This test measures the amount of immunoglobulins in your blood. Immunoglobulins are also called antibodies. Antibodies are proteins that your immune system makes to fight germs , such as viruses and bacteria . When you're exposed to germs, your body makes unique antibodies that are specifically designed to destroy only those germs.
An immunoglobulins test usually measures three main types of immunoglobulin (Ig) antibodies that do different jobs to protect your health:
- IgM antibodies are the first immunoglobulins your body makes after you're exposed to germs. They provide short-term protection while your body makes other antibodies. IgM antibodies are in your blood and lymph fluid (a watery fluid that carries the cells that fight infections and diseases to all parts of your body).
- IgG antibodies are very important for fighting infections from bacteria and viruses. Most of the immunoglobulins in your blood are IgG. You also have some IgG antibodies in all your body fluids. Your body keeps a "blueprint" of all the IgG antibodies you have made. That way, if you're exposed to the same germs again, your immune system can quickly make more antibodies.
- IgA antibodies protect your respiratory tract (the organs you use to breathe) and your digestive system (the organs you use to eat and digest food) from infections. You have IgA antibodies in your blood, saliva, and gastric "juices."
An immunoglobulins blood test measures the amounts of IgM, IgG, and IgA in your blood to help diagnose different types of health conditions that may affect your immune system.
Other names: quantitative immunoglobulins, total immunoglobulins, IgG, IgM, IgA testing