Lecture 7 Flashcards
How many vaccine preventable diseases are there?
27
6-in-1 vaccine
Diphtheria, tetanus, pertussis, polio, Hib, hepatitis B
Licensed maternal vaccines
Pertussis, Influenza
Goals of prophylactic vaccines
- Efficacious (prevent infection, disease & transmission)
- Induce strong memory immune responses (durable & broad)
- Safe, well-tolerated, easy to administer, cost-effective
Antigen must have one or more of the following properties if vaccine is to be broadly applicable
- Immuno-dominant
- Critical to pathogen life cycle e.g. a toxin or required for receptor binding
- Conserved across strains
What are adjuvants?
Vaccine components that enhance the magnitude, breadth and durability of the immune response
Most adjuvants modulate the __
APC (activation of PRR by PAMPs, alter Ag presentation via MHC, increase costimulation & cytokine secretion)
Four licensed adjuvants for human use
- Aluminium salts (‘alum’): hydroxide or phosphate
- Oil-in-water emulsions: MF59, AS01
- AS04: contains MPL & alum hydroxide adjuvants
- Matrix M
How is the RNA of an RNA vaccine transported into host cells?
via lipid nanoparticles
Chemical modification to COVID-19 mRNA vaccines to prevent the immune system reacting to the introduced mRNA
Replacement of the uridine molecule with pseudouridine
What is key in RNA vaccine development?
Composition of the lipid nanoparticle
What stabilises the RNA?
an ionisable lipid molecule
Vaccine manufacturing steps
Propagation
Isolation
Purification
Formulation
Fill-Finish
What is the primary concern in phase 1 vaccine trials?
Safety (usually start in adults)
Different types of vaccines
- Live attenuated
- Inactivated
- Subunit (+/- adjuvant)
- Nucleic acid vaccines
- Recombinant viral vector
