Study Guide - Immune System.pdf

Study Guide Immune System A. Compare the functions of innate immunity vs. adaptive immunity 1. Innate immunity i. Innate immunity is non-specific to a given pathogen (a) Eliminate pathogen rap...

Study Guide Immune System A. Compare the functions of innate immunity vs. adaptive immunity 1. Innate immunity i. Innate immunity is non-specific to a given pathogen (a) Eliminate pathogen rapidly (b) Mediate initiation and development of adaptive immunity (c) Work with adaptive immune response to eliminate pathogen 2. Adaptive immunity i. Specific to different pathogens, and develops a “memory” to fight them in the future (a) Specific response to a given pathogen (a) Pre-activation required (i) Days to weeks (b) Re-activated if a high enough threat is sustained (activation threshold) (b) Continually develops throughout life B. Name the key components of innate immunity (Table 7-2) 1. Exterior defenses i. Epithelial barriers ii. Mucosa iii. Secretions 2. Cellular components / Phagocytes (leukocytes) i. Natural killer cells ii. Neutrophils iii. Monocytes/Macrophages iv. Neutrophils, Eosinophils, Basophils v. Mast Cells and platelets 3. Soluble mediators i. Complement (a) A system of proteins which induces the acute inflammatory response (b) Damage microbial membranes to kill cells and aid in phagocytosis ii. Cytokines (a) Proteins/glycoproteins which modify cellular behavior C. Describe the key types of cytokines 1. Chemokines i. Small cytokines that cause chemically-induced migration of leukocytes to enhance inflammation (a) Increase vascular permeability (b) Activate vascular epithelial tissue (c) Change blood flow 2. Interferons i. Produced by cells infected with viruses ii. Increase resistance to viral replication 3. Acute phase proteins  i. Pro-inflammatory cytokines which promote a variety of effects (a) Altered metabolism (b) Altered blood flow (c) Production of other proteins D. Describe the two key components of adaptive immunity 1. Humoral immunity 2. Cell-mediated immunity E. Differentiate between antigen and immunogen 1. Antigen - Any molecule which binds to an antibody or T-cell receptor 2. Immunogen – An antigen which provokes an immune system response i. Example – Adjuvant – immunostimulatory substance meant to increase response to a vaccine F. Differentiate between active and passive immunity 1. Active immunity = protection following exposure to a given antigen, providing a long-lasting protection i. Natural immunity (a) Example – exposure to influenza virus from somebody coughing ii. Artificial immunity (a) Example – exposure to influenza virus antigens from a vaccine (b) Prepares immune system to quickly produce a specific-immune response at a later time 2. Passive Immunity = antibodies or sensitized lymphocytes from an immune individual are transferred to a non-immune individual i. Produces a temporary response ii. Examples (a) Natural – Transplacental transfer of antibodies (b) Artificial – Inoculation of antibody G. Briefly describe the structure and function of an antibody 1. Produced by B lymphocytes 2. Has two sites key regions i. Fragment antigen binding site (a) binds to antigens (b) Has variable regions which allow for antigen specificity ii. Constant regions H. Briefly describe the roles of each of the five major immunoglobulin (Ig) classes 1. IgM i. first antibody in immune response ii. activates complement 2. IgG i. major antibacterial and antiviral antibody in blood ii. activated by second immune response (a) long-lasting immunity iii. passed through placenta 3. IgA i. Predominant on mucus membranes  ii. Found in various bodily secretions (a) Prevents adherence of pathogens to mucosal surfaces 4. IgE i. Found on mast cells and basophils ii. Responsive to parasites iii. Associated with allergic reactions 5. IgD i. Antigen receptor on mature naïve B cells I. Describe the clinical relevance of cell-mediated immunity 1. Protection from intracellular pathogens 2. Part of: i. Tissue transplant rejections ii. Some autoimmune diseases J. Describe the process of cell mediated immunity 1. Macrophages and dendritic cells phagocytose antigens 2. Then travel to lymph nodes 3. Present antigens to T-cells 4. If antigen matches T-cell receptor (TCR) it can become activated 5. If activated the T-cell replicates - “Clonal expansion” i. Destruction of pathogen in lymph node ii. Travel throughout body to attack pathogen iii. Activation of B cells and other cells important to immune response (e.g. macrophages) iv. Memory T-cells formed (a) Effective for rapid response to second exposure K. Describe the formation of T-lymphocytes 1. Cells from bone marrow enter the thymus to mature i. T-cell receptors formed ii. Cells that recognize “self” are destroyed (a) If this fails, autoimmune disease results 2. After maturation, they exit thymus to go to secondary lymphoid tissue (lymph nodes, spleen) L. Describe the formation/maturation of B-lymphocytes 1. Exit bone marrow i. Express IgM and IgD 2. Upon antigen activation, B-cells divide 3. Produce antibodies i. Secreted 4. Eventually mature to: i. plasma cells ii. Memory B Cells (a) Upon reactivation, generate a secondary antibody response M. Order the five phases of the immune response 1. Recognition 2. Amplification 3. Effector  4. Termination 5. Memory N. Differentiate between primary and secondary immunodeficiency 1. Primary – Deficit of T-cells, B-cells or lymphoid tissue i. Congenital 2. Secondary – Underlying diseases which depresses or blocks immune response O. Name five sources of iatrogenic immunodeficiency 1. Cytotoxic drugs 2. Corticosteroids 3. Immunosuppressive drugs 4. Radiation therapy 5. Splenectomy