FAS (Tumor necrosis factor receptor superfamily member 6) belongs to the tumor necrosis factor receptor superfamily. FAS contains a death domain, which has been shown to play a central role in the physiological regulation of programmed cell death. A binding ELISA assay was conducted to detect the ass°Ciation of FAS with TNFa. Briefly, FAS were diluted serially in PBS, with 0.01%BSA (pH 7.4). Duplicate samples of 100uL FAS were then transferred to TNFa-coated microtiter wells and incubated for 2h at 37°C. Wells were washed with PBST and incubated for 1h with anti-FAS 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 FAS and TNFa was shown in Figure 1, and this effect was in a dose dependent manner.