Fig. 6: mOVA2 immunization delays tumor growth and induces tumor CD8 T cell infiltration.

a Mice were immunized with either mOVA2 or mRIPOδ6 on day 0, boosted on day 14, B16F10.9-OVA cells were implanted subcutaneously 3 weeks later, and tumor volumes were monitored (mice were euthanized when tumors reached 1000 mm³). mOVA2-immunized mice survived significantly longer than mRIPOδ6 treated animals [P = 0.0017, Log-rank (Mantel-Cox) test, n = 10]. A repeat assay including a mock-immunized group is shown in Supplementary Fig. 18. (b) Tumor progression in individual mice from experiment in (a). c B16F10.9-OVA tumors from mOVA2-immunized mice had elevated CD8 T cell infiltration compared to mRIPOδ6-immunized mice. The gating strategy is shown in Supplementary Fig. 17. Two-tailed t-test, n = 4. *P < 0.05, **P < 0.01. d The anti-tumor effect of mOVA2 immunization correlates with SIINFEKL CD8 T cell frequency and is specific to tumors expressing OVA. Mice were immunized with mRIPOδ6, mOVA2, poly(I:C), or poly(I:C) + SIINFEKL as in Fig. 5a, followed by bilateral B16F10.9 and B16F10.9-OVA tumor implantation as shown (left panel). Tumor progression was monitored until reaching >1000 mm³ in the first test animal (asterisks; this occurred in the contralateral B16F10.9 tumors in all treatment groups). mRIPOδ6 n = 9, mOVA2 n = 8, poly(I:C) + SIINFEKL n = 8, poly(I:C) n = 10. All error bars represent SEM; n = number of animals.