PARTICULATE ASPERGILLUS-FUMIGATUS ANTIGENS ELICIT A T-H2 RESPONSE IN BALB C MICE/

Background: In order to understand the immunoregulation in allergic as pergillosis, a murine model was developed by exposing animals to parti culate and soluble antigens of Aspergillus fumigatus. Methods: BALB/c mice were exposed to soluble Aspergillus antigen intranasally. Animals showing moderate levels of IgE were subsequently exposed to soluble a ntigen or antigen conjugated to polystyrene beads intranasally. The Ig E and IgG(1) in the sera and the eosinophils in the blood and lungs we re studied. The spleen and lung mononuclear cells were stimulated with both concanavalin A and antigen 2 and evaluated for production of int erleukin (IL)-4, IL-5, IL-10, and interferon-gamma. Results: Animals e xposed to particulate antigens shelved more elevated serum IgE levels and increased members of eosinophils in the blood and lungs than those exposed to soluble antigen. Lung cell cultures from animals exposed t o particulate antigens when stimulated with Aspergillus produced IL-4 and IL-5, indicating a T-H2 type of response. Animals exposed to solub le antigens showed a weaker T-H2 response, as evidenced by low IgE lev els in sera, fewer eosinophils in the blood and low levels of cytokine production from lung and spleen cells. Conclusion: The results indica te that the physical nature of the antigen may have a major role in de termining the type of immune response of the host.