Glossary · Sinh học
Antibody
A protein of the immune system that circulates in the blood, recognises foreign substances such as bacteria and viruses, and neutralises them. Antibodies are made by B cells.
Antibodies are made by a kind of white blood cell called a B cell. B cells are lymphocytes that mature in the bone marrow.
At the very tip of an antibody molecule is a hypervariable region. That region is what allows many different types of antibody to be made, to respond to all of the antigens that assault the body. An antigen is anything that is foreign to the human body — it can be a virus, it can be a bacterium, and in some cases your own body will appear as foreign.
Antibodies do not act alone. Complement proteins bind to the surfaces of microorganisms, and they are particularly attracted to pathogens that are already bound by antibodies.