Vaccination

Question 1

What is passive immunity?

Answer 1

Transfer of active antibodies

humeral immunity

Question 2

Does passive immunity give slow or fast protection?

Answer 2

Fast

Question 3

How can antibodies be transferred in passive immunity?

Answer 3

Through placenta to foetus
Through colostrum
Artificially via oral medication or IV/IM

Question 4

Vaccinations can involve artificial passive immunity. Where are the antibodies derived from?

Answer 4

Donor animals

Have high titres of a specific antibody

Question 5

What are the limitations of giving artificial passive immunity in vaccinations?

Answer 5

Only relevant to disease that require humoral response for protection
Risk of hypersensitivity to IgG injections

Question 6

What cells do cytotoxic T lymphocytes kill?

Answer 6

Virus infected cells
Cancer cells
Cells containing intracellular bacteria

Question 7

What is active immunisation?

Answer 7

Immunisation with microbial products to induce long-term immunity and memory

Question 8

Why are subcutaneous vaccines so useful?

Answer 8

Skin has Langerhans cells - monocyte derived epidermal cells
Langerhans are precursors of dendritic cells - capture and process antigens in skin
Travel in lymph nodes and effectively stimulate T cells

Question 9

What is the main function of dendritic cells? (Part of immunity, not the same as dendrites!)

Answer 9

Process antigen material and present it on the surface to T-cells

Question 10

Active immunisation can be systemic or mucosal (local). How may vaccines for mucosal/local infections be given?

Answer 10

Intranasally e.g. Bordatella bronchiseptica for kennel cough
Orally

Question 11

Vaccines may contain adjuvants. What are these? Are they specific or non-specific?

Answer 11

Enhancers of immune response to non-living vaccines

Non-specific

Question 12

How do adjuvants work to enhance immune response? (adjuvants in non-living vaccines only)

Answer 12

Slow release of vaccine antigens to enhance recognition and response

Question 13

Give an example of an adjuvant used in vaccines

Answer 13

Magnesium salts

Aluminium salts

Question 14

What are the differences between living and inactivated viruses in terms of adjuvants and cost?

Answer 14

Living - don’t need adjuvants, cheap

Inactivated - need adjuvants, more expensive

Question 15

What type of vaccine (living or inactivated) is more likely to contain contaminating organisms?

Answer 15

Living vaccine - also more likely to cause disease through residual virulence

Question 16

What type of vaccine (living or inactivated) is more likely to cause hypersensitivity reaction?

Answer 16

Inactivated vaccine

Question 17

What type of vaccine (living or inactivated) requires more than one inoculating dose?

Answer 17

Inactivated vaccine

Question 18

What are the advantages/disadvantages to dead vaccines?

Answer 18

Safer than living
Have to be administered more often
Need adjuvants for effective immunity

Question 19

What is used to cause the immune response in inactivated vaccines?

Answer 19

Killed organism
Inactivated toxins
Fragments of cells (e.g. part of cell wall)
DNA itself

Question 20

Why do live vaccines not cause disease?

Answer 20

They can sometimes!

They are attenuated = mutants selected that reduce virulence but retain antigenicity

Question 21

What is used to cause the immune response in live attenuated vaccines?

Answer 21

Inactivated organism (whole virus/bacteria - mutants)
Proteins/polypeptides derived from virus/bacteria

Question 22

What are the functions of vaccination?

Answer 22

Prevent disease

Stop shedding of infectious viruses

Question 23

What is herd immunity?

Answer 23

The indirect protection from infection, in a susceptible population
Brought about by the presence of immune individuals