Development and Evaluation of a Trivalent Riemerella anatipestifer-Inactivated Vaccine

Abstract

b Riemerella anatipestifer infections cause major economic losses in the duck industry. In this study, a trivalent inactivated vaccine of R. anatipestifer, including strains CH3 (serotype 1), NJ3 (serotype 2), and HXb2 (serotype 10), was developed. Animal experiments showed that the ducks that received two immunizations with the vaccine were 100% protected from challenge with strains from any of the three serotypes (1, 2, or 10). No death or clinical signs of diarrhea, tremors, or limb swelling were shown in the protected ducks. Also, no R. anatipestifer bacteria were isolated from the livers or brains of the protected ducks. Furthermore, no histopathological changes were observed in the liver, spleen, or brain samples from the protected ducks during histological examination. The ducks that received two immunizations with the vaccine generated high antibody titers of 1:3,200 to 1:6,400 against the three serotypes of strains. The vaccine significantly enhanced the production of gamma interferon (IFN-␥) and interleukin 2 (IL-2) after one immunization and enhanced the production of IL-4 and IL-10 after two immunizations. In addition, real-time PCR indicated that the expression of major histocompatibility complex I (MHC-I), as well as that of CD40 and CD154 molecules, was significantly increased after one immunization, and the expressions of both MHC-I and MHC-II molecules were increased after two immunizations. Our study indicates that the vaccine can induce both humoral and cellular immunities in ducks and offer effective protection against R. anatipestifer infection.

Levamisole enhances immunity in ducklings vaccinated against Riemerella anatipestifer

“…It had been reported that the RA inactivated vaccine can stimulate vaccinated ducks to produce larger amounts of both Th1 and Th2 cytokines , and a similar phenomenon was observed in the present study. The production of IL‐2, IL‐4, and IL‐10 was higher in the oil‐emulsion vaccine group compared with the control group and the addition of LMS to the inactivated vaccine further promoted secretion of both Th1 and Th2 cytokines.…”

The M949_1556 gene plays a role on the bacterial antigenicity and pathogenicity of Riemerella anatipestifer

“…A trivalent R. anatipestifer inactivated vaccine protecting against serotypes 1, 2 and 10 strains has been developed successfully (Liu et al, 2013). We showed in this study that the inactivated-CH3DM949_1556 vaccine was effective in cross-protecting the ducks from challenge with R. anatipestifer strains WJ4 (serotype 1), Yb2 (serotype 2) and HXb2 (serotype 10) at 100%, 75% and 100% respectively, suggesting that the CH3DM949_1556 strain is an effective vaccine candidate to protect ducks against R. anatipestifer infection in China.…”

“…To test the cross-protection, the inactivated CH3DM949_1556 vaccine was prepared and 7-day-old Cherry Valley ducks were immunized as described previously (Liu et al, 2013). Inactivated CH3 vaccine (serotype 1) was used as a control .…”

“…anatipestifer strain CH3 was cultured to logarithmic phase and inactivated with formalin as described (Liu et al, 2013). BALB/c mice were immunized with the inactivated bacterial cells at 1 Â 10 8 colony-forming unit (CFU) for three times.…”

“…Serotypes 1, 2, and 10 are responsible for most of the major R. anatipestifer outbreaks in China (Hu et al, 2010). The chaperonin GroEL was the first reported protein providing a cross-protection among R. anatipestifer serotypes 1, 2 and 10 , although the protection rate is not as high as that of inactivated bacterin (Liu et al, 2013). The mixture of recombinant Riean_1750 and Riean_1752, two proteins identified from R. anatipestifer cultured in iron restricted medium, provided 100% protection against challenge with R. anatipestifer, but no cross-protection was shown (Yang et al, 2013).…”