FIG. 6.

GBV-B produced in the presence of ribavirin has low specific infectivity. Primary tamarin hepatocytes were cultivated with (+) or without (−) 100 μM ribavirin as described in the legend to Fig. 3. Secreted virus was harvested on day 3 or 6 postinfection with GBV-B. The virus levels in the media were adjusted to contain identical genome equivalents based on TaqMan RT-PCR. The media were then used to inoculate fresh cultures of hepatocytes. The infected cultures were harvested 7 days postinoculation, and the level of cell-associated viral RNA (in genome equivalents per microgram of cell RNA) was determined as a measure of specific infectivity of the inoculum. Infectivity of GBV-B harvested after 3 days of ribavirin treatment was decreased 2 log units, while GBV-B harvested after 6 days of ribavirin treatment lacked measurable infectivity. The small bar present for the sample treated with ribavirin for 6 days shows that the sample was tested but no viral RNA was detected. On the left y axis, genome equivalents are shown on a logarithmic scale (1e+0, 10⁰; 1e+1, 10¹; 1e+2, 10², etc.).