Assessment of the allergic potential of food protein extracts and proteins on oral application using the brown Norway rat model.

The need for widely accepted and validated animal models to test the potential allergenicity and potency of novel (biotechnology-derived) proteins has become an important issue for their safety evaluation. In this article, we summarize the results of the development of an oral sensitization protocol for food proteins in the rat. Young Brown Norway rats were exposed to either various purified allergenic proteins (e.g., ovalbumin, partly purified), a whole food (cow's milk), or total protein extracts (hen's egg white, peanut) by daily gavage dosing during 42 days without the use of an adjuvant. The results showed that Brown Norway rats can be sensitized orally to the various allergenic food proteins tested, resulting in antigen-specific immunoglobulin (Ig) G and IgE responses, without the use of adjuvants. Animals orally exposed to cow's milk or total protein extracts of egg white also developed specific IgE and IgG antibodies that recognized the same proteins compared with antibodies from patients allergic to egg white or cow's milk. We also studied local and systemic immune-mediated effects. In ovalbumin-sensitized rats, some clinical symptoms of food allergy were studied upon an oral challenge with ovalbumin. The results demonstrated that gut permeability was increased and that in some animals breathing frequency and systolic blood pressure were temporarily decreased. The results obtained show that the Brown Norway rat provides a suitable animal model for food allergy research and for the study of relative allergenicity of existing and novel food proteins

Serum biomarkers for allergy in children

A large number of studies investigating various biomarkers for allergy have been published over the past decades. The aim of this review was to evaluate these biomarkers on their diagnostic and/or predictive value. To this date, no single or specific biomarker for allergy has been identified. As allergy is not one disease, but a collection of a number of allergic conditions, it is more plausible a combination of clinical history, clinical readouts, and diagnostic markers will be needed

Особенности трансформации символа креста на территории средневековой Таврики

BACKGROUND: Cow's milk-derived whey hydrolysates are nutritional substitutes for allergic infants. Safety or residual allergenicity assessment of these whey hydrolysates is crucial. Currently, rat basophilic leukemia RBL-2H3 cells expressing the human IgE receptor α-chain (huFcεRIα-RBL-2H3), sensitized with serum IgE from cow's milk allergic children, are being employed to assess in vitro residual allergenicity of these whey hydrolysates. However, limited availability and inter-lot variation of these allergic sera impede standardization of whey hydrolysate safety testing in degranulation assays. OBJECTIVE: An oligoclonal pool of chimeric human (chu)IgE antibodies against bovine β-lactoglobulin (a major allergen in whey) was generated to increase sensitivity, specificity, and reproducibility of existing degranulation assays. METHODS: Mice were immunized with bovine β-lactoglobulin, and subsequently the variable domains of dissimilar anti-β-lactoglobulin mouse IgG antibodies were cloned and sequenced. Six chimeric antibodies were generated comprising mouse variable domains and human constant IgE/κ domains. RESULTS: After sensitization with this pool of anti-β-lactoglobulin chuIgEs, huFcεRIα-expressing RBL-2H3 cells demonstrated degranulation upon cross-linking with whey, native 18 kDa β-lactoglobulin, and 5-10 kDa whey hydrolysates, whereas a 3 kDa whey hydrolysate and cow's milk powder (mainly casein) showed no degranulation. In parallel, allergic serum IgEs were less sensitive. In addition, our pool anti-β-lactoglobulin chuIgEs recognized multiple allergenic immunodominant regions on β-lactoglobulin, which were also recognized by serum IgEs from cow's milk allergic children. CONCLUSION: Usage of our 'unlimited' source and well-defined pool of β-lactoglobulin-specific recombinant chuIgEs to sensitize huFcεRIα on RBL-2H3 cells showed to be a relevant and sensitive alternative for serum IgEs from cow's milk allergic patients to assess safety of whey-based non-allergic hydrolyzed formula

Development of ranking system for higher education of Ukraine

A system of determination of university ranking in Ukraine was developed based on the creation of the corresponding methods adequate to the structure, peculiarities and conditions of the Ukrainian universities functioning. A complex of organizational and program-technical means was proposed for collection of the necessary data and determination of university rankings. For specialists in the field of higher education management, those seeking for higher education and employers.Разработана система определения рейтингов университетов Украины, которая основывается на создании определенной методики, адекватной структуре, особенностям и условиям функционирования отечественной высшей школы. Предложен комплекс организационных и программно-технических средств, который применяется при сборе данных и определении оценок рейтингов университетов для специалистов в области управления высшим образованием, а также желающих получить образование и работодателей.Розроблено систему визначення рейтингів університетів України, яка ґрунтується на створенні відповідної методики, адекватної до структури, особливостей та умов функціонування вітчизняної вищої школи. Запропоновано комплекс організаційних і програмно-технічних засобів, що застосовується при збиранні даних та визначенні оцінок рейтингів університетів для фахівців у галузі управління вищою освітою, а також бажаючих отримати освіту та роботодавців

Improved Efficacy of Oral Immunotherapy Using Non-Digestible Oligosaccharides in a Murine Cow’s Milk Allergy Model: A Potential Role for Foxp3+ Regulatory T Cells

BackgroundOral immunotherapy (OIT) is a promising therapeutic approach to treat food allergic patients. However, there are some concerns regarding its safety and long-term efficacy. The use of non-digestible oligosaccharides might improve OIT efficacy since they are known to directly modulate intestinal epithelial and immune cells in addition to acting as prebiotics.AimTo investigate whether a diet supplemented with plant-derived fructo-oligosaccharides (FOS) supports the efficacy of OIT in a murine cow’s milk allergy model and to elucidate the potential mechanisms involved.MethodsAfter oral sensitization to the cow’s milk protein whey, female C3H/HeOuJ mice were fed either a control diet or a diet supplemented with FOS (1% w/w) and received OIT (10 mg whey) 5 days a week for 3 weeks by gavage. Intradermal (i.d.) and intragastric (i.g.) challenges were performed to measure acute allergic symptoms and mast cell degranulation. Blood and organs were collected to measure antibody levels and T cell and dendritic cell populations. Spleen-derived T cell fractions (whole spleen- and CD25-depleted) were transferred to naïve recipient mice to confirm the involvement of regulatory T cells (Tregs) in allergy protection induced by OIT + FOS.ResultsOIT + FOS decreased acute allergic symptoms and mast cell degranulation upon challenge and prevented the challenge-induced increase in whey-specific IgE as observed in sensitized mice. Early induction of Tregs in the mesenteric lymph nodes (MLN) of OIT + FOS mice coincided with reduced T cell responsiveness in splenocyte cultures. CD25 depletion in OIT + FOS-derived splenocyte suspensions prior to transfer abolished protection against signs of anaphylaxis in recipients. OIT + FOS increased serum galectin-9 levels. No differences in short-chain fatty acid (SCFA) levels in the cecum were observed between the treatment groups. Concisely, FOS supplementation significantly improved OIT in the acute allergic skin response, %Foxp3+ Tregs and %LAP+ Th3 cells in MLN, and serum galectin-9 levels.ConclusionFOS supplementation improved the efficacy of OIT in cow’s milk allergic mice. Increased levels of Tregs in the MLN and abolished protection against signs of anaphylaxis upon transfer of CD25-depleted cell fractions, suggest a role for Foxp3+ Tregs in the protective effect of OIT + FOS

Dietary Intervention with β-Lactoglobulin-Derived Peptides and a Specific Mixture of Fructo-Oligosaccharides and Bifidobacterium breve M-16V Facilitates the Prevention of Whey-Induced Allergy in Mice by Supporting a Tolerance-Prone Immune Environment

Cow’s milk allergy (CMA) prevails in infants and brings increased risk of developing other allergic diseases. Oral administration of specific β-lactoglobulin (BLG)-derived peptides (PepMix) and a specific blend of short- and long-chain fructo-oligosaccharides and Bifidobacterium breve M-16V (FF/Bb) was found to partially prevent CMA development in mice. In this study, we aimed to expand the knowledge on the preventive potential and the underlying mechanisms of this approach. Three-week-old female C3H/HeOuJ mice were orally exposed to PepMix±FF/Bb prior to a 5-week oral sensitization with whole whey and cholera toxin as an adjuvant. The acute allergic skin response was determined after an intradermal challenge with whole whey protein. Following an oral challenge with whey, regulatory T cells (Tregs) in the small intestine lamina propria (SI-LP) and mRNA expression of immune markers in the Peyer’s patches (PP) were investigated. The early impact of PepMix and FF/Bb interventions on the immune system during the oral tolerance (OT) induction phase was investigated after the last OT administration. Pre-exposing mice to PepMix+FF/Bb partially prevented the acute allergic skin response compared to PBS and increased Tregs and activated T cells in the SI-LP compared to sham-sensitized mice. It also increased the mRNA expression of Tbet over GATA3 in the PP of whey-sensitized mice. Directly upon the 6-day OT phase, FF/Bb intervention enhanced cecal content levels of propionic and butyric acid in PepMix-fed mice and the former was positively correlated with Foxp3+ cell numbers in the colon. In the PP of PepMix+FF/Bb-exposed mice, IL-22 mRNA expression increased and IL-10 followed the same tendency, while the Foxp3 expression was increased over GATA3 and RorγT. In the colon, the Tbet mRNA expression increased over GATA3, while IL-22 decreased. In addition, the Foxp3+/GATA3+ and regulatory/effector T cell ratios in the mesenteric lymph nodes and the CD11b+/CD11b− conventional dendritic cells ratio in the SI-LP were increased. In conclusion, the FF/Bb diet facilitates the capacity of the specific BLG-peptides to partially prevent the allergic response after sensitization to whole whey protein, possibly by creating a tolerance-prone environment during the OT phase. Such a dietary intervention might contribute to tailoring successful strategies for CMA prevention

A specific mixture of non-digestible oligosaccharides enhances the tolerizing capacity of a partial whey hydrolysate in a mouse model for cow's milk allergy

Hypoallergenic infant formulas (HA) are considered a good alternative for infants at high risk for developing allergy if breastfeeding is not possible. Dietary intervention studies with HA combined with a specific mixture of non-digestible oligosaccharides, have been shown to reduce allergic symptoms in these children. However, the mechanisms by which these oligosaccharides exert their effect are yet to be explored. In this study, the contribution of this specific oligosaccharides mixture on the tolerizing capacity of a partial whey hydrolysate (WH) was investigated in a mice model of cow's milk allergy. Mice were sensitized orally with whey using cholera toxin as adjuvant. Prior to sensitization mice were pre-treated orally with partial WH, PBS, with or without supplementation with the specific oligosaccharide mixture containing short chain-galacto-, long chain-fructo- and acidic-oligosaccharides (9:1:1). After challenge, the acute allergic skin response, the mast cell mediator mMCP-1 and whey-specific antibodies were measured. The presence of Foxp3+regulatory T-cells and CD103+DC were determined in mesenteric lymph nodes. Oral pre-treatment of mice fed the partial WH induced tolerance as refl ected by a reduced acute allergic skin response and a suppressed mMCP-1 release without affecting whey-specific IgE levels. This effect coincided with increased CD103+DC and Foxp3+regulatory T-cell numbers. Interestingly, a combination of the partial WH and oligosaccharide diet completely abolished the acute allergic skin response and mMCP-1 release. In addition, a tendency towards decreased IgE levels and a further increase in intestinal CD103+DC numbers was observed. A specific mixture of non-digestible oligosaccharides enhanced the capacity of a partial WH to induce oral tolerance. This effect was associated with increased numbers of CD103+DC in the mesenteric lymph nodes, suggesting a role of these cells in the observed tolerance inducing capacity of this specific oligosaccharide mixture combined with partial WH

The efficacy of oral and subcutaneous antigen-specific immunotherapy in murine cow's milk- and peanut allergy models

From Pubmed: " BACKGROUND: Antigen-specific immunotherapy (AIT) is a promising therapeutic approach for both cow's milk allergy (CMA) and peanut allergy (PNA), but needs optimization in terms of efficacy and safety. AIM: Compare oral immunotherapy (OIT) and subcutaneous immunotherapy (SCIT) in murine models for CMA and PNA and determine the dose of allergen needed to effectively modify parameters of allergy. METHODS: Female C3H/HeOuJ mice were sensitized intragastrically (i.g.) to whey or peanut extract with cholera toxin. Mice were treated orally (5 times/week) or subcutaneously (3 times/week) for three consecutive weeks. Hereafter, the acute allergic skin response, anaphylactic shock symptoms and body temperature were measured upon intradermal (i.d.) and intraperitoneal (i.p.) challenge, and mast cell degranulation was measured upon i.g. challenge. Allergen-specific IgE, IgG1 and IgG2a were measured in serum at different time points. Single cell suspensions derived from lymph organs were stimulated with allergen to induce cytokine production and T cell phenotypes were assessed using flow cytometry. RESULTS: Both OIT and SCIT decreased clinically related signs upon challenge in the CMA and PNA model. Interestingly, a rise in allergen-specific IgE was observed during immunotherapy, hereafter, treated mice were protected against the increase in IgE caused by allergen challenge. Allergen-specific IgG1 and IgG2a increased due to both types of AIT. In the CMA model, SCIT and OIT reduced the percentage of activated Th2 cells and increased the percentage of activated Th1 cells in the spleen. OIT increased the percentage of regulatory T cells (Tregs) and activated Th2 cells in the MLN. Th2 cytokines IL-5, IL-13 and IL-10 were reduced after OIT, but not after SCIT. In the PNA model, no differences were observed in percentages of T cell subsets. SCIT induced Th2 cytokines IL-5 and IL-10, whereas OIT had no effect. CONCLUSION: We have shown clinical protection against allergic manifestations after OIT and SCIT in a CMA and PNA model. Although similar allergen-specific antibody patterns were observed, differences in T cell and cytokine responses were shown. Whether these findings are related to a different mechanism of AIT in CMA and PNA needs to be elucidated.