Studies on the lymphoid system of mice with lethal acute toxoplasmosis.

Acute toxoplasmosis was induced in CFLP mice by infecting them intraperitoneally with the 25 x 10(3) multiplicity of the virulent RH strain of Toxoplasma gondii. The lymphoid system of mice succumbing to acute toxoplasmosis showed characteristic changes. Significant spleen hypertrophy (spleen index: 1.76), severe thymus atrophy (thymus index: 0.27) and a striking decrease of the lymphocyte count in blood (86%) was found as compared with the uninfected controls.