Technical Data
Tumor Necrosis Factor alpha, Recombinant, Human (TNFa)
Molecular Biology Storage: -70CShipping: Dry Ice
Tumor necrosis factor alpha (TNF-a), also called cachectin, is produced by neutrophils, activated lymphocytes, macrophages, NK cells, LAK cells, astrocytes endothelial cells, smooth muscle cells and some transformed cells. TNF-a occurs as a secreted, soluble form and as a membrane-anchored form, both of which are biologically active. The naturally-occurring form of TNF-a is glycosylated, but non-glycosylated recombinant TNF-a has comparable biological activity. The biologically active native form of TNF-a is reportedly a trimer. Human and murine TNF-a show approximately 79% homology at the amino acid level and crossreactivity between the two species. Two types of receptors for TNF-a have been described and virtually all cell types studied show the presence of one or both of these receptor types.

Biological Activity:
Fully biologically active when compared to standard. The Specific Activity is 2.0 10e7 IU/mg as determined by the cytolysis of murine L929 cells in the presence of Actinomycin D.

Endotoxin: 1EU/ug as determined by LAL method.

Storage and Stability:
Aliquot to avoid repeated freezing and thawing and freeze at -70C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap. Aliquots are stable for at least 12 months.

Molecular Weight:
17.5 kD
Source: Escherichia coli
Purity: ~95% by SDS-PAGE and HPLC analyses.
Concentration: 1mg/ml
Form: Supplied as a lyophilized powder in PBS, pH 7.5. Reconstitute in sterile distilled water or aqueous buffer containing 0.1% BSA to a concentration of 0.1-1mg/ml.

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.
Intended for research use only. Not for use in human, therapeutic, or diagnostic applications.