The present invention addresses the need to improve the yields of viralvectors when grown in cell culture systems. In particular, it has beendemonstrated that for adenovirus, the use of low-medium perfusion rates in anattached cell culture system provides for improved yields. In otherembodiments, the inventors have shown that there is improved Ad-p53 productionwith cells grown in serum-free conditions, and in particular in serum-freesuspension culture. Also important to the increase of yields is the use ofdetergent lysis. Combination of these aspects of the invention permitspurification of virus by a single chromatography step that results in purifiedvirus of the same quality as preparations from double CsC1 banding using anultracentrifuge.
