Use of antibodies in disease diagnosis and therapy

Immunoassays

Examples of immunoassay include titer of antibodies directed against Epstein-Barr virus or Lyme disease estimated from the blood. In absence of these antibodies it is presumed that either the person is not infected, or the infection occurred a ''very'' long time ago, and the B cells generating these specific antibodies have naturally decayed.

For immunoassays, levels of individual classes of immunoglobulins are measured by nephelometry (or turbidimetry) to characterize the antibody profile of patient.  The Coombs test is also used for antibody screening in blood transfusion preparation. This test is used for antibody screening in antenatal women as well. Immunoassays are used in multiple sclerosis, psoriasis, and many forms of cancer including non-Hodgkin's lymphoma, colorectal cancer, head and neck cancer and breast cancer.

Then there is the use of radiolabelled antibodies that can be used in the diagnosis of diseases as well. These radiolabelled antibodies are used for diagnosis or detection of whole cells, receptors and enzymes. There is also enzyme labelled immune assays.