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Wheat is a prominent allergenic food that can trigger life-threatening anaphylaxis. Presently, it remains unclear whether wheat glutenin (WG) extract possesses inherent sensitization potential independently, without the use of adjuvants, and whether it can sensitize mice to the extent of inducing life-threatening systemic anaphylaxis. In this study, we tested the hypothesis that repeated skin exposures to WG extract without adjuvant will sensitize mice with the resultant anaphylactic reaction upon systemic WG challenge. Balb/c mice were bred and maintained on a strict plant protein-free diet and were repeatedly exposed to a WG extract or vehicle once a week for 9 weeks. WG-specific (s)IgE and total (t)IgE levels were quantified. Mice were challenged with WG extract to induce anaphylactic reactions as measured by hypothermic shock response (HSR) and mucosal mast cell degranulation response (MMCR). We also conducted proteomic analysis of 120 spleen immune markers. These skin-sensitized mice exhibited exposure-dependent IgE responses and near-fatal anaphylaxis upon challenge. Proteomic analysis identified seven dramatically elevated immune biomarkers in anaphylactic mice. These data reveal that WG is intrinsically allergenic, and that chronic skin exposure to WG extract can prime the mice for potentially fatal anaphylaxis. [ABSTRACT FROM AUTHOR]

IntroductionGluten allergy is a major public health problem that is growing at an alarming rate. Specific mechanisms underlying sensitization to gluten remain incompletely understood. Currently, it is unclear whether chronic exposure to alcohol-soluble gluten extract via undamaged skin has the capacity to clinically sensitize mice for life-threatening anaphylaxis. Using an adjuvant-free mouse model, here we tested the hypothesis that chronic application of alcohol-soluble durum gluten (ASDG) extract will clinically sensitize mice for life-threatening anaphylaxis.MethodsThis study was conducted in a gluten-free Balb/c mouse colony that was established and maintained on a plant protein-free diet. Groups of adult female mice were exposed dermally to ASDG extract or vehicle once a week for 9-weeks. Specific (s) and total (t) IgE levels were quantified. Mice were challenged systemically with ASDG to measure symptoms of systemic anaphylaxis. Hypothermic shock response (HSR) and mucosal mast cell degranulation response (MMCR) were determined upon challenge. Spleen Th1, Th2, and other immune markers were quantified.ResultsWe found that chronic exposure to ASDG elicited robust elevation of sIgE and tIgE. Systemic challenge with ASDG, but not vehicle, elicited life-threatening anaphylaxis associated with dramatic HSR and MMCR. Correlation analysis demonstrated direct positive inter-relationships among IgE, HSR, and MMCR. Anaphylaxis was associated with significant elevation of prototypic Th2 but not Th1 immune markers in the spleen.Discussion/ConclusionOur study collectively demonstrates that ASDG is intrinsically allergenic; and chronic exposure to ASDG via undamaged skin can clinically sensitize mice for life-threatening anaphylaxis via activating the systemic Th2 immune responses.

The risk of developing anaphylactic reactions to medications introduces additional difficulties for effective pharmacotherapy. Using a model of systemic anaphylaxis in mice, we showed that preventive administration of a preparation containing technologically processed antibodies (TPA) to MHC II induces an anti-anaphylactic effect comparable to that of dexamethasone (when assessing the severity of systemic anaphylaxis 30 and 60 min after challenge injection of the model antigen ovalbumin). The revealed activity may be related to the ability of TPA to MHC II to regulate the antigen presentation system and shift the immune response towards the production of IgG instead of IgE typical of anaphylactic reaction. [ABSTRACT FROM AUTHOR]

Wheat is a major food allergen per the regulatory bodies of various nations. Hypersensitivity reactions to wheat have been steadily increasing for reasons that are not completely understood. Wheat-allergy models typically use adjuvants to induce sensitization to wheat proteins followed by an intraperitoneal challenge to elicit anaphylaxis. Although these models are very useful, they lack the ability to reveal the intrinsic allergenicity potential of wheat. To improve the mouse model of wheat allergy, we tested the hypothesis that repeated skin application of salt-soluble protein extract (SSPE) from durum wheat will clinically sensitize the mice to oral anaphylaxis to SSPE. Balb/c mice were bred and maintained on a plant-protein-free diet and used in the experiments. Adult female mice were exposed to SSPE once a week for 9 weeks via a solution on intact skin. Sensitization was measured by SSPE-specific IgE (sIgE) antibody and total IgE (tIgE) levels. Oral anaphylaxis was quantified by hypothermic shock response (HSR), and mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 after oral challenge. Using single mouse data, correlation analyses were performed to determine the relationship among the allergenicity readouts. Spleen cytokines were quantified using a protein microarray method. Our results show that (i) repeated skin exposures to SSPE elicited robust increases in the sIgE and tIgE levels; (ii) skin exposure to SSPE was sufficient to sensitize mice for oral anaphylaxis and MMCR; (iii) both HSR and MMCR showed a strong correlation with each other, as well as with sIgE, and a modest correlation with tIgE levels; (iv) selected Th2/Th17/Th1 cytokines were elevated in skin-sensitized mice; and (v) oral allergen-challenged mice showed selective elevation of IL-6 and a panel of chemokines compared to saline-challenged mice. Together, we report the development and characterization of a novel adjuvant-free wheat-allergy mouse model that uses skin sensitization without tape-stripping followed by oral elicitation of anaphylaxis. Furthermore, validation of quantifiable wheat allergenicity readouts makes this model particularly suitable as a pre-clinical testing tool to assess the intrinsic sensitization/oral-anaphylaxis elicitation potential of novel wheat proteins (e.g., processed wheat) and to develop hypo/non-allergenic wheat products.

Abstract. The study of allergenic properties and immunotoxic effects of the ready-to-use drug form of GSB-106 was carried out. The study of allergenic properties and immunotoxicity of GSB-106 was performed on male albino guinea pigs weighing 250-300 g and on male CBA, C57BL / 6, F1 hybrids (CBAxC57BL / 6) mice. When assessing immunotoxicity, GSB-106 was inject to mice per os for 14 days in doses of 2.2 mg / kg and 22 mg / kg. When studying the allergenicity, GSB-106 was injected to albino guinea pigs in doses of 1 mg / kg and 10 mg / kg according to standard regimens of immunization. The results of the study of the immunotoxicity and allergenicity of GSB-106 allow us to conclude that the injection of the ready-to-use drug form of GSB-106 in the range of studied doses does not have an immunotoxic effect and does not have allergenic properties.

Homeovox, a multicomponent homeopathic treatment for laryngitis of various etiologies, was tested for allergenic properties and immunotoxicity.Methods. 80 male albino guinea pigs and 180 male СВА, C57BL/6 and F1 hybrid (CBAхС57BL/6) mice were used in the study. In order to assess immunotoxicity, Homeovox was administrated orally to mice for 14 days at doses of 100 mg/kg and 1 000 mg/kg. To assess the allergenic properties of Homeovox, albino guinea pigs were also given the drug at doses of 100 mg/kg and 1 000 mg/kg according to the standard immunization schedules.Results. Oral administration of Homeovox to mice for 14 days at doses of 100 mg/kg and 1 000 mg/kg did not cause significant changes in the main characteristics of immune response compared to controls. When assessing allergenicity, Homeovox at doses 100 mg/kg and 1 000 mg/kg administered according to the standard immunization schedules did not induce systemic anaphylaxis or active skin anaphylaxis in albino guinea pigs. The immunization of guinea pigs by Homeovox at the same doses in a mixture with Freund's complete adjuvant caused no delayed allergic reactions. Homeovox at a single oral dose of 1 000 mg/kg significantly decreased concanavalin A-induced inflammation in CBA mice by 58.4 %.Conclusion. Within the dosage range investigated, Homeovox does not induce immunotoxicity, immediate- or delayed-type allergic or pseudoallergic reactions.

Peanut allergy is a major cause of food-induced anaphylaxis and subsequent fatality. Food allergies are becoming an increasingly important global health issue. This study was undertaken to verify the effects of peanut sprout extract (PNSE) on the inhibition of allergic and anaphylactic responses using a peanut (PN)-immunized food allergy mouse model. Fresh peanut sprouts were germinated for 0, 3, 5, and 7 days using mature peanuts. Mice were then sensitized to cholera toxin plus PNE or PNSE by intragastric administration on days 0 and 7, and were then challenged with PNE or PNSE on days 21 and 35. After 5 weeks, we examined the mucosal mast cell degranulation, ear swelling, and systemic anaphylaxis stimulated by PNE extract, in comparison with PNSE. Subsequently, Ara h1, a biomarker of PNE allergy; serum levels; and Th1/Th2 cytokine production in supernatants of cultured splenocytes were measured. PNSE treatment significantly attenuated the secretion of anti-Ara h1 antibody, mucosal mast cell degranulation, degree of systemic anaphylaxis, and ear swelling and increased the production of IFN-γ and IL-10, with a decrease in IL-4 secretion. The results of this study show that the allergenicity of PNE could be reduced by germination, which caused downregulation of Th2 lymphocyte activity, systemic anaphylactic response, and mast cell-mediated ear swelling in PNE-sensitized mice. [ABSTRACT FROM AUTHOR]

The study of allergenic properties and immunotoxic effects of the ready-to-use drug form of GML-1 (N-benzyl-N-methyl-1-phenylpyrrolo[1,2-a] pyrazin-3-carboxamide), compounds with high TSPO affinity and pronounced anxiolytic activity, was carried out. The study of allergenic properties and immunotoxicity of GML-1 was performed on male albino guinea pigs weighing 250-300 g and on male CBA, C57BL / 6, F1 hybrids (CBAxC57BL/6) mice. When assessing immunotoxicity, GML-1 was inject to mice per os for 14 days in doses of 2.2 mg / kg and 22 mg / kg. When studying the allergenicity, GML-1 was injected to albino guinea pigs in doses of 1 mg / kg and 10 mg / kg according to standard regimens of immunization. The results of the study of the immuno-toxicity and allergenicity of GML-1 allow us to conclude that the injection of tablet dosage form of GML-1 in the range of studied doses does not have an immunotoxic effect and allergenic properties.

The development of innovative ingredients of specialized formula for children with intolerance to cow's milk proteins requires accounting the influence of the protein component on the allergic sensitivity. The aim of the research was to study the effect of lactoferrin (LF) from cow colostrum, cow's milk protein hydrolysate (CMPH) and mare's milk protein hydrolysate (MMPH) on the severity of the systemic anaphylaxis reaction, the levels of specific IgG antibodies and cytokines in rats parenterally sensitized with ovalbumin (OVA). Material and methods . The experiment was carried out on 4 groups of 26 male Wistar rats, which were sensitized intraperitoneally with chicken egg OVA and a systemic anaphylaxis reaction was induced on the day 29 by intravenous administration of a challenge dose of the antigen (6 mg per kg body weight). LF, CMPH and MMPH were introduced into the diet in doses of 1.4-2 g/kg body weight per day (on an average 1.59±0.04, 1.53±0.05 and 1.48±0.05 g per kg body weight respectively). The content of IgG antibodies in the blood serum was determined by an indirect ELISA; the levels of cytokines IL-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-10, IL-12(p70), IL-13, GM-CSF, IFN-γ and TNF-α were detected by multiplex immunoassay. Results . Dietary LF did not have a significant effect on the severity of active anaphylactic shock (AAS), concentrations of antibodies and cytokines in the blood of animals. As a result of CMPH consumption, there were no significant changes in AAS severity and IgG antibodies to OVA but significant increase in TNF-α level was observed as well as a significant decrease in IL-1α (p<0.05). In animals receiving MMPH, there were also no significant changes in the severity of AAS, but a 1.9-fold decrease in the level of IgG antibodies to OVA (p<0.001) was noticed along with a significant increase in IL-12(p70) (p<0.05) and IL-10 (p<0.10) level. Conclusion . Cosumption of LF by sensitized rats didn't significantly affect their anaphylactic sensitivity and cytokine profile, while CMPH intake induced some signs of pro-inflammatory processes. Consumption of MMPH was accompanied by the formation of an anti-inflammatory cytokine profile, which corresponds to a decrease in the intensity of the humoral immune response to the model allergen. Differences in the effects of two hydrolisates, which have similar degrees of hydrolysis, may be associated with the specific composition of glycopeptides formed during the enzymatic cleavage of milk protein produced by these two species of dairy animals., Competing Interests: Authors declare no conflict of interests., (Copyright© GEOTAR-Media Publishing Group.)

All three members of the Orai family of cation channels–Orai1, Orai2 and Orai3–are integral membrane proteins that can form store-operated Ca 2+ channels resembling endogenous calcium release-activated channels (CRAC) in many aspects. Loss of function studies in human and murine models revealed many functions of Orai1 proteins not only for Ca 2+ homeostasis, but also for cellular and systemic functions in many cell types. By contrast, the knowledge regarding the contribution of Orai2 and Orai3 proteins in these processes is sparse. In this study, we report the generation of mouse models with targeted inactivation of the Orai2 gene to study Orai2 function in peritoneal mast cells (PMC), a classical cell model for CRAC channels and Ca 2+ -dependent exocytosis of inflammatory mediators. We show that the Ca 2+ rise triggered by agonists acting on high-affinity Fc receptors for IgE or on MAS-related G protein-coupled receptors is significantly increased in Orai2-deficient mast cells. Ca 2+ entry triggered by depletion of intracellular stores (SOCE) is also increased in Orai2 −/− PMCs at high (2 mM) extracellular Ca 2+ concentration, whereas SOCE is largely reduced upon re-addtion of lower (0.1 mM) Ca 2+ concentration. Likewise, the density of CRAC currents, Ca 2+ -dependent mast cell degranulation, and mast cell-mediated anaphylaxis are intensified in Orai2-deficient mice. These results show that the presence of Orai2 proteins limits receptor-evoked Ca 2+ transients, store-operated Ca 2+ entry (SOCE) as well as degranulation of murine peritoneal mast cells but also raise the idea that Orai2 proteins contribute to Ca 2+ entry in connective tissue type mast cells in discrete operation modes depending on the availability of calcium ions in the extracellular space. [ABSTRACT FROM AUTHOR]

Effects of low-dose intraperitoneal injection (6 mgl 120 g rat/day) of lectin from black turtle soup bean (Phaseolus vulgaris) on the anaphylactic reactions in Sprague-Dawly rats were investigated. Sensitization process lastedfor 10 days, and enhanced sensitization was earned out at 14th, 21th and 28th day, respectively. Negative results were obtained in both the Active systemic anaphylaxis test and Passive cutaneous anaphylaxis analysis. Compared with the controls, the changes in the serum IgE level and plasma histamine content obtained in the sensitized rats were not significant measured by ELISA methods. The increase of IL-4 and INF-γ was observed then the antagonism effect of both cytokines was speculated to result in the inconspicuous allergic manifestations. The in vivo results proved that the low-dose intake of black turtle soup bean lectin might not cause a significant allergenicity, and the lectin might be practically applied in the recommended small dosage with respect to its relatively safe biomedical performances in the clinical therapy and drug targeted delivery. [ABSTRACT FROM AUTHOR]

Background: Wheat allergy and other immune-mediated disorders triggered by wheat proteins are growing at an alarming rate for reasons not well understood. A mouse model to study hypersensitivity responses to salt-soluble wheat protein (SSWP) extract is currently unavailable. Here we tested the hypothesis that SSWP extract from wheat will induce sensitization as well as allergic disease in mice. Methods: Female BALB/cJ mice were weaned onto a plant protein-free diet. The mice were injected a total of 4 times with an SSWP (0.01 mg/mouse) fraction extracted from durum wheat along with alum as an adjuvant. Blood was collected biweekly and SSWP-specific IgE (SIgE) and total IgE (TIgE) levels were measured using ELISA. Systemic anaphylaxis upon intraperitoneal injection with SSWP was quantified by hypothermia shock response (HSR). Mucosal mast cell degranulation was measured by the elevation of mMCP-1 in the blood. The mice were monitored for dermatitis. Skin tissues were used in histopathology and for measuring cytokine/chemokine/adhesion molecule levels using a protein microarray system. Results: Injection with SSWP resulted in time-dependent SIgE antibody responses associated with the elevation of TIgE concentration. Challenge with SSWP elicited severe HSR that correlated with a significant elevation of plasma mMCP-1 levels. Sensitized mice developed facial dermatitis associated with mast cell degranulation. Lesions expressed significant elevation of Th2/Th17/Th1 cytokines and chemokines and E-selectin adhesion molecule. Conclusion: Here we report a mouse model of anaphylaxis and atopic dermatitis to SSWP extract that may be used for further basic and applied research on wheat allergy. [ABSTRACT FROM AUTHOR]

Introduction: Gluten allergy is a major public health problem that is growing at an alarming rate. Specific mechanisms underlying sensitization to gluten remain incompletely understood. Currently, it is unclear whether chronic exposure to alcohol-soluble gluten extract via undamaged skin has the capacity to clinically sensitize mice for life-threatening anaphylaxis. Using an adjuvant-free mouse model, here we tested the hypothesis that chronic application of alcohol-soluble durum gluten (ASDG) extract will clinically sensitize mice for life-threatening anaphylaxis., Methods: This study was conducted in a gluten-free Balb/c mouse colony that was established and maintained on a plant protein-free diet. Groups of adult female mice were exposed dermally to ASDG extract or vehicle once a week for 9-weeks. Specific ( s ) and total ( t ) IgE levels were quantified. Mice were challenged systemically with ASDG to measure symptoms of systemic anaphylaxis. Hypothermic shock response (HSR) and mucosal mast cell degranulation response (MMCR) were determined upon challenge. Spleen Th1, Th2, and other immune markers were quantified., Results: We found that chronic exposure to ASDG elicited robust elevation of sIgE and tIgE. Systemic challenge with ASDG, but not vehicle, elicited life-threatening anaphylaxis associated with dramatic HSR and MMCR. Correlation analysis demonstrated direct positive inter-relationships among IgE, HSR, and MMCR. Anaphylaxis was associated with significant elevation of prototypic Th2 but not Th1 immune markers in the spleen., Discussion/conclusion: Our study collectively demonstrates that ASDG is intrinsically allergenic; and chronic exposure to ASDG via undamaged skin can clinically sensitize mice for life-threatening anaphylaxis via activating the systemic Th2 immune responses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (© 2023 Jorgensen, Gao, Chandra, Sundar, Loy, Van Antwerp, Ng and Gangur.)

Objectives: Peanut (PN) allergy is a major public health concern. Recent research has brought clarity about how individuals become sensitized to PN allergen with routes known through the skin, as well as the airway. Still unclear, however, is the role of sex hormones on the development of allergic immune responses to PN. This study examines the role of androgen receptor (AR) signaling in regulating PN-specific immune responses., Methods: We utilized a 4-week inhalation mouse model of PN allergy that is known to drive the production of PN-specific antibodies and elicit systemic anaphylaxis following PN challenge. Wildtype (WT) male, female, and androgen receptor-deficient testicular feminization mutant (AR Tfm ) male mice were examined using this model to document sex differences in PN allergy. To determine if sex differences also existed in the cellular immune response, this study utilized a 3-day inhalation mouse model of PN to examine the response of group 2 innate lymphoid cells (ILC2s). WT male and female mice were examined using this model to document sex differences in ILC2 response within the lungs., Results: AR use is critical in regulating PN-specific antibody levels. We found that AR Tfm males have a higher antibody response and significantly worse anaphylactic response following PN challenge relative to WT males. WT males also exhibit a less severe anaphylactic response compared to AR Tfm male and female mice. Lastly, we discovered that lung ILC2s from female mice respond more robustly to PN compared to ILC2s within WT male mice., Conclusions: Taken together, this study suggests that male sex hormones, namely androgens, negatively regulate allergic immune responses to PN., Competing Interests: None., (AJCEI Copyright © 2023.)

Background: Shellfish (SF) allergy is a leading cause of systemic anaphylaxis in humans. An adjuvant-free mouse model to evaluate allergenicity and oral anaphylaxis to SF is currently unavailable. Here, we tested the hypothesis that transdermal exposure (TDE) to SF protein extract (SFPE) not only elicits a systemic allergic immune response but also will clinically sensitize mice for oral anaphylaxis. Methods: Adult BALB/c female mice (6-8 weeks of age) were exposed to saline or SFPE once a week for 4 weeks using a transder-mal sensitization method. Systemic SF-specific IgE, IgG1 and IgG2a and total (t)IgE responses were measured using ELISA. Systemic anaphylaxis upon oral SFPE administration was assessed according to clinical symptoms and the hypothermia shock response (HSR). Using individual mouse data, the correlation between the readouts of allergenicity was determined using Pearson's analysis. Spleen-cell IL-4 and IFN-γ responses were determined using primary cell culture and ELISA. Results:TDE to SFPE resulted in marked systemic specific (s)IgE, tIgE, IgG1 and IgG2a responses. Oral challenge with SFPE in sensitized mice (but not controls) elicited systemic anaphylactic clinical reactions and HSR. A strong correlation was observed between sIgE, tIgE and HSR. Spleen cells isolated from allergic mice (but not controls) exhibited memory IL-4 and IFN-γ cytokine responses. Conclusion: We report a novel adjuvant-free mouse model of SF allergy with robust quantifiable and correlated readouts of allergenicity that may be used in basic biomedical, preclinical and applied food/nutrition research on SF allergy. [ABSTRACT FROM AUTHOR]

Food allergy is a growing health problem with serious concerns due to high potential for fatality. Rapid advances in the knowledge on causes and mechanisms as well as in developing effective prevention/therapeutic strategies are needed. To meet these goals, mouse models that simulate the human disorder are highly desirable. During the past decade, several mouse models of food allergies have been reported. Here, we briefly reviewed the human disorder and then critically evaluated these models seeking answers to the following important questions: To what extent do they simulate the human disorder? What are the strengths and limitations of these models? What are the challenges facing this scientific area? Our analysis suggest that: (i) the mouse models, with inherent strengths and limitations, are available for many major food allergies; there is scope for additional model development and validation; (ii) models mostly simulate the severe forms of human disorder with similar immune and clinical features; (iii) the approaches used to develop some of the mouse models may be questionable; and (iv) the specific mechanisms of sensitization as wells as oral elicitation of fatal reactions in both humans and mice remains incompletely understood and therefore warrants further research. [ABSTRACT FROM AUTHOR]

The effect of Bauhinia variegata (Caesalpiniaceae) stem bark extracts on mast cell stabilizing activity was investigated to explore the scientific basis for the use of the decoction of its stem bark in the treatment of asthma and other respiratory complications in traditional Ayurvedic system of medicine. The authenticated plant material was defatted using petroleum ether and extracted with ethanol and distilled water to obtain ethanol (BVE) and aqueous (BVA) extract, respectively. The stabilization potential was studied on mouse mast cells and anti-anaphylactic activity was evaluated by determining the mortality rate of mice treated with toxicant (compound 48/80). The BVE (400 mg.kg-1) significantly protected mast cell from degranulation (71.18%) and reduced the mortality (50%) when compared to standard drug disodium cromoglycate (DSCG) used in the study. BVE possessed potent mast cell stabilizing activity, suggesting potential for use in the treatment of asthma. [ABSTRACT FROM AUTHOR]

Context: Decoctions of Baliospermum montanum Müll. Arg. (Euphorbiaceae) leaves are reported to be useful in the treatment of asthma and other respiratory complications in the Ayurvedic system. Objective: To evaluate the mast cell stabilization and antihistaminic activities of the chloroform (BMLC) and ethanol (BMLE) extracts of the leaves of Baliospermum montanum. Materials and methods: The stabilization potential was studied on mouse peritoneal mast cells and the antihistaminic activity was carried out by determining the mortality rate of mice treated with toxicant (compound 48/80) and the effect on elevation of histamine release upon degranulation. Results: The increased number of intact mast cells (43.640 ± 1.7% and 61.57 ± 1.79% at 200 and 400 mg/ kg, respectively) suggested that the BMLC stabilized the mast cell degranulation and showed decreased elevation of histamine. Conclusion: BMLC extract was found to be most effective against degranulation and release of histamine from mast cells. Identifying the lead from this plant will be a definite target for treating allergic diseases. [ABSTRACT FROM AUTHOR]

Background: Clinically it is recognized that tree nut allergies such as hazelnut allergy are not usually outgrown. Specific mechanisms underlying the persistence of such food allergies are incompletely understood. Here we studied the natural history and the long-term immune and clinical characteristics of hazelnut allergy in an adjuvant-free mouse model. Methods: BALB/c mice were sensitized to hazelnut protein using a transdermal sensitization protocol that does not use adjuvant. After establishing sensitization, exposure to hazelnut was withdrawn for 3, 5 or 8 months. The fate of circulating IgE antibodies was monitored. Subsequently, mice were given booster exposures and examined for memory IgE antibody and spleen cell IL-4 responses. Clinical characteristics and hypothermia responses upon oral allergen challenge were studied. Results: Upon allergen withdrawal, circulating hazelnut-specific IgE antibody levels began to drop. Nevertheless, IgE responses once established remained at significantly high levels for up to 8 months (the last time point studied) despite withdrawal of allergen exposure. Memory IgE responses to booster exposures were robust after 3, 5 or 8 months of allergen withdrawal. Furthermore, significant clinical reactivity to oral hazelnut challenge, and hypothermia responses were demonstrable at each of these time points. Long-lasting spleen cell memory IL-4 responses to hazelnut were detectable in these mice explaining the mechanism of sustenance of IgE responses and clinical sensitization. Conclusions: Hazelnut allergy once established persists for long periods, despite withdrawal of allergen exposure, due to long-lasting, memory IgE and IL-4 responses. Copyright © 2010 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Milk allergy is the most common type of food allergy in humans with the potential for fatality. An adjuvantfree mouse model would be highly desirable as a preclinical research tool to develop novel hypoallergenic or nonallergenic milk products. Here we describe an adjuvant-free mouse model of milk allergy that uses transdermal sensitization followed by oral challenge with milk protein. Groups of BALB/c mice were exposed to milk whey protein via a transdermal route, without adjuvant. Systemic IgG1 and IgE antibody responses to transdermal exposure as well as systemic anaphylaxis and hypothermia response to oral protein challenge were studied. Transdermal exposure resulted in a time- and dose-dependent induction of significant IgE and IgG1 antibody responses. Furthermore, oral challenge of sensitized mice resulted in significant clinical symptoms of systemic anaphylaxis within 1 h and significant hypothermia at 30 min postchallenge. To study the underlying mechanism, we examined allergendriven spleen cell T-helper 2 cytokine (IL-4) responses. There was a robust dose- and time-dependent activation of memory IL-4 responses in allergic mice but not in healthy control mice. These data demonstrate for the first time a novel transdermal sensitization followed by oral challenge mouse model of milk allergy that does not use adjuvant. It is expected that this model may be used not only to study mechanisms of milk allergy, but also to evaluate novel milk products for allergenic potential and aid in the production of hypo- or nonallergenic milk products. [ABSTRACT FROM AUTHOR]

Background: Cashew nut allergy is an emerging food allergy with a high risk of systemic anaphylaxis. Currently, an adjuvant-free animal model to study cashew nut allergy is not available. Methods: BALB/c mice were exposed to cashew nut protein using a transdermal sensitization protocol that does not use adjuvant. Systemic IgE antibody response, systemic anaphylaxis to oral challenge and allergen-driven, spleen-cell, type-2 cytokine responses were studied. Results: Transdermal exposure to cashew nut resulted in a significant dose-dependent allergic response. Oral challenge of sensitized mice with cashew resulted in severe signs of systemic anaphylaxis and a significant hypothermia. Spleen cell culture with cashew nut protein resulted in allergen-driven IL-4, IL-5 and IL-13 responses only in sensitized but not in saline control mice. Conclusions: These data demonstrate that (i) transdermal exposure to cashew nut protein elicits a robust IgE response leading to clinical sensitization of mice for systemic anaphylaxis to oral cashew nut challenge; (ii) cashew nut is a potent activator of type-2 cytokines, thus explaining the mechanism of cashew allergy, and (iii) this mouse model may be useful for further basic and preclinical studies on cashew nut allergy. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background: Tree nut allergy, a major group of food allergy, is often linked to fatal or near-fatal systemic anaphylaxis. Currently, an adjuvant-free mouse model to study tree nut hypersensitivity is unavailable. Here we tested the hypothesis that transdermal exposure to hazelnut, a model tree nut, without the use of an adjuvant is sufficient to sensitize mice for immediate hypersensitivity reaction to oral hazelnut challenge. Methods: BALB/c mice were repeatedly exposed to hazelnut protein via the transdermal route and systemic allergic and anaphylactic responses were studied. Results: Transdermal exposure to hazelnut protein elicited robust systemic IgE response in a dose-dependent manner with immunological memory. Oral challenge of transdermally sensitized mice with hazelnut protein resulted in immediate (30 min after the challenge) clinical signs of systemic anaphylaxis as measured by significant clinical scores and drop in rectal temperature. Clinical hypersensitivity reaction was associated with severe pathological changes in the small intestine. Hazelnut-allergic but not control mice exhibited in vivo activation of GATA-3 and hazelnut-driven recall IL-4, IL-5 and IL-13 response by splenocytes, thus elucidating the underlying mechanism of hazelnut allergy development in this model. Conclusions: These data suggest that (1) transdermal exposure to hazelnut protein is sufficient to activate the key immune pathways necessary for sensitizing mice for clinical immediate hypersensitivity reactions and (2) this mouse model may be useful for further basic and applied studies on tree nut allergy, especially because it does not depend on an adjuvant for eliciting immediate hypersensitivity reactions to nut protein. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Background Immunological oral tolerance is being studied with great interest due to its therapeutic potential in allergy and autoimmunity processes, although the cellular and molecular mechanisms linking these different phenomena remain elusive. In the present study, two mouse lines with extreme phenotypes for susceptibility [TS Line] or resistance [TR Line] to oral tolerance and their [TS × TR]F2 segregants were used in order to evaluate the impact of these traits on the atopic potential of the individuals. Objective Demonstrate whether the tr and ts genes, cumulated during 18 generations of bidirectional genetic selection, influence expression of two important immunobiological traits (IgE and mast cell) critical to allergic response. Methods Mice with extreme phenotypes for oral tolerance to ovalbumin (OVA), produced by assortative mating (TS and TR Line), and their (TS × TR)F2 segregating were used. Serum IgE levels assayed by ELISA, and mastocytes counted with toluidine blue staining were evaluated in naïve mice. Anaphylaxis was induced by intravenous injection of OVA, intestinal inflammation by oral administration of OVA 7 days after immunization, and pulmonary inflammation by intranasal and nebulization OVA challenges. Specific IgE was dosed by passive cutaneous anaphylaxis. Results The naïve TS mice have a 20-fold lower serum IgE level and two- to threefold diminished mast cell numbers in mucosal sites, when compared with TR-mice, which were highly susceptible to allergic inflammation and anaphylactic shock. The associations of oral tolerance, serum IgE levels and mast cell numbers in naïve animals were confirmed analysing the simultaneous presence of these traits in individuals of a [TS × TR]F2-segregating population. Conclusion The results suggest that the complex of genes controlling TS and TR phenotypes play a main role in the regulation of the atopic potential of the individual. The studies of these traits in interline F2 segregants demonstrated a co-segregation of TS and TR phenotypes with IgE responsiveness and mast cell numbers. Thus, the opposite capacity of the genetically modified mice may be involved in co-adaptative mechanisms reflecting a dynamic relation between gene frequencies in a natural population. These correlations give circumstantial evidence to support clinical applications of oral tolerance in allergic and autoimmune diseases. [ABSTRACT FROM AUTHOR]

Abstract: The effects of extracts from various oriental medicinal herbs on mast cell-mediated allergic reaction were investigated. Among them, Chrysanthemi sibirici herba ethanol extract exerted the potent inhibitory activity on antigen-induced degranulation in RBL-2H3 mast cells. Chrysanthemi sibirici herba dose-dependently inhibited DNP–BSA or compound 48/80-induced degranulation in RBL-2H3 mast cells, with IC50 values of approximately 49μg/ml and 76μg/ml, respectively. This extract strongly suppressed compound 48/80-induced systemic anaphylaxis by 48.7% at a dose of 300mg/kg in mice. Chrysanthemi sibirici herba also inhibited the expression of TNF-α and the activation of the MAP kinase, ERK1/2, which is critical for the production of inflammatory cytokines in mast cells, as indicated by the suppression of activating phosphorylation of ERK1/2. These results lead us to conclude that Chrysanthemi sibirici herba may be used clinically to treat various allergic diseases. [Copyright &y& Elsevier]

The effect of aqueous extract of Xanthii fructus (XF) on mast cell-mediated allergic reaction has been investigated. XF inhibited compound 48/80-induced systemic anaphylaxis in mouse. This dose-dependently inhibited histamine release from rat peritoneal mast cells (RPMC) by compound 48/80. Additionally, XF inhibited local immunoglobulin E (IgE)-mediated passive cutaneous anaphylatic reaction. When XF (0.1 mg/ml) was added, the secretion of tumor necrosis factor-α (TNF-α) from anti-dinitrophenyl (DNP) IgE antibody-stimulated mast cells was inhibited by 56%. Our studies provide evidence that XF may be beneficial in the treatment of various types allergic diseases. [Copyright &y& Elsevier]

This study was undertaken to examine whether glucocorticoids could be implicated in the hyporesponsiveness of diabetic rats to systemic anaphylaxis. Rats were actively sensitized with a mixture of Al(OH)3 plus ovalbumin and challenged i.v. with ovalbumin 14 days later. Diabetes was induced by alloxan-injected i.v. either before or after sensitization. Elevation of total and specific serum immunoglobulin E (IgE) was abolished in rats turned diabetic and then sensitised, but not in those first sensitised and then turned diabetic. In both conditions, increased serum corticosterone levels occurred in parallel with protection of diabetic animals against fatal shock, intestinal haemorrhage and elevation in plasma histamine levels evoked by antigen challenge. The resistance of diabetic rats to fatal shock was no longer significantly different from that of non-diabetic rats following treatment with the glucocorticoid receptor antagonist RU 486 (mifepristone). These findings indicate that endogenous glucocorticoid plays a pivotal role in the phenomenon of hyporeactivity to systemic anaphylaxis in alloxan-diabetic rats. [Copyright &y& Elsevier]

Wheat is a major food allergen per the regulatory bodies of various nations. Hypersensitivity reactions to wheat have been steadily increasing for reasons that are not completely understood. Wheat-allergy models typically use adjuvants to induce sensitization to wheat proteins followed by an intraperitoneal challenge to elicit anaphylaxis. Although these models are very useful, they lack the ability to reveal the intrinsic allergenicity potential of wheat. To improve the mouse model of wheat allergy, we tested the hypothesis that repeated skin application of salt-soluble protein extract (SSPE) from durum wheat will clinically sensitize the mice to oral anaphylaxis to SSPE. Balb/c mice were bred and maintained on a plant-protein-free diet and used in the experiments. Adult female mice were exposed to SSPE once a week for 9 weeks via a solution on intact skin. Sensitization was measured by SSPE-specific IgE (sIgE) antibody and total IgE (tIgE) levels. Oral anaphylaxis was quantified by hypothermic shock response (HSR), and mucosal mast cell response (MMCR) was quantified by measuring MMCP-1 after oral challenge. Using single mouse data, correlation analyses were performed to determine the relationship among the allergenicity readouts. Spleen cytokines were quantified using a protein microarray method. Our results show that (i) repeated skin exposures to SSPE elicited robust increases in the sIgE and tIgE levels; (ii) skin exposure to SSPE was sufficient to sensitize mice for oral anaphylaxis and MMCR; (iii) both HSR and MMCR showed a strong correlation with each other, as well as with sIgE, and a modest correlation with tIgE levels; (iv) selected Th2/Th17/Th1 cytokines were elevated in skin-sensitized mice; and (v) oral allergen-challenged mice showed selective elevation of IL-6 and a panel of chemokines compared to saline-challenged mice. Together, we report the development and characterization of a novel adjuvant-free wheat-allergy mouse model that uses skin sensitization without tape-stripping followed by oral elicitation of anaphylaxis. Furthermore, validation of quantifiable wheat allergenicity readouts makes this model particularly suitable as a pre-clinical testing tool to assess the intrinsic sensitization/oral-anaphylaxis elicitation potential of novel wheat proteins (e.g., processed wheat) and to develop hypo/non-allergenic wheat products., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Gao, Jorgensen, Raghunath, Ng and Gangur.)

We have established transgenic mice that carry the genes coding for heavy and light chains of TNP-specific IgE. They produced high titers of TNP-specific IgE (20–40 μg/ml in serum) and their mast cells were heavily loaded with IgE. The level of FcεRI expression on their mast cells was 6–8 times higher than that in non-transgenic littermates. The expression of low-affinity IgE receptor FcεRII (CD23) on splenic B cells was also 6–8 times higher in the transgenic mice. Consistent with this, substantial amounts of IgE were detected on B cells in the transgenic mice. When challenged with i.v. administration of the corresponding antigen, the transgenic mice exhibited systemic anaphylactic symptoms such as a drastic drop of body temperature and extravasation of administered dye. Biphasic (immediate and delayed) ear swelling response was also elicited in a TNP-specific manner by epicutaneous antigen challenge without any prior sensitization. Thus, IgE produced in the transgenic mice was found to be biologically active to induce both local and systemic allergic reactions in vivo upon the challenge of the corresponding antigen. Taken together, the antigen-specific IgE transgenic mice established for the first time in this study appear to provide an attractive model system to study the pathological roles of IgE in acute and chronic phases of allergic inflammation as well as their immunobiological roles in vivo. They may also be useful to develop novel therapeutic strategies for atopic disorders. [ABSTRACT FROM PUBLISHER]

The aqueous extract of Siegesbeckia pubescens (SPAE) inhibited compound 48/80-induced systemic anaphylaxis 100% with the dose of 1.0, 0.5 mg/g body weight (BW) at 1 h before or 5 min, 10 min after intraperitoneal injection of compound 48/80. The passive cutaneous anaphylaxis (PCA) reaction also inhibited to 78.5% by oral administration of SPAE (1.0 mg/g BW). When SPAE pretreated on mice at concentrations ranging from 0.0001 to 1.0 mg/g BW, the serum histamine levels were reduced in a dose-dependent manner. Moreover, SPAE (100–800 μg/ml) dose-dependently inhibited the histamine release from peritoneal mast cells (RPMC) by compound 48/80 (5 μg/ml). Analysis by microscopic appearance observation revealed that SPAE (500 μg/ml) stabilized the RPMC membrane. Therefore, these findings indicate that SPAE inhibits anaphylactic reactions through stabilization of mast cell membrane. [ABSTRACT FROM AUTHOR]