TLR2 is a member of TLR family which is type I transmembrane proteins with a large number of extracellular leucine-rich repeats (LRRs) and a cytoplasmic Toll/IL-1 receptor (TIR) domain. Human TLR2 is synthesized as a 784 amino acid precursor that contains a signal sequence (aa 1-18), an extracellular domain (aa 19-588) with approximately 20 LRRs, a transmembrane segment (aa 589-609), and a cytoplasmic TIR domain (aa 610-784). The receptor is expressed on a number of cell types including monocytes, dendritic cells, neutrophils, B cells, endothelial cells and hepatocytes. TLR2 stimulation induces mTORC1 activation through TIRAP, which is essential for TLR2-mediated IFN-γ production. Thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human TLR2 and recombinant human TIRAP. Briefly, TLR2 were diluted serially in PBS, with 0.01% BSA (pH7.4). Duplicate samples of 100 ul were then transferred to TIRAP-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-TLR2 pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody, wells were aspirated and washed 5 times. With the addition of substrate solution, wells were incubated 15-25 minutes at 37℃. Finally, add 50 µL stop solution to the wells and read at 450 nm immediately. The binding activity of TLR2 and TIRAP was shown in Figure 1, and this effect was in a dose dependent manner, the EC50 was 0.013 ug/ml.