Kinds of Antibodies

There are five major kinds of antibodies in the human body. The immune system makes antibodies to respond to the presence of viruses, bacteria, cancerous cells and fungi. The foreign substances are attacked by antibodies so that the immune system can identify and eliminate them.

IgG Antibodies

• Every fluid in the body has IgG antibodies, the smallest kind of antibody. Most antibodies are IgG antibodies. IgG antibodies fight viral and bacterial infections. They are the only ones that can cross the placenta.

IgA Antibodies

• The IgA antibodies exist in the ears, nose, digestive tract, eyes and other parts of the body. These antibodies help fight off external substances that could enter the body. Blood, saliva and tears all have this antibody. A small percentage of people do not make this type of antibody.

IgM Antibodies

• The largest antibody is the IgM antibody, but it makes up no more than 10 percent of all antibodies. When an infection occurs, the IgM antibodies are the first that respond. They are found in lymph fluid and blood.

IgD Antibodies

• Chest-tissue lining and some of the stomach's lining have IgD antibodies in small amounts. Doctors and researchers are unsure of the role they play in the immune system.

IgE Antibodies

• The mucous membranes, skin and lungs have IgE antibodies. When the body is subjected to animal dander, pollen and fungus, IgE antibodies are produced and sent to attack the foreign substances. People with allergies frequently have high levels of IgE antibodies.