Beta2-microglobulin is a protein found on the surface of most nucleated cells and is in particularly high concentrations on the surface of lymphocytes. It can be detected in both serum and urine. Serum levels are a function of its rate of synthesis, release into the serum and its rate of clearance by the kidneys. B2M is frequently elevated in lymphoproliferative diseases such as multiple myeloma, B-cell lymphoma, and chronic lymphocytic leukemia.
It may also be elevated in cancers of the GI tract, cervix, lung and breast. Benign elevations may be seen in Crohn's Disease, AIDS lymphadenopathy, liver disease, renal disease, renal transplants and inflammatory diseases such as rheumatoid arthritis and SLE.
Beta2-microglobulin is a MEIA AxSYM assay. Samples are serum (preferred), plasma or urine (random or an aliquot of 24 hour urine collection). Urine samples can be analyzed if pre-arranged with the lab.
serum = < 2 mg/L
urine = <0.13 µg/L