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).

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.

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.

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.

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.

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.

Lipid transfer protein-linked hazelnut allergy in children from a non-Mediterranean birch-endemic area.

Background: Hazelnut allergy in birch pollen-exposed areas is usually due to cross-reactivity (Cor a 1 and 2) and is usually mild in nature (oral allergy). In areas without birches, severe reactions are more prevalent and linked to sensitization to the lipid transfer protein (LTP) Cor a 8.

Objective: We sought to investigate whether sensitization to LTP plays a role in more severe (objective) hazelnut-induced symptoms in children from a birch-endemic area.

Cloning of oleosin, a putative new hazelnut allergen, using a hazelnut cDNA library.

The clinical presentation of non-pollen related allergy to hazelnut can be severe and systemic. So far, only a limited number of non-pollen related hazelnut allergens have been identified and characterized. The aim of this study was to identify and clone new hazelnut allergens.

IgE binding to pepsin-digested food extracts.

Background: Pepsin resistance of allergens like lipid transfer protein and 2S albumin has been suggested as explanation for the severity of symptoms often induced by these allergens. Component-resolved diagnosis with purified labile and stable allergens has therefore been proposed to better characterize the risk involved in a positive in vitro IgE test. However, for many foods, purified allergens are not (yet) available.

Lipid transfer proteins from fruit: cloning, expression and quantification.

Background: Lipid transfer proteins (LTP) are stable, potentially life-threatening allergens in fruits and many other vegetable foods. The aim of this study was to clone and express recombinant apple LTP (Mal d 3), as has previously been done for peach LTP (Pru p 3) and set up quantitative tests for measuring fruit LTPs.

Methods: cDNA for Mal d 3 and Pru p 3 was cloned, expressed in the yeast Pichia pastoris and the resulting proteins were purified via cation exchange chromatography.

A novel approach for the detection of potentially hazardous pepsin stable hazelnut proteins as contaminants in chocolate-based food.

Contamination of food products with pepsin resistant allergens is generally believed to be a serious threat to patients with severe food allergy. A sandwich type enzyme-linked immunosorbent assay (ELISA) was developed to measure pepsin resistant hazelnut protein in food products. Capturing and detecting rabbit antibodies were raised against pepsin-digested hazelnut and untreated hazelnut protein, respectively.

In vitro and in vivo characterization of hazelnut skin prick test extracts.

Rationale: Hazelnut allergy ranks among the most frequently observed food allergies. Clinical symptoms range from the oral allergy syndrome to life threatening anaphylaxis. Diagnosis of hazelnut allergy partially relies on in vivo testing by means of skin prick testing (SPT).

How accurate and safe is the diagnosis of hazelnut allergy by means of commercial skin prick test reagents?

Background: Allergy to tree nuts, like hazelnuts, ranks among the most frequently observed food allergies. These allergies can start at early childhood and are, in contrast to other food allergies, not always outgrown by the patient. Tree nut allergy is frequently associated with severe reactions.

IgE to Bet v 1 and profilin: cross-reactivity patterns and clinical relevance.

Background: Individuals with pollen allergy often have IgE against plant-derived foods. This can be due to cross-reactive IgE against Bet v 1 and homologues, profilins, and/or cross-reactive carbohydrate determinants.

Objective: The aim of this study was to correlate sensitization to Bet v 1 and profilin with individual recognition patterns to plant foods and clinical relevance.