CHEMBL5736657

In Vitro Activity Assay: In vitro activity evaluation: Cisbio PD-1/PD-L1 binding assay kit was applied for the detection method of in vitro enzymology level.Screening Principles and Methods of PD-1/PD-L1 Small Molecule Inhibitors1) Principle: PD-1 protein is with HIS tag, and PD-1 ligand PD-L1 is with hFc tag. Eu labeled anti-hFc antibody and XL665 labeled anti-HIS antibody are combined with the above two label proteins respectively. After laser excitation, energy can be transferred from donor Eu to receptor XL665, allowing XL665 to glow. After adding inhibitors (compounds or antibodies), blocking the binding of PD-1 and PD-L1 makes the distance between Eu and XL665 far away, the energy can not be transferred, and XL665 does not glow.2) Experimental method: The specific method can be referred to Cisbio's PD-1/PD-L1 Kit (item 64CUS000C-2). Reagents should be dispensed in the following order. For 384-well white ELISA plate, 2 μl of diluent or target compound diluted with diluent was added to each well, and then 4 μl of PD-1 protein and 4 μl of PD-L1 protein were added per well, incubated for 15 min at room temperature; and 10 μl of a mixture of anti-Tag1-Eu3+ and anti-Tag2-XL665 was added per well and incubated for 1 h to 4 h at room temperature and the fluorescence signals at 665 nm and 620 nm were measured with an Envison instrument. HTRF rate=(665 nm/620 nm)*104. 8-10 concentrations were detected for each compound and IC50 was calculated by Graphpad software.