Innate Immunity Flashcards
First line of Defence include
Physical and Biochemical Barriers and the Human Microbiome
Epithelial Cell-Derived Chemicals
Antimicrobial peptides
cathelicidins
Defensins
Collectins
GI bacteria flora functions
a) Produce enzymes that facilitate the digestion and utilization of many molecules in the human diet
b) Usable metabolites
Antibacterial factors that prevent colonization by pathogenic microorganisms
Second line Defence
Inflammation
4 characteristics of inflammation
a) Occurs in tissues with a blood supply (vascularized)
b) Rapid activation
c) Depends on cellular and chemical components
d) Nonspecific
Inflammation process (3 steps)
- Vasodilation
- Increased vascular permeability
- White blood cell adherence
4 Benefits of inflammation
§ Prevents infection and further damage by microorganisms
§ Limits and controls the inflammatory process
§ Interacts with components of the adaptive immune system to elicit a more-specific response to contaminating pathogens
§ Prepares the area of injury for healing and repair
Complement system
a) Activation of C3 and C5
3 major pathways control the activation of complement system inflammation
a) Classic pathway: activated by antibodies
b) Alternative pathway: activated by substances on the surface of bacteria
c) Lectin pathway: activated by plasma proteins that recognize carbohydrate patterns of pathogens
Classic pathway activated by
activated by antibodies
Alternative pathway activated by
activated by substances on the surface of bacteria
Lectin pathway activated by
activated by plasma proteins that recognize carbohydrate patterns of pathogens
Four functions of inflammation
a) Opsonization
b) Anaphylatoxic activity, mast cell degranulation
c) Leukocyte chemotaxis
d) Cell lysis (MAC)
3 functions Clotting system
a) Stop bleeding
b) Trap microorganisms
c) Provide framework for future repair
Kinin system
Prekallikrein–> bradyknine –>
· vessel dilation,
· prostgalndins (pain)
· Increase vascular permeability
Control and Interaction of Plasma Protein system
Mast cells
activation of inflammation