Figure 1. HSV-2ΔgD-2 provides complete protection following intravaginal or skin challenge with vaccine doses as low as 5 × 104 PFU.
C57BL/6 mice were primed and, 21 days later, were boosted s.c. with 5 × 104 PFU, 5 × 105 PFU, or 5 × 106 PFU of HSV-2 ΔgD-2 or VD60 lysates (control). Mice were subsequently challenged 21 days after boost with an LD90 of HSV-2(4674) either (A) intravaginally or (B) via skin scarification and followed for survival (n = 5 mice/group). (C) Serum was assessed for HSV-2 antibodies by ELISA before (PreBleed), day 7 after prime, and day 7 after boost; each symbol represents optical densitometry units (OD) for an individual mouse (n = 5/group); lines represent mean of each group. ΔgD-2– and control-vaccinated groups were compared for survival by Kaplan-Meier and for Ab responses by 2-way ANOVA; **P < 0.01, ***P < 0.001.