Maternal dietary antigens and the immune response in the offspring of the guinea-pig.

Guinea-pig dams and their litters were raised on either a cow's milk protein-containing diet (MCD) or a milk-free diet (MFD). At 8 weeks of age all litters were challenged i.p. with 50 micrograms milk whey-protein concentrate (V67) and 100 mg A1(OH)3 in saline. The immune response was estimated 2 weeks later as the serum IgG antibody titres against V67, beta-lactoglobulin (beta-LG) and alpha-lactalbumin (alpha-LA) using enzyme-linked immunosorbent assay (ELISA) and the tracheal Schulze-Dale response to these antigens. Feeding milk protein antigen to dams from birth and during pregnancy induces antigen-specific hyporesponsiveness (tolerance) in their offspring, despite no direct contact between the offspring and the milk proteins. Tolerance seems to be induced by the antigen itself since withdrawal of the MCD 10 days before delivery reduced tolerance in the offspring. No tolerance was produced in the offspring of dams fed the antigen from 3 months of age (adult). beta-LG appears to be a major antigen in milk whey while alpha-LA is a minor one since there was almost no antibody or tracheal response to alpha-LA in any of the animals tested. The results indicate that maternal antigen experience and antigens present during pregnancy are important for the subsequent immune response to these antigens in offspring

Prevalence of food hypersensitivity in relation to IgE sensitisation to common food allergens among the general adult population in West Sweden

Abstract Background The prevalence of self-experienced adverse reactions to foods seems to have an increasing trend in both adults and children. However, it is unclear if the prevalence of food hypersensitivity in the Swedish adult population is still rising, what symptoms are caused by different foods and which are the most common foods to which adults are more frequently IgE-sensitised. Methods In a cross-sectional study based on questionnaire responses, interviews and clinical examinations as part of the West Sweden Asthma Study, 1042 subjects from the general population, 17–78 years of age, living in Västra Götaland, Sweden, were included. The subjects reported symptoms for 56 specified foods and blood samples were taken to examine the IgE-sensitisation pattern for 9 common foods. Results Approximately 32% of adults reported food hypersensitivity, affecting mostly women and subjects less than 61 years old. The foods most often reported to cause adverse reactions were hazelnut (8.9%), apple (8.4%), milk (7.4%) and kiwi (7.3%). Less than one percent (0.9%) reported symptoms from ingestion of meat. Symptoms mostly affected the gastrointestinal tract (15%) and the skin (2.7%). Sixteen per cent were IgE-sensitised to common foods, most often to hazelnut (13.3%), peanut (4.9%) and almond (3.0%), while 5.9% reported symptoms and were IgE-sensitised to the same food, mainly to hazelnut (5.3%). Conclusions The prevalence of self-reported food hypersensitivity in West Sweden indicates a rising trend. The correspondence between self-reported symptoms and IgE-sensitisation to foods is generally poor, except for hazelnut and almond which exhibit moderate or fair correlation

Switched CD21–/low B cells with an antigen-presenting phenotype in the infant thymus

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Different expression of IL-2 receptor α-chain on a lamina propria T cell population and goblet cells in rats orally tolerized or sensitized to ovalbumin (OA) after colonization with an OA-producing Escherichia coli

The aim of this study was to compare the local gut immune response in sensitized and orally tolerized experimental animals. The development of IgE/IgG antibodies and the DTH to OA was studied in rats made orally tolerant to OA and compared with sensitized control rats after colonization with an Escherichia coli genetically engineered to produce OA. At 3 weeks of age, pups were weaned onto a standard diet without OA or an OA-containing diet for 4 weeks and then switched to a standard diet without OA. Both groups of rats were parenterally immunized with a mixture of OA and human serum albumin (HSA) in Freund's complete adjuvant when they were 8 weeks old. After DTH measurement 2 weeks later, all rats were colonized with an E. coli producing OA for 5 days. The local immune response in the small intestine was assessed, using immunohistochemistry, as the expression of MHC class II molecules and IL-2 receptor (IL-2R) α-chain. The OA-tolerant rats showed the classical signs of oral tolerance, with a reduced IgE and IgG antibody and DTH response to OA before colonization. The difference between the two groups in the anti-OA antibody response became even more pronounced after colonization with the E. coli that produce OA. Rats orally tolerant to OA maintained a normal villus architecture after colonization, with a normal expression of MHC class II molecules similar to non-treated adult rats, but with a significantly higher (P = 0.004) expression of IL-2R α-chain on T cells in the lamina propria of the villus core compared with sensitized control rats. The tolerant rats showed a very weak staining with the anti-IL-2R α-chain-specific antibody on a few goblet cells in only one out of seven rats. In the sensitized control rats, a marked local immune response was seen with an intense staining with a monoclonal anti-IL-2R α-chain-specific antibody on goblet cells in five out of seven rats (P = 0.019) and also an increased expression of MHC class II molecules in the epithelial cells and cells in the lamina propria of all rats. Rats orally tolerant to OA maintained a normal villus architecture after colonization, but with a significantly higher (P = 0.004) expression of IL-2R α-chain on T cells in the lamina propria of the villus core compared with sensitized control rats. The novel finding that goblet cells express IL-2R α-chain and the striking difference in expression of the receptor and the numbers of goblet cells between tolerant and sensitized rats may suggest a direct T cell regulation of the goblet cells. A possibility that oral tolerance might be maintained by the activated T cells expressing IL-2R α-chain in the lamina propria of the villus core is also discussed