PDCD1 and neoplasm: One hypothesis is that sensing of CBM588 may promote resistance to apoptosis of tumor-specific CD8+ T cells to a similar extent as what observed when mice with advanced tumors receive Cetuximab-based IL-10 fusion protein.29 In agreement with this possibility, qRT-PCR analysis revealed a similar gene expression profile with the tumor of mice that were treated or not with CBM588 upon PD-1 blockade (Supplementary Figure S9).