Figure 7.

Tissue inflammation and parasite burden in vaccinated mice post-challenge infection. Mice were vaccinated as in Figure 1, challenged with T. cruzi at 21 days' post-vaccination and euthanized at 21 days post-infection. (A–J) Paraffin-embedded left ventricular heart (A–E) and skeletal muscle (F–J) tissue sections (5 μM) were examined by hematoxylin/eosin staining (blue: nuclear; pink: muscle/cytoplasm). Shown are representative H&E images of tissue sections from vaccinated/infected and non-vaccinated/infected mice. Non-treated/non-infected mice were used as controls. (K,L) Total DNA was isolated from heart (K) and skeletal muscle (L) tissue sections and submitted to real-time qPCR amplification of Tc18SrDNA sequence (normalized to murine GAPDH). Data (mean ± SD) are representative of two independent experiments (n = 4 mice per group per experiment, triplicate observations per sample). Significance is annotated as *none vs. vaccinated or infected vs vaccinated/infected, and ^∧comparison of vaccinated groups (*,^∧p < 0.05, **,^∧∧p < 0.01, and ***,^∧∧∧p < 0.001).