Purification of african malignant catarrhal fever virus using a two-phase aqueous polymer system

The WC11 isolate of malignant catarrhal fever virus (MCFV) was purified by a method employing phase separation of the virus in an aqueous polymer system. Virus was grown in primary bovine thyroid cells. The virus released into the extracellular medium was purified. Initial concentration and partial purification of MCFV occurred after separation of the virus into the dextran phase following the addition of 10% (w/v) polyethylene glycol and 8% (w/v) dextran T10 to the extracellular virus. Further purification was achieved by centrifugation into a 20% (w/v) ficoll cushion followed by centrifugation to equilibrium by flotation in a 15 to 36% (w/w) CsCl or 30 to 60% (w/w) sucrose gradient. Virus recovery was monitored using a plaque assay on bovine thyroid cells and ranged from 3 to 23% of the input extracellular virus.