African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5233

Full Length Research Paper

Immunogenicity of envelope GP5 protein displayed on baculovirus and protective efficacy against virulent porcine reproductive and respiratory syndrome virus challenge in piglets

Zhisheng Wang1a, Xingang Xu1a, Hungjen Liu2, Zhaocai Li1, Li Ding1, Gaoshui Yu1, Dan Xu1 and Dewen Tong1*
1College of Veterinary Medicine, Northwest A and F University, Yangling, Shaanxi 712100, P.R. China. 2Institute of Molecular Biology, National Chung Hsing University, Taichung 402, Taiwan.
Email: [email protected]

  •  Accepted: 30 July 2011
  •  Published: 16 September 2011

Abstract

In the present study, one recombinant baculovirus BacSC-GP5, expressing His6-tagged GP5 with the transmembrane domain (TM) and cytoplasmic domain (CTD) derived from baculovirus envelope protein gp64, was constructed and its immunogenicity andprotective efficiency was evaluated in piglets. The results obtained show that, His6-tagged recombinant GP5 was expressed and anchored on the plasma membrane of Sf-9 cells, as revealed by Western blot and confocal microscopy. Immunogold electron microscopy demonstrated that, the GP5 glycoprotein was displayed successfully on the viral surface.Piglets immunized with BacSC-GP5 induced successfully GP5-specific enzyme-linked immunosorbent assay (ELISA) antibody, neutralizing antibody and lymphocyte proliferation response at 6 weeks after primary immunization. An in vivo challenge result indicated that piglets immunized with BacSC-GP5 did not show any obvious clinical signs and histological changes, and the quantitative real-time polymerase chain reaction (RT-PCR) also indicated that the porcine reproductive and respiratory syndrome virus (PRRSV) viral load from the serum in BacSC-GP5 group was significantly reduced at 14 and 21 days post-challenge compared to that in the negative control group. These results indicate that baculovirus-mediated gene delivery can be utilized as an alternative strategy to develop a new generation of vaccine against PRRSV infection.

 

Key words: Baculovirus surface display, porcine reproductive and respiratory syndrome virus (PRRSV), GP5 protein, immunogenicity, protective efficacy.