FIG 7.

Intravaginal versus intramuscular immunization of HSV-2-infected guinea pigs with RR2 protein. (A) Timeline of HSV-2 infection, intravaginal (IVAG) and intramuscular (IM) immunization, and immunological and virological analyses. Guinea pigs (n = 30) were infected intravaginally with 5 × 10⁵ PFU of HSV-2 (MS strain). Once acute infection was resolved, latently infected animals were randomly divided into four groups (n = 10) and then vaccinated with the RR2 protein emulsified in alum plus CpG adjuvant either IVAG or IM on days 15 and 25. Replication-defective HSV-2 dl5-29 mutant vaccine delivered IVAG was used as a positive control. Mock-vaccinated guinea pigs, which received IVAG alum plus CpG adjuvants alone, were used as a negative control. (B) Representative images of genital lesions in guinea pigs vaccinated with RR2 protein either IVAG or IM are shown, along with representative images of dl5-29-vaccinated and mock-vaccinated animals. (C) Cumulative vaginal lesions (left panel) and cumulative positive days with recurrences (right) following IVAG versus IM vaccinations. (D) HSV-2 DNA copy numbers detected in DRG on day 80 p.i. following vaccination by either the IVAG or IM route are shown. (E) Representative FACS data (left panels) and average frequencies and numbers (right panels) of CD4⁺ T cells and CD8⁺ T cells in guinea pigs vaccinated with RR2 protein IVAG or IM are shown. (F) Representative FACS data (left plots) and average frequencies and numbers (right graphs) of IFN-γ⁺ CD4⁺ T cells and IFN-γ⁺ CD8⁺ T cells vaccinated IVAG or IM. The indicated P values show statistical significance between the groups of animals vaccinated IVAG versus IM. *, P < 0.05 (considered significant).