CD8A and neoplasm: Moreover, treatment with the combination of PLX3397 and αPD-1 resulted in a modest (but significant) infiltration of CD8+ T cells compared with vehicle, which induced only a tumor growth delay and not tumor elimination (online supplemental figure S4H), thereby indicating both that elimination of CSF-1R+ MDSC is insufficient to potentiate αPD-1 to induce tumor elimination and that trametinib has a broader effect, such as inducing tumor cell growth arrest.