Viral Replication Flashcards
What is the definition of viral replication?
The formation of virions during the infection process in the target host cells.
Where do DNA viruses replicate?
In the nucleus except pox viruses which replicate in the cytoplasm.
What are viral factories?
Locations within the host cell where viruses replicate and assemble their components
Where are viral factories located?
Mainly within the nucleus and cytoplasm.
How can you detect viral replication?
The presence of viral proteins on immunofluorescence indicates viral replication.
What is viremia?
The presence of virus in the blood.
Where are viruses mainly released?
Mainly through mucosal surfaces.
What are the steps for viral infection and replication?
- Viral attachment/endocytosis
- Penetration
- Uncoating
- Genome replication and translation
- Assembly
- Virion release
How are viruses spread within the host?
- Lymphatics
- Bloodstream
How can virus be detected in tissues?
In-situ hybridization
How many proteins do small viruses (like circovirus) encode for?
2-3, enough to replicate.
Circoviruses have one for capsid formation and one for genome replication (two proteins/open reading frames)
How can viruses interfere with the host immune system?
- Interfering with cytokine production such as interferon signalling (IFN-1)
- Suppressing the synthesis or normal expression of MHC1 to prevent host cell killing by cytotoxic T cells
- Inhibition of apoptosis
- Preventing pattern recognition receptor signalling (ex. TLR)
What is the latent period?
The time between virus entry into the cell until release.
What is the eclipse period?
Time for replication. 2-12 hours.
What is tropism?
The capacity of a virus to infect specific cells (basically which cells/tissues the virus targets)
