PDCD1 and neoplasm: When these three almost cured mice in the R848@M2pep-MPsAFP and anti-PD-1 antibody-treated group were re-challenged with Hepa1-6 cells in left flank and B16-OVA cells in right flank, lower tumor volume (Supplementary Fig. 33g) of Hepa1-6 tumors, but not B16-OVA tumors (Supplementary Fig. 33h) were detected compared with naïve mice, confirming that combined treatment of R848@M2pep-MPsAFP and anti-PD-1 antibody generated strong antigen-specific immunological memory.