Figure 2.

Treatment efficacy of SFV-IL-12 + anti-CD137 combination on bilateral B16-OVA tumors. (a) C57BL/6 female mice were inoculated in contralateral flanks with 5 × 10⁵ B16-OVA cells on day 0 and then received in the right tumor an injection of saline (top panels), 10⁷ viral particles (vp) (middle panels), or 10⁸ vp of SFV-IL-12 (bottom panels) on day 8. On days 8, 11, and 15 mice received intraperitoneally 100 µg of rat immunoglobulin G (IgG) (left panels) or anti-CD137 mAb (right panels). Red curves represent the evolution of SFV-IL-12-treated tumor diameter and green dotted curves represent the evolution of the nontreated tumor diameter for each individual mouse. Red numbers in the right lower corner of each graph indicate the number of completely rejected treated-tumors and green numbers indicate the number of completely rejected contralateral tumors on day 84 relative to the total number of animals in each group, and the percentage of complete tumor regressions, respectively. (b) Kaplan–Meier plot of mouse survival. The SFV-IL-12 (10⁸ vp) + anti-CD137-treated group was compared with the rest of the groups with the log-rank test. n.s., not significant; *P < 0.05; **P < 0.01;***P < 0.001. The graphs correspond to pooled data from two independent experiments with similar results. α, anti-; SFV-IL-12, Semliki Forest virus encoding interleukin-12.