Lecture 4 - Innate Immunity

Question 0

innate immunity recognition of microbes characteristics

Answer 0

specificity: PAMPs and DAMPs
receptors: PRRs
distribution: nonclonal (identical receptors on various cell)

Question 1

What are the 3 major types of defenses in innate immunity?

Answer 1

Inflammation, physical barriers, and anti-viral responses

Question 2

adaptive immunity recognition of microbes characteristics

Answer 2

specificity: microbial and nonmicrobial Ags
receptors: BCRs and TCRs
distribution: clonal (identical on 1 cell, diff b/w 2 cells)

Question 3

What are the 4 classes of PAMPs

Answer 3

nucleic acids, proteins, cell wall lipids, carbohydrates

Question 4

what is included in nucleic acid PAMPs

Answer 4

ssRNA, dsRNA, CpG (unmethylated, ONLY in bacteria)

Question 5

what is included in protein PAMPs?

Answer 5

Pilin, Flagelin

Question 6

What are some cell wall lipid PAMPs?

Answer 6

LPS (-), Lipoteichoic acid aka LTA (+)

Question 7

what are the carb PAMPs?

Answer 7

Mannan, Glucans

Question 8

What are the 3 types of DAMPs?

Answer 8

Stress-induced proteins, Crystals, Nuclear proteins

Question 9

What are 3 examples of DAMPs and what class do they belong to?

Answer 9

HSPs (stress proteins), Monosodium urate (crystals), HMGB1 (nuclear proteins)

Question 10

Which IL regulates rising temperature that is sensed in the brain?

Answer 10

IL-1 beta

Question 11

What are the 5 types of pattern-recognition receptors (PRR)?

Answer 11

TLR, CLR, NLR, RLR, CDS

Question 12

which TLRs are expressed on the cell surface?

Answer 12

1,2,4,5,6

Question 13

Which TLRs are expressed in endosomes?

Answer 13

3,7,8,9

TLR 7,9 utilize MyD88 pathway

Question 14

Which adapter does TLRs 1,2,5,6 use and what does it activate?

Answer 14

MyD88 activates transcription factors NF-kB and AP-1

Question 15

what adaptor does TLR3 use and what does it activate?

Answer 15

TRIF and activates TFs IRF3 and IRF7

Iverson uses himself (AI) and Pistol Pete

Question 16

TLR 1, TLR 2, TLR 6 ligand

Answer 16

bacterial lipopeptides/proteins

Question 17

TLR3 ligand

Answer 17

dsRNA

Question 18

TLR4 ligand

Answer 18

LPS

Question 19

TLR5 ligand

Answer 19

flagelin

Question 20

TLR 7, TRL 8, ligand

Answer 20

ssRNA

Question 21

TLR 9 ligand

Answer 21

unmethylated CpG DNA

Question 22

What is special about TLR 4?

Answer 22

it uses both the MyD88 and TRIF pathways

its ligand (LPS) mediates septic shock

Question 23

what does TLR Activation do?

Answer 23

triggers antimicrobial pathways that directly kill the pathogen, may cause injury to host by inducing apoptosis or septic shock

Question 24

what cytokine controls the adaptive T-cell immune response?

Answer 24

IL-12 John Stockton

Question 25

TRIF works with _____? MyD88 works with _____?

Answer 25

TRAM TIRAP

Question 26

What are NLRPs and what do they do?

Answer 26

subfamily of NLRs that respond to cytosolic PAMPs and DAMPs forming signaling complexes called inflammasomes

Question 27

what do inflammasomes activate and what is its function?

Answer 27

caspase-1 and it cleaves inactive cytoplasmic cytokines IL-1beta and IL-18 their secreted froms are proinflammatory cytokines

Question 28

what are SRs?

Answer 28

trimeric complexes of type II transmembrane proteins

Question 29

what 3 extracellular domains do they have? what family members?

Answer 29

SRCR, collagen-like, alpha-helical coiled-coil SR-A I, SR-A II (no SRCR), MARCO (no alpha helix)

Question 30

what are the MMR domains? what family members?

Answer 30

Cys N-term, fibronectin-like, C-type lectin MR, DEC-205

Question 31

what are SRs? what do they bind?

Answer 31

group of receptors mediating the uptake of oxidized lipoproteins into cells bind bacteria based on (-) charges, ie. LPS, LPA, nucleic acids, B-glucans, proteins

Question 32

what SRs are expressed on macrophages?

Answer 32

SR-A | CD36 (also a TLR2/6 recognition coreceptor)

Question 33

What do SR-KO mice exhibit?

Answer 33

increased susceptibility to infection with several pathogens

Question 34

what does the C-type lectin family cotain?

Answer 34

conserved carb recognition domain of microbial mannose, N-acetylglucosamine, and B-glcuans (bacteria)

Question 35

what are eukaryotic cell carbs often terminated by?

Answer 35

galactose and sialic acid

Question 36

what are mannose receptors involved in and what do they recognize?

Answer 36

phagocytosis terminal D-mannose, L-fucose, N-acetyl-D-glucosamine

Question 37

what do epithelial barriers provide?

Answer 37

physical barrier to infection, killing of microbes by locally produced antibiotics (defensins, cathelicidins) and intraepithelial lymphocytes

Question 38

what are defensins, who makes them, what do they do?

Answer 38

small cationic peptides with (+) and hydrophobic regions they are produced by epithelial cells and granule-containing leukocytes defensins alpha and beta produced by diff cell types have direct toxicity to microbes and kill by inserting into their membranes

Question 39

what are cathelicidins, who makes them, what do they do?

Answer 39

made by neutrophils and barrier epithelial cells in skin, GI & resp. tracts 18-kD 2 domain protein cleaved into 2 peptides (stimmed by cytokines) have direct toxicity to microorganisms

Question 40

what can neturalize LPS?

Answer 40

LL-37 of cathelicidins (plays anti-inflammatory role by binding DNA, blocks AIM2)

Question 41

what do activated macrophages produce and what do their products do?

Answer 41

IL-10 polarizes TH2 (helper T's) | IL-12 polarizes TH1 (cytotoxic T's)

Question 42

precursor Id2 transcription factor signaling of ILCs

Answer 42

IL-15 and IL-7 --> T-bet (ILC1) --> IL-12 and IL-18 --> IFN-gamma which stimulates phagocytes and TH1 response (cytotoxic T)

Question 43

what do NK cells recognize and what do they do?

Answer 43

ligands on own infected/stressed cells | release intracellular pathogens for phagocytosis

Question 44

what do NK cells activate and what are the receptors called

Answer 44

PTKs (always on) KIRs do not kill class 1 MCH expressing healthy cells phosphatases prevent activation

Question 45

when do NK cells become activated?

Answer 45

when the inhibitory receptor is not engaged | NK will kill cells not expressing MHC I molecules (virus infected/stressed)