As part of the service provided to make a recombinant virus, we produce a 50ml high titre virus stock. This is then used to produce further batches of virus inoculum for protein production.

 

Clients may also send us their virus that they have already made and we can amplify it to high titre.  We always test the virus titre of received viruses by plaque assay before proceeding to large-scale amplification of virus inoculum.

 

We can amplify virus up to 40L in one batch.  To give an idea of the volumes of virus required for protein production the following may be useful:

 

Titre of virus      MOI       Cell density         Cell volume         Volume of virus required

 

1 x 108 pfu/ml   10           2 x 106/ml           1,000ml                200ml

2 x 108 pfu/ml   10           2 x 106/ml           1,000ml                100ml

5 x 107 pfu/ml   10           2 x 106/ml           1,000ml                400ml

1 x 108 pfu/ml   10           2 x 106/ml           10,000ml              2,000ml

 

High titre virus stocks are produced using Sf9 cells in serum-free medium.  After infection, the cells are removed by centrifugation and the virus stored at 4°C in the dark.  Aliquots of virus can be prepared for long term storage.  The titre is determined by plaque-assay or baculoQUANT.