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Background: Although previous single-center studies report the rate of anaphylaxis for oral food challenges (OFCs) as 9% to 11%, little is known regarding the epidemiology of clinical OFCs across multiple centers in the United States., Objective: To examine the epidemiology, symptoms, and treatment of clinical low-risk OFCs in the nonresearch setting., Methods: Data were obtained from 2008 to 2013 through a physician survey in 5 food allergy centers geographically distributed across the United States. Allergic reaction rates and the association of reaction rates with year, hospital, and demographics were determined using a linear mixed model. Meta-analysis was used to pool the proportion of reactions and anaphylaxis with inverse-variance weights using a random-effects model with exact confidence intervals (CIs)., Results: A total of 6,377 OFCs were performed, and the pooled estimate of anaphylaxis was 2% (95% CI, 1%-3%). The rate of allergic reactions was 14% (95% CI, 13%-16%) and was consistent during the study period (P = .40). Reaction rates ranged from 13% to 33%. Males reacted 16% more frequently than females (95% CI, 4%-37.5%; P = .04). Foods challenged in 2013 varied geographically, with peanut as the most challenged food in the Northeast, Midwest, and West and egg as the most challenged in the South., Conclusion: As the largest national survey of allergic reactions of clinical open OFCs in a nonresearch setting in the United States, this study found that performing clinical nonresearch open low-risk OFCs results in few allergic reactions, with 86% of challenges resulting in no reactions and 98% without anaphylaxis., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Antibodies are used extensively in numerous applications both in vivo and in vitro. To purify anti-Ara h 2 polyclonal antibody, a homemade immunoaffinity chromatography (IAC) column method was established. The properties of homemade column were compared with those of the mAb affinity protein G (MPG) agarose high flow, a commercially available column successfully used in capturing polyclonal antibodies. During antibody purification from rabbits' antiserum against Ara h 2, the column capacity, recovery, and purification factor were characterized for IAC and MPG. The homemade IAC could separate the corresponding antibody with higher specificity and lower cost but with lower recovery and column capacity than those of MPG. Thus, the homemade IAC is a specific, inexpensive, and suitable method that can be used for various laboratory purifications.

Background: Measurement of IgE antibody to peanut components can aid in the prediction of allergic responses the food., Objective: To investigate the association between patient demographics (age, location) and allergic sensitization to peanut components across the United States., Methods: Serum samples from 12,155 individuals with peanut extract specific IgE levels of 0.35 kUA/L or higher were analyzed for IgE antibodies to Ara h 1, 2, 3, 8, and 9 by ImmunoCAP., Results: Among this population of peanut sensitized individuals, 79.1% of children (<3 years old) were sensitized to one or more peanut storage proteins (Ara h 1, 2, and/or 3), in contrast to 64.2% of adolescents (12-15 years old) and 22.1% of adults (>20 years old). Although sensitization was more prevalent to Ara h 2 than to the other storage proteins, a sizable fraction of patients were sensitized to Ara h 1 and/or 3 but not to Ara h 2 (eg, 13% of children <3 years old). Moreover, 9.6% of children, 10.2% of adolescents, and 10.5% of adults were sensitized to Ara h 9, whereas 2.4% of children, 49.4% of adolescents, and 42.9% of adults produced IgE to Ara h 8 (pathogenesis-related protein 10). Sensitization to Ara h 8 alone was markedly higher in the Northeastern United States relative to other regions of the country., Conclusion: We conclude that sensitization to individual peanut components is highly dependent on age and geographic location. Given that a severe allergic reaction to peanut is unlikely in individuals with isolated sensitization to Ara h 8, a sizable fraction of patients, in particular adolescents and adults, may be at lower risk than anticipated based only on demonstration of sensitization to whole peanut extract., (Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.)

Background: Peripheral blood mononuclear cells (PBMCs) proliferate inconsistently, rendering current lymphoproliferation assays unreliable in diagnosis., Objective: To investigate the utility and nature of proliferation responses in allergy by comparison of the standard lymphoproliferation with a new dendritic cell (DC) stimulated assay., Methods: Monocyte-derived DCs were pulsed with allergens and incubated with autologous T cells for 7 days. DC-stimulated and standard PBMC proliferation responses to 3 common dietary allergens in children with allergy and without atopy were measured by incorporation of tritiated thymidine and reduction of carboxyl fluorescein succinimidyl ester staining., Results: The DC presentation of sensitizing allergens induced significantly higher proliferative responses than PBMC stimulation (P = .04) and greater distinction between normal and allergic responses. DC-induced stimulation indices of children without sensitivity and those with allergy were significantly different with all 3 foods (P < .001). All children with allergy presented with peanut allergy and 12 of 14 (86%) β-lactoglobulin-pulsed DC preparations proliferated more than 3.3-fold above un-pulsed cells, but 8 of 18 children (44%) with ovalbumin egg allergy showed proliferation below this level. The stimulation index of DC tritiated thymidine incorporation correlated closely with carboxyl fluorescein succinimidyl ester reduction (P < .001). Sensitivity of detection of peanut, milk, or egg allergy was 100%, 85.7%, or 55.6% and specificity was 60%, 88.9%, or 86.7%, respectively. DC-stimulated T cells expressed increased levels of CD45 RO and CD25 and most produced interferon-γ. DC-stimulated proliferation correlated with total immunoglobulin E and peanut antigen-stimulated proliferation correlated with peanut specific immunoglobulin E (P = .03)., Conclusion: The DC-induced lymphoproliferation had higher sensitivity, specificity, and reproducibility than the standard assay and caused increased memory and activated T-cell proliferation in children with food allergy., (Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: The relationship between anaphylaxis and cardiovascular events has been reported in the past. While skin and respiratory symptoms are usually the most common and the first to appear, cardiovascular complications play a key role and represent the leading cause of death in anaphylaxis., Methods: We report 3 episodes of atrial fibrillation triggered by anaphylaxis. Allergy and cardiology studies were performed. In both patients, the etiological agent was identified: Anisakis simplex hypersensitivity and food allergy., Results: The heart is the source and target of chemical mediators released during an allergic reaction. In the heart, there are plenty of mast cells, and they are predominantly located around the coronary adventitia and in close contact with small vessels in the muscle wall. The release of mediators can influence ventricular function, heart rate, and coronary artery tone. Anaphylaxis can trigger any kind of arrhythmia. In these cases, the very interesting point of discussion was: which should be first, treating anaphylaxis or cardiac events? The other controversial point was the use of epinephrine, the first line of treatment for anaphylaxis. Recommendations about epinephrine in cardiac patients during an anaphylactic event are still a major dilemma., Conclusions: We emphasize the importance of the priority of establishing protocols between cardiologist and allergist in treatment of cardiac complications during anaphylaxis, and we warn about the correct diagnosis of arrhythmias in anaphylaxis in order to treat them as soon as possible, to prevent other consequences and complications., (Copyright © 2017 Elsevier Inc. All rights reserved.)

Stability to proteolytic degradation in the digestive tract is considered a general feature shared by most food allergens. Current digestibility models exclusively utilize purified allergen proteins, neglecting the relevant effects of matrix that occur for foodstuff systems. In the present study, we investigated digestion stability of the major peanut allergens directly in the natural matrix using an in vitro static model that simulates the gastrointestinal digestion including the oral, gastric, duodenal and intestinal (brush border membrane enzymes) phases. Immunogenicity was evaluated by Western Blot using N=8 pooled sera of peanut allergic pediatric subjects. Immunoreactive, large-sized and fragments of Ara h 2, Ara h 6 and Ara h 3 survived hydrolysis as assessed by SDS-PAGE. Smaller resistant peptides mainly arising from Ara h 3 and also Ara h 1 were detected and further identified by LC-high resolution-MS/MS. RP-HPLC purification followed by dot-blot analysis and MS/MS-based identification demonstrated that stable IgE-binding peptides derived from Ara h 3. These results provide a more realistic picture of the potentially allergenic determinants of peanuts that survived the human digestion, taking into account the role of the food matrix, which may significantly affect gastrointestinal breakdown of peanut allergens., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Aflatoxin contamination, caused by fungal pathogen Aspergillus flavus, is a major quality and health problem delimiting the trade and consumption of groundnut (Arachis hypogaea L.) worldwide. RNA-seq approach was deployed to understand the host-pathogen interaction by identifying differentially expressed genes (DEGs) for resistance to in-vitro seed colonization (IVSC) at four critical stages after inoculation in J 11 (resistant) and JL 24 (susceptible) genotypes of groundnut. About 1,344.04 million sequencing reads have been generated from sixteen libraries representing four stages in control and infected conditions. About 64% and 67% of quality filtered reads (1,148.09 million) were mapped onto A (A. duranensis) and B (A. ipaёnsis) subgenomes of groundnut respectively. About 101 million unaligned reads each from J 11 and JL 24 were used to map onto A. flavus genome. As a result, 4,445 DEGs including defense-related genes like senescence-associated proteins, resveratrol synthase, 9s-lipoxygenase, pathogenesis-related proteins were identified. In A. flavus, about 578 DEGs coding for growth and development of fungus, aflatoxin biosynthesis, binding, transport, and signaling were identified in compatible interaction. Besides identifying candidate genes for IVSC resistance in groundnut, the study identified the genes involved in host-pathogen cross-talks and markers that can be used in breeding resistant varieties.

Introduction: Different clinical and molecular patterns of food allergy have been reported in different areas of the world. The aim of the study is to evaluate differences in allergen patterns among nut-allergic patients in two different areas of Spain., Material and Methods: A total of 77 patients with nut allergy from two different regions of Spain (Madrid and Asturias) were evaluated., Results: Hazelnut, peanut, and walnut were the three most frequent nuts eliciting allergy in both regions, but in a different order. Patients from Madrid experienced systemic reactions more often than patients from Asturias (73.5% Madrid vs. 50.0%, p < 0.05). The percentage of sensitizations to LTP (Lipid Transfer Protein) was higher than Bet v 1 ( p < 0.05) in the Madrid area. The percentage of sensitizations in Asturias area was similar to LTP than Bet v 1 (Pru p 3 46.4%, Bet v 1 42.9%, ns). Bet v 1 was the predominant allergen involved among hazelnut-allergic patients (56.2%), while LTP was more common in peanut-allergic patients (61.5%)., Conclusion: Walnut, hazelnut, and peanut were the most frequent nuts eliciting allergy in Spain. Despite this, important differences in molecular pattern were appreciated not only between both regions, but also among nut-allergic patients in Asturias. The different molecular pattern was linked to the frequency of systemic symptoms., Competing Interests: The authors declare no conflict of interest. The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Allergy to peanuts has become a common and severe problem, especially in westernized countries. In this study, we evaluated the target and epitope specificity of the capture and detection mouse monoclonal antibodies (mAbs) used in a commercial peanut allergen detection platform. We first identified the target of these antibodies as Ara h 3 and then used an overlapping peptide array of Ara h 3 to determine the antibody-binding epitopes. Further amino acids critical for the binding via alanine substitutions at individual amino acid residues within the epitope were mapped. Finally, inhibition ELISA and inhibition immunoblotting using a recombinant Ara h 3 protein were performed to confirm these results. Surprisingly, the capture and detection mAbs showed identical binding characteristics and were presumed to represent two isolates of the same clone, a notion supported by both isoelectric focusing electrophoresis and Liquid chromatography-mass spectrometry experiments. The simultaneous binding of a pair of identical mAbs to an individual allergen such as Ara h3 is attributed to the multivalency of the analyte and has implications for developing diagnostic assays for additional multimeric allergens.

Allergen-specific type 2 helper T (T H 2) cells play a central role in initiating and orchestrating the allergic and asthmatic inflammatory response pathways. One major factor limiting the use of such atopic disease-causing T cells as both therapeutic targets and clinically useful biomarkers is the lack of an accepted methodology to identify and differentiate these cells from overall nonpathogenic T H 2 cell types. We have described a subset of human memory T H 2 cells confined to atopic individuals that includes all allergen-specific T H 2 cells. These cells are terminally differentiated CD4 + T cells (CD27 - and CD45RB - ) characterized by coexpression of CRT H 2, CD49d, and CD161 and exhibit numerous functional attributes distinct from conventional T H 2 cells. Hence, we have denoted these cells with this stable allergic disease-related phenotype as the T H 2A cell subset. Transcriptome analysis further revealed a distinct pathway in the initiation of pathogenic responses to allergen, and elimination of these cells is indicative of clinical responses induced by immunotherapy. Together, these findings identify a human T H 2 cell signature in allergic diseases that could be used for response-monitoring and designing appropriate immunomodulatory strategies., (Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

Refined vegetable oils including refined peanut oil are widely used in foods. Due to shared production processes, refined non-peanut vegetable oils can contain residual peanut proteins. We estimated the predicted number of allergic reactions to residual peanut proteins using probabilistic risk assessment applied to several scenarios involving food products made with vegetable oils. Variables considered were: a) the estimated production scale of refined peanut oil, b) estimated cross-contact between refined vegetable oils during production, c) the proportion of fat in representative food products and d) the peanut protein concentration in refined peanut oil. For all products examined the predicted risk of objective allergic reactions in peanut-allergic users of the food products was extremely low. The number of predicted reactions ranged depending on the model from a high of 3 per 1000 eating occasions (Weibull) to no reactions (LogNormal). Significantly, all reactions were predicted for allergen intakes well below the amounts reported for the most sensitive individual described in the clinical literature. We conclude that the health risk from cross-contact between vegetable oils and refined peanut oil is negligible. None of the food products would warrant precautionary labelling for peanut according to the VITAL ® programme of the Allergen Bureau., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Background: In the Learning Early About Peanut Allergy (LEAP) study, early peanut introduction in high-risk 4- to 11-month-olds was associated with a significantly decreased risk of developing peanut allergy. However, the influences of key baseline high-risk factors on peanut tolerance are poorly understood., Methods: Secondary analysis was conducted on the publically available LEAP dataset, exploring relationships between peanut tolerance, baseline peanut/egg sensitization, eczema severity/duration, age of introduction, gender, and race., Results: A multiple logistic regression model predicting odds of successful oral food challenge (OFC) at 60 months noted higher odds with early introduction (OR 9.2, P < 0.001, 95% CI 4.2-20.3), white race (OR 2.1, P = 0.04, 95% CI 1.1-3.9), and advancing age (OR 4.8, P = 0.04, 95% CI 1.1-20.8). Odds of peanut tolerance were lower with increasing peanut wheal size (OR 0.58, P < 0.001, 95% CI 0.46-0.74), increased baseline SCORAD score (OR 0.98, P = 0.04, 95% CI 0.97-1), and increased kU A /l of egg serum IgE (sIgE) (OR 0.99, P = 0.04, 95% CI 0.98-1). The probability of peanut tolerance in the early introduction group was 83% vs 43% in the avoidance group with SPT wheal of <4 mm. The probability of a successful OFC was significantly higher with peanut introduction between 6 and 11 months than at 4-6 months. Increasing eczema severity had limited impact on the probability of peanut tolerance in the early introduction arm., Conclusion: Increasing peanut wheal size predicted peanut tolerance only in the avoidance arm. Peanut introduction between 6 and 11 months of age was associated with the highest rates of peanut tolerance, questioning the 'urgency' of introduction before 6 months., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Many food experts have studied various treatments or processing techniques in order to develop hypoallergenic foods. In a previous study, acid treatment dramatically mitigated the allergenicity of peanut, especially Ara h 2., Results: Gel electrophoresis showed that most protein bands of acid-treated peanut were not detected, but protein bands of egg white became weaker and broader by acid treatment. In immunoblotting using a rabbit antibody, the antigenicity against ovalbumin or ovomucoid in acid-treated egg white was decreased but the antigenicity against Ara h 1 or Ara h 2 in peanut treated with pH 2 acetic acid was completely undetected. The allergenicity of ovalbumin and peanut fell significantly to 1/10 22 and 1/5380, respectively, when measured as IC 50 in the sample treated with pH 2.0 acetic acid., Conclusion: This study showed that acid treatment was more effective in peanut and barely effective in ovomucoid. This may contribute to the development of hypoallergenic food and clinical management of food allergy. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)

Background: Approximately 1% of the U.S. population has a peanut allergy. Previous studies that measured peanut protein in house dust support the hypothesis that household peanut consumption may lead to clinical sensitization through transdermal exposure., Objective: The aim of this pilot study was to characterize Ara h2 levels in house dust from homes with and without individuals with peanut allergy., Methods: Household dust was obtained from homes with an individual with peanut allergy and from homes with no individual with peanut allergy. Ara h2 levels were determined by using a monoclonal antibody-based immunoassay with a level of determination of 150 ng per gram of dust. Peanut consumption information was obtained by questionnaire., Results: A total of 85 dust samples were collected: 38 from homes with a individual with peanut allergy and 47 from control homes. The median Ara h2 level in homes with an individual with peanut allergy was 1236 ng/g (interquartile range [IQR], 256-1342 ng/g), whereas the median Ara h2 level in homes without an individual with peanut allergy was 650 ng/g (IQR, 163-2201 ng/g). Ara h2 levels in dust from homes of individuals with peanut allergy were not significantly lower than in dust from control homes. Of the homes with an individual with peanut allergy, 15 reported complete avoidance of peanut in the home (39%). Ara h2 levels in homes that completely avoided peanuts were not significantly lower than Ara h2 levels in homes that did not restrict peanuts (p = 0.531)., Conclusion: Although families may restrict peanuts and peanut products in the home, there was still detectable Ara h2 levels found in homes. Each subject's definition of restriction may vary, there seemed to be peanut protein entering the home, although the protein origin is not known. Possibilities include cross-reactivity with another antigen or transport into the home on some vector. Further investigation of hypotheses regarding cross-reactivity and environmental exposure to Ara h2 is necessary.

Background: Anaphylaxis is a life-threatening condition for which we have limited therapeutic options. Although specific immunotherapy for food allergies is becoming more effective, it is still laborious and carries substantial risk of adverse events. On the other hand, regulatory dendritic cell (DC) therapy is effective in mouse models of allergic disease and has been shown to work with T H 2 cells from atopic asthmatic patients., Objective: We assessed whether DC immunotherapy could reverse food allergen sensitivity in mouse models to provide proof of concept relating to their use in the clinic., Methods: We generated and characterized mature retinoic acid-skewed dendritic cells (DC-RAs) and assessed their abilities to reverse ovalbumin or peanut allergies in mouse models, as well as their operative mechanisms., Results: DC-RAs displayed a mature yet tolerogenic phenotype, expressing IL-10, TGF-β, IL-27, and aldehyde dehydrogenase 1A2 but not IL-12 or IL-35; IL-10 and TGF-β together drove their suppression of T H 2 cell proliferation. Delivery of specific allergen-presenting DC-RAs to half-maximally sensitized mice with ovalbumin or peanut allergy reduced anaphylactic responses to oral allergen challenge by 84% to 90%, as well as diarrhea, mast cell activation, and T H 2 cytokine responses and serum allergen-specific IgE/IgG 1 levels. DC-RA expression of IL-27 was important to their induction of CD25 + lymphocyte activation gene 3 (LAG3) + , CD49b - , forkhead box P3 (Foxp3) - regulatory T cells in vitro, such that β subunit of IL-27 (Ebi) -/- (ie, IL-27-incompetent) DC-RAs were ineffective in inducing food allergen tolerance., Conclusion: Our data indicate that regulatory DC immunotherapy can be effective for food allergies and suggest that induction of Foxp3 - regulatory T cells might be a useful strategy for tolerance induction in this context., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: Peanut allergy in children is often associated with allergies to tree nuts and/or legumes. The aim of this study was to analyze in cluster a cohort of children allergic to peanuts and assessed for cross-reactivity to nuts and legumes and to identify different phenotypes., Methods: We included retrospectively 317 children with peanut allergy evaluated at the Allergy Unit of the Saint Vincent Hospital of Lille in the last 12 years. A complete workup for peanut allergy and nuts and legumes was carried out for each patient. A hierarchical agglomerative clustering method was used to search for clusters of individuals in the evaluated cohort., Results: Cross-allergy to TN and/or other legumes was identified in 137 patients (43.2%), atopic dermatitis being a major risk factor (adjusted OR = 16 [95% CI: 7.4-37]; p < 0.001). Three phenotypes emerged from cluster analysis. Cluster 1 (72 patients) is characterized by high level of rAra h 2, low threshold reactive doses for peanut and high proportion of asthma; Cluster 2 (93 patients) is characterized by high threshold reactive doses for peanut and the lowest proportion of cross-allergy to TN and/or legumes; Cluster 3 (152 patients) has a high risk of cross-allergy to TN and/or legumes and most patients suffer from eczema., Conclusions: The three phenotypes highlighted by this study could be useful to identify children with high risk of cross-allergic reaction to TNs and legumes early after PA diagnosis., (© 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Background: Eliciting doses (EDs) of allergenic foods can be defined by the distribution of threshold doses for subjects within a specific population. The ED 05 is the dose that elicits a reaction in 5% of allergic subjects. The predicted ED 05 for peanut is 1.5 mg of peanut protein (6 mg of whole peanut)., Objective: We sought to validate the predicted peanut ED 05 (1.5 mg) with a novel single-dose challenge., Methods: Consecutive eligible children with peanut allergy in 3 centers were prospectively invited to participate, irrespective of previous reaction severity. Predetermined criteria for objective reactions were used to identify ED 05 single-dose reactors., Results: Five hundred eighteen children (mean age, 6.8 years) were eligible. No significant demographic or clinical differences were identified between 381 (74%) participants and 137 (26%) nonparticipants or between subjects recruited at each center. Three hundred seventy-eight children (206 male) completed the study. Almost half the group reported ignoring precautionary allergen labeling. Two hundred forty-five (65%) children experienced no reaction to the single dose of peanut. Sixty-seven (18%) children reported a subjective reaction without objective findings. Fifty-eight (15%) children experienced signs of a mild and transient nature that did not meet the predetermined criteria. Only 8 (2.1%; 95% CI, 0.6%-3.4%) subjects met the predetermined criteria for an objective and likely related event. No child experienced more than a mild reaction, 4 of the 8 received oral antihistamines only, and none received epinephrine. Food allergy-related quality of life improved from baseline to 1 month after challenge regardless of outcome (η 2  = 0.2, P < .0001). Peanut skin prick test responses and peanut- and Ara h 2-specific IgE levels were not associated with objective reactivity to peanut ED 05 ., Conclusion: A single administration of 1.5 mg of peanut protein elicited objective reactions in fewer than the predicted 5% of patients with peanut allergy. The novel single-dose oral food challenge appears clinically safe and patient acceptable, regardless of the outcome. It identifies the most highly dose-sensitive population with food allergy not otherwise identifiable by using routinely available peanut skin prick test responses or specific IgE levels, but this single-dose approach has not yet been validated for risk assessment of individual patients., (Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Peanut allergy is a worldwide health concern. In this study, the natural binding properties of plant-derived polyphenols to proteins was leveraged to produce stable protein-polyphenol complexes comprised of peanut proteins and cranberry (Vaccinium macrocarpon Ait.) or lowbush blueberry (Vaccinium angustifolium Ait.) pomace polyphenols. Protein-bound and free polyphenols were characterized and quantified by multistep extraction of polyphenols from protein-polyphenol complexes. Immunoblotting was performed with peanut-allergic plasma to determine peanut protein-specific IgE binding to unmodified peanut protein, or to peanut protein-polyphenol complexes. In an allergen model system, RBL-2H3 mast cells were exposed to peanut protein-polyphenol complexes and evaluated for their inhibitory activity on ionomycin-induced degranulation (β-hexosaminidase and histamine). Among the evaluated polyphenolic compounds from protein-polyphenol complex eluates, quercetin, - in aglycone or glycosidic form - was the main phytochemical identified to be covalently bound to peanut proteins. Peanut protein-bound cranberry and blueberry polyphenols significantly decreased IgE binding to peanut proteins at p < 0.05 (38% and 31% decrease, respectively). Sensitized RBL-2H3 cells challenged with antigen and ionomycin in the presence of protein-cranberry and blueberry polyphenol complexes showed a significant (p < 0.05) reduction in histamine and β-hexosaminidase release (histamine: 65.5% and 65.8% decrease; β-hexosaminidase: 60.7% and 45.4% decrease, respectively). The modification of peanut proteins with cranberry or blueberry polyphenols led to the formation of peanut protein-polyphenol complexes with significantly reduced allergenic potential. Future trials are warranted to investigate the immunomodulatory mechanisms of these protein-polyphenol complexes and the role of quercetin in their hypoallergenic potential.

Peanut is a major oilseed crop worldwide. In the Brazilian peanut production, silvering thrips and red necked peanut worm are the most threatening pests. Resistant varieties are considered an alternative to pest control. Many wild diploid Arachis species have shown resistance to these pests, and these can be used in peanut breeding by obtaining hybrid of A and B genomes and subsequent polyploidization with colchicine, resulting in an AABB amphidiploid. This amphidiploid can be crossed with cultivated peanut (AABB) to provide genes of interest to the cultivar. In this study, the sterile diploid hybrids from A. magna V 13751 and A. kempff-mercadoi V 13250 were treated with colchicine for polyploidization, and the amphidiploids were crossed with A. hypogaea cv. IAC OL 4 to initiate the introgression of the wild genes into the cultivated peanut. The confirmation of the hybridity of the progenies was obtained by: (1) reproductive characterization through viability of pollen, (2) molecular characterization using microsatellite markers and (3) morphological characterization using 61 morphological traits with principal component analysis. The diploid hybrid individual was polyploidized, generating the amphidiploid An 13 (A. magna V 13751 x A. kempff-mercadoi V 13250)4x. Four F1 hybrid plants were obtained from IAC OL 4 × An 13, and 51 F2 seeds were obtained from these F1 plants. Using reproductive, molecular and morphological characterizations, it was possible to distinguish hybrid plants from selfed plants. In the cross between A. hypogaea and the amphidiploid, as the two parents are polyploid, the hybrid progeny and selves had the viability of the pollen grains as high as the parents. This fact turns the use of reproductive characteristics impossible for discriminating, in this case, the hybrid individuals from selfing. The hybrids between A. hypogaea and An 13 will be used in breeding programs seeking pest resistance, being subjected to successive backcrosses until recovering all traits of interest of A. hypogaea, keeping the pest resistance.

Significant efforts are being made to minimize aflatoxin contamination in peanut seeds and one possible strategy is to understand and exploit the mechanisms of plant defense against fungal infection. In this study we have identified and characterized, at biochemical and molecular levels, plant protease inhibitors (PPIs) produced in peanut seeds of the resistant PI 337394 and the susceptible Forman cultivar during Aspergillus parasiticus colonization. With chromatographic methods and 2D-electrophoresis-mass spectrometry we have isolated and identified four variants of Bowman-Birk trypsin inhibitor (BBTI) and a novel Kunitz-type protease inhibitor (KPI) produced in response to A. parasiticus colonization. KPI was detected only in the resistant cultivar, while BBTI was produced in the resistant cultivar in a higher concentration than susceptible cultivar and with different isoforms. The kinetic expression of KPI and BBTI genes along with trypsin inhibitory activity was analyzed in both cultivars during infection. In the susceptible cultivar an early PPI activity response was associated with BBTI occurrence. Meanwhile, in the resistant cultivar a later response with a larger increase in PPI activity was associated with BBTI and KPI occurrence. The biological significance of PPI in seed defense against fungal infection was analyzed and linked to inhibitory properties on enzymes released by the fungus during infection, and to the antifungal effect of KPI.

Synergism between beneficial rhizobacteria and fungal pathogens is poorly understood. Therefore, evaluation of co-inoculation of bacteria that promote plant growth by different mechanisms in pathogen challenged plants would contribute to increase the knowledge about how plants manage interactions with different microorganisms. The goals of this work were a) to elucidate, in greenhouse experiments, the effect of co-inoculation of peanut with Bradyrhizobium sp. SEMIA6144 and the biocontrol agent Bacillus sp. CHEP5 on growth and symbiotic performance of Sclerotium rolfsii challenged plants, and b) to evaluate field performance of these bacteria in co-inoculated peanut plants. The capacity of Bacillus sp. CHEP5 to induce systemic resistance against S. rolfsii was not affected by the inoculation of Bradyrhizobium sp. SEMIA6144. This microsymbiont, protected peanut plants from the S. rolfsii detrimental effect, reducing the stem wilt incidence. However, disease incidence in plants inoculated with the isogenic mutant Bradyrhizobium sp. SEMIA6144 V2 (unable to produce Nod factors) was as high as in pathogen challenged plants. Therefore, Bradyrhizobium sp. SEMIA6144 Nod factors play a role in the systemic resistance against S. rolfsii. Bacillus sp. CHEP5 enhanced Bradyrhizobium sp. SEMIA6144 root surface colonization and improved its symbiotic behavior, even in S. rolfsii challenged plants. Results of field trials confirmed the Bacillus sp. CHEP5 ability to protect against fungal pathogens and to improve the yield of extra-large peanut seeds from 2.15% (in Río Cuarto) to 16.69% (in Las Vertientes), indicating that co-inoculation of beneficial rhizobacteria could be a useful strategy for the peanut production under sustainable agriculture system., (Copyright © 2017 Elsevier GmbH. All rights reserved.)

The antigenic reactivity of constituents of Schistosoma mansoni and peanut (Arachis hypogaea) was investigated to determine whether identical antigenic epitopes possessed by both organisms provided a possible explanation for the negative correlation between chronic schistosome infection and atopy to allergens. Aqueous extracts of peanuts were probed in Western immunoblots with rabbit IgG antibodies raised against the egg, cercarial and adult worm stages of S. mansoni. Several molecules in the peanut extract were antigenically reactive with antibodies from the various rabbit anti-schistosome sera. A pair of cross-reactive peanut molecules at ~30 000-33 000 molecular weight was purified and both proteins were identified by mass spectrometric analysis as the peanut allergen Ara h 1. Anti-S. mansoni soluble egg antigen antibodies that were eluted off the peanut molecules reacted with two S. mansoni egg antigens identified by mass spectrometry as IPSE/α-1 and κ-5. Alignments of the amino acid sequences of Ara h 1 and either IPSE/α-1 or κ-5 revealed a low level of peptide sequence identity. Incubation of nitrocellulose paper carrying electrophoresed peanut molecules, six constituents of other allergic plants and S. mansoni egg antigens in a mild solution of sodium metaperiodate before probing with antibodies, inhibited most of the cross-reactivities. The results are consistent with the antigenic cross-reactive epitopes of S. mansoni egg antigens, peanut and other allergic plants being cross-reactive carbohydrate determinants (CCDs). These findings are novel and an explanation based on 'blocking antibodies' could provide an insight for the inverse relationship observed between schistosome infection and allergies., (© 2017 John Wiley & Sons Ltd.)

Background: Treatment with omalizumab has shown a positive effect on food allergies, but no dosages are established. Basophil allergen threshold sensitivity (CD-sens) can be used to objectively measure omalizumab treatment efficacy and correlates with the outcome of double-blind placebo-controlled food challenge to peanut., Objective: To evaluate whether individualized omalizumab treatment monitored by CD-sens could be an effective intervention for suppression of allergic reactions to peanut., Methods: Severely peanut allergic adolescents (n = 23) were treated with omalizumab for 8 weeks, and CD-sens was analysed before and after. Based on whether CD-sens was suppressed after 8 weeks, the patients either were subject to a peanut challenge or received eight more weeks with increased dose of omalizumab, followed by peanut challenge or another 8-week cycle of omalizumab. IgE and IgE-antibodies to peanut and its components were analysed before treatment., Results: After individualized omalizumab treatment (8-24 weeks), all patients continued with an open peanut challenge with no (n = 18) or mild (n = 5) objective allergic symptoms. Patients (n = 15) needing an elevated omalizumab dose (ED) to suppress CD-sens had significantly higher CD-sens values at baseline 1.49 (0.44-20.5) compared to those (n = 8) who managed with normal dose (ND) 0.32 (0.24-5.5) (P < 0.01). Median ratios for Ara h 2 IgE-ab/IgE were significantly higher in the ED group (17%) compared to the ND group (11%)., Conclusions and Clinical Relevance: Individually dosed omalizumab, monitored by CD-sens, is an effective and safe treatment for severe peanut allergy. The ratio of IgE-ab to storage protein Ara h 2/IgE as well as CD-sens to peanut may predict the need of a higher omalizumab dose. Clinical trials numbers: EudraCT; 2012-005625-78, ClinicalTrials.gov; NCT02402231., (© 2016 John Wiley & Sons Ltd.)

Food allergy is estimated to affect approximately 8% of children in the USA. This is a disease without any known treatment or cure and, for some, a disease that can be quite severe, even life-threatening. While recent advances in potential treatment have made remarkable strides, with two food-targeted immunotherapy products now in phase III trials, perhaps the biggest gains in the field have come in the advent of potential preventative strategies to avoid the development of food allergy in high-risk individuals. There have been multiple, randomized, controlled trials (RCTs) performed in the past 5 years that have demonstrated significant risk reduction from early allergen introduction. These include two trials for early peanut introduction and five trials for early egg introduction in the first year of life. The results indicate that primary prevention of food allergy through early allergen introduction may represent a strategy that could potentially avert tens of thousands of children from becoming food allergic. In support of the data for peanut, the National Institute of Allergy and Infectious Diseases recently sponsored an addendum to the 2010 food allergy guidelines, specifically recommending peanut be introduced in both high- and standard-risk infants to reduce the risk of developing peanut allergy. To date, no formal recommendations have been made for egg, however. This review will focus on the latest evidence supporting early introduction as a strategy to prevent food allergy, as well as on practical aspects for its successful implementation.

Background: Peanut oral immunotherapy is a promising approach to peanut allergy, but reactions are frequent, and some patients cannot be desensitized. The anti-IgE medication omalizumab (Xolair; Genentech, South San Francisco, Calif) might allow more rapid peanut updosing and decrease reactions., Objective: We sought to evaluate whether omalizumab facilitated rapid peanut desensitization in highly allergic patients., Methods: Thirty-seven subjects were randomized to omalizumab (n = 29) or placebo (n = 8). After 12 weeks of treatment, subjects underwent a rapid 1-day desensitization of up to 250 mg of peanut protein, followed by weekly increases up to 2000 mg. Omalizumab was then discontinued, and subjects continued on 2000 mg of peanut protein. Subjects underwent an open challenge to 4000 mg of peanut protein 12 weeks after stopping study drug. If tolerated, subjects continued on 4000 mg of peanut protein daily., Results: The median peanut dose tolerated on the initial desensitization day was 250 mg for omalizumab-treated subjects versus 22.5 mg for placebo-treated subject. Subsequently, 23 (79%) of 29 subjects randomized to omalizumab tolerated 2000 mg of peanut protein 6 weeks after stopping omalizumab versus 1 (12%) of 8 receiving placebo (P < .01). Twenty-three subjects receiving omalizumab versus 1 subject receiving placebo passed the 4000-mg food challenge. Overall reaction rates were not significantly lower in omalizumab-treated versus placebo-treated subjects (odds ratio, 0.57; P = .15), although omalizumab-treated subjects were exposed to much higher peanut doses., Conclusion: Omalizumab allows subjects with peanut allergy to be rapidly desensitized over as little as 8 weeks of peanut oral immunotherapy. In the majority of subjects, this desensitization is sustained after omalizumab is discontinued. Additional studies will help clarify which patients would benefit most from this approach., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Results from the Learning Early About Peanut trial and its follow-up study suggest that early peanut introduction in the diets of high-risk infants may prevent the development of peanut allergy. Allergy organizations around the world released a unified statement, the Consensus Communication on Early Peanut Introduction and the Prevention of Peanut Allergy in High Risk Infants, in response to results from the Learning Early About Peanut trial, which recommends early introduction of peanut into the diet of those children at greatest risk of development of peanut allergy. As a result, it is expected that practicing allergists will experience an increased demand to perform an oral food challenge (OFC) in infants. Allergists often perform OFCs; however, conducting an OFC in an infant creates unique circumstances that have not been considered in previously published OFC guideline documents. The purpose of this workgroup report is to provide guidance to practitioners regarding the proper approach for conducting a peanut challenge in an infant., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

The extraction of Ara h 6 (a peanut allergen) from a complex chocolate-based food matrix was optimized by testing different temperatures, extraction times, and the influence of additives (NaCl and skimmed milk powder) in a total of 36 different conditions. Analyses were carried out using an electrochemical immunosensor. Three conditions were selected since they allowed the extraction of the highest levels of Ara h 6. These extractions were performed using 2g of sample and 20ml of Tris-HNO 3 (pH=8) containing: a) 0.1M NaCl and 2g of skimmed milk powder at 21°C for 60min; b) 1M NaCl and 1g of skimmed milk powder at 21°C for 60min; and c) 2g of skimmed milk powder at 60°C for 60min. Recoveries were similar or higher than 94.7%. This work highlights the importance to adjust extraction procedures regarding the target analyte and food matrix components., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Background: Oral food challenge is the main tool for diagnosing food allergy, but there is little data on the reaction profiles of young children undergoing challenges, nor how these reactions compare to reactions on accidental ingestion in the community., Objectives: To compare reaction profiles from food challenges and parent-reported reactions on accidental ingestion, and assess predictors of severe reactions., Methods: HealthNuts is a longitudinal population-based cohort study of 5276 1-year-old infants. Infants underwent skin prick tests and those with identifiable wheals were offered food challenges. Food challenges were repeated at age 4 years in those with previous food allergy or reporting new food allergies. Community-reported reactions were ascertained from parent questionnaires., Results: Food challenges were undertaken in 916 children at age 1 year and 357 children at age 4 years (a total of 2047 peanut, egg, or sesame challenges). Urticaria was the most common sign in positive challenges at both ages (age 1 year, 88.7%, and age 4 years, 71.2%) although angioedema was significantly more common at age 4 years (40.1%) than at age 1 year (12.9%). Anaphylaxis was equally uncommon at both ages (2.1% and 2.8% of positive challenges at ages 1 and 4 years, respectively) but more common for peanut than for egg (4.5% and 1.2% of positive challenges at ages 1 and 4 years, respectively). The patterns of presenting signs reported during community reactions were similar to those observed in formal food challenges. Serum food-specific IgE levels of 15 kU/L or more were associated with moderate to severe reactions but skin prick test was not., Conclusions: There was a shift from the most common presenting reaction of urticaria during food challenges toward more angioedema in older children. Serum food-specific IgE levels were associated with reaction severity., (Copyright © 2017 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Peanut and tree nut allergies have become a public health problem over the last 2 decades. The diagnostic procedure relies on a suggestive history, as well as on evidence of sensitization (skin prick testing and/or specific IgE blood testing), followed in selected cases by a food challenge. Standard IgE tests may be positive to more than 1 nut, due to cross-reactivity (allergens common to several nuts) or cosensitivity (frequently associated positive test results without cross-reactivity). Thus, many patients with a peanut or a tree nut allergy avoid all nuts, relying on positive test results without clinical evidence of reactivity. In addition, coexisting pollen sensitivity may add to diagnostic uncertainty due to potential cross-reactivity between pollens and nuts. In this article, we discuss challenges in diagnosis and clinical management of peanut and tree nut allergy related to cross-reactivity and cosensitization, as well as the avoidance of nuts tested positive to reduce the risk of reactions by cross-contamination. Studies to provide more accurate characterization of genuine clinically relevant cross-reactivity or cosensitivity to multiple nuts are needed., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. All rights reserved.)

While earlier food allergy prevention strategies implemented avoidance of allergenic foods in infancy, the current paradigm is shifting from avoidance to controlled exposure. This review focuses on the outcome of recent randomized controlled trials, which have examined the early introduction of allergenic foods for allergy prevention, and discusses the implementation of results in clinical practice. In infants at high risk of allergic disease, there is now direct evidence that regular early peanut consumption will reduce the prevalence of peanut allergy, compared to avoidance. Many international infant feeding guidelines already recommend complementary foods, including allergenic foods, to be introduced from 4 to 6 months of age irrespective of family history risk. Interim guidelines from 10 International Pediatric Allergy Associations state that healthcare providers should recommend the introduction of peanut-containing products into the diets of infants at high risk of allergic disease in countries where peanut allergy is prevalent. Direct translation of the results obtained from a cohort of high-risk infants to the general population has proved difficult, and issues regarding feasibility, safety, and cost-effectiveness have been raised. Five randomized placebo-controlled trials have assessed the effects of early egg exposure in infancy with varying results. In a recent comprehensive meta-analysis, there was moderate-certainty evidence that early versus late introduction of egg was associated with a reduced egg allergy risk. Although promising, optimal timing, doses, and if the feeding regimen should be stratified according to infant allergy risk remain to be determined. The single study that assessed introduction of multiple foods from 3 months whilst breastfeeding compared with exclusive breastfeeding until 6 months of age showed no reduction in food allergy prevalence. Future research should aim at optimizing infant feeding regimens and support a tolerogenic gastrointestinal microenvironment during the period of food allergen introduction., (© 2017 S. Karger AG, Basel.)

Background: Oral immunotherapy (OIT) is an effective experimental food allergy treatment that is limited by treatment withdrawal and the frequent reversibility of desensitization if interrupted. Newly diagnosed preschool children may have clinical and immunological characteristics more amenable to treatment., Objective: We sought to test the safety, effectiveness, and feasibility of early OIT (E-OIT) in the treatment of peanut allergy., Methods: We enrolled 40 children aged 9 to 36 months with suspected or known peanut allergy. Qualifying subjects reacted to peanut during an entry food challenge and were block-randomized 1:1 to receive E-OIT at goal maintenance doses of 300 or 3000 mg/d in a double-blinded fashion. The primary end point, sustained unresponsiveness at 4 weeks after stopping early intervention oral immunotherapy (4-SU), was assessed by double-blinded, placebo-controlled food challenge either upon achieving 4 prespecified criteria, or after 3 maintenance years. Peanut-specific immune responses were serially analyzed. Outcomes were compared with 154 matched standard-care controls., Results: Of 40 consented subjects, 3 (7.5%) did not qualify. Overall, 29 of 37 (78%) in the intent-to-treat analysis achieved 4-SU (300-mg arm, 17 of 20 [85%]; 3000 mg, 12 of 17 [71%], P = .43) over a median of 29 months. Per-protocol, the overall proportion achieving 4-SU was 29 of 32 (91%). Peanut-specific IgE levels significantly declined in E-OIT-treated children, who were 19 times more likely to successfully consume dietary peanut than matched standard-care controls, in whom peanut-specific IgE levels significantly increased (relative risk, 19.42; 95% CI, 8.7-43.7; P < .001). Allergic side effects during E-OIT were common but all were mild to moderate., Conclusions: At both doses tested, E-OIT had an acceptable safety profile and was highly successful in rapidly suppressing allergic immune responses and achieving safe dietary reintroduction., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Some studies have suggested that allergens may appear in the circulation after ingestion of allergenic food sources. The reported levels of allergen in serum, however, are low, and conclusions between studies differ. Here, we investigated factors that determine the detection of allergens in serum after consumption of peanuts. Ten healthy volunteers ingested 100g of light-roasted peanuts. Serum samples were taken at regular intervals for six hours. A double monoclonal sandwich ELISA was used to analyse the presence and quantity of the major peanut allergen Ara h 6 in serum. In 4 out of 10 subjects, no Ara h 6 could be detected. Purified Ara h 6 that was digested in vitro was still reactive in the ELISA, rejecting the possibility that digestion leads to small peptides that could not be detected. Spiking of purified Ara h 6 in baseline serum showed that the pre-ingestion serum of these four subjects partially prevented Ara h 6 to react in the ELISA, with a reduction of reactivity of up to 3 orders of magnitude or more. Pre-ingestion serum of the other six subjects did not show such an effect. The reduction of reactivity of Ara h 6 coincided with high titres of IgG and IgG4, and removal of IgG from pre-ingestion serum abolished this effect completely, indicating that IgG and IgG4 inhibited the reactivity of Ara h6 in the ELISA. We conclude that some individuals have IgG and IgG4 against food allergens in their blood, which interferes with detection of such food allergens in serum. Because this effect does not occur for each individual, the possibility of such interference should be taken into consideration when interpreting immunochemical studies on the absorption of food allergens in serum., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Background: The attempt to induce oral tolerance as a treatment for food allergy has been hampered by a lack of sustained clinical protection. Immunotherapy by nonoral routes, such as the skin, may be more effective for the development of maintained tolerance to food allergens., Objective: We sought to determine the efficacy and mechanism of tolerance induced by epicutaneous immunotherapy (EPIT) in a model of food-induced anaphylaxis., Methods: C3H/HeJ mice were sensitized to ovalbumin (OVA) orally or through the skin and treated with EPIT using OVA-Viaskin patches or oral immunotherapy using OVA. Mice were orally challenged with OVA to induce anaphylaxis. Antigen-specific regulatory T (Treg)-cell induction was assessed by flow cytometry using a transgenic T-cell transfer model., Results: By using an adjuvant-free model of food allergy generated by epicutaneous sensitization and reactions triggered by oral allergen challenge, we found that EPIT induced sustained protection against anaphylaxis. We show that the gastrointestinal tract is deficient in de novo generation of Treg cells in allergic mice. This defect was tissue-specific, and epicutaneous application of antigen generated a population of gastrointestinal-homing LAP + Foxp3 - Treg cells. The mechanism of protection was found to be a novel pathway of direct TGF-β-dependent Treg-cell suppression of mast cell activation, in the absence of modulation of T- or B-cell responses., Conclusions: Our data highlight the immune communication between skin and gastrointestinal tract, and identifies novel mechanisms by which epicutaneous tolerance can suppress food-induced anaphylaxis., Competing Interests: Disclosure of potential conflict of interest: LT received travel support from DBV Technologies (the developer and owner of the Viaskin® patch) to present this work in part at the European Academy of Allergy and Clinical Immunology. LM is an employee of DBV Technologies, HAS is the Chief Scientific Officer of DVB Technologies and PHB is CEO of DBV Technologies. MCB has no conflict of interest., (Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.)

Background: Little is known about breast milk as a vehicle for tolerance development or sensitization to peanuts very early in life. Thus, well-characterized and highly sensitive detection systems for the reliable determination of peanut allergens in breast milk are mandatory., Methods: For the quantification of the marker allergens Ara h 2 and Ara h 6 in the low nanogram per milliliter range in breast milk samples of a German cohort, sensitive and highly specific sandwich ELISAs were optimized and validated., Results: The Ara h 2 ELISA revealed a limit of detection (LOD) of 1.3 ng Ara h 2/mL and a quantification range of 2.3-250 ng/mL, the Ara h 6 ELISA showed an LOD of 0.7 ng/mL and a working range of 1.1-14.4 ng/mL. The assays showed no relevant cross-reactivity against other potentially cross-reactive legume, seed, and tree nut extracts (<0.01%, except for Ara h 1 in the Ara h 2 ELISA <0.1%). Ara h 2 was detectable in breast milk samples from 14/40 (35%) of the participants in concentrations from 2.3 to 184 ng/mL, Ara h 6 appeared in 9/40 (22.5%) of the lactating mothers between 1.1 and 9.7 ng/mL, and 1 highly positive sample with 79 ng/mL. Both allergens appeared at the same time points, but Ara h 6 in lower concentrations than Ara h 2., Conclusions: Sensitive and specific diagnostic tools for the determination of Ara h 2 and Ara h 6 in human breast milk were established. The kinetics of secreted Ara h 2 and Ara h 6 seem to be similar but with a difference in concentration. Follow-up investigations on their tolerogenic or sensitizing properties in breast milk become now accessible., (© 2017 S. Karger AG, Basel.)

Background: In our country, the prevalence and the factors associated to peanut allergy are unknown, a health problem that has been emerging worldwide., Objective: To establish the prevalence and the factors that are associated to peanut allergy amongst school children., Methods: This is a population-based cross-sectional study. We included 756 children aged 6-7 years. The children's parents were questioned about their peanut intake habits. A structured questionnaire was applied, it included questions regarding peanut intake; family and personal history of asthma; rhinitis; and atopic dermatitis. Allergic reactions to peanuts were registered as: probable, convincing and systematic. The statistical analyses included logistical regression models to look for associated factors., Results: Males were 356/756 (47.1%). Peanut allergy prevalence: probable reaction: 14/756 (1.8%), convincing reaction: 8/756 (1.1%) and systemic reaction: 3/756 (0.4%). Through multivariate analysis, the presence of symptoms of allergic rhinitis (OR=4.2 95% CI 1.3-13.2) and atopic dermatitis (OR=5.2; 95% CI 1.4-19.5) during the previous year, showed significant association to probable peanut reaction. The former year, the presence of atopic dermatitis was the only variable that was substantially associated to a convincing reaction (OR=7.5; 95% CI 1.4-38.4) and to a systematic reaction (OR=45.1; 95% CI 4.0-510.0), respectively., Conclusions: The reported prevalence of peanut allergy was consistent with that found in previous studies; symptoms of allergic rhinitis and atopic dermatitis were identified as associated factors to peanut allergy., (Copyright © 2016 SEICAP. Published by Elsevier España, S.L.U. All rights reserved.)

Background: Food allergy is an important public health problem because it affects children and adults, can be severe and even life-threatening, and may be increasing in prevalence. Beginning in 2008, the National Institute of Allergy and Infectious Diseases, working with other organizations and advocacy groups, led the development of the first clinical guidelines for the diagnosis and management of food allergy. A recent landmark clinical trial and other emerging data suggest that peanut allergy can be prevented through introduction of peanut-containing foods beginning in infancy., Objectives: Prompted by these findings, along with 25 professional organizations, federal agencies, and patient advocacy groups, the National Institute of Allergy and Infectious Diseases facilitated development of addendum guidelines to specifically address the prevention of peanut allergy., Results: The addendum provides 3 separate guidelines for infants at various risk levels for the development of peanut allergy and is intended for use by a wide variety of health care providers. Topics addressed include the definition of risk categories, appropriate use of testing (specific IgE measurement, skin prick tests, and oral food challenges), and the timing and approaches for introduction of peanut-containing foods in the health care provider's office or at home. The addendum guidelines provide the background, rationale, and strength of evidence for each recommendation., Conclusions: Guidelines have been developed for early introduction of peanut-containing foods into the diets of infants at various risk levels for peanut allergy., (Published by Elsevier Inc.)

Background: Anaphylaxis is a severe and potentially lethal allergic reaction whose incidence is increasing. Murine models can elucidate the underlying mechanisms and pave the way for appropriate therapeutic options. However, differences in strains and protocols hamper comparisons of data between researchers. We performed a parallel study of clinical and immune responses with 2 strains of mice, BALB/c and C3H/HeOuJ, in an allergen-induced systemic anaphylaxis protocol. Both strains have been widely used in allergy models, although they have not been compared in an intraperitoneal systemic model., Methods: Groups of 5-week-old female BALB/c and C3H/HeOuJ mice were intraperitoneally sensitized with peanut in the presence of adjuvants. Specific immunoglobulin (sIg) G1, sIgG2a, sIgE, total IgE, histamine release, and specific stimulated splenocyte cytokines, interleukin (IL)-4, IL-5, IL-10, IL-12, IL-13, and interferon (IFN)-γ, were assessed. At week 6, mice were intraperitoneally challenged with peanut. Anaphylaxis was evaluated by recognition of clinical symptoms and changes in body temperature., Results: All peanut-sensitized mice induced sIg and developed anaphylactic symptoms upon challenge. Nonetheless, the C3H/HeOuJ strain demonstrated earlier and persistently higher sIgG1 and sIgG2a production, elevated sIgE, and more severe clinical symptoms and histamine release than the BALB/c strain. In contrast, BALB/c exhibited higher release of IL-4, IL-5, IL-10, IL-13, and IFN-γ., Conclusions: Both models are suitable for studying anaphylaxis. Consequently, they could be used in research on the pathogenesis and therapy of anaphylaxis. However, according to the type of study performed, differences in the specific clinical, humoral, and cellular responses to antigens have to be considered., (© 2017 S. Karger AG, Basel.)

Background: Food allergy is an important public health problem because it affects children and adults, can be severe and even life-threatening, and may be increasing in prevalence. Beginning in 2008, the National Institute of Allergy and Infectious Diseases, working with other organizations and advocacy groups, led the development of the first clinical guidelines for the diagnosis and management of food allergy. A recent landmark clinical trial and other emerging data suggest that peanut allergy can be prevented through introduction of peanut-containing foods beginning in infancy., Objectives: Prompted by these findings, along with 25 professional organizations, federal agencies, and patient advocacy groups, the National Institute of Allergy and Infectious Diseases facilitated development of addendum guidelines to specifically address the prevention of peanut allergy., Results: The addendum provides three separate guidelines for infants at various risk levels for the development of peanut allergy and is intended for use by a wide variety of health care providers. Topics addressed include the definition of risk categories, appropriate use of testing (specific IgE measurement, skin prick tests, and oral food challenges), and the timing and approaches for introduction of peanut-containing foods in the health care provider's office or at home. The addendum guidelines provide the background, rationale, and strength of evidence for each recommendation., Conclusions: Guidelines have been developed for early introduction of peanut-containing foods into the diets of infants at various risk levels for peanut allergy., (Published 2017. This article is a U.S. Government work and is in the public domain in the USA.)

Background: Severe anaphylactic symptoms can occur during oral food challenges (OFCs). Thus, high-risk patients (e.g., patients with a history of anaphylaxis or high antigen-specific immunoglobulin E [IgE] levels) must carefully undergo OFCs in hospitals. We attempted to identify the risk factors for severe symptoms during OFC testing among high-risk patients., Methods: We retrospectively evaluated patients' characteristics and severe symptoms that were experienced during a double-blind placebo-controlled food challenge test performed before the patients underwent oral immunotherapy between June 2008 and June 2012. Patients were ≥5 years old and had an anaphylactic history or antigen-specific IgE (>30 kUA/L). Severe symptoms were defined using the grading of the Japanese Anaphylaxis Guidelines, which are modified from the European Academy of Allergology and Clinical Immunology Guidelines., Results: We evaluated 393 cases with positive test results, including 98 cases with severe symptoms. The most frequent severe symptoms were respiratory (77%), gastrointestinal (28%), cardiovascular (27%), and neurological (13%) symptoms. Multivariate analysis revealed that the significant factors for a severe reaction were a history of anaphylaxis to the causative food (adjusted odds ratio [OR]: 2.147, p = 0.003), older age (per 1 year increase, adjusted OR: 1.102, p = 0.044), and an egg OFC (adjusted OR: 0.433, p = 0.003)., Conclusions: The risk factors for a severe reaction to OFCs were a history of an anaphylactic reaction and older age. An egg OFC was associated with low risk of severe symptoms during OFC. Therefore, OFCs for patients with these risk factors should only be performed under specialist supervision with access to rapid treatment and full resuscitation equipment., (© 2017 The Author(s) Published by S. Karger AG, Basel.)