PURIFICATION OF INFECTIOUS PANCREATIC NECROSIS VIRUS BY ANION-EXCHANGE CHROMATOGRAPHY INCREASES THE SPECIFIC INFECTIVITY

An improved method for the isolation and purification of infectious pa ncreatic necrosis virus (IPNV) is described. Virions released into the clarified growth medium are adsorbed to an anion exchange resin of di ethylaminoethyl cellulose at pH 8.1. IPNV together with the likewise r eleased and accumulated excess pool of the precursor to the major caps id protein, ICP62, are eluted at a salt concentration between 100 and 125 mM NaCl. The bovine serum albumin content of the growth medium sup plement also elutes close to this position. Upon one step of combined sucrose- and CsCl-gradient centrifugation the recovered viruses displa y lower levels of aggregation, higher specific nucleic acid contents a nd an approximately 350% higher specific infectivity as compared with pools of viruses processed in parallel and isolated according to the e stablished method relying on precipitation with poly(ethylene glycol).