
Antigen - Wikipedia
At the molecular level, an antigen can be characterized by its ability to bind to an antibody's paratopes. Different antibodies have the potential to discriminate among specific epitopes …
Antigen: What It Is, Function, Types, & Testing - Cleveland Clinic
An antigen is anything recognized by your immune system. Antigen tests diagnose viral infections, monitor certain illnesses or look for stem cell compatibility.
Antigen | Definition, Function, Types, & Facts | Britannica
Nov 12, 2025 · Antigen, substance that is capable of stimulating an immune response, specifically activating lymphocytes, which are the body’s infection-fighting white blood cells. In general, …
Antigens: Types, How They Work, Testing, and More
Sep 5, 2025 · An antigen is a molecule that may be recognized by the immune system and trigger an immune response by activating leukocytes (white blood cells) that fight disease.
Antigen Definition, Function, and Types
Oct 25, 2023 · An antigen is a molecule or particle, often found on the surface of cells, viruses, or bacteria, that triggers an immune response because the body recognizes it as foreign or non-self.
What Are Antigens and Antibodies? - sciencenewstoday.org
Aug 5, 2025 · The term “antigen” is short for antibody generator, which offers the first clue about its purpose. Antigens are molecular structures, often proteins or polysaccharides, that are …
Antigen: MedlinePlus Medical Encyclopedia
Jul 8, 2023 · An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the substance, and is trying to …
Antigens and the initiation of an immune response
Antigen A small substance that causes the body to initiate an immune response. Antigens are bound by specific antibodies or cell receptors and can also be presented by cells via MHC …
Antigen: Properties, Structure, Types, Examples - Biology Learner
Sep 4, 2024 · These molecules or substances are called antigens. Antigens (Ag) are substances that are foreign to the body and trigger an immune response, producing antibodies against …
What is an Antigen? - BYJU'S
Antigens are large molecules of proteins, present on the surface of the pathogen- such as bacteria, fungi viruses, and other foreign particles. When these harmful agents enter the body, …