Definition - What does Antigen mean?
An antigen is a substance that causes the human body's immune system to generate antibodies in response to that substance entering the body. White blood cells called lymphocytes respond to the foreign substance by generating particular antibodies that attack the antigen.
WorkplaceTesting explains Antigen
An antigen is a primary part of the human immune system. It has a particular shape attributed to it and, similarly, the antibody needs to be a particular shape in order for a connection to be made and infection combat to begin.
Immunization against infectious diseases works on this basis. When a person has had a specific infection in the past and is exposed to it again,the body's immune system recognizes the antigen. The immune system initiates the production of the same shaped antibodies to protect the body from further infection. If an infectious disease is likely to spread in the workplace, immunizations can be performed to mitigate the effects of the disease.
This antigen reaction is also used in some types of drug test to identify past drug ingestion when the actual drug presence is not identified in a sample.