Figure 2. Cytotoxicity and activity of BMS compounds in PD-1/PD-L1 checkpoint assay.

(A) Cytotoxicity of BMS compounds against the PD-1 Effector Cells was tested using metabolic activity assay following the 48 h treatment of the cells with the indicated compounds. The presented EC₅₀ values (right panel) are means ± SEM from the three independent experiments (left panel shows a representative result). (B, C) Activities of reference antibodies (B) and BMS compounds (C) in alleviating the effect of PD1/PD-L1 checkpoint on TCR-mediated T cell activation are expressed as the level of luciferase activity (for details see Materials and Methods). The graphs present relative luminescence normalized to the DMSO-treated controls and are representative of the three independent experiments. (D) The result of the fitting of Hill model to experimental data presented on panels B and C. EC₅₀ values represent half maximal effective concentrations, and RLU_max values represent maximal relative luminescence values, and illustrate the potency of the listed molecules in restoring the activity of ECs in the assay.