ABO Blood Types
· An antigen is any substance that causes your immune system to produce antibodies against it, because the immune system does not recognize the substance and is trying to fight it off. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, pollen, toxins, and cells from a transplanted body organ. An antigen may also form inside the body as with cancer cells. Typical an antigen triggers the immune system to produce antibodies.
· Antibodies are proteins typically produced by specialized B cells when they are triggered by an antigen. Antibodies are elite and specialized immune-system fighters that act against that specific antigen and attempt to neutralize or kill it. Think “green berets.”