Lecture 11 Innate Immunity Flashcards
What is the most abundand WBC, most active and potent phagocytic killer
Neutrophils
What is the primary function of neutrophils?
Rapid response, move into area and eliminate invaders
Neutrophils are most critical in what stages of inflammations?
early
neutrophils are the first to be recruited from _______ to _______
Bloodstream to site of damage
neutrophils are more powerful than _______
macrophages
when do neutrophils die?
once an assault on microbe is made
neutrophils kill microbes via phagocytosis and release of _______
granule content
Granular contents are
lysozyme, defensins, myeloperoxidase
neutrophiles can release DNA to form what?
neutrophile extracellular traps (NETs) catching microbes, allowing enzymes and pepetides from granules to destroy them
What is the purpose of inflammation
contain site of damage, localize response, eliminate invader, restore tissue function
What does inflammation result in
swelling, redness, heat, pain, sometimes loss of function
What triggers inflammation
Pattern recognition receptors
What do PRRs do?
detect MAMPS and DAMPS
What are MAMPs and DAMPs?
microbe associated
damage associated molecular patterns
Host cells release _______ during inflammation
Inflammatory mediators (cytokines, histamine)
MAMPS cause release of what
tumor necrosis factor
TNF does what?
induces liver to produce acute phase proteins that activate complement
blood vessel damage starts two enzymatic cascades which lead to
coagulation and increased vessel permeability
what happens to small blood vessels during inflammation
they dilate
greater blood flow, slower flow rate
leakage of fluids
What happens to leukocytes during inflammation/
migrate from bloodstream to tissues
what is margination
endothelial cells grab phagocytes and slow them down
What is diapedesis
phagocytes squeeze between cells of vessel
What do clotting factors do
wall off infection site, prevent bleeding, stop spread of microbes
What is acute inflammation
short term, mainly neutrophils, macrophages clean up damage by ingesting dead cells and debris
if acute inflammation fails, what happens?
chronic inflammation
When inflammation happens, prevents spread but _______ builds
damage
What is necrosis
traumatic cell death due to damage
what is apoptosis
programmed cell death, does not trigger inflammatory response
What is pyropoptosis
triggers an inflammatory response that sacrifices infected cells
Fever is an indicator of what type of infection
bacterial
Temperature raises due to response to ______
pyrogens
what temp is a fever
above 37.8
What happens to bacteria above 37 degrees?
drops sharply, allows more time for defense
What happens to enzymes when temperature rises
increases rate of enzymes
What do first-line defenses do
barriers that block entry
Sentinel cells use________ receptors to idenfity unique microbial ocmponents
patten recognition systems
________ system found in blood and tissue fluid
complement
________ secreted with viral infection
Interferon
________ engulf microbes or cell debris
phagocytes
What are the first line defenses
Skin, mucous membranes of digestive tract, respiratory tract, urogenital tract
Epidermis is filled with ________
keratin
________ degrade peptidoglycan
lysozyme
________ form antimicrobials, consume hydrogen peroxide to create more reactive forms of O2
peroxidases
________ and ________ bind iron
Lactoferrin, transferrin
________ form pores in microbial membranes
Defensins
Normal microbioate produces ________
toxic compounds
What is the formation and development of immune system called
Hematopoiesis
blood cells originate from ________ cells
Hematopoiesis stem cells