Comparison of immune responses and intestinal flora in epicutaneously sensitized BALB/c or C57BL/6 mouse models of food allergy

Cutaneous exposure to food allergens through a disrupted skin barrier is recognized as an important cause of food allergy,and the cutaneous sensitized mouse model has been established to investigate relevant allergic disorders.However,the role of different genetic backgrounds of mice on immune responses to food allergens upon epicutaneous sensitization is largely unknown.In this study,two strains of mice,i.e.,the BALB/c and C57BL/6 mice,were epicutaneously sensitized with ovalbumin on atopic dermatitis(AD)-like skin lesions,followed by intragastric challenge to induce IgE-mediated food allergy.Allergic outcomes were measured as clinical signs,specific antibodies and cytokines,and immune cell subpopulations,as well as changes in intestinal barrier function and gut microbiota.Results showed that both strains of mice exhibited typical food-allergic symptoms with a Th2-skewed response.The C57BL/6 mice,rather than the BALB/c mice,were fitter for establishing an epicutaneously sensitized model of food allergy since a stronger Th2-biased response and severer disruptions in the intestinal barrier and gut homeostasis were observed.This study provides knowledge for selecting an appropriate mouse model to study food-allergic responses associated with AD-like skin lesions and highlights the role of genetic variations in the immune mechanism underlying pathogenesis of food allergy.

Preventive effects of Bifidobacterium lactis Probio-M8 on ovalbumin-induced food allergy in mice

Food allergy is a significant public health concern globally.Certain probiotics have been found to enhance food allergy by regulating immune-microbe interactions in animal models and patients.However,the effects of Bifidobacterium lactis Probio-M8 on food allergy have not been thoroughly investigated.The present study examined the anti-allergic properties of Probio-M8,particularly in relation to immune response and gut microbiota composition.Results demonstrate that oral administration of Probio-M8 effectively mitigated the allergy symptoms triggered by ovalbumin(OVA)by ameliorating the morphological damage in the jejunum,reducing OVA-specific IgE and histamine levels in the serum,and suppressing Th2 cytokines(interleukin(IL)4 and IL-13)while increasing Th1 cytokines(interferon(IFN)γ)and regulatory T(Treg)cytokines(IL-10 and transforming growth factor(TGF)β1)in the culture supernatants of splenic cells.Furthermore,Probio-M8 effectively altered the diversity and composition of gut microbiota,particularly the relative abundances of Akkermansia_muciniphila in OVA-induced mice.Compared to the OVA group,the Probio-M8 group showed a decrease in the relative abundance of Akkermansia_muciniphila.In conclusion,Probio-M8 demonstrates the potential to alleviate food allergy by regulating the Th1/Th2 response and modulating gut microbiota,thereby offering a novel therapeutic strategy for patients with food allergy.

Olive oil ameliorate allergic response in ovalbumin-induced food allergy mouse by promoting intestinal mucosal immunity

The numerous health benefits of olive oil are widely known,however,it also provides anti-allergic properties that have not yet been fully defined.In this study,the anti-allergic activity of olive oil was evaluated by analyzing the clinical symptoms and immune-related factors in BALB/c mice that had ingested600 mg/(kg·day)olive oil for two weeks prior to the evaluation.An allergy model was subsequently constructed for analysis,the results of which showed that the olive oil reduced the scores of allergic symptoms in the mice,and up-regulated the hypothermia and the decline in the immune organ index.Moreover,fewer allergy-related cytokines and reduced intestinal inflammation was discovered in the olive oil-treated group.In addition,analysis of intestinal mucosal immune-related factors revealed that the olive oil promoted the expression of intestinal tight junction proteins(Claudin-1,Occludin,and ZO-1)and IL-22,and helped maintain the integrity of the intestinal epithelial physical barrier.Increased levels of mucin 2 andβ-defensin were also found in the intestinal mucus of the olive oil-treated mice.These findings suggest that the oral administration of olive oil effectively attenuated the ovalbumin-induced allergic immune response in the mice,and had a positive effect on intestinal epithelial mucosal immunity.

The role of gut microbiota and its metabolites short-chain fatty acids in food allergy

Emerging evidence indicated that the increase in food allergy(FA)over the past few decades was associated with the abnormal compositional and metabolic changes of gut microbiota.Gut microbiota played a vital role in maintaining the homeostasis of the immune system and the dysbiosis of gut microbiota promoted the occurrence of FA.Recent research suggested that short-chain fatty acids(SCFAs),the main metabolites derived from gut microbiota,contributed to FA protection.Herein,we provided a comprehensive review on the relationship between gut microbiota and FA.The multifaceted mechanisms underlymg beneficial effects of gut microbiota composition/metabolites on the regulation of diverse cellular pathways in intestinal epithelial cells,dendritic cells,innate lymphoid cells,T cells,B cells and mast cells in the immune system were discussed systematically.These findings emphasized the positive function of gut microbiota in FA and provided novel ideas for the treatment or prevention of FA in the future.

The role of probiotics in prevention and treatment of food allergy

With the prevalence of food allergy increasing every year,food allergy has become a common public health problem.More and more studies have shown that probiotics can intervene in food allergy based on the intestinal mucosal immune system.Probiotics and their metabolites can interact with immune cells and gut microbiota to alleviate food allergy.This review outlines the relationship between the intestinal mucosal immune system and food allergy.This review also presents the clinical application and potential immunomodulation mechanisms of probiotics on food allergy.We aim at providing a reference for further studies to explore the key active substances and immunomodulation mechanisms of anti-allergic probiotics.

Application of in vitro and in vivo models in the study of food allergy

Food allergy is one of the most important food safety problems that has attracted increasing attention.The food allergy experimental models provide not only the accurate allergen detection and evaluation methods but also the powerful approaches for mechanism investigations.In this paper,we reviewed the common food allergy cell models including mast cell,basophil granulocyte and basophil,as well as the animal models of BALB/c mouse,C3H/HeJ mouse,and BN rat.We also introduced zebrafish,a promising model organism for investigating immunity though lacking direct applications in food allergy to date,and focused on traumatic inflammation,bacterial infection and viral infection models.In addition,we also summarized the clinical diagnostic research methods for food allergy.The elucidation of these topics will help researchers to understand the characteristics and mechanisms of various models and thus select the proper models for particular study,so as to support further investigations of food allergy.

Effect of Buzhong Yiqi Decoction (补中益气汤) on Murine Liver Damage Induced by Food Allergy

Objective: To investigate the effect of Buzhong Yiqi decoction (补中益气汤, BZYQD) on liver damage induced by food allergy in mice. Methods: Nc/Jic strain mice with high levels of serum IgE were sensitized by ovalbumin (OVA), and then divided into two groups and respectively treated with BZYQD (treated group) or normal saline (model group). Samples of serum, liver tissues and small intestine were collected two weeks later, and another group of non-sensitized mice was set as the normal group. The levels of serum alanine aminotransferase (ALT) were measured with spectrophotometry. The liver tissue and small intestine were stained with hematoxylin and eosin (HE) for pathologic analysis. The liver samples were also subjected to analysis of CD4-T helper cell and cytokine (interleukin-4, IL-4, interleukin-6, IL-6) expression with immunohistochemical (avidin-biotin complex, ABC) method. Results: Serum ALT levels decreased and obvious pathologic improvements were seen in the mice treated with BZYQD. And compared with the model mice, the number of positive cells of IL-4, IL-6 and CD4 cell decreased significantly in those treated with BZYQD. Conclusion: BZYQD can effectively decrease the production of cytokines associated with allergic reaction in the liver of mice thus effective in treating liver damage caused by food allergy.

Pathophysiological Justification for Allergen Immunotherapy in Food Allergy

Apart from avoiding exposure, allergen immunotherapy (AI) is the only causal method of treating allergic diseases. The results of numerous studies have been published concerning the safety and effectiveness of the AI in treating allergic rhinitis, asthma or allergy to the venom of Hymenoptera insects. It has also been proven that administration of increasing preparation doses of allergen extractions alleviates the symptoms in patients after the exposure to some sensitizing allergens. The effect of the AI remains visible many years after completion of the therapy. Studies have been done in an attempt to employ specific immunotherapy in patients with food allergy symptoms. They have been mostly concerned with populations of patients suffering from allergy to the protein found in cow’s milk and hen eggs. It appears that a need arises to create a new therapeutic method for successful treatment of food allergies and specific allergen immunotherapy seems to be a promising step. Although still in its experimental phase, in many well documented cases the method allows for building patient’s tolerance towards small doses of sensitizing allergen and seems conducive to protecting the patient from anaphylactic reactions after incidental allergen consumption.

Potential risk factors of food allergy in children: EuroPrevall project results in Vilnius, Lithuania

Objectives: In recent decades, the prevalence of allergic diseases, including food allergy, has been increasing. This is becoming an important health problem. Many risk factors of food allergy were identified recently, and many of them still are controversial. The aim of this study was to evaluate the potential risk factors of food allergy in child population following the methodology of the EuroPrevall project. Methods: Vilnius University was a partner in the EuroPrevall integrated project “The prevalence cost and basis of food allergy in Europe”, which is an EU-funded multi-disciplinary research study. A case-control study design was used to address the study question. All subjects were assessed by means of questionnaire and blood sample test for specific immunoglobulin E. Possible risk factors like mother’s addictions (smoking, alcohol drinking during pregnancy), infant low birth weight and nursing duration, gender, treatment with antibiotics during first two years of life were analysed. Multiple logistic regression was used for risk factor analysis. Results: No statistically significant associations were found between risk factors and food allergy. Only gender (male) (ORa = 3.36, 95% CI 1.17-9.63) and mother’s food allergy (ORa = 5.44, 95% CI 1.19-24.97) were directly associated with child’s food allergy. Because of the presence of those both two factors (gender (male) + mother’s allergy), the risk for food allergy increased particularly—OR was 18.31 (95% CI 2.01-166.07). Conclusion: Gender (male) and mother’s food allergy are the most important risk factors directly associated with children’s food allergy.

Data-driven analysis of chemicals,proteins and pathways associated with peanut allergy:from molecular networking to biological interpretation

Peanut allergy is majorly related to severe food induced allergic reactions.Several food including cow's milk,hen's eggs,soy,wheat,peanuts,tree nuts(walnuts,hazelnuts,almonds,cashews,pecans and pistachios),fish and shellfish are responsible for more than 90%of food allergies.Here,we provide promising insights using a large-scale data-driven analysis,comparing the mechanistic feature and biological relevance of different ingredients presents in peanuts,tree nuts(walnuts,almonds,cashews,pecans and pistachios)and soybean.Additionally,we have analysed the chemical compositions of peanuts in different processed form raw,boiled and dry-roasted.Using the data-driven approach we are able to generate new hypotheses to explain why nuclear receptors like the peroxisome proliferator-activated receptors(PPARs)and its isoform and their interaction with dietary lipids may have significant effect on allergic response.The results obtained from this study will direct future experimeantal and clinical studies to understand the role of dietary lipids and PPARisoforms to exert pro-inflammatory or anti-inflammatory functions on cells of the innate immunity and influence antigen presentation to the cells of the adaptive immunity.

Food allergy and related risk factors in 2540 preschool children: an epidemiological survey in Guangdong Province, southern China

Background:Although the number of studies on allergic diseases in the general population of southern China is increasing,only a few have addressed food allergy(FA)in children in this region.The present study aimed to investigate the prevalence,clinical manifestations,spectrum of allergens,and related risk factors of FA in preschool children in Guangdong Province,southern China.Methods:A random cluster-sampling method was used to select 24 kindergartens from 12 cities in Guangdong Province.The parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree relatives.Thereafter,the Chi-square test,multivariate regression analysis,and Spearman's rank-order correlation coefficient analysis were performed to identify statistically significant differences.Results:Analysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%.Adverse food reactions were due to the consumption of shrimp(4.4%),crab(3.2%),mango(2.3%),cow's milk and dairy products(1.9%),and eggs(1.4%).Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in children.Conclusions:The incidence of FA in children in Guangdong Province is higher than that commonly believed.An individual's genetic background is an important risk factor for FA.Hence,mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.

Oral administration of Lactiplantibacillus plantarum 22A-3 exerts anti-allergic activity against intestinal food allergy mouse models sensitized and challenged with ovalbumin

In recent years,researches on food components with anti-allergic effects have been gathering attention,because of the expectation for the establishment of a safe and effective treatment for food allergy.Previous studies have reported that Lactiplantibacillus plantarum 22A-3 (LP22A3) inhibited degranulation of mast cells and reduced IgE production.We have developed a gastrointestinal allergy system in which mice are sensitized by intraperitoneal and oral administration of OVA and then challenged by oral administration of high doses of OVA.As a result,an increase in the amount of IgE in the blood and a decrease in the temperature of the colon were confirmed,and it was clarified that food allergy was induced by oral administration of high dose of OVA as the challenge.Oral administration of LP22A3 ameliorated allergic responses significantly by reducing the amount of IgE in the blood and to recovered the decrease of rectal temperature.However,LP22A3 did not affect the intestinal barrier function.Administered LP22A3 significantly suppressed mRNA expression of OX40L and IL-4.These results suggested that LP22A3 suppressed Th2 differentiation and IL-4 production via downregulation of OX40L,and consequently suppressed IgE production.LP22A3 might provide a safe and effective treatment for allergic diseases due to ability modulating intestinal immune system.

Dupilumab for Treatment of Food-Dependent, Exercise-Induced Anaphylaxis: Report of One Case

Food-dependent,exercise-induced anaphylaxis(FDEIA)is a potentially life-threatening disorder that often occurs with exercise,and patients typically have eaten a specific food within hours before disease onset.This disease is exceedingly rare,with a prevalence of 0.02%.No well-recognized prevention or treatment strategy has been available for FDEIA except avoiding triggers strictly.Here we report an 11-year-old boy with a history of recurrent anaphylaxis of unknown etiology more than 10 times within two years.As the anaphylactic symptoms had not been controlled after traditional treatments,the patient was given subcutaneous injection of dupilumab seven times within 33 weeks.During dupilumab treatments,the patient was exposed to culprit mushrooms plus exercises at least twice a month but without notable anaphylaxis.Thus,dupilumab may improve the allergic reactions in FDEIA patients.

Major allergens in 8 types of allergenic foods and allergen detection techniques

In recent years,the prevalence of allergens in food warning notices,both domestically and internationally,has become the second leading concern after microbial contamination.Among the various factors that threaten human health reported by the World Health Organization,food allergy ranks fourth,and food allergy has become a global security problem.As of now,no definitive treatment for food allergies exists,making the avoidance of allergen-containing foods the most effective prevention method.Consequently,labeling foods with allergen information serves as a crucial warning for allergic populations.Moreover,to enhance comprehension of food allergies,this article provides a brief overview of their definition and sensitization mechanisms.The main focus lies in highlighting the structure of primary allergens found in eight commonly allergenic foods and the resulting clinical symptoms they cause.Additionally,a summary of commonly employed allergen detection techniques is presented,with an analysis of their principles,advantages,and limitations.Looking ahead,the integration of diverse technological approaches to establish an efficient,accurate,and affordable allergen detection method remains a significant trend.This article has certain reference value for understanding the direction of food allergies.

Immunological disturbance effect of exogenous histamine towards key immune cells

Histamine in food has attracted widespread attention due to the potential toxicity and associated health risk.However,its influences on immunological components,especially the function of key immune cells,are still poorly known.In this work,we explored the effects of exogenous histamine on the function of key immune cells such as intestinal epithelial cells,dendritic cells,and T cells.The results showed that histamine could affect the expression of allergy-related genes in CMT93 cells at a high dose of histamine.Moreover,it’s found that histamine could cause an imbalance in the levels of relevant immune factors secreted by dendritic cells and T cells,especially those related to allergy.At the same time,the proportion of MHC class IIpositive dendritic cells and the proportion of T helper 2(Th2)cells in CD4^(+)T cells increased after histamine stimulation.We concluded that the presence of a certain level of histamine in food may affect the expression of allergy-related cytokines,disrupt the balance of the immune homeostasis,and potentially lead to adverse immune reactions.This work demonstrated the importance of including the estimation of histamine’s immune safety in aquatic products rather than merely considering the potential risk of food poisoning.

Oral administration of Bacillus coagulans TQ-35 alleviates allergic responses in OVA-sensitive BALB/c mice

Bacillus coagulans has been extensively studied so far,but there has been a lack of research on its usage in allergy.In this study,we designed to assess the effect of different concentrations of B.coagulans on food allergy in a BALB/c mouse model of ovalbumin(OVA)-induced food allergy and its effect on gut microbes.The assessment of symptoms,specific immunoglobulin E(IgE),T-cell differentiation,and related gene expression levels in sensitized mice by assay indicated that high doses of oral B.coagulans could alleviate allergic symptoms.Treatment with B.coagulans,in the high-dose group,significantly reduced IgE and IgG1 levels and modulated the balance of T helper type 1 cell(Th1)and Th2 and the expression of relevant genes in the spleen.16S rRNA analysis showed that probiotics improved the structure of the microbiota,in particular by boosting the percentage of Clostridia,Bacteroides vulgatus and Enterococcus faecium,and by increasing the abundance of microbial species,thereby modulating the immune system.Therefore,this study can provide insights into the practical application of B.coagulans doses to alleviate OVA allergy.

Evolving strategies: Enhancements in managing eosinophilic esophagitis in pediatric patients

Eosinophilic esophagitis is a newly recognized disease first described about 50 years ago.The definition,diagnosis,and management have evolved with new published consensus guidelines and newly approved treatment available to pediatricians,enabling a better understanding of this disease and more targeted treatment for patients.We describe the definition,presentation,and diagnosis of eosinophilic esophagitis including management,challenges,and future directions in children.The definition,diagnosis,and management of eosinophilic esophagitis have evolved over the last 50 years.Consensus guidelines and newly approved biologic treatment have enabled pediatricians to better understand this disease and allow for more targeted treatment for patients.We describe the definition,presentation,diagnosis,management,and treatment in addition to the challenges and future directions of eosinophilic esophagitis management in children.

Association between Helicobacter pylori infection and food-specific immunoglobulin G in Southwest China

BACKGROUND Helicobacter pylori(H.pylori)has been found to be associated with extragastrointestinal diseases,possibly including adverse food reactions(such as food allergy or intolerance).However,there are few studies on H.pylori and food allergy or intolerance,and the results are inconsistent.Food-specific immunoglobulin(Ig)G has been revealed to be associated with food allergy or intolerance and can be used as a marker to explore the correlation between H.pylori infection and food allergy or intolerance.AIM To explore the relationship between H.pylori infection and food-specific IgG METHODS We retrospectively analyzed the physical examination data of 21822 subjects from February 2014 to December 2018 in this study.H.pylori infection was detected using the 13C urea breath test.Food-specific IgG of eggs,milk and wheat in serum was assessed.Subjects were grouped according to H.pylori positivity,and the positive rates of three kinds of food-specific IgG were compared between the two groups.Multivariable logistic regression analysis was performed to elucidate the association between H.pylori infection and food-specific IgG.RESULTS The total infection rate of H.pylori was 39.3%,and the total food-specific IgGpositive rates of eggs,milk and wheat were 25.2%,9.0%and 4.9%,respectively.The infection rate of H.pylori was higher in males than in females,while the positive rates of food-specific IgG were lower in males than in females.The positive rates of food-specific IgG decreased with age in both males and females.In the H.pylori-positive groups,the positive rates of food-specific IgG of eggs,milk and wheat were all lower than those in the H.pylori-negative groups.Multivariate logistic regression analysis revealed that H.pylori infection was negatively correlated with the food-specific IgG-positive rates of eggs,milk and wheat(odds ratio value of eggs 0.844-0.873,milk 0.741-0.751 and wheat 0.755-0.788,in different models).CONCLUSION H.pylori infection was found to be negatively associated with the food-specific IgG of eggs,milk and wheat in Southwest China.

Building Trust: Children Experiences with Food Allergies at Summer Camp

Introduction: The objective of this study was to explore the experiences and perceptions of children with food allergies at summer camp. Methods: Qualitative draw-and-tell interviews were conducted with 14 food allergic individuals aged 5 - 12 years to capture their lived experience with food allergies at summer camp. Results: Four key interdependent themes: trust, accommodation, proactive parents and coping strategies were identified in how children perceive their food allergies in unregulated summer camp environments.

Vegetarian Diets in Children—Some Thoughts on Restricted Diets and Allergy

Vegetarianism is a common diet worldwide. For a large proportion of people, meat or fish is not available at all or not regularly as a meal. But also in the industrialised countries, vegetarian nutrition is becoming more and more popular for various reasons. Many vegetarian parents also want a suitable diet for their children. But are restrictive diets beneficial or potentially harmful in certain situations, such as a predisposition to severe atopy? Are vegetarian diets equally suitable for pregnant women, nursing mothers, infants, children, and adolescents? What critical nutrients should parents, children, pediatricians, and nutritionists pay particular attention to? This article is focused on questions like these and discusses scientifically based concepts of nutrition. Main findings are that exposure to a variety of food antigens during early life may play a role in the development of healthy eating habits and that restrictive diets have not been found in studies to prevent allergic disease.