Influence of 12-O-tetradecanoylphorbol 13-acetate on replication of porcine cytomegalovirus in the 19-PFT-F cell line

Severe cytopathic effects, formation of swollen cells and small syncitia, appeared in 19-PFT-F cell cultures at 2 days when a large amount of the OF1 strain of porcine cytomegalovirus (PCMV) was inoculated and cultured in media containing 5, 10, 30 and 60 ng per ml of 12-O-tetradecanoylphorbol 13-acetate (TPA). Characteristic focal clusters of swollen cells appeared on the 19-PFT-F monolayers 3 to 4 days after inoculation with a small amount of the virus. Cells in the foci contained specific fluorescent antigens in the nucleus and cytoplasm. The infectivity could be determined for 4 days after inoculation by means of measuring focus formation in the presence of medium containing TPA. The virus replicated more rapidly in the medium with, rather than without, TPA.