Bio 201 Unit 10 Immunology: Antibodies & Humoral Defenses PDF

BIO 201 Unit 10 Immunology: Antibodies and Humoral Defenses Chapter 17, 18 & 19 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Trans...

BIO 201 Unit 10 Immunology: Antibodies and Humoral Defenses Chapter 17, 18 & 19 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests I. Antigens and Antibodies A. Terminology 1. Antigen: Immunogen, allergen, Ag Any substance that causes antibody formation Can be: A microbe, foreign material or “self” Usually proteins or large polysaccharides I. Antigens and Antibodies A. Terminology 2. Antibody: Immunoglobulin, Ab, Ig Protein made in response to an antigen Recognize and bind to the Ag 3. Antigen-Antibody Reaction Ab will attach to the Ag at a specific site Valence: Number of Ags that will attach to Ab I. Antigens and Antibodies Fig. 17.2 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests II. Types of Acquired Immunity A. Active: body makes own Ab How are we exposed to Ag? 1. Natural Active Come across the antigen naturally Example: Cold viruses 2. Artificial Active Antigen artificially introduced (Vaccine) Vaccines: MMR, DPT or DTaP, Hib II. Types of Acquired Immunity B. Passive: Ab from an animal/human How are we exposed to Ab? 1. Natural Passive Ab goes from mother Infant Placental or colostrum 2. Artificial Passive Ab received via injection Example: Antitoxins (antiserum) or Rhogam (anti-Rh antisera) II. Types of Acquired Immunity Fig. 19.5 II. Types of Acquired Immunity Fig. 17.18 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests III. Serum Immunoglobulins A. Serum Electrophoresis: Gamma globulin portion of serum 1. IgA= gA = Secretory Ab MW: 70,000 or 400,000 Daltons Found in: Mucous, saliva, tears, colostrum & blood 1st and 3rd lines of defense 13% of total Ab in serum but % higher in total secretions of the body Monomer in blood; dimer in secretions III. Serum Immunoglobulins A. Serum Electrophoresis: Gamma globulin portion of serum 2. IgD= gD MW: 180,000 Daltons Internal marker on B lymphocytes 0.02% of total Ab Monomer III. Serum Immunoglobulins A. Serum Electrophoresis: Gamma globulin portion of serum 3. IgE= gE = Allergic Ab MW: 200,000 Daltons Involved in hypersensitivity or allergic reactions 0.002% of total Ab Monomer III. Serum Immunoglobulins A. Serum Electrophoresis: Gamma globulin portion of serum 4. IgG= gG = Circulatory Ab MW: 160,000 Daltons Protects against microbes, triggers complement, and increases phagocytosis Crosses fetal-placental membrane 80% of total Ab Monomer III. Serum Immunoglobulins A. Serum Electrophoresis: Gamma globulin portion of serum 5. IgM= gM = Circulatory Ab MW: 900,000 Daltons 1st Ab to arrive in response to initial exposure to Ag Short lived Does NOT cross: Fetal-placental membrane 6% of total Ab Pentamer III. Serum Immunoglobulins Table 17.2 III. Serum Immunoglobulins B. Antibody Memory: Anamnestic Response Titer: unit of antibody level Initial: 4-7 days IgM; 10-17 days IgG Secondary: 2-7 days IgG with a greater magnitude Fig. 17.17 III. Serum Immunoglobulins C. Antibody Structure Fig. 17.4 III. Serum Immunoglobulins C. Antibody Structure of a Monomer 4 polypeptide chains: 2 heavy & 2 light Joined by disulfide bonds to form a Y shape Arms of Y: Fab region(Fragment of Ag Binding) Region where Ag binds Contains variable amino acid sequence Specific for Ag Stem of Y: Fc region(Fragment of Cell Binding) Contains constant amino acid sequence Binds to: Cells, proteins or complement Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests IV. Development of the Immunological System A. T Cells and Cellular Immunity Produced by: Stem cells in red bone marrow Mature in: Thymus Make up ~65% of total lymphocytes Responds to Ags and Fig. 17.1 results in the formation of certain subsets of T cells to be produced. Secrete cytokines: chemical messengers IV. Development of the Immunological System A. T Cells and Cellular Immunity 1. Types of T Cells a. T Helper Cells =TH= CD4 Cells Activate B cells to make Ab and macrophages Secrete: Cytokines b. Regulatory T Cells=Suppressor=CD8 Cells Suppress: Other T cells IV. Development of the Immunological System A. T Cells and Cellular Immunity 1. Types of T Cells c. Cytotoxic Cells=TC=CD8 Cells Recognize and kill target cells, “non-self” or hijacked cells, tumor cells and transplanted foreign tissue Programmed cell death: Apoptosis IV. Development of the Immunological System A. T Cells and Cellular Immunity 2. Cytokines Chemical messengers of immune cells Also known as: Interleukins, interferon, tumor necrosis factor (TNF) More than 200 types Function: Attract macrophages, protect against viral infections, toxic to tumor cells, increase Ab production IV. Development of the Immunological System B. B Cells and Humoral Immunity Produced by: Stem cells & mature in red bone marrow Named for Bursa of Fabricius (Chicken’s GI-lymphoid tissue) Fig. 17.1 Makes up ~35% of total lymphocytes IV. Development of the Immunological System B. B Cells and Humoral Immunity Carry “old” immunoglobulins (IgD or M) on surface. When they recognize an Ag, the B cell is activated with the assistance of TH cells to produce: 1. Memory Cells 2. Plasma Cells: These cells produce the “new” needed Abs IV. Development of the Immunological System B. B Cells and Humoral Immunity Fig. 17.5 IV. Development of the Immunological System C. Dual Nature of Immunity: cells & antibodies Cellular-T cells and Humoral-antibodies Fig. 17.19 IV. Development of the Immunological System D. Results of Antigen & Antibody Binding 1. When Ab encounters specific Ag it forms an: Ag-Ab complex forms 2. Ab molecule is not damaging to Ag but it triggers mechanisms that are damaging. IV. Development of the Immunological System D. Results of Antigen & Antibody Binding 3. Types of Mechanisms: Agglutination: Reduces # of microbes Opsonization: Enhances phagocytosis Neutralization: Blocks viral attachment & neutralizes toxins Complement Activation: Serum protein that causes inflammation & cell lysis IV. Development of the Immunological System D. Results of Antigen & Antibody Binding Fig. 17.8 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests V. Immunological Disorders A. Types 1. Congenital Immunodeficiency SCID: Severe Combined Immunodeficiency Rare-affects 1 in 100,000 Deficiency in both T and B cells: No Abs “Boy in the Bubble” How treated? Gene therapy V. Immunological Disorders A. Types 1. Congenital Immunodeficiency Bruton’s Disease-rare (1 out of 200,000) Decrease # of B cells: Less Ab More prone to infections DiGeorge Syndrome Defective thymus: Less T cells More prone to infections V. Immunological Disorders A. Types 2. Autoimmune Diseases: Ab against “self” Over 80 different types-75% in women (?) Affect ~10% of population in developed countries Rheumatoid Arthritis (RA): Anti-gammaglobulin Abs Systemic Lupus Erythematosus (SLE): Anti-DNA Abs V. Immunological Disorders A. Types 3. AIDS-Acquired Immunodeficiency Syndrome HIV attaches to CD4 receptors on TH cells Decreased number of: TH cells Normal level of B cells: Decreased amount of Abs Fig. 19.15 B cells not “turned on” because of lack of TH cells Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation-pgs. 538-541 A. Types: Autograft, isograft, xenograft or heterograft, homograft or allograft B. Graft Acceptance and Rejection: Histocompatibility HLA: Human Leukocyte Antigen Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests VII. Allergic Disorders: Hypersensitivity A. Immediate or Antibody Mediated 1. Type I: Anaphylactic Reaction 2. Type II: Cytotoxic Reaction 3. Type III: Immune Complex Reaction B. Delayed or Cell Mediated 4. Type IV: Delayed Type Reaction VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated 1. Type I: Anaphylactic Reaction Examples: Insect stings, drug or food allergies, hay fever, allergic asthma Time Interval: 2-30 minutes Sensitizing Dose: 1st exposure to allergen Produces IgE: Fab recognizes allergen and Fc attaches to basophils or mast cells VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated 1. Type I: Anaphylactic Reaction Shocking Dose: 2nd exposure Basophils or mast cells: histamine gastric, lacrimal, & nasal secretions vascular permeability BP resulting in: Anaphylactic shock Localized anaphylaxis-hives, itchy, reddening VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated Fig. 19.1 VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated 1. Type I: Anaphylactic Reaction Treatment: Anti-histamine or epinephrine (Constricts blood vessels/increases BP) Lab Tests: Skin tests, eosinophilia, IgE (RAST) Fig. 19.3 VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated 2. Type II: Cytotoxic Reaction Examples: Transfusion blood reactions & hemolytic disease of the newborn (HDN) Time Interval: 5 – 12 hours Body exposed to Ag & makes IgG or IgM Abs Abs bind with Ag and attach to target cells (rbc, wbc, platelets) Complement activated & cytolysis occurs VII. Allergic Disorders: Hypersensitivity A. Immediate or Ab Mediated 3. Type III: Immune Complex Reaction Examples: Post-streptococcal Glomerulonephritis & Rheumatic Fever Sequelae infection: Secondary consequence Time Interval: 3 – 8 hours Body exposed to Ag; makes IgG or IgM Ab; Ab binds with Ag; forms Ab-Ag Immune Complex (IC) IC’s: Very large, deposited on blood vessel walls, penetrate walls to cause inflammation VII. Allergic Disorders: Hypersensitivity B. Delayed or Cell Mediated 4. Type IV: Delayed Type Hypersensitivity Reaction Examples: TB Tine Skin Test, some drug allergies, poison ivy Time Interval: 2-3 days (delay due to time for T cells & macrophages to migrate to Ag) No Ab involvement; caused by T cells VII. Allergic Disorders: Hypersensitivity B. Delayed or Cell Mediated 4. Type IV: Delayed Type Hypersensitivity Reaction Ag enters body & attaches to target tissue (skin) T cells react with Ag to destroy Ag but it also destroys target tissue: Dermatitis Fig. 19.9 VII. Allergic Disorders: Hypersensitivity B. Delayed or Cell Mediated 4. Type IV: Delayed Type Hypersensitivity Reaction Fig. 19.8 Table 19.1 Overview I. Antigens and Antibodies II. Types of Acquired Immunity III. Serum Immunoglobulins IV. Development of the Immunological System V. Immunological Disorders VI. Tissue Transplantation VII. Allergic Disorders (Hypersensitivity) VIII. Immunological Tests 1. Direct: Detection of Ag (Direct Strep throat testing) Specimens will vary 2. Indirect: Detection of Ab (HIV testing) Specimens: Serum