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23.2: Introduction to the Innate Immune Response

  • Page ID
    44247
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    Explain immediate and induced innate immune responses

    The immune system comprises both innate and adaptive immune responses. Innate immunity occurs naturally because of genetic factors or physiology; it is not induced by infection or vaccination but works to reduce the workload for the adaptive immune response. Both the innate and adaptive levels of the immune response involve secreted proteins, receptor-mediated signaling, and intricate cell-to-cell communication. The innate immune system developed early in animal evolution, roughly a billion years ago, as an essential response to infection. Innate immunity has a limited number of specific targets: any pathogenic threat triggers a consistent sequence of events that can identify the type of pathogen and either clear the infection independently or mobilize a highly specialized adaptive immune response. For example, tears and mucus secretions contain microbicidal factors.

    What You’ll Learn to Do

    • Describe physical and chemical immune barriers
    • Describe different ways that host organisms recognize and combat pathogens
    • Discuss natural killer cells
    • Summarize how the proteins in a complement system function to destroy extracellular pathogens

    Learning Activities

    The learning activities for this section include the following:

    • Physical and Chemical Barriers
    • Pathogen Recognition
    • Natural Killer Cells
    • Complement System
    • Self Check: The Innate Immune Response

    Contributors and Attributions

    CC licensed content, Original
    • Introduction to the Innate Immune Response. Provided by: Lumen Learning. License: CC BY: Attribution
    CC licensed content, Shared previously

    23.2: Introduction to the Innate Immune Response is shared under a not declared license and was authored, remixed, and/or curated by LibreTexts.

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