Soy- and shrimp-specific IgE responses in orally and intraperitoneally immunized mice.

Female C3H/HeJ mice were immunized parenterally and/or intragastrically with two important food allergens, soy and shrimp. Although both preparations elicited specific IgE production when administered intraperitoneally, anti-shrimp titers were consistently higher. Soy or shrimp administration, i.g. with Pertussis adjuvant (intraperitoneally or intragastrically) did not induce detectable reaginic antibody. Animals treated with soy intragastrically were unable to produce a soy-specific IgE response upon intraperitoneal immunization. The combination of soy and Pertussis (intragastric) did, however, abrogate this tolerizing effect on IgE synthesis. In contrast to soy, the shrimp antigens (intragastric) did not act as tolerogens and were found to enhance subsequent reaginic responses produced by intraperitoneal immunization. These results are considered with respect to mechanisms operative in food allergy.