Antibodies are blood proteins that are produced in response to, and to counteract a specific antigen (toxins or other harmful substances that enter the body). The immune system produces antibodies to stop antigens from harming the body. Antigens could be viruses, bacteria, parasites or other chemicals.
Antibodies, also known as immunoglobulins, are glycoproteins (Y shaped proteins) that help to stop antigens from invading the body. When antigens enter the body, the immune system immediately springs into action. Antibodies circulate in the blood in search of harmful antigens. Once the antigen as be located, antibodies stick to these invaders and then identify exactly what type of antigen is to be dealt with. This information is then relayed to the immune system, to ensure the antigen can be destroyed. Each antibody or immunoglobulin is uniquely made for each specific type of antigen.
Once antibodies are produced, they will remain circulating in the blood for months after an infection is eradicated. It is this process that creates a period of ‘immunity’ to specific antigens. The production of antibodies is the basis for the creation of vaccines. Most vaccines or immunisations are made with a weak or diluted form of an antigen, not sufficient enough to make a person ill, but enough to instigate the production of an antibody. As soon as the antibody is created, the body is ready for any potential attack from the corresponding antigen, meaning an infection can be stopped before any harmful effects can be felt.