Fig. 5

A workflow was established for screening PD-1/PD-L1 inhibitors. a SPR technology was performed to evaluate binding affinities followed by PD-1/PD-L1 pair ELISA assay. Once the inhibitors exert blockage effects on PD-1/PD-L1 interactions, bioluminescence reporter cell-based assay will be applied for determining their biological functions. b The binding and inhibitory effects of Punicalagin (PA) and BMS1166 against human PD-L1 protein assessed using SPR and PD-1/PD-L1 pair ELISA assays, respectively. PA or BMS1166 was allowed to flow over Fc-PD-L1 captured on a flow cell as well as on a reference cell of Series S Sensor Chip