FIG 2.

HPV PsV expressing secreted gB induce preferentially HSV-specific CD8⁺ T cells in the genital tract. Medroxyprogesterone acetate-treated mice (4 per group) were immunized ivag with 10⁸ IU of HPV16 expressing gBsec, gBcyt, or gBfl, followed 1 month later by an ivag booster immunization with 10⁸ IU of HPV45 expressing the same construct. As a positive control, a group of mice was immunized i.n. twice, 1 month apart, with 20 μg of the minimal immunodominant peptide gB_496–503 admixed with 1 μg CT. As a negative control, a group of mice was immunized with 10⁸ IU of HPV16 expressing luciferase, followed 1 month later by a second immunization with 10⁸ IU of HPV45 expressing luciferase. (A) FACS analysis plots of expression of CD8 and CD4 by cervicovaginal cells and expression of CD3 and the K^b/gB₄₉₆ tetramer by cervicovaginal CD8⁺ T cells. (B to D) Data are expressed as means ± standard errors of the means and are representative of the results of 3 independent experiments. Asterisks indicate significant differences (*, P < 0.05; **, P < 0.01; ***, P < 0.001) by one-way ANOVA and multiple comparisons. (E) Correlation between K^b/gB₄₉₆ tetramer-positive CD8⁺ T cells in blood and K^b/gB₄₉₆ tetramer-positive cervicovaginal CD8⁺ T cells. (F) Tissue sections of the cervicovaginal mucosae of mice immunized with a control HPV vector or with HPV-gBsec were collected 4 weeks after the booster and were stained with anti-CD8 (green) and anti-CD4 (red) antibodies and with DAPI (blue).