antigen

noun
an·​ti·​gen | \ ˈan-ti-jən How to pronounce antigen (audio) , -ˌjen\

Definition of antigen

: any substance (such as an immunogen or a hapten) foreign to the body that evokes an immune response either alone or after forming a complex with a larger molecule (such as a protein) and that is capable of binding with a product (such as an antibody or T cell) of the immune response

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Other Words from antigen

antigenic \ ˌan-​ti-​ˈje-​nik How to pronounce antigenic (audio) \ adjective
antigenically \ ˌan-​ti-​ˈje-​ni-​k(ə-​)lē How to pronounce antigenically (audio) \ adverb
antigenicity \ ˌan-​ti-​jə-​ˈni-​sə-​tē How to pronounce antigenicity (audio) \ noun

Did You Know?

An antibody is a protein produced by your immune system to fight outside invaders. Since the enemy substance actually triggers the production of antibodies, such substances are called antigens—anti- being short for antibody, and -gen meaning "producer". (In a similar way, an allergen produces an allergy, and a pathogen produces a pathology or disease.) Antigens are often rodlike structures that stick out from the surface of an invading organism—usually a bacterium or a virus—and allow it to attach itself to cells in the invaded body. But unfortunately for them, in doing so they let the immune system know they're present, and the body is flooded with an army of Pac-Man-like antibodies.

Examples of antigen in a Sentence

Recent Examples on the Web The vaccines administered to babies and children each contain between one and 69 antigens, according to the CDC. Carolyn L. Todd, SELF, "What Parents Need to Know About the Immunization Schedule for Kids," 26 Aug. 2019 So the vaccine uses cell and gene therapy to force those cells to express a specific bacterial antigen on their surface, making them easy for the immune system to identify. Justine Griffin, orlandosentinel.com, "A vaccine for cancer? Tampa company is working on it," 21 Aug. 2019 To create cells for use in regenerative medicine, scientists envision large-scale collections of stem cells with diverse characteristics and specific tissue antigens. Tobias Deuse, The Conversation, "Stem cells could regenerate organs – but only if the body won’t reject them," 19 Aug. 2019 The current vaccine, which principally targets a portion of the virus known as the hepatitis B surface antigen, was introduced in the U.S. in 1989. Quanta Magazine, "Vaccines Are Pushing Pathogens to Evolve," 10 May 2018 These antigens prompt your B-lymphocytes, another type of white blood cell, to churn out antibodies, or proteins that help eliminate pathogens. Patia Braithwaite, SELF, "What Is Herd Immunity, And Why Does It Matter?," 26 Aug. 2019 The same way an athlete develops muscle memory during training, vaccines help your immune system develop memory cells so antibodies can respond better and faster to antigens (any foreign cell or substance that triggers an immune response). CNN, "These dogs are getting a cancer vaccine. If it works, humans could be next," 21 June 2019 If an immune cell binds tightly to an antigen, the cell multiplies. Quanta Magazine, "Breakthrough DNA Editor Born of Bacteria," 6 Feb. 2015 First things first: All vaccines only contain very small amounts of antigens. Carolyn L. Todd, SELF, "What Parents Need to Know About the Immunization Schedule for Kids," 26 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'antigen.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of antigen

1908, in the meaning defined above

History and Etymology for antigen

German, from French antigène, from anticorps antibody + -gène -gen

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Statistics for antigen

Last Updated

18 Oct 2019

Time Traveler for antigen

The first known use of antigen was in 1908

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More Definitions for antigen

antigen

noun
How to pronounce antigen (audio)

English Language Learners Definition of antigen

medical : a harmful substance that causes the body to produce antibodies

antigen

noun
an·​ti·​gen | \ ˈant-i-jən How to pronounce antigen (audio) \

Medical Definition of antigen

: any substance (as an immunogen or a hapten) foreign to the body that evokes an immune response either alone or after forming a complex with a larger molecule (as a protein) and that is capable of binding with a product (as an antibody or T cell) of the immune response

Other Words from antigen

antigenic \ ˌant-​i-​ˈjen-​ik How to pronounce antigenic (audio) \ adjective
antigenically \ -​i-​k(ə-​)lē How to pronounce antigenically (audio) \ adverb

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More from Merriam-Webster on antigen

Spanish Central: Translation of antigen

Nglish: Translation of antigen for Spanish Speakers

Britannica English: Translation of antigen for Arabic Speakers

Britannica.com: Encyclopedia article about antigen

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