Lecture 10 - Evasion of host defences and immunopathology

Question 1

which evasion mechanism is this describing?:
- inhibition of MHC I presentation
- uptake of host molecules
- priveleged sites e.g herpes laying latent in the CNS

Answer 1

number 1 - concealment of antigens

Question 1

what are the 4 evasion mechanisms?

Answer 1

1 - concealment of antigens
2 - antigenic variation
3 - immunosuppression
4 - interference with effector mechanisms

Question 2

which evasion mechanism is this describing? :
- large number of antigens e.g in s.pneumonia
- mutations such as antigenic shift/drift

Answer 2

number 2 - antigenic variation

Question 3

which evasion mechanism is this describing? :
- infection of immune cells e.g HIV with T cells
- induction of T reg e.g in measles and leishmania

Answer 3

number 3 - immunosuppression

Question 4

which evasion mechanism is this describing? :
- IgA broken down e.g Neisseria
- Fc binding molecules interfered with e.g measles
- binding to cytokines e.g smallpox
- inhibition of phagocytic killing e.g tuberculosis

Answer 4

number 4 - interference with effector mechanisms

Question 5

define immunopathology

Answer 5

pathology of an infectious disease resulting from the effects of a pathogen or host responses (innate or specific)

Question 6

via which toll like receptor do LPS induce macrophage cytokine secretion?

Answer 6

TLR 4

Question 7

Which cytokine increases vascular permeability, resulting in fluid drainage to LN and fever?

Answer 7

TNF alpha

Question 8

is ebola virus:

enveloped or non enveloped?
segmented or non segmented
-ve or +ve stranded?
DNA or RNA?

Answer 8

enveloped
non segmented
-ve stranded
RNA

Question 9

in ebola virus, vascular permeability is increased and a coagulation cascade induced. what two things do these result in? (think cytokines and fever)

Answer 9

haemorrhagic fever
cytokine storm

Question 10

antigenic shift is related to which set of viruses (think pandemic)?

Answer 10

influenzae

Question 11

true or false? antigenic shift is a gradual change in a viruses genetic makeup?

Answer 11

false, antigenic shift is an ABRUPT change

antigenic drift is a gradual change

Question 12

antigenic drift is a …… change to a viruses genetic makeup?

Answer 12

gradual

Question 13

in which cell type does herpes lay latent in?

how does it manage to do this?

Answer 13

in neurons

because they are non replicating