Protein TRAIL (TNF-Related Apoptosis-Inducing Ligand) is a cytokine that belongs to the tumor necrosis factor (TNF) ligand family. TRAIL induces apoptosis in transformed and tumor cells. This protein binds to several members of TNF receptor superfamily including TNFRSF10B/TRAILR2. Thus a binding ELISA assay was conducted to detect the interaction of TRAIL and TNFRSF10B. Briefly, recombinant human TRAIL were diluted serially in PBS, with 0.01%BSA (pH 7.4). Duplicate samples of 100uL were then transferred to TNFRSF10B-coated microtiter wells and incubated for 2h at 37°C. Wells were washed with PBST and incubated for 1h with anti-TRAIL pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody, wells were aspirated and washed 3 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37°C. Finally, add 50μL stop solution to the wells and read at 450nm immediately. The binding activity of TRAIL and TNFRSF10B was shown in Figure 1, and this effect was in a dose dependent manner.