Antibody titer is a laboratory test that measures the level of antibodies in a blood sample.
The antibody level in the blood tells your doctor whether or not you have been exposed to an antigen or something that the body thinks is foreign. The body uses antibodies to attack and remove foreign substances.
Abnormal results may be due to:
- Autoimmune disease (like lupus)
- Failure of a vaccine to fully protect you against a certain disease Immune deficiency
- Viral infections
Source: MedlinePlus.gov
