Immunity Against Infection II Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

How can viruses be EC when usually ic

A

Early stage of infection before they get into cells

Need complement, ab, phagocytosis, neutralisation,MHC II presentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is needed once they become ic

A

MHC I presentation on all cells

Activate th1 to activate CD8 and NK cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the first response to viral infection

A

Type 1 ifn a and ifn b

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What do ifn a and b induce which prevents viral replication

A

2’-5’ oligoadenylate synthetase : degrades rna

Kinase PKR : inhibits viral protein synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Other than activating oligoadenylate synthetase and kinase pkr, what does ifn a and b do

A

Upregulate MHC I (stimulate CD8)
Upregulate dendritic and macrophage cells (apc)
Induce NK anti viral response
Induce chemokines to recruit lymphocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

After induction of ifn a and b which stimulates apc and NK, what is released to promote th1 response (CD8 and NK stimulation)

A

Type II ifn y (from NK cells and apc like macrophages)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is an issue with ifn a used to treat cancers

A

Can cause too much chemokine/cytokine production forming a storm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

How do NK cells kill viral cells after stimulation by both ifn a/b and also by ifn y th1 response

A

Granules with perforin and granzymes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Which NK receptors activate them to kill viral cells by releasing granules

A

Activating receptors (recognise viral cell things like carbohydrates)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Which receptors inhibit killing of healthy cells by NK cells

A

Inhibitory receptors. They when bound non specifically to MHC I will make NK cells not kill it (killed by CD8 instead)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Which response comes last to clear viral infections

A

Cell mediated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What activates CD8

A

Ifn y which stimulates th1 response

Also MHC I presentation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Which2 ways do CD8 cells kill viral cells (apoptosis)

A

Secrete granzymes and perforin

Or binding of its FAS ligand to a Fas on host cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What ensures local release of granules from CD8

A

Cell to cell contact via cams

Cytoskeleton rearrangements

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What cytokine do CD8 release important in viral killing

A

Ifn y

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Why are antibodies important in viral infections

A

In early stages before cell entrance.
Antibodies stop adherence eg iga
They cause complement lysis of enveloped viruses
Cause opsonisation via macrophages

17
Q

Which antigens from influenza are used for the vaccine to produce antibodies

A

Hemagluttinin

Neuraminidase

18
Q

What cells does hiv target

A

CD4, macrophages and dendrites (leads to opportunistic infections like candida,kaposi sarcoma)

19
Q

Which cells control hiv to an extent

A

CD8 responses

20
Q

Why is hiv hard to vaccinate

A

Antibodies don’t protect against it

21
Q

What is dampened down by sars cob 2 which causes cytokine storm instead and viral replication

A

Ifn type 1

22
Q

Which type of prr are inhibited by covid

A

Rig 1

23
Q

What pro inflammatory tf is upregulated by covid

A

Nfkb

24
Q

Why are antibodies important for parasite killing

A

Allow opsonisation
Adcc - coat large parasites for eosinophil killing via fc receptors
Also can cause lysis via complement

25
Q

Which parasite is killed by igE stimulating eosinophils

A

Helminths - coated and killed

26
Q

Why is the T cell/macrophage response also important for parasites

A

Some are intracellular and can survive in vesicles/macrophages

Hidden from antibody response

27
Q

Give an example of a parasite ic so needs macrophages/th1 cell response

A

Leishmania (stay in macrophages)