Flour Allergens Research Articles

Occupational Asthma in the Food Industry

Inhalation of food-derived allergens during food processing at the workplace represents a risk for developing occupational asthma (OA) in exposed workers. Cereal flours and seafood are the causal agents most frequently involved. The management of food-derived OA includes timely pharmacologic therapy and environmental interventions aimed to avoid or reduce exposure to the offending agent to increase the probability of recovery. Cessation of exposure is the best option, but when the causative agent cannot be completely avoided reduction of exposure, through modification of food processing, improving ventilation, mechanization, etc. can be considered as an alternative. Quantification of real exposure levels is crucial, and new accurate immunologic and chemical assays able to detect low levels of aerosolized flour and seafood allergens have recently been developed. Recent papers have described intervention strategies effective in reducing airborne allergen exposure in flour and seafood industry, but the long-term health impact of this intervention has still to be defined. Specific allergen immunotherapy (SIT) might be another management option in individuals with IgE-mediated food-induced OA. Both a short- and a long-lasting beneficial effect of SIT with wheat flour in reducing symptoms whilst keeping the patient at work has been shown in bakers’ asthma, but at present, SIT is not for routine use for bakers’ asthma due to the lack of commercial standardized extracts. A better identification on a molecular basis of allergens involved in flour and in other IgE-mediated food-derived OA might help in preparing new extracts suitable for immunotherapy. In selected cases of bakers’ asthma, the monoclonal antibody omalizumab has been effective in reducing symptoms. SIT and omalizumab might represent further management options in IgE-mediated OA in food industry.

Should wheat, barley, rye, and/or gluten be avoided in a 6-food elimination diet?

Eosinophilic esophagitis (EoE), a food antigen-mediated disease, is effectively treated with the dietary elimination of 6 foods commonly associated with food allergies (milk, wheat, egg, soy, tree nuts/peanuts, and fish/shellfish). Because wheat shares homologous proteins (including gluten) with barley and rye and can also be processed with these grains, some clinicians have suggested that barley and rye might also trigger EoE as a result of cross-reaction and/or cross-contamination with wheat. In this article, we discuss the theoretical risks of cross-reactivity and cross-contamination among wheat, barley, and rye proteins (including gluten); assess common practices at EoE treatment centers; and provide recommendations for dietary treatment and future studies of EoE.

Diagnostic value of the lymphocyte transformation test for non‐IgE mediated food allergy

The aim of our study was to verify the diagnostic value of lymphocyte transformation test (LTT) for non-IgE mediated food allergy. We investigated 3 groups of patients for identifying the food hypersensitivity. 1. Group - 60 patients with symptoms of irritable bowel syndrome (IBS) without a diagnosis of organic gastrointestinal disease. 2. Group - 19 patients with atopic dermatitis, polysenzitization to inhalant, not to food allergens. 3. Group - 6 infants (3-12 months old) with intestinal symptoms (bloody stool and abdominal distention) and positive elimination diet with cow's milk. Control group -10 healthy non-atopic patients. We performed skin prick test (SPT) and the flow-cytometric basophil activation test(BAT) with commercial extracts of wheat, rye flour, egg, milk and soy allergens Alyostal (Stallergenes) in all patients. Serum levels of milk, casein, wheat, rye flour, egg and soy specific IgE were measured by Immulite. The lymphocyte transformation test was performed with the same food allergens. Open food challenge test (OFC) was completed after 14 days of elimination diet. All patients had negative SPT, sIgE and BAT with milk, casein, wheat, rye, egg and soy allergens. They had negative celiac disease serology. In 1.group 42 patients (70%) had positive LTT for wheat flour, none of them for other allergens. Open food challenge test by ingestion of daily serving cooked wheat pasta were positive in all 42 positive patients. 18 patients (30%) had negative LTT for all allergens. In 2.group 15 patients had positive LTT for wheat flour, 2 for milk, 1 for soy allergens Elimination diet of wheat or milk or soy improved eczematic manifestations. In 3.group all 6 infants had positive LTT to cow/s milk and casein allergens. They had positive OFC test with cow/s milk after elimination diet. Patients of control group were negative in all vitro tests. In our study the lymphocyte transformation test were useful diagnostic tools for non-IgE mediated food allergy.

Effectiveness of interventions to reduce flour dust exposures in supermarket bakeries in South Africa

RationaleA recent study of supermarket bakery workers in South Africa demonstrated that 25% of workers were sensitised to flour allergens and 13% had baker's asthma. Evidence on exposure reduction strategies...

Allelic Variation of Wheat Flour Allergens in a Collection of Wheat Genotypes

Wheat is the most widely grown crop in the world and provides 20% of the daily protein and food calories for 4.5 billion people. Together with rice, it is the most important food crop in the developing world. In the last decades, various symptoms have been recorded across the population due to the consumption of wheat products, also summarized as “wheat allergy.” Wheat allergy is usually reported as a food allergy but can also be a contact allergy as a result of exposure to wheat. Several important wheat allergens have been characterized in the last years through biochemical, immunological, and molecular biological techniques. In the present work, the identification of allelic variation of genes involved in wheat allergy was reported. A collection of wheat genotypes was screened in order to identify new alleles. A total of 14 new alleles were identified forprofilin, triosephosphate-isomerase, dehydrin, glyceraldehyde-3-phosphate-dehydrogenase,α/βgliadin, GluB3-23,andGlutathione transferaseallergen genes (located on chromosomes 1B, 3B, 6A, and homoelogous groups 5 and 7), potentially related to a minor allergenicity and useful in breeding programs.

From GISR 2012: present status and future perspectives of Raman researches in Italy

From GISR 2012: present status and future perspectives of Raman researches in Italy

The IgE repertoire in patients with food allergy resolved at component level

Background Currently, more than 1200 purified allergens with defined structures are available. Some of them are used for food allergy diagnostics. We aimed to assess individual patientssensitizationtization profiles of food allergens by means of component resolved diagnosis. Methods Serum samples were analysed by microarray Immuno CAP ISAC (Phadia), which allows to detect specific IgE against more than 100 of molecular components. We have retrospectively analyzed 153 patients with proven food allergy, 96 of them being children under 18 years. We recorded occurence of early reactions including OAS and anaphylaxis and also delayed reactions (atopic eczema and eosinophilic gastrointestinal diseases). IgE antibodies against individual food alergens were divided to groups based on their origin and affiliation to any of panalergen families. With this approach, antibodies against ten groups of alergens were analyzed in indivi- dual age categories and diagnostic groups: cow' sm ilk allergens, hen's egg allergens, parvalbumins, lipid trans- fer proteins, flour allergens including gluten, vicilins, conglutins, cupin family allergens, 2S albumins and PR- 10 family proteins. Results As expected, in patients below age of 3 years, allergens to mild and egg occured most frequently. Suprisingly, however, we detected more than 40% of patients being sensitization against seed storage proteins (2 s albumins) and almost 30 % of patients have been sensitized by alergens of PR-10 group. In children allergic to peanut sensitization to proanafylactis alergens (Arah h 1, 2, 3) prevailed. In contrary, in older patients over 18 years we have found mainly sensitization to Ara h 8 from Bet v 1 family homologous proteins. Patients with eosinophilic gastrointestinal diseases, mainly eosinophilic esophagitis, demonstrated sensitization to Bet v 1 homologous pro- teins in more than 50% and almost 30% sensitization to allergens from seed storage protein families. Approxi- mately 20% of our patients had detectable antibodies against one or more of lipid transfer proteins. Conclusion CRD using microarray technics enables to detect IgE sen- sitisation profile not only in one patient, but also in a group of patients with defined age and diagnosis. This fact could contribute to optimalisation of diet according to possible cross-reactivity. Sensitization to proanaphylactic alergens, like LTPs and seed storage proteins, enables to detect individual risk of food induced anaphylaxis.

Variability of allergenicity within 29 genotypes including some genetically modified genotypes

Background Breeding of cereals has been particularly active in the last hundred years, resulting in spectacular improvements in agronomic, resistance or technological traits. Unfortu- nately for predisposed consumers wheat may induce aller- genicity either food or respiratory. More recently, the genetic modification (GM) technology for crop improve- ment has emerged and although GM wheats are not culti- vated at the moment, it is not excluded that they are being produced. In the frame of GM evaluation and according to the codex Alimentarius, the allergenicity has to be evaluated. The studied genotypes belong to the two main wheat cul- tivated species, T. aestivum and T. Durum. In this study, IgE were collected from patients suffering from food or respiratory allergy and used as probes to detect wheat flour allergens in an ELISA assay. Data were analysed using paired samples t-test and two-way ANOVA. In order to increase the sensibility the salt soluble proteins fraction was separated into two fractions, metabolic and chloroform-methanol soluble (CM), their protein compo- sition was analysed and their IgE reactivity controlled. Results Both fractions were IgE reactive and the CM-like fraction was enriched in alpha amylase inhibitors and LTP. Two factors were studied, genotype and serum, both have a significant effect on the IgE-binding capacity. The compar- ison of means revealed significant differences in the IgE concentration for 3 GM lines versus their wild type what- ever the fraction considered. However, it was noticeable that significant differences were also detected between cultivars. The reactivity of the T. durum cultivars were in the range of 28-50 ng/ml and 40-70 ng/ml for the metabolic and CM_like fractions respectively. That of GM lines, even those that were significantly different from their wild type lines, were included in these reactivity ranges. Similar results were obtained for T. aestivum cultivars. Conclusion This study drives us to conclude that the transformation impacts the allergenicity, by increasing or decreasing it. The level of allergenicity measured for the GM lines was always lower that the higher value measured for the cultivated genotypes tested.

Sensitisation to cereal flour allergens is a major determinant of elevated exhaled nitric oxide in bakers

ObjectiveVarious studies of the usefulness of fractional exhaled nitric oxide (FeNO) in occupational settings remain inconclusive. The objective was to investigate the determinants of increased FeNO in bakery workers.MethodsA cross-sectional...

Environmental and occupational respiratory diseases - 1054: Sensitization to storage mites, wheat and yeast allergens in Cuban bakers

This article was originally published online on 23 April 2013 For many years, bakers have been considered a professional group at risk of developing allergic diseases by factors related to the work environment. In our country, in this employment sector, the frequency of allergic sensitization to dust mites, wheat flour, soy and yeast is not known. This study aimed at assessing the frequency of work-related symptoms and sensitivity to mites and other occupational allergens among bakery workers through skin prick test (SPT). A no-matched case-controlled study was performed. The study group included 17 bakery workers in Havana, Cuba, median age 33 (range 18- 55 years old), and the control group comprised 14 non-exposed subjects, median age: 28 (range 22-47 years old). Both groups had male predominance. A medical resume and SPT were performed to all subjects. Of 17 bakery workers, eight had one or more work-related symptoms and the respiratory symptoms were the most reported. The higher sensitization frequency in bakers corresponded to yeast (88.2 %), followed by storage and house dust mites, A. siro and Dermatophagoides siboney (a Caribbean species similar to D. farinae) and wheat with 82.3% each one. The least sensitization value was found to D. pteronyssinus (only 47 %), in contrast to the response pattern found in the control group where this mite was the predominant sensitizing allergen. The largest wheal diameters were found to A. siro and T. putrescientae in the bakers group and to D. farinae and B. tropicalis in the control group. There is a high sensitivity to storage mites and wheat flour and yeast allergens among bakery workers, which can be an important risk factor to consider for their occupational safety.

Evaluation of immunore activity of wheat bread made from fermented wheat flour

Combined culture of lactic acid bacteria (Lactobacillus brevis, L. plantarum i L. sanfranciscencis) and baker’s yeasts was used in order to reduce immunoreactivity of gluten from wheat. Flour and dough samples were analysed in terms of lactic acid fermentation and thermal processing. Their immunoreactivity was determined with ELISA method using both anti-gliadin antibodies from patients suffering from coeliac disease and rabbit anti-QQQPP peptide (main epitope of flour allergen) antibodies. Also, immunoreactivity was measured in the final products after simulated digestion. The obtained total effectiveness of the fermentation and digestion processes amounted to less than 30% relative to immunoreactivity of human anti-gliadin antibodies and less than 10% relative to immunoreactivity of anti-QQQPP peptide antibodies as compared to the baking made with non-fermented flour.  

The ‘take home’ burden of workplace sensitizers: Flour contamination in bakers' families

BackgroundExposure to flour/flour constituents is a leading cause of occupational asthma. Paternal occupational exposure to flour has been associated with increased likelihood of childhood asthma, raising the possibility of para-occupational exposure whereby family members are exposed to sensitizers ‘taken home’ on contaminated skin/clothing. ObjectiveTo establish whether workplace contamination of skin/clothing with wheat flour allergen (WFA) and fungal α-amylase (FAA) is associated with increased levels of these allergens in bakers' homes. MethodsBakeries in north-east Scotland were invited to participate. Control subjects were recruited from University of Aberdeen staff and students. Exposure assessment was carried out in bakeries, bakers' cars and the homes of bakers and controls using surface wipe and vacuum sampling; samples were analyzed for total protein, FAA and WFA. Results164 wipe samples and 49 vacuum samples were collected from 38 bakers (from 5 bakeries) and 10 controls.Compared to non-bakers, bakers had higher median levels of WFA and FAA in house vacuum samples; the difference was statistically significant for WFA/total protein (515.8×10−6 vs. 163.7×10−6, p=0.031), FAA/total protein ratios (1.45×10−6 vs. 0.04×10−6, p<0.001) and FAA loading (median 1.2pg/cm2 vs. 0.1pg/cm2, p<0.001) with workplace exposure–home contamination relationships between bakers with higher and lower workplace contamination.We found positive correlations between WFA contamination of the bakers' foreheads and cars (rs0.57, p=0.028), foreheads and houses (rs0.46, p=0.025), shoes and houses (rs0.45, p=0.029); and between FAA contamination of shoes and houses (rs0.46, p=0.023), and cars and houses (rs0.70, p=0.008). There was no evidence of bakers using work-sourced flour for domestic baking. ConclusionsThis work demonstrates pathways for ‘take home’ exposure of occupationally sourced flour. Taken with our previous work, showing that bakers' children are more likely to have asthma, this supports the need for further investigation to establish whether ‘take home’ of occupationally sourced flour is widespread with health consequences.

A comparative study of different bio-processing methods for reduction in wheat flour allergens

Gliadin and glutenins comprising the prolamins of gluten present in wheat flour are well recognized for allergic properties. There are four kinds of symptoms of adverse reactions to wheat flour: celiac disease, Baker’s asthma, atopic dermatitis and food-dependent-exercise-induced anaphylaxis. Studies have shown that wheat flour becomes hypoallergenic by hydrolyzing peptide bonds near the essential proline residues of the epitope structure. Present study was framed with the main objective to develop modified gluten flours by various bio-processing methods and to study their rheological, biochemical and immunological characteristics. T. durum semolina was incubated with proteolytic enzymes such as pepsin, pancreatin and protease for 4, 6, 8, 10 h and overnight. Similarly, the semolina flour was treated thermally using microwave heating at different wavelength such as 360, 540, 720, 960 W. Apart from this, non-gluten blend was prepared by blending semolina with 40% of non-gluten flours. The resultant samples were subjected to different biochemical and immunochemical studies. Microstructure and Rheological characteristics are also studied. Results revealed affected microstructure of gluten matrix and rheological properties of the microwave- and enzyme-treated flour. The electrophoresis pattern of pepsin-treated flour showed decrease in the intensity of protein bands corresponding to allergen profile than control. The flour treated with protease also showed distinct bands than control. The electrophoresis pattern of non-gluten blends also showed decrease in the intensity of the bands corresponding to allergens. Immunochemical studies confirm the use of proteolytic enzymes is efficient method for reducing wheat allergens.

Milk and wheat allergy, and celiac disease

Cow's milk, egg, wheat, soy, peanut, and fish account for about 90% of the food allergies but there are considerable differences from one country to another. Milk allergy is among the best characterized food allergies, particularly in infants and small children. Only part of the children with early allergy to cow's milk grow into shool-age with milk allergy but those that do often have severe symptoms and high specific IgE level to milk. In accordance, attaining tolerance to cow's milk is associated with decreased epitope binding by IgE and a concurrent increase in corresponding epitope binding by IgG4. Recent data point that analysis of IgE response to milk components may help in determining those with higher risk for persistent or more severe milk allergy. Among wheat allergic patients, co-sensitization to cow's milk and hen's egg is common. Wheat ingestion may trigger immunoglobulin E (IgE)-mediated immediate symptoms, including urticaria, angioedema, bronchial obstruction, nausea and abdominal pain, or in severe cases, even systemic anaphylaxis. Delayed reactions include gastrointestinal symptoms and worsen-ing of atopic dermatitis. In addition to food allergy, wheat ingestion may cause exercise-induced anaphylaxis, or celiac disease (CD), and inhalation and handling of wheat flour aller-gens may lead to respiratory allergy, or contact urticaria on the skin. Wheat IgE is commonly found in all ages of atopic children when whole grains are used as an antigen either in skin prick tests or serum IgE measurements. The specificity of this IgE re-sponse in identifying clinical disease, however, is poor. It is of importance to recognize dis-ease-determining components in the IgE response. Several studies have shown that sensiti-zation particularly to omega-5 gliadin is associated with challenge-proven wheat-allergy. Moreover, recent data imply that gliadin-positive patients have more likely severe reactions after wheat ingestion. A well-characterized severe clinical entity is also wheat-dependent, ex-ercise-induced anaphylaxis in which sensitization to omega-5 gliadin is a prerequisite. We have analyzed especially the gliadin-sepcific responses in wheat allergy. Sensitization to gliadin with a SPT wheal of ≥5 mm at the time of the diagnostic challenge was associated with a slower course of recovery from wheat hypersensitivity (p = 0.019), and a SPT wheal of ≥ 3 mm to gliadin at any time was associated with the development of asthma. Recently, we examined IgE response to 22 wheat components in children with challenge positive wheat allergy and their controls. The results show that wheat-allergy diagnosis can be improved considerably by component-based ap-proach. In the future, wheat IgE diagnosis should include at least measurement of IgE to gli-adins. Gluten and its major component, gliadin, is essential also in the pathogenesis of celiac dis-ease. Gliadin can be a target of both cellular and humoral immune responses. Approximately 90 percent of patients with celiac disease have the HLA-DQ2 haplotype, explaining the family-association of the disease but still leaving open the wide variability in prevalence between dif-ferent Caucasian populations. Both IgA and IgG antibodies can be seen in CD patients but the most sensitive diagnostic work-up is to define tissue transglutaminase (tTG) transglutami-nase IgA antibodies.

A new approach to the isolation and characterization of wheat flour allergens

The incidence of food allergy to wheat is increasing. Its diagnosis depends on the purity of major allergens and their inclusion in tests. Isolation and characterization of wheat allergens are therefore of utmost importance. To purify and identify wheat flour allergens most frequently recognized by patients' IgE antibodies and to study their allergenicity. Water/salt-soluble extracts from wheat flour were prepared and separated using a combination of ultrafiltration, isoelectric focusing and liquid chromatography. Purified proteins were analysed by immunoblotting using pooled sera from patients with atopic dermatitis who possessed IgE specific to wheat. Wheat proteins found to bind IgE were subsequently identified by matrix-assisted laser desorption/ionisation-time of flight mass spectrometry. The frequency and intensity of IgE binding of isolated proteins were tested using individual sera from patients and controls. We developed a procedure that allows isolation of wheat allergens from natural sources. Twenty-seven potential wheat allergens have been successfully identified; of these, the following seven are newly reported in food allergy: endogenous α-amylase/subtilisin inhibitor, trypsin/α-amylase inhibitor (AAI) CMX1/CMX3, thaumatin-like protein (TLP), xylanase inhibitor protein-1, β-glucosidase, class II chitinase and 26 kDa endochitinase. TLP and wheatwin were shown to activate patients' basophils to a similar extent as two well-known allergens, lipid transfer protein (Tri a 14) and AAI 0.19 (Tri a 28.0101). Our new approach enables the isolation of water/salt-soluble wheat allergens in their native form in amounts sufficient both for biological testing (in vivo and in vitro) and for physicochemical characterization. Such studies will lead to a more detailed knowledge of allergenicity of wheat proteins and to improved accuracy of diagnostic tests.

Multiple wheat flour allergens and cross-reactive carbohydrate determinants bind IgE in baker’s asthma

Several wheat flour allergens relevant to baker's asthma have been identified in the last 25 years. The aim of this study was to determine the frequency of sensitization to these allergens in German bakers. Using recombinant DNA technology, the following wheat flour allergens were cloned, expressed in Escherichia coli and purified: five subunits of the wheat α-amylase inhibitors (WTAI-CM1, WTAI-CM2, WTAI-CM3, WDAI-0.19 and WMAI-0.28), thioredoxin, thiol reductase or 1-cys-peroxiredoxin homologues, triosephosphate-isomerase, αβ-gliadin, serpin, glyceraldehyde-3-phosphate-dehydrogenase, a nonspecific lipid transfer protein (nsLTP), dehydrin, profilin and peroxidase. In addition, ImmunoCAPs with the recombinant allergen ω-5-gliadin and two cross-reactive carbohydrate determinants (CCDs), horse radish peroxidase (HRP) and the N-glycan of bromelain (MUXF), were used. Specific IgE was measured in wheat flour-positive sera from 40 German bakers with work-related asthma/rhinitis and 10 controls with pollinosis. Thirty bakers (75%) had IgE to at least one of the 19 single allergens. Most frequent was IgE to WDAI-0.19, HRP and MUXF (25% each), followed by WTAI-CM1 (20%), thiol reductase (16%), WTAI-CM3 (15%), WTAI-CM2 and thioredoxin (12.5%), WMAI-28, triosephosphate-isomerase, αβ-gliadin (10%), 1-cys-peroxiredoxin (7.5%), dehydrin, serpin, glyceraldehyde-3-phosphate-dehydrogenase (5%), ω-5-gliadin, nsLTP and profilin (2.5%). Fifteen bakers (38%) had IgE to any α-amylase inhibitor and 12 (30%) to at least one CCD. The controls reacted exclusively to CCDs (80%), profilin (60%), thioredoxin (30%), triosephosphate isomerase and nsLTP (10%). The single allergen sensitization profiles obtained with 17 recombinant wheat flour allergens and two CCDs revealed no major allergen for German bakers. The highest frequencies were found for α-amylase inhibitors and CCDs.

Allergic asthma after flour inhalation in subjects without occupational exposure to flours: an experimental pilot study

Cross-reactivity between grass pollen and grain flour allergens is well known, but their significance in apprentice bakers with primary sensitization to grass pollen is not known. Twenty-five subjects with mild asthma (most of them with hay fever), but without prior occupational flour exposure, underwent standardized experimental inhalation challenges with placebo and wheat and rye flours in randomized order on three consecutive days. Sensitization to flours and environmental allergens was assessed by skin prick tests and specific IgE antibodies in sera. IgE inhibition experiments were performed with wheat and rye flours as solid phases, and grass and tree pollen as inhibitors. Five subjects experienced a positive reaction after flour inhalation (responders), whereas 20 subjects did not show such a reaction (non-responders). All responders showed sensitizations to flours, whereas only 25% of the non-responders demonstrated the same sensitization. Specific IgE concentrations to flours, but also to grass and tree pollen, were higher in responders. Inhibition experiments demonstrated cross-reactivity between flours and grass or tree pollen, with higher inhibition rates in responders. Subjects with pronounced sensitizations to grass or tree pollen, but without prior occupational exposure to flours, may experience both sensitization and allergic asthmatic reactions to flours due to cross-reactive grass and tree pollen allergens.

Molecular Characterization of Major Allergens Associated with Baker's Asthma in Wheat Flour

Many allergens belong to the defense response proteins, which are produced when the plant is under various stresses. The amino acid sequences of the main wheat flour allergens associated with baker's asthma were analyzed in this study. The gene sequences of monomeric (WMAI), dimeric (WDAI), tetrameric (WTAI, which contains 1 WTAI-CM2 unit, 2 CM3 units and 1 CM16 unit) α-amylase inhibitor and fructose bisphosphate aldolase from wheat, barley and rye were obtained and characterized. Compared with other main allergens, it was shown that the fifteen proteins have a common conserved cysteine skeleton and the presence of CC and CX1-4C motifs, which are not usually found in other non-allergenic proteins. Most of these allergens have putative N-glycosylation sites. Protein structure either mediated through di-sulfide bonds or through higher order protein-protein interactions, plays a critical role in the allergenicity of allergens. It was also found that the same protein family allergens did not share similar 3D structures. With regard to the characterized sequences as well as protein structures of allergens, it is obvious that the flour proteins that have been implicated as important wheat seed allergens causing baker's asthma are complex but have some specific related behavioral traits.

Micro‐arrayed wheat seed and grass pollen allergens for component‐resolved diagnosis

Wheat is a potent allergen source and can cause baker's asthma, food and pollen allergy. The aim of the study was to develop an allergen micro-array for differential diagnosis of baker's asthma, wheat-induced food allergy and grass pollen allergy. We analysed the immunoglobulin-E reactivity profiles of patients suffering from baker's asthma, wheat-induced food allergy and grass pollen allergy to micro-arrayed recombinant wheat flour allergens and grass pollen allergens and compared these results with clinical results and diagnostic tests based on crude wheat flour, wheat pollen and grass pollen allergen extracts. We identified recombinant wheat flour allergens, which are specifically recognized by patients suffering from baker's asthma, but not from patients with food allergy to wheat or pollen allergy. rPhl p 1 and rPhl p 5 were identified as marker allergens specific for grass pollen allergy. They can be used to replace grass pollen extracts for allergy diagnosis and to identify grass pollen allergic patients among patients suffering from baker's asthma and wheat-induced food allergy. Profilin was identified as a cross-reactive allergen recognized by patients suffering from baker's asthma, food and pollen allergy. Our results indicate that it will be possible to design serological tests based on micro-arrayed recombinant wheat seed and grass pollen allergens for the discrimination of baker's asthma, wheat-induced food allergy and grass pollen allergy.

Rhinitis guidelines and implications for occupational rhinitis

To review the most recent rhinitis guidelines in the aspects pertaining the link between rhinitis and work, and to summarize the specific literature on occupational rhinitis published in 2007 and 2008. Recently there has been a growing scientific interest in work-related rhinitis. Health personnel, cleaners, bakers, apprentices in high-risk occupations, and workers exposed to multiple agents are at increased risk of rhinitis, especially in the very first years of employment. Flour allergens are often involved and may induce nonallergic and enhance allergic airway inflammation. The specific nasal challenge remains the gold standard for diagnosis. Acoustic rhinometry and nasal lavage are validated tools for monitoring nasal response. Occupational rhinitis seems to have an impact on quality of life of affected workers and allergic rhinitis impairs work productivity. This review updated recent findings on epidemiology, mechanisms, diagnosis, management, and prevention of occupational rhinitis. This article also provides new information on the impact of occupational rhinitis on quality of life and on the impact of rhinitis on work productivity. Occupational rhinitis should be considered in daily clinical practice and research.