Analysis Note

The specific activity was determined by the dose-dependent cytotoxity of the TNF alpha sensitive cell line L-929 in the presence of actinomycin D.

Application

Tumor Necrosis Factor-α (TNF-α) human has been used In induction of netting neutrophils by anti-neutrophil cytoplasmic antibody and to study its effect on platelet activation and formation of monomeric C-reactive protein.To study the effect of TNF-α on miR-221 and fractalkine expression.To induce inflammatory cell responses.In NF-κB luciferase reporter assay.

Tumor Necrosis Factor-a human has been used: as a permeability inducing agent for endothelial cell monolayer permeability assayas a reactive oxygen species inducer in primary rat cardiac microvascular endothelial cells (RCMVECs)in the activation of nuclear factor kappa B (NF-κB) in human embryonic kidney cells (HEK293), neuroblastoma SH-SY5Y cells and HeLa cellsin the stimulation of the human keratinocyte cell line(HaCaT) and human coronary artery endothelial cells (HCAECs)

Biochem/physiol Actions

Tumor Necrosis Factor-α (TNF-α) is a potent pro-inflammatory cytokine that plays a role in the rheumatoid arthritis pathology, psoriatic arthritis (PsA) and psoriasis. It stimulates interleukins IL-1 and IL-6. Polymorphism in the TNF-α gene is associated with destructive arthropathy in PsA. The post-translational modifications in TNF-a is crucial for its functionality.

Tumore necrosis factor-α (TNF-α), also known as cachectin, is expressed as a 26 kDa membrane bound protein and is then cleaved by TNF-α converting enzyme (TACE) to release the soluble 17 kDa monomer, which forms homotrimers in circulation. TNF-α plays roles in antitumor activity, immune modulation, inflammation, anorexia, cachexia, septic shock, viral replication and hematopoiesis. TNF-α is expressed by a great variety of cells, with numerous inductive and suppressive agents. Primarily, TNF-α is produced by macrophages in response to immunological challenges such as bacteria (lipopolysaccharides), viruses, parasites, mitogens and other cytokines. TNF-α is cytotoxic for many transformed cells (its namesake activity) but in normal diploid cells, it can stimulate proliferation (fibroblasts), differentiation (myeloid cells) or activation (neutrophils). TNF-α also shows antiviral effects against both DNA and RNA viruses and it induces production of several other cytokines. Although TNF-α is used in clinical trials as an antitumor agent, Sigma′s cytokine, growth factor and hormone products are for research only. TNF-α and the related molecule TNF-β (LT-α) share close structural homology with 28% amino acid sequence identity and both activate the same TNF receptors, TNFR1 and TNFR2. Mouse and human TNF-α share 79% amino acid sequence identity. Unlike human TNF-α, the mouse form is N-glycosylated.

General description

The TNFα (tumor necrosis factor α) gene is mapped to human chromosome 6p21.33. TNFα is a member of TNF superfamily. TNF-α has a palmitoyl group in the cysteine residue and is phosphorylated in the transmembrane region serine residue.

Packaging

10 µg in poly bottle

Preparation Note

Tumor Necrosis Factor-α (TNF-α) is expressed in human HEK 293 cells and has been shown to be predominantly a glycosylated, non-covalently linked homotrimer with a molecular mass of 51 kDa (gel filtration). Production in human 293 cells offers authentic glycosylation. Glycosylation contributes to stability in cell growth media and other applications.