Author
![]() |
KWANG, J - FORMER ARS EMPLOYEE |
![]() |
ZUCKERMANN, F - UNIVERSITY OF ILLINOIS |
![]() |
Ross, Gary |
![]() |
YANG, S - FORMER ARS EMPLOYEE |
![]() |
OSORIO, FERNANDO - UNIVERSITY OF NEBRASKA |
![]() |
LIU, W - UNIVERSITY OF SINGAPORE |
![]() |
LOW, S - UNIVERSITY OF SINGAPORE |
Submitted to: Research in Veterinary Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 3/20/1999 Publication Date: N/A Citation: N/A Interpretive Summary: The immune response to individual porcine reproductive and respiratory syndrome virus (PRRSV) proteins was determined by DNA vaccination against each of the corresponding viral genes. Results suggest that virus neutralizing antibodies are induced by the ORF 4 and ORF 5 gene products and that detectable antibody and cell-mediated immune responses were elicited to ORFs 4, 5, 6 and 7. These results indicate that DNA immunization is capable of eliciting immune responses to the major structural proteins of PRRSV and that the ORF 4 and ORF 5 gene products are likely vaccine candidates due to the presence of neutralizing epitopes on these proteins. Technical Abstract: The objectives of this study was to investigate the role of DNA vaccines in the generation of an immune response and that elicited against individually encoded proteins of PRRS virus. The genomic regions encoding ORFs 4, 5, 6 and 7 of the PRRS virus vaccine strain were cloned into the mammalian expression vector pcDNA3.1 (+). Inoculations with the recombinant plasmids resulted in detection of PRRS virus-specific antibodies in 71% of the immunized animals by ELISA, virus neutralization and/or Western blotting assays. In addition, cellular immune responses were detected in 86% of the immunized pigs by interferon gamma assay and/or proliferation assay. Pigs in the control group had no detectable immune response to PRRS virus. The results obtained demonstrated that DNA immunization against PRRS virus results in the production of both humoral and cell mediated immune responses in pigs. The results also indicate that neutralization epitopes for PRRS virus are present on the viral envelope glycoproteins encoded by ORF4 and ORF5. |