FIG. 7.
Viral growth in the brains of wt and cathepsin-deficient mice following intracranial inoculation. C57BL/6 wt and cathepsin-deficient mice, 2 to 4 days (d) old, were inoculated intracranially with 102 PFU T3SA+. Brains were resected at the times shown and homogenized by freeze-thawing and sonication. Viral titers in brain homogenates were determined by a plaque assay. Results are expressed as mean viral titers in the brains of 9 to 13 mice. Error bars represent standard errors of the means. *, P values of <0.05, as determined by a Mann-Whitney test, in comparison to the level for wt mice at the same time after inoculation. The limit of detection was 102 PFU/brain.