Lecture 4 Flashcards
What is meant by the term antigen?
a molecule capable of inducing an immune response
What is an antibody?
a protein produced by the immune response when it detects harmful antigens
What is the difference between cultivation of the cells and PCR?
Cultivation of cells is the gold standard we actually see evidence of the cells whereas with PCR we are only detecting DNA there is a high probability but not a certainty
What are the basic steps that are involved within the cultivation of cells?
- Take swab
- Grow
- Detect - if nothing is seen you can regrow it an then replace the medium and see if you are then able to observe the virus
What are the two main structures in eggs that would be useful for growing viruses?
Allantoic cavity- most viruses
Chorio-allantoic membrane- a very good structure for growing pox viruses
How can death of the embryonic egg be observed?
- Death of the embryo
- Pocks or plaques
- Haemagluttination of red blood cells
- Various pathologies of the embryo
What is one of the downsides of using electron microscopy for virus protection?
- unreliable and often very difficult to see
How does Serology work?
detects the presense of the viral protein not the anitbody so a positive result would indicate that it is there
What is PCR?
real time sequencing methods for nucleic acid or protein
What are the advantages of next generation sequencing and how is it different to PCR?
Unlike PCR it does not rely on having a known target. It is able to construct entire genomes on a single run
Why is it important to be able to quantify a virus?
Determining the infectious dose of an agent and vaccine production and potency.
What is a virus neutralisation test?
a test whereby the serum is continually diluted, up to a point where the antibody is able to invade and overtake the serum that is present
How does haemagglutination inhibition work?
quantitative tests- uses paired samples to attempt to determine the status of the infection
