FIG. 1.

Dipyridamole and virus yield. HeLa cell monolayers were infected at a multiplicity of 50 PFU/cell. Dipyridamole-treated samples (DPM+) had 80 μM dipyridamole (in ethanol) added to the medium at the time of infection. Dipyridamole-untreated samples (DPM−) were dosed with an equivalent volume of ethanol. (A) Medium from dipyridamole-treated cultures was exchanged with drug-free medium at the indicated times. Virus was harvested at 8 h postinfection and the titer was determined by plaque assay. (B) Medium from dipyridamole-untreated cultures was exchanged with medium containing dipyridamole (80 μM) at the indicated times. Virus was harvested at 8 h postinfection and then titered.