Stem Cell Factor (SCF) is a hematopoietic growth factor that exerts its activity at the early stages of hematopoiesis. SCF stimulates the proliferation of myeloid, erythroid, and lymphoid progenitors in bone marrow cultures.Source:Recombinant protein corresponding to 165aa residues from human Stem Cell Factor, expressed in E. coli. Molecular Weight: ~18.9kDBiological Activity:The ED50, as determined by the dose-dependent stimulation of the proliferation of human TF-1 cells, is <2ng/ml, corresponding to a specific activity of >5x10e5units/mg.Endotoxin:<0.1ng/ugStorage and Stability:Lyophilized powder may be stored at -20°C. Stable for 12 months after receipt at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Reconstituted product is stable for 6 months at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Further dilutions can be made in assay buffer.