TNF-beta is a potent mediator of inflammatory and immune responses. It belongs to the TNF family of ligands and signals through TNFR1 and TNFR2. TNF-beta is produced by activated T and B lymphocytes, and has similar activities to TNF-alpha. Like TNF-alpha, TNF-beta is involved in the regulation of various biological processes including cell proliferation, differentiation, apoptosis, lipid metabolism, coagulation, and neurotransmission. TNF-beta is secreted as a soluble polypeptide, but can form heterotrimers with lymphotoxin-beta, which effectively anchors the TNF-beta to the cell surface. TNF-beta is cytotoxic to a wide range of tumor cells.