Construction and Evaluation of Recombinant Lactococcus lactis Expressing the vscO Gene as a Safe Live Oral Vaccine against Vibrio alginolyticus

Vibrio alginolyticus is responsible for significant economic losses in the fish industry. It urgent to develop a vaccine against V. alginolyticus. In this study, recombinant Lactococcus lactis expressing VscO protein of (Lc-pMG36e-vscO) constructed. The Lc-pMG36e-vscO has good hereditary stability. immune responses pearl gentian grouper (Epinephelus fuscoguttatus (♀) × E. lanceolatu (♂)) vaccinated with are evaluated. titers specific antibody immunized displayed an upward and then downward tendency during total experiments reached peak value 9.6 at fourth week after booster immunization. expression levels IL-1β, IL-16, TNF-α, MHC-1α gene group were significantly upregulated vaccination, indicating that could induce effective durable response. vivo challenge Lc-pMG36e-vscO-immunized showed relative survival percentage 68%. These results indicated be promising as candidate oral