Genetic Vaccination against Experimental Infection with Myotropic Parasite Strains of Trypanosoma cruzi
Figure 1
Frequencies of specific cytokine-secreting splenic CD8+ T cells in mice vaccinated with the heterologous prime-boost vaccination regimen. F1 (CB10XBALB/c) mice were immunized i.m. in each tibialis anterior muscle with plasmid DNA. For priming, G1 received control plasmid pcDNA3 (300 μg), G2 was immunized with a mixture of pIgSPCl9 and p154/13 (200 μg), and G3 received a mixture of pIL-12, pIgSPCl9, and p154/13 (300 μg). Twenty-one days later, these mice received, in these same spots, 100 μL of a viral suspension containing a total of 2 × 108 pfu of rec. adenovirus. For boosting, G1 received control adenovirus Adβgal, and G2 and G3 were immunized with a mixture of rec. adenovirus AdASP-2 and Ad-TS. Immunological assays were performed 14 days after viral inoculation. Spleen cells were restimulated in vitro in the presence or absence of the peptides VNHRFTLV or IYNVGQSVI, anti-CD107a, anti-CD28, BdGolgiPlug, and monensin. After 12 h, the cells were stained with anti-CD8, anti-IFNγ, and anti-TNF. (a) The histograms show FACS analysis of CD8+ cells. The numbers represent the frequencies of cells stained for CD107a and/or IFNγ. The results are a representative of 4 mice per group (Median). (b) Frequencies of CD8+ cells stained for IFNγ and/or TNF. The results are a representative of 4 mice per group (Median). (c) Total frequencies of CD8+ cells specific for the peptide VNHRFTLV and stained for CD107a or IFNγ or TNF. The results are representative of 4 mice per group (Mean ± SD). (d) Frequencies of CD8+ cells specific for the peptide VNHRFTLV and stained for each marker (CD107a, IFNγ, or TNF). The results are representative of 4 mice per group (Mean ± SD). (e) Same as in (c) for CD8+ cells specific for the peptide IYNVGQSVI. The results are representative of 4 mice per group (Mean ± SD). (f) Same as in (d) for CD8+ cells specific for the peptide IYNVGQSVI. All three groups were compared statistically by one-way ANOVA followed by Tukey HSD (c–e). The values of G2 and G3 mice were always higher than those of G1 mice ( in all cases). Asterisks denote that the values of G3 mice were higher than those of G2 mice (). The results are representative of three independent experiments.
