Stem Cell Factor human, combinant, expressed in Escherichia coli cell culture tested

Catalog Number S7901 Storage Temperature –20 °C

Synonyms: c-Kit Ligand (KL); SCF The product is lyophilized from a 0.2 mm filtered solution in phosphate buffered saline containing 50 mg Product Description bovine serum albumin per mg cytokine. Stem Cell Factor1, also called c-kit Ligand2 (KL) or Mast 3 Cell Growth Factor (MGF), is a peptide growth Predicted molecular mass: ~18.6 kDa factor/cytokine with broad activities, especially related (extracellular domain human SCF; Glu26-Ala189) to hematopoiesis. Among the many activities of SCF are the ability to act on early hematopoietic Purity: >97% (SDS-PAGE) progenitor/stem cells and to stimulate the proliferation and survival of mast cells. Also, SCF is one of the most The biological activity of rhSCF is measured in a cell potent stimulators of multilineage progenitors (CFU- proliferation assay using a human, factor-dependent GEMM) in both human and murine bone marrow 20 cell line, TF-1. ED50 is typically 2.5–10 ng/ml cells.2,4 SCF acts synergistically with other growth factors, including erythropoietin, G-CSF, M-CSF, Endotoxin level: <1.0 EU per mg cytokine (LAL method) GM-CSF, IL-3, and IL-6, to increase the number and 1,2,5 size of colonies of hematopoietic progenitors. SCF Precautions and Disclaimer appears to play an important role in the survival, This product is for R&D use only, not for drug, proliferation, or migration of primordial germ cells and household, or other uses. Please consult the Material melanoblasts during both development6,7 and 8,9 Safety Data Sheet for information regarding hazards maturation. and safe handling practices. Natural, human SCF is a 25–35 kDa glycoprotein 1-3,10 Reconstitution (SDS-PAGE). Under non-denaturing conditions, The contents of the vial may be reconstituted to a stock SCF appears to be a non-covalently linked dimer of 10 solution containing sterile phosphate buffered saline 50–55 kDa. SCF is synthesized as a transmembrane and 0.1% bovine serum albumin to a final concentration protein,11,12 which is then cleaved, presumably at the 13,14 of no less than 10 mg/ml of cytokine. The stock cell surface, to yield a soluble protein. An alternative solutions should be apportioned into working aliquots form of SCF exists whereby the proteolytic cleavage and stored at –70 °C or –20 °C. If aseptic technique is site is spliced out, allowing the transmembrane section used, additional filtration should not be necessary and to remain intact and biologically active SCF (38 kDa) to should be avoided due to possible adsorption of the remain attached to the cell surface.11,13 The cytokine onto the filter membrane. predominant message in many cells is the secreted form of SCF, but the attached (spliced) and secreted Storage forms are expressed at similar levels in some cells. The 15-17 Store the product at –20 °C. For extended storage, receptor for SCF is the c-kit ligand, a transmembrane 150–165 kDa glycoprotein belonging to freeze in working aliquots at –70 °C or –20 °C. the receptor tyrosine kinase subclass III family,18 which Repeated freezing and thawing is not recommended. includes receptors to PDGF and M-CSF. Human SCF is Do not store in a frost-free freezer. 500–1,000 fold less active on murine cells.19 References 1. Zsebo, K.M., et al., Cell, 63, 195 (1990). 11. Huang, E., et al., Cell, 63, 225 (1990). 2. Nocka, K., et al., EMBO J., 9, 3287 (1990). 12. Anderson, D. M., Cell, 63, 235 (1990). 3. Williams, D.E., et al., Cell, 63, 167 (1990). 13. Flanagan, J.G., et al., Cell, 64, 1025 (1991). 4. Broxmeyer, H.E., et al., Blood, 77, 2142 (1991). 14. Huang, E J., et al., Molecular Biology of the Cell, 5. Martin, F.H., et al., Cell, 63, 203 (1990). (1992). 6. Bennett, D., J. Morphology, 98, 199 (1956). 15. Besmer, P., et al., Nature, 320, 415 (1986). 7. Silvers, W., Coat Colors of Mice: A Model for Gene 16. Yarden, Y., et al., EMBO J., 6, 3341 (1987). Action and Interaction, New York: Springer-Verlag, 17. Qiu, F.H., et al., EMBO J., 7, 1003 (1988). p. 206 (1979). 18. Yarden, Y., and Ullrich, A., Annu. Rev. Biochem., 8. Orr-Urtreger, A., et al., Development, 109, 57, 443 (1988). 911(1990). 19. Langley, K.E., et al., Archiv. Biochem. Biophys., 9. Manova, K., et al., Development, 110, 1057 (1990). 295, 21 (1992). 10. Arakawa, T., et al., J. Biol. Chem., 266, 18942 20. Kitamura, T., et al., J. Cell Physiol., 140, 323-334 (1991). (1989).

JF,PHC,MAM 03/09-1

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