Protection from HSV-2-induced disease requires viable chlamydiae.

<p>(A) Mice were super-infected with 10⁶ UV-irradiated Cm (UVCm) then with 5 x 10³ PFU HSV-2 on day 3 pci (UVCm-3D-H). As controls, mice were singly-infected with UV-irradiated Cm (UVCm) on day 0 or with HSV-2 on day 3 pci (HSV-2). Vaginal swabbing was performed every 3 days until day 21 pci. (B) Morbidity and mortality resulting from HSV-2 was monitored daily and the percent survival between experimental groups was compared using the log rank statistic. Significant (p<0.05) difference from Cm singly-infected control is indicated by an asterisk (*). The survival curve depicts data combined from 3 separate experiments with n = 24 for UVCm and n = 36 for both the HSV-2 and UVCm-3D-H groups. Note that 100% survival was also observed in mock, Cm, and super-infected Cm-3D-H control groups that were included within this experiment (not shown). (C) Chlamydial shedding was determined by chlamydial titer assay and is reported as average IFU/mouse +/- SEM. (D) Average chlamydial shedding at day 3 pci (indicated by bars) and individual mouse chlamydial shedding (segregated according to survival status) are shown; n = 8 for Cm (circles), and n = 12 for both Cm-3D-H (diamonds) and UVCm-3D-H (triangles). (E) HSV-2 recovery was determined by plaque assay and is reported as average PFU/mouse +/- SEM. (F) Average HSV-2 recovery at day 6 pci (indicated by bars) and individual mouse HSV-2 recovery (segregated according to survival status) are shown; n = 8 for HSV-2 (circles) and n = 12 for UVCm-3D-H (triangles). Survivors and non-survivors are indicated by S and NS, respectively. Differences in pathogen shedding/recovery between groups in panels C-F were determined with the paired Student’s t-test with p<0.05 considered significant and are representative of 3 independent experiments.