Mixed Infection of African Green Monkey Kidney Cells by Adenovirus 7 and SV 40

IT has been shown that mixed infection with adenovirus 12 and SV 40 can occur in African green monkey kidney cells (AGMK) 1 ; moreover, the double infection results in an enhancement of adenovirus growth 2 . In both the foregoing investigations it was demonstrated with electron microscopy that less than 1 per cent of the cells contained adenovirus 12 particles 72 h after infection with adenovirus alone, yet with adenovirus plus SV 40, 75 per cent of the cells contained adenovirus. Determinations of adenovirus infectivity in human embryonic kidney cell cultures using limiting dilution titrations also consistently demonstrated enhancement of adenovirus growth by SV 40. Similar results were obtained with adenovirus 5 by infectivity titrations and electron microscopy.