title: Enhanced immune responses in pigs by DNA vaccine coexpressing GP3 and GP5 of European type porcine reproductive and respiratory syndrome virus.
abstract: The European (EU) type of porcine reproductive and respiratory syndrome virus (PRRSV) has recently emerged in China. In this study, three recombinant DNA vaccines, pVAX1-EU-ORF3-ORF5 (coexpressing EU type PRRSV GP3 and GP5), pVAX1-EU-ORF3 and pVAX1-EU-ORF5, were constructed and evaluated for their abilities to induce humoral and cellular responses as well as to protect piglets against homologous virus challenge. All piglets were given booster vaccinations at 21 days after the initial inoculation and then challenged 14 days later. Pigs inoculated with pVAX1-EU-ORF3-ORF5 developed significantly higher (P<0.05) PRRSV-specific antibody responses, neutralizing antibodies and levels of IL-4 and IL-10 than those given pVAX1-EU-ORF3, pVAX1-EU-ORF5 or pVAX1. Moreover, pigs immunized with pVAX1-EU-ORF3-ORF5 had markedly increased levels of IFN-γ and IL-2 in serum and T-lymphocytes (CD3(+)CD4(+) and CD3(+)CD8(+) T cells) in peripheral blood. Thus, EU-type PRRSV GP3 and GP5 proteins demonstrated good immunogenicity and reactogenicity and could induce cellular immunity in pigs. Following challenge with the Lelystad virus (LV) strain, piglets inoculated with pVAX1-EU-ORF3-ORF5 showed viremia and virus load distributed in organ tissues that were significantly lower (P<0.05) than those in the pVAX1-EU-ORF3 group and control group, and slightly lower than those in the pVAX1-EU-ORF5 group (P>0.05). As GP3 could enhance humoral- and cell-mediated immune responses to GP5, the results of this study suggested that these two proteins delivered by a vaccine can synergistically induce immunity against PRRSV.
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun 130062, China; Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: rjq207@163.com.
authors.forename: Jingqiang
authors.initials: J
authors.lastname: Ren
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: nakata0007@sina.com.
authors.forename: Huijun
authors.initials: H
authors.lastname: Lu
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: wen0516@126.com.
authors.forename: Shubo
authors.initials: S
authors.lastname: Wen
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: sunwenchao131@163.com.
authors.forename: Wenchao
authors.initials: W
authors.lastname: Sun
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: yanfulong.xbmu@163.com.
authors.forename: Fulong
authors.initials: F
authors.lastname: Yan
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: chenxing6067@126.com.
authors.forename: Xing
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun 130062, China; Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: jingjie_0915@163.com.
authors.forename: Jie
authors.initials: J
authors.lastname: Jing
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; Institute of Special Animal and Plant Sciences, Chinese Academy of Agricultural Sciences, Changchun 130122, China. Electronic address: liuhaowinner@126.com.
authors.forename: Hao
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: liucunxia9@163.com.
authors.forename: Cunxia
authors.initials: C
authors.lastname: Liu
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: 2224767289@qq.com.
authors.forename: Fei
authors.initials: F
authors.lastname: Xue
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun 130062, China; Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: nick1103771759@gmail.com.
authors.forename: Pengpeng
authors.initials: P
authors.lastname: Xiao
authors.affiliation: Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China; College of Animal Science and Technology, Jilin Agricultural University, Changchun 130118, China. Electronic address: 253691662@qq.com.
authors.forename: Shu
authors.initials: S
authors.lastname: Xin
authors.affiliation: College of Veterinary Medicine, Jilin University, Changchun 130062, China; Institute of Military Veterinary, Key Laboratory of Jilin Province for Zoonosis Prevention and Control, Academy of Military Medical Sciences, Changchun 130122, China. Electronic address: jinningyi2000@aliyun.com.
authors.forename: Ningyi
authors.initials: N
authors.lastname: Jin
mesh_terms: D000825:Animal Structures / Q000821:virology; D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D002681:China; D016207:Cytokines / Q000097:blood / Q000378:metabolism; D006023:Glycoproteins / Q000235:genetics / Q000276:immunology*; D019318:Porcine Reproductive and Respiratory Syndrome / Q000276:immunology / Q000517:prevention & control*; D019316:Porcine respiratory and reproductive syndrome virus / Q000235:genetics / Q000276:immunology*; D013552:Swine; D013601:T-Lymphocytes / Q000276:immunology; D014611:Vaccination / Q000379:methods*; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D019562:Viral Load; D014764:Viral Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
chemical_list: D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D016207:Cytokines; D006023:Glycoproteins; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic; D014764:Viral Proteins; D014765:Viral Vaccines
keywords: DNA vaccine; European PRRSV; GP3; GP5; Immune responses; Pigs