Figure 5:
PAI vaccine efficacy in a CT-26 tumor model. (A) Study design for tumor challenge model (n=10/group). Mice were implanted with 1.0 × 105 CT-26 cells subcutaneously. They were then treated 13, 18, and 23 d after tumor implantation with the indicated vaccine formulations peritumorally along with checkpoint blockade antibody cocktail (anti-CTLA-4 + anti-PDL-1) intraperitoneally. (B) Kaplan-Maier survival analysis of mice treated with various formulations. (C) Images of representative animals from PBS and PAI/ICB groups on day 33. (D) Tumor growth curves in animals treated with each of the formulations. (E) In a parallel study, mice (n=5/group) were implanted with 2.0 × 105 CT-26 cells on day 0 and treated at 13 d with the indicated vaccine and ICB treatments as in 5A. (F) Blood was collected 2 h post injection for analysis of TNF-α and IL-6. (G-I) Blood cell counts 2 d post-injection: (G) white blood cells (WBCs), (H) Lymphocytes, and (I) Thrombocytes For all experiments, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001. Statistical analyses were performed using one-way ANOVA with Dunnett’s multiple comparisons test in F-I and by using log-rank test with Bonferroni-correction in B.