Sera of <i>P. serpens</i>-immunized mice inhibit the activity of TS on platelets.

<p>The mice were injected i.p. with 50 µg of TS in 0.1 ml previously mixed with immune serum A or with normal serum B. A third group of mice received only PBS instead of TS. Platelet counts were determined 24 h later. Values represent the mean ± standard error and are representative of two independent experiments, using 4–7 mice per group. Results were analyzed by analysis of variance (ANOVA) followed by Bonferroni multiple comparisons test. Asterisks indicate significant differences (<i>p</i><0.05) of samples compared with PBS.</p

Mice immunized with <i>P.</i><i>serpens</i> lack antibodies to TS.

<p><i>A</i>. ELISA of plates coated with recombinant TS using control mice serum or sera immunized with <i>P. serpens</i>, followed by infection with <i>T. cruzi. B</i>. Immunoblotting showing the polypeptides recognized by hyperimmune sera anti-<i>P. serpens</i> detected in the whole cellular extract from <i>P. serpens</i>. Alternatively, the TS was also revealed using anti-TS antibody (mAb 39). Number on the left indicate the apparent molecular mass of protein standards expressed in kDa.</p

<i>T.</i><i>cruzi</i> infection induces thrombocytopenia and leukopenia independent of the number of parasites used for infection.

<p>Groups of C5BL/6 mice were infected with 10² or with 10⁵ trypomastigotes (Y strain). <i>A</i>: platelets and <i>B:</i> leukocytes were counts from peripheral blood from uninfected and infected mice. All cell counts were performed 12 days p.i. Values represent the mean ± standard error and are representative of two independent experiments, using 6 mice per group. Comparisons between 2 experimental groups were performed using Student’s <i>t</i>-test. Asterisks indicate significant differences (<i>p</i>≤0.001) when compared with control group (uninfected).</p

Oral exposure to <i>P.</i><i>serpens</i> attenuates thrombocytopenia and leukopenia induced by <i>T. cruzi</i> infection.

<p>C57BL/6 mice received by gavage 2×10⁸ living <i>P. serpens</i> parasites four times at weekly intervals and an i.p. challenge 1 week later with 10⁵ blood trypomastigotes by i.p. route. Whole blood samples were collected on day 12 p.i. <i>A</i>: Platelets counts and <i>B</i>: Leukocytes counts. Values represent the mean ± standard error and are representative of three independent experiments, using 8–12 mice per group. Results were analyzed by analysis of variance (ANOVA) followed by Bonferroni multiple comparisons test. Asterisks indicate significant differences (<i>p<</i>0.001) between infected and uninfected controls. Double asterisks indicate significant differences (<i>p<</i>0.05) between infected mice given PBS (phosphate-buffered saline, pH 7.2) or immunized with <i>P. serpens</i> (PS) prior to infection with <i>T. cruzi</i>.</p

Oral exposure to <i>P.</i><i>serpens</i> decreases parasitemia and mortality in response to <i>T. cruzi</i> infection.

<p>C57BL/6 mice were immunized with <i>P. serpens</i> (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 <i>T. cruzi</i>, <i>A</i>: 10², <i>B</i>: 5×10³ and <i>C</i>: 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 (<i>p</i><0.05). (≠) indicates that all animals died.</p

<i>T.</i><i>cruzi</i> infection induces thrombocytopenia and leukopenia transients in the early of infection.

<p>C5BL/6 mice were infected with 5×10³ trypomastigotes (Y strain) via i.p. injection, monitored for the development of thrombocytopenia and leukopenia, and sacrificed at different time points post-<i>T. cruzi</i> infection. <i>A</i>: platelets and <i>B</i>: leukocytes were counts from peripheral blood from uninfected and infected mice. Values represent the mean ± standard error and are representative of three independent experiments, using 4–15 mice per group. Results were analyzed by analysis of variance (ANOVA) followed by Bonferroni multiple comparisons test. Asterisks indicates significant differences (<i>p<</i>0.05) when compared with control group (uninfected).</p

TS reduces blood platelets counts in naïve C57BL/6 mice.

<p>Mice were inoculated i.p with 50 µg of recombinant TS. <i>A</i>: platelet, <i>B</i>: leukocyte and <i>C</i>: megakariocyte counts were determined 24 h later. Values represent the mean ± standard error and are representative of two independent experiments; using 7–15 mice per group Results were analyzed by analysis of variance (ANOVA) followed by Bonferroni multiple comparisons test. Asterisks indicate significant differences (<i>p</i><0.05).</p