Abstract: | Using the Wistar rat as experimental animal for Schistosoma mansoni infections it was shown that reaginic antibody response to S. mansoni antigens depends on the infection dose in a way that low infection doses induce persistent titres whereas high doses provoke transient titres. Repeated infections strongly favoured the reagins. In contrast, total serum IgE levels measured by ELISA followed a rather constant time course, independent from the mode of infection. Antigen-specific IgE antibodies followed none of the time courses and reached maximum levels about 12-15 weeks post infectionem. The data allow to suppose that different types of IgE occurred possessing different capacities to sensitize mast cells. |