Peanut allergy: Emerging concepts and approaches for an apparent epidemic

Disposable amperometric biotool for peanut detection in processed foods by targeting a chloroplast DNA marker

This work reports the development and application of a disposable amperometric sensor built on magnetic microcarriers coupled to an Express PCR strategy to amplify a specific DNA fragment of the chloroplast trnH-psbA. The procedure involves the selective capture of a 68-mer synthetic target DNA (or unmodified PCR products) through sandwich hybridization with RNA capture probe-modified streptavidin MBs and RNA signaling probes, labeled using antibodies specific to the heteroduplexes and secondary antibodies tagged with horseradish peroxidase. Amperometric measurements were performed on screen-printed electrodes using the H2O2/hydroquinone system. Achieving a LOD of 3 pM for the synthetic target, it was possible to detect 2.5 pg of peanut DNA and around 10 mg kg-1 of peanut in binary mixtures (defatted peanut flours prepared in spelt wheat). However, the detectability decreased between 10 and 1000 times in processed samples depending on the treatment. The Express PCR-bioplatform was applied to the detection of peanut traces in foodstuff.

Reported food-related symptoms and food allergen sensitization in a selected adult population in Hyderabad, India: A hospital-based survey

Background

Research on reported food-related triggers of atopic disease in South Asian adults is lacking despite the region's large population and the global significance of allergic diseases.

Objectives

The study aimed to identify prevalent local food items and assess allergic sensitization rates to potential trigger foods for atopic diseases via skin prick and specific IgE testing.

Methods

The study began with a pilot survey of 100 subjects recruited from 4 hospitals in Hyderabad, India, focusing on foods perceived to relate to asthma, allergic rhinitis, atopic dermatitis, urticaria, and gastrointestinal allergic symptoms. A subsequent main study evaluated 2010 participants, 1754 of whom were diagnosed with an aforementioned atopic disease and who reported allergic symptoms related to any of 77 foods identified in the pilot study. Ultimately 1622 patients who consented to skin prick and specific IgE testing and who reported at least 1 food item triggering allergic diseases were included in the final analysis.

Results

Among 1622 patients (average age, 42.6 ± 12.9 years; 55.5% male), asthma was the most commonly diagnosed atopic disease (26.4%), with itching and rash being frequently reported symptoms (22.7%). Notably, 94.9% of patients had total serum IgE > 144 kU/L. Chickpea, cabbage, eggplant, walnut, cumin, and betel leaf were the most commonly reported trigger foods.

Conclusion

In this sample of South Indian adults diagnosed with allergic disease, reported food triggers were most commonly local dietary staples, while reported reactions to priority allergens like peanut and sesame were conspicuously absent. Observed concordance between patient-reported food triggers and sensitization to reported food triggers was low, highlighting the need for improved clinical evaluation of suspected triggers.

Botanical Impurities in the Supply Chain: A New Allergenic Risk Exacerbated by Geopolitical Challenges

BACKGROUND

The supply chains of food raw materials have recently been heavily influenced by geopolitical events. Products that came from, or transited through, areas currently in conflict are now preferentially supplied from alternative areas. These changes may entail risks for food safety.

METHODS

We review the potential allergenicity of botanical impurities, specifically vegetable contaminants, with particular attention to the contamination of vegetable oils. We delve into the diverse types of botanical impurities, their sources, and the associated allergenic potential. Our analysis encompasses an evaluation of the regulatory framework governing botanical impurities in food labeling.

RESULTS

Unintended plant-derived contaminants may manifest in raw materials during various stages of food production, processing, or storage, posing a risk of allergic reactions for individuals with established food allergies. Issues may arise from natural occurrence, cross-contamination in the supply chain, and contamination at during production. The food and food service industries are responsible for providing and preparing foods that are safe for people with food allergies: we address the challenges inherent in risk assessment of botanical impurities.

CONCLUSIONS

The presence of botanical impurities emerges as a significant risk factor for food allergies in the 2020s. We advocate for regulatory authorities to fortify labeling requirements and develop robust risk assessment tools. These measures are necessary to enhance consumer awareness regarding the potential risks posed by these contaminants.

The decrease of Ara h 2 allergenicity by glycation is determined by reducing sugar chain length and isomers

The mechanism of the effect of reducing sugar chain length and isomers on the allergenicity of Ara h 2 after glycation was investigated. Ara h 2 was more prone to glycation with ribose which had a short chain length. The glycation sites of Ara h 2 after glycation with galactose were higher than the glycation sites in galactose's isomers-Ara h 2 conjugates, which might be affected by the configuration differences at position C-4 and the small steric effects in terminal groups -CHO of galactose. Ara h 2-ribose conjugate had the lowest allergenicity, and glycation with galactose was more capable of reducing Ara h 2 allergenicity than its isomers. The results indicated that glycation with ribose caused conformational epitope destruction and linear epitope masking of Ara h 2 greatly. Furthermore, since the small steric effects of -CHO, galactose was more capable of reducing Ara h 2 allergenicity than fructose. This study will provide a theoretical basis for selecting appropriate reducing sugars and preparing hypoallergenic products containing peanuts.

Evidence that High-Affinity IgE Can Develop in the Germinal Center in the Absence of an IgG1-Switched Intermediate

High-affinity allergen-specific IgE is essential for the severe allergic anaphylaxis response. High-affinity Abs are formed by successive rounds of selection of Ag-specific B cells in the germinal center (GC); however, several studies have shown that IgE+ GC B cells are impaired in their ability to undergo selection in the GC. A pathway, known as the "indirect switching pathway" for IgE, has been described whereby Ag-specific B cells initially switch to the IgG1 isotype and undergo affinity selection in the GC, with a secondary switch to the IgE isotype after affinity selection. In previous work, using a food allergy model in mice, we investigated how high-affinity IgE develops in the GC, but we did not test the indirect switching model. In this study, we analyzed the importance of the indirect switching pathway by constructing IgG1-cre Bcl6-fl/fl mice. In these mice, once B cells switch to IgG1, they delete Bcl6 and thus cannot enter or persist in the GC. When we tested IgG1-cre Bcl6-fl/fl mice with our food allergy model, we found that, as expected, IgG1 Abs had decreased affinity, but unexpectedly, the affinity of IgE for allergen was unchanged. IgG1-cre Bcl6-fl/fl mice underwent anaphylaxis in response to allergen, consistent with the formation of high-affinity IgE. Thus, in a food allergy response, high-affinity IgE can be efficiently formed in the absence of indirect switching to IgG1, either by direct selection of IgE+ GC B cells or indirect selection of IgM+ GC B cells that later switch to IgE.

Aryl hydrocarbon receptor: The master regulator of immune responses in allergic diseases

The aryl hydrocarbon receptor (AhR) is a widely studied ligand-activated cytosolic transcriptional factor that has been associated with the initiation and progression of various diseases, including autoimmune diseases, cancers, metabolic syndromes, and allergies. Generally, AhR responds and binds to environmental toxins/ligands, dietary ligands, and allergens to regulate toxicological, biological, cellular responses. In a canonical signaling manner, activation of AhR is responsible for the increase in cytochrome P450 enzymes which help individuals to degrade and metabolize these environmental toxins and ligands. However, canonical signaling cannot be applied to all the effects mediated by AhR. Recent findings indicate that activation of AhR signaling also interacts with some non-canonical factors like Kruppel-like-factor-6 (KLF6) or estrogen-receptor-alpha (Erα) to affect the expression of downstream genes. Meanwhile, enormous research has been conducted to evaluate the effect of AhR signaling on innate and adaptive immunity. It has been shown that AhR exerts numerous effects on mast cells, B cells, macrophages, antigen-presenting cells (APCs), Th1/Th2 cell balance, Th17, and regulatory T cells, thus, playing a significant role in allergens-induced diseases. This review discussed how AhR mediates immune responses in allergic diseases. Meanwhile, we believe that understanding the role of AhR in immune responses will enhance our knowledge of AhR-mediated immune regulation in allergic diseases. Also, it will help researchers to understand the role of AhR in regulating immune responses in autoimmune diseases, cancers, metabolic syndromes, and infectious diseases.

Long-term IgE immunological tolerance to peanut allergens: An alternative to Noon's daily desensitization paradigm

Herein, we show that profound afferent long-term peanut-allergen-specific IgE immunological tolerance for 3 to 9 months induced sustained unresponsiveness (SU) in naïve or peanut-sensitized rodents after peanut allergen immunization. Rodents were vaccinated sublingually with a peanut allergen extract or recombinant peanut allergen in chenodeoxycholate (CDCA), a fanesoid X receptor (FXR, NR1H4) agonist that downregulates SREBP-1c (sterol regulatory element binding protein-1c) and upregulates SHP in bone marrow-derived tolerogenic dendritic cells (DCs). Approximately 90 ∼ 95 % of the total circulating PE-potentiated IgE and Ara h1, Ara h 2, and Ara h 6 peanut allergen-specific IgE responses were suppressed by recombinant peanut allergen-conjugated solid magnetic beads (sensitivity of 0.2 IU/ml). In contrast, peanut allergen-specific IgG production was not affected. Similarly, oleoylethanolamine (OEA), a peroxisome proliferator-activator receptor alpha (PPARα) agonist, and GW9662, a PPARγ antagonist, induced long-term peanut-specific IgE tolerance when administered via the sublingual, oral or i.p. route. Prophylactic Ara h2 DNA immunization with caNRF2 and IL-35 coexpression induced Ara h2 IgE tolerance. In summary, peanut allergen vaccination with select natural molecular ligands of nuclear receptors induced long-term peanut allergen-specific IgE tolerance via the afferent limb, which indicates that vaccination is an immune tolerance-promoting strategy that is effective at the DC level and that differs from Noon's daily desensitization program, which is effective at the mast cell level.

Analysis of Peanut Allergen Components Sensitization and Cross Reaction with Pollen Allergen in Chinese Southerners with Allergic Rhinitis and/or Asthma

Objective

Peanut is one of the most frequently reported allergens causing severe allergies in western countries. In China, however, there have been few reports of severe allergies caused by peanuts. We investigated the peanut allergen components sensitization and cross-reaction with pollen allergen in Chinese Southerners with allergic rhinitis and/or asthma.

Methods

Total IgE (tIgE) and specific IgE (sIgE) antibodies against Ara h 1, Ara h 8, Juglans pollen, Platanus pollen, birch pollen, Bet v 1, Bet v 4, and cross-reactive carbohydrate determinant (CCD) of 58 allergic patients, of whom 33 were peanut-sIgE positive and 25 were negative, were detected by the ImmunoCAP system. The relationships between peanut allergen and pollen allergens were analyzed.

Results

A 9.1% (3/33) of the patients with peanut sensitization were sensitized to Ara h 8, while 21.2% (7/33) were sensitized to Ara h 1. The peanut-sensitized group had significantly higher positive rates for sIgE antibodies against CCD (69.7% vs 4.0%), Juglans pollen (87.9% vs 12.0%), Platanus pollen (90.9% vs 16.0%), and birch pollen (60.6% vs 4.0%) than the peanut tolerance group (all P < 0.05). Spearman correlation showed that peanut-sIgE were significantly correlated with sIgE to CCD (r_s=0.859), Juglans pollen (r_s=0.772), Platanus pollen (r_s=0.838) and birch pollen (r_s=0.816).

Conclusion

The majority of patients sensitized to peanut allergen in Southern China tested positive for multiple pollen allergens. Peanut sensitization was highly correlated with Platanus, Juglans, and birch pollen sensitization, which suggested there may be cross-reactions between peanut and pollen allergens. Clinicians should pay attention to distinguish diagnosis in clinical peanut allergy diagnosis and treatment.

Update of the S2k guideline on the management of IgE-mediated food allergies

Not available.

Effect of ultrasonic pre-treatment on Ara h 1 in peanut sprouts

Ara h 1 is the most abundant sensitizing protein in peanuts; it has high thermal stability and is difficult to degrade. The peanut sprout is a high-quality, natural food that has various beneficial effects and lower allergenicity than peanut seeds. In this study, ultrasonication (US) of peanut sprouts was used to alter their Ara h 1 content. We determined that the optimal parameters for the US process were 35 °C temperature, 30 min duration, 240 W power, and 100 kHz frequency. After 5 days of germination, the protease activity of the control (blank) group increased to 262.39 ± 0.10 U, whereas that of the US group increased to 290.1 ± 0.25 U. We also investigated the effects of US on Ara h 1 protein composition, structure, and related gene expression during germination. ELISA results showed that after 5 days of germination, Ara h 1 content in the blank group decreased from 20.63 ± 0.31 ppm to 3.35 ± 0.42 ppm, whereas in the US group, they decreased to below the detection limit. SDS-PAGE bands between 50 and 70 kDa from peanut sprout extracts gradually became lighter in both groups. The band almost disappeared at day 5 of germination in the US group, indicating that US reduced the Ara h 1 content of peanut sprouts, consistent with the ELISA results. The expression of the Ara h 1 gene in peanut seeds was 173.92 ± 26.37. In the BK control group, it decreased to 0.49 ± 0.17 on the fourth day and increased slightly to 0.75 ± 0.09 on the fifth day. In the US group, it decreased to 1.37 ± 0.28 on the first day, dropped sharply to 0.00 on the third day, and increased slightly to 0.04 ± 0.01 on the fourth and fifth days. Protein structure results showed that the α-helix structure of Ara h 1 decreased after US, whereas the content of β-fold structures increased. The surface hydrophobicity decreased, and the secondary and tertiary structures of Ara h 1 were loose.

A Snapshot on Food Allergies: A Case Study on Edible Flowers

This perspective study addresses the main causes of adverse reactions to foods in humans, by taking into account the main allergic reactions that may occur as a result of food ingestion, as well the main allergens present in food and how their allergenicity change as a result of food preparation. In addition, European legislation on food labeling and novel foods was taken into account. The case study of this perspective is on the potential allergenicity of edible flowers as well as evidence of phytochemistry and toxic compounds and the risk associated with their ingestion. Regarding edible flowers, a key issue to address is if they are safe to consume or not. In the framework of the project “Innovative activities for the development of the cross-border supply chain of the edible flower” (ANTEA), we considered 62 different species and varieties of edible flowers. The results obtained by consulting two databases on allergens, COMPRISE and Allergen Nomenclature, marked two alerts for two species of edible flowers selected in the project. Moreover, based on edible flower consumption, about ten grams per serving, and on their protein content, we can also state that the risk of allergic reactions due to edible flower ingestion is very low.

Peanut allergy impact on productivity and quality of life (PAPRIQUA): Caregiver-reported psychosocial impact of peanut allergy on children

BACKGROUND

Limited research has examined the impact of peanut allergy (PA) on children using validated instruments to assess psychosocial burden and the factors influencing burden.

OBJECTIVE

The PAPRIQUA study aimed to assess the caregiver-reported impact of living with PA on children's health-related quality of life (HRQL), correlations between PA severity and child's sex, and associations of caregivers' sex and anxiety with the proxy report of their child's HRQL and to identify significant predictors of a child's HRQL.

METHODS

A cross-sectional survey of caregivers of children with mild, moderate and severe PA, based on caregiver perception, was conducted in the United Kingdom. Participants were recruited through a survey recruitment panel; a maximum quota of 20% who rated their child's PA as mild was set to ensure population diversity; however, the quota was not required as few participants considered their child's PA mild. The survey, funded by Aimmune Therapeutics, included sociodemographic and clinical questions, the EQ-5D-Y, Hospital Anxiety and Depression Scale, Food Allergy Quality of Life Questionnaire-Parent Form (FAQLQ-PF) and Food Allergy Independent Measure (FAIM).

RESULTS

One hundred caregivers of children with PA (aged 4-15 years) completed the survey. Child's sex was not associated with proxy-reported burden. For younger children (aged 4-10 years), there was no effect of PA severity; parents of older children (aged 11-15 years) reported low to higher burden for their child on the EQ-5D-Y and FAQLQ-PF dependent upon PA severity. For all measures of child burden except the EQ-5D-Y, two or more reactions in the past 12 months and parental anxiety significantly predicted higher levels of burden for the child (P < .05-P < .001). Experiencing a life-threatening event in the past 12 months significantly predicted EQ-5D-Y proxy utility (P < .01).

CONCLUSIONS AND CLINICAL RELEVANCE

Caregivers report that children with PA experience high levels of psychosocial burden, particularly those with more severe PA and a reaction history. Interventions to decrease caregiver anxiety and reaction frequency may help reduce the child's burden. Self-report studies in children with PA would help confirm these findings.

T follicular regulatory cells and IL-10 promote food antigen-specific IgE

Food allergies are a major clinical problem and are driven by IgE antibodies (Abs) specific for food antigens (Ags). T follicular regulatory (Tfr) cells are a specialized subset of FOXP3+ T cells that modulate Ab responses. Here, we analyzed the role of Tfr cells in regulating Ag-specific IgE using a peanut-based food allergy model in mice. Peanut-specific IgE titers and anaphylaxis responses were significantly blunted in Tfr cell-deficient Foxp3-Cre Bcl6fl/fl mice. Loss of Tfr cells led to greatly increased nonspecific IgE levels, showing that Tfr cells have both helper and suppressor functions in IgE production in the germinal center (GC) that work together to facilitate the production of Ag-specific IgE. Foxp3-Cre Ptenfl/fl mice with augmented Tfr cell responses had markedly higher levels of peanut-specific IgE, revealing an active helper function by Tfr cells on Ag-specific IgE. The helper function of Tfr cells for IgE production involves IL-10, and the loss of IL-10 signaling by B cells led to a severely curtailed peanut-specific IgE response, decreased GCB cell survival, and loss of GC dark zone B cells after peanut sensitization. We thus reveal that Tfr cells have an unexpected helper role in promoting food allergy and may represent a target for drug development.

The influence of cultural attitudes to nut exposure on reported nut allergy: A pilot cross sectional study

Food allergies in children have become a common management and diagnostic concern and have a significant influence on general health-related quality of life. We investigated the prevalence of reported nut allergy between populations with different cultural attitudes to nuts during pregnancy and infancy. We conducted a survey to investigate the relationship between cultural differences in the consumption of nuts during pregnancy, breastfeeding and exposure to nuts in early childhood against the reported prevalence of nut allergy between three populations: Libyan, UK Libyan and a general UK population. The survey was administered to a representative sample of UK and Libyan parents with children aged between 3 and 16 years who were asked to report prevalence of nut allergy and to describe the factors that might affect this such as cultural behaviours and diet. A total of 1,123 parents responded. Nut allergy was defined as an allergic reaction that required medical treatment. The reported rates of nut allergy showed a significant difference in nut allergy between the Libyan populations and the general UK population with an increased odds ratio of nut allergy of ~10 when comparing the Native Libyan population to the UK population. The UK Libyan population reported the same low rate of allergic reactions as the Libyan population which were both significantly lower than the UK population (p < .0001). The Libyan populations showed significant differences from the UK population in exposure to nuts during pregnancy, breastfeeding and early infancy. The development of peanut and almond allergy through tolerance induction could be prevented by frequent and early ingestion of a moderate quantity of nuts during infancy and by maternal ingestion during pregnancy or lactation.

Peanut allergy diagnosis: Moving from basic to more elegant testing

Peanut allergy (PNA) is an IgE-mediated immune disorder, which merits particular attention due to its impact on the health and quality of life of millions of patients worldwide. PNA tends to develop in early life and resolves in only 20% of peanut-allergic children. It accounts for the majority of severe food-related allergic reactions. An accurate diagnosis of PNA is vital. In this review, we present the approach to the diagnosis of peanut allergy, starting from the history and proceeding to measures of overall sensitization and then to component-resolved diagnostics and oral food challenges as indicated. Additional testing in development includes basophil activation testing and determination of epitopes for peanut-allergic responses. Based on the literature, stepwise approaches and predictive models for diagnosing PNA are also presented.

Changes Induced by Pressure Processing on Immunoreactive Proteins of Tree Nuts

Tree nuts confer many health benefits due to their high content of vitamins and antioxidants, and they are increasingly consumed in the last few years. Food processing is an important industrial tool to modify allergenic properties of foods, in addition to ensuring safety and enhancing organoleptic characteristics. The effect of high pressure, without and with heating, on SDS-PAGE and immunodetection profile of potential allergenic proteins (anti-11S, anti-2S and anti-LTP) of pistachio, cashew, peanut, hazelnut, almond, and chestnut was investigated. Processing based on heat and/or pressure and ultra-high pressure (HHP, 300-600 MPa) without heating was applied. After treating the six tree nuts with pressure combined with heat, a progressive diminution of proteins with potential allergenic properties was observed. Moreover, some tree nuts proteins (pistachio, cashew, and peanut) seemed to be more resistant to technological processing than others (hazelnut and chestnut). High pressure combined with heating processing markedly reduce tree nut allergenic potential as the pressure and treatment time increases. HHP do not alter hazelnut and almond immunoreactivity.

A 5-year retrospective review of children with peanut allergy in the largest paediatric hospital in Singapore

Background

The prevalence of peanut allergy (PA) among children has increased significantly over the past decade. Even though the prevalence of PA in Singapore is considered low, peanut is the top trigger for food-induced anaphylaxis in Singaporean children.

Objective

To describe the demographic characteristics and clinical features of children with PA.

Methods

This is a 5-year retrospective review of children diagnosed with PA based on clinical history coupled with a positive skin prick test to peanut or positive oral food challenge results.

Results

There were 269 patients (53.9% males) with a clinical diagnosis of PA. The median age at first allergic presentation for the PA group was 24 months old, with interquartile range of 13-39 months. The most common form of peanut introduced was roasted peanut. The rate of peanut anaphylaxis was 7.1%. Concomitant tree nut sensitization was found in 32.3% of this cohort, predominantly to cashew nut. Majority of them have a personal history of atopy - 75.8% with eczema, 63.6% with allergic rhinitis, and 19.7% with asthma.

Conclusion

This is the first large review of peanut-allergic children in Singapore. Prospective population-based studies are needed to establish the true prevalence and risk factors associated with the development of this potentially life-threatening condition.

Silkworm dropping extract regulates food allergy symptoms via inhibition of Th2-related responses in an ovalbumin-induced food allergy model

BACKGROUND

Silkworm droppings have long been used in traditional medicine to remedy allergic itching, palsy, blood circulation problems, and arthritis in Asian countries. To investigate the anti-allergic effect of silkworm dropping extract (SDE) and its mechanism, we used a mouse model of food allergy induced by ovalbumin (OVA).

RESULTS

SDE ameliorated the symptoms of OVA-induced food allergies, and the levels of T helper 2 (Th2)-related cytokines [such as interleukin (IL)-4, IL-5, IL-10, and IL-13] were found to be significantly decreased in both the spleen and mesenteric lymph nodes by SDE. Furthermore, SDE treatment directly inhibited OVA permeation, IL-4 production, and degranulation of mast cells; in contrast, immunoglobulin E (IgE) production from B cells was not affected.

CONCLUSION

These results suggest that SDE has potential anti-allergic activities, and SDE may be useful in the treatment/prevention of allergic disorders such as food allergies, serving as therapeutic agents. © 2019 Society of Chemical Industry.

Hypoallergen Peanut Lines Identified Through Large-Scale Phenotyping of Global Diversity Panel: Providing Hope Toward Addressing One of the Major Global Food Safety Concerns

Peanut allergy is one of the serious health concern and affects more than 1% of the world's population mainly in Americas, Australia, and Europe. Peanut allergy is sometimes life-threatening and adversely affect the life quality of allergic individuals and their families. Consumption of hypoallergen peanuts is the best solution, however, not much effort has been made in this direction for identifying or developing hypoallergen peanut varieties. A highly diverse peanut germplasm panel was phenotyped using a recently developed monoclonal antibody-based ELISA protocol to quantify five major allergens. Results revealed a wide phenotypic variation for all the five allergens studied i.e., Ara h 1 (4-36,833 µg/g), Ara h 2 (41-77,041 µg/g), Ara h 3 (22-106,765 µg/g), Ara h 6 (829-103,892 µg/g), and Ara h 8 (0.01-70.12 µg/g). The hypoallergen peanut genotypes with low levels of allergen proteins for Ara h 1 (4 µg/g), Ara h 2 (41 µg/g), Ara h 3 (22 µg/g), Ara h 6 (829 µg/g), and Ara h 8 (0.01 µg/g) have paved the way for their use in breeding and genomics studies. In addition, these hypoallergen peanut genotypes are available for use in cultivation and industry, thus opened up new vistas for fighting against peanut allergy problem across the world.

Effectiveness of different proteases in reducing allergen content and IgE-binding of raw peanuts

The effectiveness of some non-specific proteases in reducing raw peanut allergenicity was investigated. Peanut kernels were treated by Alcalase, papain, Neutrase and bromelain, respectively. The residues of major peanut allergens Ara h 1, Ara h 2 and Ara h 6 were determined by sandwich ELISA and SDS-PAGE, and the allergenicities of treated peanuts were compared to that of untreated peanuts by western blot. All tested proteases were effective in reducing Ara h 1, but their effectiveness in hydrolyzing Ara h 2 and Ara h 6 varied greatly. The maximal reductions of extractable Ara h 1, Ara h 2 and Ara h 6 were 100%, 100% and 99.8%, respectively, achieved by Alcalase hydrolysis. Alcalase was more effective in overall allergenicity reduction; bromelain and Neutrase were the least effective in reducing Ara h 2 and Ara h 6, respectively. The hydrolysis of original allergens also produced some smaller peptides with strong IgE-binding.

Interleukin-13 Is Unlucky for Allergy Sufferers

Anaphylaxis, a life-threatening allergic reaction, is dependent on high affinity allergen-specific IgE. Gowthaman et al. now show that a new interleukin (IL)-13-expressing T helper cell subset specifically promotes high-affinity IgE responses. The discovery of T follicular helper (Tfh)13 cells defines potential new targets for allergy therapies.

Allergic Comorbidity in Eosinophilic Esophagitis: Mechanistic Relevance and Clinical Implications

Allergic eosinophilic esophagitis (EoE) is a chronic, allergen-mediated inflammatory disease of the esophagus, and the most common cause of prolonged dysphagia in children and young adults in the developed world. While initially undistinguished from gastroesophageal reflux disease-associated esophageal eosinophilia, EoE is now recognized as a clinically distinct entity that shares fundamental inflammatory features of other allergic conditions and is similarly increasing in incidence and prevalence. The clinical and epidemiologic associations between EoE and other allergic manifestations are well established. In addition to exaggerated rates of atopic dermatitis, IgE-mediated food allergy, asthma, and allergic rhinitis in EoE patients, each of these allergic manifestations imparts individual and cumulative risk for subsequent EoE diagnosis. As such, EoE may be a member of the "allergic march"-the natural history of allergic manifestations during childhood. Several determinants likely contribute to the relationship between these conditions, including shared genetic, environmental, and immunologic factors. Herein, we present a comprehensive review of allergic comorbidity in EoE. We discuss areas of the genome associated with both EoE and other allergic diseases, including the well-studied variants encoding thymic stromal lymphopoietin and calpain 14, among other "atopic" regions. We summarize ways that environmental factors (such as microbiome-altering pressures and aeroallergen exposure) may predispose to multiple allergic conditions including EoE. Finally, we touch on some fundamental features of type 2 inflammation, and the resulting implications for the development of multiple allergic manifestations. We conclude with an analysis of the "type 2" biologics, and how mechanistic similarities between EoE and the other allergic manifestations have important implications for screening and treatment of the allergic patient.

An Improved Enzyme-Linked Immunosorbent Assay (ELISA) Based Protocol Using Seeds for Detection of Five Major Peanut Allergens Ara h 1, Ara h 2, Ara h 3, Ara h 6, and Ara h 8

Peanut allergy is an important health concern among many individuals. As there is no effective treatment to peanut allergy, continuous monitoring of peanut-based products, and their sources is essential. Precise detection of peanut allergens is key for identification and development of improved peanut varieties with minimum or no allergens in addition to estimating the levels in peanut-based products available in food chain. The antibody based ELISA protocol along with sample preparation was standardized for Ara h 1, Ara h 2, Ara h 3, Ara h 6, and Ara h 8 to estimate their quantities in peanut seeds. Three different dilutions were optimized to precisely quantify target allergen proteins in peanut seeds such as Ara h 1 (1/1,000, 1/2,000, and 1/4,000), Ara h 2 and Ara h 3 (1/5,000, 1/10,000, and 1/20,000), Ara h 6 (1/40,000, 1/80,000, and 1/1,60,000), and Ara h 8 (1/10, 1/20, and 1/40). These dilutions were finalized for each allergen based on the accuracy of detection by achieving <20% coefficient of variation in three technical replicates. This protocol captured wide variation of allergen proteins in selected peanut genotypes for Ara h 1 (77-46,106 μg/g), Ara h 2 (265-5,426 μg/g), Ara h 3 (382-12,676 μg/g), Ara h 6 (949-43,375 μg/g), and Ara h 8 (0.385-6 μg/g). The assay is sensitive and reliable in precise detection of five major peanut allergens in seeds. Deployment of such protocol allows screening of large scale germplasm and breeding lines while developing peanut varieties with minimum allergenicity to ensure food safety.

Evaluation of AdvanSure AlloScreen Max Panel With 92 Different Allergens for Detecting Allergen-Specific IgE

OBJECTIVES

The objective of this study was to examine the performance of AdvanSure AlloScreen Max with 92 different allergens compared to Polycheck Allergy and ImmunoCAP. The relationship of serum IgE concentration with the number and the highest class/level of positive allergen-specific IgEs was also examined.

METHODS

A total of 406 serum samples were included in this study. Discrepant cases between AdvanSure AlloScreen Max and Polycheck Allergy underwent ImmunoCAP testing for allergen-specific IgE.

RESULTS

Total agreement of the two multiple allergen simultaneous tests (MAST) was 92.5%. Compared to ImmunoCAP, total agreement rate was higher with AdvanSure AlloScreen Max (60.8%) than that with Polycheck Allergy (39.2%). Serum IgE concentration showed a significant and positive correlation with the number and the highest class/level of positive allergen-specific IgEs.

CONCLUSIONS

A MAST assay panel containing as many allergens as possible would be more helpful in the allergen screening for patients with high serum IgE concentration.

Different thermal processing effects on peanut allergenicity

BACKGROUND

Peanut allergy is one of the most common food allergies worldwide. Studies have shown that the incidence of peanut allergies in Western-born Asians is higher than that in Asia-born Asians. Notably, Europeans and Americans mostly eat roasted peanuts, whereas Asians mostly eat boiled or fried peanuts.

RESULTS

BALB/c mice were sensitized using purified protein from raw, roasted or boiled peanuts, then fed the same by oral gavage. The relevant allergic reactions were studied using BALB/c mice model, including a rat basophilic leukemia (RBL) cell model, simulated gastric fluid experiments, and ultraviolet (UV) and circular dichroism (CD) spectral analysis. Serological studies showed increased levels of immunoglobulin E, interleukin-4 and interleukin-5, and pathological studies showed mast cell degranulation and inflammatory changes in jejunal tissues, with an increase in thymic stromal lymphopoietin (TSLP) gene expression in all treatment groups compared with the control group (phosphate-buffered saline). Compared with the raw peanut group, sera from the roasted peanut group produced a significant increase in RBL β-hexosaminidase A release in vitro, and roasted peanuts showed increased resistance to digestion in simulated gastric fluid experiments. Ultraviolet and CD spectral analyses showed that the roasting and boiling processes altered the structure of the major peanut allergens, which may have contributed to the differences observed in peanut allergenicity.

CONCLUSION

Our findings indicate that peanut allergies are related to peanut thermal processing methods. In our mouse model, the raw, roasted and boiled peanuts elicited different degrees of allergic response. Compared with raw peanut, roasted peanuts show a higher allergenicity, whereas the boiled peanuts show a lower allergenicity. © 2018 Society of Chemical Industry.

Early Infant Risk Factors for Pediatric Eosinophilic Esophagitis

OBJECTIVES

Eosinophilic esophagitis (EoE) is an inflammatory, atopic disease of the esophagus without a clear etiology. Our objective was to identify exposures and conditions in early infancy associated with the development of EoE.

METHODS

A case-control study was performed using the Military Health System Database. Subjects diagnosed with EoE from October 2008 to September 2015 were matched 1:2 on age and sex. Early infant risk factors from the first 6 months of life were investigated.

RESULTS

A total of 1410 cases with EoE were matched to 2820 controls. The median (interquartile range) age at diagnosis of EoE was 4.2 years (2.1-7.2) and 68.7% were boys. Proton pump inhibitors (adjusted odds ratio [aOR], 2.73; 95% confidence interval [CI] 1.93-3.88), histamine-2 receptor antagonists (aOR, 1.64; 95% CI 1.27-2.13), and antibiotics (aOR, 1.31; 95% CI 1.10-1.56) were associated with EoE. Prematurity (aOR, 1.46; 95% CI 1.12-1.89) and early manifestations of atopic disease such as milk protein allergy (aOR, 2.37; 95% CI 1.26-4.44) and eczema (aOR, 1.97; 95% CI 1.64-2.36) were related to increased odds for EoE. Erythema toxicum in infancy was strongly associated with a diagnosis of EoE (aOR 3.52; 95% CI 1.03-12.04). Infants with feeding difficulty (aOR, 1.45; 95% CI 1.18-1.77) and gastroesophageal reflux disease (aOR, 1.79; 96% CI 1.43-2.26) were also at increased risk for EoE.

CONCLUSIONS

Acid-blocking medications and antibiotics during infancy were associated with later diagnosis of EoE. Erythema toxicum neonatorum, an eosinophilic immune phenomenon, was strongly associated with EoE. Identifying early infant risk factors for EoE may help to risk stratify the need for endoscopy.

Development and Evaluation of a Real-Time PCR Multiplex Assay for the Detection of Allergenic Peanut Using Chloroplast DNA Markers

Peanut is one of the most commonly consumed allergy-causing foods in the United States. Prevention of accidental consumption by allergic individuals is assisted by methods that effectively identify the presence of peanut in food, even at trace levels. This study presents a multiplex real-time polymerase chain reaction (PCR) assay that uses chloroplast markers ( matK, rpl16, and trnH-psbA) to specifically detect peanut in three types of foods: baked goods, chocolate, and tomato sauces. Food matrices were spiked with raw peanut at concentrations ranging from 0.1 to 10⁵ ppm. The assay was evaluated with respect to linear range and reaction efficiency. High reaction efficiencies were generally obtained across 6-7 orders of magnitude. Limits of detection were between 0.1 and 1 ppm, and reaction efficiencies were mostly within the preferred range of 100 ± 10%. Our results indicate that real-time PCR assays using chloroplast markers can be a valuable tool for peanut detection.

Long-term outcome of peanut oral immunotherapy-Real-life experience

BACKGROUND

Oral immunotherapy (OIT) is currently recommended as a treatment option for peanut-allergic patients. Data regarding its long-term compliance and efficacy in real life are required.

METHODS

Peanut-allergic patients aged ≥4 years were enrolled in a single-center clinical OIT program. Buildup to 3000 mg peanut protein was performed. Patients reaching this dose before or after 12/2014 were instructed to consume 3000 or 1200 mg daily, respectively. Patients were followed ≥6 months after reaching maintenance and rechallenged to 3000 mg.

RESULTS

Of the 145 patients studied, 113 (77.9%) were fully desensitized to 3000 mg and 133 (91.7%) were desensitized to ≥300 mg. 21/145 patients (14.5%) required adrenaline for home-dose reactions during buildup. Non-anaphylactic gastrointestinal symptoms, experienced by 9 patients (6.2%), reversed with dose reduction. Of the 111 patients available for analysis 6 months after reaching 3000 mg, 97 (87.4%) continued regular peanut consumption. Only 2/111 patients (1.8%) required adrenaline over the long-term (median, range; 18, 6-75 months) follow-up. Adherence to treatment was significantly higher in patients consuming 1200 mg (73/76, 96.1%) vs those consuming 3000 mg (24/35, 72.2%), (P = .001). A higher maintenance dosage and home adrenaline requirement during buildup predicted adherence cessation (OR 12.5, P = .001; and OR 7.8, P = .02, respectively). 63/64 patients (98.4%) consuming 1200 mg maintenance dose were successfully rechallenged to 3000 mg.

CONCLUSIONS

This real-life experience demonstrates the efficacy of peanut OIT long-term. A lower maintenance dose minimized treatment cessation while maintaining desensitization. OIT should be performed in qualified centers given the prevalence of adverse reactions, particularly during buildup.

BSACI guideline for the diagnosis and management of peanut and tree nut allergy

Peanut nut and tree nut allergy are characterised by IgE mediated reactions to nut proteins. Nut allergy is a global disease. Limited epidemiological data suggest varying prevalence in different geographical areas. Primary nut allergy affects over 2% of children and 0.5% of adults in the UK. Infants with severe eczema and/or egg allergy have a higher risk of peanut allergy. Primary nut allergy presents most commonly in the first five years of life, often after the first known ingestion with typical rapid onset IgE-mediated symptoms. The clinical diagnosis of primary nut allergy can be made by the combination of a typical clinical presentation and evidence of nut specifc IgE shown by a positive skin prick test (SPT) or specific IgE (sIgE) test. Pollen food syndrome is a distinct disorder, usually mild, with oral/pharyngeal symptoms, in the context of hay fever or pollen sensitisation, which can be triggered by nuts. It can usually be distinguish clinically from primary nut allergy. The magnitude of a SPT or sIgE relates to the probability of clinical allergy, but does not relate to clinical severity. SPT of ≥ 8 mm or sIgE ≥ 15 KU/L to peanut is highly predictive of clinical allergy. Cut off values are not available for tree nuts. Test results must be interpreted in the context of the clinical history. Diagnostic food challenges are usually not necessary but may be used to confirm or refute a conflicting history and test result. As nut allergy is likely to be a long-lived disease, nut avoidance advice is the cornerstone of management. Patients should be provided with a comprehensive management plan including avoidance advice, patient specific emergency medication and an emergency treatment plan and training in administration of emergency medication. Regular re-training is required.

Contribution of Molecular Allergen Analysis in Diagnosis of Milk Allergy

PURPOSE OF REVIEW

We sought to describe the available evidence supporting the utilization of the molecular allergen analysis (MAA) for diagnosis and management of cow milk protein allergy (CMPA).

RECENT FINDINGS

Cow milk proteins are among the most common food allergens in IgE- and non-IgE-mediated food allergic disorders in children. Most individuals with CMPA are sensitized to both caseins and whey proteins. Caseins are more resistant to high temperatures compared to whey proteins. MAA is not superior to the conventional diagnostic tests based on the whole allergen extracts for diagnosis of CMPA. However, MAA can be useful in diagnosing tolerance to extensively heated milk proteins in baked foods. Children with CMPA and high levels of casein IgE are less likely to tolerate baked milk compared to children with low levels of casein IgE. Specific IgE-binding patterns to casein and betalactoglobulin peptides may predict the natural course of CMPA and differentiate subjects who are more likely to develop CMPA at a younger age versus those with a more persistent CMPA. Specific IgE-binding patterns to casein and beta-lactoglobulin peptides may also predict response to milk OITand identify patientsmost likely to benefit fromOIT.

Lupin and Other Potentially Cross-Reactive Allergens in Peanut Allergy

PURPOSE OF REVIEW

The presence of IgE cross-reactivity between peanut allergens and allergens from other legumes and tree nuts has been demonstrated, but the identification of the involved individual allergens is still limited. The aim of this review is to describe new allergenic findings, of potential relevance for cross-reactivity among peanut and lupin.

RECENT FINDINGS

Seventeen allergens of peanut have been included in the official allergen nomenclature database to date. Lupin sensitization has been observed in 15-20% of individuals with known peanut allergy, The majority of lupin seed proteins are comprised of α-conglutins (legumin-like) and β-conglutins (vicilin-like), and to a lesser extent γ-conglutins (vicilin-like) and δ-conglutins (2S albumins). Several molecules may fuel peanut-lupin cross-reactivity. Awareness among physicians and general public could avoid unexpected allergic reactions. However, these do not appear frequent and no data suggest a precautionary labelling of lupin in foods.

Allergen immunotherapy for IgE-mediated food allergy: a systematic review and meta-analysis

BACKGROUND

The European Academy of Allergy and Clinical Immunology (EAACI) is developing Guidelines for Allergen Immunotherapy (AIT) for IgE-mediated Food Allergy. To inform the development of clinical recommendations, we sought to critically assess evidence on the effectiveness, safety and cost-effectiveness of AIT in the management of food allergy.

METHODS

We undertook a systematic review and meta-analysis that involved searching nine international electronic databases for randomized controlled trials (RCTs) and nonrandomized studies (NRS). Eligible studies were independently assessed by two reviewers against predefined eligibility criteria. The quality of studies was assessed using the Cochrane Risk of Bias tool for RCTs and the Cochrane ACROBAT-NRS tool for quasi-RCTs. Random-effects meta-analyses were undertaken, with planned subgroup and sensitivity analyses.

RESULTS

We identified 1814 potentially relevant papers from which we selected 31 eligible studies, comprising of 25 RCTs and six NRS, studying a total of 1259 patients. Twenty-five trials evaluated oral immunotherapy (OIT), five studies investigated sublingual immunotherapy, and one study evaluated epicutaneous immunotherapy. The majority of these studies were in children. Twenty-seven studies assessed desensitization, and eight studies investigated sustained unresponsiveness postdiscontinuation of AIT. Meta-analyses demonstrated a substantial benefit in terms of desensitization (risk ratio (RR) = 0.16, 95% CI 0.10, 0.26) and suggested, but did not confirm sustained unresponsiveness (RR = 0.29, 95% CI 0.08, 1.13). Only one study reported on disease-specific quality of life (QoL), which reported no comparative results between OIT and control group. Meta-analyses revealed that the risk of experiencing a systemic adverse reaction was higher in those receiving AIT, with a more marked increase in the risk of local adverse reactions. Sensitivity analysis excluding those studies judged to be at high risk of bias demonstrated the robustness of summary estimates of effectiveness and safety of AIT for food allergy. None of the studies reported data on health economic analyses.

CONCLUSIONS

AIT may be effective in raising the threshold of reactivity to a range of foods in children with IgE-mediated food allergy whilst receiving (i.e. desensitization) and post-discontinuation of AIT. It is, however, associated with a modest increased risk in serious systemic adverse reactions and a substantial increase in minor local adverse reactions. More data are needed in relation to adults, long term effects, the impact on QoL and the cost-effectiveness of AIT.

Lactobacillus buchneri S-layer as carrier for an Ara h 2-derived peptide for peanut allergen-specific immunotherapy

Peanut allergy is an IgE-mediated severe hypersensitivity disorder. The lack of a treatment of this potentially fatal allergy has led to intensive research on vaccine development. Here, we describe the design and initial characterization of a carrier-bound peptide derived from the most potent peanut allergen, Ara h 2, as a candidate vaccine. Based on the adjuvant capability of bacterial surface (S-) layers, a fusion protein of the S-layer protein SlpB from Lactobacillus buchneri CD034 and the Ara h 2-derived peptide AH3a42 was produced. This peptide comprised immunodominant B-cell epitopes as well as one T cell epitope. The fusion protein SlpB-AH3a42 was expressed in E. coli, purified, and tested for its IgE binding capacity as well as for its ability to activate sensitized rat basophil leukemia (RBL) cells. The capacity of Ara h 2-specific IgG rabbit-antibodies raised against SlpB-AH3a42 or Ara h 2 to inhibit IgE-binding was determined by ELISA inhibition assays using sera of peanut allergic patients sensitized to Ara h 2. IgE specific to the SlpB-AH3a42 fusion protein was detected in 69% (25 of 36) of the sera. Despite the recognition by IgE, the SlpB-AH3a42 fusion protein was unable to induce β-hexosaminidase release from sensitized RBL cells at concentrations up to 100ng per ml. The inhibition of IgE-binding to the natural allergen observed after pre-incubation of the 20 sera with rabbit anti-SlpB-AH3a42 IgG was more than 30% for four sera, more than 20% for eight sera, and below 10% for eight sera. In comparison, anti-Ara h 2 rabbit IgG antibodies inhibited binding to Ara h 2 by 48% ±13.5%. Our data provide evidence for the feasibility of this novel approach towards the development of a peanut allergen peptide-based carrier-bound vaccine. Our experiments further indicate that more than one allergen-peptide will be needed to induce a broader protection of patients allergic to Ara h 2.

Trends, characteristics, and incidence of anaphylaxis in 2001-2010: A population-based study

BACKGROUND

Anaphylaxis is a potentially life-threatening systemic allergic reaction.

OBJECTIVE

We aimed to determine the incidence rate and causes of anaphylaxis during a 10-year period in Olmsted County, Minnesota.

METHODS

Using the resources of the Rochester Epidemiology Project, a comprehensive records linkage system, we performed a population-based incidence study in Olmsted County, Minnesota, from 2001 through 2010. All cases with a diagnosis of anaphylactic shock and 20% of cases with related diagnoses were manually reviewed. The relationships of age group, sex, and year of anaphylaxis with incidence rates were assessed by fitting Poisson regression models.

RESULTS

Six hundred thirty-one cases of anaphylaxis were identified. The median age was 31 years (interquartile range, 19-44 years). The overall age- and sex-adjusted incidence rate was 42 (95% CI, 38.7-45.3) per 100,000 person-years. There was a significant increase in the overall incidence of anaphylaxis during the study period, with an average increase of 4.3% per year (P < .001). In addition, there was a 9.8% increase per year in the incidence rate of food-related anaphylaxis. Food-related anaphylaxis was most common in children aged 0 to 9 years, venom-related anaphylaxis was most common in those 20 to 39 years of age, and medication-related anaphylaxis was most common in those 30 to 39 years of age.

CONCLUSION

The overall incidence rate of anaphylaxis was 42 per 100,000 person-years from 2001-2010 in Olmsted County, Minnesota. The incidence of anaphylaxis increased over time, and several inciting triggers were uniquely associated with different age groups.

Clinical Management of Psychosocial Concerns Related to Food Allergy

Current estimates indicate that 4% to 8% of children in the United States are diagnosed with food allergy, and more than 40% of US children with food allergy experience severe allergic reactions. Families trying to avoid foods that may trigger an allergic reaction and ensure adequate treatment of allergic reactions that do occur face numerous challenges. The rise in the number of children diagnosed with food allergies underscores the importance of food allergy-related interventions to address elevated psychosocial concerns, such as parenting stress, anxiety, and worries about bullying. This review provides an overview of common psychosocial concerns among children with food allergy and their families across the developmental spectrum, and offers guidance to medical providers regarding the identification and treatment of food allergy-related psychosocial challenges.

Astragaloside IV ameliorates allergic inflammation by inhibiting key initiating factors in the initial stage of sensitization

To illuminate the anti-allergy mechanism of astragaloside IV (AS-IV), we assessed its effects in a murine model of allergic contact dermatitis (ACD). AS-IV administered in the sensitization phase, rather than in the elicitation phase, dramatically alleviated the symptoms of allergic inflammation. We hypothesized that AS-IV exerts its anti-allergy effects by regulating the production of key pro-allergic cytokines based on the fact that interleukin (IL)-33 and thymic stromal lymphopoietin (TSLP) levels increase significantly in the initial stage of the sensitization phase. AS-IV administered in the initial stage of ACD inhibited TSLP and IL-33 expression and reduced the proportion of type-2 innate lymphoid cells (ILC2s). An in vitro study showed that the production of pro-allergic cytokines was significantly inhibited in AS-IV presenting HaCaT cells. We also verified that AS-IV administered only in the initial stage markedly alleviated inflammation, including ear swelling, Th2 cytokine expression, and histological changes. Taken together, these results suggest that AS-IV effectively ameliorates the progression of allergic inflammation by inhibiting key initiating factors, including TSLP and IL-33, and can be used to prevent and/or treat patients with ACD. Our data also suggest that these key pro-allergic cytokines are potential therapeutic targets for allergic diseases.

Clinical Significance of Component Allergens in Fagales Pollen-Sensitized Peanut Allergy in Korea

PURPOSE

Clinical features of peanut allergy can range from localized to systemic reactions. Because peanut and birch pollen have cross-reactivity, peanut can lead to localized allergic reaction in Fagales pollen-sensitized oral allergy syndrome (OAS) patients without peanut sensitization per se. The purpose of this study was to discriminate true peanut food allergy from cross-reactive hypersensitivity in birch-sensitized peanut allergy.

METHODS

Birch-sensitized (n=81) and peanut anaphylaxis patients (n=12) were enrolled. Peanut-related allergic reactions and sensitization profiles were examined. Specific IgE to Fagales tree pollens (birch, oak), peanut, and their component allergens (Bet v 1, Bet v 2, Ara h 1, Ara h 2, Ara h 3, Ara h 8, and Ara h 9) were evaluated. Based on these specific IgEs and clinical features, the patients were classified into 4 groups: group 1 (Fagales pollen allergy without OAS), group 2 (Fagales pollen allergy with OAS), group 3 (OAS with peanut anaphylaxis), and group 4 (peanut anaphylaxis).

RESULTS

After peanut consumption, one-third of OAS patients experienced oral symptoms not associated with peanut sensitization. Ara h 1 or Ara h 2 was positive in peanut anaphylaxis patients, whereas Ara h 8 was positive in OAS patients. There were 4 patients with both peanut anaphylaxis and OAS (group 3). Both Ara h 2 and Ara h 8 were positive in these patients. Foods associated with OAS in Korea showed unique patterns compared to Westernized countries.

CONCLUSIONS

Ara h 2 and Ara h 8 may be important component allergens for discriminating peanut allergy.

Disclosing food allergy status in schools: health-related stigma among school children in Ontario

In 2006, 3 years after the tragic death of 13-year-old Sabrina Shannon, the Province of Ontario (Canada) passed Sabrina's Law ushering in a new era of focus and concern for severe food allergic children at risk of anaphylaxis. Questions were raised at the time regarding the potential of doing more harm than good with the new legislation. This paper reports the experiences of health-related stigma among food allergic children at risk of anaphylaxis who were required to disclose their health status under this new legislation. In 2008, in-depth interviews were conducted with 20 children and youth and their parents in order to explore the experiences living with a severe food allergy. This particular study explores their experiences of felt and enacted stigma in the school setting as a result of the disclosure process. Interviews were tape recorded with permission and transcribed for subsequent thematic analysis using NVIVO, a qualitative analysis software package. Results indicate that participants were stigmatised as a result of protective school policies under the law, and that created tension between their physical safety and social well-being. Sabrina's Law also led to a cultural shift in awareness of food allergies that resulted in some participants normalising their health status, offering promising directions for the future.