Antibody titer
Key points
- A test to measures the presence and amount of antibodies in blood against a particular type of tissue, cell, or substance.
- Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand.
- When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation.
- The antibody level in the blood is a reflection of the body's past experience or exposure to an antigen, or something that the body does not recognize as belonging to itself.
Alternative names
Titer - antibodies; Serum antibodies
Definition
A test to measures the presence and amount of antibodies in blood against a particular type of tissue, cell, or substance.
How the test is performed
Blood is drawn from a vein, usually from the inside of the elbow or the back of the hand. The puncture site is cleaned with antiseptic, and an elastic band is placed around the upper arm to cause the vein to swell with blood.
A needle is inserted into the vein, and the blood is collected in air-tight vials or a syringe. During the procedure, the band is removed to restore circulation. Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.
How to prepare for the test
No special preparation is necessary for this test.
How the test will feel
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed
The antibody level in the blood is a reflection of the body's past experience or exposure to an antigen, or something that the body does not recognize as belonging to itself. The body uses antibodies to attack and eliminate the foreign matter.
Every living cell has different protein markers on its surface. The body's immune system identifies those cells that are not part of itself by these surface proteins.
Occasionally, the body makes an error and begins to recognize its own tissue as being non-self, or foreign. This leads to an immune response against that tissue type, cell, or substance that is part of the body. This is known as autoimmunity.
Levels of antibodies in the blood (also known as the antibody titer) are measured to determine:
- the strength of an immune response to the body's own tissue in diseases such as SLE, and other autoimmune disorders.
- the need for a booster immunization, or if a recent administration caused a strong enough response from the immune system, bringing your antibody titer against a particular disease up to a preventative level.
Normal Values
This depends of the antibody being tested. If your health care provider is testing for antibodies against your own tissue, then the normal value would be zero or negative.
Written and revised by
Gerald Hurowitz, M.D.
Our doctors write and review articles for accuracy and keep them up to date.
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