Vaccines

Question 1

Name two strategies to control pathogens and its (dis-)advantages

Answer 1

Vaccines:
- prophylaxis (mostly)
- intact immune system needed -> induces a (stable) immune response

Therapy:
- treatment after clinical manifestation
- no immune system required (mostly)
- reinfection possible

Question 2

Name examples of successful vaccines

Answer 2

• Polio: globally eradicated (nearly)
• Measles: 99.99% less cases (1941-2009)

Question 3

What is ‚implementation research‘?

Answer 3

2nd step after basic research that makes scientific findings useful and understandable for local application

Question 4

Why do we need antivirals?

Answer 4

• not everyone can get vaccinated
• not a vaccine against every virus
• emerging viruses
  development is faster
• possibly a universal antiviral

Question 5

What vaccine strategies are available?

Answer 5

• passive immunisation (give immune system compounds; also transfer of maternal ABs to fetus)
• (live-)attenuated
• inactivated
• mRNA
• vector vaccine
• subunit vaccine (recombinant & non recombinant)

Question 6

What is the aim of a vaccine?

Answer 6

induce immune system effector function:
- B cell -> neutralising ABs
- T cell -> cytotoxic CD8+ (also Th cells)

Question 7

What are the ligands for B & T cells?

Answer 7

B cell: soluble antigen or extracellular pathogen

T cell: epitope peptide on MHC

Question 8

What is an attenuated vaccine and name an example?

Answer 8

• virus that is reduced in virulence
• virus is passaged over different non human cells to loose virulence
• potential immune response
• risk of reversion/disease
• example: OPV (oral attenuated replication-competent polio vaccine), measles

Question 9

What is an inactivated vaccine and name an example?

Answer 9

• inactivated virus
• less potent immune response
• very safe - no risk of reversion/disease

example: IPV (inactivated polio vaccine), rabies

Question 10

What is a vector based vaccine and name examples?

Answer 10

• target virus gene is delivered by a different viral vector
• specific gene delivery
• robust adaptive immune response (B & T cells)
• strong innate immune response
• combines advantages of replication competent and inactivated vaccine
• vector can‘t be used twice

examples: Ebola in VSV, AstraZeneca Covid 19 vaccine

Question 11

What is a mRNA vaccine and name examples?

Answer 11

• mRNA delivery into muscle
• fast approval
• T & B cell response
• no genomic incorporation

examples: BioNTech and Moderna Covid19 vaccines

Question 12

What is a protein vaccine and name examples?

Answer 12

• immunisation with (recombinant) protein
• after not sufficiently immunogenic

example: Shingrix (recombinant Varicella Zoster virus glycoprotein E), HBV