Using poxviruses as base for vector construction

[Dorif]

What do you think about this? On the one side they have huge genome, what makes possible to insert large sequences. On the other side they replicate outside of nucleus, so they can be used only for something like CRISPR/Cas systems which guidance RNA and proteins can penetrate nucleus. Of course I do not propose to use Variola major virus. I think something like fowlpox or myxoma viruses will be good for this. And currently I have both myxoma (strain V-82) and fowlpox (strain K) viruses, both vaccinal ones.

Thanks for advice!

[Mega [Andreas Stuermer]]

I dimmly remember reading about vaccine trials where they put HIV proteins into a common vaccinia virus to elicit antibody response. Google should be able to find it-  

So the ones you have are disarmed and replication deficient? Or replicating and just deleted in all immune-system evading proteins? 

[Dorif]

They can replicate, but they cause disease only in immunodeficient animals. So, yes, they do not contain immune-system evading proteins.

[Mega [Andreas Stuermer]]

Very interesting. Does anyone know the regulations of working with them? Are they biodsafety S1? Or S3? I mean if you use your brain, it will tell you that there is absolutely no harm in a virus that has been completely depleted in its weapons. But regulatory bodies may tend to differ - the label Pox may sound scary. 

[Dorif]

Yes, one detail: fowlpox virus can not replicate in mammalian cells, myxoma virus can replicate in rabbit cells or in some of the human tumor cells (it is now researched as perspective oncolytic virus). If we want to create vector capable to replicate in human cells we must replace some of the replication-related genes of these viruses with Variola, Vaccinia or Cowpox ones. Or simply use Vaccinia or Cowpox as basis.

[Dorif]

Fowlpox and myxoma viruses are not pathogenic for humans. So, they are BSL1, maximum BSL 2. Vaccinia and cowpox sometimes can cause disease in humans, but not as severe as Variola major and were used as vaccines against it. And maybe I'll obtain vaccinia if I'll find some Soviet liophylised live smallpox vaccine.

[Dorif]

Vaccinia is BSL 2.