Protein Electrophoresis Serum Test

A Protein Electrophoresis Serum Test measures the types of protein in the fluid (serum) part of a blood sample.

Description

The serum protein electrophoresis (SPE) test measures specific proteins in the blood to help identify some diseases. Proteins are substances made up of smaller building blocks called amino acids. Proteins carry a positive or a negative electrical charge, and they move in fluid when placed in an electrical field. Serum protein electrophoresis uses an electrical field to separate the proteins in the blood serum into groups of similar size, shape, and charge.

Used to evaluate disease categories as acute or chronic inflammation, liver disorder, hypogammaglobulinemia, and possible monoclonal gammopathies.

Blood serum contains two major protein groups: albumin and globulin. Both albumin and globulin carry substances through the bloodstream. Using protein electrophoresis, these two groups can be separated into five smaller groups (fractions):

Albumin. Albumin proteins keep the blood from leaking out of blood vessels. Albumin also helps carry some medicines and other substances through the blood and is important for tissue growth and healing. More than half of the protein in blood serum is albumin.

Alpha-1 globulin. High-density lipoprotein (HDL), the good type of cholesterol, is included in this fraction.

Alpha-2 globulin. A protein called haptoglobin, that binds with hemoglobin, is included in the alpha-2 globulin fraction.

Beta globulin. Beta globulin proteins help carry substances, such as iron, through the bloodstream and help fight infection.

Gamma globulin. These proteins are also called antibodies. They help prevent and fight infection. Gamma globulins bind to foreign substances, such as bacteria or viruses, causing them to be destroyed by the immune system. See an illustration of the immune system. 

Each of these five protein groups moves at a different rate in an electrical field and together form a specific pattern. This pattern helps identify some diseases.

What Abnormal Results Mean

Increased alpha-1 globulin proteins may be due to:

• Acute inflammatory disease
• Cancer
• Chronic inflammatory disease (for example, rheumatoid arthritis, SLE)

Decreased alpha-1 globulin proteins may be a sign of:

• Alpha-1 antitrypsin deficiency

Increased alpha-2 globulin proteins may indicate a:

• Acute inflammation
• Chronic inflammation

Decreased alpha-2 globulin proteins may indicate:

• Breakdown of red blood cells (hemolysis)

Increased beta globulin proteins may indicate:

• A disorder in which the body has problems breaking down fats (for example, hyperlipoproteinemia, familial hypercholesterolemia)
• Estrogen therapy

Decreased beta globulin proteins may indicate:

• Abnormally low level of LDL cholesterol
• Malnutrition

Increased gamma globulin proteins may indicate:

• Bone marrow cancer called multiple myeloma
• Chronic inflammatory disease (for example, rheumatoid arthritis)
• Overactive immune system (hyperimmunization)
• Acute infection
• White blood cell cancer called Waldenstrom macroglobulinemia
• Chronic liver disease