FIG. 6.

Protection against HSV-2 latent DNA load in the DRG. On weeks 46 to 48 of the study (28 to 30 weeks postchallenge), the lumbosacral DRG from each surviving guinea pig were removed, pooled, and frozen. The DRG DNA from each pool was extracted and quantified by spectrophotometry. HSV-2 DNA was quantified by TaqMan real-time quantitative PCR using primers and a probe specific for gG2. Each reaction mixture contained 250 ng of DRG DNA, and each standard curve reaction mixture contained 250 ng of DRG DNA from naïve guinea pigs and between 10 and 10⁴ copies of HSV-2 DNA isolated from purified HSV-2 virions. Each symbol represents the mean of 3 independent assays for an individual (Indiv.) guinea pig, and the horizontal lines represent vaccine group means. Two additional control groups consisted of the DRG from 4 naïve guinea pigs (Naïve) and from 3 guinea pigs that were immunized with FI-HSV2 but were not challenged with HSV-2 (FI-HSV2 Unchallenged). The broken line represents the detection limit of the assay of 10 copies of HSV-2 DNA per 250 ng of DRG DNA. Statistical significance levels for the values for each group compared with the pVAX-FI-Mock group are as described in the legend to Fig. 3.