaired multipolar radial migration. In mouse cerebral cortex we obtained similar results. FoxP2 promotes transition from multipolar to bipolar morphology by means of gradiental expression in mouse striatum and cortex. Together these results indicate a role of FoxP2 differential expression in cell morphology control of the vertebrate telencephalon.

Mutant IDH1 Disrupts the Mouse Subventricular Zone and Alters Brain Tumor Progression

PubMed Central

Pirozzi, Christopher J.; Carpenter, Austin B.; Waitkus, Matthew S.; Wang, Catherine Y.; Zhu, Huishan; Hansen, Landon J.; Chen, Lee H.; Greer, Paula K.; Feng, Jie; Wang, Yu; Bock, Cheryl B.; Fan, Ping; Spasojevic, Ivan; McLendon, Roger E.; Bigner, Darell D.; He, Yiping; Yan, Hai

2017-01-01

IDH1 mutations occur in the majority of low-grade gliomas and lead to the production of the oncometabolite, D-2-hydroxyglutarate (D-2HG). To understand the effects of tumor-associated mutant IDH1 (IDH1-R132H) on both the neural stem cell (NSC) population and brain tumorigenesis, genetically faithful cell lines and mouse model systems were generated. Here, it is reported that mouse NSCs expressing Idh1-R132H displayed reduced proliferation due to p53-mediated cell cycle arrest as well as a decreased ability to undergo neuronal differentiation. In vivo, Idh1-R132H expression reduced proliferation of cells within the germinal zone of the subventricular zone (SVZ). The NSCs within this area were dispersed and disorganized in mutant animals, suggesting that Idh1-R132H perturbed the NSCs and the microenvironment from which gliomas arise. Additionally, tumor-bearing animals expressing mutant Idh1 displayed a prolonged survival and also overexpressed Olig2, features consistent with IDH1-mutated human gliomas. These data indicate that mutant Idh1 disrupts the NSC microenvironment and the candidate cell of origin for glioma; thus, altering the progression of tumorigenesis. Additionally, this study provides a mutant Idh1 brain tumor model that genetically recapitulates human disease, laying the foundation for future investigations on mutant IDH1-mediated brain tumorigenesis and targeted therapy. PMID:28148827

Sequential allergen desensitization of basophils is non-specific and may involve p38 MAPK.

PubMed

Witting Christensen, S K; Kortekaas Krohn, I; Thuraiaiyah, J; Skjold, T; Schmid, J M; Hoffmann, H J H

2014-10-01

Sequential allergen desensitization provides temporary tolerance for allergic patients. We adapted a clinical protocol to desensitize human blood basophils ex vivo and investigated the mechanism and allergen specificity. We included 28 adult, grass allergic subjects. The optimal, activating allergen concentration was determined by measuring activated CD63(+) CD193(+) SS(Low) basophils in a basophil activation test with 8 log-dilutions of grass allergen. Basophils in whole blood were desensitized by incubation with twofold to 2.5-fold increasing allergen doses in 10 steps starting at 1 : 1000 of the optimal dose. Involvement of p38 mitogen-activated protein kinase (MAPK) was assessed after 3 min of allergen stimulation (n = 7). Allergen specificity was investigated by desensitizing cells from multi-allergic subjects with grass allergen and challenging with optimal doses of grass, birch, recombinant house dust mite (rDer p2) allergen or anti-IgE (n = 10). Desensitization reduced the fraction of blood basophils responding to challenge with an optimal allergen dose from a median (IQR) 81.0% (66.3-88.8) to 35.4% (19.8-47.1, P < 0.0001). CD63 MFI expression was reduced from 68 248 (29 336-92 001) to 30 496 (14 046-46 179, P < 0.0001). Basophils from multi-allergic subjects were desensitized with grass allergen. Challenge with grass allergen resulted in 39.6% activation (15.8-58.3). An unrelated challenge (birch, rDer p2 or anti-IgE) resulted in 53.4% activation (30.8-66.8, P = 0.16 compared with grass). Desensitization reduced p38 MAPK phosphorylation from a median 48.1% (15.6-92.8) to 26.1% (7.4-71.2, P = 0.047) and correlated with decrease in CD63 upregulation (n = 7, r > 0.79, P < 0.05). Desensitization attenuated basophil response rapidly and non-specifically at a stage before p38 MAPK phosphorylation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

In silico analyses of structural and allergenicity features of sapodilla (Manilkara zapota) acidic thaumatin-like protein in comparison with allergenic plant TLPs.

PubMed

Ashok Kumar, Hassan G; Venkatesh, Yeldur P

2014-02-01

Thaumatin-like proteins (TLPs) belong to the pathogenesis-related family (PR-5) of plant defense proteins. TLPs from only 32 plant genera have been identified as pollen or food allergens. IgE epitopes on allergens play a central role in food allergy by initiating cross-linking of specific IgE on basophils/mast cells. A comparative analysis of pollen- and food-allergenic TLPs is lacking. The main objective of this investigation was to study the structural and allergenicity features of sapodilla (Manilkara zapota) acidic TLP (TLP 1) by in silico methods. The allergenicity prediction of composite sequence of sapodilla TLP 1 (NCBI B3EWX8.1, G5DC91.1) was performed using FARRP, Allermatch and Evaller web tools. A homology model of the protein was generated using banana TLP template (1Z3Q) by HHPRED-MODELLER. B-cell linear epitope prediction was performed using BCpreds and BepiPred. Sapodilla TLP 1 matched significantly with allergenic TLPs from olive, kiwi, bell pepper and banana. IgE epitope prediction as performed using AlgPred indicated the presence of 2 epitopes (epitope 1: residues 36-48; epitope 2: residues 51-63), and a comprehensive analysis of all allergenic TLPs displayed up to 3 additional epitopes on other TLPs. It can be inferred from these analyses that plant allergenic TLPs generally carry 2-3 IgE epitopes. ClustalX alignments of allergenic TLPs indicate that IgE epitopes 1 and 2 are common in food allergenic TLPs, and IgE epitopes 2 and 3 are common in pollen allergenic TLPs; IgE epitope 2 overlaps with a portion of the thaumatin family signature. The secondary structural elements of TLPs vary markedly in regions 1 and 2 which harbor all the predicted IgE epitopes in all food and pollen TLPs in either of the region. Further, based on the number of IgE epitopes, food TLPs are grouped into rosid and non-rosid clades. The number and distribution of the predicted IgE epitopes among the allergenic TLPs may explain the specificity of food or pollen allergy as well as the varied degree of cross-reactivity among plant foods and/or pollens. Copyright © 2013 Elsevier Ltd. All rights reserved.

Charting novel allergens from date palm pollen (Phoenix sylvestris) using homology driven proteomics.

PubMed

Saha, Bodhisattwa; Bhattacharya, Swati Gupta

2017-08-08

Pollen grains from Phoenix sylvestris (date palm), a commonly cultivated tree in India has been found to cause severe allergic diseases in an increasing percentage of hypersensitive individuals. To unearth its allergenic components, pollen protein were profiled by two-dimensional gel electrophoresis followed by immunoblotting with date palm pollen sensitive patient sera. Allergens were identified by MALDI-TOF/TOF employing a layered proteomic approach combining conventional database dependent search and manual de novo sequencing followed by homology-based search as Phoenix sylvestris is unsequenced. Derivatization of tryptic peptides by acetylation has been demonstrated to differentiate the 'b' from the 'y' ions facilitating efficient de novo sequencing. Ten allergenic proteins were identified, out of which six showed homology with known allergens while others were reported for the first time. Amongst these, isoflavone reductase, beta-conglycinin, S-adenosyl methionine synthase, 1, 4 glucan synthase and beta-galactosidase were commonly reported as allergens from coconut pollen and presumably responsible for cross-reactivity. One of the allergens had IgE binding epitope recognized by its glycan moiety. The allergenic potency of date palm pollen has been demonstrated using in vitro tests. The identified allergens can be used to develop vaccines for immunotherapy against date palm pollen allergy. Identification of allergenic proteins from sources harboring them is essential in developing therapeutic interventions. This is the first comprehensive study on the identification of allergens from Phoenix sylvestris (date palm) pollen, one of the major aeroallergens in India using a proteomic approach. Proteomic methods are being increasingly used to identify allergens. However, since many of these proteins arise from species which are un-sequenced, it becomes difficult to interpret those using conventional proteomics. Date palm being an unsequenced species, the IgE-reactive proteins have been identified using a stratified proteomic workflow incorporating manual de novo sequencing and homology-based proteomics. This study also gives an insight into the presence of glycan nature of the IgE binding epitopes. Five proteins have been found to be common with coconut pollen allergens and presumably responsible for cross-reactivity. These can be used in diagnostics to differentiate patient cohorts allergic to both coconut and date palm pollen from true date palm pollen allergic subjects. This would also determine better specific immunotherapy regimes between the two cohorts. The allergens identified herein have potential towards vaccine development in date palm pollen allergy as well as in enriching the existing catalogue of allergenic proteins. Copyright © 2017. Published by Elsevier B.V.

Dust mite, cockroach, cat, and dog allergen concentrations in homes of asthmatic children in the northeastern United States: impact of socioeconomic factors and population density.

PubMed Central

Leaderer, Brian P; Belanger, Kathleen; Triche, Elizabeth; Holford, Theodore; Gold, Diane R; Kim, Young; Jankun, Thomas; Ren, Ping; McSharry Je, Jean-ellen; Platts-Mills, Thomas A E; Chapman, Martin D; Bracken, Michael B

2002-01-01

Home exposures to aeroallergens are an important environmental factor in allergic sensitization and in the development and exacerbation of asthma. We assessed variations in home concentrations of dust mite, cockroach, cat, and dog allergens in dust collected in the main living areas of asthmatics' homes by family income, mother's education, dwelling type, population density, household population density, and ethnicity in Connecticut and south-central Massachusetts. Dust samples were collected at the time of home interview in 999 homes as part of an ongoing longitudinal birth cohort study of 1,002 infants and their asthmatic siblings. The analysis employed lower and upper cut points for group 1 dust mite (> or = 2.0 microg/g and > or = 10 microg/g), cockroach (> or = 1.0 U/g and > or = 4.0 U/g), cat (> or = 1.0 microg/g and > or = 8.0 ug/g), and dog (> or = 2.0 microg/g and > or = 10.0 microg/g) allergens. Subject residences were geocoded to assess population density from the U.S. Census, and multiple logistic regression was used to control for confounding. The portion of homes at the lower cut point for dust mite, cockroach, cat, and dog allergens were 46.9%, 24.9%, 42.2%, and 35.6%, respectively; the upper cut point for each of the allergens was reached in 22.4%, 13.4%, 21.0%, and 22.9% of the homes, respectively. In all, 86.0% of the homes had at least one allergen at the lower cut point, and 58.0% had at least one allergen at the upper cut point. Forty-nine percent of the homes had two or more allergens at the lower cut point, and 19.7% had two or more allergens at the upper cut point. Higher education of the mother, higher household income, living in a single-family home in a less densely populated area with fewer people per room, and being a white household were associated with elevated dust mite, cat, and dog allergens and low cockroach allergen. In contrast, low income, living in a multifamily home in a high population density area with a higher occupancy rate per room, and being a Hispanic or black household were associated with elevated cockroach allergens and low concentrations of dust mite, cat, and dog allergens. Although the presence of an individual allergen is more likely associated with one or more socioeconomic or ethnic factors, most homes typically have multiple allergen burdens in excess of concentrations thought to be associated with sensitization and exacerbation of asthma. Mite and cockroach allergens have distinct and opposite associations with socioeconomic factors and population density. PMID:11940461

Structure, Function and Epitope Mapping the Peanut Panallergen Ara h 8

USDA-ARS?s Scientific Manuscript database

The incidence of peanut allergy continues to rise in the US and Europe. Whereas exposure to the major allergens Ara h 1, 2, 3, and 6 can cause fatal anaphylaxis, exposure to the minor allergens usually does not. Ara h 8 is a minor allergen. Importantly, it is the minor food allergens that are though...

Structure and function of the peanut panallergen Ara h 8

USDA-ARS?s Scientific Manuscript database

The incidence of peanut allergy continues to rise in the US and Europe; whereas, exposure to the major allergens Ara h 1, 2, 3, and 6 can cause fatal anaphylaxis, exposure to the minor allergens usually does not. Ara h 8 is a minor allergen. Importantly, it is the minor food allergens that are tho...

Treatment with oleic acid reduces IgE binding to peanut and cashew allergens

USDA-ARS?s Scientific Manuscript database

Oleic acid (OA) is known to bind and change the bioactivities of proteins, such as a-lactalbumin and ß-lactoglobulin in vitro. The objective of this study was to determine if OA binds to allergens from a peanut extract or cashew allergen and changes their allergenic properties. Peanut extract or c...

Allergens in School Settings: Results of Environmental Assessments in 3 City School Systems

ERIC Educational Resources Information Center

Abramson, Stuart L.; Turner-Henson, Anne; Anderson, Lise; Hemstreet, Mary P.; Bartholomew, L. Kay; Joseph, Christine L. M.; Tang, Shenghui; Tyrrell, Shellie; Clark, Noreen M.; Ownby, Dennis

2006-01-01

Environmental allergens are major triggers for pediatric asthma. While children's greatest exposure to indoor allergens is in the home, other public places where children spend a large amount of time, such as school and day care centers, may also be sources of significant allergen encounters. The purpose of this article is to describe schoolroom…

Application of gamma irradiation for inhibition of food allergy

NASA Astrophysics Data System (ADS)

Byun, Myung-Woo; Lee, Ju-Woon; Yook, Hong-Sun; Jo, Cheorun; Kim, Hee-Yun

2002-03-01

This study was carried out to evaluate the application of food irradiation technology as a method for reducing food allergy. Milk β-lactoglobulin, chicken egg albumin, and shrimp tropomyosin were used as model food allergens for experiments on allergenic and molecular properties by gamma irradiation. The amount of intact allergens in an irradiated solution was reduced by gamma irradiation depending upon the dose. These results showed that epitopes on the allergens were structurally altered by radiation treatment and that the irradiation technology can be applied to reduce allergenicity of allergic foods.

Towards a cure for food allergy.

PubMed

Skripak, Justin M; Sampson, Hugh A

2008-12-01

Over the past two decades, food allergies have become both more prevalent and long lasting. This burgeoning problem has not been met with any therapeutic options to date, and patients must attempt to avoid known allergenic foods and treat any allergic reactions with 'as-needed' medications. There are a number of promising emerging therapeutic modalities for food allergy, including allergen-specific and allergen non-specific immunotherapeutic approaches. Although the allergen-specific approaches have some distinct differences, they all attempt to induce tolerance by exposing the patient to an allergen via the mucosal route (oral tolerance induction). Allergen non-specific approaches include biologics to suppress free total IgE levels (e.g. anti-IgE antibody) or to induce more general immune suppression (Chinese herbal medication).

Establishment of an in silico phototoxicity prediction method by combining descriptors related to photo-absorption and photo-reaction.

PubMed

Haranosono, Yu; Kurata, Masaaki; Sakaki, Hideyuki

2014-08-01

One of the mechanisms of phototoxicity is photo-reaction, such as reactive oxygen species (ROS) generation following photo-absorption. We focused on ROS generation and photo-absorption as key-steps, because these key-steps are able to be described by photochemical properties, and these properties are dependent on chemical structure. Photo-reactivity of a compound is described by HOMO-LUMO Gap (HLG), generally. Herein, we showed that HLG can be used as a descriptor of the generation of reactive oxygen species. Moreover, the maximum-conjugated π electron number (PENMC), which we found as a descriptor of photo-absorption, could also predict in vitro phototoxicity. Each descriptor could predict in vitro phototoxicity with 70.0% concordance, but there was un-predicted area found (gray zone). Interestingly, some compounds in each gray zone were not common, indicating that the combination of two descriptors could improve prediction potential. We reset the cut-off lines to define positive zone, negative zone and gray zone for each descriptor. Thereby we overlapped HLG and PENMC in a graph, and divided the total area to nine zones with cut-off lines of each descriptor. The rules to prediction were decided to achieve the best concordance, and the concordances were improved up to 82.8% for self-validation, 81.6% for cross-validation. We found common properties among false positive or negative compounds, photo-reactive structure and photo-allergenic, respectively. In addition, our method could be adapted to compounds rich in structural diversity using only chemical structure without any statistical analysis and complicated calculation.

In vivo MR guided boiling histotripsy in a mouse tumor model evaluated by MRI and histopathology.

PubMed

Hoogenboom, Martijn; Eikelenboom, Dylan; den Brok, Martijn H; Veltien, Andor; Wassink, Melissa; Wesseling, Pieter; Dumont, Erik; Fütterer, Jurgen J; Adema, Gosse J; Heerschap, Arend

2016-06-01

Boiling histotripsy (BH) is a new high intensity focused ultrasound (HIFU) ablation technique to mechanically fragmentize soft tissue into submicrometer fragments. So far, ultrasound has been used for BH treatment guidance and evaluation. The in vivo histopathological effects of this treatment are largely unknown. Here, we report on an MR guided BH method to treat subcutaneous tumors in a mouse model. The treatment effects of BH were evaluated one hour and four days later with MRI and histopathology, and compared with the effects of thermal HIFU (T-HIFU). The lesions caused by BH were easily detected with T2 w imaging as a hyper-intense signal area with a hypo-intense rim. Histopathological evaluation showed that the targeted tissue was completely disintegrated and that a narrow transition zone (<200 µm) containing many apoptotic cells was present between disintegrated and vital tumor tissue. A high level of agreement was found between T2 w imaging and H&E stained sections, making T2 w imaging a suitable method for treatment evaluation during or directly after BH. After T-HIFU, contrast enhanced imaging was required for adequate detection of the ablation zone. On histopathology, an ablation zone with concentric layers was seen after T-HIFU. In line with histopathology, contrast enhanced MRI revealed that after BH or T-HIFU perfusion within the lesion was absent, while after BH in the transition zone some micro-hemorrhaging appeared. Four days after BH, the transition zone with apoptotic cells was histologically no longer detectable, corresponding to the absence of a hypo-intense rim around the lesion in T2 w images. This study demonstrates the first results of in vivo BH on mouse tumor using MRI for treatment guidance and evaluation and opens the way for more detailed investigation of the in vivo effects of BH. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Allergies

MedlinePlus Videos and Cool Tools

Allergens like pollen are nothing more than foreign plant antigens. The stimulus for sneezing gets triggered when allergens first enter the nasal tissue. Pollen allergens encounter the plasma cells in the nose, ...

Comparison of patterns of allergen sensitization among inner-city Hispanic and African American children with asthma.

PubMed

Rastogi, Deepa; Reddy, Mamta; Neugebauer, Richard

2006-11-01

Among Hispanics, the largest minority ethnic group in the United States, asthma prevalence is increasing, particularly in inner-city neighborhoods. Although allergen sensitization among asthmatic African Americans has been extensively studied, similar details are not available for Hispanic children. To examine patterns of allergen sensitization, including the association with illness severity, in asthmatic children overall and in Hispanic and African American children living in a socioeconomically disadvantaged area of New York City. A retrospective medical record review of asthmatic children attending a community hospital in the South Bronx area of New York City was performed. Information abstracted included demographics, asthma severity classification, reported exposures to indoor allergens, and results of allergy testing. Among 384 children in the analysis, 270 (70.3%) were Hispanic and 114 (29.7%) were African American. Sensitization to indoor and outdoor allergens, respectively, did not differ between Hispanic (58.5% and 27.0%) and African American (58.8% and 32.6%) children. Allergen sensitization exhibited a direct, significant association with asthma severity for indoor allergens for the 2 ethnic groups combined and for Hispanics separately but not between asthma severity and outdoor allergens (P < .01). No correlation was found between self-reported allergen exposure and sensitization. Patterns of allergen sensitization among inner-city Hispanic asthmatic children resemble those among African American children, a finding that is likely explained by the similarity in levels of environmental exposures. With the increasing prevalence of asthma among inner-city Hispanic children, skin testing should be used frequently for objective evaluation of asthma in this ethnic group.

No Concentration Decrease of House Dust Mite Allergens With Rising Altitude in Alpine Regions

PubMed Central

Grafetstätter, Carina; Prossegger, Johanna; Braunschmid, Herbert; Sanovic, Renata; Hahne, Penelope; Pichler, Christina; Thalhamer, Josef

2016-01-01

Purpose Several studies over the past 4 decades have indicated a significant reduction in house dust mite (HDM) and HDM allergen concentration in areas higher than 1,500 m above sea level. These have served as basis of allergen avoidance therapies for HDM allergy and asthma. However, modern construction techniques used in the insulation, heating, and glazing of buildings as well as global warming have changed the environmental parameters for HDM living conditions. The present study revisits the paradigm of decreasing HDM allergen concentrations with increasing altitude in the alpine region of Germany and Austria. Methods A total of 122 dust samples from different abodes (hotels, privates and mountain huts) at different altitudes (400-2,600 m) were taken, and concentrations of HDM allergens were analyzed. Humidity and temperature conditions, and numerous indoor environmental parameters such as fine dust, type of flooring, age of building, and frequency of cleaning were determined. Results HDM allergen concentrations did not significantly change with increasing altitude or relative humidity. At the level of indoor parameters, correlations could be found for different flooring types and the concentration of HDM allergens. Conclusions In contrast to the widespread view of the relationship between altitude and HDM allergen concentrations, clinically relevant concentrations of HDM allergens could be detected in high-lying alpine regions in Austria and Germany. These results indicate that improvement in conditions of asthmatic patients sensitized against HDMs during a stay at high altitude can no longer be ascribed to decreased levels of HDM allergens, instead, other mechanisms may trigger the beneficial effect. PMID:27126724

No Concentration Decrease of House Dust Mite Allergens With Rising Altitude in Alpine Regions.

PubMed

Grafetstätter, Carina; Prossegger, Johanna; Braunschmid, Herbert; Sanovic, Renata; Hahne, Penelope; Pichler, Christina; Thalhamer, Josef; Hartl, Arnulf

2016-07-01

Several studies over the past 4 decades have indicated a significant reduction in house dust mite (HDM) and HDM allergen concentration in areas higher than 1,500 m above sea level. These have served as basis of allergen avoidance therapies for HDM allergy and asthma. However, modern construction techniques used in the insulation, heating, and glazing of buildings as well as global warming have changed the environmental parameters for HDM living conditions. The present study revisits the paradigm of decreasing HDM allergen concentrations with increasing altitude in the alpine region of Germany and Austria. A total of 122 dust samples from different abodes (hotels, privates and mountain huts) at different altitudes (400-2,600 m) were taken, and concentrations of HDM allergens were analyzed. Humidity and temperature conditions, and numerous indoor environmental parameters such as fine dust, type of flooring, age of building, and frequency of cleaning were determined. HDM allergen concentrations did not significantly change with increasing altitude or relative humidity. At the level of indoor parameters, correlations could be found for different flooring types and the concentration of HDM allergens. In contrast to the widespread view of the relationship between altitude and HDM allergen concentrations, clinically relevant concentrations of HDM allergens could be detected in high-lying alpine regions in Austria and Germany. These results indicate that improvement in conditions of asthmatic patients sensitized against HDMs during a stay at high altitude can no longer be ascribed to decreased levels of HDM allergens, instead, other mechanisms may trigger the beneficial effect.

Allergen concentration in natural rubber latex.

PubMed

Yeang, H-Y; Hamilton, R G; Bernstein, D I; Arif, S A M; Chow, K-S; Loke, Y-H; Raulf-Heimsoth, M; Wagner, S; Breiteneder, H; Biagini, R E

2006-08-01

Hevea brasiliensis latex serum is commonly used as the in vivo and in vitro reference antigen for latex allergy diagnosis as it contains the full complement of latex allergens. This study quantifies the concentrations of the significant allergens in latex serum and examines its suitability as an antigen source in latex allergy diagnosis and immunotherapy. The serum phase was extracted from centrifuged latex that was repeatedly freeze-thawed or glycerinated. Quantitation of latex allergens was performed by two-site immunoenzymetric assays. The abundance of RNA transcripts of the latex allergens was estimated from the number of their clones in an Expressed Sequence Tags library. The latex allergens, Hev b 1, 2, 3, 4, 5, 6, 7 and 13, were detected in freeze-thawed and glycerinated latex serum at levels ranging from 75 (Hev b 6) to 0.06 nmol/mg total proteins (Hev b 4). Hev b 6 content in the latex was up to a thousand times higher than the other seven latex allergens, depending on source and/or preparation procedure. Allergen concentration was reflected in the abundance of mRNA transcripts. When used as the antigen, latex serum may bias the outcome of latex allergy diagnostic tests towards sensitization to Hev b 6. Tests that make use of latex serum may fail to detect latex-specific IgE reactivity in subjects who are sensitized only to allergens that are present at low concentrations. Latex allergy diagnostics and immunotherapy that use whole latex serum as the antigen source may not be optimal because of the marked imbalance of its constituent allergens.

Is There a Threshold Concentration of Cat Allergen Exposure on Respiratory Symptoms in Adults?

PubMed Central

Zock, Jan-Paul; Villani, Simona; Olivieri, Mario; Modig, Lars; Jarvis, Deborah; Norbäck, Dan; Verlato, Giuseppe; Heinrich, Joachim

2015-01-01

Background and Objective Cat allergen concentrations higher than 8 μg/g in settled house dust, have been suggested to provoke exacerbation of allergic respiratory symptoms. However, whether the 8μg/g of indoor cat allergen concentration is indeed the minimal exposure required for triggering the asthma related respiratory symptoms or the development of sensitization has not yet been confirmed. We studied the associations between domestic cat allergen concentrations and allergic symptoms in the European Community Respiratory Health Survey II, with the aim of confirming this suggested threshold. Methods Cat allergen concentrations were measured in the mattress dust of 3003 participants from 22 study centres. Levels of specific immunoglobulin E to cat allergens were measured in serum samples using an immunoassay. Information on allergic symptoms, medication use, home environment and smoking was obtained from a face-to-face interview. Results Domestic cat allergen concentrations were not associated with allergic/ asthmatic symptoms in the entire study population, nor in the subset sensitized to cat allergen. We also found no association among individuals exposed to concentrations higher than 8 μg/g. However, exposure to medium cat allergen concentrations (0.24-0.63 μg/g) was positively associated with reported asthmatic respiratory symptoms in subjects who have experienced allergic symptoms when near animals. Conclusions The proposed 8 μg/g threshold of cat allergen concentrations for the exacerbation of allergic/ respiratory symptoms was not confirmed in a general European adult population. Potential biases attributable to avoidance behaviours and an imprecise exposure assessment cannot be excluded. PMID:26035304

Distribution of peanut allergen in the environment.

PubMed

Perry, Tamara T; Conover-Walker, Mary Kay; Pomés, Anna; Chapman, Martin D; Wood, Robert A

2004-05-01

Patients with peanut allergy can have serious reactions to very small quantities of peanut allergen and often go to extreme measures to avoid potential contact with this allergen. The purpose of this study was to detect peanut allergen under various environmental conditions and examine the effectiveness of cleaning agents for allergen removal. A monoclonal-based ELISA for Arachis hypogaea allergen 1 (Ara h 1; range of detection, 30-2000 ng/mL) was used to assess peanut contamination on cafeteria tables and other surfaces in schools, the presence of residual peanut protein after using various cleaning products on hands and tabletops, and airborne peanut allergen during the consumption of several forms of peanut. After hand washing with liquid soap, bar soap, or commercial wipes, Ara h 1 was undetectable. Plain water and antibacterial hand sanitizer left detectable Ara h 1 on 3 of 12 and 6 of 12 hands, respectively. Common household cleaning agents removed peanut allergen from tabletops, except dishwashing liquid, which left Ara h 1 on 4 of 12 tables. Of the 6 area preschools and schools evaluated, Ara h 1 was found on 1 of 13 water fountains, 0 of 22 desks, and 0 of 36 cafeteria tables. Airborne Ara h 1 was undetectable in simulated real-life situations when participants consumed peanut butter, shelled peanuts, and unshelled peanuts. The major peanut allergen, Ara h 1, is relatively easily cleaned from hands and tabletops with common cleaning agents and does not appear to be widely distributed in preschools and schools. We were not able to detect airborne allergen in many simulated environments.

High Environmental Ozone Levels Lead to Enhanced Allergenicity of Birch Pollen

PubMed Central

Beck, Isabelle; Jochner, Susanne; Gilles, Stefanie; McIntyre, Mareike; Buters, Jeroen T. M.; Schmidt-Weber, Carsten; Behrendt, Heidrun; Ring, Johannes; Menzel, Annette; Traidl-Hoffmann, Claudia

2013-01-01

Background Evidence is compelling for a positive correlation between climate change, urbanisation and prevalence of allergic sensitisation and diseases. The reason for this association is not clear to date. Some data point to a pro-allergenic effect of anthropogenic factors on susceptible individuals. Objectives To evaluate the impact of urbanisation and climate change on pollen allergenicity. Methods Catkins were sampled from birch trees from different sites across the greater area of Munich, pollen were isolated and an urbanisation index, NO2 and ozone exposure were determined. To estimate pollen allergenicity, allergen content and pollen-associated lipid mediators were measured in aqueous pollen extracts. Immune stimulatory and modulatory capacity of pollen was assessed by neutrophil migration assays and the potential of pollen to inhibit dendritic cell interleukin-12 response. In vivo allergenicity was assessed by skin prick tests. Results The study revealed ozone as a prominent environmental factor influencing the allergenicity of birch pollen. Enhanced allergenicity, as assessed in skin prick tests, was mirrored by enhanced allergen content. Beyond that, ozone induced changes in lipid composition and chemotactic and immune modulatory potential of the pollen. Higher ozone-exposed pollen was characterised by less immune modulatory but higher immune stimulatory potential. Conclusion It is likely that future climate change along with increasing urbanisation will lead to rising ozone concentrations in the next decades. Our study indicates that ozone is a crucial factor leading to clinically relevant enhanced allergenicity of birch pollen. Thus, with increasing temperatures and increasing ozone levels, also symptoms of pollen allergic patients may increase further. PMID:24278250

Molecular Evolution of Hypoallergenic Hybrid Proteins for Vaccination against Grass Pollen Allergy

PubMed Central

Linhart, Birgit; Focke-Tejkl, Margarete; Weber, Milena; Narayanan, Meena; Neubauer, Angela; Mayrhofer, Hannes; Blatt, Katharina; Lupinek, Christian; Valent, Peter

2015-01-01

More than 10% of the population in Europe and North America suffer from IgE-associated allergy to grass pollen. In this article, we describe the development of a vaccine for grass pollen allergen-specific immunotherapy based on two recombinant hypoallergenic mosaic molecules, designated P and Q, which were constructed out of elements derived from the four major timothy grass pollen allergens: Phl p 1, Phl p 2, Phl p 5, and Phl p 6. Seventeen recombinant mosaic molecules were expressed and purified in Escherichia coli using synthetic genes, characterized regarding biochemical properties, structural fold, and IgE reactivity. We found that depending on the arrangement of allergen fragments, mosaic molecules with strongly varying IgE reactivity were obtained. Based on an extensive screening with sera and basophils from allergic patients, two hypoallergenic mosaic molecules, P and Q, incorporating the primary sequence elements of the four grass pollen allergens were identified. As shown by lymphoproliferation experiments, they contained allergen-specific T cell epitopes required for tolerance induction, and upon immunization of animals induced higher allergen-specific IgG Abs than the wild-type allergens and a registered monophosphoryl lipid A–adjuvanted vaccine based on natural grass pollen allergen extract. Moreover, IgG Abs induced by immunization with P and Q inhibited the binding of patients’ IgE to natural allergens from five grasses better than IgG induced with the wild-type allergens or an extract-based vaccine. Our results suggest that vaccines based on the hypoallergenic grass pollen mosaics can be used for immunotherapy of grass pollen allergy. PMID:25786690

Rational design of hypoallergens applied to the major cat allergen Fel d 1.

PubMed

Saarne, T; Kaiser, L; Grönlund, H; Rasool, O; Gafvelin, G; van Hage-Hamsten, M

2005-05-01

Allergen-specific immunotherapy is the only treatment for allergic disease providing long-lasting symptom relief. Currently, it is mainly based on the use of crude allergen extracts. The treatment may be improved by the use of genetically engineered allergens, hypoallergens, aiming at a more effective and safer therapy. The aim of this study was to provide a rational design of hypoallergen candidates for immunotherapy by using structural information and knowledge of B and T cell epitopes of an allergen. The three-dimensional structure of the major cat allergen Fel d 1 was systematically altered by duplication of selected T cell epitopes and disruption of disulphide bonds. Seven Fel d 1 derivatives were generated and screened for allergenic reactivity in comparison with recombinant Fel d 1 in competition-ELISA. The allergenicity was further evaluated in basophil activation experiments and T cell reactivity was assessed in a lymphoproliferation assay. Three out of seven Fel d 1 derivatives, with two duplicated T cell epitopes and one or two disulphide bonds disrupted, were carefully evaluated. The three derivatives displayed a strong reduction in allergenicity with 400-900 times lower IgE-binding capacity than recombinant Fel d 1. In addition, they induced a lower degree of basophil activation and similar or stronger T cell proliferation than recombinant Fel d 1. By a rational approach, we have constructed three Fel d 1 hypoallergens with reduced IgE-binding capacities and retained T cell reactivities. This strategy may be applied to any well-characterized allergen to improve immunotherapy for allergic patients.

AllergenFP: allergenicity prediction by descriptor fingerprints.

PubMed

Dimitrov, Ivan; Naneva, Lyudmila; Doytchinova, Irini; Bangov, Ivan

2014-03-15

Allergenicity, like antigenicity and immunogenicity, is a property encoded linearly and non-linearly, and therefore the alignment-based approaches are not able to identify this property unambiguously. A novel alignment-free descriptor-based fingerprint approach is presented here and applied to identify allergens and non-allergens. The approach was implemented into a four step algorithm. Initially, the protein sequences are described by amino acid principal properties as hydrophobicity, size, relative abundance, helix and β-strand forming propensities. Then, the generated strings of different length are converted into vectors with equal length by auto- and cross-covariance (ACC). The vectors were transformed into binary fingerprints and compared in terms of Tanimoto coefficient. The approach was applied to a set of 2427 known allergens and 2427 non-allergens and identified correctly 88% of them with Matthews correlation coefficient of 0.759. The descriptor fingerprint approach presented here is universal. It could be applied for any classification problem in computational biology. The set of E-descriptors is able to capture the main structural and physicochemical properties of amino acids building the proteins. The ACC transformation overcomes the main problem in the alignment-based comparative studies arising from the different length of the aligned protein sequences. The conversion of protein ACC values into binary descriptor fingerprints allows similarity search and classification. The algorithm described in the present study was implemented in a specially designed Web site, named AllergenFP (FP stands for FingerPrint). AllergenFP is written in Python, with GIU in HTML. It is freely accessible at http://ddg-pharmfac.net/Allergen FP. idoytchinova@pharmfac.net or ivanbangov@shu-bg.net.

The principle of homologous groups in regulatory affairs of allergen products--a proposal.

PubMed

Lorenz, A R; Lüttkopf, D; May, S; Scheurer, S; Vieths, S

2009-01-01

Among other legal regulations, the Note for Guidance on Allergen Products CPMP/BWP/243/96 released by the European Medicines Agency provides regulatory instructions regarding the quality of allergen extracts for diagnostic or therapeutic purposes. The current revision of this guideline intends to transform the so-called 'principle of taxonomic families' to the 'principle of homologous groups'. According to this concept, the data of one allergen extract demonstrating stability, efficacy and safety can, to a limited extent, be extrapolated to other allergen extracts belonging to the same homologous groups. The present work proposes the formation of homologous groups for pollen species and animal-derived materials on the basis of similar biochemical composition and homology/cross-reactivity of allergens or allergen sources. Some tree pollen species could be assigned to three different homologous groups, some weed pollen species to one homologous group and numerous grass pollen species to one homologous group on condition that data rely on single defined representative species. A homologous group for mites is limited to the Dermatophagoides species and the grouping of vertebrate-derived materials such as dander could be possible under restrictions. The criteria for the formation of the proposed homologous groups are illustrated in detail to provide an opportunity for extending existing homologous groups by further species in case of new insights in allergens and cross-reactivity of allergen sources. In this way, the concept of homologous groups could serve as a dynamic tool in the regulation of allergen products. (c) 2008 S. Karger AG, Basel.

Rapid allergen-induced interleukin-17 and interferon-γ secretion by skin-resident memory CD8+ T cells.

PubMed

Schmidt, Jonas D; Ahlström, Malin G; Johansen, Jeanne D; Dyring-Andersen, Beatrice; Agerbeck, Christina; Nielsen, Morten M; Poulsen, Steen S; Woetmann, Anders; Ødum, Niels; Thomsen, Allan R; Geisler, Carsten; Bonefeld, Charlotte M

2017-04-01

Skin-resident memory T (T RM ) cells are associated with immunological memory in the skin. Whether immunological memory responses to allergens in the skin are solely localized to previously allergen-exposed sites or are present globally in the skin is not clear. Furthermore, the mechanisms whereby T RM cells induce rapid recall responses need further investigation. To study whether contact allergens induce local and/or global memory, and to determine the mechanisms involved in memory responses in the skin. To address these questions, we analysed responses to contact allergens in mice and humans sensitized to 2,4-dinitrofluorobenzene and nickel, respectively. Challenge responses in both mice and humans were dramatically increased at sites previously exposed to allergens as compared with previously unexposed sites. Importantly, the magnitude of the challenge response correlated with the epidermal accumulation of interleukin (IL)-17A-producing and interferon (IFN)-γ-producing T RM cells. Moreover, IL-17A and IFN-γ enhanced allergen-induced IL-1β production in keratinocytes. We show that sensitization with contact allergens induces a strong, long-lasting local memory and a weaker, temporary global immunological memory response to the allergen that is mediated by IL-17A-producing and IFN-γ-producing CD8 + T RM cells. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Sensitization to common allergens among patients with allergies in major Iranian cities: a systematic review and meta-analysis.

PubMed

Moghtaderi, Mozhgan; Hosseini Teshnizi, Saeed; Farjadian, Shirin

2017-01-01

Various allergens are implicated in the pathogenesis of allergic diseases in different regions. This study attempted to identify the most common allergens among patients with allergies based on the results of skin prick tests in different parts of Iran. Relevant studies conducted from 2000 to 2016 were identified from the MEDLINE database. Six common groups of allergen types, including animal, cockroach, food, fungus, house dust mite, and pollen were considered. Subgroup analysis was performed to determine the prevalence of each type of allergen. The Egger test was used to assess publication bias. We included 44 studies in this meta-analysis. The overall prevalence of positive skin test results for at least one allergen was estimated to be 59% in patients with allergies in various parts of Iran. The number of patients was 11,646 (56% male and 44% female), with a mean age of 17.46±11.12 years. The most common allergen sources were pollen (47.0%), mites (35.2%), and food (15.3%). The prevalence of sensitization to food and cockroach allergens among children was greater than among adults. Pollen is the most common allergen sensitization in cities of Iran with a warm and dry climate; however, sensitization to house dust mites is predominant in northern and southern coastal areas of Iran.

Sensitization to common allergens among patients with allergies in major Iranian cities: a systematic review and meta-analysis

PubMed Central

Farjadian, Shirin

2017-01-01

Various allergens are implicated in the pathogenesis of allergic diseases in different regions. This study attempted to identify the most common allergens among patients with allergies based on the results of skin prick tests in different parts of Iran. Relevant studies conducted from 2000 to 2016 were identified from the MEDLINE database. Six common groups of allergen types, including animal, cockroach, food, fungus, house dust mite, and pollen were considered. Subgroup analysis was performed to determine the prevalence of each type of allergen. The Egger test was used to assess publication bias. We included 44 studies in this meta-analysis. The overall prevalence of positive skin test results for at least one allergen was estimated to be 59% in patients with allergies in various parts of Iran. The number of patients was 11,646 (56% male and 44% female), with a mean age of 17.46±11.12 years. The most common allergen sources were pollen (47.0%), mites (35.2%), and food (15.3%). The prevalence of sensitization to food and cockroach allergens among children was greater than among adults. Pollen is the most common allergen sensitization in cities of Iran with a warm and dry climate; however, sensitization to house dust mites is predominant in northern and southern coastal areas of Iran. PMID:28171712

[The clinical efficacy of allergen-specific immunotherapy with water-salt extracts and adjuvant allergens for atopic asthma with household sensitization].

PubMed

Ushakova, D V; Nikonov, E L

To evaluate the clinical and economic efficiency of allergen-specific immunotherapy (ASIT); to comparatively analyze the efficiency of various therapy regimens for atopic asthma. The clinical and economic efficiency of asthma therapy using ASIT with water-salt allergen extracts or the adjuvant drug alustal 'mite allergen' and only with medicines were comparatively analyzed. The investigation enrolled 156 patients with mild and moderate atopic asthma, household allergy. In Group 1 (n = 57), ASIT was performed using the classical scheme by subcutaneous injection of house dust mite allergen (JSC 'I.I. Mechnikov Biomed', Russia). In Group 2 (n = 43), ASIT was conducted using the alustal 'mite allergen' (Stallergenes, France). Group 3 (n = 56) received only medical therapy. ASIT with both water-salt allergen extracts and the adjuvant allergen alustal is an effective treatment for mild and moderate atopic asthma. ASIT greatly reduces the need for anti-inflammatory treatment and the use of symptomatic drugs and improves the physical and psychoemotional indicators of quality of life in patients. The economic benefit of ASIT is delayed, but its use significantly reduces financing costs. ASIT is a reasonable, highly effective and ultimately cost-effective treatment in patients with atopic asthma. A variety of drugs for ASIT can choose schemes that are convenient and acceptable for each patient, which allows wider use of this treatment.

Managing Food Allergens in the U.K. Retail Supply Chain.

PubMed

Walker, Michael J; Gowland, M Hazel; Points, John

2018-01-01

The U.K. food and grocery market is highly significant financially and dominated by 10 retailers within a regulated and extremely economically competitive environment. We summarize the approach of U.K. retailers to allergen risk assessment (RA) and risk management (RM) within the U.K. legal framework and explore public visibility of retailers' allergen policies. RA and RM of allergens appear effective in curtailing retail-triggered severe food allergy reactions. However, allergen recalls remain high, precautionary allergen labeling (PAL) remains an area of confusion, and there is no consistent Web-based provision of information for consumers who have allergies. Resolution of PAL awaits an agreed-on threshold framework, but a key challenge is to engage with patients and gain their trust rather than thrust education at them. It would be helpful for retailers to publish their allergen RA and RM policies. A target should be agreed on between government and retailers for a reduction in the proliferation of PAL wording variants by a given date within the next 3 years. A further hurdle is potentially flawed allergen analysis-development of reference methods and reference materials are acknowledged needs. Laboratories should report allergen results in an informative manner, communicating uncertainty and caveats. Ideally a laboratory representative would be included on any incident control team. Efforts must continue to standardize preparedness for protecting and defending food and drink from deliberate attack.

ImmunoCAP assays: Pros and cons in allergology.

PubMed

van Hage, Marianne; Hamsten, Carl; Valenta, Rudolf

2017-10-01

Allergen-specific IgE measurements and the clinical history are the cornerstones of allergy diagnosis. During the past decades, both characterization and standardization of allergen extracts and assay technology have improved. Here we discuss the uses, advantages, misinterpretations, and limitations of ImmunoCAP IgE assays (Thermo Fisher Scientific/Phadia, Uppsala, Sweden) in the field of allergology. They can be performed as singleplex (ImmunoCAP) and, for the last decade, as multiplex (Immuno Solid-phase Allergen Chip [ISAC]). The major benefit of ImmunoCAP is the obtained quantified allergen-specific IgE antibody level and the lack of interference from allergen-specific IgG antibodies. However, ImmunoCAP allergen extracts are limited to the composition of the extract. The introduction of allergen molecules has had a major effect on analytic specificity and allergy diagnosis. They are used in both singleplex ImmunoCAP and multiplex ImmunoCAP ISAC assays. The major advantage of ISAC is the comprehensive IgE pattern obtained with a minute amount of serum. The shortcomings are its semiquantitative measurements, lower linear range, and cost per assay. With respect to assay performance, ImmunoCAP allergen extracts are good screening tools, but allergen molecules dissect the IgE response on a molecular level and put allergy research on the map of precision medicine. Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Precautionary labelling of foods for allergen content: are we ready for a global framework?

PubMed

Allen, Katrina J; Turner, Paul J; Pawankar, Ruby; Taylor, Stephen; Sicherer, Scott; Lack, Gideon; Rosario, Nelson; Ebisawa, Motohiro; Wong, Gary; Mills, E N Clare; Beyer, Kirsten; Fiocchi, Alessandro; Sampson, Hugh A

2014-01-01

Food allergy appears to be on the rise with the current mainstay of treatment centred on allergen avoidance. Mandatory allergen labelling has improved the safety of food for allergic consumers. However an additional form of voluntary labelling (termed precautionary allergen labelling) has evolved on a wide range of packaged goods, in a bid by manufacturers to minimise risk to customers, and the negative impact on business that might result from exposure to trace amounts of food allergen present during cross-contamination during production. This has resulted in near ubiquitous utilisation of a multitude of different precautionary allergen labels with subsequent confusion amongst many consumers as to their significance. The global nature of food production and manufacturing makes harmonisation of allergen labelling regulations across the world a matter of increasing importance. Addressing inconsistencies across countries with regards to labelling legislation, as well as improvement or even banning of precautionary allergy labelling are both likely to be significant steps forward in improved food safety for allergic families. This article outlines the current status of allergen labelling legislation around the world and reviews the value of current existing precautionary allergen labelling for the allergic consumer. We strongly urge for an international framework to be considered to help roadmap a solution to the weaknesses of the current systems, and discuss the role of legislation in facilitating this.

Dust Allergens within Rural Northern Rocky Mountain Residences.

PubMed

Weiler, Emily; Semmens, Erin; Noonan, Curtis; Cady, Carol; Ward, Tony

2015-01-23

To date, few studies have characterized allergens within residences located in rural areas of the northern Rocky Mountain region. In this study, we collected dust samples from 57 homes located throughout western Montana and northern Idaho. Dust samples were collected and later analyzed for dust mite allergens Der f 1 and Der p 1 , Group 2 mite allergens ( Der p 2 and Der f 2 ), domestic feline ( Fel d 1 ), and canine ( Can f 1 ). Indoor temperature and humidity levels were also measured during the sampling program, as were basic characteristics of each home. Dog (96%) and cat (82%) allergens were the most prevalent allergens found in these homes (even when a feline or canine did not reside in the home). Results also revealed the presence of dust mites. Seven percent (7%) of homes tested positive for Der p 1 , 19% of homes were positive for Der f 1 , and 5% of homes were positive for the Group 2 mite allergens. Indoor relative humidity averaged 27.0 ± 7.6% within the homes. Overall, humidity was not significantly associated with dust mite presence, nor was any of the other measured home characteristics. This study provides a descriptive assessment of indoor allergen presence (including dust mites) in rural areas of the northern Rocky Mountains, and provides new information to assist regional patients with reducing allergen exposure using in-home intervention strategies.

Precautionary labelling of foods for allergen content: are we ready for a global framework?

PubMed Central

2014-01-01

Food allergy appears to be on the rise with the current mainstay of treatment centred on allergen avoidance. Mandatory allergen labelling has improved the safety of food for allergic consumers. However an additional form of voluntary labelling (termed precautionary allergen labelling) has evolved on a wide range of packaged goods, in a bid by manufacturers to minimise risk to customers, and the negative impact on business that might result from exposure to trace amounts of food allergen present during cross-contamination during production. This has resulted in near ubiquitous utilisation of a multitude of different precautionary allergen labels with subsequent confusion amongst many consumers as to their significance. The global nature of food production and manufacturing makes harmonisation of allergen labelling regulations across the world a matter of increasing importance. Addressing inconsistencies across countries with regards to labelling legislation, as well as improvement or even banning of precautionary allergy labelling are both likely to be significant steps forward in improved food safety for allergic families. This article outlines the current status of allergen labelling legislation around the world and reviews the value of current existing precautionary allergen labelling for the allergic consumer. We strongly urge for an international framework to be considered to help roadmap a solution to the weaknesses of the current systems, and discuss the role of legislation in facilitating this. PMID:24791183

Comparison between Newly Developed and Commercial Inhalant Skin Prick Test Reagents Using In Vivo and In Vitro Methods

PubMed Central

2018-01-01

Background We developed skin prick test (SPT) reagents for common inhalant allergens that reflected the real exposure in Korea. The study aim was to evaluate diagnostic usefulness and allergen potency of our inhalant SPT reagents in comparison with commercial products. Methods We produced eight common inhalant allergen SPT reagents using total extract (Prolagen): Dermatophagoides farinae, Dermatophagoides pteronyssinus, oak, ragweed, mugwort, Humulus japonicus pollens, as well as cat and dog allergens. We compared the newly developed reagents with three commercially available SPT reagents (Allergopharma, Hollister-Stier, Lofarma). We measured total protein concentrations, sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), major allergen concentration, and biological allergen potencies measured by immunoglobulin E (IgE) immunoblotting and ImmunoCAP inhibition test. Results Diagnostic values of these SPT reagents were expressed as positivity rate and concordance rate of the results from ImmunoCAP allergen-specific IgE test in 94 allergic patients. In vitro analysis showed marked differences in protein concentrations, SDS-PAGE features, major allergen concentrations, and biological allergen potencies of four different SPT reagents. In vivo analysis showed that positive rates and concordance rates of Prolagen® SPT reagents were similar compared to the three commercial SPT reagents. Conclusion The newly developed Prolagen® inhalant SPT reagents are not inferior to the commercially available SPT reagents in allergy diagnosis. PMID:29573248

PREAL: prediction of allergenic protein by maximum Relevance Minimum Redundancy (mRMR) feature selection

PubMed Central

2013-01-01

Background Assessment of potential allergenicity of protein is necessary whenever transgenic proteins are introduced into the food chain. Bioinformatics approaches in allergen prediction have evolved appreciably in recent years to increase sophistication and performance. However, what are the critical features for protein's allergenicity have been not fully investigated yet. Results We presented a more comprehensive model in 128 features space for allergenic proteins prediction by integrating various properties of proteins, such as biochemical and physicochemical properties, sequential features and subcellular locations. The overall accuracy in the cross-validation reached 93.42% to 100% with our new method. Maximum Relevance Minimum Redundancy (mRMR) method and Incremental Feature Selection (IFS) procedure were applied to obtain which features are essential for allergenicity. Results of the performance comparisons showed the superior of our method to the existing methods used widely. More importantly, it was observed that the features of subcellular locations and amino acid composition played major roles in determining the allergenicity of proteins, particularly extracellular/cell surface and vacuole of the subcellular locations for wheat and soybean. To facilitate the allergen prediction, we implemented our computational method in a web application, which can be available at http://gmobl.sjtu.edu.cn/PREAL/index.php. Conclusions Our new approach could improve the accuracy of allergen prediction. And the findings may provide novel insights for the mechanism of allergies. PMID:24565053

Simple methods to reduce major allergen Ara h 1 and Ana o 1/2 in peanut and cashew extracts

USDA-ARS?s Scientific Manuscript database

Whole peanut extracts are usually used in immunotherapy but may have side effects. Reducing major peanut allergen(s) in the extracts may reduce the side effects. Three simple methods were evaluated to reduce major allergen Ara h 1 from a peanut extract: (1) treatment with p-aminobenzamidine (pABA); ...

Group 10 allergens (tropomyosins) from house-dust mites may cause covariation of sensitization to allergens from other invertebrates

PubMed Central

Inam, Muhammad; Ismail, Muhammad; Chaudhary, Farhana Riaz

2012-01-01

Group 10 allergens (tropomyosins) have been assumed to be a major cause of cross-reactivity between house-dust mites (HDMs) and other invertebrates. Despite all of the published data regarding the epidemiology, percent IgE binding and level of sensitization in the population, the role of tropomyosin as a cross-reactive allergen in patients with multiple allergy syndrome still remains to be elucidated. Homology between amino acid sequences reported in allergen databases of selected invertebrate tropomyosins was determined with Der f 10 as the reference allergen. The 66.9 and 54.4% identities were found with selected crustacean and insect species, respectively, whereas only 20.4% identity was seen with mollusks. A similar analysis was performed using reported B-cell IgE-binding epitopes from Met e1 (shrimp allergen) and Bla g7 (cockroach allergen) with other invertebrate tropomyosins. The percent identity in linear sequences was higher than 35% in mites, crustaceans, and cockroaches. The polar and hydrophobic regions in these groups were highly conserved. These findings suggest that tropomyosin may be a major cause of covariation of sensitization between HDMs, crustaceans, and some species of insects and mollusks. PMID:23342293

Study of quantitative changes of cereal allergenic proteins after food processing.

PubMed

Flodrová, Dana; Benkovská, Dagmar; Laštovičková, Markéta

2015-03-30

Within last few years, the occurrence of food allergens and corresponding food allergies has been increasing, therefore research into the individual allergens is required. In the present work, the effect of cereal processing on the amounts of allergenic proteins is studied by modern proteomic-based approaches. The most important wheat and barley allergens are low-molecular-weight (LMW) proteins. Therefore we investigated the relative quantitative changes of these proteins after food technological processing, namely wheat couscous production and barley malting. A comparative study using mass spectrometry in connection with the technique of isobaric tag for relative and absolute quantification (iTRAQ) revealed that the amount of wheat allergenic LMW proteins decreased significantly during couscous production (approximately to 5-26% of their initial content in wheat flour). After barley malting, the amounts of the majority of LMW proteins decreased as well, although to a lesser extent than in the case of wheat/couscous. The level of two allergens even slightly increased. Suggested proteomic strategy proved as universal and sensitive method for fast and reliable identification of various cereal allergens and monitoring of their quantitative changes during food processing. Such information is important for consumers who suffer from allergies. © 2014 Society of Chemical Industry.

Food aversion: a critical balance between allergen-specific IgE levels and taste preference.

PubMed

Mirotti, Luciana; Mucida, Daniel; de Sá-Rocha, Luis Carlos; Costa-Pinto, Frederico Azevedo; Russo, Momtchilo

2010-03-01

Animals sensitized to allergens change their feeding behavior and avoid drinking the otherwise preferred sweetened solutions containing the allergens. This phenomenon, known as food aversion, appears to be mediated by allergen-specific IgE antibodies. Here we investigated food aversion in BALB/c and C57BL/6 mice, which differ in their allergic responses to the allergen ovalbumin as well as in their preference for sweet taste. BALB/c mice present higher levels of IgE and a natural lower preference for sweet flavors when compared to C57BL/6 mice. Specifically, we studied a conflicting situation in which animals simultaneously experienced the aversive contact with the allergen and the attractive sweet taste of increasing concentrations of sucrose. We found that BALB/c mice were more prone to develop food aversion than C57BL/6 mice and that this aversive behavior could be abolished in both strains by increasing the palatability of the solution containing the allergen. In both strains food aversion was positively correlated with the levels of allergen-specific IgE antibodies and inversely correlated with their preference for sucrose sweetened solutions. 2009 Elsevier Inc. All rights reserved.

[The use of Russian allergoids for the specific immunotherapy of pollinosis].

PubMed

Fradkin, V A; Roshal', N I; Goriachkina, L A; Nikonorova, M V; Astaf'eva, N G; Luss, L V; Raĭkis, V N

1993-01-01

For three years 128 pollinosis patients received specific immunotherapy with cereals, weed and tree pollen allergens manufactured by the Scientific and Industrial Amalgamation "Allergen" (Stavropol). For comparison, a group of 42 patients was treated with the corresponding allergens according to the commonly used treatment scheme. Patients who had earlier undergone treatment with water-saline extracts of allergens, that proved to be ineffective, formed a special group. In sensitive patients reaction to the skin test with allergoids was by half less pronounced than reaction to the skin test with allergens. In allergometric titration on the nasal mucosa, reaction to the introduction of allergoids could be registered when they were used at a 10- to 100-fold higher concentration than allergens. The course of specific immunotherapy with allergoids was found to lead to a decrease in the level of allergen-specific IgE antibodies (p > 0.05) and total IgE (p < 0.01). An increase in the level of IgG antibodies was noted (p < 0.01). Specific immunotherapy with allergoids was more effective than that with water-saline extracts of allergens. The use of allergoids made it possible to prescribe specific immunotherapy to a wider circle of patients.

Allergen immunotherapy in allergic rhinitis: current use and future trends.

PubMed

Klimek, Ludger; Pfaar, Oliver; Bousquet, Jean; Senti, Gabriela; Kündig, Thomas

2017-09-01

Type-1 allergies are among the most chronic common diseases of humans. Allergen immunotherapy (AIT) is the only causative and disease-modifying treatment option besides allergen avoidance. Severe systemic adverse allergic reactions may be induced by every AIT treatment. Different approaches have been used to provide safer AIT preparations to lower or even totally overcome this risk. Areas covered: A structured literature recherche in Medline and Pubmed under inclusion of national and international guidelines and Cochrane meta-analyses has been performed aiming at reviewing clinical use of such approaches in AIT. New allergen preparations may include allergoids, recombinant allergens (recA) and modified recombinant allergens (recA) in subcutaneous as well as in mucosal immunotherapies (application e.g. using bronchial, nasal, oral and sublingual application) with sublingual being the established mucosal application route and new ways of application like intralymphatic and epicutaneous immunotherapy. Expert commentary: Immune-modifying agents like Virus-like particles and CpG-motifs, adjuvants like MPL and aluminum hydroxide are evaluated and found to increase and direct the immunological response toward immunological tolerance. New forms of allergen extracts can improve safety and efficacy of AIT and may change our way of performing allergen immunotherapy in the future.

Structural analysis of linear and conformational epitopes of allergens

PubMed Central

Ivanciuc, Ovidiu; Schein, Catherine H.; Garcia, Tzintzuni; Oezguen, Numan; Negi, Surendra S.; Braun, Werner

2009-01-01

In many countries regulatory agencies have adopted safety guidelines, based on bioinformatics rules from the WHO/FAO and EFSA recommendations, to prevent potentially allergenic novel foods or agricultural products from reaching consumers. We created the Structural Database of Allergenic Proteins (SDAP, http://fermi.utmb.edu/SDAP/) to combine data that had previously been available only as flat files on Web pages or in the literature. SDAP was designed to be user friendly, to be of maximum use to regulatory agencies, clinicians, as well as to scientists interested in assessing the potential allergenic risk of a protein. We developed methods, unique to SDAP, to compare the physicochemical properties of discrete areas of allergenic proteins to known IgE epitopes. We developed a new similarity measure, the property distance (PD) value that can be used to detect related segments in allergens with clinical observed crossreactivity. We have now expanded this work to obtain experimental validation of the PD index as a quantitative predictor of IgE cross-reactivity, by designing peptide variants with predetermined PD scores relative to known IgE epitopes. In complementary work we show how sequence motifs characteristic of allergenic proteins in protein families can be used as fingerprints for allergenicity. PMID:19121639

Prioritisation of allergenic foods with respect to public health relevance: Report from an ILSI Europe Food Allergy Task Force Expert Group.

PubMed

Houben, Geert; Burney, Peter; Chan, Chun-Han; Crevel, René; Dubois, Anthony; Faludi, Roland; Klein Entink, Rinke; Knulst, André; Taylor, Steve; Ronsmans, Stefan

2016-03-01

Regulators and risk managers in general need to decide whether an allergenic food or ingredient is of such public health importance that it needs to be actively managed. There is therefore a need to scale the relative allergenicity of foods and ingredients according to the hazards they pose. Objective criteria increase transparency and trust in this decision-making process and its conclusions. This paper proposes a framework that allows categorisation and prioritisation of allergenic foods according to their public health importance. The challenge is to find a basis on which the allergenicity of foods can best be described and a method to combine the relevant measures of allergenicity into a scoring system that prioritises allergenic foods on the basis of their public health relevance. The framework is designed in accordance with the generic risk analysis principles used in food safety and can be used by regulators to decide whether or not a specific allergenic food or ingredient is of sufficient public health importance that it warrants regulation (i.e. mandatory labelling) when used in the production of food products. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Advanced DNA- and Protein-based Methods for the Detection and Investigation of Food Allergens.

PubMed

Prado, M; Ortea, I; Vial, S; Rivas, J; Calo-Mata, P; Barros-Velázquez, J

2016-11-17

Currently, food allergies are an important health concern worldwide. The presence of undeclared allergenic ingredients or the presence of traces of allergens due to contamination during food processing poses a great health risk to sensitized individuals. Therefore, reliable analytical methods are required to detect and identify allergenic ingredients in food products. The present review addresses the recent developments regarding the application of DNA- and protein-based methods for the detection of allergenic ingredients in foods. The fitness-for-purpose of reviewed methodology will be discussed, and future trends will be highlighted. Special attention will be given to the evaluation of the potential of newly developed and promising technologies that can improve the detection and identification of allergenic ingredients in foods, such as the use of biosensors and/or nanomaterials to improve detection limits, specificity, ease of use, or to reduce the time of analysis. Such rapid food allergen test methods are required to facilitate the reliable detection of allergenic ingredients by control laboratories, to give the food industry the means to easily determine whether its product has been subjected to cross-contamination and, simultaneously, to identify how and when this cross-contamination occurred.

Workshop proceedings: challenges and opportunities in evaluating protein allergenicity across biotechnology industries.

PubMed

Stagg, Nicola J; Ghantous, Hanan N; Ladics, Gregory S; House, Robert V; Gendel, Steven M; Hastings, Kenneth L

2013-01-01

A workshop entitled "Challenges and Opportunities in Evaluating Protein Allergenicity across Biotechnology Industries" was held at the 51st Annual Meeting of the Society of Toxicology (SOT) in San Francisco, California. The workshop was sponsored by the Biotechnology Specialty Section of SOT and was designed to present the science-based approaches used in biotechnology industries to evaluate and regulate protein allergenicity. A panel of experts from industry and government highlighted the allergenicity testing requirements and research in the agricultural, pharmaceutical/biopharma, and vaccine biotechnology industries and addressed challenges and opportunities for advancing the science of protein allergenicity. The main learning from the workshop was that immunoglobulin E-mediated allergenicity of biotechnology-derived products is difficult to assess without human data. The approaches currently being used to evaluate potential for allergenicity across biotechnology industries are very different and range from bioinformatics, in vitro serology, in vivo animal testing, in vitro and in vivo functional assays, and "biosimilar" assessments (ie, biotherapeutic equivalents to innovator products). The challenge remains with regard to the different or lack of regulatory requirements for allergenicity testing across industries, but the novel approaches being used with bioinformatics and biosimilars may lead to opportunities in the future to collaborate across biotechnology industries.

Role of M2 Muscarinic Receptor in the Airway Response to Methacholine of Mice Selected for Minimal or Maximal Acute Inflammatory Response

PubMed Central

Castro, Juciane Maria de Andrade; Resende, Rodrigo R.; Florsheim, Esther; Albuquerque, Layra Lucy; Lino-dos-Santos-Franco, Adriana; Gomes, Eliane; Tavares de Lima, Wothan; de Franco, Marcelo; Ribeiro, Orlando Garcia

2013-01-01

Airway smooth muscle constriction induced by cholinergic agonists such as methacholine (MCh), which is typically increased in asthmatic patients, is regulated mainly by muscle muscarinic M3 receptors and negatively by vagal muscarinic M2 receptors. Here we evaluated basal (intrinsic) and allergen-induced (extrinsic) airway responses to MCh. We used two mouse lines selected to respond maximally (AIRmax) or minimally (AIRmin) to innate inflammatory stimuli. We found that in basal condition AIRmin mice responded more vigorously to MCh than AIRmax. Treatment with a specific M2 antagonist increased airway response of AIRmax but not of AIRmin mice. The expression of M2 receptors in the lung was significantly lower in AIRmin compared to AIRmax animals. AIRmax mice developed a more intense allergic inflammation than AIRmin, and both allergic mouse lines increased airway responses to MCh. However, gallamine treatment of allergic groups did not affect the responses to MCh. Our results confirm that low or dysfunctional M2 receptor activity is associated with increased airway responsiveness to MCh and that this trait was inherited during the selective breeding of AIRmin mice and was acquired by AIRmax mice during allergic lung inflammation. PMID:23691511

EVALLER: a web server for in silico assessment of potential protein allergenicity

PubMed Central

Barrio, Alvaro Martinez; Soeria-Atmadja, Daniel; Nistér, Anders; Gustafsson, Mats G.; Hammerling, Ulf; Bongcam-Rudloff, Erik

2007-01-01

Bioinformatics testing approaches for protein allergenicity, involving amino acid sequence comparisons, have evolved appreciably over the last several years to increased sophistication and performance. EVALLER, the web server presented in this article is based on our recently published ‘Detection based on Filtered Length-adjusted Allergen Peptides’ (DFLAP) algorithm, which affords in silico determination of potential protein allergenicity of high sensitivity and excellent specificity. To strengthen bioinformatics risk assessment in allergology EVALLER provides a comprehensive outline of its judgment on a query protein's potential allergenicity. Each such textual output incorporates a scoring figure, a confidence numeral of the assignment and information on high- or low-scoring matches to identified allergen-related motifs, including their respective location in accordingly derived allergens. The interface, built on a modified Perl Open Source package, enables dynamic and color-coded graphic representation of key parts of the output. Moreover, pertinent details can be examined in great detail through zoomed views. The server can be accessed at http://bioinformatics.bmc.uu.se/evaller.html. PMID:17537818

AllerML: markup language for allergens.

PubMed

Ivanciuc, Ovidiu; Gendel, Steven M; Power, Trevor D; Schein, Catherine H; Braun, Werner

2011-06-01

Many concerns have been raised about the potential allergenicity of novel, recombinant proteins into food crops. Guidelines, proposed by WHO/FAO and EFSA, include the use of bioinformatics screening to assess the risk of potential allergenicity or cross-reactivities of all proteins introduced, for example, to improve nutritional value or promote crop resistance. However, there are no universally accepted standards that can be used to encode data on the biology of allergens to facilitate using data from multiple databases in this screening. Therefore, we developed AllerML a markup language for allergens to assist in the automated exchange of information between databases and in the integration of the bioinformatics tools that are used to investigate allergenicity and cross-reactivity. As proof of concept, AllerML was implemented using the Structural Database of Allergenic Proteins (SDAP; http://fermi.utmb.edu/SDAP/) database. General implementation of AllerML will promote automatic flow of validated data that will aid in allergy research and regulatory analysis. Copyright © 2011 Elsevier Inc. All rights reserved.

AllerML: Markup Language for Allergens

PubMed Central

Ivanciuc, Ovidiu; Gendel, Steven M.; Power, Trevor D.; Schein, Catherine H.; Braun, Werner

2011-01-01

Many concerns have been raised about the potential allergenicity of novel, recombinant proteins into food crops. Guidelines, proposed by WHO/FAO and EFSA, include the use of bioinformatics screening to assess the risk of potential allergenicity or cross-reactivities of all proteins introduced, for example, to improve nutritional value or promote crop resistance. However, there are no universally accepted standards that can be used to encode data on the biology of allergens to facilitate using data from multiple databases in this screening. Therefore, we developed AllerML a markup language for allergens to assist in the automated exchange of information between databases and in the integration of the bioinformatics tools that are used to investigate allergenicity and cross-reactivity. As proof of concept, AllerML was implemented using the Structural Database of Allergenic Proteins (SDAP; http://fermi.utmb.edu/SDAP/) database. General implementation of AllerML will promote automatic flow of validated data that will aid in allergy research and regulatory analysis. PMID:21420460

Comparison of international food allergen labeling regulations.

PubMed

Gendel, Steven M

2012-07-01

Food allergy is a significant public health issue worldwide. Regulatory risk management strategies for allergic consumers have focused on providing information about the presence of food allergens through label declarations. A number of countries and regulatory bodies have recognized the importance of providing this information by enacting laws, regulations or standards for food allergen labeling of "priority allergens". However, different governments and organizations have taken different approaches to identifying these "priority allergens" and to designing labeling declaration regulatory frameworks. The increasing volume of the international food trade suggests that there would be value in supporting sensitive consumers by harmonizing (to the extent possible) these regulatory frameworks. As a first step toward this goal, an inventory of allergen labeling regulations was assembled and analyzed to identify commonalities, differences, and future needs. Published by Elsevier Inc.

Molecular profiles: a new tool to substantiate serum banks for evaluation of potential allergenicity of GMO.

PubMed

Barber, D; Rodríguez, R; Salcedo, G

2008-10-01

Assessment of the allergenicity of GMOs involves performing a test with a panel of sera obtained from allergic donors. However, there is no clear indication of how to characterize the above-mentioned panel. The patient selection criteria should take into account the geographical location of patients, the intensity and nature of the environmental allergens in the area and the potential cross-reactivity among allergenic molecules. Sera for serum banks, obtained from patients with demonstrated food allergy, should be subjected to a further characterization by screening with a panel of relevant allergenic molecules. A representative panel of these sera should be used in the allergenicity assessment. Finally, the "in vitro" methodologies should have the adequate specificity and sensitivity, and the integrity of the molecules tested should be guaranteed.

Antigen-specific Treg cells in immunological tolerance: implications for allergic diseases

PubMed Central

Abdel-Gadir, Azza; Massoud, Amir H.; Chatila, Talal A.

2018-01-01

Allergic diseases are chronic inflammatory disorders in which there is failure to mount effective tolerogenic immune responses to inciting allergens. The alarming rise in the prevalence of allergic diseases in recent decades has spurred investigations to elucidate the mechanisms of breakdown in tolerance in these disorders and means of restoring it. Tolerance to allergens is critically dependent on the generation of allergen-specific regulatory T (Treg) cells, which mediate a state of sustained non-responsiveness to the offending allergen. In this review, we summarize recent advances in our understanding of mechanisms governing the generation and function of allergen-specific Treg cells and their subversion in allergic diseases. We will also outline approaches to harness allergen-specific Treg cell responses to restore tolerance in these disorders. PMID:29375821

Purification and characterization of allergens from Xanthium strumarium pollen.

PubMed

Jaggi, K S; Gangal, S V

1987-12-01

The allergenic components present in whole pollen extract of Xanthium strumarium were isolated by sequential ammonium sulphate precipitation, DEAE Sephadex A50 chromatography and gel filtration. The techniques of RAST inhibition and skin test were utilized to check the allergenicity of fractionated proteins revealing the presence of Xan Ib and Xan VIa as the important allergenic components. Xan Ib was found to be devoid of carbohydrate and had a molecular weight of 103,000 daltons. Xan VIa was a glycoprotein of molecular weight 17,000 daltons. The carbohydrate moiety of Xan VIa was found to be associated with allergenicity. The characteristic pattern of whole pollen extract on CIE and TLIEF showed 36 and 21 protein bands, respectively. The use of FPLC in isolation of partially purified allergens from Xanthium is discussed.

Public protection - reliable allergen risk management

NASA Astrophysics Data System (ADS)

Janković, V.; Popov Raljić, J.; Đorđević, V.

2017-09-01

Consumers with potentially fatal food allergies are dependent on correct product labelling to protect their health. The food industry is responsible for providing every detail consumers need to make informed decisions. Considering public health, food suppliers have to monitor the presence of allergens, prevent cross-contamination and label products accurately. Allergen labelling of food products, drinks and non pre-packed food and drink products is clearly defined with legal regulations. To achieve this, a complete understanding of each product’s allergenic ingredients is needed and cross-contamination of food with allergens must be avoided. Raw materials need to be checked, every ingredient must be verified and every single allergen has to be stipulated. A mislabeled product could be recalled at potential cost, financially damaging business and at the same time, negatively impacting brand and reputation.

Expression, purification, and characterization of almond (Prunus dulcis) allergen Pru du 4.

PubMed

Zhang, Yuzhu; Du, Wen-Xian; Fregevu, Cécile; Kothary, Mahendra H; Harden, Leslie; McHugh, Tara H

2014-12-31

Biochemical characterizations of food allergens are required for understanding the allergenicity of food allergens. Such studies require a relatively large amount of highly purified allergens. The level of Pru du 4 in almond is low, and its expression in a soluble form in Escherichia coli required an expression tag. An MBP tag was used to enhance its expression and solubility. Sumo was used for the first time as a peptidase recognition site. The expression tag was removed with a sumo protease, and the resulting wild-type Pru du 4 was purified chromatographically. The stability of the allergen was investigated with chemical denaturation. The Gibbs free energy of Pru du 4 folding-unfolding transition was determined to be 5.4 ± 0.7 kcal/mol.

[Molecular aspects of allergy to plant products. Part III. Panallergens and breeding of hypoallergenic cultivars].

PubMed

Bokszczanin, Kamila Ł; Przybyła, Andrzej A

2012-04-01

In addition to major allergens, also minor allergens, i.e. panallergens have been shown to be responsible for many IgE cross-reactions even between unrelated pollen and plant food allergen sources. It can be explained also by cross-allergenicity underlying the T cell response to conserved regions of panallergens. In this article, we focus on known panallergens which presently comprise a few protein families, including non-specific lipid transfer proteins (nsLTP) (PR-14), thaumatin like proteins (TLP) (PR-5), profilins, and polcalcins. Food allergy has an impact on the quality of life of an allergic patient. The way of developing novel plant cultivars with decreased allergenicity and possibility of down-regulating the expression of an allergen by genetic modification are discussed.

Assessment of Environmental Cockroach Allergen Exposure

PubMed Central

Chew, Ginger L.

2016-01-01

In the past, cockroach allergen exposure assessment mainly focused on settled dust in homes in low-income urban cities in the United States. That choice was not wrong; without measureable levels of cockroach allergen, it is difficult to show associations with any home characteristics much less with health outcomes (e.g., allergy, asthma). However, recent studies in other suburban areas, schools, and other countries have elucidated the importance of cockroach allergen in these environments too. In addition, characterizing the underlying factors that give rise to cockroach allergen exposure (or protect against it) can lead to more targeted public health interventions. This review discusses different approaches to sampling indoor environments, interprets recent asthma and allergy studies, compares cockroach allergen levels from past studies with those of recent studies, and describes strategies to decrease exposures. PMID:22825884

Concentrations of major grass group 5 allergens in pollen grains and atmospheric particles: implications for hay fever and allergic asthma sufferers sensitized to grass pollen allergens.

PubMed

Schäppi, G F; Taylor, P E; Pain, M C; Cameron, P A; Dent, A W; Staff, I A; Suphioglu, C

1999-05-01

Grass pollen allergens are the most important cause of hay fever and allergic asthma during summer in cool temperate climates. Pollen counts provide a guide to hay fever sufferers. However, grass pollen, because of its size, has a low probability of entering the lower airways to trigger asthma. Yet, grass pollen allergens are known to be associated with atmospheric respirable particles. We aimed (1) to determine the concentration of group 5 major allergens in (a) pollen grains of clinically important grass species and (b) atmospheric particles (respirable and nonrespirable) and (2) to compare the atmospheric allergen load with clinical data to assess different risk factors for asthma and hay fever. We have performed a continuous 24 h sampling of atmospheric particles greater and lower than 7.2 microm in diameter during the grass pollen season of 1996 and 1997 (17 October 1996-16 January 1997) by means of a high volume cascade impactor at a height of about 15 m above ground in Melbourne. Using Western analysis, we assessed the reactivity of major timothy grass allergen Phl p 5 specific monoclonal antibody (MoAb) against selected pollen extracts. A MoAb-based ELISA was then employed to quantify Phl p 5 and cross-reactive allergens in pollen extracts and atmospheric particles larger and smaller than 7.2 microm. Phl p 5-specific MoAb detected group 5 allergens in tested grass pollen extracts, indicating that the ELISA employed here determines total group 5 allergen concentrations. On average, 0.05 ng of group 5 allergens were detectable per grass pollen grain. Atmospheric group 5 allergen concentrations in particles > 7.2 microm were significantly correlated with grass pollen counts (rs = 0.842, P < 0. 001). On dry days, 37% of the total group 5 allergen load, whereas upon rainfall, 57% of the total load was detected in respirable particles. After rainfall, the number of starch granule equivalents increased up to 10-fold; starch granule equivalent is defined as a hypothetical potential number of airborne starch granules based on known pollen count data. This indicates that rainfall tended to wash out large particles and contributed to an increase in respirable particles containing group 5 allergens by bursting of pollen grains. Four day running means of group 5 allergens in respirable particles and of asthma attendances (delayed by 2 days) were shown to be significantly correlated (P < 0.001). Here we present, for the first time, an estimation of the total group 5 allergen content in respirable and nonrespirable particles in the atmosphere of Melbourne. These results highlight the different environmental risk factors for hay fever and allergic asthma in patients, as on days of rainfall following high grass pollen count, the risk for asthma sufferers is far greater than on days of high pollen count with no associated rainfall. Moreover, rainfall may also contribute to the release of allergens from fungal spores and, along with the release of free allergen molecules from pollen grains, may be able to interact with other particles such as pollutants (i.e. diesel exhaust carbon particles) to trigger allergic asthma.

Functional Genomics of Allergen Gene Families in Fruits

PubMed Central

Maghuly, Fatemeh; Marzban, Gorji; Laimer, Margit

2009-01-01

Fruit consumption is encouraged for health reasons; however, fruits may harbour a series of allergenic proteins that may cause discomfort or even represent serious threats to certain individuals. Thus, the identification and characterization of allergens in fruits requires novel approaches involving genomic and proteomic tools. Since avoidance of fruits also negatively affects the quality of patients’ lives, biotechnological interventions are ongoing to produce low allergenic fruits by down regulating specific genes. In this respect, the control of proteins associated with allergenicity could be achieved by fine tuning the spatial and temporal expression of the relevant genes. PMID:22253972

Allergic contact dermatitis to indium in jewellery: diagnosis made possible through the use of the Contact Allergen Bank Australia.

PubMed

Gamboni, Sarah E; Simmons, Ivan; Palmer, Amanda; Nixon, Rosemary L

2013-05-01

We report a case of a 39-year-old woman from Adelaide who developed allergic contact dermatitis to the rare allergen indium in her ring. The allergen was sourced for patch testing using the Contact Allergen Bank Australia (CABA), based at the Skin and Cancer Foundation in Melbourne, and posted to Adelaide. This case illustrates the usefulness of CABA in facilitating patch testing throughout Australia, especially when rare allergens are involved. © 2013 The Authors. Australasian Journal of Dermatology © 2013 The Australasian College of Dermatologists.

Practical environmental modifications for the inhalant allergy patient.

PubMed

Gage-White, L

1998-02-01

Environmental management of inhalant allergens is an important part of a comprehensive allergy management program and is the most controllable aspect by the patient. The safest and most effective way to eliminate an allergic reaction is to eliminate exposure to the antigen that provokes the response. The basic control principles for all inhalant allergens are to (1) remove the source of the allergen if possible, (2) remove accumulated allergen, and (3) prevent the return of the allergen. This article examines the published evidence for environmental control measures in terms of effectiveness, cost, and ease of implementation.

Role of p38 MAPK in the selective release of IL-8 induced by chemical allergen in naive THp-1 cells.

PubMed

Mitjans, Montserrat; Viviani, Barbara; Lucchi, Laura; Galli, Corrado L; Marinovich, Marina; Corsini, Emanuela

2008-03-01

At present, the assessment of the allergenic potential of chemicals is carried out using animal models. Over the last decade, several in vitro methods mainly using primary dendritic cells have been proposed to identify the potential of chemicals to induce skin sensitization to meet current animal welfare and public opinions. The major limitations of such tests are the donor-to-donor variability, the low levels in the source, and a possible shortage of human sources. The aim of the present investigation was to establish an in vitro test to identify chemical allergens using the human promyelocytic cell line THP-1 in order to avoid some of these difficulties. We investigated whether the chemokine interleukin-8 or CXCL8 (IL-8) production could provide a methodology for the detection of both respiratory and contact allergens. THP-1 cells were exposed to contact allergens (cinnamaldehyde, dinitrochlorobenzene, nickel sulfate, penicillin G, p-phenylenediamine, tetramethylthiuram disulfide), to respiratory allergens (ammonium hexachloroplatinate, diphenylmethane diisocyanate, trimellitic anhydride) and to irritants (salicylic acid, phenol, sodium lauryl sulphate). Following 48 h of incubation, the release of IL-8 was evaluated by sandwich ELISA. IL-8 production was significantly increased after stimulation with all allergens tested, with the exception of trimellitic anhydride, whereas irritants exposure failed to induce IL-8 release. The lack of IL-8 production by trimellitic anhydride can be explained by the rapid hydrolysis of this chemical in water to trimellitic acid, which is not an allergen. In contrast to IL-8 release, CD54 and CD86 expression did not provide a sensitive method failing to correctly identify approximately 30% of the tested compounds. Although CD86 appears to be a more sensitive marker than CD54 when discriminating allergens from irritants neither of these markers provided robust methodology. We also investigated if a common activation pathway in allergen-induced IL-8 production involving p38 mitogen-activated protein kinase could be identified. By Western blot analysis we could indeed demonstrate p38 activation by all chemical allergens tested and, using the selective p38 MAPK inhibitor SB203580, a significant modulation of allergen-induced IL-8 release could be achieved in all cases. Our data suggests that production of IL-8 by naïve THP-1 cells may represent a promising in vitro model for the screening of potential chemical allergens and activation of p38 MAPK represents a common pathway triggered by allergens.

8 Allergenic Composition of Polymerized Allergen Extracts of Betula verrucosa, Dermatophagoides Pteronyssinus and Phleum Pratense

PubMed Central

Fernandez-Caldas, Enrique; Cases, Barbara; Tudela, Jose Ignacio; Fernandez, Eva Abel; Casanovas, Miguel; Subiza, Jose Luis

2012-01-01

Background Allergoids have been successfully used in the treatment of respiratory allergic diseases. They are modified allergen extracts that allow the administration of high allergen doses, due to their reduced IgE binding capacity.They maintain allergen-specific T-cell recognition. Since they are native allergen extracts that have been polymerized with glutaraldehyde, identification of the allergenic molecules requires more complicated methods. The aim of the study was to determine the qualitative composition of different polymerized extracts and investigate the presence of defined allergenic molecules using Mass spectrometry. Methods Proteomic analysis was carried out at the Proteomics Facility of the Hospital Nacional de Parapléjicos (Toledo, Spain). After reduction and alkylation, proteins were digested with trypsin and the resulting peptides were cleaned using C18 SpinTips Sample Prep Kit; peptides were separated on an Ultimate nano-LC system using a Monolithic C18 column in combination with a precolumn for salt removal. Fractionation of the peptides was performed with a Probot microfraction collector and MS and MS/MS analysis of offline spotted peptide samples were performed using the Applied Biosystems 4800 plus MALDI TOF/TOF Analyzer mass spectrometer. ProteinPilot Software V 2.0.1 and the Paragon algorithm were used for the identification of the proteins. Each MS/MS spectrum was searched against the SwissProt 2010_10 database, Uniprot-Viridiplantae database and Uniprot_Betula database. Results Analysis of the peptides revealed the presence of native allergens in the polymerized extracts: Der p 1, Der p 2, Der p 3, Der p 8 and Der p 11 in D. pteronyssinus; Bet v 2, Bet v 6, Bet v 7 and several Bet v 1 isoforms in B. verrucosa and Phl p 1, Phl p 3, Phl p 5, Phl p 11 and Phl p 12 in P. pratense allergoids. In all cases, potential allergenic proteins were also identified, including ubiquitin, actin, Eenolase, fructose-bisphosphate aldolase, luminal-binding protein (Heat shock protein 70), calmodulin, among others. Conclusions The characterization of the allergenic composition of allergoids is possible using MS/MS analysis. The analysis confirms the presence of native allergens in the allergoids. Mayor allergens are preserved during polymerization.

Nanoparticle-allergen interactions mediate human allergic responses: protein corona characterization and cellular responses.

PubMed

Radauer-Preiml, Isabella; Andosch, Ancuela; Hawranek, Thomas; Luetz-Meindl, Ursula; Wiederstein, Markus; Horejs-Hoeck, Jutta; Himly, Martin; Boyles, Matthew; Duschl, Albert

2016-01-16

Engineered nanomaterials (ENMs) interact with different biomolecules as soon as they are in contact, resulting in the formation of a biomolecule 'corona'. Hence, the 'corona' defines the biological identity of the ENMs and could affect the response of the immune system to ENM exposure. With up to 40 % of the world population suffering from type I allergy, a possible modulation of allergen effects by binding to ENMs is highly relevant with respect to work place and consumer safety. Therefore, the aim of this present study was to gain an insight into the interactions of gold nanoparticles with different seasonally and perennially occurring outdoor and indoor allergens. Gold nanoparticles (AuNPs) were conjugated with the major allergens of birch pollen (Bet v 1), timothy grass pollen (Phl p 5) and house dust mite (Der p 1). The AuNP-allergen conjugates were characterized by means of TEM negative staining, dynamic light scattering (DLS), z-potential measurements and hyperspectral imaging. Furthermore, 3D models were constructed, based on the characterization data, to visualize the interaction between the allergens and the AuNPs surface. Differences in the activation of human basophil cells derived from birch/grass pollen- and house dust mite-allergic patients in response to free allergen and AuNP-allergen conjugates were determined using the basophil activation assay (BAT). Potential allergen corona replacement during BAT was controlled for using Western blotting. The protease activity of AuNP-Der p 1 conjugates compared to free Der p 1 was assessed, by an enzymatic activity assay and a cellular assay pertaining to lung type II alveolar epithelial cell tight junction integrity. The formation of a stable corona was found for all three allergens used. Our data suggest, that depending on the allergen, different effects are observed after binding to ENMs, including enhanced allergic responses against Der p 1 and also, for some patients, against Bet v 1. Moreover elevated protease activity of AuNP-Der p 1 conjugates compared to free Der p 1 was found. In summary, this study presents that conjugation of allergens to ENMs can modulate the human allergic response, and that protease activity can be increased. Graphical Abstract Cross-linking of IgE receptors and degranulation of human basophils due to epitope alignment of nanoparticle-coated allergens.

HEPA air filter (image)

MedlinePlus

... pet dander and other irritating allergens from the air. Along with other methods to reduce allergens, such ... controlling the amount of allergens circulating in the air. HEPA filters can be found in most air ...

Assessment of the allergenic potential of transgenic wheat (Triticum aestivum) with reduced levels of omega-5 gliadins, the major sensitizing allergen in wheat-dependent exercise-induced anaphylaxis

USDA-ARS?s Scientific Manuscript database

The omega-5 gliadins are the major sensitizing allergens in wheat-dependent exercise-induced anaphylaxis (WDEIA). In this study, two-dimensional immunoblot analysis was used to assess the allergenic potential of two transgenic wheat lines in which omega-5 gliadin genes were silenced by RNA interfe...

Comparison of Allergenicity at Gly m 4 and Gly m Bd 30K of Soybean after Genetic Modification.

PubMed

Tsai, Jaw-Ji; Chang, Ching-Yun; Liao, En-Chih

2017-02-15

Despite rapid growth of genetically modified (GM) crops, effective evaluations of genetic modification on allergenicity are still lacking. Gly m Bd 30K is cross-reactive with cow's milk protein casein, Gly m 4, and with birch pollen allergen Bet v 1. Here we compared the allergenicity between GM and non-GM soybeans with respect to the foci Gly m 4 and Gly m Bd 30K. Recombinant allergens of Gly m Bd 30K and Gly m 4 were generated and polyclonal antibodies raised to identify these two allergenic components in soybeans. GM soybean was first PCR-confirmed using 35S promoter. A total of 20 soybeans (half GM, half non-GM) obtained from a food market were used to assess their allergenicity based on IgE-binding and histamine release. The concentrations of Gly m Bd 30K and Gly m 4 in soybeans were then determined. Most soybean-allergic patients (9 of 10) showed IgE-positive reactions to the allergen of 30 kDa in molecular weight. That allergen turned out to be Glycine max Gly m Bd 30K based on LC-MS/MS analyses. Gly m Bd 30K is therefore the major allergen in the soybean. An increase in the transcription of both the Gly m 4 (stress-induced protein SAM22) and Gly m Bd 28K (soybean allergen precursor) was found after genetic modification. The protein concentrations of Gly m 4 and Gly m Bd 30K were not statistically significant different between non-GM and GM soybeans. There were also no statistical significances between them in the tests of IgE binding and histamine release. In conclusion, soybeans showed similar concentrations of Gly m Bd 30K and Gly m 4 regardless of genetic modification or absence thereof. The allergenicity of both Gly m Bd 30K and Gly m 4 was therefore not altered after genetic modification. Patients showing hypersensitivity to soybeans and who had pre-existing allergy to birch pollen and cow's milk casein might not further increase their allergic reactions following exposures to the GM soybeans.

Effects of autoclaving and high pressure on allergenicity of hazelnut proteins

PubMed Central

2012-01-01

Background Hazelnut is reported as a causative agent of allergic reactions. However it is also an edible nut with health benefits. The allergenic characteristics of hazelnut-samples after autoclaving (AC) and high-pressure (HHP) processing have been studied and are also presented here. Previous studies demonstrated that AC treatments were responsible for structural transformation of protein structure motifs. Thus, structural analyses of allergen proteins from hazelnut were carried out to observe what is occurring in relation to the specific-IgE recognition of the related allergenic proteins. The aims of this work are to evaluate the effect of AC and HHP processing on hazelnut in vitro allergenicity using human-sera and to analyse the complexity of hazelnut allergen-protein structures. Methods Hazelnut-samples were subjected to AC and HHP processing. The specific IgE- reactivity was studied in 15 allergic clinic-patients via western blotting analyses. A series of homology-based-bioinformatics 3D-models (Cora 1, Cora 8, Cora 9 and Cora 11) were generated for the antigens included in the study to analyse the co mplexity of their protein structure. This study is supported by the Declaration of Helsinki and subsequent ethical guidelines. Results A severe reduction in vitro in allergenicity to hazelnut after AC processing was observed in the allergic clinic-patients studied. The specific-IgE binding of some of the described immunoreactive hazelnut protein-bands: Cora 1 ~18KDa, Cora 8 ~9KDa, Cora 9 ~35-40KDa and Cora 11 ~47-48 KDa decreases. Furthermore a relevant glycosylation was assigned and visualized via structural analysis of proteins (3D-modelling) for the first time in the protein-allergen Cora 11 showing a new role which could open a new door for allergenicity-unravellings. Conclusion Hazelnut allergenicity-studies in vivo via Prick-Prick and other means using AC processing are crucial to verify the data we observed via in vitro analyses. Glycosylation studies provided us with clues to elucidate, in the near future, mechanisms of the structures that contribute to hazelnut allergenicity, which thus, in turn, help alleviate food allergens. PMID:22616776

Increased Th1 and Th2 allergen-induced cytokine responses in children with atopic disease.

PubMed

Smart, J M; Kemp, A S

2002-05-01

Polyclonal cytokine responses following stimulation of T cells with mitogens or superantigens provides information on cytokine production from a wide range of T cells. Alternatively allergen-induced T cell responses can provide information on cytokine production by allergen-reactive T cells. While there is evidence of increased Th2 and reduced Th1 cytokine production following T cell stimulation with non-specific mitogens and superantigens, the evidence that Th1 cytokine production to allergens is decreased in line with a postulated imbalance in Th1/Th2 responses is unclear, with studies finding decreased, no difference or increased IFN-gamma responses to allergens in atopic subjects. To examine childhood polyclonal and allergen-induced cytokine responses in parallel to evaluate cytokine imbalances in childhood atopic disease. PBMC cytokine responses were examined in response to a polyclonal stimulus, staphylococcal superantigen (SEB), in parallel with two inhalant allergens, house dust mite (HDM) and rye grass pollen (RYE), and an ingested allergen, ovalbumin (OVA), in (a) 35 healthy children (non-atopic) and (b) 36 children with atopic disease (asthma, eczema and/or rhinitis) (atopic). Atopic children had significantly reduced IFN-gamma and increased IL-4 and IL-5 but not IL13 production to SEB superantigen stimulation when compared with non-atopic children. HDM and RYE allergens stimulated significantly increased IFN-gamma, IL-5 and IL-13, while OVA stimulated significantly increased IFN-gamma production in atopic children. We show that a polyclonal stimulus induces a reduced Th1 (IFN-gamma) and increased Th2 (IL-4 and IL-5) cytokine pattern. In contrast, the allergen-induced cytokine responses in atopic children were associated with both increased Th1 (INF-gamma) and Th2 (IL-5 and IL-13) cytokine production. The increased Th1 response to allergen is likely to reflect prior sensitization and indicates that increases in both Th1 and Th2 cytokine production to allergens exists concomitantly with a decreased Th1 response to a polyclonal stimulus in atopic children.

Grass pollen allergens globally: the contribution of subtropical grasses to burden of allergic respiratory diseases.

PubMed

Davies, J M

2014-06-01

Grass pollens of the temperate (Pooideae) subfamily and subtropical subfamilies of grasses are major aeroallergen sources worldwide. The subtropical Chloridoideae (e.g. Cynodon dactylon; Bermuda grass) and Panicoideae (e.g. Paspalum notatum; Bahia grass) species are abundant in parts of Africa, India, Asia, Australia and the Americas, where a large and increasing proportion of the world's population abide. These grasses are phylogenetically and ecologically distinct from temperate grasses. With the advent of global warming, it is conceivable that the geographic distribution of subtropical grasses and the contribution of their pollen to the burden of allergic rhinitis and asthma will increase. This review aims to provide a comprehensive synthesis of the current global knowledge of (i) regional variation in allergic sensitivity to subtropical grass pollens, (ii) molecular allergenic components of subtropical grass pollens and (iii) allergic responses to subtropical grass pollen allergens in relevant populations. Patients from subtropical regions of the world show higher allergic sensitivity to grass pollens of Chloridoideae and Panicoideae grasses, than to temperate grass pollens. The group 1 allergens are amongst the allergen components of subtropical grass pollens, but the group 5 allergens, by which temperate grass pollen extracts are standardized for allergen content, appear to be absent from both subfamilies of subtropical grasses. Whilst there are shared allergenic components and antigenic determinants, there are additional clinically relevant subfamily-specific differences, at T- and B-cell levels, between pollen allergens of subtropical and temperate grasses. Differential immune recognition of subtropical grass pollens is likely to impact upon the efficacy of allergen immunotherapy of patients who are primarily sensitized to subtropical grass pollens. The literature reviewed herein highlights the clinical need to standardize allergen preparations for both types of subtropical grass pollens to achieve optimal diagnosis and treatment of patients with allergic respiratory disease in subtropical regions of the world. © 2014 John Wiley & Sons Ltd.

Dog allergen (Can f 1) and cat allergen (Fel d 1) in US homes: Results from the National Survey of Lead and Allergens in Housing

PubMed Central

Arbes, Samuel J.; Cohn, Richard D.; Yin, Ming; Muilenberg, Michael L.; Friedman, Warren; Zeldin, Darryl C.

2017-01-01

Background Exposures to dog and cat allergens are believed to play important roles in the etiology of asthma; however, the levels of these allergens have never been assessed in a representative sample of US homes. Objective The objective of this study was to estimate and characterize exposures to Can f 1 (dog allergen) and Fel d 1 (cat allergen) in US homes. Methods Data were obtained from the National Survey of Lead and Allergens in Housing, a nationally representative survey of 831 US homes. Vacuumed-collected dust samples from the bed, bedroom floor, living room floor, and living room sofa were analyzed for concentrations of Can f 1 and Fel d 1 (micrograms of allergen per gram of dust). Results Although a dog or cat had lived in only 49.1% of homes in the previous 6 months, Can f 1 and Fel d 1 were detected in 100% and 99.9% of homes, respectively. Averaged over the sampled sites, geometric mean concentrations (µg/g) were 4.69 for Can f 1 and 4.73 for Fel d 1. Among homes with an indoor dog and cat, respectively, geometric mean concentrations were 69 for Can f 1 and 200 for Fel d 1. Among homes without the indoor pet, geometric mean concentrations were above 1.0. The independent predictors of elevated concentrations in homes without pets were all demographic variables that were also linked to a higher prevalence of pet ownership. Conclusions Can f 1 and Fel d 1 are universally present in US homes. Levels that have been associated with an increased risk of allergic sensitization were found even in homes without pets. Because of the transportability of these allergens on clothing, elevated levels in homes without pets, particularly among demographic groups in which pet ownership is more prevalent, implicate the community as an important source of these pet allergens. PMID:19055206