Construction and immunogenicity of recombinant pseudotype baculovirus expressing the capsid protein of porcine circovirus type 2 in mice

J Virol Methods. 2008 Jun;150(1-2):21-6. doi: 10.1016/j.jviromet.2008.02.011. Epub 2008 Apr 3.

Abstract

Baculovirus has emerged recently as a novel and attractive gene delivery vehicle for mammalian cells. Porcine circovirus type 2 (PCV2) is known to be associated with post-weaning multisystemic wasting syndrome (PMWS), an emerging swine disease which results in tremendous economic losses. In this study, baculovirus pseudotyped with vesicular stomatitis virus glycoprotein (VSV-G) was used as a vector to express capsid (Cap) protein, the most important immunogen of PCV2, under the transcriptional control of cytomegalovirus immediate early (CMV-IE) enhancer/promoter. The resultant recombinant baculovirus (BV-G-ORF2) efficiently transduced and expressed the Cap protein in mammalian cells, as demonstrated by Western blot and flow cytometric analyses. After direct vaccination with 1x10(8) or 1x10(9)plaque forming units (PFU)/mouse of BV-G-ORF2, significant PCV2-specific ELISA antibodies, neutralizing antibodies, as well as cellular immune responses could be induced in mice. BV-G-ORF2 exhibited better immunogenicity than a DNA vaccine encoding the Cap protein, even at a dose of 1x10(8)PFU/mouse. Taken together, the improved immunogenicity of BV-G-ORF2, together with the unique advantages of pseudotype baculovirus, including easy manipulation, simple scale-up, lack of toxicity, and no pre-existing antibody against baculovirus in the hosts, indicate that pseudotype baculovirus-mediated gene delivery can be utilized as an alternative strategy to develop a new generation of vaccines against PCV2 infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Baculoviridae / genetics*
  • Capsid Proteins / genetics
  • Capsid Proteins / immunology*
  • Circovirus / genetics
  • Circovirus / immunology*
  • Cytomegalovirus / genetics
  • Female
  • Gene Expression
  • Genetic Vectors*
  • Mice
  • Mice, Inbred BALB C
  • Neutralization Tests
  • Porcine Postweaning Multisystemic Wasting Syndrome / prevention & control*
  • Promoter Regions, Genetic
  • Swine
  • T-Lymphocytes / immunology
  • Transduction, Genetic
  • Vesicular stomatitis Indiana virus / genetics
  • Viral Vaccines / genetics
  • Viral Vaccines / immunology*

Substances

  • Antibodies, Viral
  • Capsid Proteins
  • Viral Vaccines