Lecture 23 (Evasion of the Immune Response by Pathogens)

Question 1

bacteria can interfere with TLR signaling pathways in many different ways and at many different positions. this can include redirecting the signaling pathways from ______________ to ________________ pathways

Answer 1

pro-inflammatory to anti-inflammatory

Question 2

__________ is a protein complex that controls transcription of DNA, cytokine production, and cell survival

Answer 2

NF-kB

Question 3

IL-10

a) pro-inflammatory cytokine
b) anti-inflammatory cytokine

Answer 3

b) anti-inflammatory cytokine

Question 4

IL-1, IL-6, TNFα

a) pro-inflammatory cytokines
b) anti-inflammatory cytokines

Answer 4

a) pro-inflammatory cytokines

Question 5

Brucella synthesizes a protein called ________ that closely resembles the mammalian Toll/IL-1 receptor

Answer 5

TcpB

Question 6

Brucella synthesizes a protein called TcpB. as a result, it causes accelerated ______________ of an adaptor protein and blocks the _______ signaling pathway

Answer 6

degradation; TLR

Question 7

a mitogen-activated protein kinase is a type of protein kinase that is specific to the amino acids ___________ and _________

Answer 7

serine and threonine

Question 8

____________ are involved in directing cellular responses to a diverse array of stimuli, such as mitogens, osmotic stress, heat shock, and pro-inflammatory cytokines

Answer 8

MAPKs

Question 9

impairs the regulation
a) P. aeruginosa
b) B. anthracis
c) Shigella spp.
d) Yersinia spp.

Answer 9

a) P. aeruginosa

Question 10

proteolysis of MKK
a) P. aeruginosa
b) B. anthracis
c) Shigella spp.
d) Yersinia spp

Answer 10

b) B. anthracis

Question 11

elimination of MAPK
a) P. aeruginosa
b) B. anthracis
c) Shigella spp.
d) Yersinia spp.

Answer 11

c) Shigella spp.

Question 12

acetylation of MAPK
a) P. aeruginosa
b) B. anthracis
c) Shigella spp.
d) Yersinia spp.

Answer 12

d) Yersinia spp.

Question 13

misdirection of signaling pathways occurs when products from Candida, Yersinia, or Mycobacteria trigger signaling through TLR2, leading to production of ____________

Answer 13

IL-10

Question 14

Staphylokinase from S. aureus can bind and…
a) neutralize defensins
b) destroy cathelicidins
c) decrease defensin activity d) block β-defensin expression by airway epithelial cells

Answer 14

a) neutralize defensins

Question 15

Staphylococcal enzyme aureolysin…

a) neutralizes defensins
b) destroys cathelicidins
c) decreases defensin activity
d) blocks β-defensin expression by airway epithelial cell

Answer 15

b) destroys cathelicidins

Question 16

Salmonella can bind and….

a) neutralize defensins
b) destroy cathelicidins
c) decrease defensin activity d) block β-defensin expression by airway epithelial cells

Answer 16

c) decrease defensin activity

Question 17

Klebsiella pneumoniae capsular polysaccharide…
a) neutralizes defensins
b) destroys cathelicidins
c) decreases defensin activity
d) blocks β-defensin expression by airway epithelial cells

Answer 17

d) blocks β-defensin expression by airway epithelial cells

Question 18

S. aureus inhibits phagocytosis by expressing ______________, which binds to Fc portion of IgG, so it prevents antibodies to bind to the Fc receptor on phagocytic cells or activating the classical complement pathway

Answer 18

Protein A

Question 19

encapsulated bacteria such as Pneumococci possess a thick ______________ capsule that phagocytes find difficult to bind

Answer 19

hydrophilic

Question 20

Streptococci produce M protein which can bind ___________ and masks C3b-binding sites

Answer 20

fibrinogen

Question 21

M protein also binds factor H, inactivating bound _______

Answer 21

C3b

Question 22

several gram-negative bacteria of veterinary importance, such as Mannheimia hemolytica and Fusobacterium necrophorum, secrete _____________ that kill leukocytes, especially granulocytes

Answer 22

leukotoxins

Question 23

the most important leukotoxins are the ___________ proteins

Answer 23

RTX (“repeats in toxin”)

Question 24

M. hemolytica secretes a __________ toxin that kills ruminant neutrophils, alveolar macrophages, and lymphocytes

Answer 24

RTX

Question 25

gram-negative bacteria such as Salmonella, Pseudomonas species, and E. coli have developed an elaborate needle complex -- a _________ ___ _____________ system -- to convey effector molecules directly into the cytosol of the effector cells

Answer 25

type III secretion system

Question 26

L. monocytogenes is taken up by induced phagocytosis, which is thought to be mediated by a membrane associated protein called ________________

Answer 26

internalin

Question 27

_____________ ___________ is an important mechanism used by pathogenic microorganisms for escaping the neutralizing activities of antibodies

Answer 27

antigenic variation

Question 28

the "relapses" of relapsing fever caused by spirochete, __________ ___________, are a result of antigenic variation by the organism

Answer 28

Borrelia recurrentis

Question 29

________ viruses have a small genome, so they don't have room to accommodate genes dedicated to suppressing immunity

Answer 29

RNA

Question 30

RNA virus proteins are multifunctional and they tend to rely on __________ _________ for immune evasion

Answer 30

antigenic variation

Question 31

_____ viruses have a larger genome and can afford to devote many different genes to immune evasion

Answer 31

DNA

Question 32

in larger DNA viruses, up to half of the total genome may be devoted to ___________________ genes

Answer 32

immunoregulatory

Question 33

some viruses (human Hepatitis C) block the effect of _________ by making soluble receptors of interferons or by blocking the activities of IL-12 and IL-18

Answer 33

IFNγ

Question 34

some viruses make their own version of cytokines and chemokines, these are called ___________ or __________ // these interfere with the normal functioning of host cytokines

Answer 34

virokines or immunoevasins

Question 35

immunoevasins are produced by viruses that interfere with the processing of antigens that bind to [MHC I/MHC II] class molecules

Answer 35

MHC I

Question 36

viruses down regulate MHC class I expression to escape detection by T cells, but they still can be detected by _______ cells

Answer 36

NK cells

Question 37

gradual change in the antigenicity of a virus as a result of mutations and selection a) antigenic drift b) antigenic shift

Answer 37

a) antigenic drift

Question 38

a sudden, major genetic change in which a new strain develops as a result of recombination between two virus strains a) antigenic drift b) antigenic shift

Answer 38

b) antigenic shift

Question 39

examples of viruses that infect lymphocytes and either kill them or impair their ability to function normally

Answer 39

-HIV -FIV -canine distemper virus -feline leukemia virus

Question 40

a state of reversible nonproductive infection is called _________

Answer 40

latency

Question 41

latency is a consistent feature of what virus?

Answer 41

herpesviruses

Question 42

t/f: during latency, a small number of viral genes are expressed and are not detected by the immune system

Answer 42

true

Question 43

M. hemolytica and BHV-1 acting together, cause severe respiratory disease in ___________

Answer 43

cattle

Question 44

BHV-1 infection [decreases/increases] expression of an integrin on lung neutrophils

Answer 44

increases

Question 45

what do immunoevasins/virokines do? a) down regulate MHC I expression b) allow for possible new host compatibility c) interfere in host cytokines causing suppression of the immune response

Answer 45

c) interfere in host cytokines causing suppression of the immune response

Question 46

match the example pathogen with how it interferes with the TLR signaling pathway: Leptospira a) modify PAMPs to not be recognized b) accelerate destruction of intermediate signals via TcpB c) destroy MAPK so transcription factors never turned on d) redirects cytokines synthesis to IL-10 rather than inflammatory

Answer 46

a) modify PAMPs to not be recognized

Question 47

match the example pathogen with how it interferes with the TLR signaling pathway: Brucella a) modify PAMPs to not be recognized b) Accelerate destruction of intermediate signals via TcpB c) Destroy MAPK so transcription factors never turned on D) Redirects cytokines synthesis to IL-10 rather than inflammatory

Answer 47

b) Accelerate destruction of intermediate signals via TcpB

Question 48

match the example pathogen with how it interferes with the TLR signaling pathway: Shigella spp. and Yersina spp. a) modify PAMPs to not be recognized b) Accelerate destruction of intermediate signals via TcpB c) Destroy MAPK so transcription factors never turned on D) Redirects cytokines synthesis to IL-10 rather than inflammatory

Answer 48

c) Destroy MAPK so transcription factors never turned on

Question 49

match the example pathogen with how it interferes with the TLR signaling pathway: Candida sp, Yersina sp. and Mycobacteria sp. a) modify PAMPs to not be recognized b) accelerate destruction of intermediate signals via TcpB c) destroy MAPK so transcription factors never turned on d) redirects cytokines synthesis to IL-10 rather than inflammatory

Answer 49

d) redirects cytokines synthesis to IL-10 rather than inflammatory

Question 50

what mechanism to avoid being phagocytosed is utilized by: Staph aureaus a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 50

a) Protein A, which competitively binds the Fc portion of Ab

Question 51

what mechanism to avoid being phagocytosed is utilized by: Pneumococci a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 51

b) thick hydrophilic capsule

Question 52

what mechanism to avoid being phagocytosed is utilized by: Streptococci a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 52

c) M protein to avoid opsonization

Question 53

what mechanism to avoid being phagocytosed is utilized by: Borrelia burgdorferi and Leptospira a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 53

d) Factor H binding to mask C3b and block MAC

Question 54

what mechanism to avoid being phagocytosed is utilized by: Salmonella, E.coli, and Pseudomonas a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 54

e) Type III secretion system (injection of modulators)

Question 55

what mechanism to avoid being phagocytosed is utilized by: Mannheimia hemolytica and Fusobacterium necrophorum a) Protein A, which competitively binds the Fc portion of Ab b) thick hydrophilic capsule c) M protein to avoid opsonization d) Factor H binding to mask C3b and block MAC e) Type III secretion system (injection of modulators) f) kill the phagocytes w/ leukotoxins

Answer 55

f) kill the phagocytes w/ leukotoxins

Question 56

Listeria monocytogenes is taken up into even non-phagocytic cells and this is mediated by what?

Answer 56

Internalin

Question 57

once ingested, Listeria monocytogenes produces what that allows it to escape the phagosome?

Answer 57

Listeriolysin (LLO)

Question 58

what immune evasion mechanism is utilized by human hepatitis C? a) virokines/immunoevasins b) block expression of MHC I c) decrease MICB expression d) alter T cell function specifically

Answer 58

a) virokines/immunoevasins

Question 59

HIV, FIV, and FeLV combat the immune system by: a) infecting lymphocytes and impairing their ability to function b) using a period of latency to hide then recrudescing when system is stressed c) producing enzymes that inhibit apoptosis

Answer 59

a) infecting lymphocytes and impairing their ability to function

Question 60

Herpesviruses combat the immune system by: a) infecting lymphocytes and impairing their ability to function b) using a period of latency to hide then recrudescing when system is stressed c) producing enzymes that inhibit apoptosis

Answer 60

b) using a period of latency to hide then recrudescing when system is stressed and c) producing enzymes that inhibit apoptosis

Question 61

Pox viruses combat the immune system by: a) infecting lymphocytes and impairing their ability to function b) using a period of latency to hide then recrudescing when system is stressed c) producing enzymes that inhibit apoptosis

Answer 61

c) producing enzymes that inhibit apoptosis

Question 62

the break out of K9 influenza (2015 in US for example) ties back to: a) antigenic drift b) antigenic shift

Answer 62

b) antigenic shift

Question 63

Salmonella enterica utilizes which strategy to avoid our immune system: a) antigenic variation b) antigenic diversity

Answer 63

b) antigenic diversity

Question 64

Streptococcus pyogenes utilizes which strategy to avoid our immune system: a) antigenic variation b) antigenic diversity

Answer 64

b) antigenic diversity

Question 65

Streptococcus pneumoniae utilizes which strategy to avoid our immune system: a) antigenic variation b) antigenic diversity

Answer 65

b) antigenic diversity

Question 66

Borrelia recurrentis utilizes which strategy to avoid our immune system: a) antigenic variation b) antigenic diversity

Answer 66

a) antigenic variation

Question 67

Trypanosomes utilizes which strategy to avoid our immune system: a) Antigenic Variation b) Antigenic Diversity

Answer 67

a) Antigenic Variation

Question 68

what two organisms work synergistically to cause Bovine Respiratory Disease (BRD)?

Answer 68

-virus: Bovine Herpesvirus 1 (BHV-1) -bacteria: Mannheimia hemolytica (M. hemolytica)