- any of numerous Y-shaped protein molecules produced by B cells as a primary immune defense, each molecule and its clones having a unique binding site that can combine with the complementary site of a foreign antigen, as on a virus or bacterium, thereby disabling the antigen and signaling other immune defenses. Abbreviation: Ab
- antibodies of a particular type collectively.
Origin of antibody
Also called immunoglobulin.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for antibody
For example, though I had chicken pox decades ago, I still have antibody to chicken pox.The ‘HIV-Cured Baby’ Distorts Hope
March 7, 2014
She was not known previously to be HIV infected but on testing was found to have antibody to the virus.Let’s Not Rush to Call the HIV Baby Findings a ‘Cure’
March 5, 2013
The antibody could be synthesized and one could attack any epidemic with confidence.Pariah Planet
I should say the antibody titer has reached the danger point.Category Phoenix
All we've done was inject an antibody against a specific virus.
A quick test-run showed that the antibody was also being regenerated.
One function of the free receptor, the antibody, is always to unite with the chemical substance which caused it to be formed.The Fundamentals of Bacteriology
Charles Bradfield Morrey
- any of various proteins produced in the blood in response to the presence of an antigen. By becoming attached to antigens on infectious organisms antibodies can render them harmless or cause them to be destroyedSee also immunoglobulin
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for antibody
Online Etymology Dictionary, © 2010 Douglas Harper
- A protein substance produced in the blood or tissues in response to a specific antigen, such as a bacterium or a toxin, that destroys or weakens bacteria and neutralizes organic poisons, thus forming the basis of immunity.
- An immunoglobulin present in the blood serum or body fluids as a result of antigenic stimulus and interacting only with the antigen that induced it or with an antigen closely related to it.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
- Any of numerous proteins produced by B lymphocytes in response to the presence of specific foreign antigens, including microorganisms and toxins. Antibodies consist of two pairs of polypeptide chains, called heavy chains and light chains, that are arranged in a Y-shape. The two tips of the Y are the regions that bind to antigens and deactivate them. Also called immunoglobulin
A Closer Look: Like other vertebrates, humans possess an effective immune system that uses antibodies to fight bacteria, viruses, and cancer cells. Antibodies are complex, Y-shaped protein molecules. The immune system's B lymphocytes, which are produced by the bone marrow, develop into plasma cells that can generate a huge variety of antibodies, each one capable of combining with and destroying an antigen, a foreign molecule. Antibodies react to very specific characteristics of different antigens, binding them to the top ends of their Y formation. Once the antibody and antigen combine, the antibodies deactivate the antigen or lead it to macrophages(a kind of white blood cell) that ingest and destroy it. High numbers of a particular antibody may persist for months after an invasion, eventually diminishing. However, the B cells can quickly manufacture more of the same antibody if exposure to the antigen recurs. Vaccines work by training B cells to recognize and react quickly to potential disease molecules.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.