Figure 2.

Comparison of the induction of P18–89.6R10- and P18-I10-specific CTL responses in the SP of mice with preexisting immunity to vaccinia after either IR or IN reimmunization with recombinant viruses. (a) BALB/c mice were immunized s.c. with vSC8 vaccinia virus at 5 × 10⁷ pfu. One month later the mice were reimmunized IN with either recombinant vaccinia vPE16 or MVA89.6 at 1 × 10⁸ pfu. Three weeks later the induction of P18–89.6R10- and P18-I10-specific CTL responses were studied in the SP. The percent specific ⁵¹Cr release was calculated as described in Materials and Methods. E:T, effector-to-target ratio. (b and c) Induction of the systemic HIV-specific CTL responses by different routes of reimmunization of mice with 5 × 10⁷ pfu MVA89.6 (b) or vPE16 (c). Results are means of five mice per group tested individually. Killing of peptide-pulsed targets is compared with killing of unpulsed targets at an E/T of 50:1. Similar results were obtained at ratios of 25 and 12.5:1. In a–c, SEM of triplicate cultures were all <5% of the mean.