Immunoglobulin G (IgG) Subclass 2 Concentration (Serum/Plasma)

What Does This Test Measure?

IgG2 is one of five subclasses of Immunoglobulin G (IgG), a type of antibody in your blood. It plays a role in defending against specific types of bacteria and some viruses. Your body produces IgG2 in response to certain infections or vaccines. Levels can vary depending on your immune response, overall health, and exposure to pathogens.

Why Might You Need This Test?

Doctors may order an IgG2 test if you have symptoms of a weakened immune system, recurrent infections, or if you’re being evaluated for conditions like immunodeficiency, autoimmune diseases, or certain allergies. It can also be part of monitoring treatment for conditions affecting the immune system.

What to Expect Before the Test

No special preparation is usually needed. You may have a small needle inserted into a vein in your arm to draw blood. If you’re nervous, let your healthcare provider know so they can help you relax. The test is quick, and you can return to your normal activities afterward.

What the Results Mean

Results show the concentration of IgG2 in your blood. While reference ranges can vary by lab, lower than expected levels might suggest an immune deficiency, while higher levels could indicate chronic infections, certain diseases, or immune system activation. Your doctor will interpret results in the context of your health history and symptoms.