FIG. 3.
CTL memory upon vaginal infection with Flu/P18IIIB virus. Mice were vaginally infected with 3 × 105 PFU of Flu/P18IIIB virus and infected with 2 × 107 PFU of vaccinia vPE16 virus 5 months later. Naive (unimmunized) mice were also infected with vPE16 and served as a control representing the magnitude of a primary response. ILNs (A) and spleens (B) were removed at day 3 or 5 after vaginal vPE16 infection. The ILNs were cultured without antigen stimulation for 3 days before being tested in a CTL assay. Spleen cells were stimulated for 6 days in vitro with irradiated P18-I10 peptide-loaded stimulators before being examined for CTL activity. CTLs were assayed with P18-I10 peptide-pulsed P815 cells used as targets. Mean lysis values (± standard deviation) measured at an E:T ratio of 50:1 are shown.