Fig. 8
Histological analysis of mice challenged intraperitoneally with T. pyogenes TP7 and T. pyogenes TP8. The mice were intraperitoneally challenged at day 43 with 3.7 × 108 CFU T. pyogenes TP7 (A1-G1) or T. pyogenes TP8 (A2–G2), respectively. The livers of seven groups of immunized mice were collected for evaluation of histology alteration. PBS was used as a control