TNFRSF7(Tumor necrosis factor receptor superfamily member 7), also known as CD27 antigen, is a member of the TNF-receptor superfamily. This receptor is thought to be involved in tumor necrosis factor-activated receptor activity by binding with TNFs. Thus, a binding ELISA assay was conducted to detect the association of TNFRSF7 with TNFb. Briefly, recombinant human TNFRSF7 were diluted serially in PBS with 0.01% BSA(pH 7.4). Duplicate samples of 100ul were then transferred to TNFb-coated microtiter wells and incubated for 2h at 37°C. Wells were washed with PBST and incubated for 1 h with anti-TNFRSF7 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 TNFRSF7 with TNFb was shown in Figure 1 and , the EC50?for this effect is 0.20ug/mL.