Veterinary Vaccine Development

Question 1

What decisions are made when vaccines are developed?

Answer 1

• increase production of protective immunological memory
• decrease side effects
• maximise production and ease of use

Question 2

How are adjuvants chosen to be used?

Answer 2

• magnitude of immune response stimulated by the vaccine alone versus plus adjuvant
• level of reduction in side effects of dosage
  -The type of immune response simulated by the vaccine alone

Question 3

What does DIVA stand for?

Answer 3

Differentiating infected from vaccinated animals

Question 4

How is DIVA solved?

Answer 4

• Positive marker strategy (addition of a unique tag for vaccine antigen)
• Negative marker strategy (vaccine lacks a pathogen molecule - test detects antibodies against that specific antigen)

Question 5

What are the cons of live attenuated vaccines?

Answer 5

• risk of reversion to virulence (pathogens damage ability)
• storage challenges
• production challenges
• severe disease in immunocompromised

Question 6

What are the categories of modern vaccine technologies?

Answer 6

category 1 - Recombinantly expressed antigens
category 11 - genetically attenuated organisms
category 111- live recombinant organisums
catagory 1111 - DNA/RNA vaccine

Question 7

How do catagory 1 vaccines work?

Answer 7

• add a key antigen gene into another organism and then purify it for vaccination

Question 8

Why are category 1 vaccines used?

Answer 8

• ability to produce lots of known antigen
• negative or positive marker in DIVA testing
• EXAMPLE = LYME DISEASE VACCINE FOR DOGS

Question 9

How do category 11 vaccines work?

Answer 9

• Remove key virulence factor (such as an enzyme for replication) from pathogen

Question 10

Why are category 11 vaccines used?

Answer 10

• similar advantages to attenuated for strong, appropriate immune response
• no issues of reversion as designed attenuation
• DIVA negative marker possible (seen in strangles vaccine)
  -EXAMPLE= PSEUDORABIES IN PIGS

Question 11

How do category 111 vaccines work?

Answer 11

• express your target antigen in a different organism eg. a live virus

Question 12

Why use category 111 vaccine method?

Answer 12

• easy to manipulate
• elect the strong immune response
• DIVA positive and negative marker possible
• EXAMPLE = RABBIES-VACCINIA VACCINE (G -PROTIEN)

Question 13

How do Category IV vaccines work?

Answer 13

• mRNA encoding key protein/ peptide antigen inside a lipid nanoparticle = fuses with host cell and translates
• loaded onto MHC class 1 and 11
• also secreated out of cells