Abstract: This invention is directed to a continuous process for producing viral particles by providing in a perfused growth medium a population of viable virally infected non-lytic cells, and removing medium containing said cells at a rate to maintain the steady-state log-phase growth of cells remaining in the perfused growth medium. The invention is also directed to a process for purifying retroviral particles by passing a solution comprising the retroviral particles and contaminants through an anion exchange resin, and eluting the retroviral particles from the resin. The preferred exchange resin is a tentacle anion exchange resin.

Abstract: The present invention provides a fail-safe combination of chemical and physical means for rendering a blood product which comprises a labile blood protein free of viruses without incurring protein denaturation. The blood product is contacted with an effective amount of a selected chemical disinfectant, preferably, sodium thiocyanate in combination with a physical process, preferably, ultrafiltration. The blood product may be plasma, serum, plasma concentrate, cryoprecipitate, cryosupernatant, plasma fractionation precipitate or plasma fractionation supernatant containing viruses such as hepatitis or human immunodeficiency virus.