Co-Expression of Chicken IL-2 and IL-7 Enhances the Immunogenicity and Protective Efficacy of a VP2-Expressing DNA Vaccine against IBDV in Chickens
Shanshan Huo,
Jianlou Zhang,
Jinghui Fan,
Xing Wang,
Fengyang Wu,
Yuzhu Zuo,
Fei Zhong
Affiliations
Shanshan Huo
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Jianlou Zhang
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Jinghui Fan
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Xing Wang
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Fengyang Wu
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Yuzhu Zuo
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Fei Zhong
Laboratory of Molecular Virology and Immunology, College of Animal Science and Technology/College of Veterinary Medicine, Hebei Agricultural University; Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, Hebei, China
Chicken infectious bursal disease (IBD) is still incompletely controlled worldwide. Although IBD virus (IBDV) VP2 DNA vaccine was considered a safe vaccine for IBD prevention, the immunogenicity by itself remains poor, resulting in the failure of effectively protecting chickens from infection. We and others demonstrated that chicken IL-2 (chIL-2) and chIL-7 have the capacity to enhance the immunogenicity of the VP2 DNA vaccine. However, whether chIL-2 and chIL-7 can mutually enhance the immunogenicity of VP2 DNA vaccine and thereby augment the latter’s protection efficacy remains unknown. By using chIL-2/chIL-7 bicistronic gene vector to co-immunize the chickens together with the VP2 DNA vaccine, we now show that chIL-2 and chIL-7 significantly increased IBDV VP2-specific antibody titers, T cell proliferation, and IFN-γ production, resulting in the ultimate enhancement of vaccine-induced protection efficacy relative to that of chIL-2 or chIL-7 gene vectors alone. These results suggest that chIL-2 and chIL-7 can mutually enhance VP2 DNA vaccine’s efficacy, thereby establishing a concrete foundation for future optimization of IBDV VP2 DNA vaccine to prevent/treat chicken IBD.
