Immunoglobulin G (IgG) Subclass 1, Serum or Plasma Concentration

What Does This Test Measure?

IgG1 is one of five subclasses of Immunoglobulin G (IgG), a type of protein in your blood that helps fight infections. This test specifically looks at the concentration of IgG1 antibodies, which are important for long-term immunity. IgG1 antibodies are particularly effective against bacteria and some viruses. Changes in IgG1 levels can sometimes indicate immune system function or response to treatments.

Why Might You Need This Test?

Your healthcare provider may order this test if they suspect an immune system disorder, such as a condition affecting antibody production. It could also be used to monitor treatment responses in conditions like autoimmune diseases or infections.

How Is the Test Performed?

A blood sample is taken from a vein, usually in your arm. The blood is then processed to separate the serum or plasma, where the IgG1 antibodies are measured using a specialized laboratory technique.

What Are Possible Results?

Results are typically reported as a mass concentration in grams per liter (g/L) or milligrams per deciliter (mg/dL). These values help determine if your IgG1 levels are within the expected range for your age and health status.