| abstract |
The present invention provides a novel infectious cDNA clone of porcine reproductive and respiratory syndrome virus (PRRSV), particularly for PRRSV strain VR2385; an improved DNA-launched reverse genetics system for PRRSV; infectious chimeric PRRSV viruses generated through DNA shuffling; modified live- attenuated virus vaccines (MLV) using DNA shuffled chimeric viruses; chimeric viral proteins produced through shuffled chimeric viruses; PRRSV antigens and subunit vaccines based on shuffled chimeric viral proteins; and method of producing broadly protective PRRSV vaccines using DNA shuffling techniques. Particularly, the present invention provides infectious chimeric viruses generated by DNA shuffling of the GP5 genes of genetically distinct strains of PRRSV; modified live-attenuated vaccines comprise infectious chimeric viruses containing the shuffled GP5 genes and/or other shuffled PRRSV proteins (such as GP2, GP3, GP4, M, and non- structural proteins); broadly -protective subunit vaccines comprising PRRSV chimeric shuffled GP5 protein and/or other shuffled PRRSV proteins (such as GP2, GP3, GP4, M, and non- structural proteins). |