Interleukin 12, Recombinant, Human (IL-12, Cytotoxic Lymphocyte Maturation Factor 1, CTL Maturation Factor, TcMF, CLMF p35, Natural Killer Cell Stimulatory Factor 1, NFSK1, p35, T cell Stimulating Factor, TSF) (Human 293 Cells)
|Growth Factors, Cytokines||Storage: -20°CShipping: Blue Ice|
Human Cell Expression Cytokines:
Expression of proteins in our Human 293-cell expression system is a cost-effective and scalable production method for high-authenticity, recombinant human proteins.
Functional activities of human proteins depend on proper folding, phosphorylation, disulfide bridge formation, and proteolytic processing or appropriate glycosylation. Ideally, recombinant human proteins are produced in human cells that are more authentic in terms of both physical properties and biochemical functions. However, the current process of human cell expression requires a large quantity of DNA and medium supplemented with bovine serum. Hence, it is often a daunting task to produce sufficient amount of high quality proteins for drug discovery or diagnostic development (1-100mg) at acceptable cost. United States Biological is now supplying a high yield, cost-effective and versatile system to produce active recombinant human proteins in a human cell line to meet the special needs of the broad scientific community and drug discovery industry. In this system, we have broken key bottleneck steps to increase protein production and reduce cost, including
• Engineered human cell line adapted to suspension for growth in serum-free and chemically defined medium
• Proprietary expression vectors driven by strong promoters and signal peptides
• Large scale transient expression with small quantity of DNA
• Rapid creation of stable human cell lines and adaptation to serum-free medium
• Short time to scale up production
• Efficient tag or tag-free purification
Using this expression system, we have produced a large number of highly active human cytokines, kinases and phosphatases. Our technology is particularly suitable for the production of high-authenticity human proteins in medium scale as research and diagnostic reagents, drug screening targets, and therapeutic proteins for preclinical evaluation. Key differences of recombinant human protein production in different systems are illustrated below:
Expression system E. coli Insect cell CHO cell Human cell
Protein folding + ++ +++ ++++
Phosphorylation - ++ +++ ++++
Proteolytic processing - + +++ ++++
Glycosylation - Poor Not human-like Authentic
IL-12 is expressed as a heterodimeric cytokine composed of two glycosylated and
disulfide-linked subunits (p40 cystine linked to p35). Production in human 293 cells offers authentic glycosylation. Cytokines produced in SF9 or SF21 cells have post-translational modifications which are not human-like.
Recombinant Human IL-12 expressed in Human 293 Cells.
The specific activity was determined by the dose-dependent release of IFN-gamma from the
human NK92 cell line in presence of 20ng/ml recombinant IL-2.
Endotoxin: 1EU/ug (LAL)
Storage and Stability:
Lyophilized powder may be stored at -20°C. Stable for 12 months at -20°C. Reconstitute with sterile PBS, 0.1% recombinant HSA (A1327-54A). Aliquot and store at -20°C. Reconstituted product is stable for 6 months at 4°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.
Source: Human 293 cells
Purity: 90% as determined by SDS-PAGE and HPLC.
Form: Supplied as a lyophilized powder from PBS, pH 7.4.
Important Note: This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications without the expressed written authorization of United States Biological.
1. Gately, M. K., et al. (1998) Annu. Rev. Immunol. 16: 495-521. 2. Hodge, D. L., et al. (2002) Mol. Cell. Biol. 22: 1742-1753.