Figure 6.

Pre-incubation of C. trachomatis with immune serum from Qβ-CT584-vaccinated mice reduces infection in the upper genital tract. C. trachomatis were pre-opsonized in vitro with heat-inactivated serum pooled from mice immunized with Qβ-CT584 or Qβ alone, immediately prior to transcervical inoculation into the upper genital tract of naïve female mice. Bacterial burden in the upper genital tract was measured by qPCR. Data are presented from independent pre-opsonization experiments using immune serum from two independent vaccine trials, Trial 1 ((A), p = 0.0159) and Trial 2 ((B), p = 0.095). Pre-incubation with Qβ-CT584 serum resulted in a 83–84% reduction in bacterial burden compared to pre-incubation with negative control Qβ serum. Horizontal lines represent means +/− SEM.