Immunization with OMVs reduced bacterial burden in a pneumonia model.
(A) The bacterial loads in BALF, lung and spleen were detected continuously for 9 days in the pneumonia model. The A. baumannii group was challenged with A. baumannii, and the control group received no challenge; (B) The mice that were actively vaccinated with OMVs showed a significant reduction in bacterial loads; (C) The mice that received passive immunization with the antisera were completely protected from A. baumannii infection. The p value was determined by an unpaired Student's t test. *, p<0.05, **, p<0.01, ***, p<0.001; n = 12 mice per group.