Non-specific Immunity-

1
Non-specific Immunity- 1st Line of Defense

• Nonspecific immunity- mechanisms of the body that
  respond to many different pathogens or invaders

2
Nonspecific Immunity

• Prevent or destroy pathogens
• Attacks anything that is considered not self-
  viruses, bacteria, prions
• Attacks pathogen immediately
• General defense

3
Mechanisms Involved

• 1. Species Resistance- genetic characteristics
  which prevent an organism from contracting a
  disease
• Ex. Dogs cannot contract mumps
• 2. Mechanical Barriers- castle wall of our body
  of densely packed cells and other materials which
  protect from invasion, sloughed off (10B skin
  cells/day250 g./year)
• Ex. Skin, mucous membranes
• If either is broken, pathogens can enter.

4
First Line of Defense

• Mechanical barrier on all surfaces of body
  exposed to external world
• What are they?
• Skin
• Mucous membranesnasal, respiratory
• Lining of mouth
• Lining of gut
• Lining of vagina/urethra
• Surface of eye

5
Barrier Membranes
Skin
6
Mechanisms Involved

• 3. Chemical Barriers- chemicals that interfere
  with the production of a pathogen
• Ex. Mucus- sticky, traps pathogen
• Enzymes- proteins that destroy pathogen
• HCl- stomach acid- lowers pH to kill pathogen
• 4. Resident microbes-have commensal or
  mutualistic bacteria and fungi that are normally
  present and out-compete potential pathogens

7
(No Transcript)
8
Second Line of Defense

• Fever
• Inflammation
• Phagocytosis
• All work tightly with specific immunity

9
Fever
Trigger not completely understood Muscular
contraction and constriction of skin blood
vessels cause core temperature to rise

• Pluses
• Inhibit microbial growth
• Enhance immune cell performance
• Speed tissue repair

• Minuses
• Malaise
• Body aches
• chills

• Breaking fever or crisis of fever
• body begins to cool by sweating,
• color returns as blood vessels in skin open
• Indicates infection is overcome

10
Inflammation

• Response to tissue damage from any source (burn,
  cut, pathogen, other??)
• 4 Cardinal Signs-
• redness- inc. blood volume
• swelling- inc. capillary permeablility Phagocytes
  migrate out of capillaries
• Heat- inc. blood from deep within body
• Pain- stimulates pain receptors

11
Phagocytosis

• Phagocytes move through blood and lymph and into
  connective tissues and engulf and destroy cells
  or pathogens
• Ex. Neutrophils and monocytes

12

• Langerhans cells in skin
• Phagocytes in blood
• Microglial cells in CNS

13
(No Transcript)
14
Links to Specific Immunity

• Phagocytosis continues to be common way to kill
  pathogenic cells in both specific and
  non-specific response
• Inflammation works to allow both specific and
  non-specific immune response to accelerate
• Fever also allows for better performance in both
  specific and non-specific function
• Specific immune response and antigen
  presentation further stimulates non-specific
  actions like phagocytosis, complement.

15
Great review of Body Defenses or Non-specific
Immunity
http//fajerpc.magnet.fsu.edu/Education/2010/2010_
INDEX.HTM