CONSEQUENCES OF THE INTRODUCTION OF A NEW PROTEIN DURING THE RECOVERY PERIOD OF A CHRONIC INTESTINAL INFLAMMATION

Introduction New foods introduced to an inflamed gut may result in sensitization to this food. AIM Evaluate the time required for recovery to develop tolerance to new proteins after a chronic gut inflammation. Methods: Male C57BL/6 mice(n=30) were immunized with 100μg of peanut protein. Half received a 30-day raw-peanut-challenge-diet (CD) (inflamed-I) while the other received mouse chow (controls-C) (Teixeira 2008). They were further divided and received sweetened OVA (new protein) (20% egg white, 5% sucralose, H₂O,  v/v/v) orally for 7 days, on day 0 (I1/C1), 10 (I2/C2) or 20 (I3/C3) post CD. Body weight, food intake, antibodies and T cell phenotype of mesenteric lymph nodes (MLN) and spleen (SPN) was assessed. ANOVA with Tukey post-test was performed (p<0.05). Approval of local Ethical Committee #00147-09.  Results: OVA consumption was significantly lower in I1 (3.21±1.0) compared to I2 (6.53±1.19), I3 (6.82±2.3) and C (7.5±1.7). The MLN showed a significant increase of CD8⁺T cells of I1 (29.49±4.1) and I2 (31.72±4.0) compared to I3 (21.53±3.6) and C (25.65±5.4) with no significant difference in CD4⁺T cells (I 37.34±5.7 and C 38.35±5.1) and CD4⁺CD25⁺ T cells (I 6.86±1.5 and C 7.00±1.9). Increase of SPN CD4⁺T cells in I1 (38.67±2.5) compared to I2 (25.93±3.48), I3 (24.48±5.9) and C (26.25±12.2) was observed.  The I-1 showed gut inflammation, increased intraepithelial leukocytes, destruction/flatning of the villi and decrease of goblet cells. I-2 and I-3 were similar to C. Conclusions Aversion to novel proteins in the context of gut inflammation may be a protective mechanism to multiple allergies while the recovery period was of at least 10 days.