Protection of C3H/HeN mice against Toxoplasma infection. Eight- to ten-week-old mice (8/group) were immunized on days 0, 14, 28 and 42 by subcutaneous injection. Two weeks after the last boost, mice were challenged by gavages with 20 cysts of the Me49 strain (LD50). Thirty days after the challenge, the number of brain cysts in mice was determined. Each bar represents the group mean ± S.E.M.a = p < 0.05: SAG vs. Control and naïve, and SAG1+Boost vs. Control+Boost; b = p < 0.01: SAG1+Boost vs. Control and SAG1+Boost vs. naïve. Control: mice vaccinated with pzp200-infiltrated leaf extracts, SAG1: pKnS-infiltrated leaf extracts, Control+Boost: pzp200-infiltrated leaf extracts + rSAG1 prime boost, SAG1+Boost: mice vaccine with pKnS-infiltrated leaf extracts plus rSAG1 prime boost. The results represent one of two similar experiments. Statistical analysis was performed by one-way analysis of variance (ANOVA) using the Bonferroni's Multiple Comparison Test.