Immune System

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Immune System
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Immune System

• Bodys defense against disease-causing organisms
  (pathogens)

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Immune System

• First line of defense
• Barriers that keep pathogens from entering the
  body
• Skin
• Hair and mucus in nose
• Sneezing and coughing
• Saliva
• Stomach acids

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Immune System

• Second line of defense
• General defense when body cells are damaged
• Inflammatory responsefluid and white blood cells
  leak from blood vessels into surrounding tissue

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Immune System

• Second line of defense
• General defense when body cells are damaged
• Inflammatory responsefluid and white blood cells
  leak from blood vessels into surrounding tissue
• White blood cells
• attack invaders and eat
• them
• Phagocytewhite
• blood cells that engulf
• pathogens and destroy
• them by breaking
• them down

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Immune System

• Second line of defense
• General defense when body cells are damaged
• Inflammatory responsefluid and white blood cells
  leak from blood vessels into surrounding tissue
• Interferonssubstances produced by body cells
  when they are attacked by viruses
• Interfere with the production of new viruses

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Immune System

• Third line of defense
• Immune response distinguishes between different
  kinds of pathogens
• Macrophageswhite blood cells that patrol the
  body looking
• for invaders
• They send
• off chemical
• signals to
• helper
• T-cells

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Immune System

• Third line of defense
• Immune response
• Helper T-cells have many
• jobs
• Make macrophages better able to kill
• Call other cells in the immune system to the
  battle
• This causes fever, swelling and aches
• Signs that your body is working to fight a
  disease
• Send chemicals that increase production of
  B-cells
• Signal killer T-cells where the invader is hiding

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Immune System

• Third line of defense
• Immune response
• B-cells produce antibodies
• Proteins produced by the immune system which
  destroy certain kinds of pathogens
• Antigenthe
• part of the
• pathogen that
• the antibody
• recognizes and
• binds to

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Preventing Disease

• No cure for viral disease
• Prevention is the key
• Vaccinemade from damaged particles that cant
  cause disease anymore

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Preventing Disease

• First Vaccine
• 1798Dr. Edward Jenner
• Developed a vaccine for smallpox from the cowpox
  virus

The arm of Sarah Nelmes, a dairy maid, who had
contracted cowpox. Jenner used material from her
arm to vaccinate an eight year old boy, James
Phipps (1798).