Protein Electrophoresis and Immunofixation Electrophoresis

Note: this site is for informational purposes only. To view test results or book a test, use the NHS app in England or contact your GP.

A protein electrophoresis and immunofixation electrophoresis test measures and separates different proteins in the blood, urine or sometimes other body fluids using samples such as a blood sample taken from a vein in the arm. It is used to help detect, diagnose and monitor conditions associated with abnormal protein production, including multiple myeloma and other disorders affecting the immune system, kidneys or liver.

Also known as 
Serum Protein Electrophoresis (SPE); Urine Protein Electrophoresis (UPE); IFE 
Formal name 
Serum protein electrophoresis and urine protein electrophoresis 

Why get tested?

To help diagnose and monitor tumours of the antibody producing cells (B lymphocytes) and to diagnose and monitor deficiencies of the immune system

When to get tested?

If your doctor suspects that you have a condition that affects the antibody concentrations in the blood. If you have no symptoms is may be that other test results suggest a problem with antibodies such as a high total protein concentration

Sample required?

A blood sample taken from a vein in your arm; sometimes a random or 24-hour urine sample

Test preparation needed?

No test preparation is needed

What is being tested?

Protein electrophoresis is a method for separating the proteins found in blood (serum) or urine. During the test, an electric current is used to move the proteins across a thin layer of agarose gel. The distances that individual proteins travel depend on their size, shape, and electrical charge. These separated proteins may be detected by the use of a dye that binds to (stains) all of the proteins and reveals a characteristic pattern of bands. Each band indicates the presence of a particular protein or group of proteins, while the size of the band is a rough indication of the quantity. This pattern of bands is converted into a visual graph, showing vertical spikes or peaks where there is a lot of protein and smaller peaks or valleys where there is less. An alternative method called capillary zone electrophoresis (CZE) separates proteins by passing them through a long, thin column, producing a graph that is very similar to the one made by running the protein through an agarose gel.

Specific proteins of interest can be identified by separating the proteins by gel electrophoresis and then adding an antibody. The antibody can recognise individual proteins and sticks to them making a big complex that gets caught in the gel. All the other proteins in the system are washed away and the gel stained so the proteins in question can be identified. This procedure is called immunofixation electrophoresis (IFE) and only performed if the original electrophoresis is abnormal.

The bands seen on protein electrophoresis form characteristic patterns. Alterations to these patterns are associated with a variety of different diseases and conditions. For example in multiple myeloma (a cancer of certain types of white blood cells called plasma cells), the uncontrolled growth and division of a malignant plasma cell leads to the production of large amounts of a single type of immunoglobulin (antibody). In contrast to other proteins in serum, which are typically of a single type, antibodies (immunoglobulins) must differ from each other to be able to recognise bacteria, viruses and other foreign’ substances. Each time the body is exposed to a virus, for example, one plasma cell replicates and makes a group (or clone) of plasma cells to produce antibody to eliminate it. Since our total immunoglobulin represents antibody made by many clones, we refer to it as a polyclonal pattern. When there is a cancer of plasma cells, only one type of antibody is produced, termed a monoclonal pattern. This abnormal protein can be seen as a characteristic band on the electrophoresis gel.

Common questions