The effect of chemo-immunotherapy with SDDS, pyrimethamine and anti-toxoplasma serum on toxoplasma gondii cysts in latent infected NMRI mice.

A substantial reduction of brain cyst numbers could be obtained through a six week therapy with SDDS-pyrimethamine combination or a high titer anti-Toxoplasma serum. NMRI mice experimentally infected three months earlier with cyst-forming Toxoplasma strains Witting, Alt or Gail were used. The effectiveness of the treatments could be increased considerably by simultaneous administration of anti-Toxoplasma serum and SDDS-pyrimethamine. A highly significant reduction of brain cyst numbers, upto 65%, could be obtained by using this mode of chemoimmunotherapy. The effectiveness of the treatments used varied amongst the three Toxoplasma strains.