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<div><p>Outer membrane vesicles (OMVs) are immunogenic self-adjuvanting vesicles produced by Gram-negative bacteria such as <i>Pseudomonas aeruginosa</i> and <i>Yersinia pseudotuberculosis</i>. While the effects of OMVs on different antigens immune stimulation are not clear. In this study, we constructed recombinant <i>Yersinia pseudotuberculosis ΔlpxL</i> strain,with <i>pBlue-PcrV</i> and <i>pBlue-OprF/I</i>, and then purified <i>ΔlpxL</i> rOMV<sub>PcrV</sub> (rOMVyp2P)and <i>ΔlpxL</i> rOMV<sub>OprF/I</sub> (rOMVyp2F) and analyzed its effect on immune response and protection against <i>Pseudomonas aeruginosa</i> PAO1 infection. The results showed that OMV assists in eliciting similar humoral immune responses to PcrV and OprF/I antigens. <i>ΔlpxL</i> rOMV<sub>PcrV</sub> and <i>ΔlpxL</i> rOMV<sub>OprF/I</sub> elicited Th1/Th2 balanced immune response, and higher IgM and IgA antibodies.However, there are differences in immune protection for the pulmonary. The survival rate of mice in <i>ΔlpxL</i> rOMV<sub>PcrV</sub> group was 20%, which was significantly better than that in <i>ΔlpxL</i> rOMV<sub>OprF/I</sub> group. <i>ΔlpxL</i> OMV<sub>PcrV</sub> is better cooperation for <i>Pseudomonas</i> immune protection in lung.</p></div>