Multiple Functions for ORF75c in Murid Herpesvirus-4 Infection
Figure 8
ORF75c disruption impairs host colonization.
A. Mice were infected intranasally (106 genomes each, equivalent to 103 p.f.u. for the wild-type) with ORF75+ (wild-type, revertant.1) or ORF75− (ORF75c−.4, ORF75c−.7) viruses. Lungs were collected 1 or 3 days later and spleens 30 days later. Viral genome loads in 100 ng DNA from each sample was measured by real-time PCR of the M2 locus. Part of the adenosine phosphoribosyl transferasegene was amplified as a cellular control. Each bar shows mean and SEM values for groups of 5 mice. B. Mice were infected intranasally (106 genomes each) with wild-type or ORF75c−.4 viruses. B cell activation in mediastinal lymph nodes was assayed after 6 d by flow cytometry of the CD69 activation marker on CD19+ B cells. Equivalent B cells from naive mice are typically 5%CD69+. After 30 d, virus-driven CD8+Vβ4+ T cell expansion was measured by flow cytometry of spleen cells. Typically 5% of CD8+ splenic T cells are Vβ4+ in uninfected mice. Each bar shows mean and SEM values for 5 individual mice. C. Mice were infected as in A, then analyzed 30 days later for MuHV-4-specific serum IgG by ELISA.