title: Mutual enhancement of IL-2 and IL-7 on DNA vaccine immunogenicity mainly involves regulations on their receptor expression and receptor-expressing lymphocyte generation.
abstract: Our previous study showed that IL-2 and IL-7 could mutually enhance the immunogenicity of canine parvovirus VP2 DNA vaccine, although the underlying mechanism remained unknown. Here, we used the OVA gene as a DNA vaccine in a mouse model to test their enhancement on DNA vaccine immunogenicity and to explore the molecular mechanism. Results showed that both IL-2 and IL-7 genes significantly increased the immunogenicity of OVA DNA vaccine in mice. Co-administration of IL-2 and IL-7 genes with OVA DNA significantly increased OVA-specific antibody titers, T cell proliferation and IFN-γ production compared with IL-2 or IL-7 alone, confirming that IL-2 and IL-7 mutually enhanced DNA vaccine immunogenicity. Mechanistically, we have shown that IL-2 significantly stimulated generation of IL-7 receptor-expressing lymphocytes, and that IL-7 significantly induced IL-2 receptor expression. These results contribute to an explanation of the mechanism of the mutual effects of IL-2 and IL-7 on enhancing DNA vaccine immunogenicity and provided a basis for further investigation on their mutual effects on adjuvant activity and immune regulation.
authors.affiliation: Laboratory of Molecular Virology and Immunology, College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, China.
authors.forename: Yonghong
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Medicine, School of Medicine, University of California San Diego, La Jolla, San Diego, CA 92093, USA.
authors.forename: Shuang
authors.initials: S
authors.lastname: Liang
authors.affiliation: Department of Biotechnology, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
authors.forename: Xiujin
authors.initials: X
authors.lastname: Li
authors.affiliation: Laboratory of Molecular Virology and Immunology, College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, China.
authors.forename: Liyue
authors.initials: L
authors.lastname: Wang
authors.affiliation: Laboratory of Molecular Virology and Immunology, College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, China.
authors.forename: Jianlou
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Biotechnology, College of Environmental and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Xu
authors.affiliation: Laboratory of Molecular Virology and Immunology, College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Huo
authors.affiliation: Department of Cardiology, 252 Hospital of Chinese PLA, Baoding 071000, Hebei, China.
authors.forename: Xuebin
authors.initials: X
authors.lastname: Cao
authors.affiliation: Department of Pharmacology, School of Medicine, University of California San Diego, La Jolla, San Diego, CA 92093, USA. Electronic address: z8zhong@ucsd.edu.
authors.forename: Zhenyu
authors.initials: Z
authors.lastname: Zhong
authors.affiliation: Laboratory of Molecular Virology and Immunology, College of Veterinary Medicine, Agricultural University of Hebei, Hebei Engineering and Technology Research Center of Veterinary Biotechnology, Baoding 071000, China. Electronic address: zhongf@hebau.edu.cn.
authors.forename: Fei
authors.initials: F
authors.lastname: Zhong
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000378:metabolism*; D000818:Animals; D000906:Antibodies / Q000097:blood; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000008:administration & dosage / Q000378:metabolism*; D015851:Interleukin-7 / Q000008:administration & dosage / Q000378:metabolism*; D008807:Mice, Inbred BALB C; D010047:Ovalbumin / Q000008:administration & dosage / Q000276:immunology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology*; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000906:Antibodies; D007376:Interleukin-2; D015851:Interleukin-7; D019444:Vaccines, DNA; D007371:Interferon-gamma; D010047:Ovalbumin
keywords: DNA vaccine; Interleukin-2; Interleukin-7; Mutual effects