Immune response after immunization with an experimental Toxoplasma gondii ISCOM vaccine

Mice were immunized with ISCOM preparations of tachyzoites from two different strains of Toxoplasma gondii. The antibody response and the cellular response, as measured in vitro, were comparable with those found in chronically infected mice. When challenged with virulent T. gondii tachyzoites, all the immunized mice died, whereas all the chronically infected mice survived. However, the immunized mice generally survived longer than non-immunized animals.