Tumor Necrosis Factor alpha, Recombinant, Human (TNFa)
|Growth Factors, Cytokines||Storage: -20°CShipping: Blue Ice|
Tumor necrosis factor alpha (TNF-a), also called cachectin, consists of 158 amino acids. TNF-a is a 17.5kD factor produced by neutrophils, CD4+ T cells, macrophage, NK cells, LAK cells, astrocytes endothelial cells, and smooth muscle cells. TNF-a is cytolytic and plays an important role in immune regulation including hemorrhagic tumor necrosis/cytotoxicity and inflammation, and in regulation of antiviral and immune proliferative and activation responses. The active form of this protein is a trimer. Additional amino acid, methionine, was attached at N-terminus of the protein.
Amino Acid Sequence:
MVRSSSRTPS DKPVAHVVAN PQAEGQLQWL NRRANALLAN GVELRDNQLV VPSEGLYLIY
SQVLFKGQGC PSTHVLLTHT ISRIAVSYQT KVNLLSAIKS PCQRETPEGA EAKPWYEPIY
LGGVFQLEKG DRLSAEINRP DYLDFAESGQ VYFGIIAL
Measured in a cytotoxicity assay using L929 mouse fibrosarcoma cells in the presence of the metabolic inhibitor actinomycin D. The ED50 for this effect is <0.16ng/ml.
L929 cytotoxicity assay using actinomycin D
Cell Number: 2 x 10,000 cells/well
Incubation: 24hr after sample treatment
Assay Media: 5% FBS media
Cytokine Concentration: 12 pg/ml - 25 ng/ml
Detection method: MTT assay
Storage and Stability:
May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing.. Store at -20°C. Aliquots are stable for at least 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.
Source: Human, Recombinant, E. coli
Purity: > 95% by SDS PAGE. Purified by using conventional chromatography techniques. Endotoxin: 1EU/ug protein (LAL method)
Form: Supplied as a liquid in 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. Ruddle, N.H., et al., Curr. Opin. Immunol. 4: 327-332 (1992). 2. Chicoine, M.R., et al., J. Neurooncol. 35: 249-257 (1997). 3. Wingfield, P., et al., FEBS Lett. 211: 179-184 (1987). 4. Tikhonov, R.V., et al., Russ. J. Bioorg. Chem. 22: 141-144 (1996). 5. Barbara, J.A.J., et al., Proc. Natl. Acad. Sci. USA 83: 4533-4537 (1986).