To get mechanistic insights into the role of Treg-derived CD27 with combinatorial PD-1 signaling blockade on CD8+ T cell mediated antitumor immunity, we analyzed numbers and effector functions of tumor infiltrating CD8+ T cells in MC38-bearing FoxP3.Luci-DTR5 + CD27 − / − mixed chimeric mice. This evidence concerns the gene CD8A and neoplasm.