Bence Jones protein is a monoclonal

globulin The globulins are a family of globular proteins that have higher molecular weights than albumins and are insoluble in pure water but dissolve in dilute salt solutions. Some globulins are produced in the liver, while others are made by the immune ...

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...

immunoglobulin light chain ] The immunoglobulin light chain is the small Peptide, polypeptide subunit of an antibody (immunoglobulin). A typical antibody is composed of two immunoglobulin (Ig) heavy chains and two Ig light chains. In humans There are two types of light ...

found in the

urine Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (mal ...

, with a molecular weight of 22–24 kDa. Detection of Bence Jones protein may be suggestive of

multiple myeloma Multiple myeloma (MM), also known as plasma cell myeloma and simply myeloma, is a cancer of plasma cells, a type of white blood cell that normally produces antibody, antibodies. Often, no symptoms are noticed initially. As it progresses, bone ...

, or Waldenström's macroglobulinemia. Bence Jones proteins are particularly diagnostic of multiple myeloma in the context of target organ manifestations such as

kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

, lytic (or "punched out") bone lesions,

anemia Anemia (also spelt anaemia in British English) is a blood disorder in which the blood has a reduced ability to carry oxygen. This can be due to a lower than normal number of red blood cells, a reduction in the amount of hemoglobin availabl ...

, or large numbers of

plasma cell Plasma cells, also called plasma B cells or effector B cells, are white blood cells that originate in the lymphoid organs as B cells and secrete large quantities of proteins called antibodies in response to being presented specific substances ca ...

s in the

bone marrow Bone marrow is a semi-solid biological tissue, tissue found within the Spongy bone, spongy (also known as cancellous) portions of bones. In birds and mammals, bone marrow is the primary site of new blood cell production (or haematopoiesis). It i ...

. Bence Jones proteins are present in 2/3 of multiple myeloma cases. The proteins are

s (

paraprotein A myeloma protein is an abnormal antibody (immunoglobulin) or (more often) a fragment thereof, such as an immunoglobulin light chain, that is produced in excess by an abnormal monoclonal proliferation of plasma cells, typically in multiple mye ...

s) and are produced by

neoplastic A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

plasma cells. They can be kappa (most of the time) or lambda. 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

, sometimes induced by

hypercalcemia Hypercalcemia, also spelled hypercalcaemia, is a high calcium (Ca2+) level in the blood serum. The normal range for total calcium is 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), with levels greater than 2.6 mmol/L def ...

from the calcium released as the bones are destroyed, dehydration due to polyuria, amyloidosis or from the light chains themselves. The light chains were historically detected by heating a

specimen (which causes the protein to precipitate) and nowadays by

electrophoresis Electrophoresis is the motion of charged dispersed particles or dissolved charged molecules relative to a fluid under the influence of a spatially uniform electric field. As a rule, these are zwitterions with a positive or negative net ch ...

of concentrated urine. More recently, serum free light chain assays have been utilised 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 and amyloid light chain amyloidosis (AL amyloidosis).

History

The Bence Jones protein was described by the English physician Henry Bence Jones in 1847 and published in 1848.

References

{{Amyloidosis Blood tests Urine tests Hematology