Figure 4.

Immune response elicited by the therapeutic vaccine at 120 dpi, in mice treated during the acute phase of T. cruzi infection. Mice infected with a sublethal dose of T. cruzi were treated with three doses of Salmonella at 0, 10, and 20 dpi (n = 5 per group), and the immune response generated was analyzed at 120 dpi. The IgG titers (A) anti-rChg, (B) anti-rCz, and (C) anti-F105 were measured in sera at 120 dpi. Cellular response: The in vivo DTH assay was performed by measuring the plantar footpad before and 48 h after intradermal inoculation of (D) rChg or (E) rCz; results are expressed as the differences in thickness. Splenocytes from mice sacrificed at 120 dpi were restimulated with 10 μg/ml (F) rCz, (G) rChg, or (H) F105 for 5 days, and thymidine uptake was determined. The results are expressed as the differences between the cpm of stimulated and baseline cells. (I) Intracellular production of INF-γ, determined by flow cytometry, after the stimulation of the splenocytes with the different antigens. These results are representative of at least three independent experiments. *p < 0.05, **p < 0.01.