Vaccine Delivery 1

Question 1

Describe how vaccines work

Answer 1

Vaccines contain antigens
Antigens trigger a primary immune response
T cells and B memory cells are then produced for the specific pathogen
Upon reinfection with the same pathogen a faster secondary immune response is triggered

Question 2

Is the effect of a vaccine permanent?

Answer 2

Immunity may not be permanent
Booster vaccine may be required

Question 3

List the characteristics of an ideal vaccine

Answer 3

Stimulate immune response with causing symptoms of disease
Be effective in everyone
Cheap to produce
Easy to manufacture
Be stable
Be available as oral preparation

(However this does not exist, lol , Pharmacy L)

Question 4

What are the advantages of the Oral Polio Vaccine (Sabin Vaccine)

Answer 4

Easily administered (oral)
Protects against infection of wild type polio
Promotes antibody production in the GI tract
Cheap

Question 5

What are the disadvantages of the Oral Polio Vaccine (Sabin Vaccine)

Answer 5

Risk of contracting polio from the vaccine

Question 6

List the components of the innate immune system

Answer 6

Skin - physical barrier + fatty acid secretion

Mucous membranes - Mucociliary Clearance

Blood - phagocytes

Ears - lysozymes hydrolyse pathogen cell wall

Stomach - stomach acid is unsuitable environment

Question 7

Describe the immune response when a pathogen enters the body (5 main points)

Answer 7

1. Bacterial replication causes tissue damage
2. Cell damage causes activation of local lymphocytes
3. Pathogens are recognised by T cells
4. B cells produce antibodies
5. Antibodies bind to surface receptors on pathogens

Question 8

What cells are involved in the humoral response

Answer 8

B cells
Antibodies

Question 9

What cells are involved in the cell mediated response

Answer 9

T cells
e.g. Helper T cells and Killer T cells

Question 10

What are immunoglobulins also known as

Answer 10

Antibodies

Question 11

Describe the structure of an antibody

Answer 11

4 polypeptides
- 2 identical heavy chains
- 2 identical light chains

Held together by disulphide bridges

Question 12

What are the 5 classes of antibodies

Answer 12

IgG
IgA
IgM
IgE
IgD

Question 13

What does the variable region of an antibody determine

Answer 13

What antigen the antigen binding site will bind to

Question 14

How are antibody-antigen complexes removed from the body

Answer 14

Removed by phagocytosis by macrophages

Question 15

Which class of antibodies is mainly involved in primary response

Answer 15

IgM

Question 16

Which class of antibodies is mainly involved in secondary response

Answer 16

IgG
(Higher binding affinity to the antigen)

Question 17

What are the 3 problems with the immune response?

Answer 17

Autoimmunity - body cannot distinguish self and non-self antigens
Immunodeficiency - inadequate immune response
Hypersensitivity - overactive response to certain antigens

Question 18

What are the 2 types of immunisations?

Answer 18

Active immunisation and Passive immunisation

Question 19

What is active immunisation?

Answer 19

Stimulation of immune response through deliberate exposure to a pathogen
With the aim of forming immunity to the antigen

Question 20

What is passive immunisation?

Answer 20

Introducing pre-formed antibodies to a specific pathogen
Does not evoke immune response

Question 21

List the 5 main vaccine types

Answer 21

Inactivated
Attenuated
Subunit
DNA/RNA
Toxoids

Question 22

Give an example of each type of vaccine

Answer 22

Inactivated - hepatitis A
Attenuated - MMR
Subunit - Streptococcus Pneumoniae
DNA/RNA - IM injection of DNA/RNA which encodes for viral pathogen
Toxoids - Tetanus

Question 23

How does an inactivated virus work?

Answer 23

Immune system sense virus but the virus is unable to replicate and spread as it has been ‘killed’

Question 24

How do subunit vaccines work?

Answer 24

Made of H and/or N proteins only
H and N proteins are able to generate an immune response

Question 25

How does a DNA vaccine work?

Answer 25

Gene for H protein is isolated It is injected into human body Human cells then produce H protein Generates immune response to H protein

Question 26

What is the difference between a RNA and DNA vaccine?

Answer 26

RNA is one step ahead DNA vaccines need to be decoded in the nucleus RNA vaccines are processed directly in the cytosol

Question 27

What is the purpose of an adjuvant in a vaccine?

Answer 27

To help provoke an early, long-lasting immune response with less vaccine

Question 28

What are the benefits of using an adjuvant in a vaccine?

Answer 28

Reduce cost (reduces amount of antigen require) Reduce need for boosters (provides long lasting response)

Question 29

What is the mechanism of action of an adjuvant?

Answer 29

Enhance the passage of the antigen to the local node + Depot effect - prolong the delivery of the antigen

Question 30

Name a commonly used adjuvant for a vaccine

Answer 30

Aluminium Salt e.g. AlOH3

Question 31

What are the issues with aluminium salts as adjuvants?

Answer 31

Cannot be frozen, have to be refrigerated (more expensive) Can interact with the antigen Vaccine cannot be used on a mucosal membrane Do not work with all antigens