Fibroblast growth factor 7 (FGF-7), also known as keratinocyte growth factor (KGF), is a member of the fibroblast growth factor (FGF) family. It plays an important role in the regulation of embryonic development, cell proliferation and cell differentiation. Growth factor necessary for normal meristem morphogenesis and active in keratin-forming cells. May be a major paracrine effector of normal epithelial cell proliferation. Recombinant KGF overexpressed in E. coli is about 10 times more active than the natural protein, probably related to the fact that recombinant KGF is not glycosylated.KGF, segment 122-132AA, is a specific binding site for the KGF receptor.KGF is secreted by mesenchymal stromal cells of various origins, and has a strong affinity for heparin.The receptor KGFR belongs to the family of protein tyrosine kinase receptors, which are predominantly distributed in the The receptor KGFR belongs to the protein tyrosine kinase receptor family, which is mainly distributed in epithelial cells. When KGF specifically binds to the receptor KGFR on the membrane of the target cell, it prompts the phosphorylation of the receptor itself, which initiates the intracellular signaling cascade, and then exerts a variety of biological functions, such as participating in the development of tissues and organs, promoting the proliferation of cells, and repairing the damage of tissues.