Effect of TLR agonists on the frequency of tumor infiltrating MDSC, NK and CD8 T cells. Mice were treated as described in Figure 1. The frequency of tumor-infiltrating MDSC, NK and CD8+ T cells was determined one day after the second treatment. Results show the mean + SD of each cell type as a percentage of total CD45+ tumor infiltrating cells analyzed independently in 6 mice from 2 independent experiments. *, p < 0.05; **, p <0.01.