Ch 34 34.4-34.10

1
Ch 34 34.4-34.10

• Immunity

2
Characteristics of Vertebrate immunity

• B T lymphocytes distinguish self from non-
  self
• ignore normal body cells and attack pathogens or
  altered body cells.
• BT mount attack AFTER they have been sensitized
  to a specific threat.
• BT show great diversity to the things they can
  act against
• BT have a Memory some of the BT cells that
  form the first time they encounter a pathogen are
  set aside for future encounters.

3
Antigens

• Anything that triggers the production BT cells
  and becomes a target of their attack is an
  ANTIGEN.
• When an antigen triggers the production of BT
  cells some will become
• 1- effector cells- these act at once- this is the
  primary response
• 2- memory cells- these enter a resting phase but
  all have receptors for that specific antigen
  and are ready for a faster secondary response
  if the antigen shows up again.

4
Antibodies

• Effector B cells are the only ones that can
  secrete antibodies- a molecule that binds to
  certain antigens, other WBCs attack any molecule
  that has antibodies attached to it. Antibodies
  also inactivate antigen bearing cells in the
  blood and other body fluids and promote
  inflamation.

5
Cytotoxic T Cells

• These carry out cell mediated response to
  pathogens. That means that attack body cells that
  have pathogens inside them for example a virus.
  These are also the cells that recognize and kill
  cancer cells. They are also the cells that attack
  transplanted organs.

6
Immunotherapy

• Medical attempt to boost the immune system (
  Cancer patients undergoing radiation or chemo)
• Hematopoietic growth factors- stimulate
  production of blood cells in bone marrow.
• Cytokines stimulate production of defense cells
  ( BT)
• Cancer Vaccines ??? Prime the body to recognize
  and fight cancer cells ( malignant melanoma)

7
Sec. 34.9

• Immunization process that promotes immunity.
• Active Immunization- a antigen containing
  vaccine introduces a weakened or dead copy of
  pathogen Causes Primary Immune response
  booster shot causes secondary response.
• Passive immunization- injection of antibodies
  purified from the blood of someone who has
  survived disease. The antibodies fight the
  infection but dont cause an immune response.

8
Allergies

• A substance that is normally harmless provokes
  and immune response. Antihistamines treat
  symptoms and desensitization programs can help
  end symptoms.
• Anaphylactic shock- life threatening allergic
  response to an allergen. Fluids leak out of
  capillaries and BP drops.

9
Autoimmune Disorders

• Occur when self recognition fails and immune
  fighters attack ones own body cells. More
  frequent in women.
• ex.- Graves Disease, rheumatoid arthritis,
  multiple sclerosis.
• Deficient immune response- loss of immune
  response, Primary Im. Deficiency present at
  birth. Secondary Im. Deficiency results after
  exposure to an outside agent such as a virus
• ex. AIDS.