rAdVax immunotherapy recovered the injured heart tissue of chronically <i>T. cruzi</i>-infected mice.

<p>(<b>A</b>) Chronically Colombian <i>T. cruzi</i> strain-infected mice were evaluated for heart injury markers pre-therapy (120 dpi) or primed-boosted with 2 × 10⁸ plaque-forming units (PFU) of rAdCtrl or a mixture of 10⁸ PFU of each adenovirus vaccine preparation (rAdASP2+rAdTS; rAdVax). Mortality was recorded until 230 dpi (110 days post-therapy; dpt), when the surviving mice were analyzed for heart injury markers. (<b>B</b>) Kaplan-Meier curve representing the percentages of surviving mice (14–20 mice/group in two independent experiments). (<b>C</b>) Relative spleen weight (mg of spleen/g of body) and quantitative immunohistochemical staining (IHS) data for <i>T. cruzi</i> parasitism (nests/100 microscopic fields) in the heart tissue of chronically infected mice (120 and 230 dpi, respectively, pre- and post-therapy). (<b>D</b>) IHS showing fibronectin (FN)-stained areas in representative cardiac tissue sections of noninfected (NI) controls and chronically <i>T. cruzi</i>-infected mice pre- (120 dpi) and post-therapy (230 dpi; 110 dpt) with rAdVax. (<b>E</b>) Quantification of the FN-stained area (%) and connexin 43 (Cx43)-containing gap junction distances detected using IHS staining of heart tissue sections of NI controls or <i>T. cruzi</i>-infected mice pre- and post-therapy with rAdVax. (<b>F</b>) Evaluation of CK-MB activity in the serum of NI controls and <i>T. cruzi</i>-infected mice pre- and post-therapy with rAdVax. The data are presented as the means ± SD. ** <i>P</i> <0.01 and ***<i>P</i> <0.001, experimental groups compared with NI controls. ^#<i>P</i> <0.05 and ^##<i>P</i> <0.01, rAdVax-immunized compared with pre-therapy <i>T. cruzi</i>-infected mice.