Protective immune responses in ducklings induced by a suicidal DNA vaccine of the sigma C gene of novel duck reovirus

• A suicidal DNA vaccine was evaluated for the development of a vaccine against NDRV.
• NDRV-specific antibodies and cell immune response were well induced in ducklings.
• All the ducklings inoculated with the DNA vaccine were protected against NDRV.
• The DNA vaccine is a promising vaccine candidate for prevention of duck reovirus.

A suicidal DNA vaccine based on a Semliki Forest virus (SFV) replicon was evaluated for the development of a vaccine against novel duck reovirus (NDRV). The sigma C gene of NDRV was cloned and inserted into pSCA1, an SFV DNA-based replicon vector. After transfected into BHK-21 cells, the antigenicity of the sigma C protein was confirmed using an indirect immunofluorescence and Western blot assay. Immunogenicity was studied in ducklings. The results showed that NDRV-specific antibodies, neutralizing antibodies, IFN-γ and IL-4 were well induced in ducklings. Furthermore, all of the ducklings were protected against challenge with wild-type NDRV.