Effect of Stat 1 on innate resistance to HSV-1. Wild-type (strain 129) mice, rag2-/- mice, stat1-/- mice, and rag2-/-stat1-/- mice were inoculated with 2 × 105 pfu/eye of HSV-1 strain KOS-GFP. A. Eyes of KOS-GFP-infected mice on days 1, 2, 3, and 4 p.i (4× magnification, illuminated with 360–400 nm light which excites GFP). A representative mouse from each group was sequentially imaged on days 1 through 4 p.i. B. Replication of HSV-1 strain KOS-GFP in the eyes of mice (mean ± SEM; n= 6; dashed line denotes lower limit of detection). Asterisks denote times at which stat1-/- mice shed more virus than stat1+/+ mice (p < 0.05, ANOVA and Tukey's post hoc t-test). C. Duration of survival of HSV-1 infected mice (n = 6 per group).