Predicting the allergenicity of legume proteins using a PBMC gene expression assay.

Background: Food proteins differ in their allergenic potential. Currently, there is no predictive and validated bio-assay to evaluate the allergenicity of novel food proteins. The objective of this study was to investigate the potential of a human peripheral blood mononuclear cell (PBMC) gene expression assay to identify biomarkers to predict the allergenicity of legume proteins.

Allergenicity prediction of novel and modified proteins: Not a mission impossible! Development of a Random Forest allergenicity prediction model.

Alternative and sustainable protein sources (e.g., algae, duckweed, insects) are required to produce (future) foods.

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.

Variation in Seed Allergen Content From Three Varieties of Soybean Cultivated in Nine Different Locations in Iowa, Illinois, and Indiana.

Soybean () is an important food stock, and also considered an allergenic food with at least eight well characterized allergens. However, it is a less prevalent allergen source than many other foods and is rarely life-threatening. Soybean is incorporated into commonly consumed foods, and therefore, the allergens pose a potential concern for individuals already sensitized.

Bioinformatic screening and detection of allergen cross-reactive IgE-binding epitopes.

Protein allergens can be related by cross-reactivity. Allergens that share relevant sequence can cross-react, those lacking sufficient similarity in their IgE antibody-binding epitopes do not cross-react. Cross-reactivity is based on shared epitopes that is based on shared sequence and higher level structure (charge and shape).

Inter-laboratory optimization of protein extraction, separation, and fluorescent detection of endogenous rice allergens.

In rice, several allergens have been identified such as the non-specific lipid transfer protein-1, the α-amylase/trypsin-inhibitors, the α-globulin, the 33 kDa glyoxalase I (Gly I), the 52-63 kDa globulin, and the granule-bound starch synthetase. The goal of the present study was to define optimal rice extraction and detection methods that would allow a sensitive and reproducible measure of several classes of known rice allergens. In a three-laboratory ring-trial experiment, several protein extraction methods were first compared and analyzed by 1D multiplexed SDS-PAGE.

Assessment of potential adjuvanticity of Cry proteins.

Genetically modified (GM) crops have achieved success in the marketplace and their benefits extend beyond the overall increase in harvest yields to include lowered use of insecticides and decreased carbon dioxide emissions. The most widely grown GM crops contain gene/s for targeted insect protection, herbicide tolerance, or both. Plant expression of Bacillus thuringiensis (Bt) crystal (Cry) insecticidal proteins have been the primary way to impart insect resistance in GM crops.

[Agricultural biotechnology safety assessment].

Genetically modified (GM) crops were first introduced to farmers in 1995 with the intent to provide better crop yield and meet the increasing demand for food and feed. GM crops have evolved to include a thorough safety evaluation for their use in human food and animal feed. Safety considerations begin at the level of DNA whereby the inserted GM DNA is evaluated for its content, position and stability once placed into the crop genome.

Development of an isoform-specific tandem mass spectrometry assay for absolute quantitation of maize lipid transfer proteins.

Precise and accurate quantitation of maize grain allergens is important for seed and food industries. The major allergen in maize grain is Zea m 14, a lipid transfer protein (LTP). The B73 maize genome encodes for at least six LTPs sharing 15%-87% sequence identity to Zea m 14.

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

The measurement of endogenous allergens is required by the European Commission (EC) as part of the compositional analysis for GM products from host plants that are common causes of food allergy, such as soybean (EC Implementing Regulation No. 503/2013). In each case, the EC Implementing Regulation indicates that analysis be conducted on identified allergens as specified in the Organization of Economic Cooperation and Development (OECD) consensus documents on compositional considerations for new plant varieties.

Allergic sensitization: food- and protein-related factors.

Presented here are emerging capabilities to precisely measure endogenous allergens in soybean and maize, consideration of food matrices on allergens, and proteolytic activity of allergens. Also examined are observations of global allergy surveys and the prevalence of food allergy across different locales. Allergenic potential is considered in the context of how allergens can be characterized for their biochemical features and the potential for proteins to initiate a specific immune response.

Sensitizing properties of proteins: executive summary.

The scope of allergy risk is diverse considering the myriad ways in which protein allergenicity is affected by physiochemical characteristics of proteins. The complexity created by the matrices of foods and the variability of the human immune system add additional challenges to understanding the relationship between sensitization potential and allergy disease. To address these and other issues, an April 2012 international symposium was held in Prague, Czech Republic, to review and discuss the state-of-the-science of sensitizing properties of protein allergens.

MS(E) based multiplex protein analysis quantified important allergenic proteins and detected relevant peptides carrying known epitopes in wheat grain extracts.

The amount of clinically relevant, allergy-related proteins in wheat grain is still largely unknown. The application of proteomics may create a platform not only for identification and characterization, but also for quantitation of these proteins. The aim of this study was to evaluate the data-independent quantitative mass spectrometry (MS(E)) approach in combination with 76 wheat allergenic sequences downloaded from the AllergenOnline database ( www.

Characterization of the allergenic potential of proteins: an assessment of the kiwifruit allergen actinidin.

Assessment of the potential allergenicity (IgE-inducing properties) of novel proteins is an important challenge in the overall safety assessment of foods. Resistance to digestion with pepsin is commonly measured to characterize allergenicity, although the association is not absolute. We have previously shown that specific IgE antibody production induced by systemic [intraperitoneal (i.

The MS(E)-proteomic analysis of gliadins and glutenins in wheat grain identifies and quantifies proteins associated with celiac disease and baker's asthma.

Precise content of gliadin (Glia) and glutenin (Glu) proteins in wheat grain are largely unknown despite their association with celiac disease, various allergies, and physical processing properties of wheat. Developing methods to quantitatively measure clinically relevant proteins could support advancement in understanding exposure thresholds and clinical study design. The aim of this study was to use a data-independent mass spectrometry (MS(E)) approach for quantifying gliadin and glutenin proteins in wheat grain.

Heat stability, its measurement, and its lack of utility in the assessment of the potential allergenicity of novel proteins.

Thermal stability has been reported as a shared characteristic among some of the major food allergens and appears to have originated from the observation that some cooked foods retain their ability to cause allergic reactions by Immunoglobulin E (IgE) binding and the subsequent cascade of events that mediate allergic reactions. Based on this observation, the thermal stability of novel food proteins, like those in transgenic crops, is considered correlative with allergenic risk and has prompted requests from some regulatory agencies for additional testing to address safety concerns. Because human testing and serum IgE screening are not feasible nor are they necessarily useful for evaluating the thermal stability of a novel food protein, a protein function assay is often used to assess the thermal stability in the context of an allergenicity risk assessment.

Bioinformatics and the allergy assessment of agricultural biotechnology products: industry practices and recommendations.

Bioinformatic tools are being increasingly utilized to evaluate the degree of similarity between a novel protein and known allergens within the context of a larger allergy safety assessment process. Importantly, bioinformatics is not a predictive analysis that can determine if a novel protein will ''become" an allergen, but rather a tool to assess whether the protein is a known allergen or is potentially cross-reactive with an existing allergen. Bioinformatic tools are key components of the 2009 CodexAlimentarius Commission's weight-of-evidence approach, which encompasses a variety of experimental approaches for an overall assessment of the allergenic potential of a novel protein.

Quantitation of soybean allergens using tandem mass spectrometry.

Soybean (Glycine max) seed contain some proteins that are allergenic to humans and animals. However, the concentration of these allergens and their expression variability among germplasms is presently unknown. To address this problem, 10 allergens were quantified from 20 nongenetically modified commercial soybean varieties using parallel, label-free mass spectrometry approaches.

Evaluating biological variation in non-transgenic crops: executive summary from the ILSI Health and Environmental Sciences Institute workshop, November 16-17, 2009, Paris, France.

The International Life Sciences Institute Health and Environmental Sciences Institute Protein Allergenicity Technical Committee hosted an international workshop November 16-17, 2009, in Paris, France, with over 60 participants from academia, government, and industry to review and discuss the potential utility of "-omics" technologies for assessing the variability in plant gene, protein, and metabolite expression. The goal of the workshop was to illustrate how a plant's constituent makeup and phenotypic processes can be surveyed analytically. Presentations on the "-omics" techniques (i.

CYP1A expression in caged rainbow trout discriminates among sites with various degrees of polychlorinated biphenyl contamination.

It has become increasingly apparent that resident fish can develop resistance to chemicals in their environment, thus compromising their usefulness as sentinels of site-specific pollution. By using a stream system whose resident fish appear to have developed pollutant resistance (Brammell et al., Mar Environ Res 58:251-255, 2005), we tested the hypothesis that the pollutant-inducible biomarker, cytochrome P4501A (CYP1A), as measured in field-caged juvenile rainbow trout (Oncorhynchus mykiss), would reflect relative pollution differences between reference and polychlorinated biphenyl (PCB)-contaminated sites.

Scientific advancement of novel protein allergenicity evaluation: an overview of work from the HESI Protein Allergenicity Technical Committee (2000-2008).

The safety assessment of genetically modified crops includes the evaluation for potential allergenicity. The current 'state-of-the-science' utilizes a weight of evidence approach, as outlined by the Codex Alimentarius commission (Alinorm 03/34 A), recognizing no single endpoint is predictive of the allergenic potential of a novel protein. This approach evaluates: whether the gene source is allergenic, sequence similarity to known allergens, and protein resistance to pepsin in vitro.

The use of E-scores to determine the quality of protein alignments.

In 2001, the FAO/WHO suggested a procedure for performing FASTA or BLAST searches, and a threshold of greater than 35% identity in 80 or greater amino acids to identify potential allergenic cross-reactivity of transgene encoded proteins in genetically enhanced crops. Transgene encoded proteins meeting or exceeding this threshold would require additional in vitro evaluation for allergy safety. In work described herein, a method to calculate an E-score threshold is proposed for utilizing the full capability of bioinformatics to accurately identify potential cross-reactive allergens.

Utility of animal models for predicting human allergenicity.

The biochemical characterization of protein structures has led to a better understanding of allergens, their structure/function relationship, and can be very powerful in identifying protein sequences with significant structural similarity to known allergens. However, for scientists, regulators and food manufacturers there exists a need for acquiring additional data on potential allergenicity of proteins, particularly, biotechnology derived molecules in food products for which minimal or no prior human exposure information is available. Since human exposure testing, while direct, is unacceptable, understanding allergy in animals has been used to investigate the allergic response on a molecular level as well as test the potential in vivo allergenicity of food proteins.