E. coli-derived human SCF/c-kit Ligand protein Glu26-Ala189, with an N-terminal Met Produced using non-animal reagents in an animal-free laboratory.
>97%, by SDS-PAGE visualized with Silver Staining and quantitative densitometry by Coomassie® Blue Staining.
<0.10 EU per 1 μg of the protein by the LAL method.
N-terminal sequence Analysis
Predicted Molecular Mass
Measured in a cell proliferation assay using TF‑1 human erythroleukemic cells. Kitamura, T. et al. (1989) J. Cell Physiol. 140:323. The ED50 for this effect is 1‑5 ng/mL. The specific activity of Recombinant Human SCF is approximately 564 IU/μg, which is calibrated against recombinant human SCF WHO International Standard (NIBSC code: 91/682).
Formulation, Preparation and Storage
What does CF mean?
CF stands for Carrier Free (CF). We typically add Bovine Serum Albumin (BSA) as a carrier protein to our
Adding a carrier protein enhances protein stability, increases shelf-life, and allows the recombinant
protein to be stored at a more dilute concentration.
The carrier free version does not contain BSA.
What formulation is right for me?
In general, we advise purchasing the recombinant protein with BSA for use in cell or tissue culture, or
as an ELISA standard.
In contrast, the carrier free protein is recommended for applications, in which the presence of BSA
Lyophilized from a 0.2 μm filtered solution in PBS.
Reconstitute at 0.2 mg/mL in sterile PBS.
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below.
Stability & Storage:
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
3 months, -20 to -70 °C under sterile conditions after reconstitution.
Background: SCF/c-kit Ligand
Stem cell factor (SCF), also known as c-kit ligand (KL), mast cell growth factor (MGF), and steel factor (SLF), is a widely expressed 28‑40 kDa type I transmembrane glycoprotein (1). It promotes the survival, differentiation, and mobilization of multiple cell types including myeloid, erythroid, megakaryocytic, lymphoid, germ cell, and melanocyte progenitors (1‑7). SCF is a primary growth and activation factor for mast cells and eosinophils (8). Mature human SCF consists of a 189 amino acid (aa) extracellular domain (ECD), a 23 aa transmembrane segment, and a 36 aa cytoplasmic tail (9). The ECD shows both N‑linked and O-linked glycosylation (10). Proteolytic cleavage at two alternate sites in the extracellular juxtamembrane region releases a 25 kDa soluble molecule which is comparable to the only form produced by Steel-dickie mutant mice (11, 12). An alternately spliced isoform of human SCF lacks 28 aa that encompasses the primary proteolytic recognition site (13). Within the ECD of the long isoform (corresponding to this recombinant protein), human SCF shares 79%‑87% aa sequence identity with canine, feline, mouse, and rat SCF. Rat SCF is active on mouse and human cells, but human SCF is only weakly active on mouse cells (9). Noncovalent dimers of transmembrane or soluble SCF interact with the receptor tyrosine kinase SCF R/c‑kit to trigger receptor dimerization and signaling (14). SCF assists in the recovery of cardiac function following myocardial infarction by increasing the number of cardiomyocytes and vascular channels (15).
Ashman, L.K. (1999) Int. J. Biochem. Cell Biol. 31:1037.
Sette, C. et al. (2000) Int. J. Dev. Biol. 44:599.
Yoshida, H. et al. (2001) J. Invest. Dermatol. Symp. Proc. 6:1.
Erlandsson, A. et al. (2004) Exp. Cell Res. 301:201.
Kapur, R. et al. (2002) Blood 100:1287.
Wang, C.-H. et al. (2007) Arterioscler. Thromb. Vasc. Biol. 27:540.
Bashamboo, A. et al. (2006) J. Cell Sci. 119:3039.
Reber, L. et al. (2006) Eur. J. Pharmacol. 533:327.
Martin, F.H. et al. (1990) Cell 63:203.
Arakawa, T. et al. (1991) J. Biol. Chem. 266:18942.
Majumdar, M.K. et al. (1994) J. Biol. Chem. 269:1237.
Brannan, C.I. et al. (1991) Proc. Natl. Acad. Sci. 88:4671.
Anderson, D.M. et al. (1991) Cell Growth Differ. 2:373.
Lemmon, M.A. et al. (1997) J. Biol. Chem. 272:6311.
Kanellakis, P. et al. (2006) Cardiovasc. Res. 70:117.
Animal-Free Manufacturing Conditions Our dedicated controlled-access animal-free laboratories ensure that at no point in production are the products exposed to potential contamination by animal components or byproducts. Every stage of manufacturing is conducted in compliance with R&D Systems' stringent Standard Operating Procedures (SOPs). Production and purification procedures use equipment and media that are confirmed animal-free.
All molecular biology procedures use animal-free media and dedicated labware.
Dedicated fermentors are utilized in committed animal-free areas.
Protein purification columns are animal-free.
Bulk proteins are filtered using animal-free filters.
Purified proteins are stored in animal-free containers in a dedicated cold storage room.
Low Endotoxin Level.
No impairment of biological activity.
High quality product obtained under stringent conditions.
Which Brands are Currently Available on bio‑techne.com? R&D Systems, Tocris Bioscience and ProteinSimple branded products are available to purchase through bio‑techne.com. ProteinSimple branded instruments and Simple Plex Assays are available to quote. ProteinSimple branded instrument consumables and ACD branded products will be available on bio‑techne.com in the near future. Novus Biologicals branded products are not currently available on bio‑techne.com and can be found at novusbio.com.
Setting the standard in quality research reagents for over 30 years
A trusted leader in quality life science reagents
Your trusted supplier for innovative and high performance life science reagents
Proprietary systems and consumables for simpler, more quantitative and affordable protein analysis
Proprietary RNAscope® technology capable of detecting and quantifying RNA biomarkers in situ at single molecule sensitivity
A world leader in developing liquid biopsy based diagnostics