CD80 and neoplasm: DCs and macrophages in tumor-draining lymph nodes was used to investigate whether the blockade of PD-L1 could enhance the activation of APCs in mice vaccinated with PEK protein vaccine are shown in Figure 4A. The percentages of CD80+ CD11c+ DCs (2.89 ± 0.05%) was significantly higher among mice treated with the PEK protein vaccine plus anti-PD-L1 Ab than among those treated with the PEK protein vaccine alone (2.11 ± 0.05%, p < 0.001, Student’s t-test; Figure 4B).