Releasing cell associated virus - (Dec/13/2018 )

You could try transfecting it with infection if you have a plasmid for it. Addgene has dynamin-1.

Thank you very much, it is interesting. There are three types of dynamins: I, II, III of which type II is expressed in most cell types.

So the path could be to express the dynamin in some bacteria, purify it and then use it for cells infected with BRSV to separate virus particles?

That would be one way - a short-cut could be to transfect a mammalian expression vector with the gene encoded and see if high expression in the cell would help at all.

Oki, firstly I will try to optimize freeze-thaw and Douce homogenization.

Do you have any idea what to use to protect virus and its envelope agains freeze-thaw damage? I studied literature and found that for example, MgSO4 in combination with HEPES can by used... But what else to try?

No idea sorry. You could potentially try using glass-state inducers, such as the DMSO that you would add to cells when freezing down.