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Guilherme Mazui

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What is the Difference Between Hapten and Antigen?

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The main difference between a hapten and an antigen lies in their ability to induce an immune response.

An antigen is a substance capable of inducing an immune response, binding specifically to an antibody or a T-cell receptor. Antigens can be proteins, carbohydrates, lipids, or nucleic acids. A complete antigen is one that both induces an immune response and reacts with the products of it, such as antibodies.

On the other hand, a hapten is an incomplete antigen that is unable to induce an immune response alone but can react with the products of it, like antibodies. Haptens are small molecules that can elicit an immune response only when attached to a large carrier, such as a protein. The carrier typically does not elicit an immune response by itself.

In summary:

  • Antigens can induce an immune response and bind specifically to an antibody or a T-cell receptor.
  • Haptens are incomplete antigens that cannot induce an immune response alone and require a carrier to elicit an immune response.
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  • What is the Difference Between Hapten and Antigen?
  • Comparative Table: Hapten vs Antigen

    • Comparative Table: Hapten vs Antigen

    Here is a table comparing haptens and antigens:

    Feature Hapten Antigen
    Definition A hapten is an incomplete antigen that can elicit an immune response only when attached to a large carrier. An antigen is a foreign molecule that can trigger the host immune system to produce specific antibodies.
    Immune Response Haptens cannot trigger an immune response on their own, but they can sensitize the body towards hypersensitivity and autoimmune responses. Antigens induce an immune response when detected by immune system cells.
    Antibody Binding Both haptens and antigens have the ability to bind to antibodies. Antigens can bind to antibodies, leading to the activation of T lymphocytes and phagocytic mechanisms, which degrade or eliminate the foreign particle.
    Examples Haptens include small molecules that can bind to carrier proteins to form adducts, which are complete antigens. Complete antigens are formed when haptens bind to carrier proteins, creating an adduct that can initiate an immune response.

    Both haptens and antigens are recognized by the immune system, but they differ in their ability to trigger an immune response. Haptens require a carrier protein to form a complete antigen, while antigens can induce an immune response on their own.

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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.