Food Allergens (food + allergen)

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Food Allergens

  • common food allergen


  • Selected Abstracts


    Immunoglobulin-E Reactivity to a Glycosylated Food Allergen (Peanuts) Due to Interference With Cross-Reactive Carbohydrate Determinants in Heavy Drinkers

    ALCOHOLISM, Issue 8 2009
    C. Vidal
    Background:, N-glycans in plant and invertebrate glycoproteins can induce extensive IgE cross-reactivity therefore limiting the specificity of in vitro allergy tests. IgE sensitization to N-glycans (cross-reactive carbohydrate determinants, CCDs) may be increased in heavy drinkers, who therefore show IgE reactivity to aeroallergens, latex, and Hymenoptera venoms. The peanut, a CCD-bearing allergen, is the leading cause of severe food allergic reactions in many populations. Aim of the study:, To investigate the potential interference of CCDs with determinations of IgE to peanuts in heavy drinkers. Methods:, We determined IgE to peanuts and IgE to a CCD marker (MUXF3, the N-glycan from bromelain) in 41 heavy drinkers admitted to the hospital and 54 healthy controls. None of the participants reported symptoms of peanut allergy. In cases with positive (,0.35 kU/l) IgE to peanuts, we performed inhibition assays with a neoglycoprotein consisting of MUXF3 molecules coupled to bovine serum albumin (MUXF3 -BSA) and a similar neoglycoprotein lacking xylose and fucose (MM-BSA). In the same cases, we screened for IgE to a panel of recombinant nonglycosylated peanut allergens. SDS-PAGE immunoblotting and inhibition assays were performed in selected cases. Results:, The prevalence of positive IgE to peanuts was 22 and 3.7% in heavy drinkers and healthy controls, respectively (p < 0.001). Peanut-IgE positivity was closely related to the presence of IgE to CCDs. In most (8/9) heavy drinkers with positive IgE to peanuts, reactivity was inhibited by preincubation with MUXF3 -BSA, but not with MM-BSA. IgE binding to multiple bands on immunoblotting studies was also inhibited by MUXF3 -BSA preincubation. IgE to nonglycosylated recombinant peanut allergens was uniformly negative. Conclusion:, Heavy drinking is associated with clinically asymptomatic IgE reactivity to peanuts, a relevant food allergen, in relation to CCD interference. [source]


    Bet,v,1, the major birch pollen allergen, initiates sensitization to Api,g,1, the major allergen in celery: evidence at the T,cell level

    EUROPEAN JOURNAL OF IMMUNOLOGY, Issue 12 2003
    Barbara Bohle
    Abstract Due to IgE cross-reactivity, birch pollen-allergic individuals frequently develop type,I hypersensitivity reactions to celery tuber. We evaluated the T,cell response to the major allergen in celeriac, Api,g,1, and the cellular cross-reactivity with its homologous major allergen in birch pollen, Bet,v,1. Api,g,1-specific T,cell lines (TCL) and clones (TCC) were established from peripheralblood mononuclear cells of allergic patients. Epitope mapping of Api,g,1 with overlapping Api,g,1-derived peptides revealed one dominant T,cell-activating region, Api,g,1109,126. TCL and TCC generated with Api,g,1 cross-reacted with the birch pollen allergen and, although initially stimulated with the food allergen, cellular responses to Bet,v,1 were stronger than to Api,g,1. Epitopemapping with Bet,v,1-derived peptides revealed that T,cells specific for several distinct epitopes distributed over the complete Bet,v,1 molecule could be activated by Api,g,1. Bet,v,1109,126 was identified as the most important T,cell epitope for cross-reactivity with Api,g,1. This epitope shares 72% amino acid sequence similarity with the major T,cell-activating region of the food allergen, Api,g,1109,126. Our data provide evidence that humoral as well as cellular reactivity to the major celery allergen is predominantly based on cross-reactivity with the major birch pollen allergen. The activation of Bet,v,1-specific Th2 cells by Api,g,1, in particular outside the pollen season, may have consequences for birch pollen-allergic individuals. [source]


    Food allergy in adolescents and adults

    INTERNAL MEDICINE JOURNAL, Issue 7 2009
    J. Yun
    Abstract There has been an increase in the prevalence of food allergy in the last few decades. Adult food allergy may represent persistence of reactions that commenced in infancy and early childhood or it may be initiated in adulthood through new sensitizations. Persistence of peanut allergy is an example of the former situation. Approximately 20% of children will develop tolerance to peanuts, so there will be an increasing number of individuals reaching adulthood where this problem will need ongoing management. In addition to peanut, tree nuts, fruits, vegetables and seafood are implicated as common causes of food allergy in adulthood. Sensitization may occur directly to a food allergen or indirectly through cross-reactivity with an aeroallergen. Adults may present with a spectrum of clinical manifestations from oral allergy syndrome to fatal anaphylaxis. The management of food allergy consists of appropriate education regarding avoidance of implicated foods, modifying potential risk factors for anaphylaxis, such as asthma and prompt recognition and treatment of acute reactions. [source]


    Immunoglobulin-E Reactivity to a Glycosylated Food Allergen (Peanuts) Due to Interference With Cross-Reactive Carbohydrate Determinants in Heavy Drinkers

    ALCOHOLISM, Issue 8 2009
    C. Vidal
    Background:, N-glycans in plant and invertebrate glycoproteins can induce extensive IgE cross-reactivity therefore limiting the specificity of in vitro allergy tests. IgE sensitization to N-glycans (cross-reactive carbohydrate determinants, CCDs) may be increased in heavy drinkers, who therefore show IgE reactivity to aeroallergens, latex, and Hymenoptera venoms. The peanut, a CCD-bearing allergen, is the leading cause of severe food allergic reactions in many populations. Aim of the study:, To investigate the potential interference of CCDs with determinations of IgE to peanuts in heavy drinkers. Methods:, We determined IgE to peanuts and IgE to a CCD marker (MUXF3, the N-glycan from bromelain) in 41 heavy drinkers admitted to the hospital and 54 healthy controls. None of the participants reported symptoms of peanut allergy. In cases with positive (,0.35 kU/l) IgE to peanuts, we performed inhibition assays with a neoglycoprotein consisting of MUXF3 molecules coupled to bovine serum albumin (MUXF3 -BSA) and a similar neoglycoprotein lacking xylose and fucose (MM-BSA). In the same cases, we screened for IgE to a panel of recombinant nonglycosylated peanut allergens. SDS-PAGE immunoblotting and inhibition assays were performed in selected cases. Results:, The prevalence of positive IgE to peanuts was 22 and 3.7% in heavy drinkers and healthy controls, respectively (p < 0.001). Peanut-IgE positivity was closely related to the presence of IgE to CCDs. In most (8/9) heavy drinkers with positive IgE to peanuts, reactivity was inhibited by preincubation with MUXF3 -BSA, but not with MM-BSA. IgE binding to multiple bands on immunoblotting studies was also inhibited by MUXF3 -BSA preincubation. IgE to nonglycosylated recombinant peanut allergens was uniformly negative. Conclusion:, Heavy drinking is associated with clinically asymptomatic IgE reactivity to peanuts, a relevant food allergen, in relation to CCD interference. [source]


    Prevalence and distribution of sensitization to foods in the European Community Respiratory Health Survey: a EuroPrevall analysis

    ALLERGY, Issue 9 2010
    P. Burney
    To cite this article: Burney P, Summers C, Chinn S, Hooper R, van Ree R, Lidholm J. Prevalence and distribution of sensitization to foods in the European Community Respiratory Health Survey: a EuroPrevall analysis. Allergy 2010; 65: 1182,1188. Abstract Background:, Reports of adverse reactions to foods are increasing, but there is limited information on the comparative prevalence of sensitization to food allergens using standardized methods. Methods:, Sera from the ,random sample' of young adults seen during the second phase of the European Community Respiratory Health Survey were analysed for IgE against 24 foods using ImmunoCAP. Sera were tested on five food mixes, and subsequently on individual foods in each positive mix. Results:, Sera from 4522 individuals living in 13 countries were tested for at least one food allergen mix. Prevalence of sensitization to any of the 24 food allergens ranged from 24.6% in Portland (USA) to 7.7% in Reykjavik (Iceland). With few exceptions, the relative prevalence of sensitization to different foods was similar in all countries. Sensitization rates to egg, fish and milk were each less than 1%, and the most common sensitizations are not represented in current commercial mixes. The prevalence of sensitization to foods was not related to that of sensitization to aeroallergens but was related to the geometric mean total IgE for the country. Conclusions:, Sensitization to foods is common but highly variable. The relative prevalence of sensitization to different foods is more consistent than would be expected by chance, suggesting that quantity of consumption of specific foods does not determine prevalence. The aetiology of food sensitization is only partly similar to that for aeroallergens but is related to local levels of total IgE. This may provide an important clue to the origins of food sensitization. [source]


    Lupine, a source of new as well as hidden food allergens

    MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 1 2010
    Uta Jappe
    Abstract The present review summarizes current knowledge about lupine allergy, potential sensitization routes, cross-reactions between lupine and other legumes, and the respective IgE-binding proteins. Since the 1990s, lupine flour is used as a substitute for or additive to other flours, mostly wheat flour, in several countries of the EU. In 1994, the first case of an immediate-type allergy after ingestion of lupine flour-containing pasta was reported. Since then, the number of published incidents following ingestion or inhalation of lupine flour is rising. So far, the Lupinus angustifolius ,-conglutin has been designated as the allergen Lup an 1 by the International Union of Immunological Societies Allergen Nomenclature Subcommittee. Initially, publications focussed on the fact that peanut-allergic patients were at risk to develop anaphylaxis to lupine due to cross-reactivity between peanut and lupine. At present, however, the ratio between cases of pre-existing legume allergy (mostly peanut allergy) to de novo sensitization to lupine seed is nearly 1:1. Although in December 2006, lupine and products thereof were included in the EU foodstuff allergen list according to the Commission Directive 2006/142/EC amending Annex IIIA of Directive 2000/13/EC in order to prevent severe reactions caused by "hidden food allergens", the majority of patients and medical personnel are still not aware of raw lupine seed as potentially dangerous food allergen. [source]


    Dysregulated Th1 and Th2 responses in food-allergic children , Does elimination diet contribute to the dysregulation?

    PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 4p1 2010
    Sara Tomi
    Tomi,i, S, Fälth-Magnusson K, Fagerås Böttcher M. Dysregulated Th1 and Th2 responses in food-allergic children , does elimination diet contribute to the dysregulation? Pediatr Allergy Immunol 2010: 21: 649,655. © 2010 John Wiley & Sons A/S Infants with eczema and sensitization to foods are recommended skin care and, if food allergy is proven, an elimination diet. Although most of these children tolerate foods before 3 yr of age, some children experience prolonged food allergy. To our knowledge, no prospective study has investigated the cytokine profile in food-sensitized eczematous children with prolonged food intolerance. The aim of the study was to prospectively investigate the development of cytokine production induced by food allergen in food-sensitized eczematous children who, at 4½ yr of age, were allergic or tolerant to egg or milk. Twenty-one eczematous infants, [age 5 (3,10) months; median and range], sensitized to egg and/or milk were included, put on elimination diet and followed prospectively. At 4½ yr of age, the children were defined as tolerant or allergic to egg and/or milk based on open or double-blind placebo-controlled food challenges. Peripheral blood mononuclear cells (PBMC) were isolated from the children on inclusion, after 6 wk of elimination diet, and at 3 and 4½ yr of age. Ovalbumin, ,-lactoglobulin and tetanus toxoid-induced IL-4, -5, -10, -13 and IFN-, production from PBMC were analyzed with enzyme-linked immunosorbent assay. The IFN-, and IL-5 secretion induced by food allergen at 4½ yr was higher in cell cultures from children who were allergic to egg or milk than in tolerant children. In food-allergic children, the levels of IFN-, and IL-5 were higher at 4½ yr compared with inclusion levels, but this increase was generally not observed in the tolerant children who consumed milk and egg. In conclusion, immune cells from food-allergic children on an elimination diet respond with up-regulated T helper 1 and T helper 2 cytokine secretion induced by food allergen. We hypothesize that allergen elimination may influence the regulatory mechanisms maintaining balanced immune responses to innocuous food antigens. [source]


    Characterization of peach thaumatin-like proteins and their identification as major peach allergens

    CLINICAL & EXPERIMENTAL ALLERGY, Issue 9 2010
    A. Palacín
    Summary Background Peach is the most important fruit related to food allergy in the Mediterranean area. Pru p 3, its lipid transfer protein, has been described as the principal allergen responsible for cross-reactivities with other foods and pollen and the severity of clinical symptoms. However, the involvement of other allergenic families cannot be ruled out. Thaumatin-like proteins (TLPs) have been described as food allergen in several fruits, such as apple, cherry, kiwi and banana, and pollen. Objective To identify members of the TLP family in peach fruit and to characterize putative allergens. Methods Through two-dimensional (2D) electrophoresis of peach extract and immunodetections with a pool of peach-allergic patients, IgE-binding spots were identified and the corresponding proteins purified and characterized as allergens by in vitro and in vivo assays. Three isoforms, belonging to the TLP family, were purified by different chromatographic systems and characterized by N -terminal amino acid sequences, molecular weight determination (MALDI) and enzymatic activity analysis (,-1,3-gluconase test and inhibition growth of fungi). In the same way, their IgE-binding capacity and allergenic activity were tested by ELISA assays, basophil activation tests and skin prick tests (SPT). Results Two peach-TLPs, Pru p 2.0101 and Pru p 2.0201, were identified as IgE-binding spots by 2D electrophoresis. Another peach-TLP, Pru p 2.0301, was cloned and produced as recombinant protein in a yeast system. The three isoforms were purified and characterized as TLPs by immunoblotting with anti-chestnut TLP antibodies and anti-plant N -asparagine complex glycan (anti-cross-reactive carbohydrate determinant). All of them showed ,-1,3-glucanase activity and inhibition of fungal growth. The three TLPs were recognized by around 50% of the sera from 31 patients analysed in ELISA experiments. All three gave a positive response to an SPT and/or in basophil activation experiments. Conclusion Three isoforms, belonging to the TLP family, were identified in peach as principal allergens. Their prevalence, observed in in vitro, ex vivo and in vivo analyses, suggests that they are important allergens and should therefore be included in the routine diagnosis of peach allergy, at least in the Mediterranean area. Cite this as: A. Palacín, L. Tordesillas, P. Gamboa, R. Sanchez-Monge, J. Cuesta-Herranz, M. L. Sanz, D. Barber, G. Salcedo and A. Díaz-Perales, Clinical & Experimental Allergy, 2010 (40) 1422,1430. [source]


    CD4+ T cells from mice with intestinal immediate-type hypersensitivity induce airway hyperreactivity

    CLINICAL & EXPERIMENTAL ALLERGY, Issue 10 2007
    C. Ozdemir
    Summary Background A subset of food-allergic patients does not only respond clinically with symptoms in the gastro-intestinal tract but also with asthmatic reactions. Objective The aim of this study was to analyse whether CD4+ T cells from mice with intestinal immediate-hypersensitivity reactions to food allergen are involved in the development of experimental asthma. Methods BALB/c mice were intraperitoneally sensitized to ovalbumin (OVA), followed by repeated intra-gastric (i.g.) OVA challenges. Control animals were either sham-sensitized or sham-challenged with phosphate-buffered saline (PBS). Duodenum, jejunum, ileum and colon were histologically examined. CD4+ T cells from mesenteric lymph nodes were transferred from various donor groups into recipient mice that received either OVA or PBS aerosol challenges. Recipients were analysed by measurements of lung function using head-out body-plethysmography and examination of broncho-alveolar lavage and lung histology. Results The highest levels of OVA-specific IgE antibody levels were detected in OVA-sensitized and OVA-challenged mice. Throughout the lower intestinal tract, a marked infiltration with eosinophils was observed, and goblet cell numbers as well as goblet cell area were significantly increased. The villus/crypt ratio was decreased compared with controls. The transfer of CD4+ T cells from mesenteric lymph nodes of OVA-sensitized and OVA-challenged mice triggered airway hyperreactivity and eosinophilic airway inflammation in recipients aerosol challenged with OVA, but not with PBS. Conclusion We conclude that CD4+ T cells from mesenteric lymph nodes of mice with allergen-induced immediate-type hypersensitivity reactions in the gut are able to transfer the phenotype of experimental asthma. [source]


    Kiwi fruit is a significant allergen and is associated with differing patterns of reactivity in children and adults

    CLINICAL & EXPERIMENTAL ALLERGY, Issue 7 2004
    J. S. A. Lucas
    Summary Background Allergy to kiwi fruit appears increasingly common, but few studies have evaluated its clinical characteristics, or evaluated methods of investigating the allergy. Objective To characterize the clinical characteristics of kiwi fruit allergy and to study the role of double-blind placebo-controlled food challenge (DBPCFC), skin tests and specific IgE in the diagnosis of this food allergy. Methods Two-hundred and seventy-three subjects with a history suggestive of allergy to kiwi completed a questionnaire. Forty-five were investigated by DBPCFC, prick-to-prick skin testing with fresh kiwi pulp, and specific IgE measurement. Nineteen subjects were also skin tested using a commercially available solution. Results The most frequently reported symptoms were localized to the oral mucosa (65%), but severe symptoms (wheeze, cyanosis or collapse) were reported by 18% of subjects. Young children were significantly more likely than adults to react on their first known exposure (P<0.001), and to report severe symptoms (P=0.008). Twenty-four of 45 subjects (53%) had allergy confirmed by DBPCFC. Prick-to-prick skin test with fresh kiwi was positive in 93% of subjects who had allergy confirmed by DBPCFC, and also in 55% of subjects with a negative food challenge. The commercial extract was significantly less sensitive, but with fewer false-positive reactions. CAP sIgE was only positive in 54% of subjects who had a positive challenge. Conclusions Kiwi fruit should be considered a significant food allergen, capable of causing severe reactions, particularly in young children. DBPCFC confirmed allergy to kiwi fruit in 53% of the subjects tested, who had a previous history suggestive of kiwi allergy. Skin testing with fresh fruit has good sensitivity (93%), but poor specificity (45%) in this population. CAP sIgE and a commercially available skin test solution were both much less sensitive (54%; 75%) but had better specificity (90%; 67%). [source]


    Cover Picture: Electrophoresis 13'2010

    ELECTROPHORESIS, Issue 13 2010
    Article first published online: 30 JUN 2010
    Issue no. 13 is a special issue on "Food and Beverage Analysis" comprising 23 contributions distributed over four distinct parts. Part I "presents six review papers, five of them are focused on the use of capillary electromigration techniques for detecting enantiomers, nucleosides, nucleotides, pesticides and contaminants in foods as well as foodborne pathogens". The sixth review deals with the application of two-dimensional electrophoresis to investigate food allergens. A series of original contributions on the use of CE, CEC and MEKC in the analysis of food constituents are grouped in Part II. Part III presents "Works on the detection of genetically modified foods by CGE and the analysis of antibiotics and antioxidants by microemulsion electrokinetic chromatography". Finally, Part IV is on the use of CE-MS to analyze endocrine disruptors and polyphenols in different food matrices, and on the speciation analysis of arsenic and selenium compounds in different foodstuffs by capillary electrophoresis-inductively coupled plasma-mass spectrometry. [source]


    Capillary electrophoresis for the analysis of contaminants in emerging food safety issues and food traceability

    ELECTROPHORESIS, Issue 13 2010
    Belinda Vallejo-Cordoba
    Abstract This review presents an overview of the applicability of CE in the analysis of chemical and biological contaminants involved in emerging food safety issues. Additionally, CE-based genetic analyzers' usefulness as a unique tool in food traceability verification systems was presented. First, analytical approaches for the determination of melamine and specific food allergens in different foods were discussed. Second, natural toxin analysis by CE was updated from the last review reported in 2008. Finally, the analysis of prion proteins associated with the "mad cow" crises and the application of CE-based genetic analyzers for meat traceability were summarized. [source]


    A novel model of sensitization and oral tolerance to peanut protein

    IMMUNOLOGY, Issue 3 2004
    Jessica Strid
    Summary The prevalence of food allergic diseases is rising and poses an increasing clinical problem. Peanut allergy affects around 1% of the population and is a common food allergy associated with severe clinical manifestations. The exact route of primary sensitization is unknown although the gastrointestinal immune system is likely to play an important role. Exposure of the gastrointestinal tract to soluble antigens normally leads to a state of antigen-specific systemic hyporesponsiveness (oral tolerance). A deviation from this process is thought to be responsible for food-allergic diseases. In this study, we have developed a murine model to investigate immunoregulatory processes after ingestion of peanut protein and compared this to a model of oral tolerance to chicken egg ovalbumin (OVA). We demonstrate that oral tolerance induction is highly dose dependent and differs for the allergenic proteins peanut and OVA. Tolerance to peanut requires a significantly higher oral dose than tolerance to OVA. Low doses of peanut are more likely to induce oral sensitization and increased production of interleukin-4 and specific immunoglobulin E upon challenge. When tolerance is induced both T helper 1 and 2 responses are suppressed. These results show that oral tolerance to peanut can be induced experimentally but that peanut proteins have a potent sensitizing effect. This model can now be used to define regulatory mechanisms following oral exposure to allergenic proteins on local, mucosal and systemic immunity and to investigate the immunomodulating effects of non-oral routes of allergen exposure on the development of allergic sensitization to peanut and other food allergens. [source]


    Food allergic consumers' preferences for labelling practices: a qualitative study in a real shopping environment

    INTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 1 2009
    Jantine Voordouw
    Abstract Food allergy is a chronic disease that can only be managed through avoidance of problematic proteins in the diet. Inappropriate communication about food allergens can cause stress and insecurity, which may have a negative impact on quality of life. The aim was to investigate whether information provided through current labelling practices meets the need of food allergic consumers. A total of 40 participants (20 adult food allergy suffers and 20 parents of food allergic children) were recruited from two different European countries (Greece and The Netherlands), and interviewed while shopping in a supermarket. Participants were asked to purchase 15 potentially problematic food items as if for their own household. Their information search behaviour was observed, and participants were questioned about their preferences for food allergen information provision. Participants reported experiencing problems associated with current food allergy information provision. It was reported that inappropriate use of fonts, colours and languages, application of precautionary labelling and lack of harmonization in labelling practices across countries can cause (un)necessary dietary restrictions for food allergic consumers. Research is needed to investigate the feasibility and implementation possibilities for new information delivery strategies and amendments to existing European labelling policy. [source]


    Evaluation and standardisation of different matrices used for double-blind placebo-controlled food challenges to fish

    JOURNAL OF HUMAN NUTRITION & DIETETICS, Issue 5 2010
    E. Vassilopoulou
    Abstract Background:, Fish allergens represent one of the most common causes of adverse reactions to food worldwide. Double-blind placebo-controlled food challenges (DBPCFC) are the gold standard for food allergy diagnosis. However, no standardised recipes are available for common food allergens such as fish, and a well trained dietitian is essential for creating and standardising them. The present study aimed to create and standardise recipes for use in DBPCFCs to fish. Methods:, Three recipes were prepared. Employing a standardised procedure, a total of 35 panelists evaluated the different matrices using an evaluation form. A paired comparison test was used to estimate total evaluation's outcome. Fish allergic patients were challenged with different fish species blinded with the selected matrix and evaluated the recipe using the same form. Results:, From a base recipe and step-by-step modifications, a low fat recipe was selected among other recipes tested, which proved to be appropriate for fish blinding, in terms of taste, odour, appearance and blinding. Patients challenged with the final matrix found it acceptable, no matter which fish type was used. Conclusions:, In this pilot study, a recipe with satisfactory organoleptic characteristics was developed and validated for DBPCFC to fish. [source]


    Identification of B-cell epitopes of Bet v 1 involved in cross-reactivity with food allergens

    ALLERGY, Issue 4 2009
    E. Klinglmayr
    Background:, The pollen-food syndrome (PFS) is an association of food allergies to fruits, nuts, and vegetables in patients with pollen allergy. Mal d 1, the major apple allergen, is one of the most commonly associated food allergens for birch pollen-allergic patients suffering from PFS. Although the reactions are due to cross-reactive IgE antibodies originally raised against pollen Bet v 1, not every Bet v 1-allergic patient develops clinical reactions towards apple. Aim of the study:, We speculate that distinct IgE epitopes are responsible for the clinical manifestation of PFS. To test this hypothesis we grafted five Mal d 1 stretches onto Bet v 1. The grafted regions were 7- or 8-amino acids long encompassing amino acids residues previously shown to be crucial for IgE recognition of Bet v 1. Methods:, A Bet v 1-Mal d 1 chimeric protein designated BMC was expressed in Escherichia coli and purified to homogeneity. IgE reactivity of BMC was tested with patients' sera originating from (i) Bet v 1-allergic patients displaying no clinical symptoms upon ingestion of apples; and (ii) Bet v 1-allergic patients displaying allergic symptoms upon ingestion of apples and other Bet v 1-related foods. Results and conclusion:, Compared to birch pollen-allergic individuals, patients suffering from PFS showed significantly higher IgE reactivity with BMC (chimeric protein). The results suggest that the Mal d 1 regions grafted onto the Bet v 1 sequence comprise important IgE epitopes recognized by Bet v 1-allergic patients suffering from allergy to apples. [source]


    Specific IgE to allergens in cord blood is associated with maternal immunity to Toxoplasma gondii and rubella virus

    ALLERGY, Issue 11 2008
    M. J. Ege
    Background:, Various studies have found reduced prevalences of atopic sensitization and atopic diseases in children previously exposed to infections or living conditions with a high microbial burden, such as the farming environment. Objective:, We sought to determine the relationships of cord blood immunoglobulin E (IgE) with maternal health conditions before and during pregnancy. Methods:, Pregnant women living in rural areas in five European countries were recruited in the third trimester of pregnancy. Information on maternal health during pregnancy was collected from maternity records and by questionnaires (n = 497). Specific IgE for inhalant and food allergens was assessed in cord blood and peripheral blood samples of the mothers. Results:, Inverse associations of cord blood IgE to seasonal allergens with positive maternal records for Toxoplasma gondii (adjusted odds ratio = 0.37 [0.17,0.81]) and rubella virus (adjusted odds ratio = 0.35 [0.13,0.96]) were found. The previously described effect of prenatal farm exposure on IgE to seasonal allergens was partly confounded by a positive maternal record for T. gondii. The number of maternal siblings, maternal contact to cats during pregnancy or during her first year of life, predicted a positive maternal record for T. gondii. Conclusions:, Maternal immunity to T. gondii and rubella may impact on atopic sensitization in the fetus. A positive T. gondii record explained the previously identified effect of prenatal farm exposure on IgE to seasonal allergens only to a minor extent. [source]


    Thresholds for food allergens and their value to different stakeholders

    ALLERGY, Issue 5 2008
    R. W. R Crevel
    Thresholds constitute a critical piece of information in assessing the risk from allergenic foods at both the individual and population levels. Knowledge of the minimum dose that can elicit a reaction is of great interest to all food allergy stakeholders. For allergic individuals and health professionals, individual threshold data can inform allergy management. Population thresholds can help both the food industry and regulatory authorities assess the public health risk and design appropriate food safety objectives to guide risk management. Considerable experience has been gained with the double-blind placebo-controlled food challenge (DBPCFC), but only recently has the technique been adapted to provide data on thresholds. Available data thus vary greatly in quality, with relatively few studies providing the best quality individual data, using the low-dose DBPCFC. Such high quality individual data also form the foundation for population thresholds, but these also require, in addition to an adequate sample size, a good characterization of the tested population in relation to the whole allergic population. Determination of thresholds at both an individual level and at a population level is influenced by many factors. This review describes a low-dose challenge protocol developed as part of the European Community-funded Integrated Project Europrevall, and strongly recommends its wider use so that data are generated that can readily increase the power of existing studies. [source]


    Eczematous reactions to food in atopic eczema: position paper of the EAACI and GA2LEN

    ALLERGY, Issue 7 2007
    T. Werfel
    Food allergy and atopic eczema (AE) may occur in the same patient. Besides typical immediate types of allergic reactions (i.e. noneczematous reactions) which are observed in patients suffering from AE, it is clear that foods, such as cow's milk and hen's eggs, can directly provoke flares of AE, particularly in sensitized infants. In general, inhaled allergens and pollen-related foods are of greater importance in older children, adolescents and adults. Clinical studies have revealed that more than 50% of affected children with AE that can be exacerbated by certain foods will react with a worsening of skin eczema either alone or in addition to immediate symptoms. Adolescents and adults may also react to foods, but reactions to ,classical' food allergens, such as hen's eggs and cow's milk, are not as common as in childhood. Some patients with AE do react to pollen-associated foods. Food-induced eczema should not be neglected by the allergologist: On the one hand, food can be a relevant trigger factor of persistent moderate-to-severe AE; on the other hand, unnecessary diets which are not based on a proper diagnosis may lead to malnutrition and additional psychological stress on patients suffering from AE. Eczematous reactions to food can only be diagnosed by a thorough diagnostic procedure, taking into account the patient's history, the degree of sensitization and the clinical relevance of the sensitization. The latter has often to be proven by oral food challenges. Upon oral food challenge it is most important to evaluate the status of the skin with an established score (e.g. SCORAD, EASI) after 24 h and later because otherwise worsening of eczema will be missed. [source]


    The impact of pollen-related food allergens on pollen allergy

    ALLERGY, Issue 1 2007
    B. Bohle
    Patients with birch pollen allergy frequently develop hypersensitivity reactions to certain foods, e.g. apples, celery, carrots and hazelnuts. These reactions are mainly caused by IgE-antibodies specific for the major birch pollen allergen, Bet v 1, which cross-react with homologous proteins in these foods. Analyzing the T-cell response to Bet v 1-related food allergens revealed that these dietary proteins contain several distinct T-cell epitopes and activate Bet v 1-specific T cells to proliferate and produce cytokines. Several of these cross-reactive T-cell epitopes were not destroyed by simulated gastrointestinal digestion of food allergens and stimulated Bet v 1-specific T cells despite nonreactivity with IgE antibodies. Similarly, cooked food allergens did not elicit IgE-mediated symptoms (oral allergy syndromes) but caused T-cell-mediated late-phase reactions (deterioration of atopic eczema) in birch pollen-allergic patients with atopic dermatitis because thermal processing affected their conformational structure and not the primary amino acid sequence. Thus, T-cell cross-reactivity between Bet v 1 and related food allergens occurs independently of IgE-cross-reactivity in vitro and in vivo. We speculate that symptom-free consumption of pollen-related food allergens may have implications for the pollen-specific immune response of allergic individuals. [source]


    Screening the allergenic repertoires of wheat and maize with sera from double-blind, placebo-controlled food challenge positive patients

    ALLERGY, Issue 1 2006
    M. Weichel
    Background:, Food allergy to wheat and maize is an increasing factor of deterioration of life quality, especially childhood and can, in rare cases, even induce anaphylaxis. Although omega-5 gliadin from wheat and maize lipid transfer protein have been characterized as major cereal allergens on the molecular level, the list of food allergens is far to be complete. Methods:, To identify the IgE-binding repertoires of wheat and maize we screened respective cDNA libraries displayed on phage surface with sera from patients with a confirmed food allergy. The study included six patients with a positive double-blind, placebo-controlled food challenge (DBPCFC) to wheat, nine patients with a positive DBPCFC to maize, and six patients with anaphylactic reactions after ingestion of wheat. Results:, The enriched sequences encoding IgE-binding proteins showed heterogeneous repertoires for both, wheat and maize. The selected wheat repertoire yielded 12, the maize repertoire 11 open reading frames. Among these we identified allergens belonging to already characterized allergens families, such as gliadin, profilin and beta-expansin. Besides, we found novel proteins with high cross-reactive potential, such as thioredoxins, as well as sequences that had so far not been related to cereal allergy at all. The IgE-binding capacity of some selected proteins was evaluated in vitro and cross-reactivity was demonstrated by competition ELISA. Conclusion:, With regard to the heterogeneity of the characterized sequences as well as to the biochemical nature of the new allergens detected we conclude that wheat and maize-related food allergy is more complex than so far anticipated. [source]


    EU Regulation: What's new in terms of labelling of food allergens?

    ALLERGY, Issue 12 2004
    J. Humières
    No abstract is available for this article. [source]


    Lupine, a source of new as well as hidden food allergens

    MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 1 2010
    Uta Jappe
    Abstract The present review summarizes current knowledge about lupine allergy, potential sensitization routes, cross-reactions between lupine and other legumes, and the respective IgE-binding proteins. Since the 1990s, lupine flour is used as a substitute for or additive to other flours, mostly wheat flour, in several countries of the EU. In 1994, the first case of an immediate-type allergy after ingestion of lupine flour-containing pasta was reported. Since then, the number of published incidents following ingestion or inhalation of lupine flour is rising. So far, the Lupinus angustifolius ,-conglutin has been designated as the allergen Lup an 1 by the International Union of Immunological Societies Allergen Nomenclature Subcommittee. Initially, publications focussed on the fact that peanut-allergic patients were at risk to develop anaphylaxis to lupine due to cross-reactivity between peanut and lupine. At present, however, the ratio between cases of pre-existing legume allergy (mostly peanut allergy) to de novo sensitization to lupine seed is nearly 1:1. Although in December 2006, lupine and products thereof were included in the EU foodstuff allergen list according to the Commission Directive 2006/142/EC amending Annex IIIA of Directive 2000/13/EC in order to prevent severe reactions caused by "hidden food allergens", the majority of patients and medical personnel are still not aware of raw lupine seed as potentially dangerous food allergen. [source]


    Cover Picture , Mol.

    MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue S2 2008
    Nutr.
    Diagnosis of food allergy depends on the quality of allergen preparations. Unfortunately, in many cases the quality of food allergen material used is poorly defined or not fully comparable so that misleading or divergent results are possible. This issue is dedicated to state of the art purification and characterization methods of food allergens. A food allergen library was established, comprising known and newly identified allergens from various foods, in order to collect purified allergen material with defined and comparable quality. [source]


    Purification and characterization of natural Bet v 1 from birch pollen and related allergens from carrot and celery

    MOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 12 2007
    Mirko A. Bollen
    Abstract Birch pollen allergy is predominantly caused by the major allergen Bet v 1 and can lead to crossreactions with homologous proteins in food. Two major cross-reactive food allergens are Dau c 1 from carrot and Api g 1 from celery, which have never been purified from their natural source. Here, we describe a non-denaturing purification method for obtaining natural Bet v 1, Dau c 1 and Api g 1, comprising of ammonium sulfate precipitation, hydrophobic interaction chromatography and size exclusion chromatography. This method resulted in 98,99% pure isoform mixtures for each allergen. Characterization of these isoform mixtures with Q-TOF MS/MS clearly showed earlier reported isoforms of Bet v 1, Dau c 1 and Api g 1, but also new isoforms. The presence of secondary structure in the three purified allergens was demonstrated via circular dichroism and showed high similarity. The immune reactivity of the natural allergens was compared with recombinant proteins by Western blot and ELISA and showed similar reactivity. [source]


    IGD food labelling initiatives on food allergens and food safety

    NUTRITION BULLETIN, Issue 4 2000
    Sue Gatenby
    Summary An Institute of Grocery Distribution initiative on food labelling has recently addressed two areas of public concern , the presence of allergens in foods and general food safety. Voluntary Guidelines on Labelling, developed by cross-sector working groups in these areas, have recently been published and are briefly summarised in this paper. [source]


    Delayed- and immediate-type reactions in the atopy patch test with food allergens in young children with atopic dermatitis

    PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 1 2009
    A. C. A. Devillers
    In recent years, the atopy patch test (APT) has been suggested as an addition in the allergological work-up of children with atopic dermatitis (AD) and suspected food allergy. We initiated a prospective clinical study in children with AD younger than 3 yr, to evaluate the additional clinical value of the APT next to our own standardized allergological work-up in case of a suspected food allergy. One hundred and thirty-five children were included in the study. They were tested using the skin application food test (SAFT), the APT and measurement of specific IgE. The allergens used in the skin tests were freshly prepared food stuffs and included commercially available cow's milk (CM), the egg white of a hard boiled hen's egg and mashed peanuts in a saline solution. Allergy was defined using a flowchart incorporating the results from the SAFT, oral challenges (OCs) and elimination and (re)introduction periods. To determine the additional value of the APT next to the SAFT, we analyzed the SAFT negative patients per allergen and used an exact binary logistic analysis to evaluate the simultaneous effects of the APT and measurement of specific IgE, calculating mutually adjusted odds ratios (ORs) for positive APTs and specific IgE levels above 0.70 U/l. We found clinically relevant food allergies in 23% (egg white) to 28% (CM and peanut) of our study population. Positive SAFT reactions were observed in 14% (peanut), 16% (egg white) and 21% (CM) of our patient population. Next to the SAFT, we did not observe a significant additional value of the APT for the diagnosis of CM or egg white allergy, but we did find a significant additional value for the diagnosis of peanut allergy (OR = 11.56; p < 0.005, 2-sided). In clinical practice this statistically significant value does not exclude the need for OC and controlled elimination and (re)introduction periods due to the presence of false-negative as well as false-positive results in the APT. In conclusion, we could not find enough support for the current addition of the APT to our standardized allergological work-up in young children below the age of 3 yr with AD and suspected food allergy. At the moment the additional value of the classical delayed-type APT next to the SAFT seems to be very limited at best in this study population and does not justify the time-consuming nature of the skin test. [source]


    The importance of early complementary feeding in the development of oral tolerance: Concerns and controversies

    PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 5 2008
    Susan L. Prescott
    Rising rates of food allergies in early childhood reflect increasing failure of early immune tolerance mechanisms. There is mounting concern that the current recommended practice of delaying complementary foods until 6 months of age may increase, rather than decrease, the risk of immune disorders. Tolerance to food allergens appears to be driven by regular, early exposure to these proteins during a ,critical early window' of development. Although the timing of this window is not clear in humans, current evidence suggests that this is most likely to be between 4 and 6 months of life and that delayed exposure beyond this period may increase the risk of food allergy, coeliac disease and islet cell autoimmunity. There is also evidence that other factors such as favourable colonization and continued breastfeeding promote tolerance and have protective effects during this period when complementary feeding is initiated. This discussion paper explores the basis for concern over the current recommendation to delay complementary foods as an approach to preventing allergic disease. It will also examine the growing case for introducing complementary foods from around 4 months of age and maintaining breastfeeding during this early feeding period, for at least 6 months if possible. [source]


    Comparison of ADVIA Centaur® and Pharmacia UniCAP® tests in the diagnosis of food allergy in children with atopic dermatitis

    PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 7 2007
    Cécile Contin-Bordes
    In a study comprising 63 children diagnosed with atopic dermatitis, the results of the ADVIA Centaur system was compared with the results obtained with the Pharmacia UniCAP100 system, which has been widely considered as a reference method for seric specific IgE (sIgE) measurements. The individual immunization against the most common food allergens [egg (f1), cow milk (f2), cod (f3), wheat (f4), peanut (f13) and soy bean (f14)] was determined by in vitro serum IgE testing and skin prick test (SPT). The comparison of the sIgE titers revealed a good concordance between the Centaur and the UniCAP tests for f1, f3, and f13 (94 %, 91 %, and 96 % respectively). However, the concordance was lower for f2, f4, and f14 (76 %, 77 %, and 77 % respectively) because of discrepancies between the two techniques. When compared with SPT and clinical diagnosis, on the 40 discordant cases found between the Centaur and the UniCAP, the Centaur showed concordance with the patients food reaction and SPT in 34/40 cases, and UniCAP in only 6/40 cases. Accordingly, the Centaur test displayed a statistically significantly better performance on specificity and concordance with SPT for f2, f4, and f14 (concordance/specificity = 70%/71%, 76%/75% and 90%/88% respectively), than the CAP test (49%/54%, 51%/52% and 67%/65% respectively). [source]


    Parental knowledge and use of epinephrine auto-injector for children with food allergy

    PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 3 2006
    G. Pouessel
    Epinephrine should be prescribed for patients at risk of anaphylaxis. Our purpose was to determine the use of Anapen® prescribed for food-allergic children, to assess parental knowledge regarding Anapen, and to evaluate the arrangements for emergency kits and personalized care projects in everyday life. A prospective study was performed with a questionnaire sent to families with a food-allergic child previously prescribed Anapen. One hundred and fifty two families were contacted and finally 111 children included (median age 6.5 yrs). Main food allergens were peanuts (n = 89), egg (n = 39) and cow's milk (n = 10). The use of Anapen had been demonstrated to 90% of parents (by prescribing physician, 69%; pharmacist, 25%; general practitioner, 5%; nurse 1%), with a training device (76%) and/or written instructions (49%). When asked to list symptoms requiring injection, 48% of parents cited more than one response: breathing difficulties only (23%), or with angio-edema (41%), collapse or faintness (38%), anaphylactic shock (48%). Of 107 children attending school, 54% had a personalized care project, 72% an Anapen device, and 60% a complete emergency kit (epinephrine, inhaled , -agonist, corticosteroid, anti-H1 drug). , -Agonists were forgotten at school by 34 children (13 asthmatics). Anapen was used in one child for angio-edema and dyspnea after inadvertent ingestion of egg at home. In our population, epinephrine auto-injectors and emergency kits were insufficiently available at schools and in daily life. The use of auto-injectors was not adequately demonstrated. The prescription of epinephrine for food-allergic children at risk of anaphylaxis requires accurate diagnosis, educational programs, information, and follow up. [source]