Meaning of monoclonal antibody: A monoclonal antibody is a laboratory-made protein engineered to bind one specific target, with uses spanning cancer, autoimmune disease, and infection.

Definition of monoclonal antibody

A monoclonal antibody is an antibody manufactured in a laboratory, engineered so that every copy is identical and binds to one specific target, called an antigen. This precision distinguishes monoclonal antibodies from the antibodies naturally produced by the immune system, which respond to many different sites on a given target at once.

Monoclonal antibodies are used across many areas of medicine. In cancer treatment, some are designed to bind directly to tumor cells or to block signals that support tumor growth, while others carry a drug, toxin, or radioactive substance directly to a tumor. Monoclonal antibodies are also used to treat autoimmune and inflammatory conditions, to prevent transplant rejection, and to treat certain infections.

Because each monoclonal antibody is built to recognize only one target, treatment with one requires that the target it was designed for be present, which is why laboratory testing sometimes confirms a specific target before this type of treatment is used.

Also known as

mAb

Used in a sentence

A monoclonal antibody was added to the treatment regimen after testing confirmed the relevant target was present.

+

Good to know

Monoclonal antibodies are named for a single specific target, so their use in a given condition depends on that target being present, which is why related laboratory testing sometimes precedes treatment.

Word origin

Where “monoclonal antibody” comes from

Formed from Greek monos, meaning single, and klon, meaning a twig or shoot, describing the identical cell lineage, or clone, from which every copy of the antibody is produced.

For learning, not diagnosis. This glossary provides general educational information and is not a substitute for advice from a qualified healthcare professional. If you may be experiencing a medical emergency, contact local emergency services.