antibody

[an-ti-bod-ee]

noun

plural

antibodies 

1. 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. Ab

2. antibodies of a particular type collectively.

antibody

/ ˈæntɪˌbɒdɪ /

noun

1. 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 destroyed See also immunoglobulin

antibody

1. 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.

2. Also called immunoglobulin

Word History and Origins

Origin of antibody¹

First recorded in 1895–1900; anti- + body

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.

Example Sentences

But it is thought that young calves are particularly vulnerable when they are being weaned, and when the immune-boosting antibodies from the mother's milk decline.

From BBC

Once treated, these animals may carry antibodies to the virus that makes them resistant to reinfection, at least temporarily.

From Los Angeles Times

Grant funding, she said, “was how we bought the antibodies we needed for experiments, how we purchased our reagents and our consumable supplies.”

From Los Angeles Times

Very young babies rely on antibodies acquired during gestation and herd immunity to protect them from measles, which killed roughly 400 children every year in the U.S. before the combined MMR vaccine’s introduction in 1971.

From Los Angeles Times

“Vaccinating during pregnancy is incredibly helpful, because moms can make the antibodies and transfer those antibodies across the placenta,” Singh said.

From Los Angeles Times

Related Words

• bacterium 
• bug 
• disease 
• microbe 
• microorganism 
• pathogen 
• virus