Granulocyte-Colony Stimulating Factor (G-CSF) is a growth factor that is considered the most potent inducer of terminal differentiation to granulocytes and macrophages of leukemic myeloid cell lines. The synthesis of G-CSF can be induced by bacterial endotoxins, TNF, IL-1 and GM-CSF. Prostaglandin E2 inhibits the synthesis of G-CSF, while in epithelial,endothelial, and fibroblastic cells, secretion of G-CSF is induced by IL-17. and G-CSF are cross-reactive. Recombinant G-CSF is a non-glycosylated Protein, containing 175 amino acids, with a molecular weight of 18.8 kDa.