Anti-acid medication during pregnancy promotes the induction of food allergy in newborn mice

Food allergies are steadily increasing and to date affect about 2% of adults and 6-8% of children younger than 3 years. Today, neither the reasons for this increase nor the underlying induction mechanisms are fully understood. We have shown in previous studies that the intake of anti-acid drugs can hinder gastric digestion and thereby inhibits food protein degradation. In consequence, the preserved structure of the allergen can promote IgE- induction and allergic responses. We could recently prove this hypothesis in mice using fish and hazelnut proteins for feedings under hypoacidic conditions. More importantly, in an epidemiological study of human gastroenterological patients increased food-specific IgE and skin reactivity after treatment with acid-suppressing drugs were observed, indication that this mechanism accounts also for humans. These medications find broad application not only in adult patients, but also in pregnant women and in newborns and preterm babies. Consequently, we intend in the present project to investigate the effects of anti-acid drugs on the immune response to dietary proteins in a murine model. Codfish proteins will be fed alone or in context with anti-ulcer medications to the dams during pregnancy or during the lactation period. We expect that peptic digestion is hindered in the anti- acid treated groups and, consecutively, the whole codfish protein to be transferred via the placenta and/or via the breast milk to the suckling offspring. Resulting food sensitization (Th2-response) will be monitored in serum samples (antibodies, cytokines), skin test reactivity, oral provocations, splenocyte proliferation and cytokines in their supernatants, and counts of eosinophils and mast cells in tissue samples of stomach and intestine. We expect that our study will shed light on the question whether the generous application of anti-ulcer drugs contributes to the increasing number of allergic diseases in young infants.