CMB2004/L11 Immunisation

Question 1

Give an example of active natural immunity.

Answer 1

Natural infection

Question 2

Give an example of active artificial immunity.

Answer 2

Immunisation

Question 3

Give an example of passive natural immunity.

Answer 3

Placental transfer of maternal IgG

Question 4

Give an example of passive artificial immunity.

Answer 4

Human IgG (normal or immune)

Question 5

Describe passive immunity.

Answer 5

Short-lived (IgG half-life 3 weeks)
Hypogammaglobulinaemia in infants as maternal IgG declines
IVIgG every 2-4 weeks or immunodeficiency to maintain protective levels
Tetanus antitoxin

Question 6

Describe active immunity.

Answer 6

Exploits immunological memory

Question 7

Compare the secondary immune response to primary. (3)

Answer 7

Faster
Greater in magnitude
May be qualitatively better

Question 8

Who is protected by herd immunity? (2)

Answer 8

Individual
Population

Question 9

Give 3 requirements of an effective vaccine.

Answer 9

Safe
High level of protection
Long-lasting protection
Right type of response
Low cost
Stable
Easy to administer
Minimal side-effects

Question 10

Give the 5 types of vaccine.

Answer 10

Inactivated
Attenuated
Subunit
Toxoid
Conjugate

Question 11

What is an attenuated vaccine?

Answer 11

Live but virulence disabled organisms
E.g., Salk polio vaccine, smallpox, sabin, MMR, BCG

Question 12

What is a subunit vaccine?

Answer 12

Protein fragments
E.g., Hep B, pneumococcal polysaccharide

Question 13

What is a toxoid protein?

Answer 13

Bacterial toxin

Question 14

What is a conjugate vaccine?

Answer 14

Something with low antigenic property covalently bound to something with high
E.g., Hib, MenC, Pneumococcal Prevnar 13

Question 15

Give 2 pros to live vaccines.

Answer 15

Single dose effective
May be given by natural route
May induce local and systemic immunity
May induce right type of response

Question 16

Give 2 cons of live vaccines.

Answer 16

Reversion to virulence
Possibility of contamination
Susceptible to inactivation
Causes disease in immunocompromised host

Question 17

Describe polio.

Answer 17

Enterovirus
Faecal-oral spread
+ve sense RNA

Question 18

How do conjugate vaccines work?

Answer 18

Convert TI-2 polysaccharide antigen to TD form

Question 19

What are adjuvants?

Answer 19

Substances administered with an antigen to promote immune response
- by providing a ‘depot’
- Immunostimulatory properties

Question 20

Give 2 ways in which adjuvants can work.

Answer 20

Activate dendritic cells via TLRs or NLRs
Cause release of endogenous danger signals
Promote antigen uptake by dendritic cells
Stimulate release of chemokines/cytokines
Promote cross-presentation of exogenous antigens by class I

Question 21

Give 2 animal adjuvants.

Answer 21

Freunds: oil in water emulsion
Freunds complete: also contains mycobacteria

Question 22

What is used in human adjuvants?

Answer 22

Aluminium hydroxide or aluminium phosphate

Question 23

What is MF59 adjuvant?

Answer 23

Squalene based oil in water emulsion
Licensed since 1997, used in some flu vaccines

Question 24

What is AS03 adjuvant?

Answer 24

Includes squalene and vitamin E
Approved 2008 for GSKs H1N1 flu vaccine

Question 25

What is AS04 adjuvant?

Answer 25

Alum plus monophosphoryl lipid A (LPS derivative)
Approved 2005 for HBV vaccine