Figure 4. Effects of active immunoprotection with the 6pGST FbsA fragment in adult and neonatal mouse models of GBS sepsis.

A. Immunoprotection in adult mice. Five-week-old CD1 mice underwent three immunizations with the 6p FbsA fragment fused to GST (6pGST) or with GST alone. At 3 weeks after the last immunizations mice were challenged by the i.p. injection of GBS strain COH1 (5x10⁷ CFUs) and lethality was observed daily. *, p<0.05 relative to GST-immunized mice by Kaplan-Meier survival plots. Shown are the cumulative results of two independent experiments. B. Effect of maternal immunization on survival of experimentally infected pups. Female CD1 mice (5 wk old) were immunized three times with the 6p FbsA fragment fused to GST (6pGST) or with GST alone. Mice were then time-mated and two-day-old pups were infected s.c. with 250 CFUs of GBS strain 6313. *, p<0.05 relative to GST-immunized mice by Kaplan-Meier survival plots.