Oral immunotherapy for food allergy

Allergen-Encapsulating Nanoparticles Reprogram Pathogenic Allergen-Specific Th2 Cells to Suppress Food Allergy

Food allergy is a prevalent, potentially deadly disease caused by inadvertent sensitization to benign food antigens. Pathogenic Th2 cells are a major driver for disease, and allergen-specific immunotherapies (AIT) aim to increase the allergen threshold required to elicit severe allergic symptoms. However, the majority of AIT approaches require lengthy treatments and convey transient disease suppression, likely due to insufficient targeting of pathogenic Th2 responses. Here, the ability of allergen-encapsulating nanoparticles to directly suppress pathogenic Th2 responses and reactivity is investigated in a mouse model of food allergy. NPs associate with pro-tolerogenic antigen presenting cells, provoking accumulation of antigen-specific, functionally suppressive regulatory T cells in the small intestine lamina propria. Two intravenous doses of allergen encapsulated in poly(lactide-co-glycolide) nanoparticles (NPs) significantly reduces oral food challenge (OFC)-induced anaphylaxis. Importantly, NP treatment alters the fates of pathogenic allergen-specific Th2 cells, reprogramming these cells toward CD25+FoxP3+ regulatory and CD73+FR4+ anergic phenotypes. NP-mediated reductions in the frequency of effector cells in the gut and mast cell degranulation following OFC are also demonstrated. These studies reveal mechanisms by which an allergen-encapsulating NP therapy and, more broadly, allergen-specific immunotherapies, can rapidly attenuate allergic responses by targeting pathogenic Th2 cells.

IgE-Mediated food allergy: Current diagnostic modalities and novel biomarkers with robust potential

Food allergy (FA) is a serious public health issue afflicting millions of people globally, with an estimated prevalence ranging from 1-10%. Management of FA is challenging due to overly restrictive diets and the lack of diagnostic approaches with high accuracy and prediction. Although measurement of serum-specific antibodies combined with patient medical history and skin prick test is a useful diagnostic tool, it is still an imprecise predictor of clinical reactivity with a high false-positive rate. The double-blind placebo-controlled food challenge represents the gold standard for FA diagnosis; however, it requires large healthcare and involves the risk of acute onset of allergic reactions. Improvement in our understanding of the molecular mechanism underlying allergic disease pathology, development of omics-based methods, and advances in bioinformatics have boosted the generation of a number of robust diagnostic biomarkers of FA. In this review, we discuss how traditional diagnostic modalities guide appropriate diagnosis and management of FA in clinical practice, as well as uncover the potential of the latest biomarkers for the diagnosis, monitoring, and prediction of FA. We also raise perspectives for precise and targeted medical intervention to fill the gap in the diagnosis of FA.

Oropharyngeal symptoms without systemic reactions as a risk factor for food allergen intolerance: a longitudinal pediatric study

Background

The determinants of tolerance to food allergens are not fully understood. We aimed to elucidate the longitudinal association between oropharyngeal symptoms without systemic reactions (OSw/oS) and tolerance to food allergens.

Methods

We included all patients diagnosed with single food allergy to egg (n = 121), milk (n = 55), and wheat (n = 41) using the oral food challenge test (OFC) from 2014 to 2017. These patients received oral immunotherapy at home and/or in the hospital after diagnosis by OFC. We compared the incidence proportion of tolerance within 2 years by OSw/oS and other variables for 217 patients with food allergy. We defined OSw/oS as isolated symptoms of oropharyngeal discomfort that occurred after ingestion of a safe dose of the allergenic food determined by the OFC in the first 6 months.

Results

Of the 217 patients (median age 37.5 months, male 64.5%), 53 developed OSw/oS (24.4%), and 151 (egg, 85 milk, 36 and wheat, 30) attained tolerance in 2 years. Patients without OSw/oS showed a significantly higher incidence of tolerance than those with the symptoms (crude hazard ratio [HR] 5.62, 95% confidence interval [CI] 3.58–8.82, p < 0.001). The association was consistently significant in the multivariable model (adjusted HR 9.50, 95% CI 5.25–17.20, p < 0.001) independent of other risk factors for intolerance, such as concomitant bronchial asthma (adjusted HR 3.33), history of anaphylaxis (adjusted HR 2.16), milk allergy (adjusted HR 2.02), and allergic symptoms with low dose OFC (adjusted HR 1.52).

Conclusion

Our results suggest that OSw/oS may be a risk factor for intolerance to food allergens. To reveal a high risk of food allergen intolerance may help patients and their families as well as healthcare professionals prepare for the challenge of continuing oral immunotherapy.

Pharmacokinetics and Metabolism Study of Deep-Sea-Derived Butyrolactone I in Rats by UHPLC-MS/MS and UHPLC-Q-TOF-MS

Butyrolactone I (BTL-I) is a butanolide isolated from the deep-sea-derived fungus, Aspergillus sp. It provides a potential new target for the prevention and treatment of food allergies. This study aimed to investigate the metabolic and pharmacokinetic profile of BTL-I in rats. The metabolic profiles were obtained by UHPLC–Q-TOF-MS. As a result, eleven metabolites were structurally identified, and the proposed metabolic pathways of BTL-I were characterized. The main metabolites were the oxidative and glucuronidative metabolites. In addition, a sensitive UHPLC–MS/MS method was established for the quantitation of BTL-I in rat plasma (LOQ = 2 ng/mL). The method was fully validated and successfully applied to the pharmacokinetic study of BTL-I in rats after oral administration or intravenous administration. The oral bioavailability was calculated as 6.29%, and the maximum plasma concentrations were 9.85 ± 1.54 ng/mL and 17.97 ± 1.36 ng/mL for intravenous and intragastric dosing groups, respectively.

Potential Biomarkers, Risk Factors and their Associations with IgE-mediated Food Allergy in Early Life: A Narrative Review

Food allergy affects the quality of life of millions of people worldwide and presents a significant psychological and financial burden for both national and international public health. In the past few decades, the prevalence of allergic disease has been on the rise worldwide. Identified risk factors for food allergy include family history, mode of delivery, variations in infant feeding practices, prior diagnosis of other atopic diseases such as eczema, and social economic status. Identifying reliable biomarkers which predict the risk of developing food allergy in early life would be valuable in both preventing morbidity and mortality and by making current interventions available at the earliest opportunity. There is also the potential to identify new therapeutic targets. This narrative review provides details on the genetic, epigenetic, dietary and microbiome influences upon the development of food allergy and synthesizes the currently available data indicating potential biomarkers. While there is a large body of research evidence available within each field of potential risk factors, there are very limited number of studies which span multiple methodological fields, for example including immunology, microbiome, genetic/epigenetic factors and dietary assessment. We recommend that further collaborative research with detailed cohort phenotyping is required to identify biomarkers, and whether these vary between at-risk populations and the wider population. The low incidence of oral food challenge confirmed food allergy in the general population, and the complexities of designing nutritional intervention studies will provide challenges for researchers to address in generating high quality, reliable and reproducible research findings.

STATEMENT OF SIGNIFICANCE

Food allergy affects the quality of life of millions of people worldwide and presents a significant psychological and financial burden for both national and international public health. Identifying reliable biomarkers which predict the risk of developing food allergy would be valuable in both preventing morbidity and mortality and by making current interventions available at the earliest opportunity. This review provides details on the genetic, epigenetic, dietary and microbiome influences upon the development of food allergy. This helps in identifying reliable biomarkers to predict the risk of developing food allergy, which could be valuable in both preventing morbidity and mortality and by making interventions available at the earliest opportunity.

AIT: New Avenues in Allergen Immunotherapy

During the last decades a substantial increase of allergic diseases has been noticed including allergic asthma and rhinoconjunctivitis as well as food allergies. Since efficient avoidance of airborne - and often hidden - food allergens is not possible, allergen immunotherapy (AIT) is the only causative treatment with the goal of inducing allergen tolerance in affected individuals. Efficacy as well as safety of AIT significantly depends on how the allergen is presented to the immune system, meaning both the route and the form of its application. Here, new ways of allergen administration have lately been explored, some of which are auspicious candidates for successful implementation in the therapeutic management of immediate-type allergies. While the first oral AIT has been approved recently by the FDA for the treatment of peanut allergy, further interesting routes of allergen application include either epicutaneous, intradermal, intranasal, or intralymphatic delivery. Besides, rather the immunologically relevant peptides instead of whole allergen may be administered to develop tolerance. In this chapter, we will describe these new and promising avenues of allergen application in the field of AIT. In addition, we will discuss their potential for future treatment of IgE-mediated allergic diseases enhancing therapeutic efficiency while further minimizing the risks of adverse events.

Biologics in food allergy: up-to-date

Introduction: In recent years, the advent of immunotherapy has remarkably improved the management of IgE-mediated food allergy. However, some barriers still exist. Therefore, the effort of researchers aims to investigate new perspectives in the field of non-allergen specific therapy, also based on the current knowledge of the pathogenesis of this disease.Areas covered: This review aims to focus on the role of biologics as a treatment option in patients with IgE-mediated food allergy. These agents are characterized by their ability to inactivate the Th2 pro-inflammatory pathways. Biologics can be used both alone and in association with immunotherapy. Monoclonal antibodies targeting IgE, the IL-4/IL-13 axis, IL-5, and alarmins have been proposed and investigated for treating food allergy.Expert opinion: The clinical efficacy and safety of biologics have been demonstrated in several preclinical studies and randomized controlled trials. Future studies are still required to address current unmet needs, including the identification of the optimal dose to be used by ensuring the effectiveness of therapy.

Vaccines as therapies for food allergies

Food allergy is a growing public health epidemic with few available treatments beyond allergen avoidance and rescue medications for accidental exposures. A major focus of therapeutic development for food allergies is allergen-specific immunotherapy (AIT) in which patients are exposed to increasing amounts of allergen in controlled dosing to induce desensitization or tolerance. The work of the past few decades has culminated in the recent FDA approval of a peanut product for oral AIT for peanut allergies. Despite these advances, current AIT protocols are cumbersome, take a long time to reach clinical benefit and often have significant side effects. Therefore, there is a great need to develop new therapeutics for food allergy. One area of research aims to improve AIT through the use of adjuvants which are substances traditionally added to vaccines to stimulate or direct a specific immune response. Adjuvants that induce Th1-polarized and regulatory immune responses while suppressing Th2 immunity have shown the most promise in animal models. The addition of adjuvants to AIT may reduce the amount and frequency of allergen required to achieve clinical benefit and may induce more long-lasting immune responses. In this chapter, we highlight examples of adjuvanted AIT and vaccines in development to treat food allergies.

Impact du confinement sur le suivi des immunothérapies orales alimentaires : étude multicentrique dans 3 centres d’Île-de-France

But de l’étude

Plusieurs études ont confirmé l’impact du confinement sur la population, entraînant une rupture de soins, des effets somatiques et psychologiques. Notre étude s’intéresse aux effets indésirables et aux problèmes d’observance au cours d’immunothérapie orale (ITO) alimentaires pendant le confinement.

Patients et méthodes

Au total, 132 patients, majoritairement des enfants (95 %), avec un antécédent atopique (60 %) suivis pour une ITO ont été inclus dans 3 centres d’allergologie en Île-de-France, pendant le confinement lié à la pandémie SARS-Cov-2 du 16/03 au 11/05/20. Les aliments des ITO étaient principalement l’arachide (38 %), le lait de vache (24 %), la noisette (14 %), l’œuf (9 %), la noix de cajou et la pistache (8 %).

Résultats

Des effets indésirables ont été retrouvés chez 13 patients soit 10 % des cas. Ces réactions étaient principalement de grade 1 et 2 selon la classification de Ring et Messmer. Trois patients ont présenté des réactions de grade 3 et six patients ont utilisé l’adrénaline au domicile. L’observance était correcte dans 81 % des cas sans aucun oubli. Trois patients ont augmenté leur dose quotidienne sans avis médical. Nous n’avons pas retrouvé de différence significative dans l’analyse en sous-groupe comparant des enfants appariés en âge suivis en ITO en 2019 et en 2020 sur la même période dans le même hôpital.

Conclusion

Il n’y a pas eu d’augmentation des effets indésirables au cours d’ITO pendant la période du confinement. L’éducation thérapeutique au cours de l’ITO est primordiale et participe à réduire la survenue d’effets indésirables.

IgE in the pathophysiology and therapy of food allergy

Food allergy is becoming a major public health issue, with no regulatory approved therapy to date. Food allergy symptoms range from skin rash and gastrointestinal symptoms to anaphylaxis, a potentially fatal systemic allergic shock reaction. IgE antibodies are thought to contribute importantly to key features of food allergy and anaphylaxis, and measurement of allergen-specific IgE is fundamental in diagnosing food allergy. This review will discuss recent advances in the regulation of IgE production and IgE repertoires in food allergy. We will describe the current understanding of the role of IgE and its high-affinity receptor FcεRI in food allergy and anaphylaxis, by reviewing insights gained from analyses of mouse models. Finally, we will review data derived from clinical studies of the effect of anti-IgE therapeutic monoclonal antibodies (mAbs) in food allergy, and recent insight on the efficiency and mechanisms through which these mAbs block IgE effector functions.

Fecal microbiome and metabolome differ in healthy and food-allergic twins

BACKGROUNDThere has been a striking generational increase in the prevalence of food allergies. We have proposed that this increase can be explained, in part, by alterations in the commensal microbiome.METHODSTo identify bacterial signatures and metabolic pathways that may influence the expression of this disease, we collected fecal samples from a unique, well-controlled cohort of twins concordant or discordant for food allergy. Samples were analyzed by integrating 16S rRNA gene amplicon sequencing and liquid chromatography-tandem mass spectrometry metabolite profiling.RESULTSA bacterial signature of 64 operational taxonomic units (OTUs) distinguished healthy from allergic twins; the OTUs enriched in the healthy twins were largely taxa from the Clostridia class. We detected significant enrichment in distinct metabolite pathways in each group. The enrichment of diacylglycerol in healthy twins is of particular interest for its potential as a readily measurable fecal biomarker of health. In addition, an integrated microbial-metabolomic analysis identified a significant association between healthy twins and Phascolarctobacterium faecium and Ruminococcus bromii, suggesting new possibilities for the development of live microbiome-modulating biotherapeutics.CONCLUSIONTwin pairs exhibited significant differences in their fecal microbiomes and metabolomes through adulthood, suggesting that the gut microbiota may play a protective role in patients with food allergies beyond the infant stage.TRIAL REGISTRATIONParticipants in this study were recruited as part of an observational study (ClinicalTrials.gov NCT01613885) at multiple sites from 2014 to 2018.FUNDINGThis work was supported by the Sunshine Charitable Foundation; the Moss Family Foundation; the National Institute of Allergy and Infectious Diseases (NIAID) (R56AI134923 and R01AI 140134); the Sean N. Parker Center for Allergy and Asthma Research; the National Heart, Lung, and Blood Institute (R01 HL 118612); the Orsak family; the Kepner family; and the Stanford Institute for Immunity, Transplant and Infection.

Quality of life of children aged 8-12 years undergoing food allergy oral immunotherapy: Child and parent perspective

BACKGROUND

Oral immunotherapy (OIT) for food allergy improves the quality of life (QOL) of children from parental perspective but little is known about the child perception.

METHODS

The Food Allergy Quality of Life Questionnaire-Child Form (FAQLQ-CF) was administered to children aged 8-12 years, and the FAQLQ-Parent Form (FAQLQ-PF) was administered to their parents at the start of OIT for milk, egg, peanut, sesame, or tree nuts, at the end of up-dosing, and after 6 months of follow-up. Food-allergic children not undergoing OIT served as controls. Children QOL scores were compared to their parents.

RESULTS

The total FAQLQ-CF score of 103 children undergoing OIT improved significantly from start of OIT (median (IQR); 4.8, 3.8-5.7) to end of up-dosing (3.9, 3-5.2) (P < .001). A greater improvement was noted in the 56 children who reached a follow-up visit, from 5.0 (3.7-5.8) at OIT start to 3.1 (1.8-5.0) on follow-up, (P < .001). In contrast, FAQLQ-CF scores of control patients improved mildly and nonsignificantly between the two time points from 5.3 (4.3-5.7) to 4.8 (3.6-6.0), (P = .13). The improvement in the total FAQLQ-CF scores from OIT start to follow-up was significantly greater compared to the change in control patients during observation (P = .015). Parents reported better QOL scores compared to their children at all stages of OIT (start 4.0, 3.2-5, P = .004; end of up-dosing 2.9, 1.9-4.7, P = .04; follow-up 2.2, 1.6-3.6, P = .003).

CONCLUSIONS

QOL of food-allergic children undergoing OIT improves significantly compared to controls. Parents perceive QOL to be better than the perception of the children.

Slow low-dose oral immunotherapy: Threshold and immunological change

BACKGROUND

We examined the feasibility, efficacy and safety of slow low-dose oral immunotherapy (SLOIT) for egg, milk, wheat allergies, with accepted severity-stratified initial and maintenance doses.

METHODS

Children with food allergies defined by low-dose oral food challenges (LD-OFCs) to hen's egg (cumulative protein dose up to 983 mg, n = 133), cow's milk (287 mg, n = 50), and wheat (226 mg, n = 45) were recruited. Participants were divided into two groups [SLOIT and control (complete avoidance]) based on their preferences. Participants who selected SLOIT were instructed to take the safe dose daily, with monthly increases, aiming to increase the dose by 10 times in one year. The primary outcome was the proportion of participants who passed the LD-OFCs following 1 year of therapy.

RESULTS

The participants in SLOIT group ingested their antigen 92.9% of the therapy's day on average. The proportion of participants who passed LD-OFCs was 35.9% (61/170) in the SLOIT group and 8.7% (4/46) in the control group (P < .001); no large differences were observed among allergens. Among the subjects who failed LD-OFCs, the median change in the total dose in the LD-OFC was 235% (interquartile range: 100%-512%) in the SLOIT group and 100% (42%-235%) in the control group (P < .001). Provoked allergic symptoms were observed in only 0.58% (280/48,486) per programmed intake and approximately 50% of the SLOIT group did not experience any obvious allergic symptoms throughout therapy.

CONCLUSIONS

SLOIT showed significant feasibility, efficacy and safety, providing a promising option to manage patients with severe food allergies.

Can food allergy be cured? What are the future prospects?

Food allergies have become a significant heath burden as prevalence continues to rise, affecting 6%-13% of the global population. In the absence of drugs approved by regulatory agencies, the current standard of care remains avoidance of allergenic foods and management of acute allergic reactions with antihistamines and epinephrine autoinjectors. Allergen immunotherapy has been shown to increase the threshold of reactivity in the majority of food-allergic individuals. However, challenges include long treatment periods, high rates of adverse reactions, and lack of permanence of desensitization and established protocols. To address these limitations, adjunctive allergen-specific immunotherapy, vaccines, and non-allergen-specific therapies (eg, monoclonal antibodies) are being explored. The future of food allergy treatment is promising with a number of clinical trials in progress. Currently, although desensitization can be achieved for the majority of individuals with food allergy through immunotherapy, continued ingestion of allergen is needed for most individuals to maintain desensitization. Further understanding of the mechanisms of food allergy and identification of biomarkers to distinguish between temporary and permanent resolution of allergies is needed before a cure, where reactivity to the allergen is permanently lost enabling the individual to consume the allergen in any amount at any time, can be envisioned.

Coumarin alleviates ovalbumin-induced food anaphylaxis in a mouse model by affecting mast cell function

Coumarin is an important organic heterocyclic compound with a wide range of sources in nature. It plays an important role in the drug discovery process due to its existence in diverse biologically active compounds and its broad bioactivity. In this study, the anti-allergic activity of coumarin was evaluated using an ovalbumin (OVA)-induced mouse food allergy model and an immunoglobulin (Ig)E mediated mouse bone marrow-derived mast cell (BMMC) model. Coumarin could alleviate the OVA-induced allergic symptoms, decrease the diarrhea rates, and promote the rectal temperature rise in allergic mice. Moreover, coumarin had the ability to reduce the levels of histamine and mouse mast cell proteinases, inhibit OVA-specific IgE, and significantly decrease the population of mast cells in the spleen and mesenteric lymph nodes. Coumarin could also significantly suppress mast cell-dependent passive cutaneous anaphylaxis. Additionally, the number of mature BMMCs was decreased as coumarin caused the suppression of c-KIT receptors. Furthermore, coumarin up-regulated the apoptosis of OVA-activated BMMCs in a concentration-dependent manner. In conclusion, coumarin displayed effective anti-food allergy activity via the regulation of mast cell function and numbers. Coumarin and its derivatives provide a new direction for the development of anti-food allergic drug components.

Resistance of parvalbumin to gastrointestinal digestion is required for profound and long-lasting prophylactic oral tolerance

Background

Early introduction of food allergens into children's diet is considered as a strategy for the prevention of food allergy. The major fish allergen parvalbumin exhibits high stability against gastrointestinal digestion. We investigated whether resistance of carp parvalbumin to digestion affects oral tolerance induction.

Methods

Natural Cyp c 1, nCyp c 1, and a gastrointestinal digestion‐sensitive recombinant Cyp c 1 mutant, mCyp c 1, were analyzed for their ability to induce oral tolerance in a murine model. Both antigens were compared by gel filtration, circular dichroism measurement, in vitro digestion, and splenocyte proliferation assays using synthetic Cyp c 1‐derived peptides. BALB/c mice were fed once with high doses of nCyp c 1 or mCyp c 1, before sensitization to nCyp c 1. Immunological tolerance was studied by measuring Cyp c 1‐specific antibodies and cellular responses by ELISA, basophil activation, splenocyte proliferations, and intragastric allergen challenge.

Results

Wild‐type and mCyp c 1 showed the same physicochemical properties and shared the same major T‐cell epitope. However, mCyp c 1 was more sensitive to enzymatic digestion in vitro than nCyp c 1. A single high‐dose oral administration of nCyp c 1 but not of mCyp c 1 induced long‐term oral tolerance, characterized by lack of parvalbumin‐specific antibody and cellular responses. Moreover, mCyp c 1‐fed mice, but not nCyp c 1‐fed mice developed allergic symptoms upon challenge with nCyp c 1.

Conclusion

Sensitivity to digestion in the gastrointestinal tract influences the capacity of an allergen to induce prophylactic oral tolerance.

New Developments in Non-allergen-specific Therapy for the Treatment of Food Allergy

PURPOSE OF REVIEW

The prevalence of food allergy is increasing. At the current time, there are no approved treatments for food allergy. Major limitations of immunotherapy are long treatment periods (months or years), frequent clinic visits, high costs, increased risk of adverse events during treatment, and lack of durability of desensitization. Additionally, it is allergen-specific, and in those allergic to multiple allergens, the length and cost of treatment are further increased. In this review, we summarize recent developments in novel non-allergen-specific treatments for food allergy.

RECENT FINDINGS

A number of monoclonal antibodies that block IgE or specific pro-allergenic cytokines or their receptors have shown promise in clinical trials for food allergy. The insight we have gained through the use of one drug for the treatment of an atopic disease is quickly being translated to other atopic diseases, including food allergy. The future for food allergy treatment with biologics looks bright.

The clinical and immune outcomes after food allergen immunotherapy emphasizing the development of tolerance

PURPOSE OF REVIEW

The present review serves to outline the direction of food allergy immunotherapy research with an emphasis on clinical and immunologic outcomes. It helps to delineate sustained unresponsiveness achieved from food immunotherapy as the clinical outcome most similar to immune tolerance.

RECENT FINDINGS

We will discuss the difference between immune tolerance, desensitization, and sustained unresponsiveness in relation to food immunotherapy by discussing the clinical and immunologic changes which have been recently discovered.

SUMMARY

Research has recently shown that oral immunotherapy is most efficacious clinically at achieving desensitization to a food and sustained unresponsiveness.

Molecular Approaches for Diagnosis, Therapy and Prevention of Cow´s Milk Allergy

Cow´s milk is one of the most important and basic nutrients introduced early in life in our diet but can induce IgE-associated allergy. IgE-associated allergy to cow´s milk can cause severe allergic manifestations in the gut, skin and even in the respiratory tract and may lead to life-threatening anaphylactic shock due to the stability of certain cow´s milk allergens. Here, we provide an overview about the allergen molecules in cow´s milk and the advantages of the molecular diagnosis of IgE sensitization to cow´s milk by serology. In addition, we review current strategies for prevention and treatment of cow´s milk allergy and discuss how they could be improved in the future by innovative molecular approaches that are based on defined recombinant allergens, recombinant hypoallergenic allergen derivatives and synthetic peptides.

Food allergies are associated with increased disease activity in multiple sclerosis

OBJECTIVE

The association between allergy and multiple sclerosis (MS) is still unclear. In our study, we assessed the association between a self-reported history of allergic conditions with MS clinical and MRI disease activity.

METHODS

A subset of 1349 patients enrolled in the Comprehensive Longitudinal Investigation of Multiple Sclerosis at the Brigham and Women's Hospital (CLIMB) study completed a self-administered questionnaire on environmental, food and drug allergies. Patients were distributed among four allergy groups: (1) environmental, (2) food, (3) drug, (4) no known allergies (NKA). Clinical (number of attacks, expanded disability status scale (EDSS), MS severity score (MSSS)) and radiological variables (presence of gadolinium-enhancing lesions and lesion count), and their associations with the different allergy groups or those with NKA, were assessed.

RESULTS

The food allergy group had a 1.38 times higher rate for cumulative number of attacks compared with the NKA group (P=0.0062); this difference remained significant in the adjusted analysis (relapse rate ratio 1.27, P=0.0305). The food allergy group showed more than twice the likelihood (OR 2.53, P=0.0096) of having gadolinium-enhancing lesions on MRI. The environmental and drug allergy groups did not show significant differences when compared with the NKA group. The EDSS and MSSS were not affected by any type of allergy.

CONCLUSIONS

MS patients with food allergy had more relapses and a higher likelihood of gadolinium-enhancing lesions compared with patients with no known allergy. Future prospective studies are needed to confirm our findings and investigate underlying biological mechanisms, which may unveil new therapeutic and preventative strategies for MS.

Butyrate Enhances Desensitization Induced by Oral Immunotherapy in Cow's Milk Allergic Mice

Background

In previous studies, we showed that a fructo-oligosaccharide- (FOS-) supplemented diet enhanced oral immunotherapy (OIT) efficacy in a mouse model for cow's milk allergy. Fermentation of FOS by intestinal bacteria leads to production of short-chain fatty acids (SCFA) including butyrate.

Aim

To investigate the contribution of butyrate in the enhanced efficacy of OIT + FOS.

Methods

C3H/HeOuJ mice were sensitized and received OIT with or without FOS or butyrate supplementation. After treatment, whole blood was collected to conduct a basophil activation test (BAT) and allergen challenges were performed to measure acute allergic symptoms. CD4 + CD25 + regulatory T cells (Tregs) were isolated from treated mice or differentiated in vitro and used in a bone marrow-derived mast cell (BMMC) suppression assay. Cecum content was collected to analyze SCFA concentrations.

Results

Allergen-induced basophil activation was reduced in OIT + butyrate samples compared to OIT. Accordingly, the acute allergic skin response and mast cell degranulation upon challenge were reduced in OIT + butyrate and OIT + FOS mice compared to sensitized controls. Butyrate was increased in the cecum content of OIT + FOS mice compared to OIT mice and sensitized controls. Treg-mediated BMMC suppression was enhanced after in vivo butyrate and FOS exposure in combination with OIT but with a more pronounced effect for butyrate.

Conclusion

Butyrate supplementation enhanced OIT-induced desensitization of basophils and mast cells and Treg functionality. Only OIT + FOS treatment induced potential microbial alterations, shown by increased butyrate levels in cecum content. Both butyrate and FOS are promising candidates to improve OIT efficacy in human studies to treat food allergies.

Biomarkers in Food Allergy

PURPOSE OF REVIEW

To familiarize the reader with the concept of precision medicine in food allergy by dealing with the current biomarkers for the diagnosis, prognosis, and management of the disease.

RECENT FINDINGS

Many efforts have been devoted in order to characterize reliable biomarkers able to identify specific phenotypes and endotypes in food allergy. Specific IgE (sIgE), sIgE/total IgE ratios, and T cell assays are just a few candidates that have been investigated over time. With the advent of omics sciences, a new era is commencing. A better understanding of pathogenesis of food allergy and mechanisms of action of the different therapeutic options will allow the accurate selection of the appropriate patient. In the near future, advances in technologies and data interpretation will allow a better understanding of the pathogenesis of food allergy and the identification of proper biomarkers for a personalized treatment tailored on the specific patient's profile.

Deep-Sea-Derived Butyrolactone I Suppresses Ovalbumin-Induced Anaphylaxis by Regulating Mast Cell Function in a Murine Model

Deep-sea-derived butyrolactone I (BTL-I), which was identified as a type of butanolide, was isolated from Aspergillus sp. Ovalbumin (OVA)-induced BALB/c anaphylaxis was established to explore the antifood allergic activity of BTL-I. As a result, BTL-I was able to alleviate OVA-induced allergy symptoms, reduce the levels of histamine and mouse mast cell proteinases, inhibit OVA-specific IgE, and decrease the population of mast cells in the spleen and mesenteric lymph nodes. BTL-I also significantly suppressed mast-dependent passive cutaneous anaphylaxis. Additionally, the maturation of bone marrow-derived mast cells (BMMCs) declined as BTL-I caused down-regulation of c-KIT receptors. Furthermore, molecular docking analyses revealed that BTL-I interacted with the inhibitory receptor, FcγRIIB. In conclusion, the reduction of mast cell function by deep-sea-derived BTL-I as well as its interactions with the inhibitory receptor, FcγRIIB, may contribute to BTL-I-related protection against food anaphylaxis.