Splenic T cell functional profile in TcVac3-immunized mice infected with T. cruzi.

Mice were immunized with empty vector or TcVac3 (± cytokine adjuvants), and infected with T. cruzi, as detailed in Materials and Methods. Splenocytes were obtained 2-weeks after vaccination or at day 30 (acute) and 120 (chronic) post-infection, and in vitro stimulated for 48 h with TcG2 and TcG4 recombinant antigens or T. cruzi lysate (TcTL). The cell free supernatants were used to measure IFN-γ, TNF-α, IL-4, and IL-10 levels by an ELISA (A). Cells were labeled with appropriate fluorescent-tagged antibodies, and flow cytometry was performed to gate for proliferating (Ki67+) and non-proliferating (Ki67-) CD8+ T cells producing cytokines (B). Data (mean ± SD) are representative of three independent experiments (n = 4/group). ND = Not detectable. Statistical analysis was done using ANOVA with post hoc Tukey’s test. The level of significance between control versus vaccinated (TcVac3 or TcVac3+cytokine adjuvants) is shown by *and between TcVac3 versus TcVac3+cytokine adjuvants by # (*,#p,##p,###p