Figure 3.

Disease phenotypes induced by various mutant viruses. (a) Experimental design. A/J mice were infected with wt CVB3, pBRCVB3, Mt 2, Mt 3, Mt 4, Mt 8, and Mt 10 viruses, with saline recipients as controls. At termination on day 21, heart and pancreas were collected for histology. (b) Clinical phenotypes. Body weights were taken every one to two days until termination and compared between groups (left panel); mortalities, if any, were noted to calculate survival rates (right panel). (c) Histopathology. Hearts and pancreata collected at termination on day 21 were processed for standard histology to evaluate inflammatory changes. Representative sections of hearts (top panel) and pancreata (bottom panel) from saline (negative control), wt CVB3 and pBRCVB3 (positive controls), and Mt 10 virus groups are shown. Solid and empty arrows represent infiltrations of MNCs in the heart and pancreatic sections, respectively. Circles indicate necrotic areas in the pancreatic sections. Magnification, 20×; scale bars, 20 µm. Data sets obtained from two individual experiments, each involving n = 4 to 5 mice, are shown. Two-way ANOVA with a Sidak’s post-test was used to compare body weight changes in saline group relative to wt CVB3/pBRCVB3 groups. Log-rank test with Bonferroni correction was used to compare survival curves. ****p ≤ 0.0001.