Stem Cell Factor (SCF) is a cytokine made by fibroblasts and endothelial cells. SCF binds to the receptor known as c-Kit (CD117) and is thought to play a critical role in the maintenance or survival of hematopoietic stem cells. SCF shows no activity on murine cells, but murine and SCF are active on cells. Recombinant SCF is a nonglycosylated Protein, containing 164 amino acids, with a molecular weight of 18.3 kDa.