Immunoassay for IgG Subclass 1 (IgG1) Antibody in Serum

Why Might You Need This Test?

Your healthcare provider may order this test if you have symptoms or conditions that suggest an abnormal immune response, such as chronic infections, autoimmune diseases, or after receiving certain vaccines. It may also be used to monitor immune function in people with weakened immune systems, like those with HIV or undergoing chemotherapy.

What Does This Test Measure?

The test measures the concentration of IgG1 antibodies in your blood serum. IgG1 is part of the immunoglobulin G (IgG) family, which is the most abundant antibody in your blood. These antibodies help fight off bacteria and viruses by marking them for destruction by other immune cells.

Sample Collection and Preparation

A blood sample is taken from a vein in your arm. The blood is then processed to separate the serum, which is the liquid part containing the antibodies. This serum is sent to a lab for testing using an immunoassay method.

What Are the Possible Results?

Results are typically reported as a concentration value (e.g., grams per liter or milligrams per deciliter). While specific reference ranges can vary by lab, higher or lower levels than expected may indicate different health conditions that your healthcare provider will discuss with you.