Abstracts S141
SUNDAY
J ALLERGY CLIN IMMUNOL VOLUME 113, NUMBER 2
461
The Influence of Oral Tolerance on Local and Systemic Immunoregulation in a Murine Model of Type I Allergy
G. N. Drannik1, A. Nakonechna1, H. Renz2, M. Wegmann2, L. M. DuBuske3; 1National Medical University, Kiev, UKRAINE, 2Philipps University Marburg, Marburg, GERMANY, 3Immunology Research Institute of New England, Fitchburg, MA. RATIONALE: Oral tolerance is defined as the induction of a state of systemic immune nonresponsiveness to orally administrated antigen upon subsequent antigen challenge. The influence of high-dose antigen induced oral tolerance on the local and systemic immune response was investigated. METHODS: BALB/c mice were sensitized to OVA. Oral tolerance was induced with OVA using a special feeding regimen before sensitization. Antigen-induced eosinophil infiltration in the lung tissue, and levels of Th1 and Th2 cytokine production in bronchoalveolar lavage fluid (BAL) of sensitized mice was determined. Serum was used for measurement of allergen-specific antibodies. Peripheral blood cell and spleen cell cultures were performed to determine cytokine production before and after in vitro stimulation (IL-2, IL-4, IL-5, IL-10, TNF-alpha and IFN-gamma). RESULTS: Oral administration of OVA in high doses inhibited antigeninduced eosinophil infiltration in the lung in an antigen-specific manner, reducing IL-4 and IL-5 levels and eosinophils in the BAL. In vitro antigeninduced production of IL-2, IL-4, IL-5, IL-10, IFN-gamma was decreased in spleen cells, indicating the induction of both Th1 and Th2 tolerance in vivo. Allergen-specific IgE/IgG1 production was also reduced. CONCLUSIONS: High-doses of antigens provide oral tolerance, influencing both local and systemic immune responses, inducing not only Th1 but also Th2 cell tolerance in vivo and inhibits allergen-induced eosinophil recruitment in lung tissue. Funding: Self-funded