Figure 4. Oral exposure to P. serpens decreases parasitemia and mortality in response to T. cruzi infection.

C57BL/6 mice were immunized with P. serpens (2×10⁸ living parasites per 0.1 mL PBS administered by gavage) four times with one-week intervals. Seven days after the last immunization mice were infected with Y strain of T. cruzi, A: 10², B: 5×10³ and C: 10⁵ trypomastigote forms, respectively. Parasitemia were assessed over 30 days post infection. D: Survival of immunized mice and infected with 10⁵ (lethal dose). Data are represented as mean ± standard error represented of at last 10 mice per group. Asterisks indicates significant differences (p<0.05). (≠) indicates that all animals died.