AW L2 Influenza

Question 1

What type of virus is flu?

Answer 1

Orthomyxovirus

enveloped

Question 2

What type of genetic info is in flu?

Answer 2

ssRNA

Question 3

What receptors does flu recognise?

Answer 3

Sialic acid receptors

Question 4

Important viral components: (4)

Answer 4

----
Antigenic:
Hemagglutinin
Neuraminidase
vRNA
----
Non-structural protein

Question 5

What is transcribed when flu enters host?

Answer 5

NFkB

Question 6

NFkB causes expression of what (3)

Answer 6

TNA alpha
IFN beta
IL-8

Question 7

after initial infection cells continue to….

Answer 7

keep the Th1 response cycle going by producing more inflammatory cytokines

Question 8

List the cytokines involved in the Th1 response

Answer 8

IFNγ
TNFα
IL-2
IL-3
IL-8
IL-12
IL-18

Question 9

Flu effect on IFN binding

Answer 9

inhibits

& inhibits functions of interferon-induced proteins

Question 10

Flu effect on MHC ecpression

Answer 10

inhibits expression of MHC I and MHC II

Question 11

Flu inhibits or activates apoptosis

Answer 11

inhibits

Question 12

Flu inhibits or activates NK function

Answer 12

inhibits

Question 13

Long term host response from IFNγ production

Answer 13

boost chemokine gene expression
activates macrophages
antigen presentation
continual development of specific cell-mediated immunity

Question 14

Th2 response involves what ILs?

Answer 14

4,5,6
10
13
25

Question 15

Long term flu response results in …………….. T cell

Answer 15

stimulated

Question 16

Long term flu response results in …………… B cell

Answer 16

matured

Question 17

Long term flu response results in ……………….. production

Answer 17

Antigen specific IgG

Question 18

“antigen”

Answer 18

a molecule that provokes a specific immune response

Question 19

Antigen may be a component of….

Answer 19

microorganism

proteins/glycoproteins on RBC/transplanted tissue cells

Question 20

A single protein may have many antigenic determinants called

Answer 20

epitopes - each stimulate a distinct immune response

Question 21

Immunity can be acquired in 2 ways:

Answer 21

Active

Passive

Question 22

What is passive immunity?

Answer 22

results from obtaining another individuals antibodies (across placenta)

Question 23

What is active immunity?

Answer 23

results from activation of an individuals own lymphocytes

Question 24

2 ways to get active immunity

Answer 24

pathogen or vaccination

Question 25

Primary immune response is...

Answer 25

first encounter with the foreign antigen

Question 26

In primary response are all cells activated?

Answer 26

No - only a few B or T cells recognise the antigen

Question 27

In secondary immune response who recognises the antigen?

Answer 27

Large clone of memory cells | and the immune response is more effective

Question 28

Subtypes of flu are distinguished by....

Answer 28

the antigenic properties of HA and NA

Question 29

How many -HA -NA subtypes are found in influenza type A (in humans)

Answer 29

3,2 H1, H2, H3 N1, N2

Question 30

Antigenic drift is....

Answer 30

gradual accumulation of mutations that allow HA to escape neutralizing antibodies

Question 31

Epidemic strains are thought to have changes in ........................... antigenic sites

Answer 31

3 +

Question 32

Antibodies are raised against antigenic sites on what part of the flu?

Answer 32

HA

Question 33

A specific vaccine needs to be produced against each .................. of flu

Answer 33

serotype

Question 34

Do drugs need to be selective for serotype?

Answer 34

No - active against all BUT no lasting protection

Question 35

Other problems with drugs against vaccines?

Answer 35

resistance

Question 36

Advantage of drugs over vaccines

Answer 36

can stockpile - vaccines need to be produced in time

Question 37

What does a flu vaccine contain?

Answer 37

Trivalent Inactivated Vaccine | combination of two As and one B

Question 38

How is vaccine administered

Answer 38

IM

Question 39

How to grow a vaccine

Answer 39

``` Co-infect chicken eggs with strain and A/PR/8/34 Select seed strain Propagation of seed strain Purification Treatment ```

Question 40

How do we purify the vaccine?

Answer 40

Zonal centrifugation

Question 41

What are the 3 treatment options and what do the produce?

Answer 41

Formaldehyde - inactivated vaccine ethyl ether - split vaccine Detergents & purification of HA - subunit vaccine

Question 42

How long does it take to make a vaccine(ish)?

Answer 42

9 months

Question 43

3 disadvantages of egg propagation

Answer 43

time consuming expensive incompatible with High Path avian influenza strains (kills the egg)

Question 44

Flu A or B is more prevalent in children?

Answer 44

B

Question 45

Live attenuated vaccines are administered via

Answer 45

nasal spray

Question 46

How are live attenuated vaccines made

Answer 46

cold-adapted influenza viruses propagated by infection of cells in culture and manufactured in eggs

Question 47

Live attenuated vaccine induces...

Answer 47

neutralising and mucosal antibodies - but the extent to which it induces t cell immunity is not yet known