Intro to Immunology - Lymphocytes
45 Questions
2 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

What characterizes the adaptability of the adaptive immune response?

  • It has a fixed number of antigens it can recognize.
  • It does not change with new exposures.
  • It only responds to naturally occurring antigens.
  • It can target a diverse range of antigens. (correct)

    • Which of the following best describes the concept of self/non-self discrimination in the adaptive immune response?

  • All antigens are treated as non-self by the immune system.
  • Responses are primarily against non-self antigens. (correct)
  • The immune system responds to both self and non-self antigens.
  • The system often attacks self antigens leading to autoimmune diseases.

    • What type of cells do B lymphocytes differentiate into upon activation?

  • T helper cells.
  • Plasma cells. (correct)
  • Memory cells.
  • Cytotoxic T cells.

    • What is the primary function of T cytotoxic (Tc) cells in the adaptive immune response?

    <p>To destroy virus-infected and tumor cells.</p> Signup and view all the answers

    What is an important characteristic of the memory aspect of the adaptive immune response?

    <p>It enables a rapid and vigorous response upon re-exposure to the same antigen.</p> Signup and view all the answers

    What role do T helper (Th) cells play in the adaptive immune response?

    <p>They assist in activating B lymphocytes and other immune cells.</p> Signup and view all the answers

    How does the adaptive immune response exhibit specificity?

    <p>It targets only specific foreign antigens.</p> Signup and view all the answers

    What distinguishes plasma cells from B lymphocytes?

    <p>Plasma cells secrete antibodies.</p> Signup and view all the answers

    What is the significance of memory in the context of vaccines?

    <p>Vaccines stimulate long-term memory against specific antigens.</p> Signup and view all the answers

    What are T regulatory cells primarily responsible for?

    <p>Preventing autoimmunity</p> Signup and view all the answers

    Which type of T cell is often described as 'MHC class II-restricted'?

    <p>T regulatory cells</p> Signup and view all the answers

    What is required for the activation of naïve T cells in addition to peptide and MHC?

    <p>Co-stimulatory signals from APCs</p> Signup and view all the answers

    Which of the following cells are considered antigen-presenting cells?

    <p>Dendritic cells</p> Signup and view all the answers

    What do naïve T lymphocytes become upon activation?

    <p>Both effector and memory cells</p> Signup and view all the answers

    What is the primary function of antigen-presenting cells (APCs) in relation to T cells?

    <p>To ingest and present antigens</p> Signup and view all the answers

    What differentiates T H1 cells from T H2 cells?

    <p>The types of cytokines they produce</p> Signup and view all the answers

    Which of the following accurately describes the interaction necessary for T cell activation?

    <p>Peptide binding plus co-stimulatory signals</p> Signup and view all the answers

    Which of the following is NOT a role of antigen-presenting cells (APCs)?

    <p>Producing antibodies</p> Signup and view all the answers

    What is the primary outcome of the recombination process in developing B cells?

    <p>It generates a unique variable region for each antibody.</p> Signup and view all the answers

    Which type of interaction is necessary for class-switching in B cells?

    <p>CD40 and CD40 ligand interaction</p> Signup and view all the answers

    What determines the specific functional properties of each antibody isotype?

    <p>The constant region of the heavy chain</p> Signup and view all the answers

    In the context of antibody formation, what does class-switching allow for?

    <p>Linking of the same variable region to different constant regions</p> Signup and view all the answers

    Which of the following best describes the mechanism used to create diversity in light-chain genes?

    <p>Random selection and recombination of gene segments</p> Signup and view all the answers

    What does the term 'intervening regions' refer to in antibody formation?

    <p>Regions that are spliced out during antibody formation</p> Signup and view all the answers

    How does a B cell maintain specificity while undergoing class-switching?

    <p>By keeping the same variable region attached to different Fc portions</p> Signup and view all the answers

    Which of the following classes of antibodies are typically found on naïve B cells?

    <p>IgM and IgD</p> Signup and view all the answers

    What is one characteristic of the heavy-chain locus in developing B cells?

    <p>It involves random selection of variable, diversity, and joining segments.</p> Signup and view all the answers

    What is the primary role of B lymphocytes in the immune system?

    <p>To produce antibodies that combat pathogens</p> Signup and view all the answers

    Which of the following best describes T lymphocytes' mechanism of action?

    <p>They recognize pathogens through a receptor/ligand interaction.</p> Signup and view all the answers

    How do lymphocyte clones contribute to the adaptive immune response?

    <p>Each clone has the potential to recognize different antigens.</p> Signup and view all the answers

    Which of the following statements about antibodies is true?

    <p>Antibodies have numerous applications in medicine and biotechnology.</p> Signup and view all the answers

    What is a key aspect of the interaction between T cells and other cell types?

    <p>T cells require direct contact to exert their functions.</p> Signup and view all the answers

    In the context of adaptive immunity, how do T cells specifically contribute?

    <p>They initiate and orchestrate immune responses.</p> Signup and view all the answers

    Which type of lymphocyte is primarily responsible for recognizing and responding to self-antigens?

    <p>T lymphocytes in normal response</p> Signup and view all the answers

    Why is the understanding of antibodies critical for medical professionals?

    <p>Antibodies are frequently involved in diagnosis and treatment applications.</p> Signup and view all the answers

    What is a major implication of lymphocyte heterogeneity in the immune response?

    <p>It allows recognition of a wide variety of antigens.</p> Signup and view all the answers

    What is the primary method of instruction for the immunology session?

    <p>Lecture</p> Signup and view all the answers

    Which process generates diversity in antigen receptors for B and T cells?

    <p>VDJ Recombination</p> Signup and view all the answers

    What do B and T cell antigen receptors consist of?

    <p>Two Protein Chains and a Variable Domain</p> Signup and view all the answers

    Which statement about immunoglobulin isotypes is correct?

    <p>Each isotype has distinct properties and functions.</p> Signup and view all the answers

    Which T cell type is primarily responsible for cytotoxic functions?

    <p>Cytotoxic T cells</p> Signup and view all the answers

    Which of the following is NOT a step in T cell activation?

    <p>Clonal Selection</p> Signup and view all the answers

    MHC Class I molecules present antigenic peptides primarily to which type of T cell?

    <p>Cytotoxic T cells</p> Signup and view all the answers

    How are antigenic peptides for MHC Class II generated?

    <p>Endocytosis of extracellular proteins</p> Signup and view all the answers

    Which sub-lineage of Helper T cells is associated with promoting IgE production?

    <p>Th2</p> Signup and view all the answers

    Study Notes

    Introduction to Immunology - Lymphocytes

    • Session directed by James Proffitt, PhD, on July 31, 2024, led by Lonnie Lybarger, PhD, focusing on cellular and molecular medicine.
    • Recommended readings from "Basic Immunology: Functions and Disorders of the Immune System" offer supplementary information, notably chapters 3-8.

    Learning Objectives

    • Understand the structure of antigen receptors on B and T cells, including protein chains and domains.
    • Comprehend VDJ recombination, the process that generates antigen receptor diversity.
    • Explain isotype (class) switching of immunoglobulins.
    • Identify properties and functions of various antibody isotypes.
    • Recognize effector functions of different T cells: helper (CD4+), cytotoxic (CD8+), and regulatory T cells.
    • Describe T cell activation, emphasizing the roles of antigen-presenting cells (APCs) and costimulation.
    • Learn how antigenic peptides for MHC Class I and Class II are generated, affecting immune surveillance.
    • Understand lymphocyte clonal diversity, enabling recognition of both foreign and self-antigens, foundational to adaptive immunity.

    Key Features of the Adaptive Immune Response

    • Specificity: Responses are targeted against specific antigens.
    • Adaptability: Able to respond to a vast array of antigens, including non-naturally occurring ones.
    • Self/Non-self Discrimination: Primarily targets foreign antigens, avoiding attacks on self-antigens.
    • Memory: Records previous encounters with antigens, facilitating a rapid response upon re-exposure, essential for vaccine efficacy.

    Lymphocytes: Central Players in Adaptive Immunity

    • B Lymphocytes: Produce antibodies that act as antigen receptors, differentiating into plasma cells upon activation to secrete antibodies.
    • T Lymphocytes: Express T cell receptors (TCRs) recognizing antigens presented as peptides. They subdivide into:
      • T helper (Th) cells (CD4+): Secrete cytokines, activate dendritic cells, macrophages, and assist B cells in antibody production.
      • T cytotoxic (Tc) cells (CD8+): Target and destroy virus-infected and tumor cells.

    Antibody Classes (Isotypes) and Functions

    • Antibody heavy chains can vary while maintaining specificity through class switching, influenced by CD4 T cell interactions (CD40/CD40 ligand).
    • Each isotype has unique functional properties while retaining the same antigen-binding specificity.

    Class Switching Mechanism

    • In class-switching, a rearranged heavy-chain variable region can be connected to various Fc portions via DNA splicing, resulting in functionally distinct antibodies.

    T Regulatory Cells (Treg)

    • CD4+ CD25+ T cells responding to peptides presented on MHC class II surfaces, essential for preventing autoimmunity.

    Antigen-Presenting Cells (APCs)

    • Naïve T lymphocytes activate and obtain effector functions through interaction with peptides presented by APCs such as dendritic cells and macrophages.
    • APCs are crucial for T cell differentiation (e.g., TH1 vs. TH2) and provide necessary costimulatory signals (e.g., B7/CD28) alongside peptide-MHC recognition.

    Conclusion

    • Understanding lymphocyte mechanisms and immune responses is foundational for advancing knowledge in health and disease, and is critical for subsequent study in immunology and related fields.

    Studying That Suits You

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

    Quiz Team

    Related Documents

    Intro to Immunology - Lymphocytes PDF 2024

    Description

    This quiz covers the foundational concepts related to lymphocytes in immunology. It is based on the instruction from the 'Foundations' block, focusing on cellular and molecular medicine. Participants will deepen their understanding of the role of lymphocytes in the immune system.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser