Toll-like receptor 4 and Syk kinase shape dendritic cell-induced immune activation to major house dust mite allergens.

Background: House dust mite (HDM) is a major cause of respiratory allergic diseases. Dendritic cells (DCs) play a central role in orchestrating adaptive allergic immune responses. However, it remains unclear how DCs become activated by HDM.

IgE cross-inhibition between Ara h 1 and Ara h 2 is explained by complex formation of both major peanut allergens.

Background: Surprisingly, IgE cross-reactivity between the major peanut allergens Ara h 1, 2, and 3 has been reported despite very low sequence identities.

Objective: We investigated the unexpected cross-reactivity between peanut major allergens.

Methods: Cross-contamination of purified natural Ara h 1, 2, 3, and 6 was assessed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), Western blot test, liquid chromatography-tandem mass spectrometry (LC-MS/MS), and sandwich enzyme-linked immunosorbent assay (ELISA).

Impact of Food Matrices on Digestibility of Allergens and Poorly Allergenic Homologs.

Background: Protease resistance is considered a risk factor for allergenicity of proteins, although the correlation is low. It is nonetheless a part of the weight-of-evidence approach, proposed by Codex, for assessing the allergenicity risk of novel food proteins. Susceptibility of proteins to pepsin is commonly tested with purified protein in solution.

Peach allergen Pru p 1 content is generally low in fruit but with large variation in different varieties.

Background: Pru p 1 is a major allergen in peach and nectarine, and the different content in varieties may affect the degree of allergic reactions. This study aimed to quantify Pru p 1 levels in representative peach varieties and select hypoallergenic Pru p 1 varieties.

Methods: To obtain monoclonal and polyclonal antibodies, mice and rabbits, respectively, were immunized with recombinant Pru p 1.

Variation in IgE binding potencies of seven Artemisia species depending on content of major allergens.

Background: Artemisia weed pollen allergy is important in the northern hemisphere. While over 350 species of this genus have been recorded, there has been no full investigation into whether different species may affect the allergen diagnosis and treatment. This study aimed to evaluate the variations in amino acid sequences and the content of major allergens, and how these affect specific IgE binding capacity in representative Artemisia species.

Protease resistance of food proteins: a mixed picture for predicting allergenicity but a useful tool for assessing exposure.

Background: Susceptibility to pepsin digestion of candidate transgene products is regarded an important parameter in the weight-of-evidence approach for allergenicity risk assessment of genetically modified crops. It has been argued that protocols used for this assessment should better reflect physiological conditions encountered in representative food consumption scenarios.

Aim: To evaluate whether inclusion of more physiological conditions, such as sub-optimal and lower pepsin concentrations, in combination with pancreatin digestion, improved the performance of digestibility protocols used in characterization of protein stability.

Identification of a 62-kDa major allergen from Artemisia pollen as a putative galactose oxidase.

Background: Around 20 years ago, a 60- to 70-kDa protein was reported as a major allergen of mugwort (Artemisia vulgaris) pollen. This study was to identify and characterize its molecular properties.

Methods: Sera from 113 Chinese and 20 Dutch Artemisia-allergic/sensitized subjects (and pools thereof) were used to identify the 60- to 70-kDa allergen.

Abnormal Responses to Local Esophageal Food Allergen Injections in Adult Patients With Eosinophilic Esophagitis.

Skin tests and measurement of serum levels of immunoglobulin E do not accurately identify foods for elimination from the diets of patients with eosinophilic esophagitis (EoE). We investigated whether an esophageal prick test, in which the esophageal mucosa is challenged by local injection of allergen extracts, could identify individuals with esophageal sensitization. During endoscopy, 6 allergens were injected in the esophagus of 8 patients with EoE and 3 patients without EoE (controls).

Development of a strategy for the total chemical synthesis of an allergenic protein: the peach LTP Pru p 3.

The possibility to obtain allergenic proteins by means of total chemical synthesis would be a big step forward in the development of cures to food allergy and in the study of the mechanism of allergic reactions, because this would allow to achieve control at the molecular level over the structure of the product and to study its relationship with the allergenic activity in fine details. This is instead not possible by using allergens produced by extraction from natural sources or by recombinant DNA techniques. In this work, we aimed to test for the first time the feasibility of the total chemical synthesis of an allergenic protein.

IgE-binding potencies of three peach Pru p 1 isoforms.

Scope: Pru p 1, the Bet v 1 homologue from peach, has been identified as a clinically relevant allergen. Three isoforms have been described, two in peach fruit (Pru p 1.0101 and Pru p 1.

Allergic sensitization is associated with inadequate antioxidant responses in mice and men.

Background: Allergies arise from aberrant Th2 responses to allergens. The processes involved in the genesis of allergic sensitization remain elusive. Some allergens such as derived from house dust mites have proteolytic activity which can induce oxidative stress in vivo.

Development of a hypoallergenic recombinant parvalbumin for first-in-man subcutaneous immunotherapy of fish allergy.

Background: The FAST (food allergy-specific immunotherapy) project aims at developing safe and effective subcutaneous immunotherapy for fish allergy, using recombinant hypoallergenic carp parvalbumin, Cyp c 1.

Objectives: Preclinical characterization and good manufacturing practice (GMP) production of mutant Cyp (mCyp) c 1.

Methods: Escherichia coli-produced mCyp c 1 was purified using standard chromatographic techniques.

Oil body-associated hazelnut allergens including oleosins are underrepresented in diagnostic extracts but associated with severe symptoms.

Background: Oil body-associated allergens such as oleosins have been reported for important allergenic foods such as peanut, sesame and hazelnut. Here we investigate whether oil body associated proteins (OAPs) are linked with specific clinical phenotypes and whether they are represented in skin prick test (SPT) reagents.

Methods: A hazelnut OAP fraction was characterized by mass-spectrometry (MS) to identify its major constituents.

The prevalence and distribution of food sensitization in European adults.

Background: Complaints of 'food allergy' are increasing. Standardized surveys of IgE sensitization to foods are still uncommon and multicountry surveys are rare. We have assessed IgE sensitization to food-associated allergens in different regions of Europe using a common protocol.

Peanut-specific IgE antibodies in asymptomatic Ghanaian children possibly caused by carbohydrate determinant cross-reactivity.

Background: The prevalence of peanut allergy has increased in developed countries, but little is known about developing countries with high peanut consumption and widespread parasitic infections.

Objective: We sought to investigate peanut allergy in Ghana.

Methods: In a cross-sectional survey among Ghanaian schoolchildren (n = 1604), data were collected on reported adverse reactions to peanut, peanut sensitization (serum specific IgE and skin reactivity), consumption patterns, and parasitic infections.

Lentil (Lens culinaris) lipid transfer protein Len c 3: a novel legume allergen.

Background: Lentils are increasingly consumed in many parts of the world.Two allergens, Len c 1 and 2, have been reported previously. Recently, peanut and green bean lipid transfer proteins (LTPs) have been identified as the first two members of an important group of allergens that might be associated with severe food allergies.

The purification and characterisation of allergenic hazelnut seed proteins.

A lipid transfer protein (LTP, Cor a 8) together with the 11S (Cor a 9) and 7S seed storage globulins (Cor a 11) are major food allergens present in hazelnut. Methods are described for their purification and characterisation using in-gel tryptic digestion mass spectrometry to confirm their identities and circular dichroism and Fourier-transform infrared spectroscopies to demonstrate that they are authentically folded. Preliminary immunochemical studies have also confirmed that the purified preparations retain their immunological properties in terms of immunoglobulin E binding, determined by immunoblotting using serum from hazelnut allergic patients.

Purification and characterisation of a panel of peanut allergens suitable for use in allergy diagnosis.

Peanut is a major cause of type 1 hypersensitive reactions including anaphylaxis. This results from the presence of a number of protein allergens, six of which are being studied as part of the EU FP6 EuroPrevall programme. These are Ara h 1 (7S globulin), Ara h 2, Ara h 6 (2S albumins), Ara h 3/4 (11S globulins) and Ara h 8 (Bet v 1 homologue).

Hazelnut allergy: from pollen-associated mild allergy to severe anaphylactic reactions.

Purpose Of Review: Hazelnut allergy can vary between mild oral symptoms and potentially dangerous anaphylaxis. There is a need to predict which subjects are at risk for severe reactions. In this study, possibilities for 'component-resolved diagnosis', based on sensitization to different allergens in hazelnut, are discussed.