Lecture 16 Flashcards
What is the purpose of a vaccine
Produce antibodies - ideally cytotoxic T lymphocytes
What do B cells differentiate into?
Memory cells and plasma cells
A viral antigen is ingested by an APC, it gets degraded into peptides and loaded onto which class of molecules?
Class 2 MHC
What are some types of vaccines?
- Live attenuated virus vaccines
- Inactivated virus vaccines
- Virus vectored vaccines
- Subunit vaccines
- DNA vaccines
- mRNA vaccines
Can live vaccines that use an attenuated form of the virus replicate?
yes, but they are cleared by the recipient. This creates a strong and long lasting immune response.
Name the 2 limitations of live vaccines?
1) Bc they contain a small amount of weakened live virus, this can be problematic for immunocompromised people
2) They need to be kept cold, so they don’t travel well. This makes it difficult to deliver them to people in countries with limited access to refrigeration
Name the examples of live attenuated vaccines
- measles
- rotavirus
- smallpox
- chickenpox (VZV)
- yellow fever
How are ‘inactivated vaccines’ inactivated?
They are either chemically inactivated or heat-killed
What provides better immunity - live attenuated vaccines or inactivated vaccine
live attenuated
What are inactivated vaccines used to protect against?
- Hepatitis A
- Influenza A and B
- Poliovirus
- Rabis
Describe Viral vector vaccines - simple terms
Using one virus as a vector to bring in the genes of another virus, neither can replicate, but will develop immunity
Define - Subunit Vaccines
Subunit vaccines use specific pieces of the pathogen - like the envelope, capsid protein, sugae
What is a major advantage of subunit vaccines
- produce a very strong immune response
- can be used on almost everyone including those with weakened immune systems
What is a limitation of subunit vaccines?
may need booster shots
Which viruses used subunit vaccines?
- shingles
- hepatitis B
- HVP
- Whooping cough
- pneumococcal disease
- meningococcal disease
- Hib
What is a VLP, give example
VLP = virus like protein
Ex - empty virus shells mimic the coronavirus structure, but aren’t infectious bc they lack genetic material
What are DNA vaccines
Involves the direct introduction into appropriate tissues of a plasmid containing the DNA sequence encoding the antigen(S) against which an immune response is sought
What are some advantages of DNA vaccines?
- improved vaccine stability
- the absence of any infectious agent
- easy large scale manufacturing
- cheap
What’s better DNA or RNA vaccines - why
RNA is way better - doesn’t need to get into nucleus, just needs to fins a ribosome in the cytoplasm
What are the benefits of mRNA Vaccines?
Safe = no potential risk for infection
Efficacy = modifications make mRNA more stable
Production = cheap, fast, high yield production
What are some properties of a good mRNA vaccine?
- 5’ cap
- UTR’s
- Poly A tail
- CDS = coding sequence - has modifications for improved expression
- Purity
