Figure 7. Survival of B16F10 and MC38 tumor-bearing mice. Mice bearing a B16F10 tumor or MC38 tumor were treated starting 15 days or 8 days after inoculation, respectively, when the tumors were ~60 mm³. The dual-LNPs were injected intratumorally (IT) weekly for a total of 4 weeks at a dose containing 4 µg of CPG and 10 µg of VISTA siRNA. Mice were IT injected with VISTA-siRNA-only LNPs at a dose of a 10 µg siRNA 3 days following every dual-LNP treatment. Similar schedule and dose were used for the control treatments. (A) B16F10 tumor growth curves for groups treated with dual-LNP, control LNP (VISTA siRNA+non-stimulatory GPC), control LNP (CPG+non-targeting siRNA), VISTA mAb and soluble CPG, or PBS (n=4–5 per group). (B) Kaplan-Meier survival of B16F10 tumor-bearing mice. (C) B16F10 tumor growth curves following tumor rechallenge of the complete responders treated with dual-LNP. The rechallenge experiment was conducted with the three complete responders and four naïve control mice. (D) MC38 tumor growth curves for groups treated with dual-LNP or PBS (n=6 for the dual LNP-treated group; n=5 for the PBS control group). (E) Kaplan-Meier survival of MC38 tumor-bearing mice. (F) MC38 tumor growth curves following tumor rechallenge of the complete responders treated with dual-LNP. The rechallenge experiment was conducted with five complete responders and four naïve control mice. LNP, lipid nanoparticle; VISTA, V-domain immunoglobulin suppressor of T cell activation; PBS, phosphate-buffered saline.