Cytokines concentration in sera (pg/ml) of TR and TS mice measured on days 7, 14 and 21 after the oral infection with 100 and 50 cysts of <i>Toxoplasma gondii</i>.

<p>(A) Concentration of IFN-γ. The TR mice presented about 3 times higher concentrations than TS mice at 7 days of infection. The titers dropped at 14 and 21 day both in TR and TS mice, but TR mice presented higher values on the 21^st day of infection compared with TS mice. (B) Concentration of TNF-α. The titer was higher in the TR mice than in TS mice, especially during the acute stage of toxoplasmosis. Along the course of the disease, concentration of TNF-α in both groups of mice displayed lower titers. (C) Concentration of IL-6. TS mice displayed higher titers of IL-6 during the course of infection compared with the TR mice. Both infected lineages presented higher concentrations, when confronted with non-infected mice. N.I. – non-infected. Bars represent the mean ±SE of three experiments with five mice per group. Statistical differences by the Student <i>t</i> test are indicated by * (p<0.05).