Lecture 1: Intro Flashcards
Advantage and disadvantage of innate system
ADVANTAGE: instantaneous activation
DISADVANTAGE: lack of specificity to target pathogens
Advantage and disadvantage of adaptive system
ADVANTAGE: memory and specificity
DISADVANTAGE: slow (over a week to become operational)
Innate system ________ of pathogen to infect host; adaptive _________ pathogen
delays ability
eliminates
Two barriers to infection (first line of defense in innate immunity)
1) Skin
2) Mucosa
Name of chemicals produced by skin to fight off pathogens
defensins
Mechanisms by which mucosa protects against invaders
1) mucus traps pathogens
2) cilia beat and eject particles out
3) tears and saliva produce hydrolytic enzymes to kill bacteria
Three classes: mechanical, chemical, microbiological
What two systems developed their own REGIONAL immune system?
gut and lung
Second line of defense in innate immunity:
group of rapidly mobile cells that can go to site of infection and kill pathogen
What are the two signals these cells respond to?
1) PAMPS (pathogen associated molecular patterns)
2) DAMPS (damage associated molecular patterns)
How, molecularly, do these innate cells recognize PAMPS and DAMPS?
Via the pattern recognition receptors (PRRs):
1) TLR: Toll-like
2) RLR
3) NLR
What functionally serves as the “on” switch for an innate immune response?
activation of TLR
What are the 2 pathways used by innate system to neutralize threat?
1) soluble proteins made in the liver (mannose binding receptor, serum proteins in the complement system)
2) immune effector cells
What are the 2 types of proteins the liver makes to support the innate system?
1) Mannose binding receptor - circulates in the plasma, binds to mannose containing structural components of bacterial cell walls. Activation of this phagocytoses bacterium
2) serum proteins known as the complement system
What is known as the ancestral precursor of the antibody?
Mannose binding receptors (identify bacteria and phagocytose it)
What are the main cells of the innate immune system?
leukocytes
What is the main hallmark of leukocytes?
granules - contain lots of killer molecules that, when released, destroy the bacteria