Immunogenicity of a recombinant pseudorabies virus expressing ORF1-ORF2 fusion protein of porcine circovirus type 2

Vet Microbiol. 2005 Aug 30;109(3-4):179-90. doi: 10.1016/j.vetmic.2005.06.001.

Abstract

Porcine circovirus type 2 (PCV2) is associated with post-weaning multisystemic wasting syndrome (PMWS). Pseudorabies (PR) is also an important infectious disease in swine and sometimes co-infect with PCV2. An attenuated pseudorabies virus (PRV) has been successfully used as a vector for live viral vaccines. In this study, a recombinant PRV expressing ORF1-ORF2 fusion protein of PCV2 was constructed and its immunogenicity was tested in mice and pigs. The ORF1 and partial ORF2 gene of PCV2 Yu-A strain were amplified by PCR and inserted into a transfer vector. The recombinant transfer plasmid was co-transfected with the EcoRI digested genome of vector virus (PRV TK-/gE-/LacZ+) into IBRS-2 cells. The recombinant pseudorabies virus PRV-PCV2 was purified by plaque purification and identified by PCR and Southern blotting. Expression of the ORF1-ORF2 fusion protein by the recombinant PRV-PCV2 virus was demonstrated by Western blotting analysis. The growth properties of the recombinant virus in cells were similar to that of the parent vector virus. In animal experiments, PRV-PCV2 elicited strong anti-PRV and anti-PCV2 antibodies in Balb/c mice as indicated by PRV-neutralizing assay, anti-PCV2 ELISA and PCV2 specific lymphocyte proliferation assay, respectively. And PRV-PCV2 immunization protected mice against a lethal challenge of a virulent PRV Ea strain. In pigs, PRV-PCV2 elicited significant immune response towards PRV and PCV2 as indicated by PRV-ELISA, PRV neutralizing assay and PCV2 specific lymphocyte proliferation assay, respectively. This is a first step toward the development of a potential candidate divalent vaccine against PRV and PCV2 infections.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antibodies, Viral / blood
  • Blotting, Western / veterinary
  • Circoviridae Infections / complications
  • Circoviridae Infections / genetics
  • Circoviridae Infections / immunology
  • Circoviridae Infections / prevention & control
  • Circoviridae Infections / veterinary*
  • Circovirus / genetics
  • Circovirus / immunology*
  • DNA, Viral / chemistry
  • DNA, Viral / genetics
  • Enzyme-Linked Immunosorbent Assay / veterinary
  • Female
  • Herpesvirus 1, Suid / genetics
  • Herpesvirus 1, Suid / immunology*
  • Immunization / veterinary
  • Mice
  • Mice, Inbred BALB C
  • Open Reading Frames*
  • Pseudorabies / complications
  • Pseudorabies / genetics
  • Pseudorabies / immunology*
  • Pseudorabies / prevention & control
  • Random Allocation
  • Recombinant Fusion Proteins / genetics
  • Recombinant Fusion Proteins / immunology
  • Swine
  • Swine Diseases / immunology
  • Swine Diseases / prevention & control
  • Swine Diseases / virology*
  • Vaccines, DNA / genetics
  • Vaccines, DNA / immunology
  • Viral Proteins / genetics
  • Viral Proteins / immunology*
  • Viral Vaccines / genetics
  • Viral Vaccines / immunology

Substances

  • Antibodies, Viral
  • DNA, Viral
  • Recombinant Fusion Proteins
  • Vaccines, DNA
  • Viral Proteins
  • Viral Vaccines