Evaluation of T. cruzi infection by ex vivo and in vivo bioluminescent imaging of chronic infection. For ex vivo evaluation of organs, images were acquired after incubation with D-luciferin in PBS in a plate, the settings were 5 minutes exposure and binning medium (pixels size). For in vivo evaluation, bioluminescent images were acquired in ventral (left panel), dorsal (central panel), and lateral (left panel) position after 10 minutes of intra-peritoneal inoculation of D-luciferin. The settings were binning small (small pixels), 1 minute exposure. 14 dpi (A), 21 dpi (B), 28 dpi (C), 180 dpi ex vivo (D), 180 dpi in vivo (E) and negative control (F). 1–heart, 2–rectum, 3–snout, 4–testicle and adipocyte, 5–forepaw, 6–hindpaw, 7–tail, 8–ear, 9–small intestine, 10–large intestine. For bioluminescent signal quantification, subject ROI (square) identified the animal in the image of ventral position, average background ROI was placed in the animal or in the plate, on the liver, (Bkg, circle in red dots) to measure the background bioluminescent signal which was used to correct the signal in an automatic measurement ROI (red line, circle), to produce a background-corrected bioluminescent signal. Scale bar of bioluminescent image radiance (photons/ sec/ cm2/sr).