Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

IMMUNO my version > Vaccination > Flashcards

Vaccination Flashcards

1
Q

What is a vaccine?

A

A substance used to stimulate the production of antibodies and provide immunity against one or more diseases

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

What is the aim of immunisation?

A

To provoke immunological memory and protect individuals against a particular diseases if encountered

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

What are some characteristics of the ideal vaccine?

A

Safe
Easy to administer
single dose, needle free
Cheap
Active against all variants
Life-Long protection

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

What three things can vaccines work to do?

A
  1. Prevent entry - vaccine stimulates production of antibodies which bind to virus and stop it harming cells
  2. Boosting immune response - the antigens in the vaccine stimulate CD4 Helper T cells
  3. Killing Infected cells - CD8 killer cells detect the foreign antigens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the characteristics of immune memory?

A

The memory cells can multiply much faster and produce a stronger immune response by generating antibodies which have a higher affinity for antigens

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

What is R0?

A

The basic reproduction number - the number of cases one case generates on average over the course of their infectious period

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

What happens if R0 <1?

A

The infection will die out eventually

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

What happens if R0>1?

A

Then the infection will be able to spread in the population

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

What is herd immunity?

A

Those people who are immunised against the virus can help protect those who are not as the virus will be less transmissible amongst those protected

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

What are the four components of a vaccine?

A

antigen
adjuvant
stabilising factors eg buffers
water

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

What is an adjuvant?

A

Substances used alongside the antigen to illicit a more robust immune response than if the antigen was just used alone

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

How do adjuvants work?

A

They induce danger signals that activate DC’s to present antigen to T cells

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

What adjuvant is normally found in vaccines?

A

Alum

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

name some novel adjuvants in vaccines

A

AS03
MF59

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

Mechanism of adjuvant action?

A
  1. Adjuvant stimulates DC
  2. DC take up antigen and moves to secondary lymphoid tissue
  3. Upregulation of co-stimulatory signalling and cytokines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is an Inactivated Toxoid Vaccine?

A

A chemically inactivated form of toxin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Benefits of inactivated toxoid vaccines?

A

Cheap, Safe

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Mechanism of Inactivated Toxoid Vaccines?

A

The vaccine induces antibody which blocks the toxin from binding to cells (nerves in tetanus’ case)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do recombinant protein vaccines work?

A

Surface antigen gene is isolated
Inserted into another organism
Modified cell produces antigen / vaccine (protein)
Induces classic neutralizing antibodies in human

20
Q

give an example of a disease which uses recombinant protein vaccines

A

Hep B

21
Q

What are the disadvantages of a recombinant protein vaccine?

A

Expensive

22
Q

what is a major flaw with recombinant protein vaccines?

A

The shape of the protein before and after the growth in a vector is different.
Hence, the antibodies produced against the vaccine protein would be ineffective against a proper infection.
This is common problem with virus’ but can easily be solved.

23
Q

what is a problem associated with inactivated toxoid and recombinant protein vaccines?

A

Some bacteria have capsules which prevent B cell responses, so need alternative approaches against these

24
Q

What is a live attenuated pathogen vaccine?

A

Vaccine where the pathogen has been weakened, but is still able to replicate so it can trigger an immune response, which is almost identical to what happens in a natural infection

25
Q

What is an example of an live attenuated pathogen vaccine?

A

MMR, BCG

26
Q

What are the advantages and disadvantages of a live attenuated pathogen?

A

Advantages: Strong immune response is generated
Disadvantages: Since it is a pathogen, it may infect the immunocompromised, can revert to virulence, attenuance may lose key antigens

27
Q

What is a dead pathogen vaccine?

A

Rather than using a single antigen, it’s a chemically killed pathogen using formaldehyde

28
Q

what is the mechanism of dead pathogen vaccines?

A

induces antibody and T cell responses

29
Q

what is an example of a dead pathogen vaccine?

A

influenza

30
Q

What are some disadvantages of a dead pathogen virus?

A
  • killing the pathogen can sometimes alter the antigen
  • requires the capacity to grow the pathogen
  • virus can mutate whilst growing - antigenic drift
31
Q

what is a conjugate vaccine?

A

Where the polysaccharide coat component is coupled to an immunogenic “carrier” protein which enlists CD4 help to boost B cell response to the polysaccharide, as B cell react strongly to the polysaccharides on some bacteria

The polysaccharide is considered a highly immunogenic part

32
Q

give an example of a conjugate vaccine

A

s.pneumoniae

33
Q

how do conjugate vaccines work?

A
  • A DC engulfs the whole antigen and presents the protein part onto MHCII. A B cell takes up the polysaccharide part of the antigen and presents it onto its MHCII
  • Tfh is primed by DC through interacting with the DC’s MHCII presented peptide and then goes to the matching B cell (presenting the same thing) and boosts it
34
Q

Why do we need new vaccines?

A
  • changing demographics
  • changing environments
  • new diseases emerging
  • increasing resistance
  • old diseases we cant fix
35
Q

What type of vaccine is Diptheria? d

A

Toxin Based

36
Q

What type of vaccine is MMR?

A

Live attenuated

37
Q

What type of vaccine is BCG?

A

Live attenuated

38
Q

What type of vaccine is Influenza split vaccine

A

Dead pathogen virus

39
Q

What type of vaccine is polio?

A

Live attenuated

40
Q

What are some barriers to future vaccine development?

A

Time, cost and expertise required to develop vaccines
scientific challenges
Vaccine safety
Public expectation of free vaccination

41
Q

What makes it harder to generate vaccines?

A

Classic immune memory will only recognise one strain

Therefore vaccine antigens need to cover all the variety

42
Q

What are the phases of a clinical trial?

A

Pre-clinical

Phase 1 - safety in humans

Phase 2 - mixture of safety and efficacy studies

Phase 3 - shown to be safe and effective

FDA review (MHRA in UK) - licensing

Phase 4 - licensed and approved → then goes into large groups of people + more monitoring

43
Q

What needs to be considered for the scheduling of the vaccine?

A

Aim

Need

Scheduling with other vaccines

Availability

Cost

Population accessibility

Cultural attitudes and practices

Facilities available for delivery

44
Q

Give an example of a high variable virus?

A

HIV

45
Q

how do conjugate vaccines work?

A
  • A DC engulfs the whole antigen and presents the protein part onto MHCII. A B cell takes up the polysaccharide part of the antigen and presents it onto its MHCII
  • Tfh is primed by DC through interacting with the DC’s MHCII presented peptide and then goes to the matching B cell (presenting the same thing) and boosts it

IMMUNO my version (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions