lecture 2

Question 1

key functions of innate immunity

Answer 1

1. prevent, control and eliminate infectious agents
2. recognize and eliminate products of damaged/dead host cells -> initiate tissue repair
3. stimulate and influence adaptive (special) immune repsonse

Question 2

components of innate immunity

Answer 2

mechanical barriers
chemical barriers
physiological factors
proteins
cells
initiates adaptive immune response
disruption of innate immunity by microbes :(

Question 3

mechanical barriers

Answer 3

intact skin
mucosal epithelia & mucus (sneezing, coughing, vomiting, diarrhea)
shedding of infected skins
flushing of bodily fluids (tears, saliva, sweat, pee)

Question 4

chemical barriers

Answer 4

skin (sebum - sweat)
saliva (lysozyme and antibiotics
mucus (lysozyme and antibiotics)
tears (lysozyme)
DEFENSINS (alpha, beta and gamma - within skin, mucosal epithelial cells, neutrophils and NK cells)
CATHELICIDINS (neutrophils, skin epithelia, GI/respiratory mucosa - will poke hole in pathogen mwhaha)
LACTOFERRIN (bind to iron to create stabber for microbe… decreases RBC production, acute phase protein)
HCl (in stomach)
bile salts and acids

Question 5

physiological factors

Answer 5

temperature (high fever reduces growth for microbes)
oxygen tension (high O2 makes anaerobic microbes die)
hormonal balance (corticosteroids lead to decreased inflammatory response which could lead to infection)
age (kids and gpas at higher risk to disease bc suboptimal immune systems)

Question 6

effector proteins

Answer 6

complement
mannose binding lectin
c reactive protein
cytokines (TNF, IL-1, chemokines, IFNalpha, IFNbeta, IFNg, IL12, IL15, IL10, TGFb, IL8)
natural antibodies
acute phase proteins (lactoferrins)

Question 7

complement effector protein

Answer 7

kills microbes
opsonization of microbes (through initiating phagocytosis)
activation of leukocytes (WBC)

Question 8

opsonization

Answer 8

extracellular protein that signals to phagocytizing cell to eat it and KILL, tag cells for phagocytosis

Question 9

mannose binding lectin

Answer 9

collectin
binds carbohydrates
opsonization of microbes
activation of complement -> lectin pathway

Question 10

C reactive protein

Answer 10

pentraxin
osponization of microbe
activation of complement

Question 11

TNF, INL1, chemokines

Answer 11

inflammation

Question 12

IFNa & b

Answer 12

resistance to viral infection

Question 13

IFNg

Answer 13

macrophage activation (macrophage cant kill microbe unless activated!)

Question 14

IL12

Answer 14

NK and Tcells make IFNg (macrophage activation!)

Question 15

IL15

Answer 15

proliferation of NK cells

Question 16

IL10, TGFb

Answer 16

control inflammation

Question 17

IL8

Answer 17

CXCL8 - chemokine

chemoattractant of neutrophils

Question 18

natural antibodies

Answer 18

made by B cell from fetal liver stem cells (hemopoetic)

Question 19

acute phase proteins

Answer 19

lactoferrin

inflammation

Question 20

alarmins

Answer 20

inflammatory molecule as result of damaged cell/tissue
heparan sulfate (repair ECM)
heat shock proteins (repair cytoplasm?)

Question 21

vasoactive lipids

Answer 21

inflammatory molecule as result of damaged cell/tissue
prostaglandins
leukotrienes

Question 22

generation of vasoactive lipids from cell membrane

Answer 22

damage to cell/tissue -> phospholipases activated -> cell membrane phospholipids broken -> arachidonic acid -> a. leukotriene -> b. prostaglandin
results in increased vascular permeability and smooth muscle contraction (swelling) or pain and vasodilation
5-lipoxygenase (enzyme for leukotriene)
cycloozygenase (enzyme for prostaglandin)

Question 23

aspirin inhibits

Answer 23

cyclooxygenase -> so the pain and vasodilation response of prostaglandins is inhibited

Question 24

steroids inhibit

Answer 24

phospholipase -> so the entire vasoactive lipid pathway is disrupted, no swelling or pain response

Question 25

LTB4

Answer 25

leukotriene that is involved in chemotaxis for blood leukocytes (neutrophils and eosinophils) aka triggers cell responders to come kill

Question 26

LTC, LTD, LTE

Answer 26

leukotriene that increases vascular permeability and smooth muscle contraction aka swelling

Question 27

neutrophil

Answer 27

effector cell (innate inflammatory response) early phagocytosis kills microbes 10^11 produced daily, in instance of infection there are lots of neutrophils produced

Question 28

macrophage

Answer 28

effector cell - sentinel secondary phagocytosis to finish the job of neutrophil kills microbes secretes cytokines that stimulate inflammation antigen presenting to T cell!! shows antigen after killing the pathogen which is helpful for future response)

Question 29

NK cell

Answer 29

lysis of infected cell | activates macrophage through secretion of INFg

Question 30

sentinel cell

Answer 30

sense tissue damage and recognize microbes induce inflammation (to localize the infection!) recruit blood leukocytes via cytokines and chemokines kill pathogens

Question 31

dendritic cell

Answer 31

sentinel cell most important in antigen presenting <1% of cell type in body 1. capture, process and present antigens to lymphocytes - PROFESSIONALLY - this is how primary immune response initiated 2. provide signals to stimulate T cell proliferation and differentiation 3. secrete cytokines and chemokines (attract leukocytes) langerhans interstitial DC interdigitating DC circulating DC

Question 32

mast cell

Answer 32

sentinel cell secrete: vasoactive amine (histamine & serotonin -> increase vascular permeability & pain) & inflammatory proteins (like cytokines which attract blood leukocytes)

Question 33

PAMPS

Answer 33

pathogen associated molecular patterns (for recognition done by sentinel cells) - conserved molecular motifs found ON THE microbes (their signatures) -> stimulate a specific innate immune response once bind to recognition receptor - detected by pattern recognition receptors (same receptor can bind different microbes nucleic acids: virus' and bacteria detecting proteins: bacteria cell wall lipids: gram - bacteria carbohydrates: fungi, bacteria

Question 34

pattern recognition receptor

Answer 34

can be found in: soluble (collectins, ficolins, complement, pentraxins) w/in vesicles (TLR3, 7, 8, 9) - can sense the presence of pathogen from endosome cytoplasmic (Rig1, NOD like, peptidoglycan receptors, DNA receptors - detect the pathogens PAMPS that hide in cytoplasm) membrane bound (TLR, lectin, mannose receptor, langerin, dectin, scavenger receptors, integrins - allow cell to recognize an extracellular pathogen)

Question 35

DAMPS

Answer 35

damage associated molecular patterns produced from stressed of injured host cells stress induced (heat shock protein) crystals (monosodium urate) nuclear proteins (HMGB1 - high mobility group box 1 protein - nuclear proteins that are present around the chromosome)

Question 36

PAMP-PRR binding

Answer 36

example: LPS (gram - molecular pattern) binds to TLR4 cell membrane protein to signal cytokine release DAMP disruption activates HMGB1 to trigger endothelium, neutrophil (inflammation -> tissue damage -> shock), macrophages, dendritic cells and epithelium

Question 37

EqStim

Answer 37

medication that can be used to activate sentinel cell killing mechanisms prime horses with injection prior to shipping and reduces respiratory infection same with zelnate

Question 38

innate vs adaptive

Answer 38

innate: specific for structures shared by groups of related microbes, limited diversity - sticks to germline, no memory, and in not reactive to self adaptive: specific for antigens of microbes and nonmicrobial antigens, very diverse - receptors are produced by somatic recombination of gene segments, does have memory!, not reactive to self