Chapter 24: The Body's Defenses
Farabee,  Kimball,  alternate,  good pages & quizzes,  Wiki: immune & lymphatic systems

A. Biology and Society:  2e: The Next Pandemic
  1. 1e AIDS was discovered in NY, in 1981, in healthy young men with rare diseases. 
    2. HIV destroys CD4+ T lymphocytes, essential for specific immunity,   more,  resource, all aspects,
     
  2. fig. 2 overviews ch 24.  Note the three lines of defense
B. Nonspecific Defenses
        First Line: Barriers: skin, mucous membranes & secretions: old link:
        mucus, sweat, stomach HCl, oil (hairs), immunoglobulins, lysozymes
  1. Second line: fig 2, 4, Internal Defenses = Innate Immunity
  2. uses white blood cells (except B & most T lymphocytes), proteins & inflammation,
    3. Bone marrow contains several types of stem cells, including the source of all blood cells
  3. & equivalent tissue cells & proteins in blood: interferon & complement
  4. lymph is formed in most tissues, because of capillary blood pressure
  5. so the lymphatic system (scroll to fig) drains tissues, fig 7, & lymph is filtered at lymph nodes,
  6. lymphatic system organs mature lymphocytes, fig 9, & store blood cells.
  7. If the flow is blocked or removed = edema, elephantiasis & cause
  1. These protect us from organisms & chemicals that invade & disrupt homeostasis fig. 2.
  2. Components:  WBC except B & T lymphocytes,  pictures,  NK cells,  interferon fig. 5, & complement
  3. The WBC are studied in Lab this week
  4. The inflammatory response to tissue injury, fig. 6, includes rubor, calor, tumor & dolor.
  5. Chemicals released by damaged cells & tissues cause inflammation:
  6. histamine: vasodilation & increased capillary permeability
  7. prostaglandins (& asprin), 2 & pyrogens.
         Blood coagulation: an enzyme cascade, uses plasma proteins, fibrinogen & platelets make the clot.

C. Third Line: Specific Immunity = Adaptive Immunity, can use links
  1. Antigen (Ag) is foreign, bit of a larger molecule, usually a protein, stimulates specific immune response
  2. Antibody (Ab) = Immunoglobulin (Ig), fig. 10, attacks the Ag.
  3. B & T lymphocytes have Ag receptors are like Ig,  Ag & Ab fit together,  Pregnancy test
  4. Fig 8 describes Active Immunity, Passive immunity is e.g. in breast milk, how else?
  5. B & T cells are formed in bone marrow, B cells mature there, T cells mature in the thymus: fig. 9. 
  6. B cells produce antibody = fig. 11,
  7. T cells also clone, then directly attack cells that have the antigen, fig. 14. 
  8. Big issue is in fig. 12 & 13, antigen presentation  by  "Self protein" = class I & II histocompatibility molecules
  9. T cell = cell mediated immunity
  10. The shape of the antibody base determines its function: fig. 10,  five classes of Ab,  
  11. Ab.Ag actions include clumping (blood typing), & complement activation = animation on CD
  12. Clonal selection increases the nuber of B or T-cells.
  13. Explain how effector cells and monoclonal antibodies are produced.
  14. The primary immune response is slow & weak, the secondary response is faster & stronger.
  15. Helper T cells stimulate both B & T cell responses. 
  16. Cytotoxic T cells destroy infected host cells or pathogens: fig 12, 13, 14.
REVIEW: p 532 & 538
1. What makes the first & second lines of defense non-specific?
2. What are phagocytes? Name two kinds of phagocyctes
3. Name the symptoms of the inflammatory response
4. What are the two functions of the lymphatic system?

1. What is the immune system? What is its function?
2. What is an antigen? Name some examples
3. What are the two main types of lymphocytes?
4. How does the body produce enough B cells to fight off an infection?
5. What makes a secondary immune response faster than a primary immune response?
6. What are the two main types of T cells & what does each do?
  
D. Immune Disorders: Wiki, 
  1. Allergies: fig 15, two steps, fig 15, 1) sensitization, 2) later exposure 
    2. Four types:
    1) immediate hypersensitivity, fig 15, hay fever, hives & asthma
    2) antibody mediated cytotoxicity: hemolytic disease (Rh) in newborn & myaesthenia gravis
    3) immune complex disorders: serum sickness & lupus (SLE)
    4) cell mediated hypersensitivities: Type I diabetes, multiple sclerosis, rheumatoid arthritis
  2. Anaphylactic shock - overreaction includes very low blood pressure.
    3. Epinephrine injection - QCP ex - is treatment - reduces histamine's effects  pollen count,  org,  another..
  1. Your immune system distinguishes self from non-self by MHC: everyone is unique
    2. Autoimmune diseases occur when B/T cells identify self as foreign, instructor
  2. Immunodeficiency diseases occur when something in the system is not working
  3. Three examples:  inborn,  WBC cancers,  drugs,  radiation, 
  4. HIV and AIDS are widespread.  Acquired immune deficiency syndrome described above
  5. Explain why most people with AIDS die from another infectious agent or from cancer. HIV test
E. Evolution Connection: The Yearly Battle with the Flu
  1. We can't eradicate the influenza virus like smallpox > RNA virus rapidly mutates.
  2. The historical impact of the influenza virus on humans > epidemics.  
  3. Causes of emergent diseases.