WorldWideScience

Sample records for chemically modified allergens

  1. Modified Allergens for Immunotherapy.

    Science.gov (United States)

    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.

  2. [Chemical modification of allergen leading to changes in its epitopic activity].

    Science.gov (United States)

    Babakhin, A A; Gushchin, I S; Andreev, S M; Petrukhina, A I; Viler, A V; Stokinger, B; Nolte, G; Dubuske, L M; Khaitov, R M; Petrpv, R V

    1999-01-01

    Modification of a model allergen ovalbumin (OA) with succinylation led to a decrease of its allergenicity measured by passive cutaneous anaphylaxis reaction, RAST inhibition assay and basophil histamine release. Modified OA stimulated OA-specific T-cell hybrid 3DO-548 to produce IL-2 at the same level as in case of non-modified OA. Modified OA did not induce anti-OA IgE, but did induce anti-OA IgG antibodies. This approach to chemical modification of allergen-selective blockade of B-cell epitopes while not affecting T-cell epitopes suggests new opportunities in creation of safe and effective allergovaccines.

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

    Science.gov (United States)

    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.

  4. Endogenous allergens and compositional analysis in the allergenicity assessment of genetically modified plants.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  6. [Assessment of allergenicity of genetically modified food crops].

    Science.gov (United States)

    Schauzu, M; Pöting, A; Rubin, D; Lampen, A

    2012-03-01

    The placing on the European Union's market of genetically modified crops requires authorization by the European Commission which is based on the proof that the derived foods are as safe as their conventional counterparts. The assessment of potential allergenicity is part of the necessary investigations recommended in the updated Guidance Document of the Scientific Panel on Genetically Modified Organisms (GMO) of the European Food Safety Authority (EFSA), which is based on internationally agreed recommendations. All genetically modified crops which so far have been authorized in the European Union were evaluated by the EFSA GMO Panel which considered it unlikely that their overall allergenicity has been altered.

  7. Chemical modification of Art v 1, a major mugwort pollen allergen, by cis-aconitylation and citraconylation

    Directory of Open Access Journals (Sweden)

    DRAGANA STANIĆ

    2009-04-01

    Full Text Available Art v 1 is the major allergen of mugwort (Artemisia vulgaris pollen, a significant cause of hay fever all over Europe. Specific immunotherapy is the only treatment modality for allergic disease. Application of modified allergens makes the treatment safer and more efficient. In this work, two out of three (citraconic anhydride, cis-aconitic anhydride, 2,3-dimethylmaleic anhydride tested anhydrides were proven to be suitable for chemical modifications of allergens. Art v 1 was modified by cis-aconitylation and citraconylation in order to obtain derivatives of Art v 1 that may be suitable for further immunological testing. Acylation of Art v 1 gave derivatives (caaArt v 1 and citArt v 1 with about 80 % modified amino groups. The derivatives were in the monomeric form and had dramatically reduced pI values. Both derivatives were relatively stable at neutral pH values, while the acyl groups undergo hydrolysis under acidic conditions. Modification of allergens by cis-aconitylation and citraconylation could be a new tool for obtaining allergoids.

  8. A review of animal models used to evaluate potential allergenicity of genetically modified organisms (GMOs)

    DEFF Research Database (Denmark)

    Marsteller, Nathan; Bøgh, Katrine Lindholm; Goodman, Richard E.

    2017-01-01

    Food safety regulators request prediction of allergenicity for newly expressed proteins in genetically modified (GM) crops and in novel foods. Some have suggested using animal models to assess potential allergenicity. A variety of animal models have been used in research to evaluate sensitisation...... of genetically modified organisms (GMOs).......Food safety regulators request prediction of allergenicity for newly expressed proteins in genetically modified (GM) crops and in novel foods. Some have suggested using animal models to assess potential allergenicity. A variety of animal models have been used in research to evaluate sensitisation...

  9. Responses of human birch pollen allergen-reactive T cells to chemically modified allergens (allergoids).

    Science.gov (United States)

    Dormann, D; Ebner, C; Jarman, E R; Montermann, E; Kraft, D; Reske-Kunz, A B

    1998-11-01

    Allergoids are widely used in specific immunotherapy for the treatment of IgE-mediated allergic diseases. The aim of this study was to analyse whether a modification of birch pollen allergens with formaldehyde affects the availability of T-cell epitopes. Efficient modification of the allergens was verified by determining IgE and IgG binding activity using ELISA inhibition tests. T-cell responses to birch pollen allergoids were analysed in polyclonal systems, using peripheral blood mononuclear cells (PBMC) of five birch pollen-allergic individuals, as well as birch pollen extract-reactive T-cell lines (TCL), established from the peripheral blood of 14 birch pollen-allergic donors. To determine whether the modification of natural (n)Bet v 1 with formaldehyde or maleic anhydride results in epitope-specific changes in T-cell reactivities, 22 Bet v 1-specific T-cell clones (TCC), established from nine additional birch pollen-allergic individuals, were tested for their reactivity with these products. The majority of PBMC and TCL showed a reduced response to the birch pollen extract allergoid. Bet v 1-specific TCC could be divided into allergoid-reactive and -non-reactive TCC. No simple correlation between possible modification sites of formaldehyde in the respective T-cell epitopes and the stimulatory potential of the allergoid was observed. Mechanisms of suppression or of anergy induction were excluded as an explanation for the non-reactivity of representative TCC. All TCC could be stimulated by maleylated and unmodified nBet v 1 to a similar extent. These results demonstrate differences in the availability of T-cell epitopes between allergoids and unmodified allergens, which are most likely due to structural changes within the allergen molecule.

  10. Quality requirements for allergen extracts and allergoids for allergen immunotherapy.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  12. Reduced in vitro T-cell responses induced by glutaraldehyde-modified allergen extracts are caused mainly by retarded internalization of dendritic cells.

    Science.gov (United States)

    Heydenreich, Bärbel; Bellinghausen, Iris; Lorenz, Steffen; Henmar, Helene; Strand, Dennis; Würtzen, Peter A; Saloga, Joachim

    2012-06-01

    Although allergen-specific immunotherapy is a clinically effective therapy for IgE-mediated allergic diseases, the risk of IgE-mediated adverse effects still exists. For this reason, chemically modified allergoids have been introduced, which may destroy IgE-binding sites while T-cell activation should be retained. The aim of the study was to analyse the differences between intact allergens and differently modified/aggregated allergoids concerning their internalization as well as T-cell and basophil activation. For this purpose human monocyte-derived immature dendritic cells (DC) were incubated with Phleum pratense or Betula verrucosa pollen extract or with the corresponding allergoids, modified with formaldehyde or glutaraldehyde. After an additional maturation process, the antigen-loaded mature DC were co-cultured with autologous CD4(+) T cells. Allergenicity was tested by leukotriene release from basophils. In addition, the uptake of intact allergens and allergoids by immature DC was analysed. The proliferation of, as well as the interleukin-4 (IL-4), IL-10, IL-13 and interferon-γ production by, CD4(+) T cells which had been stimulated with glutaraldehyde allergoid-treated DC was reduced compared with CD4(+) T cells stimulated with intact allergen-treated or formaldehyde allergoid-treated DC. In line with this, glutaraldehyde-modified allergoids were more aggregated and were internalized more slowly. Furthermore, only the allergoids modified with glutaraldehyde induced a decreased leukotriene release by activated basophils. These findings suggest that IgE-reactive epitopes were destroyed more efficiently by modification with glutaraldehyde than with formaldehyde under the conditions chosen for these investigations. Glutaraldehyde-modified allergoids also displayed lower T-cell stimulatory capacity, which is mainly the result of greater modification/aggregation and diminished uptake by DC. © 2012 The Authors. Immunology © 2012 Blackwell Publishing Ltd.

  13. Characterization of modified allergen extracts by in vitro beta-hexosaminidase release from rat basophils.

    Science.gov (United States)

    Gehlhar, Kirsten; Peters, Marcus; Brockmann, Kirsten; van Schijndel, Hans; Bufe, Albrecht

    2005-04-01

    To date, there is no well-established test available that can be used to measure functional properties of modified allergens (allergoids). Due to the cross-linking process, the IgE-binding capacity of the allergens, normally necessary for their characterization, is lost. The aim of this study was to test whether the rat basophilic leukaemia (RBL) cell assay (beta-hexosaminidase release by rat basophils upon allergen stimulation) can be adopted to characterize allergoids and to evaluate the assay for testing allergoids and native allergens as well. Mice were immunized with native and modified Phleumpratense extracts in the presence of alum. Their sera were used to sensitize RBL-2H3 cells and measure basophil stimulation induced by different allergen extracts in the presence or absence of various additives. Sera containing specific IgE against both extract formulations were obtained. Native as well as modified extracts induced dose-dependent beta-hexosaminidase release from RBL cells. Both extracts were used to evaluate the characteristics of the assay, which showed high precision. Storage conditions were chosen to enhance extract degradation, which could be read directly from the altered stimulatory capacity of the extracts. Additives turned out to have diverse effects on the assay, whereas phenol had no measurable effect, alum had an inhibitory effect and glycerol elevated basophil activation. For the first time, a reliable, precise in vitro assay is available that is able to directly measure the properties of modified allergen extracts after their production process. The test is well evaluated and its advantages and limitations are discussed in this report. Copyright (c) 2005 S. Karger AG, Basel

  14. Potential allergenicity research of Cry1C protein from genetically modified rice.

    Science.gov (United States)

    Cao, Sishuo; He, Xiaoyun; Xu, Wentao; Luo, Yunbo; Ran, Wenjun; Liang, Lixing; Dai, Yunqing; Huang, Kunlun

    2012-07-01

    With the development of genetically modified crops, there has been a growing interest in available approaches to assess the potential allergenicity of novel gene products. We were not sure whether Cry1C could induce allergy. We examined the protein with three other proteins to determine the potential allergenicity of Cry1C protein from genetically modified rice. Female Brown Norway (BN) rats received 0.1 mg peanut agglutinin (PNA), 1mg potato acid phosphatase (PAP), 1mg ovalbumin (OVA) or 5 mg purified Cry1C protein dissolved in 1 mL water by daily gavage for 42 days to test potential allergenicity. Ten days after the last gavage, rats were orally challenged with antigens, and physiologic and immunologic responses were studied. In contrast to sensitization with PNA, PAP and OVA Cry1C protein did not induce antigen-specific IgG2a in BN rats. Cytokine expression, serum IgE and histamine levels and the number of eosinophils and mast cells in the blood of Cry1C group rats were comparable to the control group rats, which were treated with water alone. As Cry1C did not show any allergenicity, we make the following conclusion that the protein could be safety used in rice or other plants. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Chemical allergens stimulate human epidermal keratinocytes to produce lymphangiogenic vascular endothelial growth factor

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Ok-Nam [College of Pharmacy, Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan 426-791 (Korea, Republic of); Ahn, Seyeon; Jin, Sun Hee; Hong, Soo Hyun; Lee, Jinyoung [College of Pharmacy, Natural Products Research Institute, Seoul National University, Seoul 151-742 (Korea, Republic of); Kim, Eun-Sun [College of Pharmacy, Institute of Pharmaceutical Science and Technology, Hanyang University, Ansan 426-791 (Korea, Republic of); Jeong, Tae Cheon [College of Pharmacy, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Chun, Young-Jin [College of Pharmacy, Chung-Ang University, Seoul 156-756 (Korea, Republic of); Lee, Ai-Young, E-mail: leeay@duih.org [Department of Dermatology, Dongguk University Ilsan Hospital, Goyang 410-773 (Korea, Republic of); Noh, Minsoo, E-mail: minsoo@alum.mit.edu [College of Pharmacy, Natural Products Research Institute, Seoul National University, Seoul 151-742 (Korea, Republic of)

    2015-03-01

    Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture. VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD. - Highlights: • Pro-inflammatory cytokines induced VEGF production in normal human

  16. Chemical allergens stimulate human epidermal keratinocytes to produce lymphangiogenic vascular endothelial growth factor

    International Nuclear Information System (INIS)

    Bae, Ok-Nam; Ahn, Seyeon; Jin, Sun Hee; Hong, Soo Hyun; Lee, Jinyoung; Kim, Eun-Sun; Jeong, Tae Cheon; Chun, Young-Jin; Lee, Ai-Young; Noh, Minsoo

    2015-01-01

    Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture. VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD. - Highlights: • Pro-inflammatory cytokines induced VEGF production in normal human

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

    Science.gov (United States)

    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

  18. New routes of allergen immunotherapy.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    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 to 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.

  1. Food allergen digestibility: The influence on allergenicity

    DEFF Research Database (Denmark)

    Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

    potential exist. Resistance to digestion is therefore a test parameter included in the safety assessment of the allergenic potential of novel proteins in genetically modified foods. In recent years, the association between resistance to digestion and allergenic potential has been challenged. When reviewing......Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. What makes a dietary protein a food allergen has not yet been established, though several characteristics have been proposed to be shared by the food allergens. One of the features believed...... existing data from digestibility studies on known food allergens, it becomes evident that food allergens do not necessarily resist digestion. However, the choice of assay conditions, the method used for detection of residual intact protein as well as fragments hereof greatly influences the outcome. Studies...

  2. Relationship of CD86 surface marker expression and cytotoxicity on dendritic cells exposed to chemical allergen

    International Nuclear Information System (INIS)

    Hulette, Ben C.; Ryan, Cindy A.; Gildea, Lucy A.; Gerberick, G. Frank

    2005-01-01

    Human peripheral blood-derived dendritic cells (DC) respond to a variety of chemical allergens by up-regulating expression of the co-stimulatory molecule CD86. It has been postulated that this measure might provide the basis for an in vitro alternative approach for the identification of skin sensitizing chemicals. We recently reported that DC, exposed in culture to the highest non-cytotoxic concentrations of various chemical allergens, displayed marginal up-regulation of membrane CD86 expression; the interpretation being that such changes were insufficiently sensitive for the purposes of hazard identification. For the work presented here, immature DC were derived from human monocytes and treated with the chemical allergens 2,4-dinitrobenzenesulfonic acid (DNBS), nickel sulfate (NiSO 4 ), p-phenylenediamine (PPD), Bandrowski's base (BB), hydroquinone (HQ) and propyl gallate (PG) for 48 h at concentrations which induced both no to slight to moderate cytotoxicity. For comparison, DC were treated with the irritants sodium dodecyl sulfate (SDS), benzoic acid (BA), and benzalkonium chloride (BZC) at concentrations resulting in comparable levels of cytotoxicity. CD86 expression, as measured by flow cytometry, was consistently up-regulated (ranging from 162 to 386% control) on DC treated with concentrations of chemical allergens that induced approximately 10-15% cytotoxicity. The irritants BA and BZC did not induce up-regulation of CD86 expression when tested at concentrations that induced similar levels of cytotoxicity. SDS, however, up-regulated CD86 expression to 125-138% of control in 2/4 preparations when tested at concentrations which induced similar toxicity. Our results confirm that chemical allergens up-regulate CD86 expression on blood-derived DC and illustrate further that up-regulation of CD86 surface marker expression is more robust when DC are treated with concentrations of chemical allergen that induce slight to moderate cytotoxicity

  3. Chemical allergens stimulate human epidermal keratinocytes to produce lymphangiogenic vascular endothelial growth factor.

    Science.gov (United States)

    Bae, Ok-Nam; Ahn, Seyeon; Jin, Sun Hee; Hong, Soo Hyun; Lee, Jinyoung; Kim, Eun-Sun; Jeong, Tae Cheon; Chun, Young-Jin; Lee, Ai-Young; Noh, Minsoo

    2015-03-01

    Allergic contact dermatitis (ACD) is a cell-mediated immune response that involves skin sensitization in response to contact with various allergens. Angiogenesis and lymphangiogenesis both play roles in the allergic sensitization process. Epidermal keratinocytes can produce vascular endothelial growth factor (VEGF) in response to UV irradiation and during wound healing. However, the effect of haptenic chemical allergens on the VEGF production of human keratinocytes, which is the primary contact site of toxic allergens, has not been thoroughly researched. We systematically investigated whether immune-regulatory cytokines and chemical allergens would lead to the production of VEGF in normal human keratinocytes (NHKs) in culture. VEGF production significantly increased when NHKs were treated with IFNγ, IL-1α, IL-4, IL-6, IL-17A, IL-22 or TNFα. Among the human sensitizers listed in the OECD Test Guideline (TG) 429, we found that CMI/MI, DNCB, 4-phenylenediamine, cobalt chloride, 2-mercaptobenzothiazole, citral, HCA, cinnamic alcohol, imidazolidinyl urea and nickel chloride all significantly upregulated VEGF production in NHKs. In addition, common human haptenic allergens such as avobenzone, formaldehyde and urushiol, also induced the keratinocyte-derived VEGF production. VEGF upregulation by pro-inflammatory stimuli, IFNγ, DNCB or formaldehyde is preceded by the production of IL-8, an acute inflammatory phase cytokine. Lymphangiogenic VEGF-C gene transcription was significantly increased when NHKs were treated with formaldehyde, DNCB or urushiol, while transcription of VEGF-A and VEGF-B did not change. Therefore, the chemical allergen-induced VEGF upregulation is mainly due to the increase in lymphangiogenic VEGF-C transcription in NHKs. These results suggest that keratinocyte-derived VEGF may regulate the lymphangiogenic process during the skin sensitization process of ACD. Copyright © 2015 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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

  5. ASSESSMENT OF ALLERGENIC POTENTIAL OF GENETICALLY MODIFIED FOODS: AN AGENDA FOR FUTURE RESEARCH

    Science.gov (United States)

    AbstractSpeakers and participants in the Workshop Assessment of the Allergenic Potential of Genetically Modified Foods met in breakout groups to discuss a number of issues including needs for future research. There was agreement that research should move forward quickly in t...

  6. Chemical and Biological Properties of Food Allergens

    NARCIS (Netherlands)

    Jedrychowski, L.; Wichers, H.J.

    2009-01-01

    This book provides epidemiological data on food allergens and information on the incidence of food allergies. It discusses the link between hypersensitivity and immune system health and covers methods used for assays on allergenic components, animal models for allergen analysis, and clinical methods

  7. Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids - differences in vivo and in vitro.

    Science.gov (United States)

    Heydenreich, B; Bellinghausen, I; Lund, L; Henmar, H; Lund, G; Adler Würtzen, P; Saloga, J

    2014-06-01

    Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native Phleum pratense or Betula verrucosa allergen extract or formaldehyde- or glutaraldehyde-modified allergoids, adsorbed or unadsorbed to alum. After maturation, DC were co-cultivated with autologous CD4(+) T cells. Allergenicity was tested by leukotriene and histamine release of human basophils. Finally, in-vivo immunogenicity was analysed by IgG production of immunized mice. T cell proliferation as well as interleukin (IL)-4, IL-13, IL-10 and interferon (IFN)-γ production were strongly decreased using glutaraldehyde-modified allergoids, but did not differ between alum-adsorbed allergens or allergoids and the corresponding unadsorbed preparations. Glutaraldehyde modification also led to a decreased leukotriene and histamine release compared to native allergens, being further decreased by adsorption to alum. In vivo, immunogenicity was reduced for allergoids which could be partly restored by adsorption to alum. Our results suggest that adsorption of native allergens or modified allergoids to alum had no consistent adjuvant effect but led to a reduced allergenicity in vitro, while we observed an adjuvant effect regarding IgG production in vivo. © 2014 British Society for Immunology.

  8. 484 Allergen Standardisation in Allergens and Allergoids—Challenges and Considerations

    Science.gov (United States)

    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.

  9. The influence of digestibility on the allergenicity of food allergens

    DEFF Research Database (Denmark)

    Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

    2012-01-01

    potential exist. Resistance to digestion is therefore a test parameter included in the safety assessment of the allergenic potential of novel proteins in genetically modified foods. In recent years, the association between resistance to digestion and allergenic potential has been challenged. When reviewing......Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. What makes a dietary protein a food allergen has not yet been established, though several characteristics have been proposed to be shared by the food allergens. One of the features believed...... existing data from digestibility studies on known food allergens, it becomes evident that food allergens do not necessarily resist digestion. However, the choice of assay conditions, the method used for detection of residual intact protein as well as fragments hereof greatly influences the outcome. Studies...

  10. Role of p38 MAPK in the selective release of IL-8 induced by chemical allergen in naive THp-1 cells.

    Science.gov (United States)

    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

  11. Adjuvant effects of aluminium hydroxide-adsorbed allergens and allergoids – differences in vivo and in vitro

    Science.gov (United States)

    Heydenreich, B; Bellinghausen, I; Lund, L; Henmar, H; Lund, G; Adler Würtzen, P; Saloga, J

    2014-01-01

    Allergen-specific immunotherapy (SIT) is a clinically effective therapy for immunoglobulin (Ig)E-mediated allergic diseases. To reduce the risk of IgE-mediated side effects, chemically modified allergoids have been introduced. Furthermore, adsorbance of allergens to aluminium hydroxide (alum) is widely used to enhance the immune response. The mechanisms behind the adjuvant effect of alum are still not completely understood. In the present study we analysed the effects of alum-adsorbed allergens and allergoids on their immunogenicity in vitro and in vivo and their ability to activate basophils of allergic donors. Human monocyte derived dendritic cells (DC) were incubated with native Phleum pratense or Betula verrucosa allergen extract or formaldehyde-or glutaraldehyde-modified allergoids, adsorbed or unadsorbed to alum. After maturation, DC were co-cultivated with autologous CD4+ T cells. Allergenicity was tested by leukotriene and histamine release of human basophils. Finally, in-vivo immunogenicity was analysed by IgG production of immunized mice. T cell proliferation as well as interleukin (IL)-4, IL-13, IL-10 and interferon (IFN)-γ production were strongly decreased using glutaraldehyde-modified allergoids, but did not differ between alum-adsorbed allergens or allergoids and the corresponding unadsorbed preparations. Glutaraldehyde modification also led to a decreased leukotriene and histamine release compared to native allergens, being further decreased by adsorption to alum. In vivo, immunogenicity was reduced for allergoids which could be partly restored by adsorption to alum. Our results suggest that adsorption of native allergens or modified allergoids to alum had no consistent adjuvant effect but led to a reduced allergenicity in vitro, while we observed an adjuvant effect regarding IgG production in vivo. PMID:24528247

  12. 8 Allergenic Composition of Polymerized Allergen Extracts of Betula verrucosa, Dermatophagoides Pteronyssinus and Phleum Pratense

    OpenAIRE

    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 qual...

  13. Measurement of endogenous allergens in genetically modified soybeans--short communication.

    Science.gov (United States)

    Ladics, Gregory S; Budziszewski, Gregory J; Herman, Rod A; Herouet-Guicheney, Corinne; Joshi, Saurabh; Lipscomb, Elizabeth A; McClain, Scott; Ward, Jason M

    2014-10-01

    The measurement of endogenous allergens is required by the European Commission (EC) as part of the compositional analysis for GM products from host plants that are common causes of food allergy, such as soybean (EC Implementing Regulation No. 503/2013). In each case, the EC Implementing Regulation indicates that analysis be conducted on identified allergens as specified in the Organization of Economic Cooperation and Development (OECD) consensus documents on compositional considerations for new plant varieties. This communication discusses the methods available to measure endogenous allergens as well as the endogenous soybean allergens that should be analyzed. It is suggested herein that in conjunction with the 2012 OECD consensus document on soybean, any list of soybean allergens should be based on clinically relevant data among publicly available allergen databases and peer-reviewed scientific publications, and the ability to measure the identified allergen. Based on a detailed analysis of the scientific literature, the following key points are recommended: (1) the acceptance of serum-free, quantitative analytical method data as an alternative to traditional IgE reactivity qualitative or semi-quantitative data for evaluation of endogenous soybean allergen content; (2) eight of the 15 potential allergens listed in the OECD soybean consensus document (Gly m 3, Gly m 4, Gly m Bd28K, Gly m Bd30K, Gly m 5, Gly m 6, Gly m 8, and Kunitz trypsin inhibitor) have both appropriate supporting clinical data and sufficient sequence information to be evaluated in comparative endogenous soybean allergen studies; and (3) the remaining seven proteins (Gly m 1, Gly m 2, unknown 50kDa protein, unknown 39kDa protein, P-22-25, lipoxygenase and lectin) lack sufficient data for clear classification as confirmed allergens and/or available sequence information and should not be currently included in the measurement of endogenous soybean allergens in the compositional analysis for the EU

  14. In vitro evaluation of digestive and endolysosomal enzymes to cleave CML-modified Ara h 1 peptides

    Science.gov (United States)

    The sensory, biological, chemical, and immunological characteristics of foods can be modified non-enzymatically during processing. Notably, these modifications may modulate the allergenic potency of food allergens, such as the Ara h 1 peanut allergen. Carboxymethyl-lysine (CML) modification is a p...

  15. KEY ISSUES FOR THE ASSESSMENT OF THE ALLERGENIC POTENTIAL OF GENETICALLY MODIFIED FOODS: BREAKOUT GROUP REPORTS

    Science.gov (United States)

    AbstractOn the final afternoon of the Workshop, Assessment of the Allergenic Potential of Genetically Modified Foods, speakers and participants met in breakout groups to discuss specific questions in the areas of 1) Use of Human Clinical Data; 2) Animal Models to Assess Food ...

  16. 13-year overview of serious adverse drug reactions following subcutaneous specific immunotherapy with a chemically modified allergen preparation.

    Science.gov (United States)

    Distler, Andreas; Pappelendam, Debbie

    The Paul-Ehrlich-Institut (PEI) published an analysis of reports of adverse drug reactions (ADRs) in 2001 with test and therapy allergens from the period from 1991 to 2000. Possible risk factors were evaluated for the ADR reports classified as "serious". During the analyzed period, modified semi-depot preparations (allergoids) induced between 0.01 % and 0.0005 % serious systemic reactions, i. e. one serious ADR occurred in 10,000 to 200,000 injections. No information was provided regarding the respective incidences in relation to the individual companies or preparations. Within the scope of a 13-year analysis (2001-2013), the serious ADRs were analysed at HAL for the allergoid preparations PURETHAL® Pollen and Mites. As in the analysis of PEI, the frequency of serious ADRs was based on the estimated number of administered injections. A total of 46 cases with serious ADRs were received. In 26 % of the cases, a serious ADR occurred during initial treatment after the first injection. In 82.6 % of the cases, the serious ADR occurred within the 30-minute observation period in the practice. Adrenaline was administered as emergency treatment in seven cases. Hospitalisations were initiated by the treating physician or by patients themselves in 45 cases. The duration of the hospital stay varied from a few hours up to three days for further monitoring. Serious ADRs occurred in 11 cases with mites and in 35 cases with pollen. If it is assumed that there are six injections in each vial, this yields an incidence of 0.00061 % (1 : 164,000). The frequency with mites (0.00093 %) was slightly higher than with pollen (0.00055 %). The allergoid preparations (pollen and mite allergens) showed a very low risk of serious ADRs, which was close to the lower level of incidence of 0.0005 % for allergoid preparations published by the PEI.

  17. Prediction of allergenicity of gene-modified foods by serum-based testing

    DEFF Research Database (Denmark)

    Poulsen, Lars K.

    2002-01-01

    On the basis of applying the IFBC/ILSI decision tree in a number of cases, a refinement of the scheme is suggested. Large differences in allergenic potential may be obtained by altering the route of administration of an allergen. Because an inhalation allergen can induce symptoms at different...

  18. Allergens of mites

    Directory of Open Access Journals (Sweden)

    Emilia Siwak

    2014-04-01

    Full Text Available Mite allergens belong to the group of inhalant allergens and represent antigenic substances which are particutlarly important in the pathogenesis of respiratory system diseases and skin diseases. The most common diseases associated with chronic exposure to these aeroallergens include: allergic rhinitis, bronchial asthma and atopic dermatitis. Mite allergens are simple proteins or glycoproteins with different molecular structures and various biochemical functions. The sensitizing capacity of these proteins is connected from their physicochemical properties. Individual allergens perform, among others, the functions of structural proteins, act as enzymes, transport lipids, bind metal ions, and are capable of glycosylation. In addition, mite allergenic proteases degrade proteins of the skin epithelium-resulting in a weakening of its natural protective barrier-and induce the immune response. The proteases also induce the release of pro-inflammatory cytokines: interleukin-4 (IL-4, interleukin 6 (IL-6, interleukin 8 (IL-8, eotaxin, and granulocyte-macrophage colony-stimulating factor-GM-CSF. The article presents the tertiary structure of major and mid-range mite allergens and their classification. Based on literature reports concerning the chemical structure of allergenic proteins, it was emphasized that the structural differences between homologous proteins with allergenic pozoproperties relate to the distribution of amino acid residues on the surface of the molecule. IgE binding affinity and the similarities and differences in the amino acid sequence of the allergens were also the basis for determining cross-reactivity of allergenic proteins. The paper shows an example of this phenomenon, describing the existence of common allergens for various mite species.

  19. Predicting allergenicity of proteins using Physical–Chemical Property (PCP) motifs

    Science.gov (United States)

    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...

  20. In silico Allergenicity Study of Insect resistant genetically Modified Rice (Oryza sativa L. for assessment of biosafety

    Directory of Open Access Journals (Sweden)

    S.K. Das

    2017-12-01

    Full Text Available India is one of the world's largest producers of rice (Oryza sativa, accounting for 20% of all world rice production. However, lepidopteran pests severely impact the harvest of rice, which leads to environmental pollution and increase production cost. Alternatively, genetic engineering methods may be used to prevent rice pests and increase production of rice in a safe and environmentally friendly manner. Bacillus thuringiensis (Bt genes have been widely used to generate genetically modified (GM crops because the expressed cry1Ab protein confers resistance to lepidopteron pests. The proteins expressed by these genes may lead to food safety problems. Thus, safety evaluations are necessary prior to commercialization. Bioinformatics analysis for allergenicity assessment of cry1Ab protein is performed using different allergen databases viz. FARRP SDAP, Allergome, and Algpred to identify any potential sequence matches to allergen proteins that might indicate allergenic cross-reactivity with the query sequence. A full FASTA search was performed to identify highly similar proteins. However; the full length search cannot identify discontinuous or conformational epitopes that depend upon the tertiary structure of the protein.So every possible contiguous 80-amino acid sequence of each query protein was searched for determining the similarity. The proteins sequence can be searched using FASTA/BLAST for broad homology to known allergens to identify any short sequence that might represent an allergenic epitope. The domains in the Cry protein sequences were searched using Interproscan for potential similarity at the domain level. The results showed neither significant alignment nor similarity of cry1Ab protein at full sequence, domain, and epitope level with any of the known allergen proteins in the full sequence matching. Matching the 80 amino acid and matching of 8 amino acids showed no similarity to determine the epitope potential. From literature survey

  1. Ultrarush schedule of subcutaneous immunotherapy with modified allergen extracts is safe in paediatric age.

    Science.gov (United States)

    Morais-Almeida, Mário; Arêde, Cristina; Sampaio, Graça; Borrego, Luis Miguel

    2016-01-01

    Traditional subcutaneous immunotherapy up dosing with allergenic extracts has been shown to be associated with frequent adverse reactions. In recent studies it has been demonstrated that using modified extracts, namely allergoids, it is a safe and effective procedure particularly on accelerated schedules. However data assessing its safety in paediatric age is scarce. To evaluate the safety profile in paediatric population of using modified allergen extracts, in an ultrarush schedule, to reach the maintenance dose in the first day. We included children undergoing treatment with subcutaneous immunotherapy during a five-year period, using modified aeroallergen extracts, depigmented, polymerized with glutaraldehyde and adsorbed on aluminium hydroxide using an ultrarush induction phase. The type of adverse reactions during the ultrarush protocol was recorded. We studied 100 paediatric patients (57 males) with a mean age of 11.6 years (5 to 18 years; standard deviation, 3.3), all with moderate to severe persistent rhinitis, with or without allergic conjunctivitis, asthma and atopic eczema, sensitized to mites and/or pollens. All reached the maintenance dose of 0.5 mL in the first day, except 1 child. During the ultrarush protocol the total number of injections was 199. There were 21 local adverse reactions in 11 patients, 11 immediate and 10 delayed; from those, had clinical relevance 1 immediate and 4 delayed. Systemic reactions were recorded in 2 cases, both immediate and mild. The ultrarush protocol, without premedication, was a safe alternative to be used in paediatric age during the induction phase of subcutaneous immunotherapy using allergoid depigmented extracts.

  2. Allergen immunotherapy in allergic rhinitis: current use and future trends.

    Science.gov (United States)

    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.

  3. Modifications of allergenicity linked to food technologies.

    Science.gov (United States)

    Moneret-Vautrin, D A

    1998-01-01

    The prevalence of food allergies (FA) has increased over the past fifteen years. The reasons suggested are changes in dietary behaviour and the evolution of food technologies. New cases of FA have been described with chayote, rambutan, arguta, pumpkin seeds, custard apple, and with mycoproteins from Fusarium.... Additives using food proteins are at high risk: caseinates, lysozyme, cochineal red, papaïn, alpha-amylase, lactase etc. Heating can reduce allergenicity or create neo-allergens, as well as storage, inducing the synthesis of allergenic stress or PR proteins. Aeroallergens (miles, moulds) contaminate foods and can induce allergic reactions. Involuntary contamination by peanut proteins on production lines is a problem which is not yet solved. Genetically modified plants are at risk of allergenicity, requiring methodological steps of investigations: the comparison of the amino-acid sequence of the transferred protein with the sequence of known allergens, the evaluation of thermo degradability and of the denaturation by pepsin and trypsin are required, as well as the study with sera from patients allergic to the plant producing the gene. The combination of enzymatic hydrolysis, heating, or the development of genetically modified plants may offer new alternatives towards hypoallergenic foods (57 references).

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

    Science.gov (United States)

    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.

  5. Reactivity measurement in estimation of benzoquinone and benzoquinone derivatives’ allergenicity

    International Nuclear Information System (INIS)

    Mbiya, Wilbes; Chipinda, Itai; Simoyi, Reuben H.; Siegel, Paul D.

    2016-01-01

    Benzoquinone (BQ) and benzoquinone derivatives (BQD) are used in the production of dyes and cosmetics. While BQ, an extreme skin sensitizer, is an electrophile known to covalently modify proteins via Michael Addition (MA) reaction whilst halogen substituted BQD undergo nucleophilic vinylic substitution (SNV) mechanism onto amine and thiol moieties on proteins, the allergenic effects of adding substituents on BQ have not been reported. The effects of inserting substituents on the BQ ring has not been studied in animal assays. However, mandated reduction/elimination of animals used in cosmetics testing in Europe has led to an increased need for alternatives for the prediction of skin sensitization potential. Electron withdrawing and electron donating substituents on BQ were assessed for effects on BQ reactivity toward nitrobenzene thiol (NBT). The NBT binding studies demonstrated that addition of EWG to BQ as exemplified by the chlorine substituted BQDs increased reactivity while addition of EDG as in the methyl substituted BQDs reduced reactivity. BQ and BQD skin allerginicity was evaluated in the murine local lymph node assay (LLNA). BQD with electron withdrawing groups had the highest chemical potency followed by unsubstituted BQ and the least potent were the BQD with electron donating groups. The BQD results demonstrate the impact of inductive effects on both BQ reactivity and allergenicity, and suggest the potential utility of chemical reactivity data for electrophilic allergen identification and potency ranking.

  6. Reactivity measurement in estimation of benzoquinone and benzoquinone derivatives’ allergenicity

    Science.gov (United States)

    Mbiya, Wilbes; Chipinda, Itai; Simoyi, Reuben H.; Siegel, Paul D.

    2015-01-01

    Benzoquinone (BQ) and benzoquinone derivatives (BQD) are used in the production of dyes and cosmetics. While BQ, an extreme skin sensitizer, is an electrophile known to covalently modify proteins via Michael Addition (MA) reaction whilst halogen substituted BQD undergo nucleophilic vinylic substitution (SNV) mechanism onto amine and thiol moieties on proteins, the allergenic effects of adding substituents on BQ have not been reported. The effects of inserting substituents on the BQ ring has not been studied in animal assays. However, mandated reduction/elimination of animals used in cosmetics testing in Europe has led to an increased need for alternatives for the prediction of skin sensitization potential. Electron withdrawing and electron donating substituents on BQ were assessed for effects on BQ reactivity toward nitrobenzene thiol (NBT). The NBT binding studies demonstrated that addition of EWG to BQ as exemplified by the chlorine substituted BQDs increased reactivity while addition of EDG as in the methyl substituted BQDs reduced reactivity. BQ and BQD skin allerginicity was evaluated in the murine local lymph node assay (LLNA). BQD with electron withdrawing groups had the highest chemical potency followed by unsubstituted BQ and the least potent were the BQD with electron donating groups. The BQD results demonstrate the impact of inductive effects on both BQ reactivity and allergenicity, and suggest the potential utility of chemical reactivity data for electrophilic allergen identification and potency ranking. PMID:26612505

  7. Effects of daily food processing on allergenicity.

    Science.gov (United States)

    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.

  8. Allergen-specific immunotherapy

    Directory of Open Access Journals (Sweden)

    Moote William

    2011-11-01

    Full Text Available Abstract Allergen-specific immunotherapy is a potentially disease-modifying therapy that is effective for the treatment of allergic rhinitis/conjunctivitis, allergic asthma and stinging insect hypersensitivity. However, despite its proven efficacy in these conditions, it is frequently underutilized in Canada. The decision to proceed with allergen-specific immunotherapy should be made on a case-by-case basis, taking into account individual patient factors such as the degree to which symptoms can be reduced by avoidance measures and pharmacological therapy, the amount and type of medication required to control symptoms, the adverse effects of pharmacological treatment, and patient preferences. Since this form of therapy carries the risk of anaphylactic reactions, it should only be prescribed by physicians who are adequately trained in the treatment of allergy. Furthermore, injections must be given under medical supervision in clinics that are equipped to manage anaphylaxis. In this article, the authors review the indications and contraindications, patient selection criteria, and the administration, safety and efficacy of allergen-specific immunotherapy.

  9. Sensitising capacity of peptides from food allergens

    DEFF Research Database (Denmark)

    Bøgh, Katrine Lindholm

    potential exist. Resistance to digestion is for this reason a test parameter included in the safety assessment of the allergenic potential of novel proteins in genetically modified foods. The association between resistance to digestion and allergenic potential has though been challenged in recent years...... and structures may contribute. In conclusion, the experimental data presented in this PhD thesis contribute to the understanding of induction of allergy by investigating the sensitising potential of peptides derived from a food allergen. It add knowledge to our understanding of the mechanisms underlying...

  10. Immunological, chemical and clinical aspects of exposure to mixtures of contact allergens

    DEFF Research Database (Denmark)

    Bonefeld, Charlotte M.; Geisler, Carsten; Gimenéz-Arnau, Elena

    2017-01-01

    relevant. In this article, we provide a general introduction to immune responses to contact allergens, and discuss the literature concerning immune responses to mixtures of allergens. According to the existing evidence, increased responses are induced following sensitization with combinations of allergens...

  11. Risk management of allergenic food ingredients in hospitality

    Directory of Open Access Journals (Sweden)

    Popov-Raljić Jovanka

    2017-01-01

    Full Text Available Food allergens have appeared in the last two decades as a concealed form of threat which significantly endangers public health, and their labelling on food products, drinks, and non pre-packed gastro-products is clearly defined with legal regulations. In practice, the chemical risk management is faced with several unexpected problems. Some of them are declarations or statements about allergenic ingredients, where a nutritional allergen that the food contains is labelled with an unusual name, or similar products from different manufacturers where one is safe and the other contains allergens. A hospitality facility which deals with production and distribution of unpackaged foods should, in addition to a developed HACCP concept and standardized recipes for food preparation, prepare a detailed, precise, and clearly defined plan for management of chemical risks.

  12. Ethosome formulations of known contact allergens can increase their sensitizing capacity

    DEFF Research Database (Denmark)

    Madsen, Jacob Torp; Vogel, Stefan; Karlberg, Ann-Therese

    2010-01-01

    a modified local lymph node assay (LLNA). The results were compared with those for the same allergens in similar concentrations and vehicles without ethosomes. Both allergens encapsulated in 200-300 nm ethosomes showed increased sensitizing potency in the murine assay compared with the allergens in solution...... without ethosomes. Empty ethosomes were non-sensitizing according to LLNA. The clinical implications are so far uncertain, but increased allergenicity from ethosome-encapsulated topical product ingredients cannot be excluded....

  13. A protocol for a systematic review to identify allergenic tree nuts and the molecules responsible for their allergenic properties.

    Science.gov (United States)

    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.

  14. Effects of Maillard reaction on allergenicity of buckwheat allergen Fag t 3 during thermal processing.

    Science.gov (United States)

    Yang, Zhen-Huang; Li, Chen; Li, Yu-Ying; Wang, Zhuan-Hua

    2013-04-01

    Fag t 3 is a major allergenic protein in tartary buckwheat. The Maillard reaction commonly occurs in food processing, but few studies have been conducted on the influence of thermal processing on the allergenic potential of buckwheat allergen. The aim of the present study was to investigate the effects of autologous plant polysaccharides on the immunoreactivity of buckwheat Fag t 3 (11S globulin) following the Maillard reaction. Fag t 3 and crude polysaccharides were prepared from tartary buckwheat (Fagopyrum tataricum) flour. After heating, the polysaccharides were covalently linked to Fag t 3 via a Maillard reaction, and the IgE/IgG-binding properties of Fag t 3 decreased dramatically, with significant changes also being observed in the electrophoretic mobility, secondary structure and solubility of the glycated Fag t 3. The great influence of glycation on IgE/IgG binding to Fag t 3 was correlated with a significant change in the structure and epitopes of the allergenic protein. These data indicated that conjugation of polysaccharides to Fag t 3 markedly reduced the allergen's immunoreactivity. Glycation that occurs via the Maillard reaction during the processing of buckwheat food may be an efficient method to reduce Fag t 3 allergenicity. © 2012 Society of Chemical Industry.

  15. Allergenicity assessment of genetically modified cucumber mosaic virus (CMV) resistant tomato (Solanum lycopersicon).

    Science.gov (United States)

    Lin, Chih-Hui; Sheu, Fuu; Lin, Hsin-Tang; Pan, Tzu-Ming

    2010-02-24

    Cucumber mosaic virus (CMV) has been identified as the causal agent of several disease epidemics in most countries of the world. Insect-mediated virus diseases, such as those caused by CMV, caused remarkable loss of tomato (Solanum lycopersicon) production in Taiwan. With expression of the CMV coat protein gene (Cmvcp) in a local popular tomato cultivar L4783, transgenic tomato line R8 has showed consistent CMV resistance through T(0) to T(8). In this report, the allergenicity of the CMV coat protein (CMV cp) expressed in transgenic tomato R8 was assessed by investigation of the expression of the transgene source of protein, sequence similarity with known allergens, and resistance to pepsin hydrolysis. There is no known account for either the CMV or its coat protein being an allergen. The result of a bioinformatic search also showed no significant homology between CMV cp and any known allergen. The pepsin-susceptible property of recombinant CMV cp was revealed by a simulated gastric fluid (SGF) assay. Following the most recent FAO/WHO decision tree, all results have indicated that CMV cp was a protein with low possibility to be an allergen and the transgenic tomato R8 should be considered as safe as its host.

  16. Use of murine models to detect the allergenicity of genetically modified Lactococcus lactis NZ9000/pNZPNK.

    Science.gov (United States)

    Chiang, Shen-Shih; Liu, Chin-Feng; Ku, Ting-Wei; Mau, Jeng-Leun; Lin, Hsin-Tang; Pan, Tzu-Ming

    2011-04-27

    By introducing aprN into Lactococcus lactis NZ9000, the genetically modified L. lactis NZ9000/pNZPNK successfully expressed the nattokinase. The safety assessment of this novel strain was based on allergenicity of pepsin digestion stability and murine model serologic identity. Subjecting to the GM strain and host to pepsin digestion, the soluble fractions and cell debris were fast degraded completely. Feeding with ovalbumin resulted in significantly higher production of IgG1 and IgE as compared to that of L. lactis NZ9000/pNZPNK or L. lactis NZ9000. Further, the serum IgG2a level increased dose-dependently at week 2 and induced immune reaction toward Th1 pathway. Secretion of cytokines IL-4 and IL-10 fed with lactococci was significantly lower than that of the OVA group. L. lactis NZ9000/pNZPNK did not increase the proliferation of type 2 helper T cells in spleen or induce allergenicity in BALB/c mice. On the basis of the results, the new GM lactic acid bacterium is regarded as safe to use.

  17. 8 Allergenic Composition of Polymerized Allergen Extracts of Betula verrucosa, Dermatophagoides Pteronyssinus and Phleum Pratense

    Science.gov (United States)

    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

  18. EAACI Guidelines on Allergen Immunotherapy

    DEFF Research Database (Denmark)

    Halken, Susanne; Larenas-Linnemann, Desiree; Roberts, Graham

    2017-01-01

    Allergic diseases are common and frequently coexist. Allergen immunotherapy (AIT) is a disease-modifying treatment for IgE-mediated allergic disease with effects beyond cessation of AIT that may include important preventive effects. The European Academy of Allergy and Clinical Immunology (EAACI) ...... of allergic co-morbidities in those with other allergic conditions. Evidence for the preventive potential of AIT as disease modifying treatment exists but there is an urgent need for more high-quality clinical trials....

  19. Recombinant allergy vaccines based on allergen-derived B cell epitopes.

    Science.gov (United States)

    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.

  20. Digestion of atopic allergens with trypsin α-chymotrypsin and pancreatic kallikrein, and influence of the allergens upon the proteolytic and esterolytic activity of these enzymes

    NARCIS (Netherlands)

    Berrens, L.

    1968-01-01

    The action of bovine trypsin, α-chymotrypsin and pancreatic kallikrein upon a number of atopic allergens has been studied by pH-stat measurements during short-term incubation. Most atopic allergens proved chemically resistant towards these enzymes. Graphs of enzyme susceptibility vs. the ratio of

  1. EFSA Panel on Genetically Modified Organisms (GMO); Draft Scientific Opinion on the assessment of allergenicity of GM plants and microorganisms and derived food and feed

    DEFF Research Database (Denmark)

    Sørensen, Ilona Kryspin

    The weight-of-evidence, case-by-case approach is considered the most appropriate way of assessing the allergenicity of genetically modified (GM) food and feed. This scientific opinion discusses various aspects to increase the strength and accuracy of this approach, including the latest developments...

  2. Specific immunotherapy modifies allergen-specific CD4+ T cell responses in an epitope-dependent manner

    Science.gov (United States)

    Wambre, Erik; DeLong, Jonathan H.; James, Eddie A.; Torres-Chinn, Nadia; Pfützner, Wolfgang; Möbs, Christian; Durham, Stephen R.; Till, Stephen J.; Robinson, David; Kwok, William W.

    2014-01-01

    Background Understanding the mechanisms by which the immune system induces and controls allergic inflammation at the T cell epitope level is critical for the design of new allergy vaccine strategies. Objective To characterize allergen-specific T cell responses linked with allergy or peripheral tolerance and to determine how CD4+ T cell responses to individual allergen-derived epitopes change over allergen-specific immunotherapy (ASIT). Methods Timothy grass pollen (TGP) allergy was used as a model for studying grass pollen allergies. The breadth, magnitude, epitope hierarchy and phenotype of the DR04:01-restricted TGP-specific T cell responses in ten grass pollen allergic, five non-atopic and six allergy vaccine-treated individuals was determined using an ex vivo pMHCII-tetramer approach. Results CD4+ T cells in allergic individuals are directed to a broad range of TGP epitopes characterized by defined immunodominance hierarchy patterns and with distinct functional profiles that depend on the epitope recognized. Epitopes that are restricted specifically to either TH2 or TH1/TR1 responses were identified. ASIT was associated with preferential deletion of allergen-specific TH2 cells and without significant change in frequency of TH1/TR1 cells. Conclusions Preferential allergen-specific TH2-cells deletion after repeated high doses antigen stimulation can be another independent mechanism to restore tolerance to allergen during immunotherapy. PMID:24373351

  3. Lack of detectable allergenicity in genetically modified maize containing "Cry" proteins as compared to native maize based on in silico & in vitro analysis.

    Directory of Open Access Journals (Sweden)

    Chandni Mathur

    Full Text Available Genetically modified, (GM crops with potential allergens must be evaluated for safety and endogenous IgE binding pattern compared to native variety, prior to market release.To compare endogenous IgE binding proteins of three GM maize seeds containing Cry 1Ab,1Ac,1C transgenic proteins with non GM maize.An integrated approach of in silico & in vitro methods was employed. Cry proteins were tested for presence of allergen sequence by FASTA in allergen databases. Biochemical assays for maize extracts were performed. Specific IgE (sIgE and Immunoblot using food sensitized patients sera (n = 39 to non GM and GM maize antigens was performed.In silico approaches, confirmed for non sequence similarity of stated transgenic proteins in allergen databases. An insignificant (p> 0.05 variation in protein content between GM and non GM maize was observed. Simulated Gastric Fluid (SGF revealed reduced number of stable protein fractions in GM then non GM maize which might be due to shift of constituent protein expression. Specific IgE values from patients showed insignificant difference in non GM and GM maize extracts. Five maize sensitized cases, recognized same 7 protein fractions of 88-28 kD as IgE bindng in both GM and non-GM maize, signifying absence of variation. Four of the reported IgE binding proteins were also found to be stable by SGF.Cry proteins did not indicate any significant similarity of >35% in allergen databases. Immunoassays also did not identify appreciable differences in endogenous IgE binding in GM and non GM maize.

  4. Suggested improvements for the allergenicity assessment of genetically modified plants used in foods.

    Science.gov (United States)

    Goodman, Richard E; Tetteh, Afua O

    2011-08-01

    Genetically modified (GM) plants are increasingly used for food production and industrial applications. As the global population has surpassed 7 billion and per capita consumption rises, food production is challenged by loss of arable land, changing weather patterns, and evolving plant pests and disease. Previous gains in quantity and quality relied on natural or artificial breeding, random mutagenesis, increased pesticide and fertilizer use, and improved farming techniques, all without a formal safety evaluation. However, the direct introduction of novel genes raised questions regarding safety that are being addressed by an evaluation process that considers potential increases in the allergenicity, toxicity, and nutrient availability of foods derived from the GM plants. Opinions vary regarding the adequacy of the assessment, but there is no documented proof of an adverse effect resulting from foods produced from GM plants. This review and opinion discusses current practices and new regulatory demands related to food safety.

  5. Mechanical properties of chemically modified portuguese pinewood

    OpenAIRE

    Lopes, Duarte B; Mai, Carsten; Militz, Holger

    2014-01-01

    To turn wood into a construction material with enhanced properties, many methods of chemical modification have been developed in the last few decades. In this work, mechanical properties of pine wood were chemically modified, compared and evaluated. Maritime pine wood (Pinus pinaster) was modified with four chemical processes: 1,3-dimethylol-4,5- dihydroxyethyleneurea, N-methylol melamine formaldehyde, tetra-alkoxysilane and wax. The following mechanical properties were assessed experiment...

  6. Nonadverse effects on allergenicity of isopentenyltransferase-transformed broccoli.

    Science.gov (United States)

    Liao, E C; Chen, J T; Chao, M L; Yu, S C; Chang, C Y; Chu, W S; Tsai, J J

    2013-01-01

    Genetically modified organisms (GMOs) provide modern agriculture with improvements in efficiency and the benefits of enhanced food production; however, the potential impact of GMOs on human health has not yet been clarified. To investigate the allergenicity of isopentenyltransferase (ipt)-transformed broccoli compared with non-GM broccoli. Sera from allergic individuals were used to identify the allergenicity of GM and non-GM broccoli. Immunoglobulin (Ig) binding of different lines of GM and non-GM broccoli was identified using immunoblotting, enzyme-linked immunosorbent assay, and the histamin release assay. Positive reactions to broccoli (Brassica Oleracea) were observed in 7.02% of individuals. Specific IgE to broccoli and total IgE fro allergic individuals were well correlated. The different tests performed showed no significant differences in the allergenicity of conventionally raised and GM broccoli, indicating the absence of unexpected effects on allergenicity in ipt-transformed plants. Using Western blot analysis we detected heterogeneous IgE-reactive allergenic components in broccoli-allergic sera, but no significant differences between GM an non-GM broccoli were observed in serum from the same patients. Our study demonstrates that there are no differences between GM (ipt-transformed) broccoli and non-GM broccoli, as determined by specific IgE in sera from broccoli-allergic patients. This indicates that there were no unexpected effects on allergenicity in this GM broccoli.

  7. [Use of THP-1 for allergens identification method validation].

    Science.gov (United States)

    Zhao, Xuezheng; Jia, Qiang; Zhang, Jun; Li, Xue; Zhang, Yanshu; Dai, Yufei

    2014-05-01

    Look for an in vitro test method to evaluate sensitization using THP-1 cells by the changes of the expression of cytokines to provide more reliable markers of the identification of sensitization. The monocyte-like THP-1 cells were induced and differentiated into THP-1-macrophages with PMA (0.1 microg/ml). The changes of expression of cytokines at different time points after the cells being treated with five known allergens, 2,4-dinitrochlorobenzene (DNCB), nickel sulfate (NiSO4), phenylene diamine (PPDA) potassium dichromate (K2Cr2O7) and toluene diisocyanate (TDI) and two non-allergens sodium dodecyl sulfate (SDS) and isopropanol (IPA) at various concentrations were evaluated. The IL-6 and TNF-alpha production was measured by ELISA. The secretion of IL-1beta and IL-8 was analyzed by Cytometric Bead Array (CBA). The section of the IL-6, TNF-alpha, IL-1beta and IL-8 were the highest when THP-1 cells were exposed to NiSO4, DNCB and K2Cr2O7 for 6h, PPDA and TDI for 12h. The production of IL-6 were approximately 40, 25, 20, 50 and 50 times for five kinds chemical allergens NiSO4, DNCB, K2Cr2O7, PPDA and TDI respectively at the optimum time points and the optimal concentration compared to the control group. The expression of TNF-alpha were 20, 12, 20, 8 and 5 times more than the control group respectively. IL-1beta secretion were 30, 60, 25, 30 and 45 times respectively compared to the control group. The production of IL-8 were approximately 15, 12, 15, 12 and 7 times respectively compared to the control group. Both non-allergens SDS and IPA significantly induced IL-6 secretion in a dose-dependent manner however SDS cause a higher production levels, approximately 20 times of the control. Therefore IL-6 may not be a reliable marker for identification of allergens. TNF-alpha, IL-1beta and IL-8 expressions did not change significantly after exposed to the two non-allergens. The test method using THP-1 cells by detecting the productions of cytokines (TNF-alpha, IL-1beta and

  8. The role of contact allergens in chronic idiopathic urticaria.

    Science.gov (United States)

    Hession, Meghan T; Scheinman, Pamela L

    2012-01-01

    The objective of this study was to determine whether contact allergens play a role in chronic idiopathic urticaria (CIU). We conducted a longitudinal prospective study of 23 patients with CIU. Patients were patch tested to a modified North American Contact Dermatitis Group standard, fragrance, and cosmetic series; other series were tested as warranted by relevant history and physical examination. Readings were performed at 48 and 72 hours. Patients were counseled to avoid proven contact allergens and were followed up 2 to 9 months after testing. Twenty-one of 23 patients were female. The mean age was 46 years. The mean duration of urticaria was 32 months. Of the 23 patients, 8 (35%) experienced improvement of their symptoms with allergen avoidance. Four (17%) experienced a complete remission, and 4 (17%) experienced partial improvement. Two of the complete responders challenged themselves to proven contact allergens and developed urticaria, which resolved upon allergen avoidance. The most common allergens were potassium dichromate (n = 9), nickel sulfate (n = 7), Myroxylon pereirae (n = 6), cobalt chloride, neomycin, p-phenylenediamine (n = 5); fragrance mix I, fragrance mix II (n = 4); cinnamic aldehyde (n = 3); and formaldehyde (n = 2). Patch testing may be helpful in the evaluation of CIU patients for whom previous workup has failed to reveal an etiology.

  9. Aspects of food processing and its effect on allergen structure.

    Science.gov (United States)

    Paschke, Angelika

    2009-08-01

    The article summarizes current physical and chemical methods in food processing as storage, preparation, separation, isolation or purification and thermal application on the one hand as well as enzymatic treatment on the other and their impact on the properties of food proteins. Novel methods of food processing like high pressure, electric field application or irradiation and their impact on food allergens are presented. The EU project REDALL (Reduced Allergenicity of Processed Foods, Containing Animal Allergens: QLK1-CT-2002-02687) showed that by a combination of enzyme and heat treatment the allergic potential of hen's egg decreased about 100 fold. Clinical reactions do not appear anymore. An AiF-FV 12024 N project worked with fruits like mango, lychee and apple. Processed mango and lychee had no change in allergenic potential during heating while e. g. canning. Apple almost lost its allergenic potential after pasteurization in juice production.

  10. Lack of Detectable Allergenicity in Genetically Modified Maize Containing “Cry” Proteins as Compared to Native Maize Based on In Silico & In Vitro Analysis

    Science.gov (United States)

    Mathur, Chandni; Kathuria, Pooran C.; Dahiya, Pushpa; Singh, Anand B.

    2015-01-01

    Background Genetically modified, (GM) crops with potential allergens must be evaluated for safety and endogenous IgE binding pattern compared to native variety, prior to market release. Objective To compare endogenous IgE binding proteins of three GM maize seeds containing Cry 1Ab,1Ac,1C transgenic proteins with non GM maize. Methods An integrated approach of in silico & in vitro methods was employed. Cry proteins were tested for presence of allergen sequence by FASTA in allergen databases. Biochemical assays for maize extracts were performed. Specific IgE (sIgE) and Immunoblot using food sensitized patients sera (n = 39) to non GM and GM maize antigens was performed. Results In silico approaches, confirmed for non sequence similarity of stated transgenic proteins in allergen databases. An insignificant (p> 0.05) variation in protein content between GM and non GM maize was observed. Simulated Gastric Fluid (SGF) revealed reduced number of stable protein fractions in GM then non GM maize which might be due to shift of constituent protein expression. Specific IgE values from patients showed insignificant difference in non GM and GM maize extracts. Five maize sensitized cases, recognized same 7 protein fractions of 88-28 kD as IgE bindng in both GM and non-GM maize, signifying absence of variation. Four of the reported IgE binding proteins were also found to be stable by SGF. Conclusion Cry proteins did not indicate any significant similarity of >35% in allergen databases. Immunoassays also did not identify appreciable differences in endogenous IgE binding in GM and non GM maize. PMID:25706412

  11. Epoxy modified bitumen : Chemical hardening and its interpretation

    NARCIS (Netherlands)

    Apostolidis, P.; Pipintakos, G.; van de Ven, M.F.C.; Liu, X.; Erkens, Sandra; Scarpas, Athanasios

    2018-01-01

    Epoxy modified bitumen (EMB) is a promising technology for long lasting paving materials ensuring higher resistance to rutting, oxygen- and moisture-induced damage. In this paper, an analysis of the chemical reactions that take place during the chemical hardening process (curing) of epoxy modified

  12. Allergenic fragments of ryegrass (Lolium perenne) pollen allergen Lol p IV.

    Science.gov (United States)

    Jaggi, K S; Ekramoddoullah, A K; Kisil, F T

    1989-01-01

    To facilitate studies on establishing the nature of structure/function relationships of allergens, ryegrass pollen allergen, Lol p IV, was cleaved into smaller fragments by cyanogen bromide (CNBr) and the resulting peptides were further digested with trypsin. The resulting peptides were then fractionated by high performance liquid chromatography (HPLC) on a C-18 reverse phase column. The allergenic activity of the HPLC fractions was evaluated in terms of their ability to inhibit the binding of 125I-Lol p IV to serum IgE antibodies of a grass-allergic patient. Many of these fractions inhibited the binding between the native allergen and IgE antibodies in a dose-dependent manner. The inhibitions were specific, i.e., the fractions did not inhibit the binding between 125I-Lol p I (a group-I ryegrass pollen allergen) and the IgE antibodies present in the allergic human serum. The possibility that the allergenic peptide fractions were contaminated by the native undegraded allergen, which might have accounted for the observed inhibition, was ruled out by the fact that the native allergen could not be detected by SDS-PAGE and the elution profiles of allergenically active peptides did not coincide with that of native allergen. One of the allergenic sites recognized by monoclonal antibody (Mab) 90, i.e., site A, was located in HPLC fractions 90-100 while another allergenic site B (recognized by Mab 12) appeared to be lost following the sequential digestion of Lol p IV with CNBr and trypsin.

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

    Science.gov (United States)

    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.

  14. Bioinformatics analysis to assess potential risks of allergenicity and toxicity of HRAP and PFLP proteins in genetically modified bananas resistant to Xanthomonas wilt disease.

    Science.gov (United States)

    Jin, Yuan; Goodman, Richard E; Tetteh, Afua O; Lu, Mei; Tripathi, Leena

    2017-11-01

    Banana Xanthomonas wilt (BXW) disease threatens banana production and food security throughout East Africa. Natural resistance is lacking among common cultivars. Genetically modified (GM) bananas resistant to BXW disease were developed by inserting the hypersensitive response-assisting protein (Hrap) or/and the plant ferredoxin-like protein (Pflp) gene(s) from sweet pepper (Capsicum annuum). Several of these GM banana events showed 100% resistance to BXW disease under field conditions in Uganda. The current study evaluated the potential allergenicity and toxicity of the expressed proteins HRAP and PFLP based on evaluation of published information on the history of safe use of the natural source of the proteins as well as established bioinformatics sequence comparison methods to known allergens (www.AllergenOnline.org and NCBI Protein) and toxins (NCBI Protein). The results did not identify potential risks of allergy and toxicity to either HRAP or PFLP proteins expressed in the GM bananas that might suggest potential health risks to humans. We recognize that additional tests including stability of these proteins in pepsin assay, nutrient analysis and possibly an acute rodent toxicity assay may be required by national regulatory authorities. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. DermAll nanomedicine for allergen-specific immunotherapy.

    Science.gov (United States)

    Garaczi, Edina; Szabó, Kornélia; Francziszti, László; Csiszovszki, Zsolt; Lőrincz, Orsolya; Tőke, Enikő R; Molnár, Levente; Bitai, Tamás; Jánossy, Tamás; Bata-Csörgő, Zsuzsanna; Kemény, Lajos; Lisziewicz, Julianna

    2013-11-01

    Allergen-specific immunotherapy (ASIT) the only disease-modifying treatment for IgE-mediated allergies is characterized with long treatment duration and high risk of side effects. We investigated the safety, immunogenicity and efficacy of a novel ASIT, called DermAll, in an experimental allergic rhinitis model. We designed and characterized DermAll-OVA, a synthetic plasmid pDNA/PEIm nanomedicine expressing ovalbumin (OVA) as model allergen. DermAll-OVA was administered topically with DermaPrep device to target Langerhans cells. To detect the clinical efficacy of DermAll ASIT we quantified the nasal symptoms and characterized the immunomodulatory activity of DermAll ASIT by measuring cytokine secretion after OVA-stimulation of splenocytes and antibodies from the sera. In allergic mice DermAll ASIT was as safe as Placebo, balanced the allergen-induced pathogenic TH2-polarized immune responses, and decreased the clinical symptoms by 52% [32%, 70%] compared to Placebo. These studies suggest that DermAll ASIT is safe and should significantly improve the immunopathology and symptoms of allergic diseases. A novel allergen-specific immunotherapy for IgE-mediated allergies is presented in this paper, using an experimental allergic rhinitis model and a synthetic plasmid pDNA/PEIm nanomedicine expressing ovalbumin as model allergen. Over 50% reduction of symptoms was found as the immune system's balance was favorably altered toward more TH2-polarized immune responses. Copyright © 2013 Elsevier Inc. All rights reserved.

  16. Environmental contact factors in eczema and the results of patch testing Chinese patients with a modified European standard series of allergens.

    Science.gov (United States)

    Li, Lin-Feng; Guo, Jing; Wang, Jing

    2004-07-01

    Environmental contact factors in eczema were investigated in China by clinical questionnaire and patch testing patients with a modified European standard series of allergens. 217 consecutive eczema patients were studied. Contact dermatitis (CD) was clinically diagnosed in 30% of the patients. Among the patients patch tested, 46 patients had clinically diagnosed allergic CD (ACD), 20 patients clinically had non-ACD (NACD) (including 16 cases of irritant contact dermatitis, 1 case of phototoxic contact reaction and 3 cases of asteatotic eczema) and 115 patients had clinically suspected ACD. 45 patients (98%) in the ACD group went on to have relevant patch test results. The most common ACD was from metals, fragrance materials, cosmetics and rubber materials. The most common contact allergens identified were nickel, fragrance mix, para-phenylenediamine (PPD), carba mix and thimerosal. No adverse reactions were observed to patch testing, except for pruritus in patch-test-positive patients. The positive rate of patch testing in ACD was much higher than that in NACD (98% versus 15%, P China.

  17. Fish allergens at a glance: variable allergenicity of parvalbumins, the major fish allergens.

    Science.gov (United States)

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1) isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases, and fish gelatin, seem to be important allergens. New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings were useful for the advancement of the IgE-based diagnosis and also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

  18. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    Directory of Open Access Journals (Sweden)

    Annette eKuehn

    2014-04-01

    Full Text Available Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand, some individuals have IgE antibodies directed against unique, species-specific parvalbumin epitopes, and these patients show clinical symptoms only with certain fish species. Furthermore, different parvalbumin isoforms and isoallergens are present in the same fish and might display variable allergenicity. This was shown for salmon homologs, where only a single parvalbumin (beta-1 isoform was identified as allergen in specific patients. In addition to the parvalbumins, several other fish proteins, enolases, aldolases and fish gelatin, seem to be important allergens.New clinical and molecular insights advanced the knowledge and understanding of fish allergy in the last years. These findings will be useful for the advancement of the IgE-based diagnosis but also for the management of fish allergies consisting of advice and treatment of fish-allergic patients.

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

    DEFF Research Database (Denmark)

    Bøgh, Katrine Lindholm; Madsen, Charlotte Bernhard

    2016-01-01

    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......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...

  20. Airborne seafood allergens as a cause of occupational allergy and asthma.

    Science.gov (United States)

    Lopata, Andreas L; Jeebhay, Mohamed F

    2013-06-01

    Occupational allergy and asthma is a serious adverse health outcome affecting seafood-processing workers. Allergic reactions are directed to two major seafood groups: fish and shellfish, with the latter group comprising crustaceans and molluscs. Several allergenic proteins have been identified in these different groups, but few have been characterised on a molecular level. Parvalbumin appears to be the major fish allergen, while tropomyosin the major crustacean allergen. Other IgE-binding proteins have also been identified in molluscs and other seafood-associated agents (e.g. Anisakis sp), although their molecular nature has not been characterised. Aerosolised allergens can be identified and quantified using immunological and chemical approaches, detecting levels as low as 10 ng/m(3). This contemporary review discusses interesting and recent findings in the area of occupational seafood allergy including high-risk occupations, environmental risk factors for airborne exposures, major and minor allergens implicated and innovative approaches in diagnosing and managing occupational allergy and asthma associated with seafood processing.

  1. Fractionation and analysis of allergenicity of allergens from Prosopis juliflora pollen.

    Science.gov (United States)

    Thakur, I S

    1989-01-01

    Prosopis juliflora pollen allergen extract was prepared, and its crude allergen extract was fractionated by Sephadex G-100 gel filtration. Six different fractions were obtained which was confirmed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Protein and carbohydrate content of each fraction were estimated. Fraction E (MW 20,000) showed a 25% carbohydrate concentration. The amino acid analysis indicated that this fraction was rich in glutamic acid and alanine. Antigenicity or allergenicity of fractionated allergens were checked by gel diffusion test, rocket immunoelectrophoresis, skin prick test, and radioallergosorbent test. All these test indicate that fraction E consisted mainly of allergenic molecules (MW 20,000) of P. juliflora pollen.

  2. Allergenicity assessment of apple cultivars: hurdles in quantifying labile fruit allergens

    NARCIS (Netherlands)

    Zuidmeer, L.; van Leeuwen, W. A.; Kleine Budde, I.; Breiteneder, H.; Ma, Y.; Mills, C.; Sancho, A. I.; Meulenbroek, E. J.; van de Weg, E.; Gilissen, L.; Ferreira, F.; Hoffmann-Sommergruber, K.; van Ree, R.

    2006-01-01

    BACKGROUND: Assessment of allergenicity of foods is important for allergic consumers and regulators. Immunoassays to measure major food allergens are widely applied, often giving variable results. Using the major apple allergen Mal d 1 as a model, we aimed to establish at the molecular level why

  3. Chemical composition of silica-based biocidal modifier

    Directory of Open Access Journals (Sweden)

    Grishina Anna Nikolaevna

    2016-11-01

    Full Text Available Increase of the amount of fungi spores and micotixines causes the increase in the number of different diseases. Because of this, ensuring the biological safety in buildings is becoming more and more important today. The preferred way to guarantee the biological safety of a building is to employ modern building materials that prevent the settlement of the fungi colonies on the inner surfaces of walls. Such building materials can be produced using novel biocidal modifiers that allow controlling the number of microorganisms on the surface and in the bulk of a composite construction. The precipitation product of zinc hydrosilicates and sodium sulfate is one of the mentioned modifiers. Till now, the exact chemical composition of such precipitation product is controversial; it is obvious, though, that the efficacy of the biocidal modifier is mostly determined by the type of the copper compounds. In the present work an integrated approach is used for the investigation of the chemical composition of the biocidal modifier. Such an approach consists in the examination of the modifier’s composition by means of different, yet complementary, research methods: X-ray diffraction, infrared spectroscopy and DTA. It is shown that the chemical composition of the modifier mainly depends on the amount of precipitant. X-ray diffraction reveals that the major part of the modifier is represented by amorphous phase. Along with the increase of the precipitant’s amount the crystalline phase Zn4SO4(OH6•xH2O formation takes place. Such a crystalline phase is not appropriate as a component of the biocidal modifier. Another two methods - DTA and IR spectroscopy - reveal that the amorphous phase consists essentially of zinc hydrosilicates.

  4. Effective Allergen Management : Precautionary (may contain) allergen labeling; when to apply?

    NARCIS (Netherlands)

    Zandvoort. M.M.J. van

    2013-01-01

    When do you label food products as having been possibly cross contaminated by allergens? TNO can help you to develop a quantitative risk management guidance for food allergens, based on a unique method that quantifies the risk of food allergen traces in products and validated data on thresholds.

  5. Biosorption of uranium by chemically modified Rhodotorula glutinis

    International Nuclear Information System (INIS)

    Bai Jing; Yao Huijun; Fan Fangli; Lin Maosheng; Zhang Lina; Ding Huajie; Lei Fuan; Wu Xiaolei; Li, Xiaofei; Guo Junsheng; Qin Zhi

    2010-01-01

    The present paper reports the biosorption of uranium onto chemically modified yeast cells, Rhodotorula glutinis, in order to study the role played by various functional groups in the cell wall. Esterification of the carboxyl groups and methylation of the amino groups present in the cells were carried out by methanol and formaldehyde treatment, respectively. The uranium sorption capacity increased 31% for the methanol-treated biomass and 11% for the formaldehyde-treated biomass at an initial uranium concentration of 140 mg/L. The enhancement of uranium sorption capacity was investigated by Fourier transform infrared (FTIR) spectroscopy analysis, with amino and carboxyl groups were determined to be the important functional groups involved in uranium binding. The biosorption isotherms of uranium onto the raw and chemically modified biomass were also investigated with varying uranium concentrations. Langmuir and Freundlich models were well able to explain the sorption equilibrium data with satisfactory correlation coefficients higher than 0.9. -- Research highlights: → Uranium biosorption on to chemically modified yeast cells → Cells before and after uranium sorption were investigate by FTIR spectroscopy → Amino and carboxyl groups were important functional groups involved in uranium binding → The sorption equilibrium date of raw and chemically modified biomass fitted well with Langmuir and Freundlich models

  6. Biosorption of uranium by chemically modified Rhodotorula glutinis

    Energy Technology Data Exchange (ETDEWEB)

    Bai Jing, E-mail: baijing@impcas.ac.c [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Yao Huijun [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Fan Fangli; Lin Maosheng [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Zhang Lina; Ding Huajie; Lei Fuan; Wu Xiaolei [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Li, Xiaofei [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Guo Junsheng; Qin Zhi [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China)

    2010-11-15

    The present paper reports the biosorption of uranium onto chemically modified yeast cells, Rhodotorula glutinis, in order to study the role played by various functional groups in the cell wall. Esterification of the carboxyl groups and methylation of the amino groups present in the cells were carried out by methanol and formaldehyde treatment, respectively. The uranium sorption capacity increased 31% for the methanol-treated biomass and 11% for the formaldehyde-treated biomass at an initial uranium concentration of 140 mg/L. The enhancement of uranium sorption capacity was investigated by Fourier transform infrared (FTIR) spectroscopy analysis, with amino and carboxyl groups were determined to be the important functional groups involved in uranium binding. The biosorption isotherms of uranium onto the raw and chemically modified biomass were also investigated with varying uranium concentrations. Langmuir and Freundlich models were well able to explain the sorption equilibrium data with satisfactory correlation coefficients higher than 0.9. -- Research highlights: {yields} Uranium biosorption on to chemically modified yeast cells {yields} Cells before and after uranium sorption were investigate by FTIR spectroscopy {yields} Amino and carboxyl groups were important functional groups involved in uranium binding {yields} The sorption equilibrium date of raw and chemically modified biomass fitted well with Langmuir and Freundlich models

  7. [Genetically modified food and allergies - an update].

    Science.gov (United States)

    Niemann, Birgit; Pöting, Annette; Braeuning, Albert; Lampen, Alfonso

    2016-07-01

    Approval by the European Commission is mandatory for placing genetically modified plants as food or feed on the market in member states of the European Union (EU). The approval is preceded by a safety assessment based on the guidance of the European Food Safety Authority EFSA. The assessment of allergenicity of genetically modified plants and their newly expressed proteins is an integral part of this assessment process. Guidance documents for the assessment of allergenicity are currently under revision. For this purpose, an expert workshop was conducted in Brussels on June 17, 2015. There, methodological improvements for the assessment of coeliac disease-causing properties of proteins, as well as the use of complex models for in vitro digestion of proteins were discussed. Using such techniques a refinement of the current, proven system of allergenicity assessment of genetically modified plants can be achieved.

  8. Application of scientific criteria to food allergens of public health importance.

    Science.gov (United States)

    Chung, Y J; Ronsmans, S; Crevel, R W R; Houben, G F; Rona, R J; Ward, R; Baka, A

    2012-11-01

    Scientific criteria for identifying allergenic foods of public health importance (Björkstén, B., Crevel, R., Hischenhuber, C., Løvik, M., Samuels, F., Strobel, S., Taylor, S.L., Wal, J.-M., Ward, R., 2008. Criteria for identifying allergenic foods of public health importance. Regulatory Toxicology and Pharmacology 51(1), 42-52) have been further refined to incorporate an assessment of the strength of available scientific evidence (van Bilsen, J.H., Ronsmans, S., Crevel, R.W., Rona, R.J., Przyrembel, H., Penninks, A.H., Contor, L., Houben, G.F., 2011. Evaluation of scientific criteria for identifying allergenic food of public health importance. Regulatory Toxicology and Pharmacology 60, 281-289). A multi-disciplinary group was invited to critically test the refined approach. They independently evaluated selected publications on coconut, soy and/or peanut allergy, scored them using the newly developed level of evidence criteria, and debated proposed approaches for combining and utilising the scores to measure the overall impact of an allergen in public health impact assessments. The evaluation of selected publications using the modified criteria produced a relatively consistent result across the experts. These refined criteria were judged to be a way forward for the identification of allergenic foods of public health importance, and for prioritisation of allergen risk management and future data gathering. The debate to combine available evidence when assessing whether an allergenic food is of sufficient public health importance to warrant active management led to proposals on how to weight and combine evidence on allergen severity, potency and prevalence. The refined criteria facilitate a debate to find a meaningful sequence of steps to summarise the available information in relation to a food allergen. Copyright © 2012 ILSI Europe. Published by Elsevier Inc. All rights reserved.

  9. Effect of reagins and allergen extracts on radioallergosorbent assays for mite allergen

    International Nuclear Information System (INIS)

    Tovey, E.R.; Vandenberg, R.A.

    1978-01-01

    The reproducibility of the radioallergosorbent (RAST) inhibition and direct binding assays with mite allergen were investigated in the presence of heterogeneous extracts and non-mite sensitive atopic sera. Both contain components similar to potential contaminants which would occur in the assay of mite allergen and dust allergen extracts. The standardized inhibition and direct binding assays employed had a day to day (n = 4) coefficient of variation [(s.d. x 100)/mean] of 15% and 24% respectively. The inhibition assay for mite allergen was reproducible in the presence of protein concentrations of added plant, fungal, arthropod and animal extracts in excess of the protein concentrations that occur under the operational mite assay conditions. The mite inhibition assay was also reproducible in the presence of non-mite allergen extracts, with and without additional sera containing IgE specific for the non0mite allergens. The binding of a constant quantity of mite allergen to the activated solid phase in the direct binding assay was reproducible in the presence of added bovine serum albumin, and of a fungal or arthropod extract, representing the heterogeneous components of an allergen extract at the concentrations of total protein known to occur in the direct binding assay of mite extracts. (author)

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

    Science.gov (United States)

    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 (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.

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

    Science.gov (United States)

    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.

  12. Current (Food) Allergenic Risk Assessment: Is It Fit for Novel Foods? Status Quo and Identification of Gaps.

    Science.gov (United States)

    Mazzucchelli, Gabriel; Holzhauser, Thomas; Cirkovic Velickovic, Tanja; Diaz-Perales, Araceli; Molina, Elena; Roncada, Paola; Rodrigues, Pedro; Verhoeckx, Kitty; Hoffmann-Sommergruber, Karin

    2018-01-01

    Food allergies are recognized as a global health concern. In order to protect allergic consumers from severe symptoms, allergenic risk assessment for well-known foods and foods containing genetically modified ingredients is installed. However, population is steadily growing and there is a rising need to provide adequate protein-based foods, including novel sources, not yet used for human consumption. In this context safety issues such as a potential increased allergenic risk need to be assessed before marketing novel food sources. Therefore, the established allergenic risk assessment for genetically modified organisms needs to be re-evaluated for its applicability for risk assessment of novel food proteins. Two different scenarios of allergic sensitization have to be assessed. The first scenario is the presence of already known allergenic structures in novel foods. For this, a comparative assessment can be performed and the range of cross-reactivity can be explored, while in the second scenario allergic reactions are observed toward so far novel allergenic structures and no reference material is available. This review summarizes the current analytical methods for allergenic risk assessment, highlighting the strengths and limitations of each method and discussing the gaps in this assessment that need to be addressed in the near future. © 2017 The Authors. Published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Increased cell proliferation in spleen and lymph nodes peripheral to contact allergen application site

    International Nuclear Information System (INIS)

    Chipinda, Itai; Anderson, Stacey E.; Butterworth, Leon F.; Beezhold, Donald; Siegel, Paul D.

    2009-01-01

    The local lymph node assay (LLNA) is widely used to identify chemicals that are contact sensitizers. The assay involves dosing mice with the chemical on both ears and pooling the superficial parotid lymph nodes for assessment of lymphocyte proliferation as a marker of sensitization. The present study explored potential reduction in animal usage by dosing one ear with the allergen and the other with vehicle-only. The respective draining lymph nodes were processed separately for tritiated thymidine ( 3 H-TdR) incorporation. Cell proliferation in proper axillary and renal nodes, as well as in the spleen was also assessed. Cross-contamination of the chemicals from the dosed ears to other parts of the body via preening was prevented by dosing restrained animals and washing off the residual chemical with saline after 4 h. Dosing the left ear with 0.02% oxazolone (OX) on unrestrained animals resulted in marked cell proliferation in its draining lymph node (stimulation index, SI = 12.8) and in the lymph node draining the contra-lateral vehicle-dosed ear (SI = 6), as well as the proper axillary lymph nodes (SI = 3.3). Increased 3 H-TdR incorporation was not observed in the renal lymph nodes (SI = 1.1). Similar stimulation of cells was observed in the lymph node draining the ear contra-lateral to the 30% hexylcinnamaldehyde (HCA)-dosed ear. Increased proliferative activity was observed in contra-lateral draining lymph nodes of restrained mice demonstrating that these results cannot be attributed to cross-contamination of adjacent skin. A significant increase in proliferation of splenocytes was also observed. It is concluded that dermal application of a contact allergen, as exemplified by OX and HCA, may induce cell proliferation in the neighboring lymph nodes and spleen indicative of hapten and/or haptenated proteins diffusing through the skin to peripheral nodes and the blood to produce systemic sensitization. It is also possible that lymphatic capillaries may communicate

  14. Food processing and allergenicity.

    Science.gov (United States)

    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.

  15. Bioanalytical methods for food allergy diagnosis, allergen detection and new allergen discovery.

    Science.gov (United States)

    Gasilova, Natalia; Girault, Hubert H

    2015-01-01

    For effective monitoring and prevention of the food allergy, one of the emerging health problems nowadays, existing diagnostic procedures and allergen detection techniques are constantly improved. Meanwhile, new methods are also developed, and more and more putative allergens are discovered. This review describes traditional methods and summarizes recent advances in the fast evolving field of the in vitro food allergy diagnosis, allergen detection in food products and discovery of the new allergenic molecules. A special attention is paid to the new diagnostic methods under laboratory development like various immuno- and aptamer-based assays, including immunoaffinity capillary electrophoresis. The latter technique shows the importance of MS application not only for the allergen detection but also for the allergy diagnosis.

  16. Chemically-modified cellulose paper as a microstructured catalytic reactor.

    Science.gov (United States)

    Koga, Hirotaka; Kitaoka, Takuya; Isogai, Akira

    2015-01-15

    We discuss the successful use of chemically-modified cellulose paper as a microstructured catalytic reactor for the production of useful chemicals. The chemical modification of cellulose paper was achieved using a silane-coupling technique. Amine-modified paper was directly used as a base catalyst for the Knoevenagel condensation reaction. Methacrylate-modified paper was used for the immobilization of lipase and then in nonaqueous transesterification processes. These catalytic paper materials offer high reaction efficiencies and have excellent practical properties. We suggest that the paper-specific interconnected microstructure with pulp fiber networks provides fast mixing of the reactants and efficient transport of the reactants to the catalytically-active sites. This concept is expected to be a promising route to green and sustainable chemistry.

  17. Chemically-Modified Cellulose Paper as a Microstructured Catalytic Reactor

    Directory of Open Access Journals (Sweden)

    Hirotaka Koga

    2015-01-01

    Full Text Available We discuss the successful use of chemically-modified cellulose paper as a microstructured catalytic reactor for the production of useful chemicals. The chemical modification of cellulose paper was achieved using a silane-coupling technique. Amine-modified paper was directly used as a base catalyst for the Knoevenagel condensation reaction. Methacrylate-modified paper was used for the immobilization of lipase and then in nonaqueous transesterification processes. These catalytic paper materials offer high reaction efficiencies and have excellent practical properties. We suggest that the paper-specific interconnected microstructure with pulp fiber networks provides fast mixing of the reactants and efficient transport of the reactants to the catalytically-active sites. This concept is expected to be a promising route to green and sustainable chemistry.

  18. Allergenicity assessment strategy for novel food proteins and protein sources.

    Science.gov (United States)

    Verhoeckx, Kitty; Broekman, Henrike; Knulst, André; Houben, Geert

    2016-08-01

    To solve the future food insecurity problem, alternative and sustainable protein sources (e.g. insects, rapeseed, fava bean and algae) are now being explored for the production of food and feed. To approve these novel protein sources for future food a comprehensive risk assessment is needed according to the European food legislation. Allergenicity risk assessment might pose some major difficulties, since detailed guidance on how to assess the allergenic potential of novel foods is not available. At present, the approach relies mostly on the guidance of allergenicity assessment for genetically modified (GM) plant foods. The most recent one was proposed by EFSA (2010 and 2011); "weight-of-evidence approach". However this guidance is difficult to interpret, not completely applicable or validated for novel foods and therefore needs some adjustments. In this paper we propose a conceptual strategy which is based on the "weight-of-evidence approach" for food derived from GM plants and other strategies that were previously published in the literature. This strategy will give more guidance on how to assess the allergenicity of novel food proteins and protein sources. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. The effect of marimastat, a metalloprotease inhibitor, on allergen-induced asthmatic hyper-reactivity

    International Nuclear Information System (INIS)

    Bruce, Colleen; Thomas, Paul S.

    2005-01-01

    This pilot study was designed to assess whether a synthetic matrix metalloproteinase (MMP) inhibitor has anti-inflammatory properties in mild asthma. Tumor necrosis factor alpha (TNFα) has been shown to be an important cytokine in the pathogenesis of allergic airway inflammatory responses, and its release can be inhibited by MMP inhibitors. Twelve atopic asthmatic subjects received the MMP inhibitor marimastat (5 mg) or placebo, twice daily for 3 weeks, separated by a 6-week washout period in a randomized, double-blind, cross-over manner. All subjects underwent an allergen inhalation provocation test to Dermatophagoides pteronyssinus before and after each study phase. Spirometry, exhaled NO (eNO) levels, differential sputum cell counts, an asthma symptom questionnaire, peak flow, and β 2 -agonist usage were measured. Nine subjects completed the study, and, when compared with placebo, marimastat reduced bronchial hyper-responsiveness to inhaled allergen in these subjects from an allergen PC 20 of 22.2 AU/ml (95%CI 11.7-32.6) to 17.0 AU/ml (95%CI 7.6-26.4, P = 0.02). The marimastat phase showed a nonsignificant fall in sputum inflammatory cells. Marimastat did not modify eNO, FEV 1 , asthma symptoms, or albuterol usage. In conclusion, airway responsiveness to allergen may be modified by a MMP inhibitor, perhaps via TNFα playing a role in airway inflammation and remodeling

  20. Detection of major food allergens in amniotic fluid: initial allergenic encounter during pregnancy.

    Science.gov (United States)

    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.

  1. Footwear dermatitis - Clinical patterns and contact allergens

    Directory of Open Access Journals (Sweden)

    Handa S

    1991-01-01

    Full Text Available Thirty patients suspected of contact dermatitis to footwear studied to evaluate various clinical presentations and possible sensitizers. ′V′ chappals and sandals were suspected alone in 12, a combination of open and closed shoes in 15 and closed shoes alone in 3 patients. Commonest affected sites were dorsa of feet and toes in 14 and dorsa of feet corresponding to the shape of footwear in 12 patients. Patch tests were done using a battery of sixteen allergens. Positive patch tests were seen in 29 patients. Rubber chemicals were the commonest allergens detected in 26 patients, dyes in 10,leather in 6, glues and neoprene cements in 4 and rubber material from suspected footwear as such in 4 patients respectively.

  2. Mechanisms of Allergen-Specific Immunotherapy and Novel Ways for Vaccine Development

    Directory of Open Access Journals (Sweden)

    Marek Jutel

    2013-01-01

    Full Text Available Allergen-specific immunotherapy (SIT is the only available curative treatment of allergic diseases. Recent evidence provided a plausible explanation to its multiple mechanisms inducing both rapid desensitization and long-term allergen-specific immune tolerance, and suppression of allergic inflammation in the affected tissues. During SIT, peripheral tolerance is induced by the generation of allergen-specific regulatory T cells, which suppress proliferative and cytokine responses against the allergen of interest. Regulatory T cells are characterized by IL-10 and TGF-beta secretion and expression of important cell surface suppressive molecules such as cytotoxic T lymphocyte antigen-4 and programmed death-1 that directly or indirectly influence effector cells of allergic inflammation, such as mast cells, basophils and eosinophils. Regulatory T cells and particularly IL-10 also have an influence on B cells, suppressing IgE production and inducing the production of blocking type IgG4 antibodies. In addition, development of allergen-specific B regulatory cells that produce IL-10 and develop into IgG4 producing plasma cells represent essential players in peripheral tolerance. These findings together with the new biotechnological approaches create a platform for development of the advanced vaccines. Moreover, reliable biomarkers could be selected and validated with the intention to select the patients who will benefit most from this immune-modifying treatment. Thus, allergen-SIT could provide a complete cure for a larger number of allergic patients and novel preventive approaches need to be elaborated.

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

    Science.gov (United States)

    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

  4. Legumin allergens from peanuts and soybeans: Effects of denaturation and aggregation on allergenicity

    NARCIS (Netherlands)

    Boxtel, E.L. van; Broek, L.A.M. van den; Koppelman, S.J.; Gruppen, H.

    2008-01-01

    Legumin proteins Ara h 3 from peanuts and glycinin from soybeans are increasingly described as important allergens. The stability of an allergen's IgE binding capacity towards heating and digestion is considered an important characteristic for food allergens. We investigated the effects of heating

  5. Legumin allergens from peanuts and soybeans : Effects of denaturation and aggregation on allergenicity

    NARCIS (Netherlands)

    Boxtel, van E.L.; Broek, van den L.A.M.; Koppelman, S.J.; Gruppen, H.

    2008-01-01

    Legumin proteins Ara h 3 from peanuts and glycinin from soybeans are increasingly described as important allergens. The stability of an allergen's IgE binding capacity towards heating and digestion is considered an important characteristic for food allergens. We investigated the effects of heating

  6. Calculation of Multiphase Chemical Equilibrium by the Modified RAND Method

    DEFF Research Database (Denmark)

    Tsanas, Christos; Stenby, Erling Halfdan; Yan, Wei

    2017-01-01

    method. The modified RAND extends the classical RAND method from single-phase chemical reaction equilibrium of ideal systems to multiphase chemical equilibrium of nonideal systems. All components in all phases are treated in the same manner and the system Gibbs energy can be used to monitor convergence....... This is the first time that modified RAND was applied to multiphase chemical equilibrium systems. The combined algorithm was tested using nine examples covering vapor–liquid (VLE) and vapor–liquid–liquid equilibria (VLLE) of ideal and nonideal reaction systems. Successive substitution provided good initial......A robust and efficient algorithm for simultaneous chemical and phase equilibrium calculations is proposed. It combines two individual nonstoichiometric solving procedures: a nested-loop method with successive substitution for the first steps and final convergence with the second-order modified RAND...

  7. Subchronic toxicity study in vivo and allergenicity study in vitro for genetically modified rice that expresses pharmaceutical protein (human serum albumin).

    Science.gov (United States)

    Sheng, Yao; Qi, Xiaozhe; Liu, Yifei; Guo, Mingzhang; Chen, Siyuan; He, Xiaoyun; Huang, Kunlun; Xu, Wentao

    2014-10-01

    Genetically modified (GM) crops that express pharmaceutical proteins have become an important focus of recent genetic engineering research. Food safety assessment is necessary for the commercial development of these crops. Subchronic toxicity study in vivo and allergenicity study in vitro were designed to evaluate the food safety of the rice variety expressing human serum albumin (HSA). Animals were fed rodent diets containing 12.5%, 25.0% and 50.0% GM or non-GM rice for 90 days. The composition analysis of the GM rice demonstrated several significant differences. However, most of the differences remained within the ranges reported in the literature. In the animal study, a range of indexes including clinical observation, feed efficiency, hematology, serum chemistry, organ weights and histopathology were examined. Random changes unrelated to the GM rice exposure, within the range of historical control values and not associated with any signs of illness were observed. The results of heat stability and in vitro digestion of HSA indicated no evidence of potential allergenicity of the protein. Overall, the results of these studies suggest that the GM rice appears to be safe as a dietary ingredient when it is used at up to 50% in the diet on a subchronic basis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. The use of simultaneous chemical precipitation in modified activated ...

    African Journals Online (AJOL)

    The use of simultaneous chemical precipitation in modified activated sludge systems exhibiting biological excess phosphate removal: Part 6: Modelling of simultaneous chemical-biological P removal - review of existing models.

  9. Fish allergens at a glance: Variable allergenicity of parvalbumins, the major fish allergens

    OpenAIRE

    Annette eKuehn; Ines eSwoboda; Karthik eArumugam; Christiane eHilger; François eHentges; François eHentges

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  10. Fish Allergens at a Glance: Variable Allergenicity of Parvalbumins, the Major Fish Allergens

    OpenAIRE

    Kuehn, Annette; Swoboda, Ines; Arumugam, Karthik; Hilger, Christiane; Hentges, François

    2014-01-01

    Fish is a common trigger of severe, food-allergic reactions. Only a limited number of proteins induce specific IgE-mediated immune reactions. The major fish allergens are the parvalbumins. They are members of the calcium-binding EF-hand protein family characterized by a conserved protein structure. They represent highly cross-reactive allergens for patients with specific IgE to conserved epitopes. These patients might experience clinical reactions with various fish species. On the other hand,...

  11. Artificial Specific Binders Directly Recovered from Chemically Modified Nucleic Acid Libraries

    Directory of Open Access Journals (Sweden)

    Yuuya Kasahara

    2012-01-01

    Full Text Available Specific binders comprised of nucleic acids, that is, RNA/DNA aptamers, are attractive functional biopolymers owing to their potential broad application in medicine, food hygiene, environmental analysis, and biological research. Despite the large number of reports on selection of natural DNA/RNA aptamers, there are not many examples of direct screening of chemically modified nucleic acid aptamers. This is because of (i the inferior efficiency and accuracy of polymerase reactions involving transcription/reverse-transcription of modified nucleotides compared with those of natural nucleotides, (ii technical difficulties and additional time and effort required when using modified nucleic acid libraries, and (iii ambiguous efficacies of chemical modifications in binding properties until recently; in contrast, the effects of chemical modifications on biostability are well studied using various nucleotide analogs. Although reports on the direct screening of a modified nucleic acid library remain in the minority, chemical modifications would be essential when further functional expansion of nucleic acid aptamers, in particular for medical and biological uses, is considered. This paper focuses on enzymatic production of chemically modified nucleic acids and their application to random screenings. In addition, recent advances and possible future research are also described.

  12. Artificial specific binders directly recovered from chemically modified nucleic acid libraries.

    Science.gov (United States)

    Kasahara, Yuuya; Kuwahara, Masayasu

    2012-01-01

    Specific binders comprised of nucleic acids, that is, RNA/DNA aptamers, are attractive functional biopolymers owing to their potential broad application in medicine, food hygiene, environmental analysis, and biological research. Despite the large number of reports on selection of natural DNA/RNA aptamers, there are not many examples of direct screening of chemically modified nucleic acid aptamers. This is because of (i) the inferior efficiency and accuracy of polymerase reactions involving transcription/reverse-transcription of modified nucleotides compared with those of natural nucleotides, (ii) technical difficulties and additional time and effort required when using modified nucleic acid libraries, and (iii) ambiguous efficacies of chemical modifications in binding properties until recently; in contrast, the effects of chemical modifications on biostability are well studied using various nucleotide analogs. Although reports on the direct screening of a modified nucleic acid library remain in the minority, chemical modifications would be essential when further functional expansion of nucleic acid aptamers, in particular for medical and biological uses, is considered. This paper focuses on enzymatic production of chemically modified nucleic acids and their application to random screenings. In addition, recent advances and possible future research are also described.

  13. Chemically modified graphene based supercapacitors for flexible and miniature devices

    Science.gov (United States)

    Ghosh, Debasis; Kim, Sang Ouk

    2015-09-01

    Rapid progress in the portable and flexible electronic devises has stimulated supercapacitor research towards the design and fabrication of high performance flexible devices. Recent research efforts for flexible supercapacitor electrode materials are highly focusing on graphene and chemically modified graphene owing to the unique properties, including large surface area, high electrical and thermal conductivity, excellent mechanical flexibility, and outstanding chemical stability. This invited review article highlights current status of the flexible electrode material research based on chemically modified graphene for supercapacitor application. A variety of electrode architectures prepared from chemically modified graphene are summarized in terms of their structural dimensions. Novel prototypes for the supercapacitor aiming at flexible miniature devices, i.e. microsupercapacitor with high energy and power density are highlighted. Future challenges relevant to graphene-based flexible supercapacitors are also suggested. [Figure not available: see fulltext.

  14. The Level of Sensitivity of Food Allergens

    Directory of Open Access Journals (Sweden)

    Iris Rengganis

    2011-06-01

    Full Text Available In recent years, the occurrence of allergy continues to increase rapidly both domestically and globally. World Allergy Organization (WAO revealed that 22% of the world population suffers from allergies, and this number increases every year. Food allergy is a condition caused by the reaction of IgE against substances (chemicals in food. Food allergy can interfere with brain function and body organ systems as well as affect the quality of life. The purpose of this study is to know the level of sensitivity of food allergens in the Immunology Allergy Poly RSCM in 2007. Data were collected from 208 patients who have medical records and went through skin prick tests in the Immunology Allergy Clinic RSCM in 2007. Univariate analysis was performed to describe the types of food allergens within groups of children and adults. Around 49% of the respondents were sensitive to food allergens. The types of foods that caused the most allergies for children and adults are respectively shrimp, egg white and cornstarch. Cow's milk and wheat flour are the types of food that caused most allergies for children only, whereas for adults, the food that caused the most allergies is crab.

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

    Science.gov (United States)

    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

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

    International Nuclear Information System (INIS)

    Joad, Jesse P.; Kott, Kayleen S.; Bric, John M.; Peake, Janice L.; Plopper, Charles G.; Schelegle, Edward S.; Gershwin, Laurel J.; Pinkerton, Kent E.

    2006-01-01

    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 relationship 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

  17. Allergens from fish and egg

    DEFF Research Database (Denmark)

    Poulsen, L.K.; Hansen, Tine Kjær; Norgaard, A.

    2001-01-01

    Allergens from fish and egg belong to some of the most frequent causes of food allergic reactions reported in the literature. Egg allergens have been described in both white and yolk, and the egg white proteins ovomucoid, ovalbumin, ovotransferrin and lysozyme have been adopted in the allergen...... nomenclature as Gal d1-d4. The most reported allergen from egg yolk seems to be alpha-livitin. In fish, the dominating allergen is the homologues of Gad c1 from cod, formerly described as protein M. A close cross-reactivity exists within different species of fish between this calcium-binding protein family...

  18. siRNAmod: A database of experimentally validated chemically modified siRNAs.

    Science.gov (United States)

    Dar, Showkat Ahmad; Thakur, Anamika; Qureshi, Abid; Kumar, Manoj

    2016-01-28

    Small interfering RNA (siRNA) technology has vast potential for functional genomics and development of therapeutics. However, it faces many obstacles predominantly instability of siRNAs due to nuclease digestion and subsequently biologically short half-life. Chemical modifications in siRNAs provide means to overcome these shortcomings and improve their stability and potency. Despite enormous utility bioinformatics resource of these chemically modified siRNAs (cm-siRNAs) is lacking. Therefore, we have developed siRNAmod, a specialized databank for chemically modified siRNAs. Currently, our repository contains a total of 4894 chemically modified-siRNA sequences, comprising 128 unique chemical modifications on different positions with various permutations and combinations. It incorporates important information on siRNA sequence, chemical modification, their number and respective position, structure, simplified molecular input line entry system canonical (SMILES), efficacy of modified siRNA, target gene, cell line, experimental methods, reference etc. It is developed and hosted using Linux Apache MySQL PHP (LAMP) software bundle. Standard user-friendly browse, search facility and analysis tools are also integrated. It would assist in understanding the effect of chemical modifications and further development of stable and efficacious siRNAs for research as well as therapeutics. siRNAmod is freely available at: http://crdd.osdd.net/servers/sirnamod.

  19. Content of Asthmagen Natural Rubber Latex Allergens in Commercial Disposable Gloves.

    Science.gov (United States)

    Bittner, C; Garrido, M V; Krach, L H; Harth, V

    The use of natural rubber latex (NRL) gloves in many occupations may lead to latex sensitization, allergic asthma, and skin reactions. Due to their good properties and environmental safety NRL gloves are still being used in the healthcare setting, but also in the food industry, by hairdressers, cleaners, etc. The aim of our study was to assess the protein and NRL allergen content in commercial gloves by different methods, including a new assay. Twenty commercially available NRL gloves were analyzed. Protein extraction was performed according to the international standard ASTM D-5712. Total protein content was measured with a modified Lowry method, NRL content with the CAP Inhibition Assay, the Beezhold ELISA Inhibition Assay, and an innovative ELISA with IgY-antibodies extracted from eggs of NRL-immunized hens (IgY Inhibition Assay). We found a high protein content in a range of 215.0-1304.7 μg/g in 8 out of the 20 NRL gloves. Seven of the 20 gloves were powdered, four of them with a high protein content. In gloves with high protein content, the immunological tests detected congruently high levels of NRL allergen. We conclude that a high percentage of commercially available NRL gloves still represent a risk for NRL allergy, including asthma. The modified Lowry Method allows to infer on the latex allergen content.

  20. Bioanalytical methods for food allergy diagnosis, allergen detection and new allergen discovery

    OpenAIRE

    Gasilova, Natalia; Girault, Hubert H

    2015-01-01

    For effective monitoring and prevention of the food allergy, one of the emerging health problems nowadays, existing diagnostic procedures and allergen detection techniques are constantly improved. Meanwhile, new methods are also developed, and more and more putative allergens are discovered. This review describes traditional methods and summarizes recent advances in the fast evolving field of the in vitro food allergy diagnosis, allergen detection in food products and discovery of the new all...

  1. Effects of nasal corticosteroids on boosts of systemic allergen-specific IgE production induced by nasal allergen exposure.

    Directory of Open Access Journals (Sweden)

    Cornelia Egger

    Full Text Available Allergen exposure via the respiratory tract and in particular via the nasal mucosa boosts systemic allergen-specific IgE production. Intranasal corticosteroids (INCS represent a first line treatment of allergic rhinitis but their effects on this boost of allergen-specific IgE production are unclear.Here we aimed to determine in a double-blind, placebo-controlled study whether therapeutic doses of an INCS preparation, i.e., nasal fluticasone propionate, have effects on boosts of allergen-specific IgE following nasal allergen exposure.Subjects (n = 48 suffering from grass and birch pollen allergy were treated with daily fluticasone propionate or placebo nasal spray for four weeks. After two weeks of treatment, subjects underwent nasal provocation with either birch pollen allergen Bet v 1 or grass pollen allergen Phl p 5. Bet v 1 and Phl p 5-specific IgE, IgG1-4, IgM and IgA levels were measured in serum samples obtained at the time of provocation and one, two, four, six and eight weeks thereafter.Nasal allergen provocation induced a median increase to 141.1% of serum IgE levels to allergens used for provocation but not to control allergens 4 weeks after provocation. There were no significant differences regarding the boosts of allergen-specific IgE between INCS- and placebo-treated subjects.In conclusion, the application of fluticasone propionate had no significant effects on the boosts of systemic allergen-specific IgE production following nasal allergen exposure.http://clinicaltrials.gov/NCT00755066.

  2. Environmental effects on allergen levels in commercially grown non-genetically modified soybeans: assessing variation across North America

    Directory of Open Access Journals (Sweden)

    Severin E. Stevenson

    2012-08-01

    Full Text Available Soybean (Glycine max is a hugely valuable soft commodity that generates tens of billions of dollars annually. This value is due in part to the balanced composition of the seed which is roughly 1:2:2 oil, starch and protein by weight. In turn, the seeds have many uses with various derivatives appearing broadly in processed food products. As is true with many edible seeds, soybeans contain proteins that are anti-nutritional factors and allergens. Soybean, along with milk, eggs, fish, crustacean shellfish, tree nuts, peanuts and wheat, elicit a majority of food allergy reactions in the United States. Soybean seed composition can be affected by breeding, environmental conditions (e.g. temperature, moisture, insect/pathogen load, and/or soil nutrient levels. The objective of this study was to evaluate the influence of genotype and environment on allergen and anti-nutritional proteins in soybean. To address genetic and environmental effects, four varieties of non-GM soybeans were grown in six geographically distinct regions of North America (Georgia, Iowa, Kansas, Nebraska, Ontario, and Pennsylvania. Absolute quantification of proteins by mass spectrometry can be achieved with a technique called multiple reaction monitoring (MRM, during which signals from an endogenous protein are compared to those from a synthetic heavy-labeled internal standard. Using MRM, eight allergens were absolutely quantified for each variety in each environment. Statistical analyses show that for most allergens, the effects of environment far outweigh the differences between varieties brought about by breeding.

  3. Molecular Allergen-Specific IgE Assays as a Complement to Allergen Extract-Based Sensitization Assessment

    NARCIS (Netherlands)

    Aalberse, Rob C.; Aalberse, Joost A.

    2015-01-01

    Molecular allergen-based component-resolved diagnostic IgE antibody tests have emerged in the form of singleplex assays and multiplex arrays. They use both native and recombinant allergen molecules, sometimes in combination with each other, to supplement allergen extract-based IgE antibody analyses.

  4. Spectrum of allergens for Japanese cedar pollinosis and impact of component-resolved diagnosis on allergen-specific immunotherapy

    Directory of Open Access Journals (Sweden)

    Takashi Fujimura

    2015-10-01

    Full Text Available The high prevalence of Japanese cedar pollinosis in Japan is associated with a negative impact on the quality of life of patients, as well as significant loss of productivity among the workforce in early spring, thus representing a serious social problem. Furthermore, the prevalence is increasing, and has risen by more than 10% in this decade. Cry j 1 and Cry j 2 were identified as the major allergens in Japanese cedar pollen (JCP, and in 2004, the existence of other major and minor allergens were revealed by a combination of two-dimensional electrophoresis and immunoblotting analysis. Allergenome analysis identified a chitinase, a lipid transfer protein, a serine protease, and an aspartic protease as novel IgE-reactive allergens in patients with JCP allergy. Thaumatin-like protein (Cry j 3 was shown to be homologous to Jun a 3, a major allergen from mountain cedar pollen. Isoflavone reductase-like protein was also characterized in a study of a JCP cDNA library. The characterization of component allergens is required to clarify the sensitizer or cross-reactive elicitor allergens for component-resolved diagnosis (CRD. Increasing evidence from numerous clinical trials indicates that CRD can be used to design effective allergen-specific immunotherapy. In this review, we summarize the eight characterized JCP allergens and discuss the impact of CRD and characterization of novel allergens on allergen-specific immunotherapy.

  5. ALLERGEN-SPECIFIC IMMUNOTHERAPY: VACCINES FOR ALLERGIC DISEASES

    Directory of Open Access Journals (Sweden)

    A. S. Fedorov

    2015-01-01

    via increased production of specific IgG antibodies, primarily of IgG4 subtype. The shift of balance between IgE and IgG4 towards IgG4 production is now considered a fundamental condition for successful ASIT. It has been proven that the allergen-specific IgG4 antibodies against IgE persist after discontinuation of the treatment and can provide long-term clinical tolerance. Modern prospectives for development of new forms and species of preparations for ASIT are also reviewed. Two groups of drugs for ASIT have been adopted for clinical practice until now, i.e., allergens and allergoids (allergens chemically modified by treatment with formaldehyde, in order to enhance their immunogenicity and to reduce the incidence of adverse allergic reactions associated with their application. Immunological mechanisms of SLIT (sublingual immunotherapy are subjected to special consideration. So far, SLIT is the safest and most promising option of ASIT today, its usage is most expedient in pediatric practice.

  6. In silico assessment of the potential allergenicity of transgenes used for the development of GM food crops.

    Science.gov (United States)

    Mishra, Ankita; Gaur, S N; Singh, B P; Arora, Naveen

    2012-05-01

    Genetically modified (GM) crops require allergenicity and toxicity assessment of the novel protein(s) to ensure complete safety to the consumers. These assessments are performed in accordance with the guidelines proposed by Codex (2003) and ICMR (2008). The guidelines recommend sequence homology analysis as a preliminary step towards allergenicity prediction, later in vitro experiments may be performed to confirm allergenicity. In the present study, an in silico approach is employed to evaluate the allergenic potential of six transgenes routinely used for the development of GM food crops. Among the genes studied, manganese superoxide dismutase (MnSOD) and osmotin shares greater than 90% identity with Hev b 10 and Cap a 1w, respectively. Chitinase shares greater than 70% identity with allergens namely Pers a 1 and Hev b 11, and fungal chitinase showed significant IgE binding with 7 of 75 patients' sera positive to different food extracts. Glucanases (alfalfa, wheat) and glycine betaine aldehyde dehydrogenase gene share 50% homology with allergens like - Ole e 9, Cla h 10 and Alt a 10. The results demonstrate the allergenic potential of six genes and can serve as a guide for selection of transgenes to develop GM crops. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. Allergen management in the food industry

    National Research Council Canada - National Science Library

    Boye, Joyce I; Godefroy, Samuel Benrejeb

    2010-01-01

    .... Starting with an introduction to food allergens, the book follows with sections on food allergen management during production and processing, guidelines for the processing of specific allergen-free...

  8. Mountain cedar allergens found in nonpollen tree parts.

    Science.gov (United States)

    Goetz, D W; Goetz, M A; Whisman, B A

    1995-09-01

    Mountain cedar (Juniperus ashei) pollen is the principal aeroallergen in south central Texas from late December through February. The major mountain cedar allergen is a 40-kD glycoprotein, gp40. To identify allergens in mountain cedar wood, leaves, and berries and to detect mountain cedar allergen in smoke from burning male or female trees. SDS-PAGE plus mountain cedar human sIgE and monoclonal antibody immunoblots identified mountain cedar allergens within pollen and nonpollen tree part extracts. IgE immunoblots identified a single wood allergen at 36 kD and three berry allergens at 36, 26-27, and 21 kD, in addition to known pollen allergens. Mountain cedar monoclonal antibody bound an allergen epitope present not only on 40, 33, and 28-kD pollen allergens, but also on 36 and 32-kD wood allergens, and the 26-27-kD berry allergen. Immunoblot studies detected no mountain cedar allergen in leaves and no allergen in smoke from burning male and female trees. Allergens constituted a much smaller percentage of extractable protein in wood and berries than in pollen. Mountain cedar berry allergen content is too small to give credence to the ingestion of berries as a folk medicine treatment of mountain cedar pollinosis. In addition, while smoke from burning mountain cedar trees may be irritating, it contains no allergens that could cause allergic rhinoconjunctivitis.

  9. Allergenic characterization of a novel allergen, homologous to chymotrypsin, from german cockroach.

    Science.gov (United States)

    Jeong, Kyoung Yong; Son, Mina; Lee, Jae Hyun; Hong, Chein Soo; Park, Jung Won

    2015-05-01

    Cockroach feces are known to be rich in IgE-reactive components. Various protease allergens were identified by proteomic analysis of German cockroach fecal extract in a previous study. In this study, we characterized a novel allergen, a chymotrypsin-like serine protease. A cDNA sequence homologous to chymotrypsin was obtained by analysis of German cockroach expressed sequence tag (EST) clones. The recombinant chymotrypsins from the German cockroach and house dust mite (Der f 6) were expressed in Escherichia coli using the pEXP5NT/TOPO vector system, and their allergenicity was investigated by ELISA. The deduced amino acid sequence of German cockroach chymotrypsin showed 32.7 to 43.1% identity with mite group 3 (trypsin) and group 6 (chymotrypsin) allergens. Sera from 8 of 28 German cockroach allergy subjects (28.6%) showed IgE binding to the recombinant protein. IgE binding to the recombinant cockroach chymotrypsin was inhibited by house dust mite chymotrypsin Der f 6, while it minimally inhibited the German cockroach whole body extract. A novel allergen homologous to chymotrypsin was identified from the German cockroach and was cross-reactive with Der f 6.

  10. DISTRIBUTION OF ALLERGENIC PLANTS IN RUSSIA

    Directory of Open Access Journals (Sweden)

    Tatiana V. Dikareva

    2015-01-01

    Full Text Available We analyzed, for the first time ever, the geographical distribution of the main allergenic plants in Russia. All materials were organized as database and attached to the map in GIS Mapinfo. For each region of Russian Federation, two indices were calculated: the total number of allergenic plants in the region and the “allergenic index”. A series of maps wascompiled: the number of spring-flowering species, the number of summer-flowering species,the total number of species flowering during the whole year, the overall allergen danger during spring and summer seasons, respectively, and the overall allergen danger during the whole year. In terms of the number of allergenic species and by the “allergenic index,” the most dangerous regions appeared to be the Ryazan and Voronezh Oblasts, while the less dangerous – the Chukotka Autonomous Okrug, and the Magadan Oblast. The maps may serve as a reference source for allergologists and allergy sufferers.

  11. Insect (food) allergy and allergens.

    Science.gov (United States)

    de Gier, Steffie; Verhoeckx, Kitty

    2018-05-03

    Insects represent an alternative for meat and fish in satisfying the increasing demand for sustainable sources of nutrition. Approximately two billion people globally consume insects. They are particularly popular in Asia, Latin America, and Africa. Most research on insect allergy has focussed on occupational or inhalation allergy. Research on insect food safety, including allergenicity, is therefore of great importance. The objective of this review is to provide an overview of cases reporting allergy following insect ingestion, studies on food allergy to insects, proteins involved in insect allergy including cross-reactive proteins, and the possibility to alter the allergenic potential of insects by food processing and digestion. Food allergy to insects has been described for silkworm, mealworm, caterpillars, Bruchus lentis, sago worm, locust, grasshopper, cicada, bee, Clanis bilineata, and the food additive carmine, which is derived from female Dactylopius coccus insects. For cockroaches, which are also edible insects, only studies on inhalation allergy have been described. Various insect allergens have been identified including tropomyosin and arginine kinase, which are both pan-allergens known for their cross-reactivity with homologous proteins in crustaceans and house dust mite. Cross-reactivity and/or co-sensitization of insect tropomyosin and arginine kinase has been demonstrated in house dust mite and seafood (e.g. prawn, shrimp) allergic patients. In addition, many other (allergenic) species (various non-edible insects, arachnids, mites, seafoods, mammals, nematoda, trematoda, plants, and fungi) have been identified with sequence alignment analysis to show potential cross-reactivity with allergens of edible insects. It was also shown that thermal processing and digestion did not eliminate insect protein allergenicity. Although purified natural allergens are scarce and yields are low, recombinant allergens from cockroach, silkworm, and Indian mealmoth are

  12. ZnS nanoflakes deposition by modified chemical method

    International Nuclear Information System (INIS)

    Desai, Mangesh A.; Sartale, S. D.

    2014-01-01

    We report deposition of zinc sulfide nanoflakes on glass substrates by modified chemical method. The modified chemical method involves adsorption of zinc–thiourea complex on the substrate and its dissociation in presence of hydroxide ions to release sulfur ions from thiourea which react with zinc ions present in the complex to form zinc sulfide nanoflakes at room temperature. Influence of zinc salt and thiourea concentrations ratios on the morphology of the films was investigated by scanning electron microscope (SEM). The ratio of zinc and thiourea in the zinc–thiourea complex significantly affect the size of the zinc sulfide nanoflakes, especially width and density of the nanoflakes. The X-ray diffraction analysis exhibits polycrystalline nature of the zinc sulfide nanoflakes with hexagonal phase

  13. ALLERGEN-SPECIFIC IMMUNOTHERAPY IN CHILDREN WITH POLLINOSIS

    Directory of Open Access Journals (Sweden)

    R. M. Torshkhoeva

    2014-01-01

    Full Text Available Aim: to compare clinical efficacy and safety of sublingual and parenteral allergen-specific immunotherapy in children with pollinosis. Patients and methods: 143 patients with pollinosis aged from 5 to 16 years old were included into the study. They were divided into 4 groups and received allergen-specific immunotherapy. Patients of the groups I and III were administered water-salt mixtures of extracts of tree pollen allergens. Patients from the II group received standardized adjuvant mixture of extracts of tree pollen allergens. Patients from the IV group were administered standardized extract of birch pollen allergens. Prophylaxis with water-salt solutions was performed before seasons of increased allergy risk during 3 years in autumns and winters. Prophylaxis with standardized extracts of allergens was performed uninterruptedly for 3 years. Results: allergen-specific immunotherapy prevents increase of sensitization and enlargement of allergen spectrum of elevated organism perceptibility, as well as prevents aggravation of disease course and conversion to more severe forms. It also decreases requirements of anti-allergic drugs and therefore elongates the duration of remission. Conclusions: allergen-specific immunotherapy with the use of standardized allergens is the most effective method of treatment of pollen sensitization in children. In order to increase its efficacy not less than 3 courses of immunotherapy are needed.

  14. Evaluation of the potential allergenicity of the enzyme microbial transglutaminase using the 2001 FAO/WHO Decision Tree

    DEFF Research Database (Denmark)

    Pedersen, Mona H.; Hansen, Tine K.; Sten, Eva

    2004-01-01

    All novel proteins must be assessed for their potential allergenicity before they are introduced into the food market. One method to achieve this is the 2001 FAO/WHO Decision Tree recommended for evaluation of proteins from genetically modified organisms (GMOs). It was the aim of this study...... to investigate the allergenicity of microbial transglutaminase (m-TG) from Streptoverticillium mobaraense. Amino acid sequence similarity to known allergens, pepsin resistance, and detection of protein binding to specific serum immunoglobulin E (IgE) (RAST) have been evaluated as recommended by the decision tree...... meets the requirements of the decision tree. However, there is a match at the five contiguous amino acid level to the major codfish allergen Gad c1. The potential cross reactivity between m-TG and Gad c1 was investigated in RAST using sera from 25 documented cod-allergic patients and an extract of raw...

  15. Allergens from fish and egg

    DEFF Research Database (Denmark)

    Poulsen, Lars K.; Hansen, T K; Nørgaard, A

    2001-01-01

    , denominated the parvalbumins. This cross-reactivity has been indicated to be of clinical relevance for several species, since patients with a positive double-blind, placebo-controlled food challenge to cod will also react with other fish species, such as herring, plaice and mackerel. In spite......Allergens from fish and egg belong to some of the most frequent causes of food allergic reactions reported in the literature. Egg allergens have been described in both white and yolk, and the egg white proteins ovomucoid, ovalbumin, ovotransferrin and lysozyme have been adopted in the allergen...... nomenclature as Gal d1-d4. The most reported allergen from egg yolk seems to be alpha-livitin. In fish, the dominating allergen is the homologues of Gad c1 from cod, formerly described as protein M. A close cross-reactivity exists within different species of fish between this calcium-binding protein family...

  16. Comparison of allergenicity and allergens between fish white and dark muscles.

    Science.gov (United States)

    Kobayashi, A; Tanaka, H; Hamada, Y; Ishizaki, S; Nagashima, Y; Shiomi, K

    2006-03-01

    Fish is one of the most frequent causes of immunoglobulin E (IgE)-mediated food allergy. Although the fish dark muscle is often ingested with the white muscle, no information about its allergenicity and allergens is available. Heated extracts were prepared from both white and dark muscles of five species of fish and examined for reactivity with IgE in fish-allergic patients by enzyme-linked immunosorbent assay (ELISA) and for allergens by immunoblotting. Cloning of cDNAs encoding parvalbumins was performed by rapid amplification cDNA ends. Parvalbumin contents in both white and dark muscles were determined by ELISA using antiserum against mackerel parvalbumin. Patient sera were less reactive to the heated extract from the dark muscle than to that from the white muscle. A prominent IgE-reactive protein of 12 kDa, which was detected in both white and dark muscles, was identified as parvalbumin. Molecular cloning experiments revealed that the same parvalbumin molecule is contained in both white and dark muscles of either horse mackerel or Pacific mackerel. Parvalbumin contents were four to eight times lower in the dark muscle than in the white muscle. The fish dark muscle is less allergenic than the white muscle, because the same allergen molecule (parvalbumin) is contained at much lower levels in the dark muscle than in the white muscle. Thus, the dark muscle is less implicated in fish allergy than the white muscle.

  17. Triethylene glycol bis(2-ethylhexanoate) - a new contact allergen identified in a spectacle frame

    DEFF Research Database (Denmark)

    Andersen, Klaus Ejner; Vestergaard, M. E.; Christensen, Lars Porskjær

    2014-01-01

    Background. Allergic reactions to spectacle frames are not unusual. A patient had a reproducible strong allergic patch test reaction to scrapings from the plastic material, and negative patch test results with available spectacle frame chemicals. Objectives. To identify the culprit allergen...... bis(2-ethylhexanoate) was the causative allergen in the spectacle frame. Ten consecutive eczema patients tested as controls were negative. Conclusion. Triethylene glycol bis(2-ethylhexanoate) is a new, hitherto unreported contact allergen....... in this patient's spectacle frame. Materials and methods. An extract from the temple arms was analysed by gas chromatography mass spectrometry (GC-MS), and a major low molecular weight compound was detected. This compound was isolated by semi-preparative high-performance liquid chromatography and identified by GC...

  18. Identification of novel allergen in edible insect, Gryllus bimaculatus and its cross-reactivity with Macrobrachium spp. allergens.

    Science.gov (United States)

    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.

  19. Multiple Chemical Sensitivity

    DEFF Research Database (Denmark)

    Dantoft, Thomas Meinertz

    Multiple chemical sensitivity (MCS) is a chronic disorder characterized by reports of symptoms from various organ systems attributed by the individuals to exposure to common odors and airborne chemicals in doses far below those known to induce toxic effects. There exists a general lack of knowledge......, significantly reduced levels of IL-13 in the MCS group and no group differences in the allergen specific IgE measures. The differences were independent of factors such as sex, age, Body Mass Index, asthma, smoking, depression, anxiety and allergen-specific IgE. In conclusion, the study identified a distinct...

  20. Encoded libraries of chemically modified peptides.

    Science.gov (United States)

    Heinis, Christian; Winter, Greg

    2015-06-01

    The use of powerful technologies for generating and screening DNA-encoded protein libraries has helped drive the development of proteins as pharmaceutical ligands. However the development of peptides as pharmaceutical ligands has been more limited. Although encoded peptide libraries are typically several orders of magnitude larger than classical chemical libraries, can be more readily screened, and can give rise to higher affinity ligands, their use as pharmaceutical ligands is limited by their intrinsic properties. Two of the intrinsic limitations include the rotational flexibility of the peptide backbone and the limited number (20) of natural amino acids. However these limitations can be overcome by use of chemical modification. For example, the libraries can be modified to introduce topological constraints such as cyclization linkers, or to introduce new chemical entities such as small molecule ligands, fluorophores and photo-switchable compounds. This article reviews the chemistry involved, the properties of the peptide ligands, and the new opportunities offered by chemical modification of DNA-encoded peptide libraries. Copyright © 2015. Published by Elsevier Ltd.

  1. Mechanisms of allergen-specific immunotherapy

    Directory of Open Access Journals (Sweden)

    Fujita Hiroyuki

    2012-01-01

    Full Text Available Abstract Allergen-specific immunotherapy (allergen-SIT is a potentially curative treatment approach in allergic diseases. It has been used for almost 100 years as a desensitizing therapy. The induction of peripheral T cell tolerance and promotion of the formation of regulatory T-cells are key mechanisms in allergen-SIT. Both FOXP3+CD4+CD25+ regulatory T (Treg cells and inducible IL-10- and TGF-β-producing type 1 Treg (Tr1 cells may prevent the development of allergic diseases and play a role in successful allergen-SIT and healthy immune response via several mechanisms. The mechanisms of suppression of different pro-inflammatory cells, such as eosinophils, mast cells and basophils and the development of allergen tolerance also directly or indirectly involves Treg cells. Furthermore, the formation of non-inflammatory antibodies particularly IgG4 is induced by IL-10. Knowledge of these molecular basis is crucial in the understanding the regulation of immune responses and their possible therapeutic targets in allergic diseases.

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

    NARCIS (Netherlands)

    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.

    2016-01-01

    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

  3. Simultaneous Determination of the Main Peanut Allergens in Foods Using Disposable Amperometric Magnetic Beads-Based Immunosensing Platforms

    Directory of Open Access Journals (Sweden)

    Víctor Ruiz-Valdepeñas Montiel

    2016-06-01

    Full Text Available In this work, a novel magnetic beads (MBs-based immunosensing approach for the rapid and simultaneous determination of the main peanut allergenic proteins (Ara h 1 and Ara h 2 is reported. It involves the use of sandwich-type immunoassays using selective capture and detector antibodies and carboxylic acid-modified magnetic beads (HOOC-MBs. Amperometric detection at −0.20 V was performed using dual screen-printed carbon electrodes (SPdCEs and the H2O2/hydroquinone (HQ system. This methodology exhibits high sensitivity and selectivity for the target proteins providing detection limits of 18.0 and 0.07 ng/mL for Ara h 1 and Ara h 2, respectively, with an assay time of only 2 h. The usefulness of the approach was evaluated by detecting the endogenous content of both allergenic proteins in different food extracts as well as trace amounts of peanut allergen (0.0001% or 1.0 mg/kg in wheat flour spiked samples. The developed platform provides better Low detection limits (LODs in shorter assay times than those claimed for the allergen specific commercial ELISA kits using the same immunoreagents and quantitative information on individual food allergen levels. Moreover, the flexibility of the methodology makes it readily translate to the detection of other food-allergens.

  4. Studies on allergoids from naturally occurring allergens. III. Preparation of ragweed pollen allergoids by aldehyde modification in two steps.

    Science.gov (United States)

    Marsh, D G; Norman, P S; Roebber, M; Lichtenstein, L M

    1981-12-01

    We have devised a new process for modifying heat-labile allergens, which employs a sequential "two-step" incubation at temperatures of 10 degree C and 30 degree to 32 degree C. This process was found to produce effective ragweed "allergoids" with low allergenicity and good immunogenicity, which makes them useful for the therapy of allergic humans. Modification with formaldehyde produced derivatives ("formallergoids") that were about 10-fold less allergenic in allergic humans (as measured by leukocyte histamine-release assay), and similarly or more immunogenic in guinea pigs, than glutaraldehyde-modified allergens ("glutarallergoids"). Further analysis by RAST inhibition showed that a ragweed formallergoid was sixfold less reactive than a glutarallergoid with a pool of human IgE antibodies. However, the formallergoid had retained the ability to induce a wide array of antibodies against native ragweed antigens, since rabbit anti-formallergoid serum was able to recognize at least 12 different ragweed antigens, including AgE. Gel-filtration experiments showed that both the formallergoid and glutarallergoid materials contained polymers having apparent molecular weights distributed around 260,000 and 230,000 daltons, respectively (approximate range 30,000 to 900,000 daltons). Our studies provide the immunochemical basis for the use of these allergoids in the therapy of allergic humans.

  5. Structural stability of Amandin, a major allergen from almond (Prunus dulcis), and its acidic and basic polypeptides.

    Science.gov (United States)

    Albillos, Silvia M; Menhart, Nicholas; Fu, Tong-Jen

    2009-06-10

    Information relating to the resistance of food allergens to thermal and/or chemical denaturation is critical if a reduction in protein allergenicity is to be achieved through food-processing means. This study examined the changes in the secondary structure of an almond allergen, amandin, and its acidic and basic polypeptides as a result of thermal and chemical denaturation. Amandin ( approximately 370 kDa) was purified by cryoprecipitation followed by gel filtration chromatography and subjected to thermal (13-96 degrees C) and chemical (urea and dithiothreitol) treatments. Changes in the secondary structure of the protein were followed using circular dichroism spectroscopy. The secondary structure of the hexameric amandin did not undergo remarkable changes at temperatures up to 90 degrees C, although protein aggregation was observed. In the presence of a reducing agent, irreversible denaturation occurred with the following experimental values: T(m) = 72.53 degrees C (transition temperature), DeltaH = 87.40 kcal/mol (unfolding enthalpy), and C(p) = 2.48 kcal/(mol degrees C) (heat capacity). The concentration of urea needed to achieve 50% denaturation was 2.59 M, and the Gibbs free energy of chemical denaturation was calculated to be DeltaG = 3.82 kcal/mol. The basic and acidic polypeptides of amandin had lower thermal stabilities than the multimeric protein.

  6. Sublingual allergen immunotherapy

    DEFF Research Database (Denmark)

    Calderón, M A; Simons, F E R; Malling, Hans-Jørgen

    2012-01-01

    To cite this article: Calderón MA, Simons FER, Malling H-J, Lockey RF, Moingeon P, Demoly P. Sublingual allergen immunotherapy: mode of action and its relationship with the safety profile. Allergy 2012; 67: 302-311. ABSTRACT: Allergen immunotherapy reorients inappropriate immune responses......-presenting cells (mostly Langerhans and myeloid dendritic cells) exhibit a tolerogenic phenotype, despite constant exposure to danger signals from food and microbes. This reduces the induction of pro-inflammatory immune responses leading to systemic allergic reactions. Oral tissues contain relatively few mast...... cells and eosinophils (mostly located in submucosal areas) and, in comparison with subcutaneous tissue, are less likely to give rise to anaphylactic reactions. SLIT-associated immune responses include the induction of circulating, allergen-specific Th1 and regulatory CD4+ T cells, leading to clinical...

  7. Biological resistance of polyethylene composites made with chemically modified fiber or flour

    Science.gov (United States)

    Rebecca E. Ibach; Craig M. Clemons

    2002-01-01

    The role of moisture in the biological decay of wood-plastic composites was investigated. Southern pine wood fiber and ponderosa pine wood flour were chemically modified using either acetic anhydride (AA), butylene oxide (BO), or propylene oxide (PO). A 50:50 mixture of high density polyethylene and either chemically modified fiber or flour, or untreated fiber or flour...

  8. Allergy immunotherapy with a hypoallergenic recombinant birch pollen allergen rBet v 1-FV in a randomized controlled trial.

    Science.gov (United States)

    Klimek, Ludger; Bachert, Claus; Lukat, Karl-Friedrich; Pfaar, Oliver; Meyer, Hanns; Narkus, Annemie

    2015-01-01

    Pollen extracts and chemically modified allergoids are used successfully in allergen immunotherapy (AIT). Recombinant extracts offer potential advantages with respect to pharmaceutical quality, standardization and dosing. A hypoallergenic recombinant folding variant of the major birch pollen allergen (rBet v 1-FV) was compared with an established native birch preparation. A pre-seasonal, randomized, actively controlled phase II study was performed in birch pollen allergic rhino-conjunctivitis with or without asthma, GINA I/ II. 51 patients (24 rBet v 1-FV, 27 native extract) started therapy with subcutaneous allergen immunotherapy (SCIT). Primary end-point was a combined symptom medication score (SMS), changes in nasal provocation test, visual rating score and specific antibody responses secondary end-points. After one pre-seasonal treatment course the combined SMS was 5.86 (median; IQR: 14.02) for the rBet v 1-FV group versus 12.40 (median; IQR: 9.32) for the comparator during the three weeks pollen season (p = 0.330). After treatment in the second year, scores were 3.00 (median; IQR: 6.50) and 2.93 (4.86) respectively. Allergen tolerance in a nasal provocation test improved to a comparable extent in both groups. Significant increases in birch pollen-specific IgG1 and IgG4 were observed in both treatment groups following the first treatment phase and remained significantly raised until the end of the study. In this first in man, proof of concept phase II trial no statistical difference between rBet v 1-FV and an established natural pollen extract could be observed. rBet v 1-FV could be administered in higher doses than the native protein with no increase in adverse effects. The study was registered in clinicalTrials.gov (NCT00266526).

  9. Public protection - reliable allergen risk management

    Science.gov (United States)

    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.

  10. Characterization and Assessment of Flavor Compounds and Some Allergens in Three Iranian Rice Cultivars during Gelatinization Process by HS-SPME/GC-MS

    Directory of Open Access Journals (Sweden)

    M. H. Givianrad

    2012-01-01

    Full Text Available A combined gas chromatography mass spectrometry with headspace solid-phase microextraction method has been utilized for the analysis of the flavor volatiles of three different rice cultivars including two modified Iranian rice cultivars and Hashemi rice cultivar during gelatinization. As a result, while gelatinization would progress, the amount of the volatile compounds would be also increased. Altogether, 74, 55 and 66 components were identified for Hashemi, HD5 and HD6 rice samples, respectively, which 56 unique compounds were not identified, previously. Subsequently, seven fragrance chemicals have been detected, which were most frequently reported as contact allergens in the European Union.

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

    Science.gov (United States)

    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.

  12. Reduction and alkylation of peanut allergen isoforms Ara h 2 and Ara h 6; characterization of intermediate- and end products.

    Science.gov (United States)

    Apostolovic, Danijela; Luykx, Dion; Warmenhoven, Hans; Verbart, Dennis; Stanic-Vucinic, Dragana; de Jong, Govardus A H; Velickovic, Tanja Cirkovic; Koppelman, Stef J

    2013-12-01

    Conglutins, the major peanut allergens, Ara h 2 and Ara h 6, are highly structured proteins stabilized by multiple disulfide bridges and are stable towards heat-denaturation and digestion. We sought a way to reduce their potent allergenicity in view of the development of immunotherapy for peanut allergy. Isoforms of conglutin were purified, reduced with dithiothreitol and subsequently alkylated with iodoacetamide. The effect of this modification was assessed on protein folding and IgE-binding. We found that all disulfide bridges were reduced and alkylated. As a result, the secondary structure lost α-helix and gained some β-structure content, and the tertiary structure stability was reduced. On a functional level, the modification led to a strongly decreased IgE-binding. Using conditions for limited reduction and alkylation, partially reduced and alkylated proteins were found with rearranged disulfide bridges and, in some cases, intermolecular cross-links were found. Peptide mass finger printing was applied to control progress of the modification reaction and to map novel disulfide bonds. There was no preference for the order in which disulfides were reduced, and disulfide rearrangement occurred in a non-specific way. Only minor differences in kinetics of reduction and alkylation were found between the different conglutin isoforms. We conclude that the peanut conglutins Ara h 2 and Ara h 6 can be chemically modified by reduction and alkylation, such that they substantially unfold and that their allergenic potency decreases. © 2013.

  13. Household Arthropod Allergens in Korea

    Science.gov (United States)

    Jeong, Kyoung Yong

    2009-01-01

    Arthropods are important in human health, which can transmit pathogens to humans, parasitize, or produce important allergens. Allergy prevalence becomes higher in Korea recently as well as other developed countries in contrast to a decrease of infectious diseases. Allergic diseases caused by household arthropods have increased dramatically during the last few decades since human beings spend more their time for indoor activities in modernized life style. Household arthropods are one of the most common causes of allergic diseases. Biological characterization of household arthropods and researches on their allergens will provide better understanding of the pathogenesis of allergic diseases and suggest new therapeutic ways. Therefore, studies on arthropods of allergenic importance can be considered one of the major research areas in medical arthropodology and parasitology. Here, the biology of several household arthropods, including house dust mites and cockroaches, the 2 most well known arthropods living indoor together with humans worldwide, and characteristics of their allergens, especially the research activities on these allergens performed in Korea, are summarized. PMID:19885330

  14. AllerML: markup language for allergens.

    Science.gov (United States)

    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.

  15. Chemical sensors based on molecularly modified metallic nanoparticles

    International Nuclear Information System (INIS)

    Haick, Hossam

    2007-01-01

    This paper presents a concise, although admittedly non-exhaustive, didactic review of some of the main concepts and approaches related to the use of molecularly modified metal nanoparticles in or as chemical sensors. This paper attempts to pull together different views and terminologies used in sensors based on molecularly modified metal nanoparticles, including those established upon electrochemical, optical, surface Plasmon resonance, piezoelectric and electrical transduction approaches. Finally, this paper discusses briefly the main advantages and disadvantages of each of the presented class of sensors. (review article)

  16. Nanoparticle–allergen complexes for allergen immunotherapy

    Directory of Open Access Journals (Sweden)

    Di Felice G

    2017-06-01

    Full Text Available Gabriella Di Felice,1 Paolo Colombo2 1National Center for Drug Research and Evaluation, Istituto Superiore di Sanità, Rome, 2Institute of Biomedicine and Molecular Immunology, National Research Council, Palermo, Italy Abstract: Allergen-specific immunotherapy was introduced in clinical settings more than 100 years ago. It remains the only curative approach to treating allergic disorders that ameliorates symptoms, reduces medication costs, and blocks the onset of new sensitizations. Despite this clinical evidence and knowledge of some immunological mechanisms, there remain some open questions regarding the safety and efficacy of this treatment. This suggests the need for novel therapeutic approaches that attempt to reduce the dose and frequency of treatment administration, improving patient compliance, and reducing costs. In this context, the use of novel adjuvants has been proposed and, in recent years, biomedical applications using nanoparticles have been exploited in the attempt to find formulations with improved stability, bioavailability, favorable biodistribution profiles, and the capability of targeting specific cell populations. In this article, we review some of the most relevant regulatory aspects and challenges concerning nanoparticle-based formulations with immunomodulatory potential, their related immunosafety issues, and the nature of the nanoparticles most widely employed in the allergy field. Furthermore, we report in vitro and in vivo data published using allergen/nanoparticle systems, discuss their impact on the immune system in terms of immunomodulatory activity and the reduction of side effects, and show that this strategy is a novel and promising tool for the development of allergy vaccines. Keywords: allergy, nanocarriers, immunotoxicity, immune modulation, immunotherapy, allergens

  17. Detection of allergen composition and in vivo immunogenicity of depigmented allergoids of Betula alba.

    Science.gov (United States)

    Carnés, J; Himly, M; Gallego, M; Iraola, V; Robinson, D S; Fernández-Caldas, E; Briza, P

    2009-03-01

    Chemical modification of allergen vaccines to reduce IgE binding improves safety while maintaining clinical efficacy. However, this also complicates the characterization of allergoids using techniques as for native allergen extracts. The objective of this study was to analyse the molecular size of Betula alba depigmented allergoids, conservation of major allergens in the allergoids and in vivo antibody response to immunization. The molecular size of depigmented allergoids was evaluated by high performance-size exclusion chromatography and light scattering techniques. Protein composition was compared with native extracts by capillary liquid chromatography-tandem mass spectrometry based peptide mapping. Rabbits were immunized with depigmented allergoid of Betula pollen adsorbed onto aluminium hydroxide (Depigoid). IgG antibodies against individual allergens were determined by ELISA and immunoblot. Depigmented allergoids contained a range of high molecular weight particles, approximately 60% of which had a molecular weight of 1-3 MDa. Peptide sequencing confirmed the preservation of five isoforms of Bet v 1, as well as Bet v 2, Bet v 6 and Bet v 7. Sera from immunized rabbits showed high levels of specific IgG to rBet v 1.0101 and rBet v 2. The mean protein content was 544+/-106 microg per mg of freeze-dried material for depigmented allergoids and 434+/-71 for native extracts. They retain the capacity to induce specific IgG antibodies against individual allergens present in the native extract. These findings confirm the immunogenicity of depigmented allergoids and may explain why patients treated with these vaccines are protected against the native allergens. Analysis of molecular size and allergen content may be useful techniques for characterization and standardization of allergoid products.

  18. Consumer preferences for food allergen labeling.

    Science.gov (United States)

    Marra, Carlo A; Harvard, Stephanie; Grubisic, Maja; Galo, Jessica; Clarke, Ann; Elliott, Susan; Lynd, Larry D

    2017-01-01

    Food allergen labeling is an important tool to reduce risk of exposure and prevent anaphylaxis for individuals with food allergies. Health Canada released a Canadian food allergen labeling regulation (2008) and subsequent update (2012) suggesting that research is needed to guide further iterations of the regulation to improve food allergen labeling and reduce risk of exposure. The primary objective of this study was to examine consumer preferences in food labeling for allergy avoidance and anaphylaxis prevention. A secondary objective was to identify whether different subgroups within the consumer population emerged. A discrete choice experiment using a fractional factorial design divided into ten different versions with 18 choice-sets per version was developed to examine consumer preferences for different attributes of food labeling. Three distinct subgroups of Canadian consumers with different allergen considerations and food allergen labeling needs were identified. Overall, preferences for standardized precautionary and safety symbols at little or no increased cost emerged. While three distinct groups with different preferences were identified, in general the results revealed that the current Canadian food allergen labeling regulation can be improved by enforcing the use of standardized precautionary and safety symbols and educating the public on the use of these symbols.

  19. Characterization of Cannabis sativa allergens.

    Science.gov (United States)

    Nayak, Ajay P; Green, Brett J; Sussman, Gordon; Berlin, Noam; Lata, Hemant; Chandra, Suman; ElSohly, Mahmoud A; Hettick, Justin M; Beezhold, Donald H

    2013-07-01

    Allergic sensitization to Cannabis sativa is rarely reported, but the increasing consumption of marijuana has resulted in an increase in the number of individuals who become sensitized. To date, little is known about the causal allergens associated with C sativa. To characterize marijuana allergens in different components of the C sativa plant using serum IgE from marijuana sensitized patients. Serum samples from 23 patients with a positive skin prick test result to a crude C sativa extract were evaluated. IgE reactivity was variable between patients and C sativa extracts. IgE reactivity to C sativa proteins in Western blots was heterogeneous and ranged from 10 to 70 kDa. Putative allergens derived from 2-dimensional gels were identified. Prominent IgE reactive bands included a 23-kDa oxygen-evolving enhancer protein 2 and a 50-kDa protein identified to be the photosynthetic enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase. Additional proteins were identified in the proteomic analysis, including those from adenosine triphosphate synthase, glyceraldehyde-3-phosphate dehydrogenase, phosphoglycerate kinase, and luminal binding protein (heat shock protein 70), suggesting these proteins are potential allergens. Deglycosylation studies helped refine protein allergen identification and demonstrated significant IgE antibodies against plant oligosaccharides that could help explain cross-reactivity. Identification and characterization of allergens from C sativa may be helpful in further understanding allergic sensitization to this plant species. Copyright © 2013 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  20. Avoidance Behavior against Positive Allergens Detected with a Multiple Allergen Simultaneous Test Immunoblot Assay in Patients with Urticaria: Factors Associated with Avoidance Success/Failure.

    Science.gov (United States)

    Lee, Min Kyung; Kwon, In Ho; Kim, Han Su; Kim, Heung Yeol; Cho, Eun Byul; Bae, Youin; Park, Gyeong Hun; Park, Eun Joo; Kim, Kwang Ho; Kim, Kwang Joong

    2016-02-01

    Avoidance behavior against positive allergens detected by using multiple allergen simultaneous test (MAST)-immunoblot assay in patients with urticaria has been rarely reported. We aimed to assess the avoidance behavior of patients with urticaria against positive allergens detected with a MAST. One hundred and one urticaria patients who showed positivity to at least one allergen on a MAST completed a questionnaire regarding their test results. The avoidance behavior of the patients was evaluated, and relevant determining factors of avoidance success/failure were statistically assessed. We detected 144 different data (n=51, food allergens; n=17, pollen allergens; and n=76, aeroallergens) from 101 patients with urticaria. The avoidance failure rates were 33.3% for food allergens, 70.6% for pollen allergens, and 30.3% for aeroallergens. The pollen group showed a significantly higher avoidance failure rate than the food and aeroallergen groups (psuccessfully avoid allergens (psuccess or failure against allergens in patients with urticaria when clinicians conduct allergen-specific immunoglobulin E tests.

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

    Science.gov (United States)

    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.

  2. Animal Allergens and Their Presence in the Environment

    Science.gov (United States)

    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

  3. Animal allergens and their presence in the environment

    Directory of Open Access Journals (Sweden)

    Eva eZahradnik

    2014-03-01

    Full Text Available 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.

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

    Science.gov (United States)

    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.

  5. Nasal mucosal blood flow after intranasal allergen challenge

    International Nuclear Information System (INIS)

    Holmberg, K.; Bake, B.; Pipkorn, U.

    1988-01-01

    The nasal mucosal blood flow in patients with allergic rhinitis was determined at nasal allergen challenges with the 133 Xenon washout method. Determinations were made in 12 subjects before and 15 minutes after challenge with diluent and increasing doses of allergen. The time course was followed in eight subjects by means of repeated measurements during 1 hour after a single allergen dose. Finally, the blood flow was measured after unilateral allergen challenge in the contralateral nasal cavity. A dose-dependent decrease in blood flow was found after nasal challenge with increasing doses of allergens, whereas challenge with diluent alone did not induce any changes. The highest allergen dose, which also induced pronounced nasal symptoms, resulted in a decrease in blood flow of 25% (p less than 0.001). The time-course study demonstrated a maximum decrease in blood flow 10 to 20 minutes after challenge and then a gradual return to baseline. Unilateral allergen challenge resulted in a decrease in blood flow in the contralateral, unchallenged nasal cavity, suggesting that part of the allergen-induced changes in blood flow were reflex mediated

  6. Modulation of the allergen-induced human IgE response in Hu-SCID mice: inhibitory effect of human recombinant IFN-gamma and allergen-derived lipopeptide.

    Science.gov (United States)

    Duez, C; Gras-Masse, H; Hammad, H; Akoum, H; Didierlaurent, A; André, C; Tonnel, A B; Pestel, J

    2001-01-01

    We have previously established a model to study the in vivo human IgE response using humanized SCID mice. Allergic SCID mice were obtained following intraperitoneal injection with mononuclear cells from Dermatophagoides pteronyssinus (Dpt)-sensitive patients, and sensitization by Dpt allergen intraperitoneal injection (immunization) or Dpt aerosol (inhalation). Human serum IgE was measured in allergic SCID mice after administration of human recombinant IFN-gamma or the lipopeptide LP 52-71 (derived from peptide p52-71 from Der p 1, Dpt major allergen, coupled to a lipophilic moiety), during the immunization or the inhalation phase. IFN-gamma inhibited human IgE production when given at the time of immunization, but not during inhalation. This effect was long-lasting as Dpt aerosol, given one month after immunization and IFN-gamma administration, failed to increase IgE levels. Unlike Dpt or p52-71, LP 52-71 failed to induce human IgE production at day 14 and 21 after its injection, but did inhibit the development of the IgE response after a secondary Dpt-challenge. Moreover, LP 52-71 administration 14 days after Dpt inhalation decreased IgE levels, in contrast to peptide 52-71, which increased IgE levels. Thus, taken together these results indicate that the development of the human IgE response in allergic SCID mice can be modulated by modified allergen and a Th1 cytokine.

  7. HYMENOPTERA ALLERGENS: FROM VENOM TO VENOME

    Directory of Open Access Journals (Sweden)

    Edzard eSpillner

    2014-02-01

    Full Text Available In Western Europe hymenoptera venom allergy primarily relates to venoms of the honeybee and the common yellow jacket. In contrast to other allergen sources, only a few major components of hymenoptera venoms had been characterized until recently. Improved expression systems and proteomic detection strategies have allowed the identification and characterization of a wide range of additional allergens. The field of hymenoptera venom allergy research has moved rapidly from focusing on venom extract and single major allergens to a molecular understanding of the entire venome as a system of unique and characteristic components. An increasing number of such components has been identified, characterized regarding function and assessed for allergenic potential. Moreover, advanced expression strategies for recombinant production of venom allergens allow selective modification of molecules and provide insight into different types of IgE reactivities and sensitization patterns. The obtained information contributes to an increased diagnostic precision in hymenoptera venom allergy and may serve for monitoring, reevaluation and improvement of current therapeutic strategies.

  8. Food, novel foods, and allergenicity

    NARCIS (Netherlands)

    Loveren H van; LPI

    2002-01-01

    Certain foods lead may to allergic responses in certain individuals. Main allergenic foods are Crustacea (shrimp, lobster, crab), egg, fish, milk, peanuts, soybeans, tree nuts, and wheat, and allergens are always proteins. A wide array of symptoms can result from food allergy (gastrointestinal,

  9. Distribution of peanut allergen in the environment.

    Science.gov (United States)

    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.

  10. The human allergens of mesquite (Prosopis juliflora).

    Science.gov (United States)

    Killian, Sue; McMichael, John

    2004-07-05

    BACKGROUND: A computerized statistical analysis of allergy skin test results correlating patient reactivities initiated our interest in the cross-reactive allergens of mesquite tree pollen. In-vitro testing with mesquite-sensitized rabbits and a variety of deciduous tree pollens revealed so many cross-reactivities that it became apparent there could be more allergens in mesquite than previously described in the world literature. Our purpose was to examine the allergens of mesquite tree pollen (Prosopis juliflora) which elicit an IgE response in allergic humans so that future research could determine if these human allergens cross-react with various tree pollens in the same manner as did the mesquite antiserum from sensitized rabbits. METHODS: Proteins from commercial mesquite tree pollen were separated by polyacrylamide gel electrophoresis in the presence of sodium-dodecyl-sulphate. These mesquite proteins were subjected to Western blotting using pooled sera from ten mesquite-sensitive patients and goat anti-human IgE. The allergens were detected using an Amplified Opti-4-CN kit, scanned, and then interpreted by Gel-Pro software. RESULTS: Thirteen human allergens of mesquite pollen were detected in this study. CONCLUSION: The number of allergens in this study of mesquite exceeded the number identified previously in the literature. With the increased exposure to mesquite through its use in "greening the desert", increased travel to desert areas and exposure to mesquite in cooking smoke, the possible clinical significance of these allergens and their suggested cross-reactivity with other tree pollens merit further study.

  11. Identification of Maillard reaction induced chemical modifications on Ara h 1

    Science.gov (United States)

    The Maillard reaction is a non-enzymatic glycation reaction between proteins and reducing sugars that can modify nut allergens during thermal processing. These modifications can alter the structural and immunological properties of these allergens, and may result in increased IgE binding. Here, we ...

  12. Probing Chromatin-modifying Enzymes with Chemical Tools

    KAUST Repository

    Fischle, Wolfgang

    2016-02-04

    Chromatin is the universal template of genetic information in all eukaryotic organisms. Chemical modifications of the DNA-packaging histone proteins and the DNA bases are crucial signaling events in directing the use and readout of eukaryotic genomes. The enzymes that install and remove these chromatin modifications as well as the proteins that bind these marks govern information that goes beyond the sequence of DNA. Therefore, these so-called epigenetic regulators are intensively studied and represent promising drug targets in modern medicine. We summarize and discuss recent advances in the field of chemical biology that have provided chromatin research with sophisticated tools for investigating the composition, activity, and target sites of chromatin modifying enzymes and reader proteins.

  13. 21 CFR 680.1 - Allergenic Products.

    Science.gov (United States)

    2010-04-01

    ... ADDITIONAL STANDARDS FOR MISCELLANEOUS PRODUCTS § 680.1 Allergenic Products. (a) Definition. Allergenic Products are products that are administered to man for the diagnosis, prevention or treatment of allergies...

  14. Comparison of international food allergen labeling regulations.

    Science.gov (United States)

    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.

  15. Chemically modified carbon fibers and their applications

    International Nuclear Information System (INIS)

    Ermolenko, I.N.; Lyubliner, I.P.; Gulko, N.V.

    1990-01-01

    This book gives a comprehensive review about chemically modified carbon fibers (e.g. by incorporation of other elements) and is structured as follows: 1. Types of carbon fibers, 2. Structure of carbon fibers, 3. Properties of carbon fibers, 4. The cellulose carbonization process, 5. Formation of element-carbon fiber materials, 6. Surface modification of carbon fibers, and 7. Applications of carbon fibers (e.g. adsorbents, catalysts, constituents of composites). (MM)

  16. Associations between baseline allergens and polysensitization

    DEFF Research Database (Denmark)

    Carlsen, B.C.; Menne, T.; Johansen, J.D.

    2008-01-01

    Background: Identification of patients at risk of developing polysensitization is not possible at present. An association between weak sensitizers and polysensitization has been hypothesized. Objectives: To examine associations of 21 allergens in the European baseline series to polysensitization....... Patients/Methods: From a database-based study with 14 998 patients patch tested with the European baseline series between 1985 and 2005, a group of 759 (5.1%) patients were polysensitized. Odds ratios were calculated to determine the relative contribution of each allergen to polysensitization. Results...... denominator for the association between the allergens and the polysensitization was apparent, and any association, whether positive or negative, was relatively low. Based on these results, sensitization to specific baseline allergens cannot be used as risk indicators for polysensitization Udgivelsesdato: 2008...

  17. Associations between baseline allergens and polysensitization

    DEFF Research Database (Denmark)

    Carlsen, Berit Christina; Menné, Torkil; Johansen, Jeanne Duus

    2008-01-01

    BACKGROUND: Identification of patients at risk of developing polysensitization is not possible at present. An association between weak sensitizers and polysensitization has been hypothesized. OBJECTIVES: To examine associations of 21 allergens in the European baseline series to polysensitization....... PATIENTS/METHODS: From a database-based study with 14 998 patients patch tested with the European baseline series between 1985 and 2005, a group of 759 (5.1%) patients were polysensitized. Odds ratios were calculated to determine the relative contribution of each allergen to polysensitization. RESULTS...... denominator for the association between the allergens and the polysensitization was apparent, and any association, whether positive or negative, was relatively low. Based on these results, sensitization to specific baseline allergens cannot be used as risk indicators for polysensitization....

  18. Food allergens and mucosal immune systems with special reference to recognition of food allergens by gut-associated lymphoid tissue

    Directory of Open Access Journals (Sweden)

    Shuichi Kaminogawa

    1999-01-01

    Full Text Available Food allergy, triggered by an aberrant immune response elicited by orally ingested food allergens, is generated through a complicated mechanism because the allergen interacts with the mucosal immune system (the gut- associated lymphoid tissue, GALT and the resulting immune response affects the generation of allergy. This review will describe the process by which antigens or allergens are recognized by the GALT and the characteristic immune responses induced thereafter. Orally administered antigens induce distinct immune responses in the Peyer's patches, lamina propria and the intestinal epithelium. In addition to these local immune responses in the gut, ingested antigens are known to affect systemic immunity. These may induce a suppressed state of systemic immune responsiveness, which is called oral tolerance, or in some cases they may elicit a systemic IgE antibody response which may lead to allergic reactions. Information on the regions on food allergens recognized by T cells and IgE antibodies is important in understanding the fates of food allergens after being recognized by the GALT. The structure of T and B cell epitopes on food allergens and the possibility of modulation of allergic reactions by amino-acid substituted analogs of allergen- derived peptides will also be discussed.

  19. Identification of autoclave-resistant Anisakis simplex allergens.

    Science.gov (United States)

    Carballeda-Sangiao, Noelia; Olivares, Fabiola; Rodriguez-Mahillo, Ana I; Careche, Mercedes; Tejada, Margarita; Moneo, Ignacio; González-Muñoz, Miguel

    2014-04-01

    Anisakis simplex is a fish parasite able to induce allergic reactions in humans infected when eating raw or undercooked fish parasitized with viable third-stage larvae. Some authors claim that exposure to nonviable Anisakis material can result in allergic symptoms in previously sensitized patients, indicating that parasite allergens are resistant to the thermal treatments of usual cooking procedures. Furthermore, some patients report symptoms after eating canned fish. The aim of this work was the analysis of parasite allergen stability in heating to 121 °C in an autoclave to simulate the thermal process applied to canned fish. Third-stage larvae were subjected to autoclaving for 20, 40, and 80 min, and parasite crude extracts were analyzed by electrophoresis, immunoblotting, and a flow-cytometric basophil activation test. Allergens resistant to autoclaving were separated by reversed-phase high-performance liquid chromatography and identified by ion trap mass spectrometry. Protein analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that autoclaving considerably reduced the number and intensity of identifiable protein bands in a time-dependent manner. Several allergens were detected by immunoblotting with a pool of A. simplex allergic patients' sera after autoclaving. Allergens of 9 and 14 kDa resistant to autoclaving were identified as Ani s 4 and Ani s 1 allergens, respectively. Functional analysis showed that allergens retain their capacity to activate basophils even after autoclaving for 80 min. In conclusion, some relevant A. simplex allergens retain their capacity to bind immunoglobulin E and activate basophils after being subjected to autoclaving, which is a method equivalent to that used in industrial canning processes.

  20. The human allergens of mesquite (Prosopis juliflora

    Directory of Open Access Journals (Sweden)

    Killian Sue

    2004-07-01

    Full Text Available Abstract Background A computerized statistical analysis of allergy skin test results correlating patient reactivities initiated our interest in the cross-reactive allergens of mesquite tree pollen. In-vitro testing with mesquite-sensitized rabbits and a variety of deciduous tree pollens revealed so many cross-reactivities that it became apparent there could be more allergens in mesquite than previously described in the world literature. Our purpose was to examine the allergens of mesquite tree pollen (Prosopis juliflora which elicit an IgE response in allergic humans so that future research could determine if these human allergens cross-react with various tree pollens in the same manner as did the mesquite antiserum from sensitized rabbits. Methods Proteins from commercial mesquite tree pollen were separated by polyacrylamide gel electrophoresis in the presence of sodium-dodecyl-sulphate. These mesquite proteins were subjected to Western blotting using pooled sera from ten mesquite-sensitive patients and goat anti-human IgE. The allergens were detected using an Amplified Opti-4-CN kit, scanned, and then interpreted by Gel-Pro software. Results Thirteen human allergens of mesquite pollen were detected in this study. Conclusion The number of allergens in this study of mesquite exceeded the number identified previously in the literature. With the increased exposure to mesquite through its use in "greening the desert", increased travel to desert areas and exposure to mesquite in cooking smoke, the possible clinical significance of these allergens and their suggested cross-reactivity with other tree pollens merit further study.

  1. Lol p XI, a new major grass pollen allergen, is a member of a family of soybean trypsin inhibitor-related proteins.

    Science.gov (United States)

    van Ree, R; Hoffman, D R; van Dijk, W; Brodard, V; Mahieu, K; Koeleman, C A; Grande, M; van Leeuwen, W A; Aalberse, R C

    1995-05-01

    Monoclonal antibodies were obtained against an unknown allergen from Lolium perenne grass pollen. The allergen had an apparent molecular mass of 18 kd on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Earlier immunoblotting studies had shown that carbohydrate-specific IgG antibodies recognize an antigen of similar size. We sought to characterize the allergen biochemically and immunologically. The amino acid sequence of the allergen was determined by automated Edman degradation, and its monosaccharide composition was determined by gas chromatographic analysis. A panel of 270 grass pollen-positive sera was assessed in a RAST with the purified allergen. Protease digestion (proteinase K) and chemical deglycosylation (trifluoromethane sulfonic acid) were used to distinguish between carbohydrate and peptide epitopes for IgE antibodies. The allergen was shown to be a glycoprotein with a molecular mass of 16 kd, of which 8% is carbohydrate. Its amino acid sequence shares 32% homology with soybean trypsin inhibitor (Kunitz) but lacks its active site. No homology was found with known grass pollen allergens, hence it was designated Lol p XI. A high degree of homology (44%) was found with a tree pollen allergen, Ole e I, the major allergen of olive pollen. More than 65% of grass pollen-positive sera had IgE against Lol p XI. IgE reactivity was demonstrated both with the carbohydrate moiety and the peptide backbone. Lol p XI is a new major grass pollen allergen carrying an IgE-binding carbohydrate determinant. Lol p XI is structurally related to the major allergen from olive pollen.

  2. Allergens labeling on French processed foods - an Oqali study.

    Science.gov (United States)

    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.

  3. Studies on `allergoids' prepared from naturally occurring allergens

    Science.gov (United States)

    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

  4. Levels of house dust mite allergen in cars.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  6. The hazard communication of fragrance allergens must be improved.

    Science.gov (United States)

    Klaschka, Ursula

    2013-07-01

    Contact allergy is a global health problem that could be alleviated considerably if the general public could reduce contact to sensitizers. Efficient hazard communication would be a valuable instrument to achieve this. What do current regulations concerning fragrance sensitizers in cosmetic products in Europe contribute? For example, there are bans and restrictions according to the Cosmetic Regulation, there is the "26 allergens rule" that requires that the names of some allergenic fragrance ingredients are listed on the containers, there is labeling and classification of hazardous products according to Regulation 1272/2008, and there is the regulation concerning the registration, evaluation, authorization and restriction of chemicals (REACH). Do these regulations increase consumer protection by suitable hazard communication instruments? Four main problems were identified. First, according to the 26 allergens rule, consumers carry a very large part of the responsibility for risk reduction management. They need to be capable and motivated to recognize the names of strong allergens listed in the ingredient list and decide for themselves whether they want to run the risk or not, provided that they are aware of their responsibility. Second, cosmetic products do not need to be classified and labeled like other consumer goods, according to the European Commission Regulation 1272/2008, if they contain hazardous substances. Third, some pictograms for hazardous substances, for example, the exclamation mark for sensitizers, are not well understood by the majority of the general public. Fourth, very often, the design of cosmetic containers implies health and well being, even if the respective products contain sensitizers or other hazardous substances. Against this background, the following improvements are proposed: 1) the 26 allergens rule needs revision, 2) the exception for cosmetic products from labeling and classification should be abolished, 3) a new self

  7. Supersensitive fingerprinting of explosives by chemically modified nanosensors arrays

    Science.gov (United States)

    Lichtenstein, Amir; Havivi, Ehud; Shacham, Ronen; Hahamy, Ehud; Leibovich, Ronit; Pevzner, Alexander; Krivitsky, Vadim; Davivi, Guy; Presman, Igor; Elnathan, Roey; Engel, Yoni; Flaxer, Eli; Patolsky, Fernando

    2014-06-01

    The capability to detect traces of explosives sensitively, selectively and rapidly could be of great benefit for applications relating to civilian national security and military needs. Here, we show that, when chemically modified in a multiplexed mode, nanoelectrical devices arrays enable the supersensitive discriminative detection of explosive species. The fingerprinting of explosives is achieved by pattern recognizing the inherent kinetics, and thermodynamics, of interaction between the chemically modified nanosensors array and the molecular analytes under test. This platform allows for the rapid detection of explosives, from air collected samples, down to the parts-per-quadrillion concentration range, and represents the first nanotechnology-inspired demonstration on the selective supersensitive detection of explosives, including the nitro- and peroxide-derivatives, on a single electronic platform. Furthermore, the ultrahigh sensitivity displayed by our platform may allow the remote detection of various explosives, a task unachieved by existing detection technologies.

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

    Science.gov (United States)

    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.

  9. Common Allergens Identified Based on Patch Test Results in Patients with Suspected Contact Dermatitis of the Scalp.

    Science.gov (United States)

    Aleid, Nouf M; Fertig, Raymond; Maddy, Austin; Tosti, Antonella

    2017-03-01

    Contact dermatitis of the scalp is common and might be caused by many chemicals including metals, ingredients of shampoos and conditioners, dyes, or other hair treatments. Eliciting a careful history and patch tests are necessary to identify the responsible allergen and prevent relapses. To identify allergens that may cause contact dermatitis of the scalp by reviewing patch test results. We reviewed the records of 1,015 patients referred for patch testing at the Dermatology Department of the University of Miami. A total of 226 patients (205 females and 21 males) with suspected scalp contact dermatitis were identified, and the patch test results and clinical data for those patients were analyzed. Most patients were referred for patch testing from a specialized hair clinic at our institution. The most common allergens in our study population were nickel (23.8%), cobalt (21.0%), balsam of Peru (18.2%), fragrance mix (14.4%), carba mix (11.6%), and propylene glycol (PG) (8.8%). The majority of patients were females aged 40-59 years, and scalp itching or burning were reported as the most common symptom. Frequent sources of allergens for metals include hair clasps, pins, and brushes, while frequent sources of allergens for preservatives, fragrance mix, and balsam of Peru include shampoos, conditioners, and hair gels. Frequent sources of allergens for PG include topical medications.

  10. Common Allergens Identified Based on Patch Test Results in Patients with Suspected Contact Dermatitis of the Scalp

    Science.gov (United States)

    Aleid, Nouf M.; Fertig, Raymond; Maddy, Austin; Tosti, Antonella

    2017-01-01

    Background Contact dermatitis of the scalp is common and might be caused by many chemicals including metals, ingredients of shampoos and conditioners, dyes, or other hair treatments. Eliciting a careful history and patch tests are necessary to identify the responsible allergen and prevent relapses. Objectives To identify allergens that may cause contact dermatitis of the scalp by reviewing patch test results. Methods We reviewed the records of 1,015 patients referred for patch testing at the Dermatology Department of the University of Miami. A total of 226 patients (205 females and 21 males) with suspected scalp contact dermatitis were identified, and the patch test results and clinical data for those patients were analyzed. Most patients were referred for patch testing from a specialized hair clinic at our institution. Results The most common allergens in our study population were nickel (23.8%), cobalt (21.0%), balsam of Peru (18.2%), fragrance mix (14.4%), carba mix (11.6%), and propylene glycol (PG) (8.8%). The majority of patients were females aged 40–59 years, and scalp itching or burning were reported as the most common symptom. Conclusion Frequent sources of allergens for metals include hair clasps, pins, and brushes, while frequent sources of allergens for preservatives, fragrance mix, and balsam of Peru include shampoos, conditioners, and hair gels. Frequent sources of allergens for PG include topical medications. PMID:28611994

  11. Lyral: a fragrance allergen.

    Science.gov (United States)

    Militello, Giuseppe; James, William

    2005-03-01

    Fragrances are a common cause of contact dermatitis and account for a large percentage of reactions to cosmetic products. Novel fragrance compounds that may not be detected by the common fragrance screening agents (including balsam of Peru and fragrance mix) are continually being produced. Lyral is one of those allergens found in many cosmetic and household products. This review will discuss the recent literature and the significance of this allergen to allergic contact dermatitis.

  12. The current state of recombinant allergens for immunotherapy

    DEFF Research Database (Denmark)

    Pauli, Gabrielle; Malling, H-J

    2010-01-01

    Subcutaneous immunotherapy is a well documented treatment of allergic rhinitis and asthma. The majority of the disadvantages of the treatment are related to the poor quality of the natural allergen extracts which can contain varying amounts of individual allergens including allergens to which...

  13. First successful reduction of clinical allergenicity of food by genetic modification: Mal d 1-silenced apples cause fewer allergy symptoms than the wild-type cultivar

    DEFF Research Database (Denmark)

    Dubois, A. E. J.; Pagliarani, G.; Brouwer, R. M.

    2015-01-01

    BACKGROUND: Genetic modification of allergenic foods such as apple has the potential to reduce their clinical allergenicity, but this has never been studied by oral challenges in allergic individuals. METHODS: We performed oral food challenges in 21 apple-allergic individuals with Elstar apples...... which had undergone gene silencing of the major allergen of apple, Mal d 1, by RNA interference. Downregulation of Mal d 1 gene expression in the apples was verified by qRT-PCR. Clinical responses to the genetically modified apples were compared to those seen with the wild-type Elstar using a visual...

  14. Effectiveness of allergen-specific immunotherapy with pollen allergens in children from the viewpoint of molecular allergology

    Directory of Open Access Journals (Sweden)

    S.M. Nedelska

    2017-03-01

    Full Text Available Background. Allergen-specific immunotherapy as elimination procedures is the only method of treatment and prevention of allergic disorders formation and exacerbation of clinical symptoms. One of the approaches to molecular diagnosis is choice of allergen for allergen-specific immunotherapy (ASIT. The purpose of our study was to identify possible reasons of failure of ASIT with pollen allergens (predominantly weeds in children with seasonal allergic rhinitis (hay fever and/or bronchial asthma based on studying hypersensitivity to the allergens, analysis of anamnestic data. Materials and methods. Allergy skin prick tests were conducted to 192 children (middle age 9.8 ± 2.7 years with the seasonal symptoms of rhinitis and/or bronchial asthma according to standard methodology with pollen allergens of Immunolog Ltd (Vinnytsia. We evaluated positive results as 5 mm and higher diameter of papula/hyperemia. The anamnestic survey was carried out in 52 patients by means of the questionnaire that contained questions about cross allergy (pollen-food, oral allergy syndrome, concomitant pathology of upper respiratory tract and effectiveness of АSІТ, which is elaborated by us. Results. The skin prick tests show that in 192 patients, who have hay fever, ragweed, sunflower sensibilization predominates (56 and 58 %, correspondingly. About 10–20 % of children are sensitive to cereals (ryegrass, fescue. To the allergens of poplar, acacia, couch-grass, oak, mint, nettle, walnut, the positive reactions of prick tests were observed in 3–7 children, that is 1.5–3.6 %. According to our results, 23 % of patients had sensibilization to 5 and more pollen allergens. 52 % of children had concomitant food allergy, 15 % of patients have reactions of the lips, oral cavity when using certain products, mostly tomatoes, nuts, seeds (they were diagnosed oral allergy syndrome. Also, one third of children have varying degrees of adenoid hypertrophy, tonsils hypertrophy

  15. Authentication of food allergen quality by physicochemical and immunological methods

    DEFF Research Database (Denmark)

    Sancho, A I; Hoffmann-Sommergruber, K; Alessandri, S

    2010-01-01

    Purified allergens are required to detect cross-contamination with other allergenic foods and to understand allergen interaction with other components of the food matrix. Pure allergens are also used for the diagnosis and treatment of food allergies. For example, serological methods are being...... developed to improve the quality of diagnosis, and to reduce the need for food challenge tests. In addition, recombinant allergens are being evaluated as candidate vaccines for safe and efficacious specific immunotherapy. Pure allergens are indispensable as reference materials for the calibration...... and standardization of methods between different laboratories and operators for risk assessment in the food industry. Therefore, there is a need for well-defined purified food allergens. In this context, a panel of 46 food allergens from plant and animal sources has been purified, from either the food sources...

  16. Effect of irradiation on biochemistry properties of shrimp allergen

    International Nuclear Information System (INIS)

    Gu Kefei; Gao Meixu; Li Chunhong; Li Shurong; Pan Jiarong

    2007-01-01

    Study on the effects of 60 Co γ-rays irradiation at the dose of 0,3,5,7,10 kGy on shrimp allergen biochemistry properties was conducted. The results indicated that the allergen protein molecule can be broken down to smaller molecules or coagulated to larger molecules by irradiation. The hydrophobicity and turbidity of irradiated allergen increased with the increase of absorbed dose. The results also show that allergen solution is more sensitive to irradiation than allergen in solid state or in the whole shrimp. (authors)

  17. Dust Allergens within Rural Northern Rocky Mountain Residences.

    Science.gov (United States)

    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.

  18. Allergenic Proteins in Foods and Beverages

    Directory of Open Access Journals (Sweden)

    Fernanda Cosme

    2013-01-01

    Full Text Available Food allergies can be defined as immunologically mediated hypersensitivity reactions; therefore, a food allergy is also known as food hypersensitivity. The reactions are caused by the immune system response to some food proteins. The eight most common food allergens are proteins from milk, eggs, peanuts, tree nuts, soya, wheat, fish and shellfish. However, many other foods have been identified as allergens for some people, such as certain fruits or vegetables and seeds. It is now recognized that food allergens are an important food safety issue. A food allergy occurs when the body’s immune system reacts to otherwise harmless substances in certain foods. For these reasons, one of the requirements from the European Union is that allergenic food ingredients should be labelled in order to protect allergic consumers. According to the European Federation of Allergy and Airways Diseases Patients’ Associations, about 8 % of children and 4 % of adults suffer from some type of food allergy. Food allergies often develop during infant or early childhood ages, affecting mainly the gastrointestinal tract (stomach and intestines. In some cases, the allergy may persist in adult age, for example, coeliac disease, which is an abnormal immune response to certain proteins present in gluten, a type of protein composite found in wheat and barley. Almost all allergens are proteins, and highly sensitive analytical methods have been developed to detect traces of these compounds in food, such as electrophoretic and immunological methods, enzyme-linked immunosorbent assay (ELISA and polyacrylamide gel electrophoresis. The purpose of this review is to describe the allergenic components of the most common causes of food allergies, followed by a brief discussion regarding their importance in the food industry and for consumer safety. The most important methods used to detect allergenicity in food will also be discussed.

  19. Common indoor and outdoor aero-allergens in South Africa

    African Journals Online (AJOL)

    Aero-allergens in South Africa that are also encountered around the world are listed in Table I. In addition to this wide range of common aero-allergens, South Africans are also exposed to a full range of food allergens, some of which, e.g. perlemoen (Haliotis midae) and other seafood allergens, are unique to this region.

  20. Hierarchy and molecular properties of house dust mite allergens

    Directory of Open Access Journals (Sweden)

    Wayne R. Thomas

    2015-10-01

    Full Text Available The allergenic load of house dust mite allergy is largely constituted by a few proteins with a hierarchical pattern of allergenicity. The serodominant specificities are the group 1&2 and the group 23 faecal allergens. The collective IgE binding to the group 1&2 allergens can measure unequivocal HDM sensitisation better than HDM extracts although discrepancies have been found in regions with complex acarofauna suggesting a need to investigate the specificity with allergen components. The group 4, 5, 7&21 allergens that each induce responses in about 40% of subjects are mid-tier allergens accounting for most of the remaining IgE binding. Their titres are proportional to the concomitant responses to Der p1&2. Group 2 allergen variants have different antibody binding. Body proteins only occasionally induce sensitisation although a higher prevalence of binding by atopic dermatitis patients provides a new avenue of research. A broad spectrum of IgE binding has been associated with diverse symptoms but not with the severity of asthma which is associated with low IgG antibody. Some allergens such as the group 14 large lipid binding proteins and the recently described proteins Der f 24–33, need further investigation but with the cognoscence that other denominated allergens have been found to be minor sensitisers by comparative quantitative analyses. Scabies is a confounder for diagnosis with extracts, inducing cross-reactive antibodies with Der p 4&20 as is seafood allergy with cross reactivity to Der p 10 a minor HDM allergen. The HDM genome sequence can now be used to verify allelic and paralogous variations.

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

    Science.gov (United States)

    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.

  2. Proteomic analysis of the major birch allergen Bet v 1 predicts allergenicity for 15 birch species

    NARCIS (Netherlands)

    Schenk, M.F.; Cordewener, J.H.G.; America, A.H.P.; Peters, J.; Smulders, M.J.M.; Gilissen, L.J.W.J.

    2011-01-01

    Pollen of the European and Asian white birch (Betula pendula and B. platyphylla) causes hay fever in humans. The allergenic potency of other birch species is largely unknown. To identify birch trees with a reduced allergenicity, we assessed the immunochemical characteristics of 15 species and two

  3. Novel approach for classifying chemicals according to skin sensitizing potency by non-radioisotopic modification of the local lymph node assay.

    Science.gov (United States)

    Takeyoshi, Masahiro; Iida, Kenji; Shiraishi, Keiji; Hoshuyama, Satsuki

    2005-01-01

    The murine local lymph node assay (LLNA) is currently recognized as a stand-alone sensitization test for determining the sensitizing potential of chemicals, and it has the advantage of yielding a quantitative endpoint that can be used to predict the sensitization potency of chemicals. The EC3 has been proposed as a parameter for classifying chemicals according to the sensitization potency. We previously developed a non-radioisotopic endpoint for the LLNA based on 5-bromo-2'-deoxyuridine (BrdU) incorporation (non-RI LLNA), and we are proposing a new procedure to predict the sensitization potency of chemicals based on comparisons with known human contact allergens. Nine chemicals (i.e. diphencyclopropenone, p-phenylenediamine, glutaraldehyde, cinnamicaldehyde, citral, eugenol, isopropyl myristate, propyleneglycol and hexane) categorized as human contact allergen classes 1-5 were tested by the non-RI LLNA with the following reference allergens: 2,4-dinitrochlorobenzene (DNCB) as a class 1 human contact allergen, isoeugenol as a class 2 human contact allergen and alpha-hexylcinnamic aldehyde (HCA) as a class 3 human contact allergen. Consequently, nine test chemicals were almost assigned to their correct allergen class. The results suggested that the new procedure for non-RI LLNA can provide correct sensitization potency data. Sensitization potency data are useful for evaluating the sensitization risk to humans of exposure to new chemical products. Accordingly, this approach would be an effective modification of LLNA with regard to its experimental design. Moreover, this procedure can be applied also to the standard LLNA with radioisotopes and to other modifications of the LLNA. Copyright 2005 John Wiley & Sons, Ltd.

  4. Assessment of the sensitizing potential of processed peanut proteins in Brown Norway rats: roasting does not enhance allergenicity.

    Directory of Open Access Journals (Sweden)

    Stine Kroghsbo

    Full Text Available BACKGROUND: IgE-binding of process-modified foods or proteins is the most common method for examination of how food processing affects allergenicity of food allergens. How processing affects sensitization capacity is generally studied by administration of purified food proteins or food extracts and not allergens present in their natural food matrix. OBJECTIVES: The aim was to investigate if thermal processing increases sensitization potential of whole peanuts via the oral route. In parallel, the effect of heating on sensitization potential of the major peanut allergen Ara h 1 was assessed via the intraperitoneal route. METHODS: Sensitization potential of processed peanut products and Ara h 1 was examined in Brown Norway (BN rats by oral administration of blanched or oil-roasted peanuts or peanut butter or by intraperitoneal immunization of purified native (N-, heated (H- or heat glycated (G-Ara h 1. Levels of specific IgG and IgE were determined by ELISA and IgE functionality was examined by rat basophilic leukemia (RBL cell assay. RESULTS: In rats dosed orally, roasted peanuts induced significant higher levels of specific IgE to NAra h 1 and 2 than blanched peanuts or peanut butter but with the lowest level of RBL degranulation. However, extract from roasted peanuts was found to be a superior elicitor of RBL degranulation. Process-modified Ara h 1 had similar sensitizing capacity as NAra h 1 but specific IgE reacted more readily with process-modified Ara h 1 than with native. CONCLUSIONS: Peanut products induce functional specific IgE when dosed orally to BN rats. Roasted peanuts do not have a higher sensitizing capacity than blanched peanuts. In spite of this, extract from roasted peanuts is a superior elicitor of RBL cell degranulation irrespectively of the peanut product used for sensitization. The results also suggest that new epitopes are formed or disclosed by heating Ara h 1 without glucose.

  5. Authentication of food allergen quality by physicochemical and immunological methods

    DEFF Research Database (Denmark)

    Sancho, A I; Hoffmann-Sommergruber, K; Alessandri, S

    2010-01-01

    Purified allergens are required to detect cross-contamination with other allergenic foods and to understand allergen interaction with other components of the food matrix. Pure allergens are also used for the diagnosis and treatment of food allergies. For example, serological methods are being dev...

  6. Parvalbumin--the major tropical fish allergen.

    Science.gov (United States)

    Lim, Dawn Li-Chern; Neo, Keng Hwee; Yi, Fong Cheng; Chua, Kaw Yan; Goh, Denise Li-Meng; Shek, Lynette Pei-Chi; Giam, Yoke Chin; Van Bever, Hugo P S; Lee, Bee Wah

    2008-08-01

    Fish allergy is common in countries where consumption is high. Asian nations are amongst the world's largest consumers of fish but the allergen profiles of tropical fish are unknown. This study sought to evaluate the allergenicity of four commonly consumed tropical fish, the threadfin (Polynemus indicus), Indian anchovy (Stolephorus indicus), pomfret (Pampus chinensis) and tengirri (Scomberomorus guttatus). Immunoglobulin E (IgE) cross-reactivity with parvalbumin of cod fish (Gad c 1), the major fish allergen, was also studied. Detection of tropical fish and cod specific-IgE was performed by UniCap assay, and skin prick tests were also carried out. The IgE-binding components of tropical fish were identified using IgE immunoblot techniques, and cross-reactivity with Gad c 1 was assessed by ELISA inhibition and IgE immunoblot inhibition. Clinically, nine of 10 patients studied were allergic to multiple fish. All patients exhibited detectable specific-IgE to cod fish (10 of 10 skin prick test positive, eight of 10 UniCap assay positive) despite lack of previous exposure. The major allergen of the four tropical fish was the 12-kDa parvalbumin. IgE cross-reactivity of these allergens to Gad c 1 was observed to be moderate to high in the tropical fish studied. Parvalbumins are the major allergens in commonly consumed tropical fish. They are cross-reactive with each other as well as with Gad c 1. Commercial tests for cod fish appear to be sufficient for the detection of tropical fish specific-IgE.

  7. Cytochrome P450-mediated activation of the fragrance compound geraniol forms potent contact allergens

    International Nuclear Information System (INIS)

    Hagvall, Lina; Baron, Jens Malte; Boerje, Anna; Weidolf, Lars; Merk, Hans; Karlberg, Ann-Therese

    2008-01-01

    Contact sensitization is caused by low molecular weight compounds which penetrate the skin and bind to protein. In many cases, these compounds are activated to reactive species, either by autoxidation on exposure to air or by metabolic activation in the skin. Geraniol, a widely used fragrance chemical, is considered to be a weak allergen, although its chemical structure does not indicate it to be a contact sensitizer. We have shown that geraniol autoxidizes and forms allergenic oxidation products. In the literature, it is suggested but not shown that geraniol could be metabolically activated to geranial. Previously, a skin-like CYP cocktail consisting of cutaneous CYP isoenzymes, was developed as a model system to study cutaneous metabolism. In the present study, we used this system to investigate CYP-mediated activation of geraniol. In incubations with the skin-like CYP cocktail, geranial, neral, 2,3-epoxygeraniol, 6,7-epoxygeraniol and 6,7-epoxygeranial were identified. Geranial was the main metabolite formed followed by 6,7-epoxygeraniol. The allergenic activities of the identified metabolites were determined in the murine local lymph node assay (LLNA). Geranial, neral and 6,7-epoxygeraniol were shown to be moderate sensitizers, and 6,7-epoxygeranial a strong sensitizer. Of the isoenzymes studied, CYP2B6, CYP1A1 and CYP3A5 showed high activities. It is likely that CYP1A1 and CYP3A5 are mainly responsible for the metabolic activation of geraniol in the skin, as they are expressed constitutively at significantly higher levels than CYP2B6. Thus, geraniol is activated through both autoxidation and metabolism. The allergens geranial and neral are formed via both oxidation mechanisms, thereby playing a large role in the sensitization to geraniol

  8. NCTC 2544 and IL-18 production: a tool for the identification of contact allergens.

    Science.gov (United States)

    Corsini, Emanuela; Galbiati, Valentina; Mitjans, Montserrat; Galli, Corrado L; Marinovich, Marina

    2013-04-01

    Progress in understanding the mechanisms of skin sensitization, provides us with the opportunity to develop in vitro tests as an alternative to in vivo sensitization testing. Keratinocytes play a key role in all phases of skin sensitization. We have recently identified interleukin-18 (IL-18) production in keratinocyte as a potentially useful endpoint for determination of contact sensitization potential of low molecular weight chemicals. The aim of the present article is to further exploit the performance of the NCTC 2544 assay. NCTC 2544 is a commercially available skin epithelial-like cell line originating from normal human skin, which posses a good expression of cytochrome P450-dependent enzymatic activities. Cells were exposed to contact allergens (2-bromo-2-bromomethyl glutaronitrile, cinnamaldehyde, citral, diethylmaleate, dinitrochlorobenzene, glyoxal, 2-mercaptobenzothiazole, nickel sulfate, 4-nitrobenzylbromide, oxazolone, penicillin G, resorcinol, tetramethylthiuram disulfide), to pre- pro-haptens (cinnamyl alcohol, eugenol, isoeugenol, p-phenylediamine), to respiratory allergens (ammonium hexachloroplatinate, diphenylmethane diisocyanate, glutaraldehyde, hexamethylenediisocyanate, maleic anhydride, trimellitic anhydride) and to irritants (benzaldehyde, cholorobenzene, diethylphtalate, hydrobenzoic acid, lactic acid, octanoic acid, phenol, salicylic acid, sodium lauryl sulphate, sulfamic acid). Cell associated IL-18 was evaluated 24 later by ELISA. At not-cytotoxic concentrations (cell viability higher of 80%, as assessed by MTT reduction assay), all contact sensitizers, including pre-pro-haptens, induced a dose-related increase in IL-18, whereas both irritants, with the exception of sulfamic acid, and respiratory allergens failed. A total of 33 chemicals were tested, with an overall accuracy of 97%. Overall, results obtained indicated that cell-associated IL-18 might provide an in vitro tool for identification and discrimination of contact vs. respiratory

  9. IgE sensitization to food allergens and airborne allergens in relation to biomarkers of type 2 inflammation in asthma.

    Science.gov (United States)

    Patelis, A; Alving, K; Middelveld, R; James, A; Ono, J; Ohta, S; Izuhara, K; Borres, M P; Forsberg, B; Janson, C; Malinovschi, A

    2018-05-10

    We have recently reported that sensitization to food allergens and sensitization to airborne allergens had independent associations with increased fraction of exhaled nitric oxide (FeNO) and blood eosinophils in middle-aged adults and in young subjects with asthma. To investigate the relation between IgE sensitization and several type 2 inflammation biomarkers in adult asthmatics. FeNO, urinary eosinophil-derived neurotoxin (U-EDN), serum eosinophil cationic protein (S-ECP) and periostin were measured in 396 asthmatics, aged 17-76 years, from the Swedish GA2LEN study. Sensitization to airborne allergens was examined with skin prick tests (≥3 mm wheal) and sensitization to food allergens with measurement of specific IgE (≥0.35 kU/L). Asthmatics sensitized to food allergens had higher FeNO, 22.3 ppb (18.6, 26.7) vs 16.1 ppb (14.2, 18.2) (P = .005), S-ECP, 17.7 mg/L (14.8, 21.1) vs 12.8 mg/L (10.9, 14.9) (P = .01), and periostin, 73.7 (67.5, 80.3) ng/mL vs 59.9 (55.8, 64.2) ng/mL (P = .003), than non-sensitized subjects. Periostin levels in this group were also significantly higher than in the group sensitized only to airborne allergens (P = .01). Sensitization to food allergens related independently to FeNO (P = .02), S-ECP (P = .006) and periostin (P = .004), whereas sensitization only to airborne allergens related only to FeNO (P = .02) after adjustments for age, sex, height, weight and smoking history. FeNO correlated weakly with S-ECP (r = .17, P < .001), periostin (r = .19, P < .001) and U-EDN (0.16, P < .001). S-ECP also correlated weakly with U-EDN (r = .12, P = .02). None of the correlations between the remaining pairs of markers of type 2 inflammation were significant. Sensitization to food allergens related to several local and systemic type 2 inflammation markers, such as FeNO, S-ECP and periostin. Assessing the profile of allergic sensitization, including to food allergens, might improve the understanding and

  10. Thresholds in chemical respiratory sensitisation.

    Science.gov (United States)

    Cochrane, Stella A; Arts, Josje H E; Ehnes, Colin; Hindle, Stuart; Hollnagel, Heli M; Poole, Alan; Suto, Hidenori; Kimber, Ian

    2015-07-03

    There is a continuing interest in determining whether it is possible to identify thresholds for chemical allergy. Here allergic sensitisation of the respiratory tract by chemicals is considered in this context. This is an important occupational health problem, being associated with rhinitis and asthma, and in addition provides toxicologists and risk assessors with a number of challenges. In common with all forms of allergic disease chemical respiratory allergy develops in two phases. In the first (induction) phase exposure to a chemical allergen (by an appropriate route of exposure) causes immunological priming and sensitisation of the respiratory tract. The second (elicitation) phase is triggered if a sensitised subject is exposed subsequently to the same chemical allergen via inhalation. A secondary immune response will be provoked in the respiratory tract resulting in inflammation and the signs and symptoms of a respiratory hypersensitivity reaction. In this article attention has focused on the identification of threshold values during the acquisition of sensitisation. Current mechanistic understanding of allergy is such that it can be assumed that the development of sensitisation (and also the elicitation of an allergic reaction) is a threshold phenomenon; there will be levels of exposure below which sensitisation will not be acquired. That is, all immune responses, including allergic sensitisation, have threshold requirement for the availability of antigen/allergen, below which a response will fail to develop. The issue addressed here is whether there are methods available or clinical/epidemiological data that permit the identification of such thresholds. This document reviews briefly relevant human studies of occupational asthma, and experimental models that have been developed (or are being developed) for the identification and characterisation of chemical respiratory allergens. The main conclusion drawn is that although there is evidence that the

  11. Inactivation of dust mites, dust mite allergen, and mold from carpet.

    Science.gov (United States)

    Ong, Kee-Hean; Lewis, Roger D; Dixit, Anupma; MacDonald, Maureen; Yang, Mingan; Qian, Zhengmin

    2014-01-01

    Carpet is known to be a reservoir for biological contaminants, such as dust mites, dust mite allergen, and mold, if it is not kept clean. The accumulation of these contaminants in carpet might trigger allergies or asthma symptoms in both children and adults. The purpose of this study is to compare methods for removal of dust mites, dust mite allergens, and mold from carpet. Carpets were artificially worn to simulate 1 to 2 years of wear in a four-person household. The worn carpets were inoculated together with a common indoor mold (Cladosporium species) and house dust mites and incubated for 6 weeks to allow time for dust mite growth on the carpet. The carpets were randomly assigned to one of the four treatment groups. Available treatment regimens for controlling carpet contaminants were evaluated through a literature review and experimentation. Four moderately low-hazard, nondestructive methods were selected as treatments: vacuuming, steam-vapor, Neem oil (a natural tree extract), and benzalkonium chloride (a quaternary ammonium compound). Steam vapor treatment demonstrated the greatest dust mite population reduction (p 0.05) for both physical and chemical methods. The steam-vapor treatment effectively killed dust mites and denatured dust mite allergen in the laboratory environment.

  12. Allergen immunotherapy for allergic respiratory diseases

    Science.gov (United States)

    Cappella, Antonio; Durham, Stephen R.

    2012-01-01

    Allergen specific immunotherapy involves the repeated administration of allergen products in order to induce clinical and immunologic tolerance to the offending allergen. Immunotherapy is the only etiology-based treatment that has the potential for disease modification, as reflected by longterm remission following its discontinuation and possibly prevention of disease progression and onset of new allergic sensitizations. Whereas subcutaneous immunotherapy is of proven value in allergic rhinitis and asthma there is a risk of untoward side effects including rarely anaphylaxis. Recently the sublingual route has emerged as an effective and safer alternative. Whereas the efficacy of SLIT in seasonal allergy is now well-documented in adults and children, the available data for perennial allergies and asthma is less reliable and particularly lacking in children. This review evaluates the efficacy, safety and longterm benefits of SCIT and SLIT and highlights new findings regarding mechanisms, potential biomarkers and recent novel approaches for allergen immunotherapy. PMID:23095870

  13. Top-down and bottom-up characterization of nitrated birch pollen allergen Bet v 1a with CZE hyphenated to an Orbitrap mass spectrometer.

    Science.gov (United States)

    Gusenkov, Sergey; Stutz, Hanno

    2018-02-01

    Tyrosine (Tyr) residues of the major pollen allergen of birch Betula verrucosa, Bet v 1a, were nitrated by peroxynitrite. This modification enhances the allergenicity. Modified tyrosines were identified by analyzing intact allergen variants in combination with top-down and bottom-up approaches. Therefore, a laboratory-built sheath-liquid assisted ESI interface was applied for hyphenation of CE to an Orbitrap mass spectrometer to localize individual nitration sites. The major focus was on identification of primary nitration sites. The top-down approach unambiguously identified Tyr 5 as the most prominent modification site. Fragments from the allergen core and the C-terminal part carried up to three potential nitration sites, respectively. Thus, a bottom-up approach with tryptic digest was used as a complementary strategy which allowed for the unambiguous localization of nitration sites within the respective peptides. Nitration propensity for individual Tyr residues was addressed by comparison of MS signals of nitrated peptides relative to all cognates of homolog primary sequence. Combined data identified surface exposed Tyr 5 and Tyr 66 as major nitration sites followed by less accessible Tyr 158 whereas Tyr 81, 83 and 150 possess a lower nitration tendency and are apparently modified in variants with higher nitration levels. © 2018 The Authors. Electrophoresis published by Wiley-VCH Verlag GmbH & Co. KGaA.

  14. 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

    DEFF Research Database (Denmark)

    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 sy...

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

    Science.gov (United States)

    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.

  16. Modified NASA-Lewis chemical equilibrium code for MHD applications

    Science.gov (United States)

    Sacks, R. A.; Geyer, H. K.; Grammel, S. J.; Doss, E. D.

    1979-01-01

    A substantially modified version of the NASA-Lewis Chemical Equilibrium Code was recently developed. The modifications were designed to extend the power and convenience of the Code as a tool for performing combustor analysis for MHD systems studies. The effect of the programming details is described from a user point of view.

  17. Prevention of diabetes in NOD mice by repeated exposures to a contact allergen inducing a sub-clinical dermatitis

    DEFF Research Database (Denmark)

    Engkilde, Kaare; Buschard, Karsten; Hansen, Axel Jacob Kornerup

    2010-01-01

    Type 1 diabetes is an autoimmune disease, while allergic contact dermatitis although immune mediated, is considered an exposure driven disease that develops due to epicutaneous 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...

  18. Preparation of patient-related allergens for hyposensitization. Qualitative aspects

    DEFF Research Database (Denmark)

    Poulsen, L K; Søndergaard, I; Weeke, B

    1988-01-01

    An affinity chromatography method for preparation of patient-related antigens from commercially available allergen extracts has been investigated. IgG1,2,4 from a patient previously hyposensitized with dog hair and dandruff allergen was bound to protein A-sepharose. Secondly, commercial allergen ...

  19. Overview of the most commonly used methods in allergen characterization

    Directory of Open Access Journals (Sweden)

    TANJA CIRKOVIC VELICKOVIC

    2005-03-01

    Full Text Available The characterization of an allergen is a troublesome and difficult process, as it requires both the precise biochemical characterization of a (glycoprotein molecule and the establishment of its susceptibility to IgE antibodies, as they are themain link to histamine release in some hypersensitivity states (type I allergies. As the characterization of an allergen includes molecular weight determination of the allergenic molecule, its structure determination, physicochemical properties, IgE binding properties of the allergen molecule, and its allergenicity, an overal review of which biochemical and immunochemical methods are used in achieving this goal are presented in this paper. The information on the molecular level on the stuctures of allergens indicates that allergens are considerably heterogeneous protein structures, and that there is no particular aminoacid sequence which is responsible for the allergenicity. Therefore, information gained from detailed structural, functional and immunochemical studies of these intriguing molecules, which nowadaysmodulate a variety of pathophysiological conditions, would greatly improve our understanding of the underlying disease mechanisms, and the way to handle them.

  20. Reactive chemically modified piezoelectric crystal detectors: A new class of high-selectivity sensors

    International Nuclear Information System (INIS)

    Fadeev, A.Yu.; Filatov, A.L.; Lisichkin, G.V.

    1994-01-01

    A great number of works have focused on the study of properties of modified piezoelectric quartz crystal detectors (PQCDs) coated with sorbing substrates and on applying sensors based on them for the analysis of diluted gas mixtures and solutions. This work offers a new class of gravemetric sensors characterized by a reversible chemical reaction that occurs on their surface. Silica films are proposed as a sorbing coating of quartz detectors, and a chemical modification of a surface is suggested for covalent fixation of the necessary compounds. PQCDs were chemically modified with reactive diene derivatives that can also act as dienophiles. Hexachlorocyclopentadiene (HCCPD, resonater I) and cyclopentadiene (CPD, resonator II) were fixed on a PQCD surface in several stages. After treatment with the resonaters, the PQCD in a CPD gas phase exhibited time dependent frequency shifts from 20-100 Hz. The results suggest that there is a reversible chemical reaction on the electrode surface of resonators I and II when they interact with CPD vapors. Therefore, PQCDs modified with reactive dienes were prepared for the first time and may be employed as selective sensors for CPD

  1. Occupational allergens

    NARCIS (Netherlands)

    Terwoert, J.

    2014-01-01

    Allergens are substances that may cause a hypersensitivity (allergy) of the immune system. After acquiring this hypersensitivity, further exposure to the same substance may result in allergic skin disease such as allergic contact dermatitis, or allergic airway disease such as allergic rhinitis or

  2. X-Ray Photoelectron Spectroscopic Characterization of Chemically Modified Electrodes Used as Chemical Sensors and Biosensors: A Review

    Directory of Open Access Journals (Sweden)

    Elio Desimoni

    2015-04-01

    Full Text Available The characterization of chemically modified sensors and biosensors is commonly performed by cyclic voltammetry and electron microscopies, which allow verifying electrode mechanisms and surface morphologies. Among other techniques, X-ray photoelectron spectroscopy (XPS plays a unique role in giving access to qualitative, quantitative/semi-quantitative and speciation information concerning the sensor surface. Nevertheless, XPS remains rather underused in this field. The aim of this paper is to review selected articles which evidence the useful performances of XPS in characterizing the top surface layers of chemically modified sensors and biosensors. A concise introduction to X-ray Photoelectron Spectroscopy gives to the reader the essential background. The application of XPS for characterizing sensors suitable for food and environmental analysis is highlighted.

  3. Quantifying Dustiness, Specific Allergens, and Endotoxin in Bulk Soya Imports

    Directory of Open Access Journals (Sweden)

    Howard J. Mason

    2017-11-01

    Full Text Available Soya is an important bulk agricultural product often transported by sea as chipped beans and/or the bean husks after pelletisation. There are proven allergens in both forms. Bulk handling of soya imports can generate air pollution containing dust, allergens, and pyrogens, posing health risks to dockside workers and surrounding populations. Using an International Organization for Standardization (ISO standardised rotating drum dustiness test in seven imported soya bulks, we compared the generated levels of dust and two major soya allergens in three particle sizes related to respiratory health. Extractable levels of allergen and endotoxin from the bulks showed 30–60 fold differences, with levels of one allergen (hydrophobic seed protein and endotoxin higher in husk. The generated levels of dust and allergens in the three particle sizes also showed very wide variations between bulks, with aerolysed levels of allergen influenced by both the inherent dustiness and the extractable allergen in each bulk. Percentage allergen aerolysed from pelletized husk—often assumed to be of low dustiness—after transportation was not lower than that from chipped beans. Thus, not all soya bulks pose the same inhalation health risk and reinforces the importance of controlling dust generation from handling all soya bulk to as low as reasonably practicable.

  4. Development of hypo-allergenic apples: silencing of the major allergen Mal d 1 gene in "Elstar" apple and the effect of grafting

    DEFF Research Database (Denmark)

    Krath, Britta; Eriksen, Folmer Damsted; Pedersen, Bjarne H.

    2009-01-01

    Many people who are allergic to birch pollen are also allergic to apple fruit, due to cross-allergenicity. Since apples are the most extensively consumed fruit in Europe, it is highly relevant to develop a hypo-allergenic apple. Apples with significantly reduced levels of the allergen, Mal d 1, may...

  5. Surface-modified polymeric pads for enhanced performance during chemical mechanical planarization

    International Nuclear Information System (INIS)

    Deshpande, S.; Dakshinamurthy, S.; Kuiry, S.C.; Vaidyanathan, R.; Obeng, Y.S.; Seal, S.

    2005-01-01

    The chemical mechanical planarization (CMP) process occurs at an atomic level at the slurry/wafer interface and hence slurries and polishing pads play a critical role in their successful implementation. Polyurethane is a commonly used polymer in the manufacturing of CMP pads. These pads are incompatible with some chemicals present in the CMP slurries, such as hydrogen peroxide. To overcome these problems, Psiloquest has developed new Application Specific Pads (ASP). Surface of such pads has been modified by depositing a thin film of tetraethyl orthosilicate using plasma-enhanced chemical vapor deposition (PECVD) process. In the present study, mechanical properties of such coated pads have been investigated using nanoindentation. The surface morphology and the chemistry of the ASP were studied using scanning electron microcopy, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy techniques. It was observed that mechanical and chemical properties of the pad top surface are a function of the PECVD coating time. Such PECVD-treated pads are found to be hydrophilic and do not require storage in aqueous media during the not-in-use period. The metal removal rate using such surface-modified polishing pads was found to increase linearly with the PECVD coating time

  6. Oxidative Stress: Promoter of Allergic Sensitization to Protease Allergens?

    NARCIS (Netherlands)

    van Rijt, Leonie S.; Utsch, Lara; Lutter, René; van Ree, Ronald

    2017-01-01

    Allergies arise from aberrant T helper type 2 responses to allergens. Several respiratory allergens possess proteolytic activity, which has been recognized to act as an adjuvant for the development of a Th2 response. Allergen source-derived proteases can activate the protease-activated receptor-2,

  7. Controlling allergens in animal rooms by using curtains

    DEFF Research Database (Denmark)

    Krohn, Thomas Cæcius; Itter, Gabi; Fosse, Richard

    2006-01-01

    The reduction and control of allergens in the animal facility is important for staff working with laboratory animals. This study was designed to evaluate the efficiency of perforated Makrolon curtains in front of racks as a method to reduce the amount of allergen in the animal room. The experimen......The reduction and control of allergens in the animal facility is important for staff working with laboratory animals. This study was designed to evaluate the efficiency of perforated Makrolon curtains in front of racks as a method to reduce the amount of allergen in the animal room....... The experimental situation we studied provides some information regarding allergen disposition in animal rooms but is clearly artificial and does not reflect a typical, ‘real-world’ environment in terms of preventing exposure of workers to allergens. Plastic curtains with holes were placed in front of racks......, and a corridor between the racks and a curtain was present. The room was ventilated with air, which was blown into the room through the middle of the corridor, flowing downstream and passing through the holes in the curtain. This set-up resulted in air flow from the corridor through the curtain. Air samples were...

  8. Osteogenesis ability of biomimetic modified 3Y-TZP ceramic using chemical treatment

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Shih-Kuang [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China); Chang, Pai-Ling [Taoyuan General Hospital, Taoyuan 33004, Taiwan, ROC (China); Ho, Wen-Fu [Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan, ROC (China); Hsu, Hsueh-Chuan; Liao, Huei-Jyuan [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China); Wu, Shih-Ching, E-mail: scwu@ctust.edu.tw [Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taichung 40601, Taiwan, ROC (China)

    2015-12-01

    In this study, RGD peptide derived from extracellular matrix proteins was employed to modify the surface of yttria-tetragonal zirconia polycrystal (3Y-TZP) to promote cell adhesion. The surface of 3Y-TZP ceramic specimens was first modified using chemical treatment with aqueous solutions of H{sub 3}PO{sub 4}, CH{sub 3}COOH, and NaOH, for the formation of Zr–OH surface functional groups. Then, the RGD peptide was immobilized on the surface of the 3Y-TZP through silanization method, with covalent bonding via the Zr–OH surface functional groups. From this study, the RGD peptide can successfully be grafted onto the chemical modified 3Y-TZP surface. The –OH functional groups formed on the surface of 3Y-TZP after acid/alkaline chemical treatment contribute to the grafting reaction of RGD peptides. The use of phosphoric acid solution in 3Y-TZP surface treatment before RGD peptide grafting for biomimetic modification can significantly enhance cell adhesion, proliferation, and differentiation. - Highlights: • This study successfully immobilized the peptides onto the surface of zirconia. • Acid/alkaline chemical treatment promotes the formation of − OH functional groups. • The use of phosphoric acid solution produced the formation of most − OH. • Peptides can significantly enhance cell adhesion, proliferation, and differentiation.

  9. What do we know about plant food allergens?

    DEFF Research Database (Denmark)

    Jenkins, J. A.; Sancho, A. I.; Madsen, Charlotte Bernhard

    2005-01-01

    databases has allowed their classification into families. This has shown that plant food allergens fall into four main families, with the prolamin superfamily (including the 2S albumins, nonspecific lipid transfer proteins and cc-amylase inhibitors) predominating, followed by the family of allergens related...... to the major birch pollen allergen, Bet v 1, and the cupin superfamily, including the I IS and 7S seed storage globulins. Future studies will be required to allow us to begin understand what it is about these protein families - whether it be their abundance, stability or some as yet unidentified factor...... - that is predisposing certain family members to becoming allergens....

  10. New Trends in Food Allergens Detection: Toward Biosensing Strategies.

    Science.gov (United States)

    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.

  11. Tropomyosin and Actin Identified as Major Allergens of the Carpet Clam (Paphia textile and the Effect of Cooking on Their Allergenicity

    Directory of Open Access Journals (Sweden)

    Zailatul Hani Mohamad Yadzir

    2015-01-01

    Full Text Available Objectives. To identify the major allergenic proteins of clam (Paphia textile and to investigate the effect of different cooking methods on the allergenicity of these identified proteins. Methods. Clam protein extracts were separated by denaturing polyacrylamide gel electrophoresis. IgE reactive proteins were then analyzed by immunoblotting with sera from patients with positive skin prick tests (SPT to the raw clam extract. Mass spectrometry was used to identify the major allergenic proteins of this clam. Results. Raw extract showed 12 protein bands (18–150 kDa. In contrast, fewer protein bands were seen in the boiled extract; those ranging from 40 to 150 kDa were denatured. The protein profiles were similarly altered by frying or roasting. The immunoblots of raw and boiled extracts yielded 10 and 2 IgE-binding proteins, respectively. The fried and roasted extracts showed only a single IgE-binding protein at 37 kDa. Mass spectrometry analysis of the 37 and 42 kDa major allergens indicated that these spots were tropomyosin and actin, respectively. Conclusion. The two major allergens of Paphia textile were identified as the thermostable tropomyosin and a new thermolabile allergen actin.

  12. Air-conditioner filters enriching dust mites allergen.

    Science.gov (United States)

    Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

    2015-01-01

    We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (Pair-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens.

  13. Air Pollution and Climate Change Effects on Allergies in the Anthropocene: Abundance, Interaction, and Modification of Allergens and Adjuvants.

    Science.gov (United States)

    Reinmuth-Selzle, Kathrin; Kampf, Christopher J; Lucas, Kurt; Lang-Yona, Naama; Fröhlich-Nowoisky, Janine; Shiraiwa, Manabu; Lakey, Pascale S J; Lai, Senchao; Liu, Fobang; Kunert, Anna T; Ziegler, Kira; Shen, Fangxia; Sgarbanti, Rossella; Weber, Bettina; Bellinghausen, Iris; Saloga, Joachim; Weller, Michael G; Duschl, Albert; Schuppan, Detlef; Pöschl, Ulrich

    2017-04-18

    Air pollution and climate change are potential drivers for the increasing burden of allergic diseases. The molecular mechanisms by which air pollutants and climate parameters may influence allergic diseases, however, are complex and elusive. This article provides an overview of physical, chemical and biological interactions between air pollution, climate change, allergens, adjuvants and the immune system, addressing how these interactions may promote the development of allergies. We reviewed and synthesized key findings from atmospheric, climate, and biomedical research. The current state of knowledge, open questions, and future research perspectives are outlined and discussed. The Anthropocene, as the present era of globally pervasive anthropogenic influence on planet Earth and, thus, on the human environment, is characterized by a strong increase of carbon dioxide, ozone, nitrogen oxides, and combustion- or traffic-related particulate matter in the atmosphere. These environmental factors can enhance the abundance and induce chemical modifications of allergens, increase oxidative stress in the human body, and skew the immune system toward allergic reactions. In particular, air pollutants can act as adjuvants and alter the immunogenicity of allergenic proteins, while climate change affects the atmospheric abundance and human exposure to bioaerosols and aeroallergens. To fully understand and effectively mitigate the adverse effects of air pollution and climate change on allergic diseases, several challenges remain to be resolved. Among these are the identification and quantification of immunochemical reaction pathways involving allergens and adjuvants under relevant environmental and physiological conditions.

  14. Structural analysis of linear and conformational epitopes of allergens

    Science.gov (United States)

    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

  15. Purification and characterization of allergens from Xanthium strumarium pollen.

    Science.gov (United States)

    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.

  16. Prevalence of food and airborne allergens in allergic patients in Kerman

    Directory of Open Access Journals (Sweden)

    Hamed Fouladseresht

    2014-07-01

    Full Text Available Background: Detection of various environmental allergens is the major challenge in allergic diseases and the only treatment is avoiding these allergens. The aim of this study was to determine the prevalence of food and airborne allergens in allergic patients using Skin Prick Test (SPT. Methods: A cross-sectional study was done on clinically confirmed patients of atopic-dermatitis (n=54, allergenic-rhinitis (n=64 and chronic-urticaria (n=39 who referred to asthma and allergy clinic at Afzali-Pour hospital in Kerman during 2008-2010. Skin prick test was done using allergen extracts to determine the patients' sensitivity to food and airborne antigens. Results: Fifty-nine percent of patients responded to at least one allergen. Allergy to airborne and food allergens was 55.9 % and 21.7%, respectively. Chenopodiaceae (22.9% and egg white (10.2% were most prevalent airborne and food allergens. Allergy to cockroach, egg white, egg yolk and tomato was significantly higher in males than in females (P<0.05. Conclusion: The results indicated that allergy to food and airborne allergens is different depending on the nutrition and environmental conditions.

  17. Sensitization to fungal allergens: Resolved and unresolved issues

    Directory of Open Access Journals (Sweden)

    Yuma Fukutomi

    2015-10-01

    Despite its importance in the management of allergic diseases, precise recognition of species-specific IgE sensitization to fungal allergens is often challenging because the majority of fungal extracts exhibit broad cross-reactivity with taxonomically unrelated fungi. Recent progress in gene technology has contributed to the identification of specific and cross-reactive allergen components from different fungal sources. However, data demonstrating the clinical relevance of IgE reactivity to these allergen components are still insufficient.

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

    Science.gov (United States)

    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.

  19. Characterisation of chemically-modified proteins by electrospray ionisation mass spectrometry

    International Nuclear Information System (INIS)

    Bennett, K.L.

    1996-09-01

    Electrospray mass spectrometry (ESI-MS) has been used to examine a range of intact monoclonal antibodies (MAbs), antibody fragments such as F(ab') 2 , F ab and F c , chemically-modified fragments and a range of other chemically-modified peptides and proteins as part of a broader study aimed at establishing ESI-MS as a method for the characterisation of radioimmunoconjugates (radiolabelled monoclonal antibodies). For example, the addition of up to 10 biotin molecules to the 'papain-sensitive' 50 kDa F ab fragment can be easily detected in ESI mass spectra. For intact MAbs, however, it is only possible to detect average shifts in the mass of intact antibodies following modification. Successful ESI-MS analysis of complexes formed between chelators and other small molecules conjugated to synthetic peptides, hen egg-white Iysozyme (HEL) (M r 14 306) and horse heart myoglobin (M r 16 951) has been demonstrated. ESI-MS offers considerable advantages compared with existing methods for the characterisation of chemically-conjugated proteins including speed and sensitivity of analysis and the capability for obtaining specific structural information. The conditions for ESI-MS of intact MAbs and MAb fragments have been examined in detail and it was found that 150 kDa MAbs generally required lower sample concentration and higher skimmer potentials compared with the 50 kDa F ab fragment and other lower molecular weight proteins. In addition, the m/z range over which ions from MAbs were observed was higher (m/z ∼2000-4500) than for smaller proteins. ESI-MS was also found to be useful for probing the action of the protease papain, that is used to generate MAb fragments (F(ab) '2, F ab and F c ). Further, different sensitivities to papain for different MAb preparations was demonstrated. Finally, the tandem mass spectra of a range of peptides modified by iodine and biotin were examined. In the case of biotinylated peptides, a characteristic fragment ion was identified that could

  20. Spreading of occupational allergens: laboratory animal allergens on hair-covering caps and in mattress dust of laboratory animal workers

    NARCIS (Netherlands)

    Krop, Esmeralda J. M.; Doekes, Gert; Stone, Martin J.; Aalberse, Rob C.; van der Zee, Jaring S.

    2007-01-01

    BACKGROUND: Family members of laboratory animal workers are at risk of developing allergy to laboratory animals. Little is known about the spreading of laboratory animal allergens outside the animal facilities. OBJECTIVE: To assess the presence of laboratory animal allergens in dust collected from

  1. Skin Barrier Function and Allergens

    DEFF Research Database (Denmark)

    Engebretsen, Kristiane Aasen; Thyssen, Jacob Pontoppidan

    2016-01-01

    The skin is an important barrier protecting us from mechanical insults, microorganisms, chemicals and allergens, but, importantly, also reducing water loss. A common hallmark for many dermatoses is a compromised skin barrier function, and one could suspect an elevated risk of contact sensitization...... and skin barrier status. Psoriasis has traditionally been regarded a Th1-dominated disease, but the discovery of Th17 cells and IL-17 provides new and interesting information regarding the pathogenesis of the disease. Research suggests an inverse relationship between psoriasis and CA, possibly due......) and Th2 (AD) have been proposed as an explanation. Finally, there is convincing evidence that exposure to irritants increases the risk of CS, and patients with ICD are, therefore, at great risk of developing CA. Skin irritation leads to the release of IL-1 and TNF-α, which affects the function of antigen...

  2. Cosmetic Contact Allergens

    Directory of Open Access Journals (Sweden)

    An Goossens

    2016-02-01

    Full Text Available This article presents trends in the frequency of cosmetics as causal factors of allergic contact dermatitis during a 26-year period in 14,911 patients patch-tested between 1990 and 2014, and discusses the cosmetic allergens identified during the last six years (2010–2015 in 603 patients out of 3105 tested. The data were retrieved from, and evaluated with, a patient database developed in-house. The results show the increasing importance of cosmetic allergies, up to 25% of the patients tested during the last five-year period. As expected, fragrance materials, preservatives, and hair dyes were the most frequent culprits, but a great variety of other allergenic ingredients were involved as well. This underlines the need of additional and extensive patch testing with the patient’s products used and their ingredients.

  3. Gal d 6 is the second allergen characterized from egg yolk.

    Science.gov (United States)

    Amo, Alvaro; Rodríguez-Pérez, Rosa; Blanco, Juan; Villota, Julian; Juste, Sonsoles; Moneo, Ignacio; Caballero, María Luisa

    2010-06-23

    Only one allergen from the egg yolk, alpha-livetin (Gal d 5) has been described thus far. A new egg yolk allergen was detected studying 27 egg allergic patients. The study was performed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and IgE-immunoblotting and IgE-immunoblotting-inhibition assays. An egg yolk extract was fractioned by reverse-phase high-performance liquid chromatography (RP-HPLC), and the new allergen detected was characterized by N-terminal amino acid analysis. A total of 5 of the 27 patients (18%) detected a yolk allergen of an apparent molecular weight of 35 kDa by SDS-PAGE. Heating and reduction treatments did not affect its allergenicity, although digestion with simulated gastric fluid diminished the IgE-binding capacity of the allergen. The N-terminal amino acid sequence corresponded with the YGP42 protein, a fragment of the vitellogenin-1 precursor. Thus, a second egg yolk allergen has been described and designated Gal d 6 by the World Health Organization (WHO)/International Union of Immunological Societies (IUIS) Allergen Nomenclature Subcommittee.

  4. Food Production and Processing Considerations of Allergenic Food Ingredients: A Review

    Science.gov (United States)

    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

  5. Proficiency test for allergens in food 2014

    NARCIS (Netherlands)

    Bremer, M.G.E.G.; Alamenou, P.; Elbers, I.J.W.

    2015-01-01

    In the autumn of 2014 a proficiency test for allergens in baby cereal was organized by RIKILT, Wageningen UR. This PT-test enabled laboratories to evaluate their competence for the analysis of allergens in baby cereal. Both quantitative and qualitative methods were accepted. The proficiency test was

  6. [Specific immunotherapy. Hyposensitization with allergens].

    Science.gov (United States)

    Wedi, B; Kapp, A

    2004-04-01

    Successful allergen-specific immunotherapy (SIT) induces complex immunologic chan-ges resulting in reduced allergic inflammatory reactions. SIT has long-term effects in mild forms of inhalant allergies and is effective even when standard pharmacotherapy fails. Moreover, the risk to develop additional allergic sensitizations and the development of asthma is significantly reduced in children with allergic rhinitis. SIT is the treatment of choice in patients with systemic reactions to hymenoptera venoms. Although the exact effector mechanisms of SIT still have to be clarified, the most probable effect is a modulation of regulatory T cells associated with a switch of allergen-specific B-cells towards IgG4 production. The critical point to insure efficacy and safety is the selection of patients and allergens, task best performed by a specialist trained in allergology. Further details are available in the position papers of the German allergy societies - DGAI(Deutsche Gesellschaft fiir Allergologie und Klinische Immunologie) and ADA (Arzte-verband Deutscher Allergologen) - which can be found at www.dgaki.de.

  7. Degradation and removal of soybean allergen in Japanese soy sauce.

    Science.gov (United States)

    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.

  8. Purification and characterization of the glycoprotein allergen from Prosopis juliflora pollen.

    Science.gov (United States)

    Thakur, I S

    1991-02-01

    Highly active glycoprotein allergens have been isolated from pollen of Prosopis juliflora by a combination of Sephadex G-100 gel filtration and Sodium dodecyl sulphate-Poly-acrylamide gel electrophoresis. The glycoprotein fraction was homogeneous, and had molecular weight 20,000. The purified glycoprotein allergen contained 20% carbohydrate, mainly arabinose and galactose. Enzymatic digestion of glycoprotein with protease released glycopeptides of molecular weight ranging from less than 1,000 to more than 5,000 on Sephadex G-25 gel filtration. Antigenicity or allergenicity testing of these glycopeptides by immunodiffusion, immunoelectrophoresis, and radioallergosorbent test indicated complete loss of allergenic activity after digestion with protease whereas incubation with beta-D-galactosidase and periodate oxidation had little affect on the allergenic activity of the glycoprotein fraction. But incubation with alpha-D-glucosidase did not affect the allergenic activity significantly. All these tests indicated that protein played significant role in allergenicity of P. juliflora pollen.

  9. Mechano-sorptive creep of Portuguese pinewood chemically modified

    Directory of Open Access Journals (Sweden)

    Barroso Lopes Duarte

    2014-03-01

    Full Text Available The effect of chemical modification on mechano-sorptive creep in bending was studied by experimental work. Stakes with 20 × 20 × 400 mm RTL of Portuguese wood species (Pinus pinaster Aiton modified with 1,3-dimethylol-4,5- dihydroxyethyleneurea (DMDHEU, m-methylated melamine resin (MMF, tetraethoxysilane (TEOS and amid wax (WA were measured under asymmetric moistening conditions over a period of 42 days (app. 1000 hours with stress level (SL of 12 MPa, according to ENV 1156.

  10. Assessing genetically modified crops to minimize the risk of increased food allergy: a review.

    Science.gov (United States)

    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.

  11. Managing Food Allergens in the U.K. Retail Supply Chain.

    Science.gov (United States)

    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.

  12. Identification of two distinct allergenic sites on ryegrass-pollen allergen, Lol p IV.

    Science.gov (United States)

    Jaggi, K S; Ekramoddoullah, A K; Kisil, F T; Dzuba-Fischer, J M; Rector, E S; Sehon, A H

    1989-04-01

    Lol p IV is an important allergen of ryegrass pollen. For the immunochemical identification of antigenic and/or allergenic site(s), murine monoclonal antibodies (MAbs) were prepared against Lol p IV. The hybridoma cell-culture supernatants were screened for anti-Lol p IV antibodies by a combination of ELISA and Western immunoblot analyses. The MAbs were finally purified from ascites on a Mono Q ion-exchange column. In a competitive radioimmunoassay with Lol p IV as the solid phase and 125I-labeled MAbs, it was established that MAbs 90, 91, 92, 93, and 94, although they differed in their relative affinities, recognized in common with one another an epitope designated as antigenic site A, whereas MAb 12 recognized a different epitope referred to as site B. Sites A and B were also demonstrated to constitute allergenic determinants of Lol p IV. Differences in the repertoire of specificities of the human IgE antibodies directed to Lol p IV were also demonstrated. Interestingly, it was found that sera from both allergic as well as from nonatopic individuals had IgG antibodies to sites A and/or B.

  13. Performing IgE serum testing due to bioinformatics matches in the allergenicity assessment of GM crops.

    Science.gov (United States)

    Goodman, Richard E

    2008-10-01

    Proteins introduced into genetically modified (GM) organisms through genetic engineering must be evaluated for their potential to cause allergic disease under various national laws and regulations. The Codex Alimentarius Commission guidance document (2003) calls for testing of serum IgE binding to the introduced protein if the gene was from an allergenic source, or the sequence of the transferred protein has >35% identity in any segment of 80 or more amino acids to a known allergen or shares significant short amino acid identities. The Codex guidance recognized that the assessment will evolve based on new scientific knowledge. Arguably, the current criteria are too conservative as discussed in this paper and they do not provide practical guidance on serum testing. The goals of this paper are: (1) to summarize evidence supporting the level of identity that indicates potential risk of cross-reactivity for those with existing allergies; (2) to provide example bioinformatics results and discuss their interpretation using published examples of proteins expressed in transgenic crops; and (3) to discuss key factors of experimental design and methodology for serum IgE tests to minimize the rate of false negative and false positive identification of potential allergens and cross-reactive proteins.

  14. Sedimentation behaviour and colloidal properties of porous, chemically modified silicas in non-aqueous solvents

    NARCIS (Netherlands)

    Vissers, J.P.C.; Laven, J.; Claessens, H.A.; Cramers, C.A.M.G.; Agterof, W.G.M.

    1997-01-01

    The sedimentation behaviour and colloidal properties of porous, chemically modified silicas dispersed in non-aqueous solvents have been studied. The free settling behaviour of non-aggregated silica suspensions could effectively be described with a modified Stokes equation that takes into account the

  15. Allergenic food introduction and risk of childhood atopic diseases.

    Directory of Open Access Journals (Sweden)

    Niels J Elbert

    Full Text Available The role of timing and diversity of allergenic food introduction in the development of childhood allergic sensitization and atopic diseases is controversial.To examine whether timing and diversity of allergenic food introduction are associated with allergic sensitization, allergy and eczema in children until age 10 years.This study among 5,202 children was performed in a population-based prospective cohort. Timing (age ≤6 months vs. >6 months and diversity (0, 1, 2 and ≥3 foods of allergenic food (cow's milk, hen's egg, peanut, tree nuts, soy and gluten introduction were assessed by questionnaires at ages 6 and 12 months. At age 10 years, inhalant and food allergic sensitization were measured by skin prick tests, and physician-diagnosed inhalant and food allergy by questionnaire. Data on parental-reported physician-diagnosed eczema were obtained from birth until age 10 years.Children introduced to gluten at age ≤6 months had a decreased risk of eczema (aOR (95% CI: 0.84 (0.72, 0.99, compared with children introduced to gluten at age >6 months. However, timing of allergenic food introduction was not associated with allergic sensitization or physician-diagnosed allergy. Children introduced to ≥3 allergenic foods at age ≤6 months had a decreased risk of physician-diagnosed inhalant allergy (0.64 (0.42, 0.98, compared with children not introduced to any allergenic food at age ≤6 months. However, diversity of allergenic food introduction was not associated with allergic sensitization, physician-diagnosed food allergy or eczema.Neither timing nor diversity of allergenic food introduction was consistently associated with childhood allergic sensitization, allergy or eczema.

  16. Children’s residential exposure to selected allergens and microbial indicators: endotoxins and (1→3-β-D-glucans

    Directory of Open Access Journals (Sweden)

    Anna Kozajda

    2013-12-01

    Full Text Available Objectives: The study was aimed at assessment of exposure to endotoxins, (1→3-β-D-glucans and mite, cockroach, cat, dog allergens present in settled dust in premises of children as agents which may be significantly correlated with the occurrence of allergic symptoms and diseases in children. Materials and Methods: The study covered 50 homes of one- or two-year-old children in Poland. Samples of settled dust were taken from the floor and the child's bed. The levels of (1→3-β-D-glucans (floor, endotoxins (floor and allergens of mite, cat, dog and cockroach (floor and bed were analyzed. Results: Average geometric concentrations (geometric standard deviation of endotoxins, (1→3-β-D-glucans, Der p1, Fel d1, Can f1 and Bla g1 in children homes were on the floor 42 166.0 EU/g (3.2, 20 478.4 ng/g (2.38, 93.9 ng/g (6.58, 119.8 ng/g (13.0, 288.9 ng/g (3.4, 0.72 U/g (4.4 and in their beds (only allergens 597.8 ng/g (14.2, 54.1 ng/g (4.4, 158.6 ng/g (3.1 0.6 U/g (2.9, respectively. When the floor was covered with the carpet, higher concentrations of endotoxins, (1→3-β-D-glucans and allergens (each type were found in the settled dust (p < 0.05. The trend was opposite in case of allergens (except dog analyzed from bed dust and significantly higher concentrations were found in the rooms with smooth floor (p < 0.05. Conclusions: Among the analyzed factors only the type of floor significantly modified both the level of biological indicators and allergens. The results of this study could be the base for verifying a hypothesis that carpeting may have a protective role against high levels of cockroach, dog and cat allergens.

  17. Allergic contact dermatitis caused by dimethylthiocarbamylbenzothiazole sulfide (DMTBS) in canvas shoes: in search of the culprit allergen.

    Science.gov (United States)

    Schuttelaar, Marie L; Meijer, Joost M; Engfeldt, Malin; Lapeere, Hilde; Goossens, An; Bruze, Magnus; Persson, Christina; Bergendorff, Ola

    2018-01-01

    During rubber vulcanization, new compounds can be formed. To report a case of allergic shoe dermatitis in which the search for the allergen ultimately led to the identification of dimethylthiocarbamylbenzothiazole sulfide (DMTBS). A female presented with eczema on her feet after wearing Sperry Top Sider® canvas sneakers. Patch testing was performed with the European baseline series, additional series, shoe materials, and extracts of shoe materials. Thin-layer chromatography (TLC) was performed for additional patch testing, and high-performance liquid chromatography and gas chromatography-mass spectometry were used for chemical analysis. Positive reactions were found to thiuram mix (+), tetramethylthiuram monosulfide (TMTM) (+), shoe material (+), and shoe extracts in eth. (++) and acetone (+). The extracts did not contain TMTM or other components of thiuram mix. TLC strips yielded a positive reaction (+) to one spot, whereas chemical analysis gave a negative result. Thereafter, a similar sneaker from another patient with shoe dermatitis was analysed, and DMBTS was identified. New extracts of the shoe of our first patient were then also shown to contain DMTBS. DMTBS as culprit allergen was confirmed by positive patch testing with a dilution series with DMTBS. DMBTS was identified as the culprit allergen in shoe dermatitis, giving rise to compound allergy. The positive reaction to TMTM was considered to represent cross-reactivity. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  18. Adsorption of Cashew Allergens to Acid-Etched Zinc Metal Particles

    Science.gov (United States)

    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...

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

    Science.gov (United States)

    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.

  20. Effect of Age on Allergen Responses of Allergic Patients in Southern Taiwan

    Directory of Open Access Journals (Sweden)

    Wen Chiang

    2004-07-01

    Full Text Available To survey airborne and food allergen patterns in southern Taiwan and to analyze the effect of age on response to different allergens, we tested samples from 4,411 allergic patients at Kaohsiung Medical University Hospital using the MAST-CLA test (new Taiwan panel. A total of 2,212 (50.1% samples showed a positive response. We grouped allergic patients into five age groups. Milk and egg white were the main food allergens in the younger groups (< 3 years old and 3-6 years old. Shrimp, crab, and shellfish were the main allergens in the groups aged 7-12, 13-18, and more than 18 years. Among airborne allergens, house dust and mites Dermatophagoides farinae and D. pteronyssinus were the main allergens in all age groups, whereas the frequency of response to cockroach allergen was low in the group aged less than 3 years, but increased in the other age groups. There was a sharp increase in the frequency of response to airborne allergens after 3 years old and a sharp decrease in response to food allergens. Among subjects allergic to both airborne and food allergens, there was a positive MAST-CLA rate of 19.9% to 26% (all five age groups, no significant difference. When we compared our results with those from Taipei Veterans General Hospital in northern Taiwan, there were significant differences for yeast, peanut, feather mix, dog dander, cockroach, D. farinae and D. pteronyssinus allergens (p < 0.01. These differences were probably caused by differences in patient location, patient age, disease patterns and allergen panels.

  1. Chemically Modified Polyvinyl Chloride for Removal of Thionine Dye (Lauth’s Violet

    Directory of Open Access Journals (Sweden)

    Helena Ma A. M. M. S. Ali

    2017-11-01

    Full Text Available The chemical modification of hydrophobic polymer matrices is an alternative way to elchange their surface properties. The introduction of sulfonic groups in the polymer changes the surface properties such as adhesion, wettability, catalytic ability, and adsorption capacity. This work describes the production and application of chemically modified polyvinyl chloride (PVC as adsorbent for dyes removal. Chemical modification of PVC was evaluated by infrared spectroscopy and elemental analysis, which indicated the presence of sulfonic groups on PVC. The chemically modified PVC (PVCDS showed an ion exchange capacity of 1.03 mmol−1, and efficiently removed the thionine dye (Lauth’s violet from aqueous solutions, reaching equilibrium in 30 min. The adsorption kinetics was better adjusted for a pseudo second order model. This result indicates that the adsorption of thionine onto PVCDS occurs by chemisorption. Among the models for the state of equilibrium, SIPS and Langmuir exhibited the best fit to the experimental results and PVCDS showed high adsorption capacities (370 mg−1. Thus, it is assumed that the system presents homogeneous characteristics to the distribution of active sites. The modification promoted the formation of surface characteristics favorable to the dye adsorption by the polymer.

  2. Dehydration and hydration behavior of metal-salt-modified materials for chemical heat pumps

    International Nuclear Information System (INIS)

    Ishitobi, Hirokazu; Uruma, Keirei; Takeuchi, Masato; Ryu, Junichi; Kato, Yukitaka

    2013-01-01

    Lithium chloride (LiCl) modified magnesium hydroxide (Mg(OH) 2 ) is a potential new material for chemical heat pumps. However, there is insufficient information concerning its dehydration and hydration behavior. In this study, the dehydration and hydration reactions, corresponding to the heat storage and the heat output operations, respectively, of authentic Mg(OH) 2 and LiCl-modified Mg(OH) 2 were investigated by thermogravimetric methods and near infrared spectroscopy. The dehydration of authentic Mg(OH) 2 proceeded as a one-step reaction. In contrast, the dehydration of LiCl-modified Mg(OH) 2 occurred in two steps. The dehydration reaction rates were increased by LiCl modification of the Mg(OH) 2 surface, while the activation energy for the first-order dehydration reaction was lowered. The mechanism for the hydration reaction of magnesium oxide (MgO) was different to that for the hydration of LiCl-modified MgO. This difference was explained by the effect of the LiCl on the MgO particle surface. - Highlights: ► LiCl-modified Mg(OH) 2 is a candidate material for chemical heat pumps. ► The dehydration reaction of LiCl-modified Mg(OH) 2 is a two-step reaction. ► The dehydration reaction of Mg(OH) 2 was enhanced by LiCl modification. ► The hydration mechanisms of authentic MgO and LiCl-modified MgO were different.

  3. Modelling allergenic risk

    DEFF Research Database (Denmark)

    Birot, Sophie

    combines second order Monte-Carlo simulations with Bayesian inferences [13]. An alternative method using second order Monte-Carlo simulations was proposed to take into account the uncertainty from the inputs. The uncertainty propagation from the inputs to the risk of allergic reaction was also evaluated...... countries is proposed. Thus, the allergen risk assessment can be performed cross-nationally and for the correct food group. Then the two probabilistic risk assessment methods usually used were reviewed and compared. First order Monte-Carlo simulations are used in one method [14], whereas the other one......Up to 20 million Europeans suffer from food allergies. Due to the lack of knowledge about why food allergies developed or how to protect allergic consumers from the offending food, food allergy management is mainly based on food allergens avoidance. The iFAAM project (Integrated approaches to Food...

  4. Purification, characterization and allergenicity assessment of 26kDa protein, a major allergen from Cicer arietinum.

    Science.gov (United States)

    Verma, Alok Kumar; Sharma, Akanksha; Kumar, Sandeep; Gupta, Rinkesh Kumar; Kumar, Dinesh; Gupta, Kriti; Giridhar, B H; Das, Mukul; Dwivedi, Premendra D

    2016-06-01

    Chickpea (CP), a legume of the family Fabaceae, is an important nutrient-rich food providing protein, essential amino acids, vitamins, dietary fibre, and minerals. Unfortunately, several IgE-binding proteins in CP have been detected that are responsible for allergic manifestations in sensitized population. Therefore, the prevalence of CP induced allergy prompted us towards purification, characterization and allergenicity assessment of a major ∼26kDa protein from chickpea crude protein extract (CP-CPE). Purification of CP 26kDa protein was done using a combination of fractionation and anion exchange chromatography. This protein was further characterized as "Chain A, crystal structure of a plant albumin" from Cicer arietinum with Mol wt 25.8kDa by Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Further, allergenic potential of purified 25.8kDa protein was assessed using in vivo and in vitro model. Purified protein showed IgE-binding capacity with sensitized BALB/c mice and CP allergic patient's sera. Enhanced levels of specific and total IgE, MCP-1, MCPT-1, myeloperoxidase, histamine, prostaglandin D2, and cysteinyl leukotriene were found in sera of mice treated with CP ∼26kDa protein. Further, expressions of Th2 cytokines (i.e. IL-4, IL-5, IL-13), transcription factors (i.e. GATA-3, STAT-6, SOCS-3) and mast cell signaling proteins (Lyn, cFgr, Syk, PLC-γ2, PI-3K, PKC) were also found increased at mRNA and protein levels in the intestines of mice treated with CP ∼26kDa protein. In addition, enhanced release of β-hexosaminidase, histamine, cysteinyl leukotriene and prostaglandin D2 were observed in RBL2H3 cell line when treated (125μg) with CP 26kDa protein. Conclusively, in vivo and in vitro studies revealed the allergenic potential of purified CP 26kDa protein. Being a potential allergen, plant albumin may play a pivotal role in CP induced allergenicity. Current study will be helpful for better development of therapeutic approaches to

  5. One-step multiplex PCR method for the determination of pecan and Brazil nut allergens in food products.

    Science.gov (United States)

    Hubalkova, Zora; Rencova, Eva

    2011-10-01

    A one-step polymerase chain reaction (PCR) method for the simultaneous detection of the major allergens of pecan and Brazil nuts was developed. Primer pairs for the amplification of partial sequences of genes encoding the allergens were designed and tested for their specificity on a range of food components. The targeted amplicon size was 173 bp of Ber e 1 gene of Brazil nuts and 72 bp of vicilin-like seed storage protein gene in pecan nuts. The primer pair detecting the noncoding region of the chloroplast DNA was used as the internal control of amplification. The intrinsic detection limit of the PCR method was 100 pg mL(-1) pecan or Brazil nuts DNA. The practical detection limit was 0.1% w/w (1 g kg(-1)). The method was applied for the investigation of 63 samples with the declaration of pecans, Brazil nuts, other different nut species or nuts generally. In 15 food samples pecans and Brazil nuts allergens were identified in the conformity with the food declaration. The presented multiplex PCR method is specific enough and can be used as a fast approach for the detection of major allergens of pecan or Brazil nuts in food. Copyright © 2011 Society of Chemical Industry.

  6. Immune response to allergens in sheep sensitized to house dust mite

    Directory of Open Access Journals (Sweden)

    Velden Joanne

    2008-10-01

    Full Text Available Abstract Background House dust mite (HDM allergens are a major cause of allergic asthma. Most studies using animal models of allergic asthma have used rodents sensitized with the 'un-natural' allergen ovalbumin. It has only recently been recognized that the use of animal models based on HDM provide a more relevant insight into the allergen-induced mechanisms that underpin human allergic disease. We have previously described a sheep model of human allergic asthma that uses Dermatophagoides pteronyssinus HDM. The present study extends our understanding of the immune effects of HDM and the allergens Der p 1 and Der p 2 in the sheep model of asthma. Methods Peripheral blood sera from non-sensitized (control sheep and sheep sensitized to HDM was collected to determine immunoglobulin (Ig reactivities to HDM, Der p 1 and Der p 2 by ELISA. Bronchoalveolar lavage (BAL fluid collected following allergen challenge was also assessed for the presence of HDM-specific antibodies. To examine the cellular immune response to HDM allergens, T cell proliferation and cutaneous responses were assessed in sensitized and control sheep. Results Strong HDM- and Der p 1-specific IgE, IgG1, IgG2 and IgA serum responses were observed in sensitized sheep, while detectable levels of HDM-specific IgG1 and IgA were seen in BAL fluid of allergen-challenged lungs. In contrast, minimal antibody reactivity was observed to Der p 2. Marked T cell proliferation and late phase cutaneous responses, accompanied by the recruitment of eosinophils, indicates the induction of a cellular and delayed-type hypersensitivity (DTH type II response by HDM and Der p 1 allergen, but not Der p 2. Conclusion This work characterizes the humoral and cellular immune effects of HDM extract and its major constituent allergens in sheep sensitized to HDM. The effects of allergen in HDM-sensitized sheep were detectable both locally and systemically, and probably mediated via enzymatic and immune actions of the

  7. Complete primary structure of a Lolium perenne (perennial rye grass) pollen allergen, Lol p III: comparison with known Lol p I and II sequences.

    Science.gov (United States)

    Ansari, A A; Shenbagamurthi, P; Marsh, D G

    1989-10-17

    The complete amino acid sequence of a Lolium perenne (rye grass) pollen allergen, Lol p III, determined by the automated Edman degradation of the protein and its selected fragments, is reported in this paper. Cleavage by enzymatic and chemical techniques established unambiguously the sequence for this 97-residue protein (Mr = 10,909), which lacks cysteine and shows no evidence of glycosylation. The sequence of Lol p III is very similar to that of another L. perenne allergen, Lol p II, which was sequenced recently; of the 97 positions in the two proteins, 57 are occupied by identical amino acids (59% identity). In addition, both allergens share a similar structure with an antibody-binding fragment of a third L. perenne allergen, Lol p I. Since human antibody responsiveness to all these three allergens is associated with HLA-DR3, and since the structure common to the three molecules shows high degrees of amphipathicity in Lol p II and III, we speculate that this common segment in the three molecules might contain or contribute to the respectively Ia/T-cell sites.

  8. Reduction of the Number of Major Representative Allergens: From Clinical Testing to 3-Dimensional Structures

    Directory of Open Access Journals (Sweden)

    Ying He

    2014-01-01

    Full Text Available Vast amounts of allergen sequence data have been accumulated, thus complicating the identification of specific allergenic proteins when performing diagnostic allergy tests and immunotherapy. This study aims to rank the importance/potency of the allergens so as to logically reduce the number of allergens and/or allergenic sources. Meta-analysis of 62 allergenic sources used for intradermal testing on 3,335 allergic patients demonstrated that in southern China, mite, sesame, spiny amaranth, Pseudomonas aeruginosa, and house dust account for 88.0% to 100% of the observed positive reactions to the 62 types of allergenic sources tested. The Kolmogorov-Smironov Test results of the website-obtained allergen data and allergen family featured peptides suggested that allergen research in laboratories worldwide has been conducted in parallel on many of the same species. The major allergens were reduced to 21 representative allergens, which were further divided into seven structural classes, each of which contains similar structural components. This study therefore has condensed numerous allergenic sources and major allergens into fewer major representative ones, thus allowing for the use of a smaller number of allergens when conducting comprehensive allergen testing and immunotherapy treatments.

  9. 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.

    Science.gov (United States)

    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

  10. Prosopis juliflora pollen allergen induced hypersensitivity and anaphylaxis studies in guinea pigs.

    Science.gov (United States)

    Thakur, I S

    1986-11-01

    In vivo and in vitro allergenic activities of Prosopis juliflora pollen allergens were measured in guinea pigs. Intracutaneous skin test showed an early wheal flare response and a late erythema-redness, sensitized with various concentrations (100, 50, 25, 5 and 1.5 micrograms/ml) of Prosopis juliflora pollen extract after administration of a challenging dose. A 50 micrograms/ml sensitizing dose of Prosopis juliflora pollen allergen gave optimum skin response as both early and late effects. The nature of immunochemical reactivity between pollen allergens and reaginic antibodies were further characterized by histamine release test, gel diffusion test, radioallergosorbent test and passive cutaneous anaphylaxis test. These tests confirm allergenicity caused by Prosopis juliflora pollen allergens and showed the binding of allergens with reaginic antibody and its regulation in guinea pigs.

  11. Food Allergen Labeling: A Latin American Approach.

    Science.gov (United States)

    Lopez, Maria Cristina

    2018-01-01

    Food allergy is a public health concern almost all over the world. Although most of the countries that regulate the declaration of allergens in prepackaged foods include the list recommended by the Codex Alimentarius, some countries have added other allergens to this list due to prevalence data and regional incidence, whereas others have incorporated exceptions for some products derived from allergenic foods. Within this context, the situation in Latin America regarding these regulations is diverse. Data about prevalence of food hypersensitivity are very limited in the region. The countries that have established regulations are Brazil, Colombia, Costa Rica, Guatemala, Honduras, El Salvador, Nicaragua, Chile, Mexico, and Venezuela. Argentina has approved a regulation for the labeling of food allergens in November 2016. It only needs to be published in the Official Bulletin to go into effect. All countries follow the Codex list that includes latex and excludes sulfites, except Brazil. On the other hand, Argentina is the only country that includes exceptions. As for the methodologies for the detection of allergens in foods, this issue is a serious problem for both the food industry and control laboratories. Available methodologies are based mainly on commercial ELISA kits; currently, there are no Latin American companies that produce them, so ELISA kits are expensive and their acquisition is complicated. There is an initiative in Argentina to address all these gaps in the region through the Platform of Food Allergens (PFA), a nonprofit organization that integrates health professionals, patients, representatives of the food industry, government, and scientists. The different actions carried out by the PFA have made it possible to contact different scientific groups from other Latin American countries in order to expand this initiative and thereby promote and strengthen both public and private capacities in the region.

  12. Current challenges facing the assessment of the allergenic capacity of food allergens in animal models

    DEFF Research Database (Denmark)

    Bøgh, Katrine Lindholm; van Bilsen, Jolanda; Głogowski, Robert

    2016-01-01

    of novel food proteins. There is no doubt that robust and reliable animal models for the identification and characterization of food allergens would be valuable tools for safety assessment. However, although various animal models have been proposed for this purpose, to date, none have been formally...... validated as predictive and none are currently suitable to test the allergenic potential of new foods. Here, the design of various animal models are reviewed, including among others considerations of species and strain, diet, route of administration, dose and formulation of the test protein, relevant...

  13. Identification of Lilial as a fragrance sensitizer in a perfume by bioassay-guided chemical fractionation and structure-activity relationships

    DEFF Research Database (Denmark)

    Arnau, E G; Andersen, Klaus Ejner; Bruze, M

    2000-01-01

    Fragrance materials are among the most common causes of allergic contact dermatitis. The aim of this study was to identify in a perfume fragrance allergens not included in the fragrance mix, by use of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships...... (SARs). The basis for the investigation was a 45-year-old woman allergic to her own perfume. She had a negative patch test to the fragrance mix and agreed to participate in the study. Chemical fractionation of the perfume concentrate was used for repeated patch testing and/or repeated open application......" in their chemical structure, indicating an ability to modify skin proteins and thus behave as a skin sensitizer, were tested on the patient. The patient reacted positively to the synthetic fragrance p-t-butyl-alpha-methylhydrocinnamic aldehyde (Lilial), a widely used fragrance compound not present in the fragrance...

  14. Food allergy in breastfeeding babies. Hidden allergens in human milk.

    Science.gov (United States)

    Martín-Muñoz, M F; Pineda, F; García Parrado, G; Guillén, D; Rivero, D; Belver, T; Quirce, S

    2016-07-01

    Food allergy is a rare disorder among breastfeeding babies. Our aim was to identify responsible allergens in human milk. We studied babies developing allergic symptoms at the time they were breastfeeding. Skin prick tests (SPT) were performed with breast milk and food allergens. Specific IgE was assessed and IgE Immunoblotting experiments with breast milk were carried out to identify food allergens. Clinical evolution was evaluated after a maternal free diet. Five babies had confirmed breast milk allergy. Peanut, white egg and/or cow's milk were demonstrated as the hidden responsible allergens. No baby returned to develop symptoms once mother started a free diet. Three of these babies showed tolerance to other food allergens identified in human milk. A maternal free diet should be recommended only if food allergy is confirmed in breastfed babies.

  15. Diversity of allergen exposure: implications for the efficacy of environmental control.

    Science.gov (United States)

    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.

  16. Immunochemical Characterization of Acacia Pollen Allergens and Evaluation of Cross-Reactivity Pattern with the Common Allergenic Pollens

    Science.gov (United States)

    Shamsbiranvand, Mohammad-Hosein; Khodadadi, Ali; Assarehzadegan, Mohammad-Ali; Borsi, Seyed Hamid; Amini, Akram

    2014-01-01

    Pollen from the Acacia has been reported as an important source of pollinosis in tropical and subtropical regions of the world. The aim of this study was to characterize the IgE binding protein of Acacia farnesiana pollen extract and evaluate cross-reactivity with the most allergenic pollens. In this study, pollen extract was fractionated by SDS-PAGE and the allergenic profile was determined by IgE-immunoblotting and specific ELISA using forty-two Acacia allergic patients. Potential cross-reactivity among Acacia and selected allergenic plants was evaluated with ELISA and immunoblotting inhibition experiments. There were several resolved protein fractions on SDS-PAGE which ranged from 12 to 85 kDa. Several allergenic protein bands with molecular weights approximately between 12 and 85 kDa were recognized by IgE-specific antibodies from Acacia allergic patients in the immunoblot assay. The inhibition by the Prosopis juliflora pollen extract was more than those by other pollen extracts. Moreover, the wheal diameters generated by the Acacia pollen extract were highly correlated with those of P. juliflora pollen extracts. The findings suggest that several proteins such as 15, 23, 45, and 50 kDa proteins could be used as diagnostic and therapeutic reagents for patients allergic to A. farnesiana and P. juliflora. PMID:24949020

  17. Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Sharpe, Richard A. [European Centre for Environment and Human Health, University of Exeter Medical School, Truro TR1 3HD (United Kingdom); Cocq, Kate Le [Rothamsted Research, North Wyke, Okehampton EX20 2SB (United Kingdom); Nikolaou, Vasilis [University of Exeter Medical School, The Veysey Building, Salmon Pool Lane, Exeter EX2 4SG (United Kingdom); Osborne, Nicholas J. [European Centre for Environment and Human Health, University of Exeter Medical School, Truro TR1 3HD (United Kingdom); Clinical Pharmacology and Toxicology Research Group, Discipline of Pharmacology, Sydney Medical School, The University of Sydney, NSW (Australia); Thornton, Christopher R., E-mail: c.r.thornton@exeter.ac.uk [Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter EX4 4QD (United Kingdom)

    2016-01-15

    The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature. - Highlights: • Monoclonal antibodies were used to track culturable allergenic moulds in homes. • Allergenic moulds were recovered from 82% of swabs from contaminated surfaces. • The mAbs were highly specific with 100% agreement to PCR of recovered fungi. • Improvements to energy

  18. Identifying risk factors for exposure to culturable allergenic moulds in energy efficient homes by using highly specific monoclonal antibodies

    International Nuclear Information System (INIS)

    Sharpe, Richard A.; Cocq, Kate Le; Nikolaou, Vasilis; Osborne, Nicholas J.; Thornton, Christopher R.

    2016-01-01

    The aim of this study was to determine the accuracy of monoclonal antibodies (mAbs) in identifying culturable allergenic fungi present in visible mould growth in energy efficient homes, and to identify risk factors for exposure to these known allergenic fungi. Swabs were taken from fungal contaminated surfaces and culturable yeasts and moulds isolated by using mycological culture. Soluble antigens from cultures were tested by ELISA using mAbs specific to the culturable allergenic fungi Aspergillus and Penicillium spp., Ulocladium, Alternaria, and Epicoccum spp., Cladosporium spp., Fusarium spp., and Trichoderma spp. Diagnostic accuracies of the ELISA tests were determined by sequencing of the internally transcribed spacer 1 (ITS1)-5.8S-ITS2-encoding regions of recovered fungi following ELISA. There was 100% concordance between the two methods, with ELISAs providing genus-level identity and ITS sequencing providing species-level identities (210 out of 210 tested). Species of Aspergillus/Penicillium, Cladosporium, Ulocladium/Alternaria/Epicoccum, Fusarium and Trichoderma were detected in 82% of the samples. The presence of condensation was associated with an increased risk of surfaces being contaminated by Aspergillus/Penicillium spp. and Cladosporium spp., whereas moisture within the building fabric (water ingress/rising damp) was only associated with increased risk of Aspergillus/Penicillium spp. Property type and energy efficiency levels were found to moderate the risk of indoor surfaces becoming contaminated with Aspergillus/Penicillium and Cladosporium which in turn was modified by the presence of condensation, water ingress and rising damp, consistent with previous literature. - Highlights: • Monoclonal antibodies were used to track culturable allergenic moulds in homes. • Allergenic moulds were recovered from 82% of swabs from contaminated surfaces. • The mAbs were highly specific with 100% agreement to PCR of recovered fungi. • Improvements to energy

  19. Component resolution reveals additional major allergens in patients with honeybee venom allergy.

    Science.gov (United States)

    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.

  20. An Allergen Portrait Gallery: Representative Structures and an Overview of IgE Binding Surfaces

    Directory of Open Access Journals (Sweden)

    Ovidiu Ivanciuc

    2010-10-01

    Full Text Available Recent progress in the biochemical classification and structural determination of allergens and allergen–antibody complexes has enhanced our understanding of the molecular determinants of allergenicity. Databases of allergens and their epitopes have facilitated the clustering of allergens according to their sequences and, more recently, their structures. Groups of similar sequences are identified for allergenic proteins from diverse sources, and all allergens are classified into a limited number of protein structural families. A gallery of experimental structures selected from the protein classes with the largest number of allergens demonstrate the structural diversity of the allergen universe. Further comparison of these structures and identification of areas that are different from innocuous proteins within the same protein family can be used to identify features specific to known allergens. Experimental and computational results related to the determination of IgE binding surfaces and methods to define allergen-specific motifs are highlighted.

  1. Modified clay minerals efficiency against chemical and biological warfare agents for civil human protection.

    Science.gov (United States)

    Plachá, Daniela; Rosenbergová, Kateřina; Slabotínský, Jiří; Kutláková, Kateřina Mamulová; Studentová, Soňa; Martynková, Gražyna Simha

    2014-04-30

    Sorption efficiencies of modified montmorillonite and vermiculite of their mono ionic Na and organic HDTMA and HDP forms were studied against chemical and biological warfare agents such as yperite and selected bacterial strains. Yperite interactions with modified clay minerals were observed through its capture in low-density polyethylene foil-modified clay composites by measuring yperite gas permeation with using chemical indication and gas chromatography methods. The antibacterial activities of synthetized organoclays were tested against selected Gram-positive and Gram-negative bacterial species in minimum inhibitory concentration tests. The obtained results showed a positive influence of modified clay minerals on the significant yperite breakthrough-time increase. The most effective material was the polyethylene-Na form montmorillonite, while the polyethylene-Na form vermiculite showed the lowest efficiency. With increasing organic cations loading in the interlayer space the montmorillonite efficiency decreased, and in the case of vermiculite an opposite effect was observed. Generally the modified montmorillonites were more effective than modified vermiculites. The HDP cations seem to be more effective compare to the HDTMA. The antibacterial activity tests confirmed efficiency of all organically modified clay minerals against Gram-positive bacteria. The confirmation of antibacterial activity against Y. pestis, plague bacteria, is the most interesting result of this part of the study. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Glycoproteomic analysis of seven major allergenic proteins reveals novel post-translational modifications

    DEFF Research Database (Denmark)

    Halim, Adnan; Carlsson, Michael C; Mathiesen, Caroline Benedicte K

    2015-01-01

    Allergenic proteins such as grass pollen and house dust mite (HDM) proteins are known to trigger hypersensitivity reactions of the immune system, leading to what is commonly known as allergy. Key allergenic proteins including sequence variants have been identified but characterization of their post...... allergens. Moreover, we identified more complex glycan structures than previously reported on the major grass pollen group 1 and 5 allergens, implicating important roles for carbohydrates in allergen recognition and response by the immune system. The new findings are important for understanding basic...

  3. Screening and identification of putative allergens in berry fruits of the Rosaceae family: technical challenges.

    Science.gov (United States)

    Marzban, Gorji; Maghuly, Fatemeh; Herndl, Anita; Katinger, Hermann; Laimer, Margit

    2008-01-01

    Cross-reactive proteins in small fruits of the Rosaceae family like strawberry, raspberry and blackberry revealed an unexpected complex IgE-reactivity pattern. Several copies of PR-10 and PR-14 proteins were detected by Southern blots in strawberry, raspberry and blackberry. In raspberry, the highest similarity at the DNA level for PR-10 and PR-14 (Rub i 1 and Rub i 3) was detected to strawberry sequences of Fra a 1 and Fra a 3. At the protein level, Rub i 1 and Rub i 3 showed more than 70% identity with homologous proteins of rosaceous fruits. Furthermore, raspberries contained additional putative allergens, e.g. class III acidic chitinases and cyclophilins. Blackberries were shown to share at least two well-known major fruit allergens with other rosaceous fruits, namely PR-10s and PR-14s homologous proteins. However the IgE-reactive proteins of small fruits are still not extensively investigated. The main challenges in studying small fruit allergens are the complexity of the fruit matrix, the diversity of physico-chemical properties of fruit proteins, the lack of appropriate protein extraction procedures and the missing information about the influence of processing treatments on food components.

  4. Photoelectrocatalytic reduction of CO2 into chemicals using Pt-modified reduced graphene oxide combined with Pt-modified TiO2 nanotubes.

    Science.gov (United States)

    Cheng, Jun; Zhang, Meng; Wu, Gai; Wang, Xin; Zhou, Junhu; Cen, Kefa

    2014-06-17

    The photoelectrocatalytic (PEC) reduction of CO2 into high-value chemicals is beneficial in alleviating global warming and advancing a low-carbon economy. In this work, Pt-modified reduced graphene oxide (Pt-RGO) and Pt-modified TiO2 nanotubes (Pt-TNT) were combined as cathode and photoanode catalysts, respectively, to form a PEC reactor for converting CO2 into valuable chemicals. XRD, XPS, TEM, AFM, and SEM were employed to characterize the microstructures of the Pt-RGO and Pt-TNT catalysts. Reduction products, such as C2H5OH and CH3COOH, were obtained from CO2 under band gap illumination and biased voltage. A combined liquid product generation rate (CH3OH, C2H5OH, HCOOH, and CH3COOH) of approximately 600 nmol/(h·cm(2)) was observed. Carbon atom conversion rate reached 1,130 nmol/(h·cm(2)), which were much higher than those achieved using Pt-modified carbon nanotubes and platinum carbon as cathode catalysts.

  5. Immunological and physical properties of allergen solutions. Effects of nebulization

    DEFF Research Database (Denmark)

    Frølund, L; Poulsen, L K; Heinig, J H

    1991-01-01

    activity was measured by IgG4 RAST inhibition technique and allergen quality was analysed by crossed immunoelectrophoresis (CIE). The distribution of particle sizes of aerosols of different allergen solutions was determined by a TSI Aerodynamic Particle Sizer. A significant difference (P less than 0.......05) in allergen activity was found between the AD and H2O diluents before and after using a Sandoz nebulizer and a Wright nebulizer equipped with a small chamber. This suggested greater allergen activity in AD-diluted solutions, and the pattern was repeated with the other two nebulizers, but was not statistically...

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

    Science.gov (United States)

    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.

  7. Responsiveness of the major birch allergen Bet v 1 scaffold to the gastric environment: Impact on structure and allergenic activity

    DEFF Research Database (Denmark)

    Sancho, Ana I; Wangorsch, Andrea; Jensen, Bettina M

    2011-01-01

    Four Bet v 1 homologous food allergens from celeriac (rApi g 1), apple (rMal d 1), peach (rPru p 1) and hazelnut (rCor a 1), were used to probe the structural responsiveness of the Bet v 1 scaffold to gastric digestion conditions and its impact on allergenicity....

  8. A personalized food allergen testing platform on a cellphone.

    Science.gov (United States)

    Coskun, Ahmet F; Wong, Justin; Khodadadi, Delaram; Nagi, Richie; Tey, Andrew; Ozcan, Aydogan

    2013-02-21

    We demonstrate a personalized food allergen testing platform, termed iTube, running on a cellphone that images and automatically analyses colorimetric assays performed in test tubes toward sensitive and specific detection of allergens in food samples. This cost-effective and compact iTube attachment, weighing approximately 40 grams, is mechanically installed on the existing camera unit of a cellphone, where the test and control tubes are inserted from the side and are vertically illuminated by two separate light-emitting-diodes. The illumination light is absorbed by the allergen assay, which is activated within the tubes, causing an intensity change in the acquired images by the cellphone camera. These transmission images of the sample and control tubes are digitally processed within 1 s using a smart application running on the same cellphone for detection and quantification of allergen contamination in food products. We evaluated the performance of this cellphone-based iTube platform using different types of commercially available cookies, where the existence of peanuts was accurately quantified after a sample preparation and incubation time of ~20 min per test. This automated and cost-effective personalized food allergen testing tool running on cellphones can also permit uploading of test results to secure servers to create personal and/or public spatio-temporal allergen maps, which can be useful for public health in various settings.

  9. 21 CFR 680.2 - Manufacture of Allergenic Products.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Manufacture of Allergenic Products. 680.2 Section...) BIOLOGICS ADDITIONAL STANDARDS FOR MISCELLANEOUS PRODUCTS § 680.2 Manufacture of Allergenic Products. (a...) Cultures derived from microorganisms. Culture media into which organisms are inoculated for the manufacture...

  10. Sensory and rheological properties of transgenically and chemically modified starch ingredients as evaluated in a food product model

    DEFF Research Database (Denmark)

    Ahmt, T.; Wischmann, Bente; Blennow, A.

    2004-01-01

    gels with a higher tendency to retrograde and a low freeze/thaw stability as compared to starches with shorter amylopectin chains and lower phosphorous content. The textural properties of the food product model prepared from genetically and chemically modified starches were characterised by sensory......Starches derived from five genetically modified potato lines, two chemically modified potato starches and two native starches from potato and maize were subjected to physical and chemical analyses and their functionality evaluated in a milk-based food product model. The transgenic starches were...... and rheological analyses. To clearly visualise the effects of the modifications, data was evaluated by radar plots and multiple regression analysis (chemometrics). Genetically modified potato starches with longer amylopectin chains and increased phosphorous content gave a more gelled and a shorter texture...

  11. Exotic pets are new allergenic sources: allergy to iguana.

    Science.gov (United States)

    San Miguel-Moncín, M M; Pineda, F; Río, C; Alonso, R; Tella, R; Cisteró-Bahima, A

    2006-01-01

    Although furry animals are known sources of respiratory allergy, scaly animals are assumed not to be allergenic. Exotic animals such as iguanas are becoming increasingly common pets. Nevertheless, these animals are not suspected to be allergenic. We present the case of a 42-year-old woman suffering from allergic rhinoconjunctivitis and asthma caused by a pet iguana. Clear IgE-sensitization and respiratory allergy to iguana scales is demonstrated, suggesting that scaly pets should be taken into account as possible allergenic sources.

  12. The investigation of inhalational allergen in 208 asthmatic infants and children

    International Nuclear Information System (INIS)

    Xie Yonggang; Zhang Yi; Liu Jian

    2002-01-01

    The aim of the study was to investigate the inhalational allergen in 208 asthmatic infants and children with allergen steep puncturing skin. The positive cases were 169(81.25%). There were 18 inhalational allergens in allergen steep. The positive rate of the dust acarus was 78.85%, and the dust was 35.58%, the smoke was 32.69% among the allergens. There was not any positive reaction in other allergens. There were no sexual differences in the positive rate. There was nothing with hypersusceptibility of the individual and the family. The positive rate of the infant was less than the child. There was significant difference of the positive rate in the age group (P < 0.01). The result indicated that dust acarus, air pollution or passive smoke was the quite dangerous factor in the many factors of the asthma. It was very important to strengthen the study of the infant and child prevention and cure

  13. Chemical treatment of the intra-canal dentin surface: a new approach to modify dentin hydrophobicity

    Directory of Open Access Journals (Sweden)

    Cesar GAITAN-FONSECA

    2013-01-01

    Full Text Available Objective This study evaluated the hydrophobicity of dentin surfaces that were modified through chemical silanization with octadecyltrichlorosilane (OTS. Material and Methods An in vitro experimental study was performed using 40 human permanent incisors that were divided into the following two groups: non-silanized and silanized. The specimens were pretreated and chemically modified with OTS. After the chemical modification, the dentin hydrophobicity was examined using a water contact angle measurement (WCA. The effectiveness of the modification of hydrophobicity was verified by the fluid permeability test (FPT. Results and Conclusions Statistically significant differences were found in the values of WCA and FPT between the two groups. After silanization, the hydrophobic intraradicular dentin surface exhibited in vitro properties that limit fluid penetration into the sealed root canal. This chemical treatment is a new approach for improving the sealing of the root canal system.

  14. Health economic comparison of SLIT allergen and SCIT allergoid immunotherapy in patients with seasonal grass-allergic rhinoconjunctivitis in Germany.

    Science.gov (United States)

    Verheggen, Bram G; Westerhout, Kirsten Y; Schreder, Carl H; Augustin, Matthias

    2015-01-01

    Allergoids are chemically modified allergen extracts administered to reduce allergenicity and to maintain immunogenicity. Oralair® (the 5-grass tablet) is a sublingual native grass allergen tablet for pre- and co-seasonal treatment. Based on a literature review, meta-analysis, and cost-effectiveness analysis the relative effects and costs of the 5-grass tablet versus a mix of subcutaneous allergoid compounds for grass pollen allergic rhinoconjunctivitis were assessed. A Markov model with a time horizon of nine years was used to assess the costs and effects of three-year immunotherapy treatment. Relative efficacy expressed as standardized mean differences was estimated using an indirect comparison on symptom scores extracted from available clinical trials. The Rhinitis Symptom Utility Index (RSUI) was applied as a proxy to estimate utility values for symptom scores. Drug acquisition and other medical costs were derived from published sources as well as estimates for resource use, immunotherapy persistence, and occurrence of asthma. The analysis was executed from the German payer's perspective, which includes payments of the Statutory Health Insurance (SHI) and additional payments by insurants. Comprehensive deterministic and probabilistic sensitivity analyses and different scenarios were performed to test the uncertainty concerning the incremental model outcomes. The applied model predicted a cost-utility ratio of the 5-grass tablet versus a market mix of injectable allergoid products of € 12,593 per QALY in the base case analysis. Predicted incremental costs and QALYs were € 458 (95% confidence interval, CI: € 220; € 739) and 0.036 (95% CI: 0.002; 0.078), respectively. Compared to the allergoid mix the probability of the 5-grass tablet being the most cost-effective treatment option was predicted to be 76% at a willingness-to-pay threshold of € 20,000. The results were most sensitive to changes in efficacy estimates, duration of the pollen season, and

  15. Consumer Preferences for Written and Oral Information about Allergens When Eating Out.

    Science.gov (United States)

    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.

  16. Cow allergen (Bos d2) and endotoxin concentrations are higher in the settled dust of homes proximate to industrial-scale dairy operations.

    Science.gov (United States)

    Williams, D' Ann L; McCormack, Meredith C; Matsui, Elizabeth C; Diette, Gregory B; McKenzie, Shawn E; Geyh, Alison S; Breysse, Patrick N

    2016-01-01

    Airborne contaminants produced by industrial agricultural facilities contain chemical and biological compounds that can impact the health of residents living in close proximity. Settled dust can be a reservoir for these contaminants and can influence long-term exposures. In this study, we sampled the indoor- and outdoor-settled dust from 40 homes that varied in proximity to industrial-scale dairies (ISD; industrial-scale dairy, a term used in this paper to describe a large dairy farm and adjacent waste sprayfields, concentrated animal feeding operation or animal feeding operation, that uses industrial processes) in the Yakima Valley, Washington. We analyzed settled dust samples for cow allergen (Bos d2, a cow allergen associated with dander, hair, sweat and urine, it is a member of the lipocalin family of allergens associated with mammals), mouse allergen (Mus m1; major mouse allergen, a mouse urinary allergen, in the lipocalin family), dust mite allergens (Der p1 (Dermatophagoides pteronissinus 1) and Der f1 (Dermatophagoides farinae 1)), and endotoxin (a component of the cell walls of gram negative bacteria, lipopolysaccharide, which can be found in air and dust and can produce a strong inflammatory response). A concentration gradient was observed for Bos d2 and endotoxin measured in outdoor-settled dust samples based on proximity to ISD. Indoor-settled dust concentrations of Bos d2 and endotoxin were also highest in proximal homes. While the associated health effects of exposure to cow allergen in settled dust is unknown, endotoxin at concentrations observed in these proximal homes (100 EU/mg) has been associated with increased negative respiratory health effects. These findings document that biological contaminants emitted from ISDs are elevated in indoor- and outdoor-settled dust samples at homes close to these facilities and extend to as much as three miles (4.8 km) away.

  17. [Allergens used in skin tests in Mexico].

    Science.gov (United States)

    Larenas Linnemann, Désirée; Arias Cruz, Alfredo; Guidos Fogelbach, Guillermo Arturo; Cid del Prado, Mari Lou

    2009-01-01

    Immunotherapy is the only recognized causal treatment for allergies. It is prepared on an individual basis, based on the patient's clinical history and the result of the skin prick test (SPT). An adequate composition of the allergens with which to test the patient is crucial for an optimal diagnosis. To know allergens used in tests in allergy practices in Mexico. A national survey among all members of the Colegio Mexicano de Inmunología Clínica y Alergia (CMICA) and of the Colegio Mexicano de Pediatras Especialistas en Inmunología Clínica y Alergia (COMPEDIA) was carried out. In a second phase respondents were asked to send in the composition of a routine SPT in their clinic. The results are presented descriptively and the frequency is calculated by which certain allergen is tested in the interviewed practices. A survey response rate of 61 (17%) was obtained and 54% showed their SPT content. Weeds' representation in the SPT seems adequate; Atriplex is tested in all allergy practices. Some trees that show cross-reactivity might be eliminated from the SPT, but 20% doesn't test for Cynodon nor Holcus, and 25% doesn't for important allergens as cat, dog and cockroach. House dust and tobacco are still tested with certain frequency. The selection of which allergens to test in a SPT is based on multiple data, that change continuously with new investigations and discoveries. Our specialty is the most indicated--and obligated--to adjust constantly to these changes to have the best diagnostic tool to detect specific allergies.

  18. Environmental allergens in patients with allergic rhinitis

    International Nuclear Information System (INIS)

    Anwar, M.S.; Bokhari, S.R.

    2002-01-01

    Objective: to find out the common environmental allergens responsible for sensitivity in patients with allergic rhinitis. Design: Descriptive cross sectional study. Place and Duration of Study: A local allergy clinic in an urban area of Lahore during the year 2000-2001. Subjects and Methods: Eighty patients with allergic rhinitis irrespective of age and sex were studied. These cases were selected on the basis of symptoms like sneezing, itching, watery nasal discharge and eosinophilia in nasal secretions. Forty matched healthy subjects as controls were also studied. Allergy test was performed on all the subjects by skin prick test to determine sensitivity to common environmental allergens using Bencard (England) allergy kit. Results: common environmental allergens responsible for sensitivity in allergic rhinitis patients were house dust (82.5 %), house dust mites (73.7%), mixed threshing (80%), straw dust (58.7%, hay dust (63.7%), mixed feathers (45%), cat fur (57.5%), cotton flock (56.2%), tree pollens (45%) and grass pollens (48.7%). Sensitivity to these allergens was observed in significantly higher (P<0.01) percentage of allergic rhinitis patients as compared with control subjects. Sensitivity to house dust, house dust mites and cat fur was of severe degree in majority of allergic rhinitis patients. While sensitivity to mixed threshing, straw dust, hay dust and mixed feathers was of moderate to severe degree in majority of these patients. Conclusion: Skin prick tests provide an effective and definitive mean to find out sensitivity to different allergens in cases with allergic rhinitis. Based on these findings, the physician can manage these patients in better way. (author)

  19. Immunological mechanisms of sublingual allergen-specific immunotherapy.

    Science.gov (United States)

    Novak, Natalija; Bieber, T; Allam, J-P

    2011-06-01

    Within the last 100 years of allergen-specific immunotherapy, many clinical and scientific efforts have been made to establish alternative noninvasive allergen application strategies. Thus, intra-oral allergen delivery to the sublingual mucosa has been proven to be safe and effective. As a consequence, to date, sublingual immunotherapy (SLIT) is widely accepted by most allergists as an alternative to conventional subcutaneous immunotherapy. Although immunological mechanisms remain to be elucidated in detail, several studies in mice and humans within recent years provided deeper insights into local as well as systemic immunological features in response to SLIT. First of all, it was shown that the target organ, the oral mucosa, harbours a sophisticated immunological network as an important prerequisite for SLIT, which contains among other cells, local antigen-presenting cells (APC), such as dendritic cells (DCs), with a constitutive disposition to enforce tolerogenic mechanisms. Further on, basic research on local DCs within the oral mucosa gave rise to possible alternative strategies to deliver the allergens to other mucosal regions than sublingual tissue, such as the vestibulum oris. Moreover, characterization of oral DCs led to the identification of target structures for both allergens as well as adjuvants, which could be applied during SLIT. Altogether, SLIT came a long way since its very beginning in the last century and some, but not all questions about SLIT could be answered so far. However, recent research efforts as well as clinical approaches paved the way for another exciting 100 years of SLIT. © 2011 John Wiley & Sons A/S.

  20. Risk assessment of allergen metals in cosmetic products.

    Science.gov (United States)

    Sipahi, Hande; Charehsaz, Mohammad; Güngör, Zerrin; Erdem, Onur; Soykut, Buğra; Akay, Cemal; Aydin, Ahmet

    2015-01-01

    Cosmetics are one of the most common reasons for hospital referrals with allergic contact dermatitis. Because of the increased use of cosmetics within the population and an increase in allergy cases, monitoring of heavy metals, especially allergen metals, is crucial. The aim of this study was to investigate the concentration of allergen metals, nickel (Ni), cobalt (Co), and chromium (Cr), in the most commonly used cosmetic products including mascara, eyeliner, eye shadow, lipstick, and nail polish. In addition, for safety assessment of cosmetic products, margin of safety of the metals was evaluated. Forty-eight makeup products were purchased randomly from local markets and large cosmetic stores in Istanbul, Turkey, and an atomic absorption spectrometer was used for metal content determination. Risk assessment of the investigated cosmetic products was performed by calculating the systemic exposure dosage (SED) using Scientific Committee on Consumer Safety guideline. According to the results of this investigation in all the samples tested, at least two of the allergen metals, Ni and/or Co and/or Cr were detected. Moreover, 97% of the Ni-detected products, 96% of Cr- and 54% of Co-detected products, contained over 1 μg/g of this metals, which is the suggested ultimate target value for sensitive population and thereby can be considered as the possible allergen. On the basis of the results of this study, SED of the metals was negligible; however, contact dermatitis caused by cosmetics is most probably due to the allergen metal content of the products. In conclusion, to assess the safety of the finished products, postmarketing vigilance and routine monitoring of allergen metals are very important to protect public health.

  1. Chemically modified cellulose paper as a thin film microextraction phase.

    Science.gov (United States)

    Saraji, Mohammad; Farajmand, Bahman

    2013-11-01

    In this paper, chemically modified cellulose paper was introduced as a novel extracting phase for thin film microextraction (TFME). Different reagents (Octadecyltrichlorosilane, diphenyldichlorosilane, cyclohexyl isocyanate and phenyl isocyanate) were used to modify the cellulose papers. The modified papers were evaluated as a sorbent for the extraction of some synthetic and natural estrogenic hormones (17α-ethynylestradiol, estriol and estradiol) from aqueous samples. Liquid chromatography-fluorescence detection was used for the quantification of the extracted compounds. The cellulose paper modified with phenyl isocyanate showed the best affinity to the target compounds. TEME parameters such as desorption condition, shaking rate, sample ionic strength and extraction time were investigated and optimized. Limit of detections were between 0.05 and 0.23μgL(-1) and relative standard deviations were less than 11.1% under the optimized condition. The calibration curves were obtained in the range of 0.2-100μgL(-1) with a good linearity (r(2)>0.9935). Wastewater, human urine, pool and river water samples were studied as real samples for the evaluation of the method. Relative recoveries were found to be between 75% and 101%. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Chemically modified oligonucleotides with efficient RNase H response

    DEFF Research Database (Denmark)

    Vester, Birte; Boel, Anne Marie; Lobedanz, Sune

    2008-01-01

    Ten different chemically modified nucleosides were incorporated into short DNA strands (chimeric oligonucleotides ON3-ON12 and ON15-ON24) and then tested for their capacity to mediate RNAse H cleavage of the complementary RNA strand. The modifications were placed at two central positions directly...... in the RNase H cleaving region. The RNA strand of duplexes with ON3, ON5 and ON12 were cleaved more efficiently than the RNA strand of the DNA:RNA control duplex. There seems to be no correlation between the thermal stability between the duplexes and RNase H cleavage....

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

    Science.gov (United States)

    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.

  4. Production of Recombinant Peanut Allergen Ara h 2 using Lactococcus lactis

    Directory of Open Access Journals (Sweden)

    Frøkiær Hanne

    2007-08-01

    Full Text Available Abstract Background Natural allergen sources can supply large quantities of authentic allergen mixtures for use as immunotherapeutics. However, such extracts are complex, difficult to define, vary from batch to batch, which may lead to unpredictable efficacy and/or unacceptable levels of side effects. The use of recombinant expression systems for allergen production can alleviate some of these issues. Several allergens have been tested in high-level expression systems and in most cases show immunereactivity comparable to their natural counterparts. The gram positive lactic acid bacterium Lactococcus lactis is an attractive microorganism for use in the production of protein therapeutics. L. lactis is considered food grade, free of endotoxins, and is able to secrete the heterologous product together with few other native proteins. Hypersensitivity to peanut represents a serious allergic problem. Some of the major allergens in peanut have been described. However, for therapeutic usage more information about the individual allergenic components is needed. In this paper we report recombinant production of the Ara h 2 peanut allergen using L. lactis. Results A synthetic ara h 2 gene was cloned into an L. lactis expression plasmid containing the P170 promoter and the SP310mut2 signal sequence. Flask cultures grown overnight showed secretion of the 17 kDa Ara h 2 protein. A batch fermentation resulted in 40 mg/L recombinant Ara h 2. Purification of Ara h 2 from the culture supernatant was done by hydrophobic exclusion and size separation. Mass spectrometry and N-terminal analysis showed a recombinant Ara h 2 of full length and correctly processed by the signal peptidase. The immunological activity of recombinant Ara h 2 was analysed by ELISA using antibodies specific for native Ara h 2. The recombinant Ara h 2 showed comparable immunereactivity to that of native Ara h 2. Conclusion Recombinant production of Ara h 2 using L. lactis can offer high yields

  5. Nanoallergens: A multivalent platform for studying and evaluating potency of allergen epitopes in cellular degranulation

    Science.gov (United States)

    Deak, Peter E; Vrabel, Maura R; Pizzuti, Vincenzo J; Kiziltepe, Tanyel

    2016-01-01

    Degranulation caused by type I hypersensitivity (allergies) is a complex biophysical process, and available experimental models for studying relevant immunoglobulin E binding epitopes on allergen proteins lack the ability to adequately evaluate, rank, and associate these epitopes individually and with each other. In this study, we propose a new allergy model system for studying potential allergen epitopes using nanoallergens, liposomes modified to effectively display IgE binding epitopes/haptens. By utilizing the covalently conjugated lipid tails on two hapten molecules (dinitrophenol and dansyl), hapten molecules were successfully incorporated into liposomes with high precision to form nanoallergens. Nanoallergens, with precisely controlled high-particle valency, can trigger degranulation with much greater sensitivity than commonly used bovine serum albumin conjugates. In rat basophil leukemia cell experiments, nanoallergens with only 2% hapten loading were able to trigger degranulation in vitro at concentrations as low as 10 pM. Additionally, unlike bovine serum albumin-hapten conjugates, nanoallergens allow exact control over particle size and valency. By varying the nanoallergen parameters such as size, valency, monovalent affinity of hapten, and specific IgE ratios, we exposed the importance of these variables on degranulation intensity while demonstrating nanoallergens’ potential for evaluating both high- and low-affinity epitopes. The data presented in this article establish nanoallergen platform as a reliable and versatile allergy model to study and evaluate allergen epitopes in mast cell degranulation. PMID:27188517

  6. Current challenges facing the assessment of the allergenic capacity of food allergens in animal models.

    Science.gov (United States)

    Bøgh, Katrine Lindholm; van Bilsen, Jolanda; Głogowski, Robert; López-Expósito, Iván; Bouchaud, Grégory; Blanchard, Carine; Bodinier, Marie; Smit, Joost; Pieters, Raymond; Bastiaan-Net, Shanna; de Wit, Nicole; Untersmayr, Eva; Adel-Patient, Karine; Knippels, Leon; Epstein, Michelle M; Noti, Mario; Nygaard, Unni Cecilie; Kimber, Ian; Verhoeckx, Kitty; O'Mahony, Liam

    2016-01-01

    Food allergy is a major health problem of increasing concern. The insufficiency of protein sources for human nutrition in a world with a growing population is also a significant problem. The introduction of new protein sources into the diet, such as newly developed innovative foods or foods produced using new technologies and production processes, insects, algae, duckweed, or agricultural products from third countries, creates the opportunity for development of new food allergies, and this in turn has driven the need to develop test methods capable of characterizing the allergenic potential of novel food proteins. There is no doubt that robust and reliable animal models for the identification and characterization of food allergens would be valuable tools for safety assessment. However, although various animal models have been proposed for this purpose, to date, none have been formally validated as predictive and none are currently suitable to test the allergenic potential of new foods. Here, the design of various animal models are reviewed, including among others considerations of species and strain, diet, route of administration, dose and formulation of the test protein, relevant controls and endpoints measured.

  7. Complete amino acid sequence of a Lolium perenne (perennial rye grass) pollen allergen, Lol p II.

    Science.gov (United States)

    Ansari, A A; Shenbagamurthi, P; Marsh, D G

    1989-07-05

    The complete amino acid sequence of a Lolium perenne (rye grass) pollen allergen, Lol p II was determined by automated Edman degradation of the protein and selected fragments. Cleavage of the protein by enzymatic and chemical techniques established an unambiguous sequence for the protein. Lol p II contains 97 amino acid residues, with a calculated molecular weight of 10,882. The protein lacks cysteine and glutamine and shows no evidence of glycosylation. Theoretical predictions by Fraga's (Fraga, S. (1982) Can. J. Chem. 60, 2606-2610) and Hopp and Woods' (Hopp, T. P., and Woods, K. R. (1981) Proc. Natl. Acad. Sci. U.S.A. 78, 3824-3828) methods indicate the presence of four hydrophilic regions, which may contribute to sequential or parts of conformational B-cell epitopes. Analysis of amphipathic regions by Berzofsky's method indicates the presence of a highly amphipathic region, which may contain, or contribute to, an Ia/T-cell epitope. This latter segment of Lol p II was found to be highly homologous with an antibody-binding segment of the major rye allergen Lol p I and may explain why immune responsiveness to both the allergens is associated with HLA-DR3.

  8. Chemical functionalization of ceramic tile surfaces by silane coupling agents: polymer modified mortar adhesion mechanism implications

    Directory of Open Access Journals (Sweden)

    Alexandra Ancelmo Piscitelli Mansur

    2008-09-01

    Full Text Available Adhesion between tiles and mortars are crucial to the stability of ceramic tile systems. From the chemical point of view, weak forces such as van der Waals forces and hydrophilic interactions are expected to be developed preferably at the tiles and polymer modified Portland cement mortar interface. The main goal of this paper was to use organosilanes as primers to modify ceramic tile hydrophilic properties to improve adhesion between ceramic tiles and polymer modified mortars. Glass tile surfaces were treated with several silane derivatives bearing specific functionalities. Contact angle measurements and Fourier Transform Infrared Spectroscopy (FTIR were used for evaluating the chemical changes on the tile surface. In addition, pull-off tests were conducted to assess the effect on adhesion properties between tile and poly(ethylene-co-vinyl acetate, EVA, modified mortar. The bond strength results have clearly shown the improvement of adherence at the tile-polymer modified mortar interface, reflecting the overall balance of silane, cement and polymer interactions.

  9. Chemically modified tetracyclines stimulate matrix metalloproteinase-s production by periodontal ligament cells

    NARCIS (Netherlands)

    Bildt, M.M.; Snoek-van Beurden, A.M.P.; Groot, J. de; El, B. van; Kuijpers-Jagtman, A.M.; Hoff, J.W. van den

    2006-01-01

    Background and Objective: The purpose of this study was to investigate the effects of chemically modified tetracyclines (CMTs) on the production of gelatinases [matrix metalloproteinase (MMP)-2 and -9] by human periodontal ligament (PDL) cells, and on the activity of recombinant gelatinases.

  10. Domestic cat allergen and allergic sensitisation in young children

    NARCIS (Netherlands)

    Chen, Chih-Mei; Gehring, Ulrike; Wickman, Magnus; Hoek, Gerard; Giovannangelo, Mariella; Nordling, Emma; Wijga, Alet; de Jongste, Johan; Pershagen, Goeran; Almqvist, Catarina; Kerkhof, Marjan; Bellander, Tom; Wichmann, H. -Erich; Brunekreef, Bert; Heinrich, Joachim

    Studies have presented conflicting associations between cat allergen exposure and sensitisation and atopic disease. We therefore investigated the association between the observed domestic cat allergen level and cat sensitisation in young children in four study populations from three European

  11. Allergenic food introduction and risk of childhood atopic diseases

    NARCIS (Netherlands)

    N.J. Elbert (Niels); J.C. Kiefte-de Jong (Jessica); R.G. Voortman (Trudy); T.E.C. Nijsten (Tamar); N.W. de Jong (Nicolette); V.W.V. Jaddoe (Vincent); J.C. de Jongste (Johan); R. Gerth van Wijk (Roy); Duijts, L. (Liesbeth); S.G.M.A. Pasmans (Suzanne)

    2017-01-01

    textabstractBackground: The role of timing and diversity of allergenic food introduction in the development of childhood allergic sensitization and atopic diseases is controversial. Objective: To examine whether timing and diversity of allergenic food introduction are associated with allergic

  12. Are neighborhood-level characteristics associated with indoor allergens in the household?

    Science.gov (United States)

    Rosenfeld, Lindsay; Rudd, Rima; Chew, Ginger L; Emmons, Karen; Acevedo-García, Dolores

    2010-02-01

    Individual home characteristics have been associated with indoor allergen exposure; however, the influence of neighborhood-level characteristics has not been well studied. We defined neighborhoods as community districts determined by the New York City Department of City Planning. We examined the relationship between neighborhood-level characteristics and the presence of dust mite (Der f 1), cat (Fel d 1), cockroach (Bla g 2), and mouse (MUP) allergens in the household. Using data from the Puerto Rican Asthma Project, a birth cohort of Puerto Rican children at risk of allergic sensitization (n = 261), we examined associations between neighborhood characteristics (percent tree canopy, asthma hospitalizations per 1,000 children, roadway length within 100 meters of buildings, serious housing code violations per 1000 rental units, poverty rates, and felony crime rates), and the presence of indoor allergens. Allergen cutpoints were used for categorical analyses and defined as follows: dust mite: >0.25 microg/g; cat: >1 microg/g; cockroach: >1 U/g; mouse: >1.6 microg/g. Serious housing code violations were statistically significantly positively associated with dust mite, cat, and mouse allergens (continuous variables), adjusting for mother's income and education, and all neighborhood-level characteristics. In multivariable logistic regression analyses, medium levels of housing code violations were associated with higher dust mite and cat allergens (1.81, 95%CI: 1.08, 3.03 and 3.10, 95%CI: 1.22, 7.92, respectively). A high level of serious housing code violations was associated with higher mouse allergen (2.04, 95%CI: 1.15, 3.62). A medium level of housing code violations was associated with higher cockroach allergen (3.30, 95%CI: 1.11, 9.78). Neighborhood-level characteristics, specifically housing code violations, appear to be related to indoor allergens, which may have implications for future research explorations and policy decisions.

  13. Genome-wide analysis of potential cross-reactive endogenous allergens in rice (Oryza sativa L.

    Directory of Open Access Journals (Sweden)

    Fang Chao Zhu

    2015-01-01

    Full Text Available The proteins in the food are the source of common allergic components to certain patients. Current lists of plant endogenous allergens were based on the medical/clinical reports as well as laboratory results. Plant genome sequences made it possible to predict and characterize the genome-wide of putative endogenous allergens in rice (Oryza sativa L.. In this work, we identified and characterized 122 candidate rice allergens including the 22 allergens in present databases. Conserved domain analysis also revealed 37 domains among rice allergens including one novel domain (histidine kinase-, DNA gyrase B-, and HSP90-like ATPase, PF13589 adding to the allergen protein database. Phylogenetic analysis of the allergens revealed the diversity among the Prolamin superfamily and DnaK protein family, respectively. Additionally, some allergens proteins clustered on the rice chromosome might suggest the molecular function during the evolution.

  14. Comparing Proteolytic Fingerprints of Antigen-Presenting Cells during Allergen Processing.

    Science.gov (United States)

    Hofer, Heidi; Weidinger, Tamara; Briza, Peter; Asam, Claudia; Wolf, Martin; Twaroch, Teresa E; Stolz, Frank; Neubauer, Angela; Dall, Elfriede; Hammerl, Peter; Jacquet, Alain; Wallner, Michael

    2017-06-08

    Endolysosomal processing has a critical influence on immunogenicity as well as immune polarization of protein antigens. In industrialized countries, allergies affect around 25% of the population. For the rational design of protein-based allergy therapeutics for immunotherapy, a good knowledge of T cell-reactive regions on allergens is required. Thus, we sought to analyze endolysosomal degradation patterns of inhalant allergens. Four major allergens from ragweed, birch, as well as house dust mites were produced as recombinant proteins. Endolysosomal proteases were purified by differential centrifugation from dendritic cells, macrophages, and B cells, and combined with allergens for proteolytic processing. Thereafter, endolysosomal proteolysis was monitored by protein gel electrophoresis and mass spectrometry. We found that the overall proteolytic activity of specific endolysosomal fractions differed substantially, whereas the degradation patterns of the four model allergens obtained with the different proteases were extremely similar. Moreover, previously identified T cell epitopes were assigned to endolysosomal peptides and indeed showed a good overlap with known T cell epitopes for all four candidate allergens. Thus, we propose that the degradome assay can be used as a predictor to determine antigenic peptides as potential T cell epitopes, which will help in the rational design of protein-based allergy vaccine candidates.

  15. Adhesion mapping of chemically modified and poly(ethylene oxide)-grafted glass surfaces

    OpenAIRE

    Jogikalmath, G.; Stuart, J.K.; Pungor, A.; Hlady, V.

    1999-01-01

    Two-dimensional mapping of the adhesion pull-off forces was used to study the origin of surface heterogeneity in the grafted poly(ethylene oxide) (PEO) layer. The variance of the pull-off forces measured over the μm-sized regions after each chemical step of modifying glass surfaces was taken to be a measure of the surface chemical heterogeneity. The attachment of γ-glycidoxypropyltrimethoxy silane (GPS) to glass decreased the pull-off forces relative to the clean glass and made the surface mo...

  16. Dependence of radioprotective effect of chemical modifying agents on their intracellular concentrations

    International Nuclear Information System (INIS)

    Eidus, L.K.; Korystov, Y.N.; Kublik, L.N.; Vexler, A.M.

    1982-01-01

    Regularities of the radioprotective effect of chemical modifying agents cysteamine, caffeine benzoate, thioglycolic acid, and caffeine, all weak electrolytes, have been studied in cultured Chinese hamster cells. Efficiency of protection is shown to be dependent on pH and concentrations of the drug inside the cells and in the medium. Based on the theory of the dissociation of weak electrolytes and their distribution between the cells and the medium a strong correlation between the efficiency of modification of the radiation response and intracellular concentration of a modifying agent is shown. (author)

  17. Experimental approaches to predict allergenic potential of novel food

    DEFF Research Database (Denmark)

    Madsen, Charlotte Bernhard; Kroghsbo, Stine; Bøgh, Katrine Lindholm

    2013-01-01

    ’t know under what circumstances oral tolerance develops. With all these unanswered questions, it is a big challenge to designan animal model that, with relatively few animals, is able to predict if a food protein is a potential allergen. An even larger challenge is to predict its potency, a prerequisite...... for risk evaluation.Attempts have been made to rank proteins according to their allergenic potency based on the magnitude of the IgE response in experimental animals. This ranking has not included abundance as a parameter. We may be able to predict potential allergenicity i.e. hazard but our lack......There are many unanswered questions relating to food allergy sensitization in humans. We don’t know under what circumstances sensitization takes place i.e. route (oral, dermal, respiratory), age, dose, frequencyof exposure, infection or by-stander effect of other allergens. In addition we don...

  18. Identification of novel allergens of Aspergillus fumigatus using immunoproteomics approach.

    Science.gov (United States)

    Gautam, P; Sundaram, C S; Madan, T; Gade, W N; Shah, A; Sirdeshmukh, R; Sarma, P U

    2007-08-01

    Approximately 20% of the world's asthmatics are suffering from Aspergillus fumigatus (Afu)-induced allergies. The characterization of specific IgE-inducing allergens in allergic aspergillosis patients is fundamental for clinical diagnosis and for immunotherapy. Immunoproteomics combined with mass spectrometric analysis was used to identify proteins of third-week culture filtrate (3wcf) potentially responsible for Afu-specific IgE immunoreactivity, using pooled sera from Afu-sensitized asthmatics. Their allergenic potential was also tested against patients with allergic bronchopulmonary aspergillosis (ABPA), by two-dimensional (2-D) gel electrophoresis immunoblotting of 3wcf proteins with individual sera from such patients. This helped us to establish a set of candidate allergens, which could be explored further for diagnostic application in allergic aspergillosis asthmatics including ABPA. Peptide mass fingerprint using matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS) and/or de novo sequencing by MS/MS analysis of the protein spots from 2-D gels led to the identification of a total of 16 allergens of Afu. Eleven of them are being reported as allergens for the first time and five had been reported earlier. Putative isoforms of the proteins Asp f 13 and chitosanase have been observed for the first time. When studied for reactivity of these proteins among patients with ABPA using their individual sera, these patients exhibited sensitization although the pattern was varying. Taken together, these proteins could thus be considered as potential allergens even among patients with ABPA. Three of these proteins viz. the hypothetical protein (# spot no. 5), extracellular arabinase (# spot no. 6) and chitosanase (# spot no. 11) could be major allergens with specific IgE immunoreactivity with six out of eight patients' sera. The immunoproteomic approach applied to the analysis of culture filtrate proteins resulted in the

  19. Allergen-induced changes in airway responsiveness are related to baseline airway responsiveness

    NARCIS (Netherlands)

    deBruinWeller, MS; Weller, FR; RijssenbeekNouwens, LHM; Jansen, HM; deMonchy, JGR

    In the literature, bronchial allergen challenge is usually reported to result in an increase in histamine-induced airway responsiveness (AR). The present study investigated the relation between baseline AR and allergen-induced changes in AR. The effect of allergen challenge on AR was investigated in

  20. Allergen immunotherapy for allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Nurmatov, Ulugbek; Dhami, Sangeeta; Arasi, Stefania

    2017-01-01

    Background: The European Academy of Allergy and Clinical Immunology (EAACI) is developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis (ARC). To inform the development of recommendations, we sought to critically assess the systematic review evidence on the effective......Background: The European Academy of Allergy and Clinical Immunology (EAACI) is developing Guidelines on Allergen Immunotherapy (AIT) for Allergic Rhinoconjunctivitis (ARC). To inform the development of recommendations, we sought to critically assess the systematic review evidence...... of these were judged to be of high, five moderate and three low quality. These reviews suggested that, in carefully selected patients, subcutaneous (SCIT) and sublingual (SLIT) immunotherapy resulted in significant reductions in symptom scores and medication requirements. Serious adverse outcomes were rare...

  1. The association of the original OSHA chemical hazard communication standard with reductions in acute work injuries/illnesses in private industry and the industrial releases of chemical carcinogens.

    Science.gov (United States)

    Oleinick, Arthur

    2014-02-01

    OSHA predicted the original chemical Hazard Communication Standard (HCS) would cumulatively reduce the lost workday acute injury/illness rate for exposure events by 20% over 20 years and reduce exposure to chemical carcinogens. JoinPoint trend software identified changes in the rate of change of BLS rates for days away from work for acute injuries/illnesses during 1992-2009 for manufacturing and nonmanufacturing industries for both chemical, noxious or allergenic injury exposure events and All other exposure events. The annual percent change in the rates was used to adjust observed numbers of cases to estimate their association with the standard. A case-control study of EPA's Toxic Release Inventory 1988-2009 data compared carcinogen and non-carcinogens' releases. The study estimates that the HCS was associated with a reduction in the number of acute injuries/illnesses due to chemical injury exposure events over the background rate in the range 107,569-459,395 (Hudson method/modified BIC model) depending on whether the HCS is treated as a marginal or sole factor in the decrease. Carcinogen releases have declined at a substantially faster rate than control non-carcinogens. The previous HCS standard was associated with significant reductions in chemical event acute injuries/illnesses and chemical carcinogen exposures. © 2013 Wiley Periodicals, Inc.

  2. Altering allergenicity of cow's milk by food processing for applications in infant formula.

    Science.gov (United States)

    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.

  3. Fractionation and immunochemical characterization of Prosopis juliflora pollen allergen.

    Science.gov (United States)

    Thakur, I S

    1986-12-01

    Prosopis juliflora pollen grain crude extract gave six different molecular weight fractions varied from 81,000 to 13,000 dalton on Sephadex G-100 gel filtration. The purity of fractions of Prosopis juliflora pollen extract were checked by polyacrylamide gel electrophoresis. The fraction had an molecular weight 20,000 dalton showed four absorption maxima whereas other fractions had single absorption maxima. Allergenic activity and nature of allergens were evaluated by in vitro Radioallergosorbent test and in vivo Passive Cutaneous Anaphylaxis test. All these tests indicated that most allergenic fractions were in the 20,000 molecular weight.

  4. Consumer-friendly food allergen detection: moving towards smartphone-based immunoassays.

    Science.gov (United States)

    Ross, Georgina M S; Bremer, Monique G E G; Nielen, Michel W F

    2018-03-26

    In this critical review, we provide a comprehensive overview of immunochemical food allergen assays and detectors in the context of their user-friendliness, through their connection to smartphones. Smartphone-based analysis is centered around citizen science, putting analysis into the hands of the consumer. Food allergies represent a significant worldwide health concern and consumers should be able to analyze their foods, whenever and wherever they are, for allergen presence. Owing to the need for a scientific background, traditional laboratory-based detection methods are generally unsuitable for the consumer. Therefore, it is important to develop simple, safe, and rapid assays that can be linked with smartphones as detectors to improve user accessibility. Smartphones make excellent detection systems because of their cameras, embedded flash functions, portability, connectivity, and affordability. Therefore, this review has summarized traditional laboratory-based methods for food allergen detection such as enzyme-linked-immunosorbent assay, flow cytometry, and surface plasmon resonance, and the potential to modernize these methods by interfacing them with a smartphone readout system, based on the aforementioned smartphone characteristics. This is the first review focusing on smartphone-based food-allergen detection methods designed with the intention of being consumer-friendly. Graphical abstract A smartphone-based food allergen detection system in three easy steps (1) sample preparation, (2) allergen detection on a smartphone using antibodies, which then transmits the data wirelessly, (3) analytical results sent straight to smartphone.

  5. Effects of high hydrostatic pressure on the structure and potential allergenicity of the major allergen bovine β-lactoglobulin.

    Science.gov (United States)

    Meng, Xuanyi; Bai, Yuxin; Gao, Jinyan; Li, Xin; Chen, Hongbing

    2017-03-15

    Bovine β-lactoglobulin (β-Lg) is recognized as a significant milk allergen in several countries. In this study, β-Lg was isolated and treated with high hydrostatic pressure (HHP) at 100, 200, 300, 400, and 500MPa. The allergenic properties of the HHP-treated β-Lg were characterized by indirect competitive enzyme-linked immunosorbent assay with anti-β-Lg rabbit antibody and the sera of patients allergic to cows' milk. The conformation of the HHP-treated β-Lg was examined with ultraviolet absorption spectroscopy, endogenous fluorescence spectroscopy, exogenous fluorescence spectroscopy, and circular dichroism spectroscopy analyses. The results indicated that IgG binding increased with treatment pressure, and IgE binding was lowest at 200MPa and highest at 400MPa. The tertiary structure of β-Lg changed significantly after HHP, whereas the primary and secondary structures remained stable. Overall, this study suggests that the conformational changes in HHP-treated β-Lg contribute to its altered allergenicity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Household mold and dust allergens: Exposure, sensitization and childhood asthma morbidity

    International Nuclear Information System (INIS)

    Gent, Janneane F.; Kezik, Julie M.; Hill, Melissa E.; Tsai, Eling; Li, De-Wei; Leaderer, Brian P.

    2012-01-01

    Background: Few studies address concurrent exposures to common household allergens, specific allergen sensitization and childhood asthma morbidity. Objective: To identify levels of allergen exposures that trigger asthma exacerbations in sensitized individuals. Methods: We sampled homes for common indoor allergens (fungi, dust mites (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1) and cockroach (Bla g 1)) for levels associated with respiratory responses among school-aged children with asthma (N=1233) in a month-long study. Blood samples for allergy testing and samples of airborne fungi and settled dust were collected at enrollment. Symptoms and medication use were recorded on calendars. Combined effects of specific allergen sensitization and level of exposure on wheeze, persistent cough, rescue medication use and a 5-level asthma severity score were examined using ordered logistic regression. Results: Children sensitized and exposed to any Penicillium experienced increased risk of wheeze (odds ratio [OR] 2.12 95% confidence interval [CI] 1.12, 4.04), persistent cough (OR 2.01 95% CI 1.05, 3.85) and higher asthma severity score (OR 1.99 95% CI 1.06, 3.72) compared to those not sensitized or sensitized but unexposed. Children sensitized and exposed to pet allergen were at significantly increased risk of wheeze (by 39% and 53% for Fel d 1>0.12 μg/g and Can f 1>1.2 μg/g, respectively). Increased rescue medication use was significantly associated with sensitization and exposure to Der p 1>0.10 μg/g (by 47%) and Fel d 1>0.12 μg/g (by 32%). Conclusion: Asthmatic children sensitized and exposed to low levels of common household allergens Penicillium, Der p 1, Fel d 1 and Can f 1 are at significant risk for increased morbidity. - Highlights: ► Few studies address concurrent allergen exposures, sensitization and asthma morbidity. ► Children with asthma were tested for sensitivity to common indoor allergens. ► Homes were sampled for these allergens and asthma

  7. A four-step sandwich radioimmunoassay for direct selection of monoclonal antibodies to allergen molecules

    International Nuclear Information System (INIS)

    Ley, V.; Corbi, A.L.; Sanchez-Madrid, F.; Carreira, J.C.

    1985-01-01

    A 4-step radioimmunoassay has been devised for direct identification of monoclonal antibodies (MAb) directed to IgE-binding molecules. Polyvinyl chloride wells coated with purified anti-mouse kappa chain MAb (187-1) were successively incubated with: (1) MAb-containing hybridoma supernatants, (2) allergen extract, (3) allergic patients' serum pool, and (4) 125 I-labeled anti-human IgE antiserum, to detect MAb-allergen-IgE complexes. MAb to allergens from Parietaria judaica pollen and Dermatophagoides mites have been selected with this screening procedure. The affinity-purified allergen molecules competed the binding of IgE to allergen extracts coated to paper discs in a RAST inhibition assay, confirming the anti-allergen specificity of the selected MAb. This screening method is sensitive enough to allow detection of MAb directed to poorly represented allergens. (Auth.)

  8. Clinical significance identification in the of aero-allergen western Cape

    African Journals Online (AJOL)

    -allergen ... avoidance measures and the selection of patients suitable for immunotherapy. ... continuous volumetric air sampling, using a Burkard spore trap. Mould spore counts .... evidence of asthma, rhinitis and!or eczema. Drops of allergen.

  9. Crystal structure determination and analysis of 11S coconut allergen: Cocosin.

    Science.gov (United States)

    Vajravijayan, S; Nandhagopal, N; Gunasekaran, K

    2017-12-01

    Allergy is an abnormal immune response against an innocuous target. Food allergy is an adverse reaction caused by common foods most well-known being those involving peanuts. Apart from mono sensitized food allergy, cross-reactivity with other food allergens is also commonly observed. To understand the phenomenon of cross-reactivity related to immune response, three dimensional structures of the allergens and their antigenic epitopes has to be analysed in detail. The X-ray crystal structure of Cocosin, a common 11S food allergen from coconut, has been determined at 2.2Å resolution using molecular replacement technique. The monomer of 52kDa is composed of two β-jelly roll domains, one with acidic and the other with basic character. The structure shows hexameric association with two trimers facing each other. Though the overall structure of Cocosin is similar to other 11S allergens, the occurrence of experimentally determined epitopes of the peanut allergen Ara h 3 at flexible as well as variable regions could be the reason for the clinically reported result of cross-reactivity that the peanut allergic patients are not sensitized with coconut allergen. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Improving Allergen Prediction in Main Crops Using a Weighted Integrative Method.

    Science.gov (United States)

    Li, Jing; Wang, Jing; Li, Jing

    2017-12-01

    As a public health problem, food allergy is frequently caused by food allergy proteins, which trigger a type-I hypersensitivity reaction in the immune system of atopic individuals. The food allergens in our daily lives are mainly from crops including rice, wheat, soybean and maize. However, allergens in these main crops are far from fully uncovered. Although some bioinformatics tools or methods predicting the potential allergenicity of proteins have been proposed, each method has their limitation. In this paper, we built a novel algorithm PREAL W , which integrated PREAL, FAO/WHO criteria and motif-based method by a weighted average score, to benefit the advantages of different methods. Our results illustrated PREAL W has better performance significantly in the crops' allergen prediction. This integrative allergen prediction algorithm could be useful for critical food safety matters. The PREAL W could be accessed at http://lilab.life.sjtu.edu.cn:8080/prealw .

  11. [A comparative immunochemical analysis of allergoids and allergens].

    Science.gov (United States)

    Fradkin, V A; Tsvetkov, N V; Diakiv, V V; Lavrenchik, E I

    1992-01-01

    In comparison with allergens having protein fragments with a molecular weight not exceeding 110 kD, allergoids have been found to consist of larger fragments with a molecular weight of 10-150 kD. Allergoids have less charged components than initial allergens and less antigenic components. Allergoids retain their capacity for stimulating the production of antibodies, specific to all antigenic components.

  12. The effects of gastric digestion on codfish allergenicity

    DEFF Research Database (Denmark)

    Untersmayr, Eva; Poulsen, Lars K.; Platzer, Michael H

    2005-01-01

    In a recent murine study, we showed that impaired gastric digestion supports the induction of fish allergy by protecting the digestion-sensitive major allergen parvalbumin and thus enhancing its sensitizing properties.......In a recent murine study, we showed that impaired gastric digestion supports the induction of fish allergy by protecting the digestion-sensitive major allergen parvalbumin and thus enhancing its sensitizing properties....

  13. A survey of food allergen control practices in the U.S. food industry.

    Science.gov (United States)

    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.

  14. Reducing dust and allergen exposure in bakeries

    Directory of Open Access Journals (Sweden)

    Howard J Mason

    2017-12-01

    Full Text Available Bakers have a continuing high incidence of occupational allergic asthma. In factory bakeries they are exposed not only to flour dust containing allergens, but also improvers whose ingredients enhance the strength and workability of the dough and its speed of rising. Improvers are flour-based but can contain added soya, fungal or bacterial enzymes that are also allergenic, as well as vegetable oil, calcium sulphate/silicate and organic esters. This study investigated the dustiness of the components used in factory bakeries and whether altering improver ingredients could reduce dust and allergen exposure. A standardised rotating drum test was employed on the individual components, as well as a representative improver and three practicable improver modifications by decreasing calcium sulphate, calcium silicate or increasing oil content. Levels of dust, the allergens wheat flour amylase inhibitor (WAAI and soya trypsin inhibitor (STI were measured in the generated inhalable, thoracic and respirable sized fractions. A “scooping and pouring” workplace simulation was also performed. Initial tests showed that dustiness of several wheat flours was relatively low, and even lower for soya flour, but increased in combination with some other improver components. All three improver modifications generally reduced levels of dust, STI and WAAI, but increasing oil content significantly decreased dust and STI in comparison to the standard improver and those improvers with reduced calcium silicate or sulphate. The simulation demonstrated that increased oil content reduced inhalable levels of gravimetric dust, STI and WAAI. Changing improver formulation, such as increasing oil content of flour by a small amount, may represent a simple, practical method of reducing bakery workers’ exposure to dust and allergens where improvers are used. It may be a useful adjunct to engineering control, changes to work practices and appropriate training in reducing the risk to

  15. Histamine and tryptase in nasal lavage fluid after allergen challenge

    DEFF Research Database (Denmark)

    Jacobi, H H; Skov, P S; Poulsen, L K

    1999-01-01

    BACKGROUND: Antihistamines (H1-receptor antagonists) act by competitive antagonism of histamine at H1-receptors. In addition, high concentrations of some antihistamines inhibit allergen-induced histamine release from mast cells in vitro. OBJECTIVE: The purpose of this study was to determine...... the effect of intranasal azelastine or systemic cetirizine (both potent antihistamines) on the allergen-induced release of mast-cell mediators from the human nasal mucosa in vivo. METHODS: Patients allergic to birch pollen (n = 11) and control subjects not allergic to birch pollen (n = 5) were included......, nasal allergen challenges were performed, and the number of sneezes were counted. In addition, nasal lavage fluid was collected, and the levels of mast-cell mediators (histamine and tryptase) were measured. RESULTS: The allergen challenge of patients allergic to pollen produced sneezing...

  16. The prospects for the research on chemical modifiers of cancer treatment

    International Nuclear Information System (INIS)

    Jin Yizun

    2002-01-01

    The current clinical statue of chemical modifiers of cancer treatment is described. It should enable greater enhancement ratios to be attained clinically. To search for less toxic and more potent sensitizers for radiotherapy and chemotherapy will be improved the cancer treatment. Phase I, II and III clinical trials with TPZ, one of the bioreductive drugs, has shown the benefit to patients with cancer

  17. Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils.

    Science.gov (United States)

    Norbäck, Dan; Markowicz, Pawel; Cai, Gui-Hong; Hashim, Zailina; Ali, Faridah; Zheng, Yi-Wu; Lai, Xu-Xin; Spangfort, Michael Dho; Larsson, Lennart; Hashim, Jamal Hisham

    2014-01-01

    There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96%) from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH), muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm). No cat (Fel d1), dog (Can f 1) or horse allergens (Ecu cx) were detected. The levels of Bloomia tropicalis (Blo t), house dust mite allergens (Der p 1, Der f 1, Der m 1) and cockroach allergens (Per a 1 and Bla g 1) were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective) associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS) and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

  18. Endotoxin, ergosterol, fungal DNA and allergens in dust from schools in Johor Bahru, Malaysia- associations with asthma and respiratory infections in pupils.

    Directory of Open Access Journals (Sweden)

    Dan Norbäck

    Full Text Available There are few studies on associations between respiratory health and allergens, fungal and bacterial compounds in schools in tropical countries. The aim was to study associations between respiratory symptoms in pupils and ethnicity, chemical microbial markers, allergens and fungal DNA in settled dust in schools in Malaysia. Totally 462 pupils (96% from 8 randomly selected secondary schools in Johor Bahru, Malaysia, participated. Dust was vacuumed from 32 classrooms and analysed for levels of different types of endotoxin as 3-hydroxy fatty acids (3-OH, muramic acid, ergosterol, allergens and five fungal DNA sequences. Multiple logistic regression was applied. Totally 13.1% pupils reported doctor's diagnosed asthma, 10.3% wheeze and 21.1% pollen or pet allergy. Indian and Chinese children had less atopy and asthma than Malay. Carbon dioxide levels were low (380-690 ppm. No cat (Fel d1, dog (Can f 1 or horse allergens (Ecu cx were detected. The levels of Bloomia tropicalis (Blo t, house dust mite allergens (Der p 1, Der f 1, Der m 1 and cockroach allergens (Per a 1 and Bla g 1 were low. There were positive associations between levels of Aspergillus versicolor DNA and daytime breathlessness, between C14 3-OH and respiratory infections and between ergosterol and doctors diagnosed asthma. There were negative (protective associations between levels of C10 3-OH and wheeze, between C16 3-OH and day time and night time breathlessness, between cockroach allergens and doctors diagnosed asthma. Moreover there were negative associations between amount of fine dust, total endotoxin (LPS and respiratory infections. In conclusion, endotoxin at school seems to be mainly protective for respiratory illness but different types of endotoxin could have different effects. Fungal contamination measured as ergosterol and Aspergillus versicolor DNA can be risk factors for respiratory illness. The ethnical differences for atopy and asthma deserve further attention.

  19. New Cosmetic Contact Allergens

    Directory of Open Access Journals (Sweden)

    An Goossens

    2015-02-01

    Full Text Available Allergic and photo-allergic contact dermatitis, and immunologic contact urticaria are potential immune-mediated adverse effects from cosmetics. Fragrance components and preservatives are certainly the most frequently observed allergens; however, all ingredients must be considered when investigating for contact allergy.

  20. Beneficial Influence of Short-Term Germination on Decreasing Allergenicity of Peanut Proteins.

    Science.gov (United States)

    Li, Yingchao; Sun, Xiulan; Ma, Zhezhe; Cui, Yan; Du, Chao; Xia, Xiuhua; Qian, He

    2016-01-01

    Most allergenic storage proteins in peanuts are degraded during seed germination. By altering this natural physiological process, it might be possible to reduce peanut protein allergenicity. However, little is known about the change in allergenic proteins and their corresponding immunocreactivity, and the effects of major environmental conditions on their allergenicity during germination. In this study, the influence of different germination conditions (temperature and light) on the degradation of Ara h1 and allergenicity changes of peanut seeds was evaluated by ELISA and Western blotting. The results showed that the 40- and 65-kDa proteins in peanut seeds degraded rapidly during the time course, beginning at 60 (at 25 °C) and 108 h (at 20 °C), and the corresponding immunocreactivity of Ara h1 decreased approximately one-third after 5 to 7 d of germination. Compared with the cotyledons, the embryonic axes had a higher proportion of Ara h1, which was then degraded relatively faster during germination, resulting in a significant reduction in its allergenicity. Although a higher temperature improved the seed germination rate, it affected sprout quality (as did light); therefore, 25 °C and dark surroundings were suitable conditions under which peanut sprouts were processed; neither factor significantly affected the allergenicity of Ara h1. These results provided a theoretical basis for studies using biological methods to reduce peanut allergenicity. © 2015 Institute of Food Technologists®

  1. Towards absolute quantification of allergenic proteins in food--lysozyme in wine as a model system for metrologically traceable mass spectrometric methods and certified reference materials.

    Science.gov (United States)

    Cryar, Adam; Pritchard, Caroline; Burkitt, William; Walker, Michael; O'Connor, Gavin; Burns, Duncan Thorburn; Quaglia, Milena

    2013-01-01

    Current routine food allergen quantification methods, which are based on immunochemistry, offer high sensitivity but can suffer from issues of specificity and significant variability of results. MS approaches have been developed, but currently lack metrological traceability. A feasibility study on the application of metrologically traceable MS-based reference procedures was undertaken. A proof of concept involving proteolytic digestion and isotope dilution MS for quantification of protein allergens in a food matrix was undertaken using lysozyme in wine as a model system. A concentration of lysozyme in wine of 0.95 +/- 0.03 microg/g was calculated based on the concentrations of two peptides, confirming that this type of analysis is viable at allergenically meaningful concentrations. The challenges associated with this promising method were explored; these included peptide stability, chemical modification, enzymatic digestion, and sample cleanup. The method is suitable for the production of allergen in food certified reference materials, which together with the achieved understanding of the effects of sample preparation and of the matrix on the final results, will assist in addressing the bias of the techniques routinely used and improve measurement confidence. Confirmation of the feasibility of MS methods for absolute quantification of an allergenic protein in a food matrix with results traceable to the International System of Units is a step towards meaningful comparison of results for allergen proteins among laboratories. This approach will also underpin risk assessment and risk management of allergens in the food industry, and regulatory compliance of the use of thresholds or action levels when adopted.

  2. Sequential allergen desensitization of basophils is non-specific and may involve p38 MAPK.

    Science.gov (United States)

    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 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 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.

  3. Workshop proceedings: challenges and opportunities in evaluating protein allergenicity across biotechnology industries.

    Science.gov (United States)

    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.

  4. Identification of common allergens for united airway disease by skin prick test

    Directory of Open Access Journals (Sweden)

    Vikas Deep Mishra

    2016-01-01

    Full Text Available Objective: Identification of common allergens by skin prick test in patients of united airway disease. Materials and Methods: Skin prick test was performed in 60 patients of United Airway Disease to identify the common allergens. A total of 62 allergens consisting of 36 types of pollen, 5 fungi, 4 insects, 8 type of dusts, 4 dander, 3 fabrics, Dust mite and Parthenium leaves were tested. Result: Most common allergens were Dust mite (60% followed by Parthenium leaves (45%, insects (18.75%, pollen (14.81%, dust allergens (8.51%, fabrics (8.33%, fungi (5.66%, dander (5%. Most common insect allergens were cockroach (female (30%, cockroach (male (23.33%. Common pollens were Ricinus communis (28.33%, Amaranthus spinosus (28.33%, Parthenium hysterophorus (26.66%, Eucalyptus tereticornis (26.66% and Cynodon dactylon (25%. Common dust allergens were house dust (21.66%, paper dust (11.66% and cotton mill dust (10%. Among fabrics kapok cotton (13.33% showed maximum positivity. Among fungi Aspergillus fumigatus (10% followed by A. niger (6.66% were most common. In animal dander group common ones were cat dander followed by dog dander. Conclusion: In conclusion it can be said that the knowledge drawn by above study will help to treat patients by immunotherapy or avoidance strategy.

  5. Identification of putative and potential cross-reactive chickpea (Cicer arietinum) allergens through an in silico approach.

    Science.gov (United States)

    Kulkarni, Anuja; Ananthanarayan, Laxmi; Raman, Karthik

    2013-12-01

    Allergy has become a key cause of morbidity worldwide. Although many legumes (plants in the Fabaceae family) are healthy foods, they may have a number of allergenic proteins. A number of allergens have been identified and characterized in Fabaceae family, such as soybean and peanut, on the basis of biochemical and molecular biological approaches. However, our understanding of the allergens from chickpea (Cicer arietinum L.), belonging to this family, is very limited. In this study, we aimed to identify putative and cross-reactive allergens from Chickpea (C. arietinum) by means of in silico analysis of the chickpea protein sequences and allergens sequences from Fabaceae family. We retrieved known allergen sequences in Fabaceae family from the IUIS Allergen Nomenclature Database. We performed a protein BLAST (BLASTp) on these sequences to retrieve the similar sequences from chickpea. We further analyzed the retrieved chickpea sequences using a combination of in silico tools, to assess them for their allergenicity potential. Following this, we built structure models using FUGUE: Sequence-structure homology; these models generated by the recognition tool were viewed in Swiss-PDB viewer. Through this in silico approach, we identified seven novel putative allergens from chickpea proteome sequences on the basis of similarity of sequence, structure and physicochemical properties with the known reported legume allergens. Four out of seven putative allergens may also show cross reactivity with reported allergens since potential allergens had common sequence and structural features with the reported allergens. The in silico proteomic identification of the allergen proteins in chickpea provides a basis for future research on developing hypoallergenic foods containing chickpea. Such bioinformatics approaches, combined with experimental methodology, will help delineate an efficient and comprehensive approach to assess allergenicity and pave the way for a better understanding of

  6. Occupational exposure to allergens in oxidative hair dyes

    Directory of Open Access Journals (Sweden)

    Polona Zaletel

    2013-05-01

    Full Text Available Oxidative hair dyes are the most important hair dying products. Hairdressers are exposed to the allergens found in oxidative hair dyes during the process of applying dyes to the hair, when cutting freshly dyed hair, or as a consequence of prior contamination of the working environment. pphenylenediamine, toluene-2,5-diamine and its sulphate are the most common ingredients in oxidative hair dyes that cause allergic contact dermatitis in hairdressers. Cross-reactivity of p-phenylenediamine with para-amino benzoic acid, sulphonamides, sulphonylurea, dapsone, azo dyes, benzocaine, procaine, and black henna temporary tattoos is possible. Allergic contact dermatitis is classified as delayed-type hypersensitivity, according to Coombs and Gell. Skin changes typically appear on the hands after previous sensitization to causative allergens. Combined with the patient’s overall medical and work history and clinical picture, epicutaneous testing is the basic diagnostic procedure for confirming the diagnosis and identifying the causative allergens. The simplest and most effective measure for preventing the occurrence of allergic contact dermatitis in hairdressers is prevention. Preventive measures should be applied as early as in the beginning stage of vocational guidance for this profession. It is important to include health education in the process of professional training and to implement general technical safety measures, in order to reduce sensitization to allergens in hairdressing. Here, special emphasis must be given to the correct use of protective gloves. Legislation must limit the concentration of allergenic substances in hair dyes, based on their potential hazards documented by scientific research.

  7. Allergy assessment of foods or ingredients derived from biotechnology, gene-modified organisms, or novel foods

    DEFF Research Database (Denmark)

    Poulsen, Lars K.

    2004-01-01

    E (IgE) cross-reactions to known allergens, digestability studies of the proteins in simulated gastric and/or intestinal fluids, and animal studies. These steps are discussed and five examples of risk evaluation of GMOs or novel foods are presented. These include ice-structuring protein derived from......The introduction of novel proteins into foods carries a risk of eliciting allergic reactions in individuals sensitive to the introduced protein and a risk of sensitizing susceptible individuals. No single predictive test exists to perform a hazard assessment in relation to allergenic properties...... of newly expressed proteins in gene-modified organisms (GMOs). Instead, performance of a weighted risk analysis based on the decision tree approach has been suggested. The individual steps of this analysis comprise sequence homology to known allergens, specific or targeted serum screens for immunoglobulin...

  8. Comparative analysis of allergen genes and pro-inflammatory factors in pollen and fruit of apple varieties.

    Science.gov (United States)

    Paris, Roberta; Pagliarani, Giulia; Savazzini, Federica; Aloisi, Iris; Iorio, Rosa Anna; Tartarini, Stefano; Ricci, Giampaolo; Del Duca, Stefano

    2017-11-01

    Allergy to freshly consumed apple fruits is often associated to pollinosis and manifested as oral allergy syndrome (OAS). The allergenic properties of apple varieties differ greatly, spanning from low allergenic to high allergenic varieties. The knowledge of the genetic determinants for allergenicity has been of great interest in scientific community for several years, but the molecular mechanisms involved are still little understood. Here, factors putatively involved in allergenicity were investigated at biochemical and molecular level in pollen and in fruits of apple varieties differing in their allergenic potential. Among putative sensitizing factors, transglutaminase (TGase) and phospholipase A 2 (PLA 2 ) were considered together with reactive oxygen species (ROS) and known apple allergen genes, with particular attention devoted to the Mal d 1 gene family, the most important one in sensitization. We found that the expression of some allergen genes and the activities of TGase, PLA 2 and ROS producing enzyme are lower in the hypo-allergenic variety 'Durello di Forlì' in comparison with the high-allergenic genotypes 'Gala' and 'Florina'. These results highlight correlations among allergen expressions, enzymatic activities and apple cultivars; these data underline the possibility that some of them could be used in the future as markers for allergenicity. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Adsorption study of copper (II) by chemically modified orange peel

    International Nuclear Information System (INIS)

    Feng Ningchuan; Guo Xueyi; Liang Sha

    2009-01-01

    An adsorbent, the chemically modified orange peel, was prepared from hydrolysis of the grafted copolymer, which was synthesized by interaction of methyl acrylate with cross-linking orange peel. The presence of poly (acrylic acid) on the biomass surface was verified by infrared spectroscopy (IR), scanning electron microscopy (SEM) and thermogravimetry (TG). Total negative charge in the biomass surface and the zeta potentials were determined. The modified biomass was found to present high adsorption capacity and fast adsorption rate for Cu (II). From Langmuir isotherm, the adsorption capacity for Cu (II) was 289.0 mg g -1 , which is about 6.5 times higher than that of the unmodified biomass. The kinetics for Cu (II) adsorption followed the pseudo-second-order kinetics. The adsorbent was used to remove Cu (II) from electroplating wastewater and was suitable for repeated use for more than four cycles.

  10. Household mold and dust allergens: Exposure, sensitization and childhood asthma morbidity

    Energy Technology Data Exchange (ETDEWEB)

    Gent, Janneane F., E-mail: janneane.gent@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Kezik, Julie M., E-mail: julie.colburn@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Hill, Melissa E., E-mail: melissa.hill@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Tsai, Eling, E-mail: tsai.umiami@gmail.com [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Li, De-Wei, E-mail: DeWei.Li@ct.gov [Connecticut Agricultural Experiment Station, Valley Laboratory, 153 Cook Hill Road, Windsor, CT 06095 (United States); Leaderer, Brian P., E-mail: brian.leaderer@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States)

    2012-10-15

    Background: Few studies address concurrent exposures to common household allergens, specific allergen sensitization and childhood asthma morbidity. Objective: To identify levels of allergen exposures that trigger asthma exacerbations in sensitized individuals. Methods: We sampled homes for common indoor allergens (fungi, dust mites (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1) and cockroach (Bla g 1)) for levels associated with respiratory responses among school-aged children with asthma (N=1233) in a month-long study. Blood samples for allergy testing and samples of airborne fungi and settled dust were collected at enrollment. Symptoms and medication use were recorded on calendars. Combined effects of specific allergen sensitization and level of exposure on wheeze, persistent cough, rescue medication use and a 5-level asthma severity score were examined using ordered logistic regression. Results: Children sensitized and exposed to any Penicillium experienced increased risk of wheeze (odds ratio [OR] 2.12 95% confidence interval [CI] 1.12, 4.04), persistent cough (OR 2.01 95% CI 1.05, 3.85) and higher asthma severity score (OR 1.99 95% CI 1.06, 3.72) compared to those not sensitized or sensitized but unexposed. Children sensitized and exposed to pet allergen were at significantly increased risk of wheeze (by 39% and 53% for Fel d 1>0.12 {mu}g/g and Can f 1>1.2 {mu}g/g, respectively). Increased rescue medication use was significantly associated with sensitization and exposure to Der p 1>0.10 {mu}g/g (by 47%) and Fel d 1>0.12 {mu}g/g (by 32%). Conclusion: Asthmatic children sensitized and exposed to low levels of common household allergens Penicillium, Der p 1, Fel d 1 and Can f 1 are at significant risk for increased morbidity. - Highlights: Black-Right-Pointing-Pointer Few studies address concurrent allergen exposures, sensitization and asthma morbidity. Black-Right-Pointing-Pointer Children with asthma were tested for sensitivity to common indoor allergens

  11. AllerHunter: a SVM-pairwise system for assessment of allergenicity and allergic cross-reactivity in proteins.

    Directory of Open Access Journals (Sweden)

    Hon Cheng Muh

    Full Text Available Allergy is a major health problem in industrialized countries. The number of transgenic food crops is growing rapidly creating the need for allergenicity assessment before they are introduced into human food chain. While existing bioinformatic methods have achieved good accuracies for highly conserved sequences, the discrimination of allergens and non-allergens from allergen-like non-allergen sequences remains difficult. We describe AllerHunter, a web-based computational system for the assessment of potential allergenicity and allergic cross-reactivity in proteins. It combines an iterative pairwise sequence similarity encoding scheme with SVM as the discriminating engine. The pairwise vectorization framework allows the system to model essential features in allergens that are involved in cross-reactivity, but not limited to distinct sets of physicochemical properties. The system was rigorously trained and tested using 1,356 known allergen and 13,449 putative non-allergen sequences. Extensive testing was performed for validation of the prediction models. The system is effective for distinguishing allergens and non-allergens from allergen-like non-allergen sequences. Testing results showed that AllerHunter, with a sensitivity of 83.4% and specificity of 96.4% (accuracy = 95.3%, area under the receiver operating characteristic curve AROC = 0.928+/-0.004 and Matthew's correlation coefficient MCC = 0.738, performs significantly better than a number of existing methods using an independent dataset of 1443 protein sequences. AllerHunter is available at (http://tiger.dbs.nus.edu.sg/AllerHunter.

  12. Adhesive and morphological characteristics of surface chemically modified polytetrafluoroethylene films

    International Nuclear Information System (INIS)

    Hopp, B.; Kresz, N.; Kokavecz, J.; Smausz, T.; Schieferdecker, H.; Doering, A.; Marti, O.; Bor, Z.

    2004-01-01

    In the present paper, we report an experimental determination of adhesive and topographic characteristics of chemically modified surface of polytetrafluoroethylene (PTFE) films. The surface chemistry was modified by ArF excimer laser irradiation in presence of triethylene-tetramine photoreagent. The applied laser fluence was varied in the range of 0.4-9 mJ/cm 2 , and the number of laser pulses incident on the same area was 1500. To detect the changes in the adhesive features of the treated Teflon samples, we measured receding contact angle for distilled water and adhesion strength, respectively. It was found that the receding contact angle decreased from 96 deg. to 30-37 deg. and the adhesion strength of two-component epoxy glue to the treated sample surface increased from 0.03 to 9 MPa in the applied laser fluence range. Additionally, it was demonstrated that the adhesion of human cells to the modified Teflon samples is far better than to the untreated ones. The contact mode and pulsed force mode atomic force microscopic investigations of the treated samples demonstrated that the measured effective contact area of the irradiated films does not differ significantly from that of the original films, but the derived adhesion force is stronger on the modified samples than on the untreated ones. Hence, the increased adhesion of the treated Teflon films is caused by the higher surface energy

  13. Rational design of hypoallergens applied to the major cat allergen Fel d 1.

    Science.gov (United States)

    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.

  14. Evaluation of allergenicity of constituents of myoga using the murine local lymph node assay.

    Science.gov (United States)

    Wei, Q J; Wei, C N; Harada, K; Minamoto, K; Okamoto, Y; Otsuka, M; Ueda, A

    2010-01-01

    Myoga (Zingiber Myoga Roscoe) is a perennial plant with a pungent smell from its flower buds. It is native to East Asia and has been reported to cause allergic contact dermatitis. The purpose of this study is to assess the allergenicity of myoga related to its major chemical components, alpha-pinene, beta-pinene, limonene, limonene oxide and beta-phellandrene, which are supposed to be the causative agents of contact dermatitis among myoga cultivators. We performed a toxicity study of the volatile constituents of myoga using the local lymph node assay (LLNA), in which limonene, limonene oxide and beta-phellandrene had positive responses and the EC3 was 35.8%, 8.22%, and 0.54%, respectively. EC3 for both alpha-pinene and beta-pinene was over 100%. Both chemicals failed to induce positive responses in the LLNA. While the maximization rating of limonene, limonene oxide and phellandrene were evaluated as moderate, extreme, and extreme respectively, alpha-pinene and beta-pinene were evaluated as weak in the previously reported GPMT. The usage of LLNA was also confirmed by comparing with previously reported GPMT results to detect the allergenicity of myoga constituents. The actual risk of humans developing an allergy to myoga constituents depends on many factors. The concentration of the compounds, the frequency and duration of exposure and the condition of the skin are supposed to be important factors.

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

    NARCIS (Netherlands)

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

    2015-01-01

    Background 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

  16. Identification of snake venom allergens by two-dimensional electrophoresis followed by immunoblotting.

    Science.gov (United States)

    Hu, Yujing; Yang, Liming; Yang, Haiwei; He, Shaoheng; Wei, Ji-Fu

    2017-01-01

    This allergic reaction to snake venom was described to occur in patients after recurrent exposure through bites in amateur and professional snake handlers, which might be underestimated and contribute to fatal snakebites in victim, independently from the toxicity of the venom itself. Few allergens were identified from snake venoms by normal SDS-PAGE, which cannot separate the snake venom completely. In the present study, we identified nine potential allergens by two-dimensional (2D) electrophoresis followed by immunoblotting (named as allergenomics) in Protobothrops mucrosquamatus venom. By multidimensional liquid chromatography-ion trap mass spectrometry (MDLC-ESI-LTQ-MS/MS) analysis, six allergens showed sequence similarity to snake venom serine proteinases. Other allergens showed sequence similarity to snake venom metalloproteinase. These allergic reactions to snake venom allergens might contribute to fatal snakebites in victim, independently. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Sensitivity to the Main Allergens in Children with Allergic Diseases

    Directory of Open Access Journals (Sweden)

    O.D. Kuznietsova

    2015-11-01

    Objective of the research — to study hypersensitivity to the main allergens in children with allergic diseases based on the results of skin allergy testing, as well as to analyze the structure of diseases. Materials and methods. We have examined 228 children using skin prick testing, the estimation of results was conducted 25–40 minutes after performing the test. Associations between the results of skin prick test with various allergens were studied using cross-correlation analysis in the package of applied statistics Statistics 6.0. Results. 85.5 % of children were sensitized to the pollen allergens, domestic — 54 %, food — 21 %, fungal allergens — 35 %. Among pollen plants, there prevails sensitization to ambrosia — 47.8 %, sunflower — 49.5 %, cyclachaena — 38.5 %; among domestic allergens — to the tick species D.рteronyssinus and D.farinae — 24 %, cat hair — 19.7 %, among fungal — to Alternaria (23 %. Most often hyperergic reaction (papule diameter ≥ 8 mm was observed to cyclachaena (44 %, sunflower (46 %, ambrosia (50 %, cat hair (42 %, D.farinae (39 %. We have established significant (р < 0.05 correlations of mainly middle strength between positive prick-tests in pairs: ambrosia — cyclachaena (r = +0.43, ambrosia — sunflower (r = +0.43, acarus D.рteronyssinus — D.farinae (r = +0.66, mixture «birch, alder, oak, hazel» — ryegrass (r = +0.53, beef meat — egg yolk (r = +0.42, pork meat — chicken meat (r = +0.35, milk (r = +0.36, wool of sheep — pork (r = +0.36. Conclusion. Predominance of sensitization to pollen allergens represents the epidemiological situation in the South region of Ukraine. The presence of correlations between the different types of allergens indicates the cross reactions between them. In case of multiple positive results of skin allergen tests, the study using molecular allergy diagnostic method is recommended to establish genuine or cross allergy.

  18. Progress in the study of reducing food allergenicity by irradiation

    International Nuclear Information System (INIS)

    Gu Kefei; Gao Meixu; Li Chunhong; Pan Jiarong

    2006-01-01

    Food allergy becomes an important factor in food safety areas. As one of the methods to cure allergy, reducing food allergenicity by irradiation becomes a hot topic. This article reviewed the present situation and the mechanism of reducing food allergenicity by irradiation. (authors)

  19. Contents of fragrance allergens in children's cosmetics and cosmetic-toys

    DEFF Research Database (Denmark)

    Rastogi, Suresh Chandra; Johansen, J D; Menné, T

    1999-01-01

    were analysed by gas chromatography - mass spectrometry. Target substances were the fragrance allergens from the fragrance mix and 14 other fragrance substances, most of which have been described as contact allergens. The fragrance mix ingredients were either not present in children's shampoos...

  20. Challenges in the implementation of EAACI guidelines on allergen immunotherapy

    DEFF Research Database (Denmark)

    Bonertz, A; Roberts, G C; Hoefnagel, M

    2018-01-01

    Regulatory approaches for allergen immunotherapy (AIT) products and the availability of high-quality AIT products are inherently linked to each other. While allergen products are available in many countries across the globe, their regulation is very heterogeneous. First, we describe the regulator...

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

    Science.gov (United States)

    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.

  2. Databases and Associated Bioinformatic Tools in Studies of Food Allergens, Epitopes and Haptens – a Review

    Directory of Open Access Journals (Sweden)

    Bucholska Justyna

    2018-06-01

    Full Text Available Allergies and/or food intolerances are a growing problem of the modern world. Diffi culties associated with the correct diagnosis of food allergies result in the need to classify the factors causing allergies and allergens themselves. Therefore, internet databases and other bioinformatic tools play a special role in deepening knowledge of biologically-important compounds. Internet repositories, as a source of information on different chemical compounds, including those related to allergy and intolerance, are increasingly being used by scientists. Bioinformatic methods play a signifi cant role in biological and medical sciences, and their importance in food science is increasing. This study aimed at presenting selected databases and tools of bioinformatic analysis useful in research on food allergies, allergens (11 databases, epitopes (7 databases, and haptens (2 databases. It also presents examples of the application of computer methods in studies related to allergies.

  3. Association of pediatric asthma severity with exposure to common household dust allergens

    International Nuclear Information System (INIS)

    Gent, Janneane F.; Belanger, Kathleen; Triche, Elizabeth W.; Bracken, Michael B.; Beckett, William S.; Leaderer, Brian P.

    2009-01-01

    Background: Reducing exposure to household dust inhalant allergens has been proposed as one strategy to reduce asthma. Objective: To examine the dose-response relationships and health impact of five common household dust allergens on disease severity, quantified using both symptom frequency and medication use, in atopic and non-atopic asthmatic children. Methods: Asthmatic children (N=300) aged 4-12 years were followed for 1 year. Household dust samples from two indoor locations were analyzed for allergens including dust mite (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1), cockroach (Bla g 1). Daily symptoms and medication use were collected in monthly telephone interviews. Annual disease severity was examined in models including allergens, specific IgE sensitivity and adjusted for age, gender, atopy, ethnicity, and mother's education. Results: Der p 1 house dust mite allergen concentration of 2.0 μg/g or more from the main room and the child's bed was related to increased asthma severity independent of allergic status (respectively, OR 2.93, 95% CI 1.37, 6.30 for 2.0-10.0 μg/g and OR 2.55 95% CI 1.13, 5.73 for ≥10.0 μg/g). Higher pet allergen levels were associated with greater asthma severity, but only for those sensitized (cat OR 2.41 95% CI 1.19, 4.89; dog OR 2.06 95% CI 1.01, 4.22). Conclusion: Higher levels of Der p 1 and pet allergens were associated with asthma severity, but Der p 1 remained an independent risk factor after accounting for pet allergens and regardless of Der p 1 specific IgE status.

  4. Association of pediatric asthma severity with exposure to common household dust allergens

    Energy Technology Data Exchange (ETDEWEB)

    Gent, Janneane F., E-mail: janneane.gent@yale.edu [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Belanger, Kathleen [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Triche, Elizabeth W. [Brown University, Department of Community Health/Epidemiology, Providence, RI (United States); Bracken, Michael B. [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States); Beckett, William S. [Mount Auburn Hospital, Department of Internal Medicine, Cambridge, MA (United States); Leaderer, Brian P. [Yale Center for Perinatal, Pediatric and Environmental Epidemiology, Department of Epidemiology and Public Health, Yale University School of Medicine, One Church Street, 6th Floor, New Haven, CT 06510 (United States)

    2009-08-15

    Background: Reducing exposure to household dust inhalant allergens has been proposed as one strategy to reduce asthma. Objective: To examine the dose-response relationships and health impact of five common household dust allergens on disease severity, quantified using both symptom frequency and medication use, in atopic and non-atopic asthmatic children. Methods: Asthmatic children (N=300) aged 4-12 years were followed for 1 year. Household dust samples from two indoor locations were analyzed for allergens including dust mite (Der p 1, Der f 1), cat (Fel d 1), dog (Can f 1), cockroach (Bla g 1). Daily symptoms and medication use were collected in monthly telephone interviews. Annual disease severity was examined in models including allergens, specific IgE sensitivity and adjusted for age, gender, atopy, ethnicity, and mother's education. Results: Der p 1 house dust mite allergen concentration of 2.0 {mu}g/g or more from the main room and the child's bed was related to increased asthma severity independent of allergic status (respectively, OR 2.93, 95% CI 1.37, 6.30 for 2.0-10.0 {mu}g/g and OR 2.55 95% CI 1.13, 5.73 for {>=}10.0 {mu}g/g). Higher pet allergen levels were associated with greater asthma severity, but only for those sensitized (cat OR 2.41 95% CI 1.19, 4.89; dog OR 2.06 95% CI 1.01, 4.22). Conclusion: Higher levels of Der p 1 and pet allergens were associated with asthma severity, but Der p 1 remained an independent risk factor after accounting for pet allergens and regardless of Der p 1 specific IgE status.

  5. Proteomics analysis of dendritic cell activation by contact allergens reveals possible biomarkers regulated by Nrf2

    Energy Technology Data Exchange (ETDEWEB)

    Mussotter, Franz, E-mail: franz.mussotter@bfr.bund.de [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany); Tomm, Janina Melanie [Helmholtz Centre for Environmental Research (UFZ), Department of Molecular Systems Biology, Leipzig (Germany); El Ali, Zeina; Pallardy, Marc; Kerdine-Römer, Saadia [INSERM UMR 996, Univ Paris-Sud, Université Paris-Saclay, Chátenay-Malabry (France); Götz, Mario [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany); Bergen, Martin von [Helmholtz Centre for Environmental Research (UFZ), Department of Molecular Systems Biology, Leipzig (Germany); University of Leipzig, Institute of Biochemistry, Leipzig (Germany); Aalborg University, Department of Chemistry and Bioscience, Aalborg (Denmark); Haase, Andrea; Luch, Andreas [German Federal Institute for Risk Assessment (BfR), Department of Chemical and Product Safety, Berlin (Germany)

    2016-12-15

    Allergic contact dermatitis is a widespread disease with high clinical relevance affecting approximately 20% of the general population. Typically, contact allergens are low molecular weight electrophilic compounds which can activate the Keap1/Nrf2 pathway. We performed a proteomics study to reveal possible biomarkers for dendritic cell (DC) activation by contact allergens and to further elucidate the role of Keap1/Nrf2 signaling in this process. We used bone marrow derived dendritic cells (BMDCs) of wild-type (nrf2{sup +/+}) and Nrf2 knockout (nrf2{sup −/−}) mice and studied their response against the model contact sensitizers 2,4-dinitrochlorobenzene (DNCB), cinnamaldehyde (CA) and nickel(II) sulfate by 2-dimensional polyacrylamide gel electrophoresis (2D-PAGE) in combination with electrospray ionization tandem mass spectrometry (ESI-MS/MS). Sodium dodecyl sulfate (SDS, 100 μM) served as irritant control. While treatment with nickel(II) sulfate and SDS had only little effects, CA and DNCB led to significant changes in protein expression. We found 18 and 30 protein spots up-regulated in wild-type cells treated with 50 and 100 μM CA, respectively. For 5 and 10 μM DNCB, 32 and 37 spots were up-regulated, respectively. Almost all of these proteins were not differentially expressed in nrf2{sup −/−} BMDCs, indicating an Nrf2-dependent regulation. Among them proteins were detected which are involved in oxidative stress and heat shock responses, as well as in signal transduction or basic cellular pathways. The applied approach allowed us to differentiate between Nrf2-dependent and Nrf2-independent cellular biomarkers differentially regulated upon allergen-induced DC activation. The data presented might contribute to the further development of suitable in vitro testing methods for chemical-mediated sensitization. - Highlights: • Contact allergens induce proteins involved in DC maturation Nrf2-dependently. • Induction of these proteins points to a functional

  6. Food allergens of plant origin - their molecular and evolutionary relationships

    DEFF Research Database (Denmark)

    Mills, E. N. C.; Madsen, Charlotte Bernhard; Shewry, P. R.

    2003-01-01

    Along with other forms of allergic disease, food allergies appear to be on the increase, with childhood allergies to foods such as peanuts being of particular concern. Around 7-10 foods are responsible for the majority of allergies, including several of plant origin, notably peanut. Allergies...... are usually triggered by the protein components in a food, which are also known as allergens. However, not all the proteins in an allergenic food like peanut are allergens. Why should this be? This question has been addressed by an EU-funded inter-disciplinary network of clinicians, food chemists and plant...

  7. Fast vertical growth of ZnO nanorods using a modified chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Tae-hyun [Department of Nano Systems Engineering, Center for Nano Manufacturing, Inje University, Obang-dong, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Ryu, Hyukhyun, E-mail: hhryu@inje.ac.kr [Department of Nano Systems Engineering, Center for Nano Manufacturing, Inje University, Obang-dong, Gimhae, Gyeongnam 621-749 (Korea, Republic of); Lee, Won-Jae [Department of Materials and Components Engineering, Dong-Eui University, 995 Eomgwangno, Busanjin-gu, Busan 614-714 (Korea, Republic of)

    2014-06-01

    Highlights: • We grew vertical ZnO nanorods by a modified CBD process with a fast growth rate. • We studied the effects of the CBD process by varying growth temperature, time, and concentration. • The ZnO nanorods grown by the modified CBD showed good morphological and structural properties. - Abstract: In this study, we grew vertical ZnO nanorods on seeded Si (1 0 0) substrates using a modified chemical bath deposition (CBD). We investigated the effects of the growth temperature, growth time and concentration on the morphological and structural properties of the ZnO nanorods using field emission gun scanning electron microscopy (FEG-SEM) and X-ray diffraction. This modified CBD method shows improved results over conventional CBD. ZnO nanorods with good structural XRD properties were grown with a very fast growth rate in a wide range of growth conditions and did not require post-growth annealing.

  8. Expression of Colocasia esculenta tuber agglutinin in Indian mustard provides resistance against Lipaphis erysimi and the expressed protein is non-allergenic.

    Science.gov (United States)

    Das, Ayan; Ghosh, Prithwi; Das, Sampa

    2018-06-01

    Transgenic Brassica juncea plants expressing Colocasia esculenta tuber agglutinin (CEA) shows the non-allergenic nature of the expressed protein leading to enhanced mortality and reduced fecundity of mustard aphid-Lipaphis erysimi. Lipaphis erysimi (common name: mustard aphid) is the most devastating sucking insect pest of Indian mustard (Brassica juncea L.). Colocasia esculenta tuber agglutinin (CEA), a GNA (Galanthus nivalis agglutinin)-related lectin has previously been reported by the present group to be effective against a wide array of hemipteran insects in artificial diet-based bioassays. In the present study, efficacy of CEA in controlling L. erysimi has been established through the development of transgenic B. juncea expressing this novel lectin. Southern hybridization of the transgenic plants confirmed stable integration of cea gene. Expression of CEA in T 0 , T 1 and T 2 transgenic plants was confirmed through western blot analysis. Level of expression of CEA in the T 2 transgenic B. juncea ranged from 0.2 to 0.47% of the total soluble protein. In the in planta insect bioassays, the CEA expressing B. juncea lines exhibited enhanced insect mortality of 70-81.67%, whereas fecundity of L. erysimi was reduced by 49.35-62.11% compared to the control plants. Biosafety assessment of the transgenic B. juncea protein containing CEA was carried out by weight of evidence approach following the recommendations by FAO/WHO (Evaluation of the allergenicity of genetically modified foods: report of a joint FAO/WHO expert consultation, 22-25 Jan, Rome, http://www.fao.org/docrep/007/y0820e/y0820e00.HTM , 2001), Codex (Codex principles and guidelines on foods derived from biotechnology, Food and Agriculture Organization of the United Nations, Rome; Codex, Codex principles and guidelines on foods derived from biotechnology, Food and Agriculture Organization of the United Nations, Rome, 2003) and ICMR (Indian Council of Medical Research, guidelines for safety assessment of

  9. A review of clinical efficacy, safety, new developments and adherence to allergen-specific immunotherapy in patients with allergic rhinitis caused by allergy to ragweed pollen (Ambrosia artemisiifolia

    Directory of Open Access Journals (Sweden)

    Turkalj M

    2017-02-01

    Full Text Available Mirjana Turkalj,1,2 Ivana Banic,1 Srdjan Ante Anzic1 1Children’s Hospital Srebrnjak, Zagreb, 2Faculty of Medicine, JJ Strossmayer University of Osijek, Osijek, Croatia Abstract: Allergic rhinitis is a common health problem in both children and adults. The number of patients allergic to ragweed (Ambrosia artemisiifolia is on the rise throughout Europe, having a significant negative impact on the patients’ and their family’s quality of life. Allergen-specific immunotherapy (AIT has disease-modifying effects and can induce immune tolerance to allergens. Both subcutaneous immunotherapy and sublingual immunotherapy with ragweed extracts/preparations have clear positive clinical efficacy, especially over pharmacological treatment, even years after the treatment has ended. AIT also has very good safety profiles with extremely rare side effects, and the extracts/preparations used in AIT are commonly well tolerated by patients. However, patient adherence to treatment with AIT seems to be quite low, mostly due to the fact that treatment with AIT is relatively time-demanding and, moreover, due to patients not receiving adequate information and education about the treatment before it starts. AIT is undergoing innovations and improvements in clinical efficacy, safety and patient adherence, especially with new approaches using new adjuvants, recombinant or modified allergens, synthetic peptides, novel routes of administration (epidermal or intralymphatic, and new protocols, which might make AIT more acceptable for a wider range of patients and novel indications. Patient education and support (eg, recall systems is one of the most important goals for AIT in the future, to further enhance treatment success. Keywords: allergic rhinitis, allergy, ragweed, allergen-specific immunotherapy, Ambrosia artemisiifolia

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

    Science.gov (United States)

    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.

  11. [Genetically modified food--great unknown].

    Science.gov (United States)

    Cichosz, G; Wiackowski, S K

    2012-08-01

    Genetically modified food (GMF) creates evident threat to consumers' health. In spite of assurances of biotechnologists, DNA of transgenic plants is instable, so, synthesis of foreign, allergenic proteins is possible. Due to high trypsin inhibitor content the GMF is digested much more slowly what, alike Bt toxin presence, increases probability of alimentary canal diseases. Next threats are bound to the presence of fitoestrogens and residues of Roundup pesticide, that can diminish reproductiveness; and even lead to cancerogenic transformation through disturbance of human hormonal metabolism. In spite of food producers and distributors assurances that food made of GMF raw materials is marked, de facto consumers have no choice. Moreover, along the food law products containing less than 0.9% of GMF protein are not included into genetically modified food.

  12. Allergen immunotherapy induces a suppressive memory response mediated by IL-10 in a mouse asthma model

    NARCIS (Netherlands)

    Vissers, Joost L. M.; van Esch, Betty C. A. M.; Hofman, Gerard A.; Kapsenberg, Martien L.; Weller, Frank R.; van Oosterhout, Antoon J. M.

    2004-01-01

    Background: Human studies have demonstrated that allergen immunotherapy induces memory suppressive responses and IL-10 production by allergen-specific T cells. Previously, we established a mouse model in which allergen immunotherapy was effective in the suppression of allergen-induced asthma

  13. A competitive solid-phase radioimmunoassay for quantitation of the major allergen of Parietaria pollen

    International Nuclear Information System (INIS)

    Corbi, A.L.; Ayuso, R.; Lombardero, M.; Duffort, O.; Carreira, J.

    1985-01-01

    A competitive solid-phase radioimmunoassay has been developed for quantitation of the major allergen of Parietaria judaica pollen. The assay is based on: (1) the ability of AC/1.1 monoclonal antibody to bind specifically to the P. judaica major allergen, and (2) the ability of crude pollen extracts or purified allergen to inhibit the binding of 125 I-labelled allergen to solid-phase-bound AC/1.1 monoclonal antibody. The assay is sensitive enough to detect as little as 10 ng of allergen. A good correlation is found when the results obtained are compared with those produced by RAST inhibition (r = 0.95; P < 0.001). Thus, this method can also be used for the estimation of the allergenic activity of P. judaica pollen extracts. The assay is easily completed in 2 h, allowing simultaneous analysis of a number of extracts. (Auth.)

  14. Pollen-Associated Microbiome Correlates with Pollution Parameters and the Allergenicity of Pollen.

    Directory of Open Access Journals (Sweden)

    Andrea Obersteiner

    Full Text Available Pollen allergies have been rapidly increasing over the last decades. Many allergenic proteins and non-allergenic adjuvant compounds of pollen are involved in the plant defense against environmental or microbial stress. The first aim of this study was to analyze and compare the colonizing microbes on allergenic pollen. The second aim was to investigate detectable correlations between pollen microbiota and parameters of air pollution or pollen allergenicity. To reach these aims, bacterial and fungal DNA was isolated from pollen samples of timothy grass (Phleum pratense, n = 20 and birch trees (Betula pendula, n = 55. With this isolated DNA, a terminal restriction fragment length polymorphism analysis was performed. One result was that the microbial diversity on birch tree and timothy grass pollen samples (Shannon/Simpson diversity indices was partly significantly correlated to allergenicity parameters (Bet v 1/Phl p 5, pollen-associated lipid mediators. Furthermore, the microbial diversity on birch pollen samples was correlated to on-site air pollution (nitrogen dioxide (NO2, ammonia (NH3, and ozone (O3. What is more, a significant negative correlation was observed between the microbial diversity on birch pollen and the measured NO2 concentrations on the corresponding trees. Our results showed that the microbial composition of pollen was correlated to environmental exposure parameters alongside with a differential expression of allergen and pollen-associated lipid mediators. This might translate into altered allergenicity of pollen due to environmental and microbial stress.

  15. Chemical switches and logic gates based on surface modified semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Konrad, Szacilowski; Wojciech, Macyk [Jagiellonian Univ., Dept. of Chemistry, Krakow (Poland)

    2006-02-15

    Photoelectrochemical properties of multicomponent photo-electrodes based on titanium dioxide and cadmium sulfide powders modified with hexacyanoferrate complexes have been examined. Photocurrent responses were recorded as functions of applied potential and photon energy. Surprisingly, the photocurrent can be switched between positive and negative values as a result of potential or photon energy changes. This new effect called Photo Electrochemical Photocurrent Switching (PEPS) opens a possibility of new chemical switches and logic gates construction. Boolean logic analysis and a tentative mechanism of the device are discussed. (authors)

  16. Allergen manufacturing and quality aspects for allergen immunotherapy in Europe and the United States

    DEFF Research Database (Denmark)

    Bonertz, A; Roberts, G; Slater, J E

    2018-01-01

    Adequate quality is essential for any medicinal product to be eligible for marketing. Quality includes verification of the identity, content and purity of a medicinal product in combination with a specified production process and its control. Allergen products derived from natural sources require...

  17. Biochemical and immunological characterization of recombinant allergen Lol p 1.

    Science.gov (United States)

    Tamborini, E; Faccini, S; Lidholm, J; Svensson, M; Brandazza, A; Longhi, R; Groenlund, H; Sidoli, A; Arosio, P

    1997-11-01

    Pollen from perennial rye grass (Lolium perenne), a major cause of type-I allergy worldwide, contains a complex mixture of allergenic proteins among which Lol p 1 is one of the most important. We describe the expression, purification and characterization of a recombinant Lol p 1 overproduced in Escherichia coli. The recombinant allergen, expressed in high yields and purified in milligram amounts, bound to specific IgE antibodies from human sera, induced histamine release from sensitized human basophils, and elicited rabbit antisera that recognize specifically recombinant Lol p 1 and natural Lol p 1 of pollen extract. Recombinant Lol p 1 was used to develop ImmunoCAP assays for analysis of 150 sera that were Radioallergosorbent test positive to L. perenne pollen. In 130 of them (87%) the assay detected a significant level of IgE antibodies to Lol p 1, reaching on average 37% of the level obtained with a test for IgE to the whole grass pollen extract. To map epitopes on Lol p 1, we produced three deletion mutants [des-(116-240)-Lol p 1, des-(1-88)-Lol p 1 and des-(133-189)-Lol p 1], which were efficiently expressed in bacteria. These all showed a strong reactivity with the specific rabbit IgG antibodies, but lacked most or all the allergenic properties of recombinant Lol p 1. A study of the antigenic structure of Lol p 1 was performed using the three deletion mutants and a set of 17-18-residue overlapping synthetic peptides covering the whole allergen sequence. The results indicate that human IgE and rabbit IgG antibodies bind to distinct regions of Lol p 1, and that at least some important IgE epitopes are mainly conformational. The findings suggest that recombinant allergens constitute useful reagents for further development of serological diagnosis of allergy, and that it should be possible to produce immunogenic fragments of allergenic proteins without allergenic properties.

  18. Genetically modified soybeans and food allergies.

    Science.gov (United States)

    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.

  19. Allergenic pollen pollinosis in Madrid.

    Science.gov (United States)

    Subiza, J; Jerez, M; Jiménez, J A; Narganes, M J; Cabrera, M; Varela, S; Subiza, E

    1995-07-01

    A 15-year pollen count was performed in the atmosphere of Madrid, Spain, to determine the months in which the highest concentrations of allergenic pollens occur. Pollen counts were done with a Burkard spore trap (Burkard Manufacturing, Rickmansworth, Herst., U.K.). The results were subsequently compared with results of skin tests in patients with pollinosis born and living in and around Madrid. The highest airborne presence (percent of total yearly pollen counts, mean of counts from 1979 to 1993) was for Quercus spp. (17%); followed by Platanus spp. (15%), Poaceae (15%), Cupressaceae (11%), Olea spp. (9%), Pinus spp. (7%), Populus spp. (4%), and Plantago spp. (4%). The most predominant pollens from January to April are tree pollens (Cupressaceae, Alnus, Fraxinus, Ulmus, Populus, Platanus, and Morus), although these are also abudant in May and June (Quercus, Olea, and Pinus spp.). The grass pollination period shows a double curve: the first peak occurs from February to April (8% of yearly grasses), and the second peak occurs from May to July (90% of yearly grasses). Among allergenically significant weeds, the most notable is Plantago; in contrast, Rumex, Urticaceae, Cheno-Amaranthaceae, and Artemisia spp. have very low concentrations (arizonica (20%). The population of Madrid is exposed to high concentrations of allergenic pollen from February to July, although the most intense period is from May to June. Grass pollens are the most important cause of pollinosis in this area.

  20. Genetically modified foods and allergy.

    Science.gov (United States)

    Lee, T H; Ho, H K; Leung, T F

    2017-06-01

    2015 marked the 25th anniversary of the commercial use and availability of genetically modified crops. The area of planted biotech crops cultivated globally occupies a cumulative two billion hectares, equivalent to twice the land size of China or the United States. Foods derived from genetically modified plants are widely consumed in many countries and genetically modified soybean protein is extensively used in processed foods throughout the industrialised countries. Genetically modified food technology offers a possible solution to meet current and future challenges in food and medicine. Yet there is a strong undercurrent of anxiety that genetically modified foods are unsafe for human consumption, sometimes fuelled by criticisms based on little or no firm evidence. This has resulted in some countries turning away food destined for famine relief because of the perceived health risks of genetically modified foods. The major concerns include their possible allergenicity and toxicity despite the vigorous testing of genetically modified foods prior to marketing approval. It is imperative that scientists engage the public in a constructive evidence-based dialogue to address these concerns. At the same time, improved validated ways to test the safety of new foods should be developed. A post-launch strategy should be established routinely to allay concerns. Mandatory labelling of genetically modified ingredients should be adopted for the sake of transparency. Such ingredient listing and information facilitate tracing and recall if required.

  1. Assessment of immunotoxicity induced by chemicals in human precision-cut lung slices (PCLS).

    Science.gov (United States)

    Lauenstein, L; Switalla, S; Prenzler, F; Seehase, S; Pfennig, O; Förster, C; Fieguth, H; Braun, A; Sewald, K

    2014-06-01

    Occupational asthma can be induced by a number of chemicals at the workplace. Risk assessment of potential sensitizers is mostly performed in animal experiments. With increasing public demand for alternative methods, human precision-cut lung slices (PCLS) have been developed as an ex vivo model. Human PCLS were exposed to increasing concentrations of 20 industrial chemicals including 4 respiratory allergens, 11 contact allergens, and 5 non-sensitizing irritants. Local respiratory irritation was characterized and expressed as 75% (EC25) and 50% (EC50) cell viability with respect to controls. Dose-response curves of all chemicals except for phenol were generated. Local respiratory inflammation was quantified by measuring the production of cytokines and chemokines. TNF-α and IL-1α were increased significantly in human PCLS after exposure to the respiratory sensitizers trimellitic anhydride (TMA) and ammonium hexachloroplatinate (HClPt) at subtoxic concentrations, while contact sensitizers and non-sensitizing irritants failed to induce the release of these cytokines to the same extent. Interestingly, significant increases in T(H)1/T(H)2 cytokines could be detected only after exposure to HClPt at a subtoxic concentration. In conclusion, allergen-induced cytokines were observed but not considered as biomarkers for the differentiation between respiratory and contact sensitizers. Our preliminary results show an ex vivo model which might be used for prediction of chemical-induced toxicity, but is due to its complex three-dimensional structure not applicable for a simple screening of functional and behavior changes of certain cell populations such as dendritic cells and T-cells in response to allergens. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  2. Encapsulating contact allergens in liposomes, ethosomes, and polycaprolactone may affect their sensitizing properties

    DEFF Research Database (Denmark)

    Madsen, Jakob Torp; Vogel, Stefan; Johansen, Jeanne Duus

    2011-01-01

    Attempts to improve formulation of topical products are a continuing process and the development of micro- and nanovesicular systems as well as polymeric microparticles has led to marketing of topical drugs and cosmetics using these technologies. Encapsulation of some well-known contact allergens...... in ethanolic liposomes have been reported to enhance allergenicity compared with the allergens in similar vehicles without liposomes. The present report includes data on more sensitization studies using the mouse local lymph node assay with three contact allergens encapsulated in different dermal drug...... dichromate compared with control solutions. However, encapsulating the lipophilic contact allergen dinitrochlorobenzene (DNCB) in polycaprolactone reduced the sensitizing capacity to 1211 ± 449 compared with liposomes (7602 ± 2658) and in acetone:olive oil (4:1) (5633 ± 666). The same trend was observed...

  3. Towards electron transport measurements in chemically modified graphene: effect of a solvent

    Energy Technology Data Exchange (ETDEWEB)

    Jacobsen, Arnhild; Ensslin, Klaus [Solid State Physics Laboratory, ETH Zurich (Switzerland); Koehler, Fabian M; Stark, Wendelin J, E-mail: arnhildj@phys.ethz.ch, E-mail: fabian.koehler@chem.ethz.ch [Institute for Chemical and Bioengineering, ETH Zurich (Switzerland)

    2010-12-15

    The chemical functionalization of graphene modifies the local electron density of carbon atoms and hence electron transport. Measuring these changes allows for a closer understanding of the chemical interaction and the influence of functionalization on the graphene lattice. However, not only chemistry, in this case diazonium chemistry, has an effect on electron transport. The latter is also influenced by defects and dopants resulting from different processing steps. Here, we show that the solvents used in the chemical reaction process change the transport properties. In more detail, the investigated combination of isopropanol and heating treatment reduces the doping concentration and significantly increases the mobility of graphene. Furthermore, isopropanol treatment alone increases the concentration of dopants and introduces an asymmetry between electron and hole transport, which might be difficult to distinguish from the effect of functionalization. The results shown in this work demand a closer look at the influence of solvents used for chemical modification in order to understand their influence.

  4. Towards electron transport measurements in chemically modified graphene: effect of a solvent

    International Nuclear Information System (INIS)

    Jacobsen, Arnhild; Ensslin, Klaus; Koehler, Fabian M; Stark, Wendelin J

    2010-01-01

    The chemical functionalization of graphene modifies the local electron density of carbon atoms and hence electron transport. Measuring these changes allows for a closer understanding of the chemical interaction and the influence of functionalization on the graphene lattice. However, not only chemistry, in this case diazonium chemistry, has an effect on electron transport. The latter is also influenced by defects and dopants resulting from different processing steps. Here, we show that the solvents used in the chemical reaction process change the transport properties. In more detail, the investigated combination of isopropanol and heating treatment reduces the doping concentration and significantly increases the mobility of graphene. Furthermore, isopropanol treatment alone increases the concentration of dopants and introduces an asymmetry between electron and hole transport, which might be difficult to distinguish from the effect of functionalization. The results shown in this work demand a closer look at the influence of solvents used for chemical modification in order to understand their influence.

  5. Allergenicity of latex rubber products used in South African dental ...

    African Journals Online (AJOL)

    Fourteen latex examination gloves (powdered and non-powdered) and five dental rubber dams, representing 6 brands, from five dental academic institutions were analysed for latex allergens and total protein. Total protein content was determined using the BioRad DC protein assay kit and natural rubber allergen levels ...

  6. Effect of emulsifiers on complexation and retrogradation characteristics of native and chemically modified White sorghum (Sorghum bicolor) starch

    International Nuclear Information System (INIS)

    Ali, Tahira Mohsin; Hasnain, Abid

    2013-01-01

    Highlights: ► Sorghum starches were chemically modified. ► Starch–lipid complexes were studied in the presence of emulsifiers. ► Type II complexes were also detected in native and oxidized starches on adding GMS. ► Starch–lipid complexes sharply reduced retrogradation in modified starches. - Abstract: The effect of emulsifiers on complexation and retrogradation characteristics of native and chemically modified white sorghum starches was studied. Complex forming tendency of white sorghum starch with commercially available emulsifiers GMS and DATEM improved after acetylation. Presence of emulsifiers reduced λ max (wavelength of maximum absorbance) both for native and modified sorghum starches suggesting lower availability of amylose chains to complex with iodine. In native white sorghum starch (NWSS) and oxidized white sorghum starch (OWSS), both Type I and Type II starch–lipid complexes were observed on addition of 1.0% GMS prior to gelatinization. Acetylated-oxidized white sorghum starch (AOWSS) formed weakest complexes among all the modified starches. The results revealed that antistaling characteristics of modified sorghum starches were enhanced when used in combination with emulsifiers. The most prominent decline in reassociative capability among modified starches was observed for acetylated starches.

  7. Detection of peanut allergen in human blood after consumption of peanuts is skewed by endogenous immunoglobulins

    NARCIS (Netherlands)

    Janssen Duijghuijsen, L.M.; Wichers, H.J.; Norren, van K.; Keijer, J.; Baumert, J.L.; Jong, De Govardus A.H.; Witkamp, R.F.; Koppelman, S.J.

    2017-01-01

    Some studies have suggested that allergens may appear in the circulation after ingestion of allergenic food
    sources. The reported levels of allergen in serum, however, are low, and conclusions between studies differ.
    Here, we investigated factors that determine the detection of allergens in

  8. Detection of peanut allergen in human blood after consumption of peanuts is skewed by endogenous immunoglobulins

    NARCIS (Netherlands)

    Janssen-Duijghuijsen, L.M.; Wichers, H.J.; Norren, K. van; Keijer, J.; Baumert, J.L.; Jong, G.A.H. de; Witkamp, R.F.; Koppelman, S.J.

    2017-01-01

    Some studies have suggested that allergens may appear in the circulation after ingestion of allergenic food sources. The reported levels of allergen in serum, however, are low, and conclusions between studies differ. Here, we investigated factors that determine the detection of allergens in serum

  9. A review of clinical efficacy, safety, new developments and adherence to allergen-specific immunotherapy in patients with allergic rhinitis caused by allergy to ragweed pollen (Ambrosia artemisiifolia).

    Science.gov (United States)

    Turkalj, Mirjana; Banic, Ivana; Anzic, Srdjan Ante

    2017-01-01

    Allergic rhinitis is a common health problem in both children and adults. The number of patients allergic to ragweed ( Ambrosia artemisiifolia ) is on the rise throughout Europe, having a significant negative impact on the patients' and their family's quality of life. Allergen-specific immunotherapy (AIT) has disease-modifying effects and can induce immune tolerance to allergens. Both subcutaneous immunotherapy and sublingual immunotherapy with ragweed extracts/preparations have clear positive clinical efficacy, especially over pharmacological treatment, even years after the treatment has ended. AIT also has very good safety profiles with extremely rare side effects, and the extracts/preparations used in AIT are commonly well tolerated by patients. However, patient adherence to treatment with AIT seems to be quite low, mostly due to the fact that treatment with AIT is relatively time-demanding and, moreover, due to patients not receiving adequate information and education about the treatment before it starts. AIT is undergoing innovations and improvements in clinical efficacy, safety and patient adherence, especially with new approaches using new adjuvants, recombinant or modified allergens, synthetic peptides, novel routes of administration (epidermal or intralymphatic), and new protocols, which might make AIT more acceptable for a wider range of patients and novel indications. Patient education and support (eg, recall systems) is one of the most important goals for AIT in the future, to further enhance treatment success.

  10. Serological response of cattle to Brucella allergen after repeated intradermal applications of this allergen

    NARCIS (Netherlands)

    Muskens, J.A.M.; Bercovich, Z.; Damen, C.P.R.M.

    1996-01-01

    A study was conducted to determine whether an allergen that has been prepared from a mucoid strain of Brucella abortus triggers a serum antibody response that interferes with the interpretation of serologic tests results. Fifteen cattle seronegative for Brucella antigen were tested with the SDTH

  11. A modified parallel artificial membrane permeability assay for evaluating the bioconcentration of highly hydrophobic chemicals in fish.

    Science.gov (United States)

    Kwon, Jung-Hwan; Escher, Beate I

    2008-03-01

    Low cost in vitro tools are needed at the screening stage of assessment of bioaccumulation potential of new and existing chemicals because the number of chemical substances that needs to be tested highly exceeds the capacity of in vivo bioconcentration tests. Thus, the parallel artificial membrane permeability assay (PAMPA) system was modified to predict passive uptake/ elimination rate in fish. To overcome the difficulties associated with low aqueous solubility and high membrane affinity of highly hydrophobic chemicals, we measured the rate of permeation from the donor poly(dimethylsiloxane)(PDMS) disk to the acceptor PDMS disk through aqueous and PDMS membrane boundary layers and term the modified PAMPA system "PDMS-PAMPA". Twenty chemicals were selected for validation of PDMS-PAMPA. The measured permeability is proportional to the passive elimination rate constant in fish and was used to predict the "minimum" in vivo elimination rate constant. The in vivo data were very close to predicted values except for a few polar chemicals and metabolically active chemicals, such as pyrene and benzo[a]pyrene. Thus, PDMS-PAMPA can be an appropriate in vitro system for nonmetabolizable chemicals. Combination with metabolic clearance rates using a battery of metabolic degradation assays would enhance the applicability for metabolizable chemicals.

  12. NUTIRTION LABELLING OF FOOD AND ALLERGEN IN FOOD

    Directory of Open Access Journals (Sweden)

    Jozef Golian

    2012-10-01

    Full Text Available The new regulation introduced mandatory nutrition labelling and ordering food manufacturers provide information on energy and six nutrients: fat, saturated fatty acids, carbohydrates, sugars, protein and salt - in that order, and per 100 g or 100 ml. This information should be included in the nutritional table in one visual field (usually on the back cover, moreover, can also be expressed on per serving. It is important to realize that this regulation requires manufacturers indicate the nutritional value in one field of vision, usually on the "back cover" designation in the principal field (e.g. "on the front cover" remains voluntary. 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 labelling of ‘‘priority allergens. 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 labelling regulations was assembled and analyzed to identify commonalities, differences, and future needs.doi:10.5219/230

  13. The sensory quality of allergen-controlled, fat-reduced, salt-reduced pork-ostrich sausages during storage.

    Science.gov (United States)

    Guzek, Dominika; Głąbska, Dominika; Brodowska, Marta; Godziszewska, Jolanta; Górska-Horczyczak, Elżbieta; Pogorzelska, Ewelina; Wojtasik-Kalinowska, Iwona; Wierzbicka, Agnieszka

    2017-12-01

    New meat products tailored to consumer health should be characterised by reduced sodium, fat and cholesterol contents and other health-promoting benefits. However, the food sector's greatest challenge is allergen-free production. Consumers are not willing to compromise the sensory quality of meat products for health. The aim of the present study was to analyse the influence of the storage time on the physical properties and consumer acceptance of allergen-controlled, fat-reduced, salt-reduced pork-ostrich sausages. The study focused on pork-ostrich sausages produced in accordance with a new patented technology, which focused on eliminating cross-contamination on-line in the plant, eliminating cross-contamination after preparation, and eliminating spices with high allergy potential. The production was focused on reducing fat (by approximately 50%) and salt (by approximately 30%) levels. No changes in the texture parameters of the sausage were observed during storage time; however, some changes in colour were observed. There were no significant differences in sensory consumer acceptability of pork-ostrich sausage after 14 days of storage; thus, it may be stated that the instrumentally assessed differences in colour did not influence consumer acceptance. The applied fat and NaCl reduction in the pork-ostrich sausages contributed to high consumer ratings and was not correlated with saltiness acceptability. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  14. Application of recombinant latex allergens in diagnostics of occupational latex allergy

    Directory of Open Access Journals (Sweden)

    Ewa Nowakowska-Świrta

    2015-02-01

    Full Text Available Over many years, allergy to natural rubber latex has been a major problem among health care workers (HCW. The diagnosis of occupational allergy requires methods of high diagnostic accuracy in view of certification implications (e.g., a sick worker quits a job. With the development of molecular methods, the frequency of application of recombinant allergens in the diagnostics of allergic diseases continues to increase. This paper reviews the applicability of laboratory tests which use recombinant allergens in the diagnostics of occupational allergy. The diagnosis of latex allergy is based on the presence of clinical symptoms linked with exposure to latex allergens, positive skin prick tests and detection of specific IgE antibodies to latex in serum. Moreover, in some cases specific challenge tests are conducted. The analysis of literature indicates that applying the panel of recombinant latex allergens in diagnostic tests, cross-reactivity can very likely be excluded and/or sensitization can be confirmed without the need for specific challenge tests, which in case of latex allergens carries a potential risk of generalized reactions. Med Pr 2015;66(1:85–97

  15. Chemically modified graphite felt as an efficient cathode in electro-Fenton for p-nitrophenol degradation

    International Nuclear Information System (INIS)

    Zhou, Lei; Zhou, Minghua; Hu, Zhongxin; Bi, Zhaoheng; Serrano, K. Groenen

    2014-01-01

    Highlights: • Chemically modified graphite felt was prepared using ethanol and hydrazine hydrate as reagents. • Carbon nanoparticles with functional groups were deposited on the surface after modification. • The electrochemical activity for ORR and H 2 O 2 generation on the modified electrode was improved. • The cathode modification effictively improved the EF performance for pollutant degradation. - Abstract: A simple method with low-cost chemical reagents ethanol and hydrazine hydrate was used to modify graphite felt as the cathode for electro-Fenton (EF) application, using p-nitrophenol (p-Np) as the model pollutant. Characterized by scanning electron microscope, contact angle, Raman spectrum and X-ray photoelectron spectroscopy, the morphology and surface physicochemical properties after modification were observed considerably changed. After modification, some nanoparticles and oxygen and nitrogen-containing functional groups appeared on the cathode surface, which greatly improved the surface hydrophilic property and the electrocatalytic activity for oxygen reduction reaction. The effects led to the hydrogen peroxide accumulation on the modified cathode markedly increased to 175.8 mg L −1 , while that on the unmodified one was only 67.5 mg L −1 . p-Np of initial 50 mg L −1 could be completely removed by EF using the modified cathode, and the mineralization ratio reached 51.4%, more than 2 times of the pristine one. After 10 cycles, the mineralization ratio of the modified cathode was still above 45%, suggesting that the modification method can provide an effective approach to improve EF performance, and thus benefits to promote its environmental applications

  16. Anaphylaxis to Insect Venom Allergens

    DEFF Research Database (Denmark)

    Ollert, Markus; Blank, Simon

    2015-01-01

    available for diagnostic measurement of specific IgE in venom-allergic patients. These recombinant venom allergens offer several promising possibilities for an improved diagnostic algorithm. Reviewed here are the current status, recent developments, and future perspectives of molecular diagnostics of venom...

  17. Effect of local allergen priming on early, late, delayed-phase, and epicutaneous skin reactions

    NARCIS (Netherlands)

    Weller, F. R.; Weller, M. S.; Jansen, H. M.; de Monchy, J. G.

    1996-01-01

    Allergic disease is reflected in a chronic inflammatory response to an allergen. It is thought that local allergen priming underlies this chronicity. To assess the effect of allergen priming on the amplitude and histologic effect of the allergic reaction, four sequential, intracutaneous skin tests

  18. Effect of local allergen priming on early, late, delayed-phase, and epicutaneous skin reactions

    NARCIS (Netherlands)

    Weller, FR; Weller, MS; Jansen, HM; deMonchy, JGR

    1996-01-01

    Allergic disease is renected in a chronic inflammatory response to an allergen. It is thought that local allergen priming underlies this chronicity. To assess the effect of allergen priming on the amplitude and histologic effect of the allergic reaction, four sequential, intracutaneous skin tests

  19. Precautionary labelling of foods for allergen content: are we ready for a global framework?

    Science.gov (United States)

    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

  20. Precautionary labelling of foods for allergen content: are we ready for a global framework?

    Science.gov (United States)

    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.

  1. Screening of transgenic proteins expressed in transgenic food crops for the presence of short amino acid sequences identical to potential, IgE – binding linear epitopes of allergens

    Directory of Open Access Journals (Sweden)

    Peijnenburg Ad ACM

    2002-12-01

    Full Text Available Abstract Background Transgenic proteins expressed by genetically modified food crops are evaluated for their potential allergenic properties prior to marketing, among others by identification of short identical amino acid sequences that occur both in the transgenic protein and allergenic proteins. A strategy is proposed, in which the positive outcomes of the sequence comparison with a minimal length of six amino acids are further screened for the presence of potential linear IgE-epitopes. This double track approach involves the use of literature data on IgE-epitopes and an antigenicity prediction algorithm. Results Thirty-three transgenic proteins have been screened for identities of at least six contiguous amino acids shared with allergenic proteins. Twenty-two transgenic proteins showed positive results of six- or seven-contiguous amino acids length. Only a limited number of identical stretches shared by transgenic proteins (papaya ringspot virus coat protein, acetolactate synthase GH50, and glyphosate oxidoreductase and allergenic proteins could be identified as (part of potential linear epitopes. Conclusion Many transgenic proteins have identical stretches of six or seven amino acids in common with allergenic proteins. Most identical stretches are likely to be false positives. As shown in this study, identical stretches can be further screened for relevance by comparison with linear IgE-binding epitopes described in literature. In the absence of literature data on epitopes, antigenicity prediction by computer aids to select potential antibody binding sites that will need verification of IgE binding by sera binding tests. Finally, the positive outcomes of this approach warrant further clinical testing for potential allergenicity.

  2. Occupational irritant contact dermatitis diagnosed by analysis of contact irritants and allergens in the work environment.

    Science.gov (United States)

    Friis, Ulrik F; Menné, Torkil; Schwensen, Jakob F; Flyvholm, Mari-Ann; Bonde, Jens P E; Johansen, Jeanne D

    2014-12-01

    Irritant contact dermatitis (ICD) is a common diagnosis in patients with occupational contact dermatitis (OCD). Studies are lacking on the usefulness of material safety data sheets (MSDSs) in making the diagnosis of ICD. To characterize irritant exposures leading to the diagnosis of occupational ICD (OICD), and to evaluate the occurrence of concomitant exposures to contact allergens. We included 316 patients with suspected occupational hand dermatitis, referred to the Department of Dermato-Allergology, Copenhagen University Hospital Gentofte, Denmark during January 2010-August 2011, in a programme consisting of a clinical examination, exposure assessment, and extensive patch/prick testing. OCD was diagnosed in 228 patients. Of these patients, 118 were diagnosed with OICD. The main irritant exposures identified were wet work (n = 64), gloves (n = 45), mechanical traumas (n = 19), and oils (n = 15). Exposure to specific irritant chemicals was found in 9 patients, and was identified from MSDSs/ingredients labelling in 8 of these patients. Review of MSDSs and ingredients labelling showed that 41 patients were exposed to 41 moderate to potent contact allergens, and 18 patients were exposed to 25 weak workplace contact allergens. In the present study, the systematic exposure assessment did not reveal any new irritants. MSDSs have a limited role in the investigation of ICD. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. Encapsulating contact allergens in liposomes, ethosomes, and polycaprolactone may affect their sensitizing properties

    DEFF Research Database (Denmark)

    Madsen, Jakob Torp; Vogel, Stefan; Johansen, Jeanne Duus

    2011-01-01

    Attempts to improve formulation of topical products are a continuing process and the development of micro- and nanovesicular systems as well as polymeric microparticles has led to marketing of topical drugs and cosmetics using these technologies. Encapsulation of some well-known contact allergens...... in ethanolic liposomes have been reported to enhance allergenicity compared with the allergens in similar vehicles without liposomes. The present report includes data on more sensitization studies using the mouse local lymph node assay with three contact allergens encapsulated in different dermal drug...... dichromate compared with control solutions. However, encapsulating the lipophilic contact allergen dinitrochlorobenzene (DNCB) in polycaprolactone reduced the sensitizing capacity to 1211 ± 449 compared with liposomes (7602 ± 2658) and in acetone:olive oil (4:1) (5633 ± 666). The same trend was observed...

  4. Selected oxidized fragrance terpenes are common contact allergens

    DEFF Research Database (Denmark)

    Matura, Mihaly; Sköld, Maria; Börje, Anna

    2005-01-01

    Terpenes are widely used fragrance compounds in fine fragrances, but also in domestic and occupational products. Terpenes oxidize easily due to autoxidation on air exposure. Previous studies have shown that limonene, linalool and caryophyllene are not allergenic themselves but readily form...... allergenic products on air-exposure. This study aimed to determine the frequency and characteristics of allergic reactions to selected oxidized fragrance terpenes other than limonene. In total 1511 consecutive dermatitis patients in 6 European dermatology centres were patch tested with oxidized fragrance...

  5. Allergenicity and cross-reactivity of booklice (Liposcelis bostrichophila): a common household insect pest in Japan.

    Science.gov (United States)

    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.

  6. Allergen recognition by innate immune cells: critical role of dendritic and epithelial cells

    Directory of Open Access Journals (Sweden)

    Fabian eSalazar

    2013-11-01

    Full Text Available Allergy is an exacerbated response of the immune system against non-self-proteins called allergens and is typically characterized by biased type-2 T helper cell and deleterious IgE mediated immune responses. The allergic cascade starts with the recognition of allergens by antigen presenting cells, mainly dendritic cells, culminating in mast cell sensitization and triggering. Dendritic cells have been demonstrated to play a crucial role in orchestrating allergic diseases. Using different C-type lectin receptors dendritic cells are able to recognize and internalize a number of allergens from diverse sources leading to sensitization. Furthermore, there is increasing evidence highlighting the role of epithelial cells in triggering and modulating immune responses to allergens. As well as providing a physical barrier, epithelial cells can interact with allergens and influence dendritic cells behaviour through the release of a number of Th2 promoting cytokines. In this review we will summarise current understanding of how allergens are recognised by dendritic cells and epithelial cells and what are the consequences of such interaction in the context of allergic sensitisation and downstream events leading to allergic inflammation. Better understanding of the molecular mechanisms of allergen recognition and associated signalling pathways could enable developing more effective therapeutic strategies that target the initial steps of allergic sensitisation hence hindering development or progression of allergic diseases.

  7. Chloroatranol, an extremely potent allergen hidden in perfumes

    DEFF Research Database (Denmark)

    Johansen, Jeanne Duus; Andersen, Klaus Ejner; Svedman, Cecilia

    2003-01-01

    Oak moss absolute is a long-known, popular natural extract widely used in perfumes. It is reported as the cause of allergic reactions in a significant number of those with perfume allergy. Oak moss absolute has been the target of recent research to identify its allergenic components. Recently...... an open test simulating the use of perfumes on the volar aspect of the forearms in a randomized and double-blinded design. A solution with 5 p.p.m. chloroatranol was used for 14 days, and, in case of no reaction, the applications were continued for another 14 days with a solution containing 25 p.p.m. All....... The dose eliciting a reaction in 50% of the test subjects at patch testing was 0.2 p.p.m. In conclusion, the hidden exposure to a potent allergen widely used in perfumes has caused a highly sensitized cohort of individuals. Judged from the elicitation profile, chloroatranol is the most potent allergen...

  8. Allergen management in the food industry

    National Research Council Canada - National Science Library

    Boye, Joyce I; Godefroy, Samuel Benrejeb

    2010-01-01

    "This book comprehensively addresses the sources of allergenic contaminants in foods, their fate during processing, and the specific measures that need to be taken to minimize their occurrence in foods...

  9. Identification of enolases and aldolases as important fish allergens in cod, salmon and tuna: component resolved diagnosis using parvalbumin and the new allergens.

    Science.gov (United States)

    Kuehn, A; Hilger, C; Lehners-Weber, C; Codreanu-Morel, F; Morisset, M; Metz-Favre, C; Pauli, G; de Blay, F; Revets, D; Muller, C P; Vogel, L; Vieths, S; Hentges, F

    2013-07-01

    The majority of fish-allergic patients are sensitized to parvalbumin, known to be the cause of important IgE cross-reactivity among fish species. Little is known about the importance of fish allergens other than parvalbumin. The aim of this study was to characterize hitherto undefined fish allergens in three commonly consumed fish species, cod, salmon and tuna, and to evaluate their importance for in vitro IgE-diagnosis in addition to parvalbumin and fish gelatin. Sixty-two patients were diagnosed by clinical history, skin prick tests and specific IgE to fish extracts. Two new fish allergens from cod, salmon and tuna were identified by microsequencing. These proteins were characterized by immunoblot, ELISA and mediator release assay. Purified parvalbumin, enolase, aldolase and fish gelatin were used for quantification of specific IgE in ELISA. Parvalbumin and two other allergens of 50 and 40 kDa were detected in IgE-immunoblots of cod, salmon and tuna extracts by most patient sera. The 50 and 40 kDa proteins were identified as beta-enolase and fructose-bisphosphate aldolase A respectively. Both purified enzymes showed allergenic activity in the mediator release assay. Indeed, 72.6% of the patients were sensitized to parvalbumin, 20% of these had specific IgE to salmon parvalbumin only. IgE to enolases were found in 62.9% (0.5-95.0 kUA /L), to aldolases in 50.0% (0.4-26.0 kUA /L) and to fish gelatin in 19.3% (0.4-20.0 kUA /L) of the patients. Inter-species cross-reactivity, even though limited, was found for enolases and aldolases by IgE-inhibition ELISA. Fish enolase and aldolase have been identified as important new fish allergens. In fish allergy diagnosis, IgE to enolase and aldolase are especially relevant when IgE to parvalbumin are absent. © 2013 John Wiley & Sons Ltd.

  10. Consumer-friendly food allergen detection

    NARCIS (Netherlands)

    Ross, Georgina M.S.; Bremer, Monique G.E.G.; Nielen, Michel W.F.

    2018-01-01

    In this critical review, we provide a comprehensive overview of immunochemical food allergen assays and detectors in the context of their user-friendliness, through their connection to smartphones. Smartphone-based analysis is centered around citizen science, putting analysis into the hands of the

  11. Allergen immunotherapy for allergic rhinoconjunctivitis

    DEFF Research Database (Denmark)

    Dhami, Sangeeta; Nurmatov, Ulugbek; Roberts, Graham

    2016-01-01

    BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines for Allergen Immunotherapy (AIT) for the Management of Allergic Rhinoconjunctivitis. We seek to critically assess the effectiveness, cost-effectiveness and safety of AIT...

  12. Allergenic Proteins in Enology: A Review on Technological Applications and Safety Aspects

    Directory of Open Access Journals (Sweden)

    Elena Peñas

    2015-07-01

    Full Text Available Proteinaceous products are widely used as fining agents during winemaking to remove unwanted insoluble particles and undissolved microscopic particles (colloidal material from the must or wine to improve stability. Some of them (egg white, caseinates, and fish gelatine have allergenic potential and the presence of their residues in the final product could represent a risk for allergic individuals. Moreover, lysozyme (an egg allergen is included among wine additives to control the fermentation processes and avoid spoiling during winemaking. The aim of this paper is to review the experimental/clinical data on the use of allergenic products in enology and the measurement of relative risk for sensitized subjects. In addition, methods developed specifically for the quantification of allergenic residues in must and wine are described.

  13. Assessment of the risk of respiratory sensitization from fragrance allergens released by air fresheners.

    Science.gov (United States)

    ter Burg, Wouter; Bouma, Krista; Schakel, Durk J; Wijnhoven, Susan W P; van Engelen, Jacqueline; van Loveren, Henk; Ezendam, Janine

    2014-04-01

    Consumers using air fresheners are exposed to the emitted ingredients, including fragrances, via the respiratory tract. Several fragrances are known skin sensitizers, but it is unknown whether inhalation exposure to these chemicals can induce respiratory sensitization. Effects on the immune system were assessed by testing a selection of five fragrance allergens in the respiratory local lymph node assay (LLNA). The probability and extent of exposure were assessed by measuring concentrations of the 24 known fragrance allergens in 109 air fresheners. It was shown that the most frequently used fragrances in air fresheners were D-limonene and linalool. In the respiratory LLNA, these fragrances were negative. Of the other tested chemicals, only isoeugenol induced a statistically significant increase in cell proliferation. Consumer exposure was assessed in more detail for D-limonene, linalool, and isoeugenol by using exposure modeling tools. It was shown that the most frequently used fragrances in air fresheners, D-limonene, and linalool gave rise to a higher consumer exposure compared with isoeugenol. To evaluate whether the consumer exposure to these fragrances is low or high, these levels were compared with measured air concentrations of diisocyanates, known human respiratory sensitizers. This comparison showed that consumer exposure from air fresheners to D-limonene, linalool, and isoeugenol is considerably lower than occupational exposure to diisocyanates. By combing this knowledge on sensitizing potency with the much lower exposure compared to diisocyanates it seems highly unlikely that isoeugenol can induce respiratory sensitization in consumers using air fresheners.

  14. Fluorescence spectroscopic investigation of the interaction of citrinin with native and chemically modified cyclodextrins

    Energy Technology Data Exchange (ETDEWEB)

    Poór, Miklós, E-mail: poor.miklos@pte.hu [Department of Pharmacology and Pharmacotherapy, Toxicology Section, University of Pécs, Szigeti út 12, Pécs H-7624 (Hungary); Matisz, Gergely; Kunsági-Máté, Sándor [Department of General and Physical Chemistry, University of Pécs, Ifjúság útja 6, Pécs H-7624 (Hungary); János Szentágothai Research Center, Ifjúság útja 20, Pécs H-7624 (Hungary); Derdák, Diána [Department of General and Physical Chemistry, University of Pécs, Ifjúság útja 6, Pécs H-7624 (Hungary); Szente, Lajos [CycloLab Cyclodextrin Research & Development Laboratory Ltd., Illatos út 7, Budapest H-1097 (Hungary); and others

    2016-04-15

    Citrinin (CIT) is a nephrotoxic mycotoxin produced by several Aspergillus, Penicillium and Monascus species. CIT is unavoidable contaminant of different foods and drinks due to its wide occurrence and high thermal stability. For this reason, development of new, more sensitive analytical methods and decontamination strategies has high importance. In our study, the complex formation of CIT with native and chemically modified cyclodextrins was investigated using fluorescence spectroscopy. Furthermore, thermodynamic and molecular modeling studies were also performed for the deeper understanding of these host-guest interactions. Our results show that among the tested compounds methylated β-cyclodextrins form the most stable complexes with CIT and these derivatives cause the highest fluorescence enhancement of CIT as well. These observations recommend that some of the chemically modified derivatives show more favourable properties than the native cyclodextrin, and suggesting more promising analytical applicability and higher affinity as potential toxin binders.

  15. Risk assessment and food allergy: the probabilistic model applied to allergens

    NARCIS (Netherlands)

    Spanjersberg, M.Q.I.; Kruizinga, A.G.; Rennen, M.A.J.; Houben, G.F.

    2007-01-01

    In order to assess the risk of unintended exposure to food allergens, traditional deterministic risk assessment is usually applied, leading to inconsequential conclusions as 'an allergic reaction cannot be excluded'. TNO therefore developed a quantitative risk assessment model for allergens based on

  16. Treatment with grass allergen peptides improves symptoms of grass pollen-induced allergic rhinoconjunctivitis.

    Science.gov (United States)

    Ellis, Anne K; Frankish, Charles W; O'Hehir, Robyn E; Armstrong, Kristen; Steacy, Lisa; Larché, Mark; Hafner, Roderick P

    2017-08-01

    Synthetic peptide immunoregulatory epitopes are a new class of immunotherapy to treat allergic rhinoconjunctivitis (ARC). Grass allergen peptides, comprising 7 synthetic T-cell epitopes derived from Cyn d 1, Lol p 5, Dac g 5, Hol l 5, and Phl p 5, is investigated for treatment of grass pollen-induced ARC. We sought to evaluate the efficacy, safety, and tolerability of intradermally administered grass allergen peptides. A multicenter, randomized, double-blind, placebo-controlled study evaluated 3 regimens of grass allergen peptides versus placebo in patients with grass pollen-induced allergy (18-65 years). After a 4-day baseline challenge to rye grass in the environmental exposure unit (EEU), subjects were randomized to receive grass allergen peptides at 6 nmol at 2-week intervals for a total of 8 doses (8x6Q2W), grass allergen peptides at 12 nmol at 4-week intervals for a total of 4 doses (4x12Q4W), or grass allergen peptides at 12 nmol at 2-week intervals for a total of 8 doses (8x12Q2W) or placebo and treated before the grass pollen season. The primary efficacy end point was change from baseline in total rhinoconjunctivitis symptom score across days 2 to 4 of a 4-day posttreatment challenge (PTC) in the EEU after the grass pollen season. Secondary efficacy end points and safety were also assessed. Two hundred eighty-two subjects were randomized. Significantly greater improvement (reduction of total rhinoconjunctivitis symptom score from baseline to PTC) occurred across days 2 to 4 with grass allergen peptide 8x6Q2W versus placebo (-5.4 vs -3.8, respectively; P = .0346). Greater improvement at PTC also occurred for grass allergen peptide 8x6Q2W versus placebo (P = .0403) in patients with more symptomatic ARC. No safety signals were detected. Grass allergen peptide 8x6Q2W significantly improved ARC symptoms after rye grass allergen challenge in an EEU with an acceptable safety profile. Copyright © 2017 American Academy of Allergy, Asthma & Immunology

  17. Evaluation of molecular basis of cross reactivity between rye and Bermuda grass pollen allergens.

    Science.gov (United States)

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

    2009-12-01

    Allergenic cross reactivity between the members of the Pooids (Lolium perenne, Phleum pratense, and Poa pratensis) and Chloridoids (Cynodon dactylon and Paspalum notatum) is well established. Studies using crude extracts in the past have demonstrated limited cross reactivity between the Pooids and the Chloridoids suggesting separate diagnosis and therapy. However, little is known regarding the molecular basis for the limited cross reactivity observed between the 2 groups of grasses. The present study was undertaken to gain insights into the molecular basis of cross allergenicity between the major allergens from rye and Bermuda grass pollens. Immunoblot inhibition tests were carried out to determine the specificity of the proteins involved in cross reactivity. Crude pollen extract and bacterially expressed and purified recombinant Lol p 1and Lol p 5 from rye grass were subjected to cross inhibition experiments with crude and purified recombinant Cyn d 1 from Bermuda grass using sera from patients allergic to rye grass pollen. The immunoblot inhibition studies revealed a high degree of cross inhibition between the group 1 allergens. In contrast, a complete lack of inhibition was observed between Bermuda grass group 1 allergen rCyn d 1, and rye grass group 5 allergen rLol p 5. Crude rye grass extract strongly inhibited IgE reactivity to Bermuda grass, whereas crude Bermuda grass pollen extract showed a weaker inhibition. Our data suggests that a possible explanation for the limited cross reactivity between the Pooids and Chloridoids may, in part, be due to the absence of group 5 allergen from Chloridoid grasses. This approach of using purified proteins may be applied to better characterize the cross allergenicity patterns between different grass pollen allergens.

  18. American Contact Dermatitis Society Core Allergen Series: 2017 Update.

    Science.gov (United States)

    Schalock, Peter C; Dunnick, Cory A; Nedorost, Susan; Brod, Bruce; Warshaw, Erin; Mowad, Christen

    The American Contact Dermatitis Society Core Allergen Series was introduced in 2012. After 4 years of use, changes in our recommended allergens are necessary. For the updated series, we have reordered the first 4 panels to approximately mirror the current TRUE Test and removed parthenolide, triclosan, glutaraldehyde, and jasmine. Polymyxin B, lavender, sodium benzoate, ethylhexylglycerin, and benzoic acid are new additions to the American Contact Dermatitis Society series.

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

    Science.gov (United States)

    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.

  20. Vagal afferents contribute to exacerbated airway responses following ozone and allergen challenge.

    Science.gov (United States)

    Schelegle, Edward S; Walby, William F

    2012-05-31

    Brown-Norway rats (n=113) sensitized and challenged with nDer f 1 allergen were used to examine the contribution of lung sensory nerves to ozone (O(3)) exacerbation of asthma. Prior to their third challenge rats inhaled 1.0ppm O(3) for 8h. There were three groups: (1) control; (2) vagus perineural capsaicin treatment (PCT) with or without hexamethonium; and (3) vagotomy. O(3) inhalation resulted in a significant increase in lung resistance (R(L)) and an exaggerated response to subsequent allergen challenge. PCT abolished the O(3)-induced increase in R(L) and significantly reduced the increase in R(L) induced by a subsequent allergen challenge, while hexamethonium treatment reestablished bronchoconstriction induced by allergen challenge. Vagotomy resulted in a significant increase in the bronchoconstriction induced by O(3) inhalation and subsequent challenge with allergen. In this model of O(3) exacerbation of asthma, vagal C-fibers initiate reflex bronchoconstriction, vagal myelinated fibers initiate reflex bronchodilation, and mediators released within the airway initiate bronchoconstriction. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Allergen-specific immunotherapy and risk of autoimmune disease

    DEFF Research Database (Denmark)

    Linneberg, Allan; Madsen, Flemming; Skaaby, Tea

    2012-01-01

    After 100 years of experience with allergen-specific immunotherapy (SIT), an issue that is still unresolved is whether SIT can act as a trigger of, or as a risk factor for, autoimmune disease. We searched the literature for evidence on this topic.......After 100 years of experience with allergen-specific immunotherapy (SIT), an issue that is still unresolved is whether SIT can act as a trigger of, or as a risk factor for, autoimmune disease. We searched the literature for evidence on this topic....

  2. Allergen immunotherapy for the prevention of allergic disease

    DEFF Research Database (Denmark)

    Dhami, Sangeeta; Nurmatov, Ulugbek; Halken, Susanne

    2016-01-01

    BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines for Allergen Immunotherapy (AIT) for the Prevention of Allergic Disease. We seek to critically assess the effectiveness, cost-effectiveness and safety of AIT in the pre......BACKGROUND: The European Academy of Allergy and Clinical Immunology (EAACI) is in the process of developing the EAACI Guidelines for Allergen Immunotherapy (AIT) for the Prevention of Allergic Disease. We seek to critically assess the effectiveness, cost-effectiveness and safety of AIT...

  3. Clinical relevance is associated with allergen-specific wheal size in skin prick testing

    DEFF Research Database (Denmark)

    Haahtela, T.; Burbach, G. J.; Bachert, C.

    2014-01-01

    , 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. ResultsDepending on the allergen, from 40% (blatella...... by providing quantitative decision points. MethodsThe 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...... SPT reactions had a smaller risk of sensitizations being clinically relevant compared with adults. The 80% PPV varied from 3 to 10mm depending on the allergen. ConclusionThese reading keys' for 18 inhalant allergens can help interpret SPT results with respect to their clinical significance. A SPT form...

  4. Current insights in allergen immunotherapy.

    Science.gov (United States)

    Passalacqua, Giovanni; Bagnasco, Diego; Ferrando, Matteo; Heffler, Enrico; Puggioni, Francesca; Canonica, Giorgio Walter

    2018-02-01

    Allergen-specific immunotherapy (AIT) in its subcutaneous and sublingual forms is currently a well-established and experimentally supported treatment for respiratory allergy and hymenoptera venom allergy. There have been advances in its use linked strictly to the advancement in the knowledge of the molecular mechanisms of allergy, the production of well-characterized extracts, and diagnostic techniques. The use of AIT in asthma and the application of new approaches are expanding. We briefly review the advances and concerns in the use of AIT. PubMed and Scopus. The most recent and clinically relevant literature was selected and reviewed. The introduction of high-quality products supported by large dose-finding trials has yielded better defined indications, contraindications, and modalities of use. Some specific products in tablet form have recently been approved in the United States. Sublingual immunotherapy has been found to be effective in asthma, which until recently had been a matter of debate. Another promising therapy is oral and sublingual desensitization for food allergy, for which encouraging results have recently been reported. In the near future, other options will be available, including new routes of administration (intralymphatic and epicutaneous), allergoids, engineered allergens, and peptides. The use of component-resolved diagnosis techniques will further refine and target AIT prescriptions. This condensed and updated review shows that AIT remains a viable treatment option, especially after the introduction of standardized tablets for some allergens. Food allergy and new administration routes represent a promising expansion. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  5. Assessment of airborne soy-hull allergen (Gly m 1) in the Port of Ancona, Italy.

    Science.gov (United States)

    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.

  6. Airborne study of grass allergen (Lol p 1) in different-sized particles.

    Science.gov (United States)

    De Linares, C; Díaz de la Guardia, C; Nieto Lugilde, D; Alba, F

    2010-01-01

    The Poaceae family is considered one of the main causes of pollen allergy in industrialized countries. The aim of this study is to establish the dynamics of the Poaceae allergens and determine their distribution in the different-sized particles in the atmosphere. The air of Granada (southern Spain) was sampled during the pollination period of Poaceae using a cascade impactor and a Hirst-type volumetric collector simultaneously. The sampled airborne allergens were analyzed by indirect ELISA and field emission scanning electron microscopy. Airborne pollen was evaluated with the Spanish Aerobiological Network methodology. Poaceae pollen and allergenic activity have parallel dynamics during the period of maximum pollination, which is reflected in the positive correlations between the 2 variables. In addition, the highest Lol p 1 concentrations were recorded in particle sizes lower than 3.3 mum (stage 4-F). The Spearman correlation test showed that airborne allergens are not dependent on meteorological factors, such as humidity, wind direction or sunshine, however, Lol p 1 allergen correlated positively with Poaceae pollen. The results of the present study confirm that the Lol p 1 allergen is detected more frequently with pollutants than with coarse particles with similar dynamics and a positive correlation between airborne pollen and aeroallergens. Moreover, Lol p 1 is released in stable weather conditions without large changes in humidity or temperature. Copyright 2009 S. Karger AG, Basel.

  7. Mapping of Lol p I allergenic epitopes by using murine monoclonal antibodies.

    Science.gov (United States)

    Mourad, W; Bernier, D; Jobin, M; Hébert, J

    1989-11-01

    Murine monoclonal antibodies (MAbs) against three non-overlapping epitopes of Lol p I allergen were previously produced and subsequently used for purification of the allergen. In the present study, these MAbs were further characterized, and the biological activity of the purified allergen assessed. The three MAbs were of the IgG isotype and carried a kappa light chain. Their affinity constants were in the range of 7.4-15.1 x 10(-9) mol/l. Purified Lol p I kept its biological activity, as shown by its ability to induce histamine release by basophils of Lol p I-sensitive patients. The profiles of histamine release induced by either Lol p I or crude Lolium perenne extracts were comparable. This observation suggests that human IgE bound to basophils are polyspecific which has been confirmed by immunoblot and inhibition assay. Our data indicated also that Lol p I possesses a major allergenic epitope recognized by all human serum IgE tested. This epitope seems to be partially shared by those recognized by the three MAbs. Finally, preincubation of Lol p I with either one of the Mabs did not affect significantly the basophil-histamine release induced by the purified allergen. This suggests that Lol p I possesses allergenic sites other than the one shared by MAbs and IgE Abs.

  8. Allergenic Ingredients in Personal Hygiene Wet Wipes.

    Science.gov (United States)

    Aschenbeck, Kelly A; Warshaw, Erin M

    Wet wipes are a significant allergen source for anogenital allergic contact dermatitis. The aim of the study was to calculate the frequency of potentially allergenic ingredients in personal hygiene wet wipes. Ingredient lists from brand name and generic personal hygiene wet wipes from 4 large retailers were compiled. In the 54 personal hygiene wet wipes evaluated, a total of 132 ingredients were identified (average of 11.9 ingredients per wipe). The most common ingredients were Aloe barbadensis (77.8%), citric acid (77.8%), fragrance (72.2%), sorbic acid derivatives (63.0%), tocopherol derivatives (63.0%), glycerin (59.3%), phenoxyethanol (55.6%), disodium cocoamphodiacetate (53.7%), disodium ethylenediaminetetraacetic acid (EDTA) (42.6%), propylene glycol (42.6%), iodopropynyl butylcarbamate (40.7%), chamomile extracts (38.9%), sodium benzoate (35.2%), bronopol (22.2%), sodium citrate (22.2%), lanolin derivatives (20.4%), parabens (20.4%), polyethylene glycol derivatives (18.5%), disodium phosphate (16.7%), dimethylol dimethyl hydantoin (DMDM) (14.8%), and cocamidopropyl propylene glycol (PG)-dimonium chloride phosphate (11.1%). Of note, methylisothiazolinone (5.6%) was uncommon; methylchloroisothiazolinone was not identified in the personal hygiene wet wipes examined. There are many potential allergens in personal hygiene wet wipes, especially fragrance and preservatives.

  9. High concentrations of natural rubber latex allergens in gloves used ...

    African Journals Online (AJOL)

    Introduction. Gloves made of natural rubber latex (NRL) are commonly used by healthcare workers because of their good qualities. However, allergic reactions to latex allergens are still commonly reported. Objective. To measure the concentrations of Hev b 1, Hev b 3, Hev b 5 and Hev b 6.02 allergens in gloves used by a ...

  10. Purification and characterisation of relevant natural and recombinant apple allergens

    NARCIS (Netherlands)

    Oberhuber, Christina; Ma, Yan; Marsh, Justin; Rigby, Neil; Smole, Ursula; Radauer, Christian; Alessandri, Stefano; Briza, Peter; Zuidmeer, Laurian; Maderegger, Bernhard; Himly, Martin; Sancho, Ana I.; van Ree, Ronald; Knulst, André; Ebner, Christof; Shewry, Peter; Mills, E. N. Clare; Wellner, Klaus; Breiteneder, Heimo; Hoffmann-Sommergruber, Karin; Bublin, Merima

    2008-01-01

    Apple (Malus domestica) is the most widely cultivated fruit crop in Europe and frequently causes allergic reactions with a variable degree of severity. So far, four apple allergens Mal d 1, Mal d 2, Mal d 3 and Mal d 4 have been identified. Mal d 1, a Bet v 1 related allergen, and Mal d 4, apple

  11. EAACI Guidelines on Allergen Immunotherapy

    DEFF Research Database (Denmark)

    Roberts, G; Pfaar, O; Akdis, C A

    2018-01-01

    Allergic rhinoconjunctivitis (AR) is an allergic disorder of the nose and eyes affecting about a fifth of the general population. Symptoms of AR can be controlled with allergen avoidance measures and pharmacotherapy. However, many patients continue to have ongoing symptoms and an impaired quality...

  12. Molecular cloning, expression and characterization of Pru a 1, the major cherry allergen.

    Science.gov (United States)

    Scheurer, S; Metzner, K; Haustein, D; Vieths, S

    1997-06-01

    A high percentage of birch pollen allergic patients experiences food hypersensitivity reactions after ingestion of several fruits and vegetables. Previous work demonstrated common epitopes on an allergen of Mr 18,000 from sweet cherry (Prunus avium) and Bet v 1, the major allergen from birch pollen. N-terminal amino acid sequencing showed a sequence identity of 67% with Bet v 1. Here we report the cloning and cDNA sequencing of this cherry allergen. The entire deduced amino acid sequence described a protein of Mr 17,700 with 59.1% identity to Bet v 1. High degrees of identity in the range of 40 to 60% were also found with related allergens from other kinds of tree pollen and plant foods as well as with stress-induced proteins from food plants such as parsley, potato and soya. The coding DNA of the cherry protein was cloned into vector pET-16b and expressed in E. coli strain BL21(DE3) as a His-tag fusion protein. As shown by SDS-PAGE, the apparent molecular masses of the nonfusion protein and the natural allergen were identical. The fusion protein showed high IgE binding potency when sera from patients allergic to cherry were tested by immunoblotting and enzyme allergosorbent tests. Moreover, it cross-reacted strongly with IgE specific for the natural counterpart and for Bet v 1. The high biological activity of the recombinant fusion protein was further confirmed by the induction of a strong histamine release in basophils from cherry-allergic patients. Since sera from 17/19 of such patients contained IgE against this allergen it was classified as a major allergen and named Pru a 1. Recombinant Pru a 1 mimics most of the allergenic potency of cherry extract and hence could be a useful tool for studying the molecular and immunological properties of pollen related food allergens.

  13. Current glimpse of airborne allergenic pollen in Indian subcontinent

    Directory of Open Access Journals (Sweden)

    Kavita Ghosal

    2015-12-01

    Full Text Available Respiratory allergic diseases such as bronchial asthma, rhinitis, urticaria, atopic dermatitis have been steadily increasing all over the world, including India. Owing to its alarming trend, several aerobiological surveys have been undertaken in different parts of India to delineate the variety of pollen and spore load. In this review, we have reported the current state of aerobiological knowladge in India with particular reference to allergenic airborn pollen occurence in 2001–2015. Pollen have been found to contribute a significant proportion in the air and caused allergy symptoms in the local inhabitants. Aerobiological records, a questionnaire survey and hospitalization records have been employed for the analysis. Holoptelea integrifolia, Amaranthus spinosus in northern region, Sorghum vulgare, Pennisetum, Gynandropsis gynandra, Parthenium hysterophorus, Dolichandrone platycalyx in southern regions, and Parthenium hysterophorus from the western region; Cynodon dactylon, Cenchrus ciliaris in the central area; Acacia auriculiformis, Cleome gynandra, Catharanthus roseus, Phoenix sylvestris, Areca catechu, and Lantana camara in the eastern regions as potential aeroallergens in India. The statistical approach confirmed the correlation between hospitalization rate associated with allergy-related health troubles and the prevalent allergenic pollen in the air. The Poaceae group has been found to be dominant throughout India. Immuno-biochemical studies identified various protein with allergenic potential found in the pollen recorded. Epitope identification and homology of the major allergenic protein Cat r1 of Catharanthus sp and Par j 1 of Parietaria judaica have been found. Identification of allergenic pollen grains and the modern approach concerning cross-reactivity and epitope revelation of dominant airborne pollen have important clinical implications for the prevention, diagnosis and treatments of allergic diseases in India.

  14. Repeated allergen exposure reduce early phase airway response and leukotriene release despite upregulation of 5-lipoxygenase pathways

    Directory of Open Access Journals (Sweden)

    Cui Zhi-Hua

    2012-03-01

    Full Text Available Abstract Background Allergen induced early phase airway response and airway plasma exudation are predominantly mediated by inflammatory mast cell mediators including histamine, cysteinyl leukotrienes (cysLTs and thromboxane A2 (TXA2. The aim of the present study was to evaluate whether repeated allergen exposure affects early phase airway response to allergen challenge. Methods A trimellitic anhydride (TMA sensitized guinea pig model was used to investigate the effects of low dose repeated allergen exposure on cholinergic airway responsiveness, early phase airway response and plasma exudation, as well as local airway production of mast cell derived cysteinyl leukotrienes and thromboxane B2 (TXB2 after allergen challenge. Results Repeated low dose allergen exposure increased cholinergic airway responsiveness. In contrast, early phase airway response and plasma exudation in response to a high-dose allergen challenge were strongly attenuated after repeated low dose allergen exposure. Inhibition of the airway response was unspecific to exposed allergen and independent of histamine receptor blocking. Furthermore, a significant reduction of cysteinyl leukotrienes and TXB2 was found in the airways of animals repeatedly exposed to a low dose allergen. However, in vitro stimulation of airway tissue from animals repeatedly exposed to a low dose allergen with arachidonic acid and calcium ionophore (A23187 induced production of cysteinyl leukotrienes and TXB2, suggesting enhanced activity of 5-lipoxygenase and cyclooxygenase pathways. Conclusions The inhibition of the early phase airway response, cysteinyl leukotriene and TXB2 production after repeated allergen exposure may result from unresponsive effector cells.

  15. Production of recombinant peanut allergen Ara h 2 using Lactococcus lactis

    DEFF Research Database (Denmark)

    Glenting, J.; Poulsen, Lars K.; Kato, K.

    2007-01-01

    lactis is an attractive microorganism for use in the production of protein therapeutics. L. lactis is considered food grade, free of endotoxins, and is able to secrete the heterologous product together with few other native proteins. Hypersensitivity to peanut represents a serious allergic problem. Some...... of the major allergens in peanut have been described. However, for therapeutic usage more information about the individual allergenic components is needed. In this paper we report recombinant production of the Ara h 2 peanut allergen using L. lactis. Results: A synthetic ara h 2 gene was cloned into an L...

  16. A clinically relevant major cross-reactive allergen from mesquite tree pollen.

    Science.gov (United States)

    Dhyani, A; Singh, B P; Arora, N; Jain, V K; Sridhara, S

    2008-10-01

    Prosopis juliflora (mesquite) is one of the major sources of pollinosis in tropical and semi-arid countries of the world. The present study was undertaken to purify and characterize a major cross-reactive allergen from this tree species. Mesquite pollen extract was purified using reverse-phase chromatography. Allergen characterization was done by electrophoresis, enzyme-linked immunosorbent assay (ELISA) and Western blotting. Clinical relevance of the purified protein was analyzed by in vivo (skin tests) and in vitro experiments such as ELISA, histamine release, peripheral blood mononuclear cells (PBMC) proliferation and cytokine assays. Cross-reactivity of purified protein with allergenic tree species and lima bean (food) was assessed by inhibition assays. A 66-kDa protein was purified from mesquite pollen extract using octadecyl silica resin. Purified protein recognized 90% of mesquite-sensitized patients in skin test and ELISA. It induced significant histamine release in allergic patients' blood and interleukin-4 secretion in the PBMC culture supernatants. Inhibition assays suggested close allergenic relationship of this protein with Ailanthus excelsa, Cassia siamea, Salvadora persica pollen and Phaseolus lunatus (lima bean - an edible legume). A 66-kDa major cross-reactive allergen was isolated from mesquite pollen using single-step purification procedure. The protein seems relevant for clinical applications in allergic disorders.

  17. Sensitization to allergens of domestic animals

    Directory of Open Access Journals (Sweden)

    A. N. Pampura

    2018-01-01

    Full Text Available At present, sensitization to airborne allergens in domestic animals is absolutely rightly considered one of the key risk factors for the development of allergic rhinitis and bronchial asthma, as well as largely determines the development of severe forms of atopic dermatitis and respiratory allergosis. Of particularimportance isthe fact that, unlike othertriggers, the elimination of allergensin domestic animals is often associated with internal resistance from patients. The article presents the current data on the prevalence of sensitization, the properties and clinical significance of the main allergens of cats and dogs, outlines approaches to conducting elimination activities.

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

    Science.gov (United States)

    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.

  19. A proteomic study to identify soya allergens--the human response to transgenic versus non-transgenic soya samples.

    Science.gov (United States)

    Batista, Rita; Martins, Isabel; Jeno, Paul; Ricardo, Cândido Pinto; Oliveira, Maria Margarida

    2007-01-01

    In spite of being among the main foods responsible for allergic reactions worldwide, soybean (Glycine max)-derived products continue to be increasingly widespread in a variety of food products due to their well-documented health benefits. Soybean also continues to be one of the elected target crops for genetic modification. The aim of this study was to characterize the soya proteome and, specifically, IgE-reactive proteins as well as to compare the IgE response in soya-allergic individuals to genetically modified Roundup Ready soya versus its non-transgenic control. We performed two-dimensional gel electrophoresis of protein extracts from a 5% genetically modified Roundup Ready flour sample and its non-transgenic control followed by Western blotting with plasma from 5 soya-sensitive individuals. We used peptide tandem mass spectrometry to identify soya proteins (55 protein matches), specifically IgE-binding ones, and to evaluate differences between transgenic and non-transgenic samples. We identified 2 new potential soybean allergens--one is maturation associated and seems to be part of the late embryogenesis abundant proteins group and the other is a cysteine proteinase inhibitor. None of the individuals tested reacted differentially to the transgenic versus non-transgenic samples under study. Soybean endogenous allergen expression does not seem to be altered after genetic modification. Proteomics should be considered a powerful tool for functional characterization of plants and for food safety assessment. Copyright (c) 2007 S. Karger AG, Basel.

  20. Is caesarean delivery associated with sensitization to food allergens and IgE-mediated food allergy: a systematic review.

    Science.gov (United States)

    Koplin, Jennifer; Allen, Katie; Gurrin, Lyle; Osborne, Nicholas; Tang, Mimi L K; Dharmage, Shyamali

    2008-12-01

    Several studies have shown differences in the composition of the gastrointestinal flora of children who develop sensitization to food allergens compared with non-allergic children. It has been hypothesized that changes in the gut microbiota resulting from caesarean section delivery could increase a child's risk of developing food allergy; however, studies examining the relationship between mode of delivery and food allergy have produced conflicting results. The objective of this review was to determine whether there is sufficient evidence to support an association between delivery by caesarean section and the development of sensitization to food allergens and immunoglobulin E (IgE) mediated food allergy. Using predefined inclusion and exclusion criteria, MEDLINE and PubMed were searched for studies investigating the relationship between caesarean section delivery and food allergy. The information on the quality of the studies and results were extracted and analysed systematically. The search identified four relevant studies as per our protocol. Symptomatic food allergy was used as the outcome in two studies and was found to occur more frequently in children born by caesarean section in one study while the second study found no association between food allergy diagnoses and mode of delivery. The other two studies measured levels of food antigen-specific IgE, with both studies showing an increase in sensitization to food allergens among children born by caesarean section. Overall, there is evidence that the risk of developing IgE-mediated sensitization to food allergens is increased among children delivered by caesarean section, however further studies using objectively diagnosed food allergy as the outcome are needed to verify whether this equates to an increase in confirmed food allergy. Future birth cohort studies should control for the effects of mode of delivery when investigating environmental modifiers of food allergy.

  1. [Hidden allergens in processed food : An update from the consumer's point of view].

    Science.gov (United States)

    Schnadt, Sabine; Pfaff, Sylvia

    2016-07-01

    Despite improved allergen labelling and careful avoidance strategies, hidden allergens in food remain a substantial risk for unintended reactions for consumers with food allergies. New data from a survey of the German Allergy and Asthma Association (Deutscher Allergie- und Asthmabund - DAAB) shows a slight decrease in the number of consumers that report allergic reactions to prepacked food. Still, 75 % (compared to 85 % in 2008) have experienced at least one allergic reaction after eating a prepacked food. In more than half of the cases, the reaction was classified as severe (with airway and/or cardiovascular symptoms such as respiratory distress, loss of blood pressure or anaphylactic shock). Again, more than 40 % (2008: 47 %, 2015: 42 %) reported that no information on the presence of the food allergens had been present on the label either as ingredients or as precautionary allergen labelling (PAL). Different possibilities are discussed under which food allergens may not be recognized or recognizable by consumers with food allergies, such as allergen labelling that is not easy to understand, unexpected occurrence of allergens as well as recipe changes in known foods. Examples are given as well as proposals for the improvement of the situation in order to better meet the goals of food information regulations to enable consumers with food allergies to make "informed choices which are safe for them" (Quote Regulation (EU) 1169/2011 - Reason 24).

  2. Group 5 allergens of timothy grass (Phl p 5) bear cross-reacting T cell epitopes with group 1 allergens of rye grass (Lol p 1).

    Science.gov (United States)

    Müller, W D; Karamfilov, T; Bufe, A; Fahlbush, B; Wolf, I; Jäger, L

    1996-04-01

    Selected human T cell clones reactive with group 5 allergens of timothy grass (Phl p 5) were cross-stimulated in specific proliferation assays with group 1 allergens of rye grass (Lol p 1). Such interspecies cross-reactivities result obviously from structural motifs presented on defined Phl p 5 fragments as shown with recombinant Phl p 5 products.

  3. Transfer of Chemically Modified Graphene with Retention of Functionality for Surface Engineering.

    Science.gov (United States)

    Whitener, Keith E; Lee, Woo-Kyung; Bassim, Nabil D; Stroud, Rhonda M; Robinson, Jeremy T; Sheehan, Paul E

    2016-02-10

    Single-layer graphene chemically reduced by the Birch process delaminates from a Si/SiOx substrate when exposed to an ethanol/water mixture, enabling transfer of chemically functionalized graphene to arbitrary substrates such as metals, dielectrics, and polymers. Unlike in previous reports, the graphene retains hydrogen, methyl, and aryl functional groups during the transfer process. This enables one to functionalize the receiving substrate with the properties of the chemically modified graphene (CMG). For instance, magnetic force microscopy shows that the previously reported magnetic properties of partially hydrogenated graphene remain after transfer. We also transfer hydrogenated graphene from its copper growth substrate to a Si/SiOx wafer and thermally dehydrogenate it to demonstrate a polymer- and etchant-free graphene transfer for potential use in transmission electron microscopy. Finally, we show that the Birch reduction facilitates delamination of CMG by weakening van der Waals forces between graphene and its substrate.

  4. Artemisia vulgaris pollen allergoids digestibility in the simulated conditions of the gastrointestinal tract

    OpenAIRE

    RATKO M. JANKOV; NATALIJA DJ. POLOVIC; MARIJA DJ. GAVROVIC-JANKULOVIC; LIDIJA BURAZER; DANICA DJERGOVIC-PETROVIC; OLGA VUCKOVIC; OLIKA DROBNJAK; ZORICA SPORCIC; MARINA ATANASKOVIC-MARKOVIC; RATKO M. JANKOV

    2006-01-01

    Chemically modified allergens (allergoids) have found use in both traditional and novel forms of immunotherapy of allergic disorders. Novel forms of immunotherapy include local allergen delivery, via the gastrointestinal tract. This study conveys the gastrointestinal stability of three types ofmugwort pollen allergoids under simulated conditions of the gut. Allergoids of the pollen extract of Artemisia vulgaris were obtained by means of potassium cyanate, succinic and maleic anhydride. Gastro...

  5. Isolation of allergenically active glycoprotein from Prosopis juliflora pollen.

    Science.gov (United States)

    Thakur, I S

    1989-03-01

    An allergenically active glycoprotein was homogeneously isolated from the aqueous extract of Prosopis juliflora pollen by ConA-Sepharose affinity chromatography. The molecular weight of this glycoprotein was 20,000 dalton, determined by gel filtration and SDS-PAGE. This fraction showed a total carbohydrate concentration of 25%. The purified glycoprotein revealed immunochemically most antigenic or allergenic and demonstrated homogeneous after reaction with P. juliflora pollen antiserum, characterized by gel diffusion, Immunoelectrophoresis and Radioallergosorbent test.

  6. Clinical efficacy of sublingual and subcutaneous birch pollen allergen-specific immunotherapy

    DEFF Research Database (Denmark)

    Khinchi, M S; Poulsen, Lars K.; Carat, F

    2004-01-01

    Both sublingual allergen-specific immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT) have a documented clinical efficacy, but only few comparative studies have been performed.......Both sublingual allergen-specific immunotherapy (SLIT) and subcutaneous immunotherapy (SCIT) have a documented clinical efficacy, but only few comparative studies have been performed....

  7. Evaluation of Molecular Basis of Cross Reactivity between Rye and Bermuda Grass Pollen Allergens

    Directory of Open Access Journals (Sweden)

    Ruby Tiwari

    2009-01-01

    Conclusions: Our data suggests that a possible explanation for the limited cross reactivity between the Pooids and Chloridoids may, in part, be due to the absence of group 5 allergen from Chloridoid grasses. This approach of using purified proteins may be applied to better characterize the cross allergenicity patterns between different grass pollen allergens.

  8. Influence of enzymatic hydrolysis on the allergenic reactivity of processed cashew and pistachio.

    Science.gov (United States)

    Cuadrado, Carmen; Cheng, Hsiaopo; Sanchiz, Africa; Ballesteros, Isabel; Easson, Michael; Grimm, Casey C; Dieguez, M Carmen; Linacero, Rosario; Burbano, Carmen; Maleki, Soheila J

    2018-02-15

    Cashew and pistachio allergies are considered a serious health problem. Previous studies have shown that thermal processing, pressurization and enzymatic hydrolysis may reduce the allergenic properties of food by changing the protein structure. This study assesses the allergenic properties of cashew and pistachio after thermal treatment (boiling and autoclaving), with or without pressure (autoclaving), and multiple enzymatic treatments under sonication, by SDS-PAGE, western blot and ELISA, with serum IgE of allergic individuals, and mass spectroscopy. Autoclaving and enzymatic hydrolysis under sonication separately induced a measurable reduction in the IgE binding properties of pastes made from treated cashew and pistachio nuts. These treatments were more effective with pistachio allergens. However, heat combined with enzymatic digestion was necessary to markedly lower IgE binding to cashew allergens. The findings identify highly effective simultaneous processing conditions to reduce or even abolish the allergenic potency of cashew and pistachio. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. AllerTool: a web server for predicting allergenicity and allergic cross-reactivity in proteins.

    Science.gov (United States)

    Zhang, Zong Hong; Koh, Judice L Y; Zhang, Guang Lan; Choo, Khar Heng; Tammi, Martti T; Tong, Joo Chuan

    2007-02-15

    Assessment of potential allergenicity and patterns of cross-reactivity is necessary whenever novel proteins are introduced into human food chain. Current bioinformatic methods in allergology focus mainly on the prediction of allergenic proteins, with no information on cross-reactivity patterns among known allergens. In this study, we present AllerTool, a web server with essential tools for the assessment of predicted as well as published cross-reactivity patterns of allergens. The analysis tools include graphical representation of allergen cross-reactivity information; a local sequence comparison tool that displays information of known cross-reactive allergens; a sequence similarity search tool for assessment of cross-reactivity in accordance to FAO/WHO Codex alimentarius guidelines; and a method based on support vector machine (SVM). A 10-fold cross-validation results showed that the area under the receiver operating curve (A(ROC)) of SVM models is 0.90 with 86.00% sensitivity (SE) at specificity (SP) of 86.00%. AllerTool is freely available at http://research.i2r.a-star.edu.sg/AllerTool/.

  10. Allergen manufacturing and quality aspects for allergen immunotherapy in Europe and the United States: An analysis from the EAACI AIT Guidelines Project.

    Science.gov (United States)

    Bonertz, A; Roberts, G; Slater, J E; Bridgewater, J; Rabin, R L; Hoefnagel, M; Timon, M; Pini, C; Pfaar, O; Sheikh, A; Ryan, D; Akdis, C; Goldstein, J; Poulsen, L K; van Ree, R; Rhyner, C; Barber, D; Palomares, O; Pawankar, R; Hamerlijnk, D; Klimek, L; Agache, I; Angier, E; Casale, T; Fernandez-Rivas, M; Halken, S; Jutel, M; Lau, S; Pajno, G; Sturm, G; Varga, E M; Gerth van Wijk, R; Bonini, S; Muraro, A; Vieths, S

    2018-04-01

    Adequate quality is essential for any medicinal product to be eligible for marketing. Quality includes verification of the identity, content and purity of a medicinal product in combination with a specified production process and its control. Allergen products derived from natural sources require particular considerations to ensure adequate quality. Here, we describe key aspects of the documentation on manufacturing and quality aspects for allergen immunotherapy products in the European Union and the United States. In some key parts, requirements in these areas are harmonized while other fields are regulated separately between both regions. Essential differences are found in the use of Reference Preparations, or the requirement to apply standardized assays for potency determination. As the types of products available are different in specific regions, regulatory guidance for such products may also be available in one specific region only, such as for allergoids in the European Union. Region-specific issues and priorities are a result of this. As allergen products derived from natural sources are inherently variable in their qualitative and quantitative composition, these products present special challenges to balance the variability and ensuring batch-to-batch consistency. Advancements in scientific knowledge on specific allergens and their role in allergic disease will consequentially find representation in future regulatory guidelines. © 2017 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

  11. EAACI Guidelines on allergen immunotherapy

    DEFF Research Database (Denmark)

    Pajno, G B; Fernandez-Rivas, M; Arasi, S

    2018-01-01

    . This Guideline, prepared by the European Academy of Allergy and Clinical Immunology (EAACI) Task Force on Allergen Immunotherapy for IgE-mediated Food Allergy, aims to provide evidence-based recommendations for active treatment of IgE-mediated food allergy with FA-AIT. Immunotherapy relies on the delivery...

  12. Mechanism for initiation of food allergy: Dependence on skin barrier mutations and environmental allergen costimulation.

    Science.gov (United States)

    Walker, Matthew T; Green, Jeremy E; Ferrie, Ryan P; Queener, Ashley M; Kaplan, Mark H; Cook-Mills, Joan M

    2018-02-15

    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.

  13. Comparative and Evolutionary Analysis of Grass Pollen Allergens Using Brachypodium distachyon as a Model System.

    Directory of Open Access Journals (Sweden)

    Akanksha Sharma

    Full Text Available 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

  14. Covering chemical diversity of genetically-modified tomatoes using metabolomics for objective substantial equivalence assessment.

    Directory of Open Access Journals (Sweden)

    Miyako Kusano

    Full Text Available As metabolomics can provide a biochemical snapshot of an organism's phenotype it is a promising approach for charting the unintended effects of genetic modification. A critical obstacle for this application is the inherently limited metabolomic coverage of any single analytical platform. We propose using multiple analytical platforms for the direct acquisition of an interpretable data set of estimable chemical diversity. As an example, we report an application of our multi-platform approach that assesses the substantial equivalence of tomatoes over-expressing the taste-modifying protein miraculin. In combination, the chosen platforms detected compounds that represent 86% of the estimated chemical diversity of the metabolites listed in the LycoCyc database. Following a proof-of-safety approach, we show that % had an acceptable range of variation while simultaneously indicating a reproducible transformation-related metabolic signature. We conclude that multi-platform metabolomics is an approach that is both sensitive and robust and that it constitutes a good starting point for characterizing genetically modified organisms.

  15. Covering Chemical Diversity of Genetically-Modified Tomatoes Using Metabolomics for Objective Substantial Equivalence Assessment

    Science.gov (United States)

    Hirai, Tadayoshi; Oikawa, Akira; Matsuda, Fumio; Fukushima, Atsushi; Arita, Masanori; Watanabe, Shin; Yano, Megumu; Hiwasa-Tanase, Kyoko; Ezura, Hiroshi; Saito, Kazuki

    2011-01-01

    As metabolomics can provide a biochemical snapshot of an organism's phenotype it is a promising approach for charting the unintended effects of genetic modification. A critical obstacle for this application is the inherently limited metabolomic coverage of any single analytical platform. We propose using multiple analytical platforms for the direct acquisition of an interpretable data set of estimable chemical diversity. As an example, we report an application of our multi-platform approach that assesses the substantial equivalence of tomatoes over-expressing the taste-modifying protein miraculin. In combination, the chosen platforms detected compounds that represent 86% of the estimated chemical diversity of the metabolites listed in the LycoCyc database. Following a proof-of-safety approach, we show that % had an acceptable range of variation while simultaneously indicating a reproducible transformation-related metabolic signature. We conclude that multi-platform metabolomics is an approach that is both sensitive and robust and that it constitutes a good starting point for characterizing genetically modified organisms. PMID:21359231

  16. DNA aptamers against the Lup an 1 food allergen.

    Directory of Open Access Journals (Sweden)

    Pedro Nadal

    Full Text Available Using in vitro selection, high affinity DNA aptamers to the food allergen Lup an 1, ß-conglutin, were selected from a pool of DNA, 93 bases in length, containing a randomised sequence of 49 bases. ß-conglutin was purified from lupin flour and chemically crosslinked to carboxylated magnetic beads. Peptide mass fingerprinting was used to confirm the presence of the ß-conglutin. Single stranded DNA was generated from the randomised pool using T7 Gene 6 Exonuclease and was subsequently incubated with the magnetic beads and the captured DNA was released and amplified prior to a further round of Systematic Evolution of Ligands by Exponential Enrichment (SELEX. Evolution was monitored using enzyme linked oligonucleotide assay and surface plasmon resonance. Once a plateau in evolution was reached, the isolated DNA sequences were cloned and sequenced. The consensus motif was identified via alignment of the sequences and the affinities of these sequences for immobilised ß-conglutin were determined using surface plasmon resonance. The selected aptamer was demonstrated to be highly specific, showing no cross-reactivity with other flour ingredients or with other conglutin fractions of lupin. The secondary structures of the selected aptamers were predicted using m-fold. Finally, the functionality of the selected aptamers was demonstrated using a competitive assay for the quantitative detection of ß-conglutin. . Future work will focus on structure elucidation and truncation of the selected sequences to generate a smaller aptamer for application to the analysis of the Lup an 1 allergen in foodstuffs.

  17. Airway responses towards allergens - from the airway epithelium to T cells

    DEFF Research Database (Denmark)

    Papazian, Dick; Hansen, Søren; Würtzen, Peter A

    2015-01-01

    -damaged, healthy epithelium lowers the DCs ability to induce inflammatory T cell responses towards allergens. The purpose of this review is to summarize the current knowledge on which signals from the airway epithelium, from first contact with inhaled allergens all the way to the ensuing Th2 cell responses...

  18. Establishment of Reference Doses for residues of allergenic foods: Report of the VITAL Expert Panel

    NARCIS (Netherlands)

    Taylor, S.L.; Baumert, J.L.; Kruizinga, A.G.; Remington, B.C.; Crevel, R.W.R.; Brooke-Taylor, S.; Allen, K.J.; Houben, G.

    2014-01-01

    In 2011, an expert panel was assembled to establish appropriate Reference Doses for allergenic food residues as a part of the VITAL (Voluntary Incidental Trace Allergen Labeling) program of The Allergen Bureau of Australia & New Zealand (ABA). These Reference Doses would guide advisory labeling

  19. Percutaneous penetration characteristics and release kinetics of contact allergens encapsulated in ethosomes

    DEFF Research Database (Denmark)

    Madsen, Jakob Torp; Vogel, Stefan; Johansen, Jeanne Duus

    2011-01-01

    Formulation of the contact allergens dinitrochlorobenzene and isoeugenol in ethanolic liposomes (ethosomes) increases their sensitizing properties in the local lymph node assay compared with an ethanol-water formulation of the allergens. Likewise, isoeugenol and methyldibromo-glutaronitrile formu...

  20. In vitro methods for hazard assessment of industrial chemicals – opportunities and challenges

    Directory of Open Access Journals (Sweden)

    Chin Lin eWong

    2015-05-01

    Full Text Available Allergic contact dermatitis (ACD is a delayed-type hypersensitivity immune reaction mediated by T-lymphocytes as a result of repeated exposure of an allergen primarily on skin. ACD accounts for up to 95% of occupational skin diseases (OSDs, with epoxy resins implicated as one of the most common causes of ACD. Efficient high-throughput in vitro screening for accurate identification of compounds and materials that may pose hazardous risks in the workplace is crucial. At present, the murine local lymph node assay (LLNA is the ‘method of choice’ for predicting the sensitizing potency of contact allergens. As the 3Rs principles of reduction, refinement and replacement in animal testing has gained political and economic momentum, several in vitro screening methods have been developed for identifying potential contact allergens. To date, these latter methods have been utilized primarily to assess the skin sensitizing potential of the chemical components of cosmetic products with scant research attention as to the applicability of these methods to industrial chemicals, particularly epoxy resins. Herein we review the currently utilized in vitro methods and identify the knowledge gaps with regard to assessing the generalizability of in vitro screening methods for assessing the skin sensitizing potential of industrial chemicals.

  1. Recombinant allergen-based IgE testing to distinguish bee and wasp allergy.

    Science.gov (United States)

    Mittermann, Irene; Zidarn, Mihaela; Silar, Mira; Markovic-Housley, Zora; Aberer, Werner; Korosec, Peter; Kosnik, Mitja; Valenta, Rudolf

    2010-06-01

    The identification of the disease-causing insect in venom allergy is often difficult. To establish recombinant allergen-based IgE tests to diagnose bee and yellow jacket wasp allergy. Sera from patients with bee and/or wasp allergy (n = 43) and patients with pollen allergy with false-positive IgE serology to venom extracts were tested for IgE reactivity in allergen extract-based tests or with purified allergens, including nonglycosylated Escherichia coli-expressed recombinant (r) Api m 1, rApi m 2, rVes v 5, and insect cell-expressed, glycosylated rApi m 2 as well as 2 natural plant glycoproteins (Phl p 4, bromelain). The patients with venom allergy could be diagnosed with a combination of E coli-expressed rApi m 1, rApi m 2, and rVes v 5 whereas patients with pollen allergy remained negative. For a group of 29 patients for whom the sensitizing venom could not be identified with natural allergen extracts, testing with nonglycosylated allergens allowed identification of the sensitizing venom. Recombinant nonglycosylated allergens also allowed definition of the sensitizing venom for those 14 patients who had reacted either with bee or wasp venom extracts. By IgE inhibition studies, it is shown that glycosylated Api m 2 contains carbohydrate epitopes that cross-react with natural Api m 1, Ves v 2, natural Phl p 4, and bromelain, thus identifying cross-reactive structures responsible for serologic false-positive test results or double-positivity to bee and wasp extracts. Nonglycosylated recombinant bee and wasp venom allergens allow the identification of patients with bee and wasp allergy and should facilitate accurate prescription of venom immunotherapy. Copyright (c) 2010 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  2. Development and evolution of risk assessment for food allergens

    DEFF Research Database (Denmark)

    Crevel, Rene' W. R.; Baumert, Joseph L.; Baka, Athanasia

    2014-01-01

    The need to assess the risk from food allergens derives directly from the need to manage effectively this food safety hazard. Work spanning the last two decades dispelled the initial thinking that food allergens were so unique that the risk they posed was not amenable to established risk assessme...... provided valuable insights, leading to further refinements and generating testable hypotheses. Their application to estimate the risk posed by the concurrent consumption of two potentially contaminated foods illustrates their power....

  3. Pollen lipidomics: lipid profiling exposes a notable diversity in 22 allergenic pollen and potential biomarkers of the allergic immune response.

    Directory of Open Access Journals (Sweden)

    Mohamed Elfatih H Bashir

    Full Text Available BACKGROUND/AIM: Pollen grains are the male gametophytes that deliver sperm cells to female gametophytes during sexual reproduction of higher plants. Pollen is a major source of aeroallergens and environmental antigens. The pollen coat harbors a plethora of lipids that are required for pollen hydration, germination, and penetration of the stigma by pollen tubes. In addition to proteins, pollen displays a wide array of lipids that interact with the human immune system. Prior searches for pollen allergens have focused on the identification of intracellular allergenic proteins, but have largely overlooked much of the extracellular pollen matrix, a region where the majority of lipid molecules reside. Lipid antigens have attracted attention for their potent immunoregulatory effects. By being in close proximity to allergenic proteins on the pollen surface when they interact with host cells, lipids could modify the antigenic properties of proteins. METHODOLOGY/PRINCIPAL FINDINGS: We performed a comparative pollen lipid profiling of 22 commonly allergenic plant species by the use of gas chromatography-mass spectroscopy, followed by detailed data mining and statistical analysis. Three experiments compared pollen lipid profiles. We built a database library of the pollen lipids by matching acquired pollen-lipid mass spectra and retention times with the NIST/EPA/NIH mass-spectral library. We detected, identified, and relatively quantified more than 106 lipid molecular species including fatty acids, n-alkanes, fatty alcohols, and sterols. Pollen-derived lipids stimulation up-regulate cytokines expression of dendritic and natural killer T cells co-culture. CONCLUSIONS/SIGNIFICANCE: Here we report on a lipidomic analysis of pollen lipids that can serve as a database for identifying potential lipid antigens and/or novel candidate molecules involved in allergy. The database provides a resource that facilitates studies on the role of lipids in the

  4. Augmentation of skin response by exposure to a combination of allergens and irritants - a review

    DEFF Research Database (Denmark)

    Pedersen, Line Kynemund; Johansen, Jeanne Duus; Held, Elisabeth

    2004-01-01

    Clinical experimental studies on contact dermatitis (CD) often evaluate the effect of one allergen or one irritant at a time. In real life, the skin is often exposed to more allergens, more irritants or allergens and irritants in combination. This combined exposure may potentially influence irrit...

  5. Vinegar decreases allergenic response in lentil and egg food allergy.

    Science.gov (United States)

    Armentia, A; Dueñas-Laita, A; Pineda, F; Herrero, M; Martín, B

    2010-01-01

    Food allergy results from an atypical response of the mucosal immune system to orally consumed allergens. Antacid medication inhibits the digestion of dietary proteins and causes food allergy. A decrease of the gastric pH might enhance the function of digestion and reduce the risk of food allergy. To test a possible decrease in the allergenicity of powerful food allergens (egg, chicken, lentils) with the addition of vinegar during the cooking process. We included seven patients who suffered from anaphylaxis due to egg, chicken and lentils. We added vinegar to egg, chicken and lentil processed extracts used for skin prick tests (SPT) and compared the wheal areas obtained with the same extracts sources and the same way but without vinegar addition. Immunodetection was performed with the different processed extracts and patients' sera. Only one patient consented food challenge with vinegar-marinated-chicken. Wheal areas were significantly minor with the food extract with vinegar. Immunodetection showed a decrease of the response with vinegar processed extracts. Vinegar addition during the cooking process may decrease lentil and chicken allergenicity. Copyright 2009 SEICAP. Published by Elsevier Espana. All rights reserved.

  6. Clinical importance of non-specific lipid transfer proteins as food allergens

    NARCIS (Netherlands)

    van Ree, R.

    2002-01-01

    Non-specific lipid transfer proteins (nsLTPs) have recently been identified as plant food allergens. They are good examples of true food allergens, in the sense that they are capable of sensitizing, i.e. inducing specific IgE, as well as of eliciting severe symptoms. This is in contrast with most

  7. Peanut allergen Ara h 3: Isolation from peanuts and biochemical characterization

    NARCIS (Netherlands)

    Koppelman, S.J.; Knol, E.F.; Vlooswijk, R.A.A.; Wensing, M.; Knulst, A.C.; Hefle, S.L.; Gruppen, H.; Piersma, S.

    2003-01-01

    Background: Peanut allergen Ara h 3 has been the subject of investigation for the last few years. The reported data strongly depend on recombinant Ara h 3, since a purification protocol for Ara h 3 from peanuts was not available. Methods: Peanut allergen Ara h 3 (glycinin), was purified and its

  8. Watermelon and ragweed share allergens.

    Science.gov (United States)

    Enberg, R N; Leickly, F E; McCullough, J; Bailey, J; Ownby, D R

    1987-06-01

    A biotin-avidin amplified ELISA was used to measure antigen-specific IgE for ragweed, representative members of the gourd family (watermelon, cantaloupe, honeydew melon, zucchini, and cucumber), and banana in the sera of 192 allergic patients, each with an IgE greater than or equal to 180 microns/ml. Sixty-three percent (120/192) of the sera contained antiragweed IgE, and of these patients, 28% to 50% contained IgE specific for any single gourd family member. In contrast, no greater than 11% of the sera positive for a given gourd or banana were negative for ragweed. Correlations between ragweed and gourd-specific IgE levels were significant (p less than 0.001), and correlation coefficients between any two gourds exceeded 0.79. In an ELISA system, the extracts of watermelon and ragweed inhibited each other in a dose-dependent manner; the resulting nonparallel inhibition curves indicate that some, but not all, of the allergens in the two extracts are cross-reactive. Isoelectric focusing of watermelon and ragweed extracts in narrow range gel (pH 4 to 6) followed by immunoblotting demonstrated six watermelon allergen bands with isoelectric points identical to those of ragweed allergens. Several remaining bands in the two extracts had differing isoelectric points, however. Six of 26 patients interviewed with watermelon-specific IgE reported developing oropharyngeal symptoms (itching and/or swelling of the lips, tongue, or throat) after ingesting at least one of the study foods, whereas only one of 25 patients interviewed without detectable watermelon-specific IgE reported similar symptoms (p = 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

  9. Influence of food processing on the immunochemical stability of celery allergens

    International Nuclear Information System (INIS)

    Jankiewicz, A.; Baltes, W.; Bögl, K.W.; Dehne, L.I.; Jamin, A.; Hoffmann, A.; Haustein, D.; Vieths, S.

    1997-01-01

    Celery roots were processed by microwave heating, cooking, drying, γ-irradiation, ultra high pressure treatment and high voltage impulse treatment. The immunochemical stabilities of the three known allergenic structures of celery were tested with sera from patients who were sensitised to celery. In addition, rabbit antisera were used to detect the allergens profilin and Api g I on celery immunoblots. The specificity and reactivity of IgE from the patients' sera were investigated by immunoblotting, by an enzyme allergosorbent test (EAST) and by dose-related IgE inhibition experiments. The results of all three methods agreed closely and indicated high antigenic and allergenic activity in native celery which was reduced by thermal processing. The heat-stability of the known celery allergens decreased in the following order: carbohydrate epitopes > profilin > Api g 1. In contrast, the allergenicity was only mildly reduced by non-thermal processing. The results obtained with human IgE were confirmed by an in vitro mediator-release assay that is based on rat basophil leukemia cells (RBL cells) which were passively sensitised with celery-specific murine IgE. With sera from mice that had been immunised with native celery, the native sample and non-thermal celery preparations elicited the strongest mediator release, whereas a weak response was obtained with samples from heat-processed celery. These results agreed closely with the data obtained in allergic patients whose IgE antibodie

  10. Simultaneous determination of four food allergens using compact disc immunoassaying technology.

    Science.gov (United States)

    Badran, Ahmed Ali; Morais, Sergi; Maquieira, Ángel

    2017-03-01

    A multiplex competitive microimmunoassay for the simultaneous determination of gliadin, casein, β-lactoglobulin, and ovalbumin is presented. The assay in microarray format is performed on a DVD where the allergens are physisorbed on the polycarbonate surface of the disc. The immunointeraction is detected using a mixture of specific gold-labeled antibodies and the signal amplified with the silver enhancement method. The optical density of the precipitate, read by a DVD drive, is related to the concentration of the four allergens in sample. An optimized protocol for the simultaneous extraction of the allergen proteins from food samples is also addressed. The suitability of the method is demonstrated for the simultaneous quantitative extraction and determination of the targeted allergens in spiked baby foods, juices, and beers. The sensitivity (EC50) of the multiplexed assay was 0.04, 0.40, 0.08, and 0.16 mg L -1 for gliadin, casein, β-lactoglobulin, and ovalbumin, respectively, and the recovery results from the analysis of food samples ranged from 72 to 117%. A portable, easy-to-use, array-based bioanalytical method is developed for quantification of food allergens with a limit of detection below the accepted levels of the international legislations, which allows promotion of food safety and quality. Graphical abstract GLI Gliadin, CAS Casein, β-LAC β-lactoglobulin, OVA Ovalbumin.

  11. Identification of the major allergens of Indian scad (Decapterus russelli).

    Science.gov (United States)

    Misnan, Rosmilah; Murad, Shahnaz; Jones, Meinir; Taylor, Graham; Rahman, Dinah; Arip, Masita; Abdullah, Noormalin; Mohamed, Jamaluddin

    2008-12-01

    The purpose of this study was to characterize major allergens of Indian scad (Decapterus russelli) which is among the most commonly consumed fish in Malaysia. Raw and cooked extracts of the fish were prepared. Protein profiles and IgE binding patterns were produced by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting using sera from subjects with fish allergy. The major allergens of the fish were then identified by two-dimensional electrophoresis (2-DE), followed by mass spectrometry of the peptide digests. The SDS-PAGE of the raw extract revealed 27 protein fractions over a wide molecular weight range, while the cooked extract demonstrated only six protein fractions. The 1-DE immunoblotting detected 14 IgE-binding proteins, with a molecular weight range from 90 to fish. The approximately 12 kDa band was a heat-resistant protein while the approximately 51 and 46 kDa proteins were sensitive to heat. The 2-DE gel profile of the raw extract demonstrated > 100 distinct protein spots and immunoblotting detected at least 10 different major IgE reactive spots with molecular masses as expected and isoelectric point (pI) values ranging from 4.0 to 7.0. A comparison of the major allergenic spot sequences of the 12 kDa proteins with known protein sequences in databases revealed extensive similarity with fish parvalbumin. In conclusion, this study demonstrated that a parvalbumin which is similar to Gad c 1 is the major allergen of Indian scad. Interestingly, we also detected heat-sensitive proteins as major allergenic components in our fish allergy patients.

  12. T cell reactivity with allergoids: influence of the type of APC.

    Science.gov (United States)

    Kahlert, H; Grage-Griebenow, E; Stüwe, H T; Cromwell, O; Fiebig, H

    2000-08-15

    The use of allergoids for allergen-specific immunotherapy has been established for many years. The characteristic features of these chemically modified allergens are their strongly reduced IgE binding activity compared with the native form and the retained immunogenicity. T cell reactivity of chemically modified allergens is documented in animals, but in humans indirect evidence of reactivity has been concluded from the induction of allergen-specific IgG during immunotherapy. Direct evidence of T cell reactivity was obtained recently using isolated human T cells. To obtain further insight into the mechanism of action of allergoids, we compared the Ag-presenting capacity of different APC types, including DC and macrophages, generated from CD14+ precursor cells from the blood of grass pollen allergic subjects, autologous PBMC, and B cells. These APC were used in experiments together with Phl p 5-specific T cell clones under stimulation with grass pollen allergen extract, rPhl p 5b, and the respective allergoids. Using DC and macrophages, allergoids exhibited a pronounced and reproducible T cell-stimulating capacity. Responses were superior to those with PBMC, and isolated B cells failed to present allergoids. Considerable IL-12 production was observed only when using the DC for Ag presentation of both allergens and allergoids. The amount of IL-10 in supernatants was dependent on the phenotype of the respective T cell clone. High IL-10 production was associated with suppressed IL-12 production from the DC in most cases. In conclusion, the reactivity of Th cells with allergoids is dependent on the type of the APC.

  13. Highlight on Bottlenecks in Food Allergen Analysis: Detection and Quantification by Mass Spectrometry.

    Science.gov (United States)

    Planque, Mélanie; Arnould, Thierry; Renard, Patricia; Delahaut, Philippe; Dieu, Marc; Gillard, Nathlie

    2017-07-01

    Food laboratories have developed methods for testing allergens in foods. The efficiency of qualitative and quantitative methods is of prime importance in protecting allergic populations. Unfortunately, food laboratories encounter barriers to developing efficient methods. Bottlenecks include the lack of regulatory thresholds, delays in the emergence of reference materials and guidelines, and the need to detect processed allergens. In this study, ultra-HPLC coupled to tandem MS was used to illustrate difficulties encountered in determining method performances. We measured the major influences of both processing and matrix effects on the detection of egg, milk, soy, and peanut allergens in foodstuffs. The main goals of this work were to identify difficulties that food laboratories still encounter in detecting and quantifying allergens and to sensitize researchers to them.

  14. Food allergens inducing a lymphocyte-mediated immunological reaction in canine atopic-like dermatitis.

    Science.gov (United States)

    Suto, Akemi; Suto, Yukinori; Onohara, Nozomi; Tomizawa, Yu; Yamamoto-Sugawara, Yukiko; Okayama, Taro; Masuda, Kenichi

    2015-02-01

    Canine atopic-like dermatitis (ALD) is suspected to be associated with food allergies, particularly those mediated by lymphocytes. In this study, 54 cases were included as ALD dogs, based on the negative IgE test results. In the dogs, the percentage of activated cells in helper-T lymphocytes was measured by flow cytometry using cultured peripheral lymphocytes under food allergen stimulation. We observed that 49 of the 54 ALD dogs (90.7%) had positive lymphocyte reactions against one or more food allergens. The most common food allergen was soybean, showing positive results in 21 dogs (42.9%), while the allergen to cause the lowest number of reactions was catfish (only 5 dogs, 10.2%). These results may be useful in considering elimination diets for ALD dogs.

  15. 27 CFR 5.32a - Voluntary disclosure of major food allergens.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Voluntary disclosure of major food allergens. 5.32a Section 5.32a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... Labeling Requirements for Distilled Spirits § 5.32a Voluntary disclosure of major food allergens. (a...

  16. 27 CFR 7.22a - Voluntary disclosure of major food allergens.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Voluntary disclosure of major food allergens. 7.22a Section 7.22a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... Labeling Requirements for Malt Beverages § 7.22a Voluntary disclosure of major food allergens. (a...

  17. Catalytic conversion of biomass pyrolysis-derived compounds with chemical liquid deposition (CLD) modified ZSM-5.

    Science.gov (United States)

    Zhang, Huiyan; Luo, Mengmeng; Xiao, Rui; Shao, Shanshan; Jin, Baosheng; Xiao, Guomin; Zhao, Ming; Liang, Junyu

    2014-03-01

    Chemical liquid deposition (CLD) with KH550, TEOS and methyl silicone oil as the modifiers was used to modify ZSM-5 and deposit its external acid sites. The characteristics of modified catalysts were tested by catalytic conversion of biomass pyrolysis-derived compounds. The effects of different modifying conditions (deposited amount, temperature, and time) on the product yields and selectivities were investigated. The results show KH550 modified ZSM-5 (deposited amount of 4%, temperature of 20°C and time of 6h) produced the maximum yields of aromatics (24.5%) and olefins (16.5%), which are much higher than that obtained with original ZSM-5 catalyst (18.8% aromatics and 9.8% olefins). The coke yield decreased from 44.1% with original ZSM-5 to 26.7% with KH550 modified ZSM-5. The selectivities of low-molecule-weight hydrocarbons (ethylene and benzene) decreased, while that of higher molecule-weight hydrocarbons (propylene, butylene, toluene, and naphthalene) increased comparing with original ZSM-5. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. Molecular, Structural and Immunological Characterization of Der p 18, a Chitinase-Like House Dust Mite Allergen.

    Directory of Open Access Journals (Sweden)

    Yvonne Resch

    Full Text Available 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.

  19. Association between pet ownership and the sensitization to pet allergens in adults with various allergic diseases.

    Science.gov (United States)

    Park, Yong-Bum; Mo, Eun-Kyung; Lee, Jae-Young; Kim, Joo-Hee; Kim, Cheol-Hong; Hyun, In-Gyu; Choi, Jeong-Hee

    2013-09-01

    As pet ownership increases, sensitization to animal allergens due to domestic exposure is a concern. Sensitization to animal allergens may occur from indirect exposure, as well as direct ownership of animals. However, there have been conflicting results regarding the association between pet ownership and sensitization to animal allergens in adults. In total, 401 patients with various allergic diseases were enrolled in this study. We performed skin prick tests with 55 common inhalant and food allergens, including dog, cat, and rabbit allergens. A mean wheal diameter of 3 mm or greater was considered a positive reaction. The exposure modality to each animal allergen was investigated using a questionnaire and included present ownership, past ownership, occupational exposure, occasional exposure, contact with pet owner, and no contact. Present ownership, past ownership, occupational, and occasional exposure were regarded as direct exposure. The sensitization rate for animal allergens was 20.4% for dog, 15.0% for cat, and 9.0% for rabbit. Direct exposure to dogs (72.0%) was significantly higher than that of other animals (18.4% for cats and 16.7% for rabbits), whereas 'no contact' with cats (78.3%) and rabbits (83.3%) was significantly higher than with dogs (26.8%; Prisk factors for sensitization to animal allergens were sensitization to Dermatophagoides pteronyssinus (OR=2.4, P=0.052), Dermatophagoides farinae (OR=5.1, Prisk factor was sensitization to Alternaria (OR=6.0, P<0.002). These results suggest that direct exposure to dogs contributes to the sensitization to dog allergens in patients with allergic diseases, whereas indirect exposure to cats and rabbits may induce sensitization to each animal's allergen.

  20. Allergen source materials: state-of-the-art.

    Science.gov (United States)

    Esch, Robert E

    2009-01-01

    A variety of positive outcomes can be realized from validation and risk management activities (see Table 4). They are dependent on the participation of multiple functional groups including the quality unit, regulatory and legal affairs, engineering and production operations, research and development, and sales and marketing. Quality risk management is receiving increased attention in the area of public health, pharmacovigilance, and pharmaceutical manufacturing. Recent examples of its regulatory use in our industry include the assessment of the potential risks of transmissible spongiform encephalopathies (TSE) agents through contaminated products], the risks of precipitates in allergenic extracts, and the revision of the potency limits for standardized dust mite and grass allergen vaccines. Its application to allergen source material process validation activities allowed for a practical strategy, especially in a complex manufacturing environment involving hundreds of products with multiple intended uses. In addition, the use of tools such as FMEA was useful in evaluating proposed changes made to manufacturing procedures and product specifications, new regulatory actions, and customer feedback or complaints. The success of such a quality assurance programs will ultimately be reflected in the elimination or reduction of product failures, improvement in the detection and prediction of potential product failures, and increased confidence in product quality.

  1. Allergen-specific immunotherapy prescription patterns in veterinary practice: a US population-based cohort study.

    Science.gov (United States)

    Tater, Kathy Chu; Cole, William Elliott; Pion, Paul David

    2017-08-01

    Poor adherence to continuing allergen-specific immunotherapy treatment (ASIT) may be an issue in veterinary medicine. No studies describe how allergen tests are used in general veterinary practice, including the percentage of patients that receive ASIT after allergen testing. Assess veterinary ASIT patterns in United States general practices. Dogs (n = 2,557) and 121 cats allergen-tested at 177 hospitals (173 general practice and four specialty practices) in 44 states. Invoiced service descriptions of allergen tests and ASIT orders were retrieved from an aggregated database of veterinary practices. In general practice, 42% (992 of 2,360) of patients did not begin ASIT after allergen testing. ASIT was not refilled for 29% (398 of 1,368) of patients after the initial order. ASIT was initiated and refilled more often in dogs (56.6%, 71.4%, respectively) than cats (38%, 67.4%). Specialty practice patients had the highest ASIT initiation (94.4%) and refill (92.7%) percentages in comparison to general practices (P < 0.001). Size, age, geographical region and type of practice were associated with whether dogs were started on ASIT. Geographical region was also associated with refilling a prescription for ASIT, which was considered to be evidence of adherence to continuing treatment. Almost one third of clients failed to continue ASIT beyond the initial order, which is a much shorter duration of therapy than the 12 months recommended for determining ASIT efficacy. A large number of general practice patients did not begin ASIT after allergen testing, likely due to differences in how clinicians in general and dermatology practices use allergen tests. © 2017 ESVD and ACVD.

  2. EFFECTIVENESS OF SUBCUTANEOUS ALLERGEN-SPECIFIC IMMUNOTHERAPY WITH TREE POLLEN ALLERGEN EXTRACT ADSORBED ON CALCIUM PHOSPHATE IN CHILDREN WITH ALLERGIC RHINOCONJUNCTIVITIS: RESULTS OF A 2 YEAR-LONG OBSERVATION

    Directory of Open Access Journals (Sweden)

    N. V. Shakhova

    2014-01-01

    Full Text Available The study was aimed at evaluating effectiveness and safety of subcutaneous allergen-specific immunotherapy (scASIT with tree pollen allergen extract adsorbed on calcium phosphate at allergic rhinoconjunctivitis in children. Patients and methods: open-label prospective study of 50 children and adolescents (5-17 years of age with allergic rhinoconjunctivitis caused by high sensitivity to tree pollen allergens. The first group involved the patients undergoing scASIT for 2 years 6 months (n = 23, the control group – the patients (n = 27 not undergoing any specific immunotherapy. Results: scASIT was accompanied by a statistically significant (in comparison with the control group reduction in intensity of rhinoconjunctivitis symptoms (6.1 ± 3.1; 11.8 ± 4.5; p = 0.00002, reduction in the use of symptomatic drugs (1.0 ± 0.4; 1.8 ± 0.3; p = 0.000004 and improvement of quality of all spheres of children’s life – physical (p = 0.001, social (p = 0.04, emotional (p = 0.001 and role functioning (p = 0.03. Systemic side reactions were not observed in the patients. Local reactions were observed in 23% of all allergen injections. Conclusions: the authors established high effectiveness and safety of scASIT with tree pollen allergen extract adsorbed on calcium phosphate suspension at allergic rhinoconjunctivitis in children. 

  3. A procedure for grouping food consumption data for use in food allergen risk assessment

    DEFF Research Database (Denmark)

    Birot, Sophie; Madsen, Charlotte Bernhard; Kruizinga, Astrid G.

    2017-01-01

    Food allergic subjects need to avoid the allergenic food that triggers their allergy. However, foods can also contain unintended allergens. Food manufacturers or authorities need to perform a risk assessment to be able to decide if unintended allergen presence constitutes a risk to food allergic...... consumers. One of the input parameters in risk assessment is the amount of a given food consumed in a meal. There has been little emphasis on how food consumption data can be used in food allergen risk assessment. The aim of the study was to organize the complex datasets from National Food Consumption...... Surveys from different countries (France, Netherlands and Denmark) to be manageable in food allergen risk assessment. To do this, a two-step method was developed. First, based on initial groups of similar food items, the homogeneity of consumption was evaluated using a customized clustering method. Then...

  4. Citral a fragrance allergen and irritant.

    Science.gov (United States)

    Heydorn, S; Menné, T; Andersen, K E; Bruze, M; Svedman, C; White, I R; Basketter, D A

    2003-07-01

    Citral is a well known contact allergen and a contact irritant. Routine patch testing in the past may have been restricted because of possible irritant (IR) patch test responses. 586 consecutive patients, with hand eczema, were patch tested with a selection of fragrances including citral 2% petrolatum and the European standard series. 28 of the patients showed a positive patch test reaction (+ to +++) to citral and 82 at least 1 IR patch test reaction and no positive patch test reaction to citral. A statistically significant association between a positive patch test reaction to citral and positive patch test reactions to other fragrances compared with IR reactions (n = 82) was established. The difference regarding fragrance history found between those with IR and positive reactions to citral was not significant. Citral could be an allergen and/or irritant, worthy of further more extensive studies.

  5. 27 CFR 4.32a - Voluntary disclosure of major food allergens.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Voluntary disclosure of major food allergens. 4.32a Section 4.32a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX... Requirements for Wine § 4.32a Voluntary disclosure of major food allergens. (a) Definitions. For purposes of...

  6. [The contribution of food and airborne allergens in the pathogenesis of atopic dermatitis].

    Science.gov (United States)

    Dynowska, Dorota; Kolarzyk, Emilia; Schlegel-Zawadzka, Małgorzata; Dynowski, Wojciech

    2002-01-01

    Food hypersensitivity and airborne allergens may play a role in the pathogenesis of atopic dermatitis (AD). The aim of this study was to evaluate the kind of food and airborne allergens which may most often induce and intensify AD lesions and also to assess the variability and the kind of allergens leading to AD. The subjects of this study were 610 persons, aged 3 months-70 years. The clinical status of the patients was estimated by an atopic dermatitis symptom score scale (SCORAD). The laboratory examinations differentiated inflammatory processes from allergic reactions. The skin prick tests (SPT), serum total IgE and specific IgE-antibody levels to chosen food products and standard airborne allergens with the immuno-enzymes method ELISA-DPC were performed. The elevated values of the total IgE were proved in 46.1% children from group 0-15 years and in 31.4% of adolescents and adult persons (above 15 year of age). On the basis of positive SPT and positive specific IgE values it was shown, that most frequent food allergens were: egg protein (13.0%), cow milk (9.5%), egg yolk (8.4%), wheat (3.6%) and chocolate (1.8%). The most often airborne allergens connected with AD were: grass (11.6%), moulds (10.2%), house dust mites (9.3%), pollen like hazel (8.0%) and weeds (6.7%), animal allergens coming from cats (7.2%) and dogs (6.1%). The food hypersensitivity was particularly manifested in children. It may be the predictor of potential future development of allergic disease as well as the indicator of the allergic march.

  7. Safety of allergen immunotherapy: a review of premedication and dose adjustment.

    Science.gov (United States)

    Morris, A Erika; Marshall, Gailen D

    2012-03-01

    From the first allergen immunotherapy proposed in the early 1900s to the present day, numerous studies have proven the efficacy of allergen immunotherapy for the treatment of allergic rhinitis, allergic conjunctivitis, allergic asthma and stinging insect hypersensitivity. The major risk, however small, with allergen immunotherapy is anaphylaxis. There has been considerable interest and debate regarding risk factors for immunotherapy reactions (local and systemic) and interventions to reduce the occurrence of these reactions. One of these interventions that is especially debated regards dose adjustment for various reasons, but in particular for local reactions. In this review, we discuss the safety of immunotherapy and provide a comprehensive review of the literature regarding immunotherapy schedules and doses.

  8. Primary structure of Lep d I, the main Lepidoglyphus destructor allergen.

    Science.gov (United States)

    Varela, J; Ventas, P; Carreira, J; Barbas, J A; Gimenez-Gallego, G; Polo, F

    1994-10-01

    The most relevant allergen of the storage mite Lepidoglyphus destructor (Lep d I) has been characterized. Lep d I is a monomer protein of 13273 Da. The primary structure of Lep d I was determined by N-terminal Edman degradation and partially confirmed by cDNA sequencing. Sequence polymorphism was observed at six positions, with non-conservative substitutions in three of them. No potential N-glycosylation site was revealed by peptide sequencing. The 125-residue sequence of Lep d I shows approximately 40% identity (including the six cysteines) with the overlapping regions of group II allergens from the genus Dermatophagoides, which, however, do not share common allergenic epitopes with Lep d I.

  9. Deposition of carbon nanotubes onto aramid fibers using as-received and chemically modified fibers

    International Nuclear Information System (INIS)

    Rodríguez-Uicab, O.; Avilés, F.; Gonzalez-Chi, P.I; Canché-Escamilla, G.; Duarte-Aranda, S.; Yazdani-Pedram, M.; Toro, P.; Gamboa, F.; Mazo, M.A.; Nistal, A.; Rubio, J.

    2016-01-01

    Highlights: • The surface of aramid fibers was functionalized by two acid treatments. • The treatment based on HNO_3/H_2SO_4 reduced the mechanical properties of the fibers. • CNTs were deposited on the aramid fibers, reaching electrical conductivity. • Homogeneous CNT distribution was achieved by using pristine fibers or chlorosulfonic acid. - Abstract: Multiwall carbon nanotubes (MWCNTs) oxidized by an acid treatment were deposited on the surface of as-received commercial aramid fibers containing a surface coating (“sizing”), and fibers modified by either a chlorosulfonic treatment or a mixture of nitric and sulfuric acids. The surface of the aramid fiber activated by the chemical treatments presents increasing density of CO, COOH and OH functional groups. However, these chemical treatments reduced the tensile mechanical properties of the fibers, especially when the nitric and sulfuric acid mixture was used. Characterization of the MWCNTs deposited on the fiber surface was conducted by scanning electron microscopy, Raman spectroscopy mapping and X-ray photoelectron spectroscopy. These characterizations showed higher areal concentration and more homogeneous distribution of MWCNTs over the aramid fibers for as-received fibers and for those modified with chlorosulfonic acid, suggesting the existence of interaction between the oxidized MWCNTs and the fiber coating. The electrical resistance of the MWCNT-modified aramid yarns comprising ∼1000 individual fibers was in the order of MΩ/cm, which renders multifunctional properties.

  10. Application of porous foams for size-selective measurements of airborne wheat allergen

    NARCIS (Netherlands)

    Bogdanovic, J.; Pater, A.J. de; Doekes, G.; Wouters, I.M.; Heederik, D.J.J.

    2006-01-01

    Background: Exposure to airborne wheat allergen is a well-known cause of bakers' allergy and asthma. Airborne wheat allergen can be measured by enzyme immunoassays (EIAs) in extracts of inhalable dust samples, but only limited knowledge is available on the size distribution of wheat

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

    Science.gov (United States)

    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.

  12. Patch test study of 90 patients with tattoo reactions: negative outcome of allergy patch test to baseline batteries and culprit inks suggests allergen(s) are generated in the skin through haptenization.

    Science.gov (United States)

    Serup, Jørgen; Hutton Carlsen, Katrina

    2014-11-01

    Tattoo reactions, especially in red tattoos, are often suggested as allergic in nature, however, systematic evaluation by patch testing has not performed in the past. To report the results of patch testing in 90 patients with non-infectious chronic tattoo reactions. From 2009 to 2013 at the 'Tattoo Clinic', Department of Dermatology, Bispebjerg University Hospital, 90 patients were patch tested with batteries of baseline allergens, disperse dyes/textile allergens, and a selection of tattoo ink stock products, which, according to case observations, were problematic, supplemented with individual culprit inks when accessible. Patients with reactions to the tattoo colour red, the most predominant colour associated with skin reactions, showed negative patch test results with common allergens. Outcomes were also negative in patients who had experienced concomitant reactions in another hitherto tolerated tattoo of the same colour as the problematic tattoo. The allergen or allergens responsible for tattoo reactions are not present directly in tattoo ink stock products. This is despite the fact that clinical histories suggest that the vast majority of clinical reactions, especially reactions to red and red nuances, are likely to be allergic events caused by the injected inks. We suggest that the responsible allergen results from a complicated and slow process of haptenization, which may even include photochemical cleavage of red azo pigment. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Allergenic potential of novel proteins - What can we learn from animal production?

    Science.gov (United States)

    Ekmay, Ricardo D; Coon, Craig N; Ladics, Gregory S; Herman, Rod A

    2017-10-01

    Currently, risk assessment of the allergenic potential of novel proteins relies heavily on evaluating protein digestibility under normal conditions based on the theory that allergens are more resistant to gastrointestinal digestion than non-allergens. There is also proposed guidance for expanded in vitro digestibility assay conditions to include vulnerable sub-populations. One of the underlying rationales for the expanded guidance is that current in vitro assays do not accurately replicate the range of physiological conditions. Animal scientists have long sought to predict protein and amino acid digestibility for precision nutrition. Monogastric production animals, especially swine, have gastrointestinal systems similar to humans, and evaluating potential allergen digestibility in this context may be beneficial. Currently, there is no compelling evidence that the mechanisms sometimes postulated to be associated with allergenic sensitization, e.g. antacid modification of stomach pH, are valid among production animals. Furthermore, examples are provided where non-biologically representative assays are better at predicting protein and amino acid digestibility compared with those designed to mimic in vivo conditions. Greater emphasis should be made to align in vitro assessments with in vivo data. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  14. Food allergen analysis for processed food using a novel extraction method to eliminate harmful reagents for both ELISA and lateral-flow tests.

    Science.gov (United States)

    Ito, Kaori; Yamamoto, Takayuki; Oyama, Yuriko; Tsuruma, Rieko; Saito, Eriko; Saito, Yoshikazu; Ozu, Takeshi; Honjoh, Tsutomu; Adachi, Reiko; Sakai, Shinobu; Akiyama, Hiroshi; Shoji, Masahiro

    2016-09-01

    Enzyme-linked immunosorbent assay (ELISA) is commonly used to determine food allergens in food products. However, a significant number of ELISAs give an erroneous result, especially when applied to highly processed food. Accordingly, an improved ELISA, which utilizes an extraction solution comprising the surfactant sodium lauryl sulfate (SDS) and reductant 2-mercaptoethanol (2-ME), has been specially developed to analyze food allergens in highly processed food by enhancing analyte protein extraction. Recently, however, the use of 2-ME has become undesirable. In the present study, a new extraction solution containing a human- and eco-friendly reductant, which is convenient to use at the food manufacturing site, has been established. Among three chemicals with different reducing properties, sodium sulfite, tris(3-hydroxypropyl)phosphine, and mercaptoethylamine sodium sulfite was selected as a 2-ME substitute. The protein extraction ability of SDS/0.1 M sodium sulfite solution was comparable to that of SDS/2-ME solution. Next, the ELISA performance for egg, milk, wheat, peanut, and buckwheat was evaluated by using model-processed foods and commercially available food products. The data showed that the SDS/0.1 M sulfite ELISA significantly correlated with the SDS/2-ME ELISA for all food allergens examined (p analysis of food allergens in processed food, showing consistency with the SDS/0.1 M sulfite ELISA results. Accordingly, a harmonized analysis system for processed food comprising a screening LF test and a quantitative ELISA with identical extraction solution has been established. The ELISA based on the SDS/0.1 M sulfite extraction solution has now been authorized as the revised official method for food allergen analysis in Japan.

  15. IgG binding of mugwort pollen allergens and allergoids exposed to simulated gastrointestinal conditions measured by a self-developed ELISA test

    OpenAIRE

    RATKO M. JANKOV; OLGA VUCKOVIC; DANICA DJERGOVIC-PETROVIC; LIDIJA BURAZER; TANJA D. CIRKOVICVELICKOVIC; MARIJA DJ. GAVROVIC-JANKULOVIC; NATALIJA DJ. POLOVIC

    2004-01-01

    This study considers the influence of exposure to simulated gastrointestinal conditions (saliva, gut, intestine and acidic conditions of the gut) on IgG binding of unmodified allergens and three types of LMW allergoids of Artemisia vulgaris pollen extract obtained by means of potassium cyanate, succinic and maleic anhydride. It also concerns the optimization of a self-developed ELISA assay for comparison of the specific IgG binding of mugwort pollen extract and modified mugwort pollen derivat...

  16. Depigmented and polymerised house dust mite allergoid: allergen content, induction of IgG4 and clinical response.

    Science.gov (United States)

    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.

  17. [Frequency of skin reactivity to food allergens in allergic patients].

    Science.gov (United States)

    Camero-Martínez, Heriberto; López-García, Aída Inés; Rivero-Yeverino, Daniela; Caballero-López, Chrystopherson Gengyny; Arana-Muñoz, Oswaldo; Papaqui-Tapia, Sergio; Rojas-Méndez, Isabel Cristina; Vázquez-Rojas, Elizabeth

    2017-01-01

    Food allergy is deemed to have a worldwide prevalence ranging from 2 to 10 %. To determine the frequency of skin reactivity to food allergens by age groups. Cross-sectional, descriptive, prolective, observational study. Patients aged from 2 to 64 years with symptoms consistent with allergic disease were included. Skin prick tests were carried out with food allergens. Frequencies and percentages were estimated. One-hundred and ninety-one patients were included, out of which 63.4% were females. Mean age was 22.5 years; 19.3 % showed positive skin reactivity to at least one food. Distribution by age group was as follows: preschool children 13.5 %, schoolchildren 24.3 %, adolescents 2.7 % and adults 59.5 %. Diagnoses included allergic rhinitis in 84.3 %, asthma in 19.4 %, urticaria in 14.1 % and atopic dermatitis in 8.4 %. Positive skin reactivity frequency distribution in descending order was: soybeans with 5.2 %, peach with 4.7 %, grapes, orange and apple with 3.6 %, nuts with 3.1 %, pineapple, avocado, tomato and tuna with 2.6 %. The frequency of skin reactivity to food allergens was similar to that reported in the national and Latin American literature, but sensitization to each specific allergen varied for each age group.

  18. Identification of Lilial as a fragrance sensitizer in a perfume by bioassay-guided chemical fractionation and structure-activity relationships.

    Science.gov (United States)

    Arnau, E G; Andersen, K E; Bruze, M; Frosch, P J; Johansen, J D; Menné, T; Rastogi, S C; White, I R; Lepoittevin, J P

    2000-12-01

    Fragrance materials are among the most common causes of allergic contact dermatitis. The aim of this study was to identify in a perfume fragrance allergens not included in the fragrance mix, by use of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships (SARs). The basis for the investigation was a 45-year-old woman allergic to her own perfume. She had a negative patch test to the fragrance mix and agreed to participate in the study. Chemical fractionation of the perfume concentrate was used for repeated patch testing and/or repeated open application test on the pre-sensitized patient. The chemical composition of the fractions giving a positive patch-test response and repeated open application test reactions was obtained by gas chromatography-mass spectrometry. From the compounds identified, those that contained a "structural alert" in their chemical structure, indicating an ability to modify skin proteins and thus behave as a skin sensitizer, were tested on the patient. The patient reacted positively to the synthetic fragrance p-t-butyl-alpha-methylhydrocinnamic aldehyde (Lilial), a widely used fragrance compound not present in the fragrance mix. The combination of bioassay-guided chemical fractionation and chemical analysis/structure-activity relationships seems to be a valuable tool for the investigation of contact allergy to fragrance materials.

  19. Fast real-time PCR for the detection of crustacean allergen in foods.

    Science.gov (United States)

    Herrero, Beatriz; Vieites, Juan M; Espiñeira, Montserrat

    2012-02-29

    Crustaceans are one of the most common allergens causing severe food reaction. These food allergens are a health problem, and they have become very important; there are various regulations that establish that labeling must be present regarding these allergens to warn consumers. In the present work a fast real-time PCR, by a LNA probe, was developed. This allows the detection of crustaceans in all kinds of products, including processed products in which very aggressive treatments of temperature and pressure during the manufacturing process are used. This methodology provides greater sensitivity and specificity and reduces the analysis time of real-time PCR to 40 min. This methodology was further validated by means of simulating products likely to contain this allergen. For this, products present on the market were spiked with crustacean cooking water. The assay is a potential tool in issues related to the labeling of products and food security to protect the allergic consumer.

  20. Contents of fragrance allergens in children's cosmetics and cosmetic-toys

    DEFF Research Database (Denmark)

    Rastogi, S C; Johansen, Jeanne Duus; Menné, T

    1999-01-01

    was present in a maximum concentration of 0.07%. In one cosmetic-toy, cinnamic alcohol was present at 3.7% which exceeds the current industry guideline for safe products by a factor of 5. In all types of products other fragrance allergens were frequently found. In conclusion, children are already exposed......Fragrances are one of the major causes of allergic contact dermatitis from use of cosmetics. The aim of the current study was to assess the possible exposure of infants and children to fragrance allergens from cosmetic products and "toy-cosmetics". 25 children's cosmetics or toy-cosmetic products...... at an early age to well-known allergens, sometimes at concentrations which are considered to be unsafe. As contact allergy usually persists for life, manufacturers of children's cosmetics should be aware of their special responsibility and apply the highest possible safety standards....