Figure 4.

Protection against a peripheral infection with recombinant vaccinia viruses after immunization with LCMV or recombinant Listeria. BALB/c mice were immunized with 200 pfu of LCMV or 2 × 10³ cfu of Listeria (wt-LM; rLM-NP_actA; rLM-NP_118–126). Eight, sixty, and one hundred and twenty days after primary immunization, mice were challenged with 10⁷ pfu of VaccNP (a) or VaccLL0 (b) i.p., Five days after the challenge infection, vaccinia titers in the ovaries were determined by a plaque-forming assay, and the results of three mice per group are shown. The horizontal dashed line represents the detection limit. One of two similar experiments is shown.