Highly infectious plasmids carrying poliovirus cDNA are capable of replication in transfected simian cells

We examined events leading to production of infectious poliovirus upon transfection of simian cells with plasmids carrying poliovirus cDNA and simian virus 40 transcription and replication signals. The nature of the simian virus 40 promoter upstream from the poliovirus cDNA had no influence on its infectivity. A high specific infectivity was correlated with plasmid replication, dependent on expression of T antigen either encoded by the plasmid or present in host cells (COS-1).