Bence Jones proteins are particularly diagnostic of multiple myeloma in the context of end-organ manifestations such as renal failure, lytic (or "punched out") bone lesions, anemia, or large numbers of plasma cells in the bone marrow of patients. Bence Jones proteins are present in 2/3 of multiple myeloma cases.[2]

The proteins are immunoglobulin light chains (paraproteins) and are produced by neoplastic plasma cells. They can be kappa (most of the time) or lambda.[2] The light chains can be immunoglobulin fragments or single homogeneous immunoglobulins. They are found in urine as a result of decreased kidney filtration capabilities due to renal failure, sometimes induced by hypercalcemia from the calcium released as the bones are destroyed or from the light chains themselves.[citation needed] The light chains have historically been detected by heating a urine specimen (which causes the protein to precipitate) and now by electrophoresis of concentrated urine.[3]

More recently, serum free light chain assays have been utilized in a number of published studies which have indicated superiority over the urine tests, particularly for patients producing low levels of monoclonal free light chains, as seen in nonsecretory multiple myeloma[4][5][6] and AL amyloidosis.[6][7][8][9] This is primarily because of the re-absorption of free light chains in the kidneys, creating a threshold of light chain production which must be exceeded before measurable quantities overflow into the urine. As such, urinalysis is a fickle witness to changing free light chain production.

Human urine

≥95% (SDS-polyacrylamide gel electrophoresis, quantitative densitometry immunoelectrophoresis and double radial immunodiffusion).

~2mg/ml (after reconstitution)

Supplied as a lyophilized, stable white to slightly yellowish powder. No preservative added. Reconstitute with 500ul sterile ddH2O. Dilute further with sterile PBS.

Suitable for use as a reference antigen, calibrator, coating protein and blocking agent in Immunoelectrophoresis, Double RID, ELISA and Western Blot. Other applications have not been tested.

Optimal dilutions to be determined by the researcher.

Lyophilized and reconstituted products are stable for 6 months after receipt at -20°C. Reconstitute with sterile ddH2O. Aliquot to avoid repeated freezing and thawing. Store at -20°C. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.