To translate the bystander effect and immune function of scFv PD-L1 observed in vitro to anti-tumor activity in vivo, we first sought to evaluate the anti-tumor immune activity mediated by scFv PD-L1 and scFvFc PD-L1 in a CT26 mouse model which is commonly used for testing the efficacy of checkpoint inhibitors with marginal anti-tumor activity when administered as a monotherapy [26, 27]. This evidence concerns the gene CD274 and neoplasm.