Circulating Ara h 6 as a marker of peanut protein absorption in tolerant and allergic humans following ingestion of peanut-containing foods.

Background: Bioaccessibility of food allergens may be a key determinant of allergic reactions.

Objective: To develop a protocol allowing the detection of the major peanut allergen, Ara h 6, in the bloodstream following ingestion of low amounts of peanut and to compare Ara h 6 bioaccessibility by food matrix. We further assessed for differences in absorption in healthy versus peanut-allergic volunteers.

Deep analysis of immune response and metabolic signature in children with food protein induced enterocolitis to cow's milk.

Background: Food Protein-Induced Enterocolitis Syndrome (FPIES) is considered to be a non-IgE mediated food allergy. However, its pathogenesis remains poorly understood and biomarkers are lacking. We aimed to perform in-depth characterization of humoral and cellular immune responses in children with cow's milk (CM)-FPIES and investigated whether there is a FPIES metabolomic signature.

Further studies on the biological activity of hazelnut allergens.

Background: Sensitization to hazelnut allergens vary depending on the geographic origin and age of the patients. The objective of this study was to further investigate the allergenic activity of hazelnut allergens using sera from patients recruited in various European regions and presenting different sensitization patterns to hazelnut proteins.

Methods: Natural Cor a 11 and Cor a 9 were purified from hazelnut whereas Cor a 1 and Cor a 8 were produced as recombinant proteins (rCor a 1.

Peanut allergens are rapidly transferred in human breast milk and can prevent sensitization in mice.

Background: Food allergens have been evidenced in breast milk under physiological conditions, but the kinetic and the role of this passage in food allergies are still unclear. We then aimed to analyze the passage of peanut allergens in human breast milk and their allergenicity/immunomodulatory properties.

Methods: Human breast milk was collected from two non-atopic peanut-tolerant mothers before and at different time points after ingestion of 30 g of commercial roasted peanut.

Goat's milk allergy without cow's milk allergy: suppression of non-cross-reactive epitopes on caprine β-casein.

Background And Objective: Goat's milk (GM) allergy associated with tolerance to cow's milk (CM) has been reported in patients without history of CM allergy and in CM-allergic children successfully treated with oral immunotherapy. The IgE antibodies from GM-allergic/CM-tolerant patients recognize caprine β-casein (βcap) without cross-reacting with bovine β-casein (βbov) despite a sequence identity of 91%. In this study, we investigated the non-cross-reactive IgE-binding epitopes of βcap.

Immunomodulatory potential of partially hydrolyzed β-lactoglobulin and large synthetic peptides.

The immunomodulatory potential of fragments derived from the cow's milk allergen bovine β-lactoglobulin (BLG) was assessed in a mouse model of oral tolerance (OT) [Adel-Patient, K.; Wavrin, S.; Bernard, H.

Specificity of IgE antibodies from patients allergic to goat's milk and tolerant to cow's milk determined with plasmin-derived peptides of bovine and caprine β-caseins.

Scope: Despite a sequence homology of 90% between bovine and caprine β-caseins (CN), IgE antibodies from patients allergic to goat's milk (GM), but tolerant to cow's milk (CM), recognize caprine β-CN without cross-reacting with bovine β-CN. We investigated this lack of cross-reactivity by evaluating the IgE-reactivity toward peptides isolated from plasmin hydolysates of bovine and caprine β-CN.

Methods And Results: The IgE-binding capacity of plasmin-derived peptides was evaluated with sera from 10 CM-allergic patients and 12 GM-allergic/CM-tolerant patients.

Oral tolerance and Treg cells are induced in BALB/c mice after gavage with bovine β-lactoglobulin.

Background: Food allergy is considered as resulting from an impaired development or a breakdown of oral tolerance. We aimed to induce oral tolerance to the major cow's milk allergen bovine β-lactoglobulin (BLG) or corresponding trypsin hydrolysates (BLG-Try) and to investigate the mechanisms involved.

Methods: Wild-type BALB/cJ mice were gavaged on days 1-3 and 8-10 with different doses of native BLG (nBLG) or with nBLG-Try and were then sensitized on day 14 by i.

Immunological and metabolomic impacts of administration of Cry1Ab protein and MON 810 maize in mouse.

We have investigated the immunological and metabolomic impacts of Cry1Ab administration to mice, either as a purified protein or as the Cry1Ab-expressing genetically modified (GM) MON810 maize. Humoral and cellular specific immune responses induced in BALB/cJ mice after intra-gastric (i.g.

Block copolymers have differing adjuvant effects on the primary immune response elicited by genetic immunization and on further induced allergy.

Block copolymers were recently used to promote gene delivery in various tissues. Using a plasmid encoding a food allergen, bovine beta-lactoglobulin (BLG), we studied the effects of block copolymers on gene expression levels and primary immune response and on further induced allergy. Block copolymers (i.

Influence of the route of administration on immunomodulatory properties of bovine beta-lactoglobulin-producing Lactobacillus casei.

Because of their intrinsic immunomodulatory properties, some lactic acid bacteria were reported to modulate allergic immune responses in mice and humans. We recently developed recombinant strains of Lactobacillus casei that produce beta-lactoglobulin (BLG), a major cow's milk allergen. Here, we investigated immunomodulatory potency of intranasal and oral administrations of recombinant lactobacilli on a subsequent sensitization of mice to BLG.

Allergy therapy by intranasal administration with recombinant Lactococcus lactis Producing bovine beta-lactoglobulin.

Background: In the last years, the use of probiotics such as lactic acid bacteria (LAB) has been proposed as an attractive alternative for the management of allergic diseases. A partial prevention from sensitization to bovine beta-lactoglobulin (BLG), one of the major cows' milk allergens, could be achieved in mice after intranasal administration with a recombinant LAB strain, Lactococcus lactis, producing BLG (LL-BLG). This study aimed to evaluate the effects of the LL-BLG strain in a therapeutic protocol.

Sensitization and elicitation of an allergic reaction to wheat gliadins in mice.

We developed a mouse model of allergy to wheat flour gliadins, a protein fraction containing major wheat allergens. We compared the antibody responses (i.e.

Allergic sensitization to bovine beta-lactoglobulin: comparison between germ-free and conventional BALB/c mice.

Background: The 'hygiene hypothesis' suggests that high hygienic standards met in western countries lead to a lack of microbial exposure, thus promoting the development of atopy by preventing the proper maturation of the immune system. Germ-free animals are deprived of the immune stimulation that occurs during postnatal gut colonization by commensal bacteria. Germ-free mice could thereby provide an attractive model for studying the impact of gut microbiota on the development of Th2-mediated disorders such as allergy.

In vivo transfer of plasmid from food-grade transiting lactococci to murine epithelial cells.

We recently demonstrated that noninvasive food-grade Lactococcus lactis (L. lactis) can deliver eukaryotic expression plasmid in mammalian cells in vitro. Here, we evaluated, in vivo, whether a eukaryotic expression plasmid carried by lactococci can translocate to the epithelial cells of the intestinal membrane.

Current prophylactic and therapeutic uses of a recombinant Lactococcus lactis strain secreting biologically active interleukin-12.

The noninvasive and food-grade Gram-positive bacterium Lactococcus lactis is well adapted to deliver medical proteins to the mucosal immune system. In the last decade, the potential of live recombinant lactococci to deliver such proteins to the mucosal immune system has been investigated. This approach offers several advantages over the traditional systemic injection, such as easy administration and the ability to elicit both systemic and mucosal immune responses.

Intranasal coadministration of live lactococci producing interleukin-12 and a major cow's milk allergen inhibits allergic reaction in mice.

The Th1/Th2 balance deregulation toward a Th2 immune response plays a central role in allergy. We previously demonstrated that administration of recombinant Lactococcus lactis strains expressing bovine beta-lactoglobulin (BLG), a major cow's milk allergen, partially prevents mice from sensitization. In the present study, we aimed to improve this preventive effect by coadministration of L.

Allergy to goat and sheep milk without allergy to cow's milk.

Background: Cow's milk (CM) allergy is the most frequent cause of food allergy in infants. Most children who are allergic to CM are also sensitized to whey proteins and/or to the casein fraction and many of them cannot tolerate goat's or sheep's milk (GSM) either. Conversely, the GSM allergies that are not associated with allergic cross-reactivity to CM are rare.

IgE-mediated rat mast cell triggering with tryptic and synthetic peptides of bovine beta-lactoglobulin.

Background: Immunoglobulin E (IgE) epitopes of beta-lactoglubulin (betaLG) have been identified by ELISA inhibition methods using sera from allergic patients. However, the functional capacity of these epitopes to stimulate mast cells is unknown. It is the goal of the present study to identify bivalent IgE epitopes of betaLG able to trigger target mast cells.

Skin localization of cow's milk proteins delivered by a new ready-to-use atopy patch test.

Purpose: Atopy patch tests (APTs) allow the detection of delayed allergies at the skin level. The localization of beta-lactoglobulin delivered into the skin by an innovative ready-to-use APT (E-patch was investigated and the efficacy and safety of this device were assessed.

Methods: The E-patch containing beta-lactoglobulin was placed for 24 h in contact with hairless rat skin mounted in a Franz diffusion cell.

Influence of thermal processing on the allergenicity of peanut proteins.

Peanuts are one of the most common and severe food allergens. Nevertheless, the occurrence of peanut allergy varies between countries and depends on both the exposure and the way peanuts are consumed. Processing is known to influence the allergenicity of peanut proteins.

Oral administration of recombinant Lactococcus lactis expressing bovine beta-lactoglobulin partially prevents mice from sensitization.

Background: The use of probiotics such as Lactococcus lactis and other lactic acid bacteria (LAB) has been proposed for the management of food allergy. However, no experimental study has clearly demonstrated any preventive or therapeutic inhibition of an allergen-specific IgE response.

Objective: We aimed to study the immunomodulatory effect of recombinant L.

Peanut- and cow's milk-specific IgE, Th2 cells and local anaphylactic reaction are induced in Balb/c mice orally sensitized with cholera toxin.

Background: The development of animal models developing specific immunoglobulin (Ig)E presenting the same specificity as human IgE and similar clinical symptoms as those observed in allergic patients are of great interest for the understanding of mechanisms involved in the induction and regulation of food allergy.

Methods: Balb/c female mice were sensitized with whole peanut protein extract (WPPE) by means of intraperitoneal (i.p.