Figure 4.

There is active lytic viral replication at Day 7 after murine gammaherpesvirus-68 (γHV68) infection, and previous fibrotic insult leads to increased viral load. Wild-type mice were given either saline or fluorescein isothiocyanate (FITC) intratracheally on Day 0. On Day 14, they were given γHV68 (5 × 10⁴ pfu) intranasally. Lungs were harvested on Day 21. (A) Viral plaque assay demonstrates that there is active viral replication at Day 7 postinfection, and mice given FITC are more susceptible to the γHV68 infection (n = 5, P = 0.04). (B) Real-time polymerase chain reaction demonstrates increased lytic viral gene expression in FITC-treated lungs at Day 7 postinfection. Viral gene expression of mice given virus post-saline (open bars) was set at 1 and gene expression of mice given FITC and virus (solid bars) is expressed in comparison. Viral gene expression of both genes is increased approximately 3.5-fold in mice that were given FITC before infection (n = 3). DNApol = DNA polymerase; gB = glycoprotein B.