Beta 2 Microglobulin, Human Urine

B2M, also known as β2-Microglobulin or CDABP0092, is a component of MHC class I molecules found expression in all nucleated cells (excludes red blood cells). The major function of MHC class I moleculesis is to display fragments of proteins from within the cell to T-cells and cells containing foreign proteins will be attacked. B2M(β2-Microglobulin) is a low molecular weight protein. It was demonstrated that B2M(β2-Microglobulin) was localized in the membranes of nucleated cells and was found to be associated with HL-A antigens. Beta 2-microglobulin is present in small amounts in serum, csf, and urine of normal people, and to a much greater degree in the urine and plasma of patients with tubular proteinaemia, renal failure, or kidney transplants. For the diagnosis of multiple myeloma, the serum β2-microglobulin level is one of the prognostic factors incorporated into the International Staging System. The serum β2-microglobulin level is elevated (>2.7 mg/L) in 75% of patients at the time of diagnosis.