How do Antibodies Work?

Antibodies circulate in the blood stream and can appear anywhere throughout the body. If circulating antibodies come in contact with the target or antigen they were generated to fight, then the antibodies bind to the target. Depending on the antigen, the binding may impede the biological process causing the disease or may recruit macrophages to destroy the foreign substance.
At the molecular level, antibodies are known to be shaped like the letter Y, with a reactive site at the tip of each branch so that antibodies can become attached to antigens on the basis of their molecular shape. The production of antibodies can be used to explain normal recovery from infection by bacteria or viruses, immunity to subsequent infection to the same organism, and susceptibility to other micro-organisms.

