The TNF Family

TNF-α is secreted by macrophages, monocytes, neutrophils, T-cells (principally CD4+), and NK-cells. Many transformed cell lines also secrete TNF-α. Monomeric mouse TNF-α is 156 amino acid protein (N-glycosylated) with a reported molecular weight of 17.5 kD protein. TNF-α forms multimeric complexes; stable trimers are most common in solution. A 26 kD membrane form of TNF-α has also been described. TNF-α binding to surface receptors elicits a wide array of biologic activities including: cytolysis and cytostasis of many tumor cell lines in vitro, hemorraghic necrosis of tumors in vivo, increased fibroblast proliferation, and enhanced chemotaxis and phagocytosis in neutrophils. The TN3-19.12 antibody reacts with mouse, rat, and rabbit tumor-necrosis factor-α (TNF-α) proteins. The TN3-19.12 antibody can neutralize the bioactivity of natural or recombinant TNF-α.