CD274 and neoplasm: To construct this bispecific fusion protein targeting CD3 on T cells and PD-L1 on tumor cells, single-chain variable fragment (scfv) of anti-CD3 antibody was fused to a high-affinity PD-1 sequence (HAC) published by Maute et al. [13], which was a variant of PD-1 ectodomain strongly binding to PD-L1 (Fig. 1a).