Figure 3
CATH-1 protects mice against SS2 infection. Mice (n = 30, each group n = 10) were intraperitoneally infected with SS2 strain SC19 (2.5 × 108 CFU) and PBS and then intraperitoneally treated with CATH-1 at 2 h post-infection. Mice survival (%) was monitored for 7 days (A). After 8 h infection, different samples (n = 15, each group n = 5) including liver, lung, spleen, blood, and peritoneal lavages were collected and bacterial load was quantified by colony counting assay (B). Meanwhile, histopathological changes in liver, lung, and spleen were observed by H&E staining (C). In addition, peritoneal lavage was collected at 8 h infection to determine cytokine production including IL-1β, IL-1α, IL-6, IL-12, IL-18, and TNF-α (D). Data are represented as means ± SEM of one independent experiment of five mice. *p ≤ 0.05, **p ≤ 0.01, ns, no significance.