Protective immunity conferred by porcine circovirus 2 ORF2-based DNA vaccine in mice.
Post-weaning multisystemic wasting syndrome (PMWS) associated with porcine circovirus type 2 (PCV2) has caused the swine industry significant health challenges and economic damage. Although inactivated and subunit vaccines against PMWS have been used widely, so far no DNA vaccine is available. In this study, with the aim of exploring a new route for developing a vaccine against PCV2, the immunogenicity of a DNA vaccine was evaluated in mice. The pEGFP-N1 vector was used to construct a PCV2 Cap gene recombinant vaccine. To assess the immunogenicity of pEGFP-Cap, 80 BALB/c mice were immunized three times at 2 weekly intervals with pEGFP-Cap, LG-strain vaccine, pEGFP-N1 vector or PBS and then challenged with PCV2. IgG and cytokines were assessed by indirect ELISA and ELISA, respectively. Specimens stained with hematoxylin and eosin (HE) and immunohistochemistry (IHC) techniques were examined histopathologically. It was found that vaccination of the mice with the pEGFP-Cap induced solid protection against PCV2 infection through induction of highly specific serum IgG antibodies and cytokines (IFN-γ and IL-10), and a small PCV2 viral load. The mice treated with the pEGFP-Cap and LG-strain developed no histopathologically detectable lesions (HE stain) and IHC techniques revealed only a few positive cells. Thus, this study demonstrated that recombinant pEGFP-Cap substantially alleviates PCV2 infection in mice and provides evidence that a DNA vaccine could be an alternative to PCV2 vaccines against PMWS.
Laboratory of Infectious Disease, College of Veterinary Medicine, Jilin University, Xi'an Road 5333, Changchun, Jilin, 130062, China; Institut Supérieur des Sciences et de Médecine Vétérinaire, Dalaba 09, Guinea.
Seydou
S
Sylla
Yan-Long
YL
Cong
Yi-Xue
YX
Sun
Gui-Lian
GL
Yang
Xue-Mei
XM
Ding
Zhan-Qing
ZQ
Yang
Yu-Long
YL
Zhou
Minnan
M
Yang
Chun-Feng
CF
Wang
Zhuang
Z
Ding
D000818:Animals; D057134:Antibodies, Neutralizing / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000235:genetics / Q000276:immunology; D018173:Circoviridae Infections / Q000473:pathology / Q000517:prevention & control* / Q000821:virology; D017925:Circovirus / Q000235:genetics* / Q000276:immunology*; D016207:Cytokines / Q000097:blood; D015870:Gene Expression; D023061:Gene Order; D056724:Immunity, Humoral; D007150:Immunohistochemistry; D008198:Lymph Nodes / Q000378:metabolism / Q000473:pathology; D051379:Mice; D010957:Plasmids / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics; D013552:Swine; D019444:Vaccines, DNA / Q000276:immunology*; D019562:Viral Load; D014765:Viral Vaccines / Q000276:immunology*
D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D036022:Capsid Proteins; D016207:Cytokines; D011993:Recombinant Fusion Proteins; D019444:Vaccines, DNA; D014765:Viral Vaccines
Capsid protein; DNA vaccine; porcine circovirus type 2