TGF-β1 (Transforming growth factor beta 1) is a multifunctional set of peptides that controls proliferation, differentiation, and other functions in many cell types. TGF beta 1 has been shown to interact with TGF beta receptor 1, Decorin, LTBP1 and so on. Thus we have conducted a binding ELISA assay to detect the interaction of recombinant human TGF-β1 with recombinant human LTBP1. Briefly, TGF-β1 were diluted serially in PBS, with 0.01%BSA (pH 7.4). Duplicate samples of 100uL were then transferred to LTBP1-coated microtiter wells and incubated for 2h at 37°C. Wells were washed with PBST and incubated for 1h with anti-LTBP1 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 TGF-β1 with LTBP1 was shown in Figure 1 and this effect was in a dose dependent manner.