FIG. 3.

Trypomastigote-induced parasitemia and mortality in mice immunized with pcDNA3-TS, p154/13, and pcDNA3. BALB/c mice were immunized with pcDNA3-TS, p154/13, or pcDNA3. Three weeks after the last immunization, mice were challenged i.p. with 6,500 bloodstream trypomastigotes. (A) Course of parasitemia, estimated as described in Materials and Methods. The results represent the mean values obtained from eight mice ± the standard deviations. At the peak of infection (day 7), the parasitemia of mice immunized with pcDNA3-TS or p154/13 was significantly lower than the parasitemia of control animals injected with pcDNA3 (p<0.001). (B) Kaplan-Meier curves for survival of eight mice immunized with the indicated plasmid(s). Statistically significant survival was observed in mice immunized with pcDNA3-TS or p154/13 compared to animals that received pcDNA3 (P < 0.05).