Cephas T. Patch

The Adenovirus-SV40 Hybrid Viruses

The adenovirus-simian virus 40 (Ad-SV40) hybrid viruses are stable viral recombinants which form in monkey kidney cells (MKC) coinfected with the simian papovavirus SV40 and a number of human adenovirus serotypes. The genomes of these viruses are composed mainly of Ad DNA (integrated with varying amounts of SV40 DNA) and are enclosed in capsids whose morphological and immunological properties are indistinguishable from those of the parent nonhybrid adenovirus. Studies of the Ad-SV40 hybrid viruses have made important contributions to a number of areas of molecular virology; previous reviews of these studies include those by Rapp (1973) and Lewis (1977).

Kinetics of inhibition of papovavirus DNA synthesis by superinfection with adenovirus 2 and non-defective adenovirus 2-simian virus 40 hybrid viruses.

Simian Virus 40 (SV40) DNA synthesis is inhibited in monkey cells by superinfection with adenovirus 2 (Ad2) and various non-defective Ad2-SV40 hybrid viruses. Similarly, BKV (a human papovavirus) DNA synthesis is inhibited in human cells by superinfection with Ad2. Kinetic studies indicate that inhibition begins during the early phase of the Ad2 lytic cycle. Superinfection with Ad2 does not significantly alter the formation of SV40 T antigen. Superinfection with Ad2 late in SV40 lytic cycle is less efficient in the inhibition of SV40 DNA synthesis, and the onset of Ad2 DNA synthesis is delayed, compared to superinfection early in the SV40 lytic cycle. These findings suggest that the Ad2 and SV40 genomes may compete to bind an early AD2 protein which is essential for Ad2 replication, but which blocks SV40 replication.