Fibroblast Growth Factor 7 (FGF7), also known as Keratinocyte Growth Factor (KGF), is a member of the fibroblast growth factor family. It is primarily secreted by mesenchymal cells and acts as a paracrine factor to specifically stimulate the proliferation, migration and differentiation of epithelial cells. FGF7 binds to the FGF receptor 2IIIb isoform on epithelial cell surfaces, activating downstream signaling pathways including MAPK and PI3K/AKT, which regulate tissue repair, skin regeneration and embryonic development. Dysregulation of FGF7 is associated with wound healing disorders, inflammatory skin diseases and tumor progression. FGF7 interacts with Decorin (DCN), a small leucinerich proteoglycan in the extracellular matrix, which modulates its bioavailability and signaling activity. Briefly, DCN was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to FGF7-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-DCN pAb, then aspirated and washed 3 times. After incubation with HRP labelled secondary antibody for 1h at 37℃, 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 450/630nm immediately. Measured by its binding ability in a functional ELISA. When recombinant human FGF7 is lmmobilized at 2 μg/mL(100 μLwell), the concentration of DCN that produces 50% optimal binding response is found to be approximately 0.013 μg/mL.