The MaxDiscovery™ Human TNF-ß ELISA Test Kit is designed for quantitative determination of the concentration of human TNF-ß in serum, plasma, and cell culture supernatant. Human TNF-ß cDNA encodes a 205 amino acid (aa) residue precursor protein with a 34 aa residue signal peptide that is cleaved to generate the mature secreted protein. The biologically active secreted TNF-ß exists as a homotrimer. It has been shown that TNF-ß is also present on the cell surface of activated T, B, and LAK cells as a heterotrimeric complex with lymphotoxin beta (LT-b), a type II membrane protein that is another member of the TNF ligand family. TNF-ß plays a critical role in lymphoid development and in normal host resistance to infection and to the growth of malignant tumors, serving as an immunostimulant and as a mediator of the inflammatory response. Overproduction of TNF-ß has been implicated as playing a role in a number of autoimmune disorders, including multiple sclerosis and insulin-dependent diabetes mellitus. TNF-ß is produced by activated T and B cells, NK cells, astrocytes, and human myeloma cells.