Tissue parasitism and histological changes of infected BALB/c and C57BL/6 mice. Both mice lineages were orally infected with 5 T. gondii cysts and treated with ZnPPIX (10 mg/kg/day), hemin (5 mg/kg/day) or vehicle (Na2CO3 + NaCl). The tissue parasitism in the lung (a), small intestine (b), liver (c) and brain (d) was detected by immunohistochemestry staining and scored by counting the number of parasitophorous vacuoles and cyst-like-structures per 50 microscopic fields in the lung and the small intestine or per tissue section in the liver and in the brain. Representative photomicrographs of histological changes of BALB/c and C57BL/6 mice (e,f) and inflammatory score in the lung (g) assessed by H&E staining. Representative photomicrographs of histological changes of BALB/c and C57BL/6 mice (h,i) and inflammatory score in the small intestine (j). Data are representative of at least two independent experiments of five mice per group that provided similar results. *Statistically significant differences between experimental conditions in the same lineage of mice (ANOVA and Bonferroni multiple comparison post-test, P < 0.05). #Statistically significant differences between the two mouse lineages submitted to the same treatment conditions (Student’s t test, P < 0.05).