Fibroblast Growth Factor 7 (FGF7), also known as Keratinocyte Growth Factor (KGF), is a paracrine signaling protein that belongs to the FGF family. It primarily targets epithelial cells and plays crucial roles in wound healing, tissue repair, and embryonic development. FGF7 binds specifically to the FGFR2b receptor isoform, activating downstream signaling pathways that promote cell proliferation, migration, and differentiation. This growth factor is particularly important in skin homeostasis and regeneration, as it stimulates keratinocyte proliferation. FGF7 is produced mainly by mesenchymal cells and acts on neighboring epithelial tissues, making it a key mediator in epithelial-mesenchymal interactions. Its therapeutic potential has been explored in conditions like skin ulcers, pulmonary fibrosis, and mucosal injuries.Besides,Fibroblast Growth Factor Receptor 1 (FGFR1)has been identified as an interactor of FGF7, thus a functional binding ELISA assay was conducted to detect the interaction of recombinant human FGF7 and recombinant human FGFR1. Briefly, FGF7 was diluted serially in PBS with 0.01% BSA (pH 7.4). Duplicate samples of 100 μl were then transferred to FGFR1-coated microtiter wells and incubated for 1h at 37℃. Wells were washed with PBST and incubated for 1h with anti-FGF7 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. The binding activity of recombinant human FGF7 and recombinant human FGFR1 was shown in Figure 1, the EC50?for this effect is 0.018 μg/mL.