Food Allergic Research Articles

IgE and non-IgE food allergy: A review of immunological mechanisms.

Food allergic (FA) conditions have been classified as immunoglobulin E (IgE) and non-IgE-mediated reactions that affect as many as 8% of young children and 2% of adults in Western countries, and their prevalence seems to be rising. Although the immunologic basis of IgE-mediated FA is well established, the mechanisms that govern non-IgE-mediated FA are not well understood and are marked by a paucity of comprehensive insights. The purpose of the present report is to examine the current classification and epidemiology of non-IgE-mediated FA, the latest immunologic mechanisms that underlie the three most commonly cited non-IgE FA conditions, viz., eosinophilic esophagitis, food protein-induced enterocolitis, and food protein-induced allergic proctocolitis, and explore what allergist/immunologists in practice should be aware of with regard to the condition. An extensive research was conducted in medical literature data bases by applying terms such as FA, non-IgE allergy, tolerance, unresponsiveness, cytokines, CD4+ T helper cell pathways, and key cytokine pathways involved in FA. Current evidence now supports the view that immune dysregulation and cytokine-induced inflammation are the fundamental bases for both IgE- and non-IgE-mediated FA. The existing non-IgE-related FA literature is mostly characterized by a relative dearth of mechanistic information in contrast to IgE-mediated FA, in which the immunologic underpinnings as a T helper type 2 directed entity are well established. Although the need for future methodologic research and adherence to rigorous scientific protocols is essential, it is also necessary to acknowledge past contributions that have given much to our understanding of the condition. In the present report, a novel signature cytokine-based classification of IgE-mediated and non-IgE-mediated allergy is proposed that may offer a novel template for future research in the field of non-IgE-mediated FA. The present report provides an overview of the current classification and frequency of IgE- and non-IgE-mediated FAs, and offers insights and potential solutions to address lingering questions, particularly when concerning the latest immunologic mechanisms that underlie the pathogenesis of non-IgE-mediated FA. Although some progress has been made in recent years toward making diagnostic and treatment options available for these conditions, there still remain many lingering questions and concerns to be addressed, which can be fully understood by future research.

Deserters on the Atopic March: Risk Factors, Immune Profile and Clinical Outcomes of Food Sensitized-Tolerant Infants

To investigate the phenotypic features of infants who demonstrate immunoglobulin E sensitization to foods that they clinically tolerate. Such understanding may help elucidate strategies in the prevention of food allergies.A birth cohort of 1074 from southeastern Australia was composed of subjects <32 weeks’ gestation at time of enrollment and the mother planning to give birth at a local hospital. Participants were characterized as nonsensitized, sensitized-tolerant (ST), or food allergic (FA) on the basis of skin-prick testing and food challenge at 12 month of age.Environmental exposures were recorded throughout the study period of the cohort. Cord blood regulatory T-cell populations were measured at birth. Subsequent childhood allergic disease was assessed by parent report, clinical examination, and repeat skin-prick testing.Covariants were assessed among nonsensitized (n = 698), ST (n = 27), and FA (n = 61) groups and revealed that the ST group was more similar to the nonsensitized group than to the FA group in the following measures: family history of eczema (nonsensitized: 44.6%; ST: 44.6%; FA: 65.6%), pet ownership at 12 months (nonsensitized: 71.5%; ST: 81.5%; FA: 45.8%), eczema during the first 12 months (nonsensitized: 19%; ST: 32%; FA: 64%), and aeroallergen sensitivity at the age of 4 years (nonsensitized: 19.1%; ST 28.6%; FA 44.4%). At birth, a higher proportion of activated regulatory T cells was associated with the ST group.Infants who are sensitized but tolerant have similar pattern of exposures, immunity, and outcomes to nonsensitized infants. An elevated proportion of activated regulatory T cells at birth was specific to the ST infants and may be relevant to the clinical suppression of disease.Genetic and environmental factors are well known to play a role in the development of allergies. With this study, the authors compare prebirth cohorts to determine more specific factors that may put infants at higher risk for developing food allergies. A robust method of skin-prick testing plus an oral food challenge was used to confirm food allergies. The differences in proportion of cord blood naïve versus activated regulatory T cells in cohort groups provides insight into a mechanism for the prevention of food allergies.

Quality of Life in Food Allergic Children and Adolescents at a Community Educational Symposium

The purpose of this study was to determine whether quality of life (QoL) differed between food allergic (FA) adolescents and children who participated in an educational Food Allergy Symposium (FAS) from 2018-2019.

Deserters on the atopic march: Risk factors, immune profile and clinical outcomes of food sensitized-tolerant infants.

A few studies have investigated the antecedents and outcomes of infants who demonstrate IgE sensitization to foods that they clinically tolerate. Improved understanding of this sensitized-tolerant phenotype may inform strategies for the prevention of food allergy. In an Australian birth cohort (n=1074), assembled using an unselected antenatal sampling frame, participants were categorized as nonsensitized (NS), sensitizedtolerant (ST), or food allergic (FA) based on skin prick testing and food challenge at 12months of age. Environmental exposures were recorded throughout. Cord blood regulatory T-cell populations were measured at birth. Subsequent childhood allergic disease was assessed by parent report, clinical examination, and repeat skin prick testing. The covariates of interest varied between NS (n=698), ST (n=27), and FA (n=61) groups as follows, suggesting that across these measures, the ST group was more similar to the NS than the FA group: family history of eczema NS 44.6%, ST. 44.6%, FA 65.6%; pet ownership at 12months: NS 71.5%, ST 81.5%, FA 45.8%; eczema during the first 12months: NS 19%, ST 32%, FA 64%; and aeroallergen sensitization at 4years: NS 19.1%, ST 28.6%, FA 44.4%. At birth, a higher proportion of activated regulatory T cells was associated with ST (OR=2.89, 95% CI 1.03-8.16, P=.045). Food-sensitized-tolerance in infancy appears to be associated with a similar pattern of exposures, immunity, and outcomes to nonsensitized infants. In addition, we found some evidence that an elevated proportion of activated regulatory T cells at birth was specific to the sensitized-tolerant infants, which may be relevant to suppression of clinical disease.

Western blot analysis of sera from dogs with suspected food allergy.

Food allergy is often suspected in dogs with clinical signs of atopic dermatitis. This diagnosis is confirmed with an elimination diet and a subsequent challenge with regular food. Laboratory tests for the diagnosis of food allergy in dogs are unreliable and/or technically difficult. Cyno-DIAL® is a Western blot method that might assist with the selection of an appropriate elimination diet. To evaluate the performance of Cyno-DIAL® for the selection of an elimination diet and diagnosis of food allergy. Thirty eight dogs with atopic dermatitis completed an elimination diet. Combining the results of the diet trials and the challenges, 14 dogs were classified as food allergic (FA), 22 as nonfood-allergic and two as ambiguous cases. Amongst all dogs and amongst dogs with a clinical diagnosis of FA, 3% and 7% (respectively) were positive to Royal Canin Anallergenic® , Vet-Concept Kanguru® or Vet-Concept Dog Sana® ; 8% and 7% to Hill's d/d Duck and Rice® ; 8% and 21% to Hill's z/d Ultra Allergen Free® ; 53% and 64% to Eukanuba Dermatosis FP® ; and 32% and 43% to a home-cooked diet of horse meat, potatoes and zucchini. The specificity and sensitivity of Cyno-DIAL® for diagnosing food allergy were 73% and 71%, respectively. Although Cyno-DIAL® was considered potentially useful for identifying appropriate foods for elimination diet trials, it cannot be recommended for the diagnosis of food allergy. The Cyno-DIAL® test performed better than some previously evaluated ELISA-based tests.

Transforming growth factor beta (TGFβ1) in breast milk and indicators of infant atopy in a birth cohort.

The infant gut's ability to suppress immunologic reactions to food proteins could be influenced by levels of TGFβ in breast milk. We hypothesized that lower levels of TGFβ(1) in the breast milk (BM) of mothers in the WHEALS birth cohort are associated with atopy at infant age 2-3 yrs. We used data collected during infancy in addition to the results of skin prick tests (SPT+) and measures of specific IgE >0.35 IU/ml (spIgE) to milk, egg, and peanut at infant age 2-3 years. Infants were classified as food allergic (FA) based on parental report of infant symptoms/diagnoses and information from clinical assessments. Data for 304 cohort members were analyzed. Among non-black infants, BM-TGFβ(1) was lower for those classified as FA (vs. no FA) and those SPT+ (vs., SPT-), geometric mean = 1100 pg/ml vs. 1417pg/ml, p = 0.081; and 1100 pg/ml vs. 1415pg/ml, p = 0.064, respectively. Among infants of non-atopic mothers, BM-TGFβ(1) was lower for those with elevated (vs. not elevated) sIgE, geometric mean = 1347 pg/ml vs. 1651 pg/ml, p = 0.047. Using logistic regression, adjusted odds ratios describing the association of BM-TGFβ1 to the presence of atopic indicators in the infant were in the hypothesized direction only for non-black infants of non-atopic mothers: aORs for FA, sIgE and SPT+ were 0.08, 0.34, and 0.26 respectively; p = 0.091, 0.13, and 0.23. Immune benefit of BM-TGFβ(1) could inform prevention strategies. Evidence of an association appears greatly influenced by infant race and maternal atopy. More research can determine if these relationships represent a modifiable risk factor for the development of food allergy in certain subgroups.