Prior Food-Induced Allergic Gut Inflammation Leading To Multiple Food
Allergies in C57Bl/6 Mice
Abstract
BACKGROUND: Food allergies are usually managed by food avoidance. Hidden
allergens in food, due to cross-contamination and/or allergenic
additives added during production, place an important concern in today’s
increasing food allergy cases worldwide. Previous studies showed that
introduction of new food components, in an inflamed intestine, results
in sensitization to this food. Thus, our aim was to evaluate the
kinetics of multiple food allergy induction. METHODS: Adult male C57BL/6
mice were divided into five groups, four of which were submitted to an
intestinal inflammation induction protocol to peanuts. Egg white (OVA)
diluted 1:5 v/v in distilled water was instilled by gavage 6h-before
(EXP-1), concomitant (EXP-2) and 6h-after (EXP-3) the onset of the
peanut challenge diet. Positive control (POS CONT) and NEG CONT received
saline per gavage. Finally, animals were challenged with subcutaneous
injections of OVA. RESULTS: No changes in diet intake were observed.
Anti-OVA total IgG antibody titers significantly increased in EXP-2.
Flow cytometry revealed significant decrease in CD4+CD25+Foxp3+ and
significant increase in TCD8+ in EXP-2. Histomorphometrically, EXP-2 and
EXP-3 were classified as Infiltrative and Partial Destruction stages.
EXP-1 was classified as Infiltrative, while POS CONT was classified as
Partial Destruction. NEG CONT was classified as Normal. CONCLUSION: The
introduction of a new food only a few hours before the initiation of a
gut inflammation is able to induce oral tolerance, however the
introduction of a new dietary protein concomitant to the onset or during
an ongoing gut inflammation may induce multiple allergies.