This work reports results of re-infection of BALB/c and C57BL/6 mice with different recombinant strains of Toxoplasma gondii. Mice were prime-infected with the non-virulent D8 strain and challenged with virulent strains. PCR–RFLP of cS10-A6 genetic marker of T. gondii demonstrated that BALB/c mice were reinfected with the EGS strain, while C57BL/6 mice were re-infected with the EGS and CH3 strains. Levels of IF...