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Guilherme Mazui

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What is the Difference Between Antigen and Antibody?

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The main difference between an antigen and an antibody lies in their roles in the immune system.

An antigen is a foreign substance that enters the body, such as bacteria, viruses, fungi, allergens, venom, and other various toxins. When an antigen enters the body, the immune system recognizes it as a foreign invader and triggers a response against it.

An antibody, also known as an immunoglobulin, is a protein produced by the immune system to attack and fight off antigens. Antibodies are Y-shaped proteins produced by immune cells called B cells. Each antibody contains a paratope that recognizes a specific epitope on an antigen, acting like a lock and key binding mechanism. This binding helps to eliminate antigens from the body, either by direct neutralization or by 'tagging' for other arms of the immune system.

In summary:

  • Antigens are foreign substances that trigger an immune response in the body.
  • Antibodies are proteins produced by the immune system to identify, attack, and destroy antigens.

Antigens and antibodies play crucial roles in vaccinations. Vaccines contain antigens that stimulate the immune system to produce specific antibodies against the antigens, which in turn helps protect the body from future infections.

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  • What is the Difference Between Antigen and Antibody?
  • Comparative Table: Antigen vs Antibody

    • Comparative Table: Antigen vs Antibody

    Here is a table highlighting the differences between antigens and antibodies:

    Feature Antigen Antibody
    Definition An antigen is a molecule that interacts with the immune system, triggering a response. An antibody is a Y-shaped protein produced by the immune system in response to an antigen.
    Function Antigens are typically foreign substances that prompt the body to produce antibodies. Antibodies, also known as immunoglobulins, bind to specific antigens to neutralize or tag them for attack by the immune system.
    Structure Antigens have distinct surface features, or epitopes, that result in specific responses. Each antibody contains a paratope that recognizes a specific epitope on an antigen, acting like a lock and key binding mechanism.
    Types There are two main types of antigens: heteroantigens (foreign to the body) and autoantigens (created by the body). There are five main types of antibodies (immunoglobulins): IgG, IgM, IgA, IgE, and IgD.
    Examples Antigens can include allergens, bacteria, viruses, and fungi. Examples of antibodies include IgG, IgM, IgA, IgE, and IgD.

    In summary, antigens are molecules that trigger an immune response, while antibodies are proteins produced by the immune system to bind to specific antigens, helping to eliminate them from the body.

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    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.