Potential Usefulness of Streptococcus pneumoniae Extracellular Membrane Vesicles as Antibacterial Vaccines

Figure 3

Survival of vaccinated mice after infection with Streptococcus pneumoniae. Mice (8 weeks old) were vaccinated intraperitoneally with S. pneumoniae BAA-255 extracellular membrane vesicles. After intraperitoneal inoculation with 1 × 10⁸ cfu of nonpathogenic S. pneumoniae BAA-255 or 1 × 10³ cfu of pathogenic S. pneumoniae KCCM-41569, survival over 7 days was assessed. Equivalent volumes of phosphate-buffered saline served as a vaccine control.

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