FIG 8.

Luminescence expression for 100 BHK-21 PFU of stock and animal-passaged viruses derived from brain tissue. For SINV (A) or EEEV (B) viruses, BHK-21 cells were infected with dilutions of either stock virus (open bars) or viruses harvested from brain at early (hatched bars) or late (solid bars) times p.i. as indicated, and the luminescence derived from 100 BHK PFU was measured at 8 h p.i. The limit of detection of the assay was between 1 and 10 RLU/μg of protein. *, not done due to absence of infectious virus in tissue. Error bars indicate standard deviations.