FIG. 5.

Inducer dependence of virus yield. Monolayers of BSC-1 cells were infected with virus vA5Li at an MOI of 1 PFU per cell in the presence of 0, 5, 10, 25, 50, or 250 μM IPTG. After 24 h, the monolayers were harvested, the virus was released by three cycles of freezing-thawing, and the titers were determined by plaque assay on BSC-1 monolayers infected in the presence of 25 μM IPTG.