Ch 17 - Adaptive Immunity Flashcards
2 Branches of the immune System
Innate Immunity
Nonspecific responses present before exposure to an agent
2 Branches of the immune system
Adaptive Immunity
Develops after exposure to an agent & has memory
Phagocytes
The ultimate effector of immunity. Adaptive immunity uses various systems to help phagocytes perform phagocytosis
Adaptive Immunity
Adaptive Immunity
Defenses that target a specific pathogen. Acquired through infection or vaccination. Use B & T cell lymphocytes
Adaptive Immunity
Primary Response
First time the immune system combats a particular foreign substance
Adaptive Immunity
Secondary Response
Later interactions with the same foreign substance. Faster and more effective due to “immunological memory”
2 Arms of Adaptive Immunity
Humoral Immunity
Antibodies are immune facilitators. Clonal selection to activate proper B cells
2 arms of adaptive Immunity
Cell-mediated Immunity
Antigen presentation. Clonal selection to active proper T cells
Adaptive Immunity
Cytokines
Chemical messengers of immune cells
Adaptive Immunity
Antigens
Immune response triggers
Adaptive Immunity
Epitopes
Fragments of antigens
Adaptive Immunity
Immune Memory
Defining feature of adaptive immunity. Cell’s ability to remember previous pathogens.
Adaptive Immunity
Secondary Responses
very fast and very effective
Adaptive Immunity
Humoral Immunity
Fights antigens outside of host cells. Produces plasma cells that secrete protein antibodies to combat antigens.
Humoral Immunity
B Cells
Lymphocytes that are created and mature in red bone marrow. Recognize antigens with B cell receptor (BCR). Make antibodies. Named bursa of Fabricius in birds.
Humoral Immunity
B Cell Receptor (BCR)
Recognize antigens
Cell Mediated Immunity
Cell-Mediated Immunity
Fights antigens Inside of host cells. Produces cytotoxic T Lymphocytes that destroy infected cells.
Cell-Mediated Immunity
Cytotoxic T Lymphocytes
Destroy infected cells
Cell-mediated Immunity
T Cells
Lymphocytes that are created in red bone marrow and mature in the thymus.
Cell-Mediated Immunity
T Cell Receptors (TCR)
Recognize antigens
Cytokines
Cytokines
Chemical messengers of the immune system Made by T Cells. Overproduction of cytokines can lead to exaggerated immune responses (potentially fatal).
Cytokines
Interleukins
Cytokines between leukocytes
Cytokines
Chemokines
Induce migration of leukocytes
Cytokines
Interferons (IFN)
Interfere with viral infections of host cells
Cytokines
Tumor Necrosis Factor (TNF)
Involved in the inflammation of autoimmune diseases
Cytokines
Hematopoietic Cytokines
Control stem cells that develop into red and white blood cells
Humoral Immunity
Antigens
Antibody generators. Substances that cause the production of antibodies. Usually, components of invading microbes or foreign substances. Interact with epitopes or antigenic determinants on the antigen
Humoral Immunity
Components of Humoral Immunity
Antibodies, antigen-antibody binding, MHC & antigen presentation, clonal selection & expansion of B cells
Humoral Immunity
Immunoglobulins (Ig)
Secreted proteins
Humoral Immunity
Valence
The number of antigen-binding sites on an antibody
Humeral Immunity
Immunoglobulins (Ig) Shape
4 Protein chains for a Y-shape molecule. 2 identical chains and 2 heavy chains joined by disulfide bonds. Variable regions are at the end of the arms; bind epitopes. Constant region is identical for a particular Ig class.
Humeral Immunity
5 Classes of Ig
IgM, IgG, IgA, IgE, IgD
Immunoglobulins
IgM
Pentamer (5 monomers held with a J chain), 10 binding sites (valence of 10), 6% of serum antibodies, in the blood, cause clumping of cells and viruses (binding sites), first response to an infection; short-lived
Immunoglobulins
IgG
Monomer (very small), 2 binding sites (valence of 2), 80% of serum antibodies, in the blood, lymph, and intestine, cross the placenta, trigger complement, enhance phagocytosis, neutralize toxins and viruses, protect fetus
Immunoglobulins
IgA
Monomer in serum; dimer in secretions, 2-4 binding sites (valence of 2-4), 13% of serum antibodies, mucous membranes, saliva, tears, and breast milk, prevent microbial attachment to mucous membranes
Immunoglobulins
IgE
Monomer, 2 binding sites (valence of 2), .002% of serum antibodies, on mast cells, basophils, and in blood, cause the release of histamines when bound to antigen, lysis of parasitic worms
Immunoglobulins
IgD
Monomer, 2 binding sites, valence of 2, .02% of serum antibodies, structure similar to IgG, in blood, lymph, and on B Cells, no well-defined function; assists in the immune response on B Cells
Antigen-Antibody Binding
Antigen-antibody complex
forms when antibodies bind to antigens. Strength of the bond is the affinity. Protects the host by tagging cells/molecules for destruction by phagocytes and other cells
