Effect of WBC depletion on innate resistance to HSV-1. BALB/c mice and BALB/c scid mice, inoculated with 2 × 105 pfu/eye HSV-1 strain KOS, received i.p. injections of PBS or cyclophosphamide (CyP; 125 mg/kg) on days -1, 1, and 3 p.i. Uninfected BALB/c mice and uninfected scid mice received i.p. injections of CyP at the same time points (n = 8 per group). A. Viral replication in the eyes of BALB/c mice and scid mice treated with PBS or CyP (mean ± SEM; n = 8; dashed line denotes lower limit of detection). Asterisks denote times at which CyP-treated BALB/c mice shed more virus than PBS-treated BALB/c mice (p < 0.05, ANOVA and Tukey's post hoc t-test). B and C. Duration of survival of HSV-1 infected B. BALB/c mice and C. scid mice treated with PBS or CyP versus uninfected, CyP-treated controls (n = 8 per group).