Cell signaling through the PD-1 receptor upon binding the PD-L1 ligand attenuates immune responses and is exploited by both tumors and viruses. The PD-1[Biotinylated]: PD-L1 Inhibitor Screening Assay Kit is designed for screening and profiling inhibitors of this signaling. This kit comes in a convenient 384-well format with biotin-labeled PD-1, purified PD-L1, streptavidin-labeled HRP, and assay buffer for 400 binding reactions. The key to this kit is the high sensitivity of detection of biotin-labeled PD-1 by streptavidin-HRP. Only a few simple steps on a microtiter plate are required for the assay. First, PD-L1 is coated on a 384-well plate. Next, PD-1 is incubated with PD-L1 on the plate. Finally, the plate is treated with streptavidin-HRP followed by addition of an HRP substrate to produce chemiluminescence, which can then be measured using a chemiluminescence reader.

PBS (Phosphate buffered saline)

Luminometer or fluorescent microplate reader capable of reading chemiluminescence

Rotating or rocker platform

Adjustable micropipettor and sterile tips

1. Lin, D., et al. Proc Natl Acad Sci U.S.A. 2008, 105: 3011-3016.

2. Keir, M.E., et al. Annu. Rev. Immunol. 2008, 26: 677-704.