Adaptive Immunity Overview
20 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which function involves the clearance of toxins and neutralization of pathogens by antibodies?

  • Opsonization
  • Cytokine production
  • Toxin neutralization and clearance (correct)
  • Cell-mediated immunity

    • What is the primary role of CD8+ cytotoxic T cells in the immune response?

  • Killing infected or transformed cells (correct)
  • Engaging in opsonization
  • Activating the complement system
  • Producing antibodies

    • Which component of adaptive immunity is primarily responsible for memory and specificity?

  • Cytokines
  • Antigen-presenting cells
  • B and T cells (correct)
  • NK cells

    • Antibody-dependent cell-mediated cytotoxicity (ADCC) is primarily mediated by which type of cell?

    <p>Natural Killer (NK) cells</p> Signup and view all the answers

    What is a primary feature of the lymphatic system in relation to adaptive immunity?

    <p>Filters pathogenic material and supports immune responses</p> Signup and view all the answers

    Which interaction is NOT a part of adaptive immune responses?

    <p>B cell-antibody interactions</p> Signup and view all the answers

    What characteristic allows the immune system to avoid responding to self-antigens?

    <p>Self tolerance</p> Signup and view all the answers

    How do cytokines function in relation to T cells?

    <p>Influence the activity of other immune cells</p> Signup and view all the answers

    Which component is crucial for presenting antigens to T cells?

    <p>MHC molecules</p> Signup and view all the answers

    In which structure does the initiation of immune responses typically occur?

    <p>Lymph nodes</p> Signup and view all the answers

    Which statement best describes the primary role of B cells in adaptive immunity?

    <p>B cells recognize free antigens and produce antibodies.</p> Signup and view all the answers

    What is a key difference between the antigen recognition mechanisms of T cells and B cells?

    <p>T cells require antigen processing, while B cells can recognize antigens directly.</p> Signup and view all the answers

    What characterizes the two pathways of antigen processing for T cell presentation?

    <p>Exogenous antigens are derived from outside the cell; endogenous are produced within the cell.</p> Signup and view all the answers

    How do natural killer (NK) cells relate to adaptive immunity?

    <p>NK cells can contribute to enhancing the overall immune response but are primarily part of innate immunity.</p> Signup and view all the answers

    What outcome results from B cell somatic hypermutation?

    <p>B cells modify their antibodies to improve antigen recognition.</p> Signup and view all the answers

    What role does isotype switching play in B cell function?

    <p>Isotype switching changes the class of antibodies produced by B cells.</p> Signup and view all the answers

    What is the primary function of T helper cells (CD4)?

    <p>To provide assistance and coordinate the immune response.</p> Signup and view all the answers

    What distinguishes MHC I molecules from MHC II molecules?

    <p>MHC I molecules are found on all nucleated cells; MHC II on professional antigen-presenting cells.</p> Signup and view all the answers

    What process allows for the diversity of receptors on T and B lymphocytes?

    <p>Somatic recombination.</p> Signup and view all the answers

    Which statement about the lymphatic system's role in adaptive immunity is correct?

    <p>The lymphatic system helps in the transportation of lymphocytes and antigens to lymph nodes.</p> Signup and view all the answers

    Study Notes

    Adaptive Immunity: Key Elements

    • Adaptive immunity is mediated by lymphocytes (T cells, B cells, and NK cells)
    • B and T cells are antigen-specific with diverse receptors generated by somatic recombination
    • NK cells, while not antigen-specific, are linked with adaptive immunity, mediating antibody-dependent cell-mediated cytotoxicity (ADCC) and releasing cytokines.

    Antigen Recognition

    • B cells recognize free, native antigens directly.
    • T cells recognize processed antigens (proteins broken into peptides) presented on MHC molecules by antigen-presenting cells (APCs). This associative recognition involves information processing.

    Antigen Presentation Pathways

    • Two pathways process antigens for T cell presentation:
      • Exogenous: for antigens external to the cell
      • Endogenous: for antigens produced within the cell
    • Two classes of MHC molecules: MHC I and MHC II
    • Two classes of T cells:
      • Helper T cells (CD4+)
      • Cytotoxic T cells (CD8+)

    Humoral Immunity (B cell-mediated)

    • B cells produce antibodies (humoral immunity) and act as APCs.
    • Antibodies are versions of B cell surface receptors.
    • B cell response initially resembles a reflex action.
    • With T cell help, B cells:
      • Produce more antibodies
      • Modify antibodies to better recognize antigens (somatic hypermutation/affinity maturation)
      • Change antibody tissue distribution and function (isotype switching)

    Cell-Mediated Immunity (T cell-mediated)

    • CD8+ cytotoxic T cells kill infected or cancerous cells displaying non-self or modified self-antigens.
    • CD4+ cells influence the function of other cells through cytokine production.
    • Cell-mediated responses involve interactions of antigen-specific receptors with MHC/peptide complexes.

    Lymphatic System

    • The lymphatic system is crucial for adaptive immunity. It's a low-pressure circulatory system.
    • It collects fluid from tissues, filters out pathogens and empties into veins.
    • It includes lymphatic vessels, lymph nodes, bone marrow, spleen, thymus, and mucosa-associated lymphoid tissue (MALT).
    • Lymph nodes are rich in antigen-presenting cells that bring antigens from the periphery. B cells reside there; T cells circulate through.

    Key Features of Adaptive Immunity

    • Specificity: Response targets a specific antigen only.
    • Memory: Subsequent exposures trigger a faster and stronger response.
    • Self-tolerance: The system does not respond to self-antigens. Self-tolerance depends on selection of antigen-specific B and T cells and post-selection regulation.

    Summary of Interactions

    • Key elements include T cells, B cells, NK cells, APCs, accessory cells, MHC molecules, antibodies, and cytokines.
    • Interactions involve T cell-T cell co-operation, T cell-accessory cell interactions, T cell-APC interactions, T cell-B cell collaborations, and NK cell-antibody interactions.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Description

    Explore the key elements of adaptive immunity, focusing on lymphocytes such as T cells, B cells, and NK cells. Gain insights into antigen recognition and presentation pathways that differentiate exogenous and endogenous antigens. This quiz will enhance your understanding of the mechanisms behind immune responses.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser