(A) Survival curves of C57BL/6 mice after challenge with Neospora caninum . Four mouse groups (13 animals per group) were immunized with either Neospora lysate antigen (NLA) associated with Synadenium carinatum latex lectin (ScLL), or NLA alone (antigen control), or ScLL alone (lectin control), or PBS (infection control). Mice (10 animals per group) were challenged with 2x107 tachyzoites of the Nc-1 isolate at 60 days after immunization. *P < 0.05 (Log-rank test). (B) Parasite burden in the brain tissue from all surviving mice after 30 days of challenge and analyzed by real-time PCR. Bars represent median with interquartile range. *P < 0.05; **P < 0.01; ***P < 0.001 (Kruskal-Wallis test and Dunn multiple comparison post-test). (C) Representative photomicrographs of immunohistochemical assays in the brain tissues from mice of the four groups: NLA + ScLL, NLA, ScLL, and PBS. Arrows indicate strongly stained free tachyzoites and parasitophorous vacuoles from N. caninum in NLA and PBS panels (original magnification,×100); NLA + ScLL and ScLL panels (original magnification, × 40).