title: Construction of a novel porcine circovirus type 2 infectious clone as a basis for the development of a PCV2 iDNA vaccine.
abstract: Porcine circovirus-associated disease is a highly contagious disease that has significant economic consequences. The disease is prevalent in many countries and regions. To generate a genetic marker strain of PCV2, a Sal I restriction enzyme site was inserted into the PCV2 clone as a genetic marker by applying iDNA infectious clone technology. The iDNA represents plasmids that encode the full-length DNA genome of PCV2 assembled in a pcDNA3.1-based vectors. The mutant PCV2 was rescued by transfecting an infectious clone into PK-15 cells and was characterised by an immunoperoxidase monolayer assay (IPMA). The viral genome could be differentiated from the wild-type parent by PCR and restriction fragment length polymorphism (PCR-RFLP). Kunming mice were inoculated with the PCV2 infectious clone or rescued virus via intranasal and intraperitoneal routes. Seroconversion to PCV2-specific antibody appeared in the majority of mice from the two inoculated groups at 7 days postinoculation (DPI), and the specific antibody level was steady for at least 42 days. Viraemia, beginning at 7 DPI and lasting 4 weeks, was detected in the majority of the pigs from the two inoculated groups. The animal experiments revealed that the PCV2 infectious clone and rescued virus both could replicate in mice and induce mice to generate anti-PCV2 antibodies. The infectious clones of PCV2 will be useful for further research investigating a potential tractable iDNA vaccine by reverse genetics technology for attenuated virulance.
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China. Electronic address: weichengwangvet@126.com.
authors.forename: Wei-Cheng
authors.initials: WC
authors.lastname: Wang
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China; Key Laboratory of Animal Epidemic Disease and Veterinary Public Health in Guizhou Province, Guiyang 550025, China. Electronic address: as.zyzeng@gzu.edu.cn.
authors.forename: Zhi-Yong
authors.initials: ZY
authors.lastname: Zeng
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China.
authors.forename: De-Yuan
authors.initials: DY
authors.lastname: Tang
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China.
authors.forename: Hai-Ying
authors.initials: HY
authors.lastname: Liang
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Liu
authors.affiliation: College of Animal Sciences, Guizhou University, Guiyang 550025, China.
authors.forename: Zhen-Jiang
authors.initials: ZJ
authors.lastname: Dai
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D002460:Cell Line; D017925:Circovirus / Q000235:genetics / Q000276:immunology* / Q000502:physiology*; D055808:Drug Discovery / Q000379:methods; D005260:Female; D005822:Genetic Vectors; D007274:Injections, Intraperitoneal; D007275:Injections, Intravenous; D051379:Mice; D010957:Plasmids; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D059386:Reverse Genetics / Q000379:methods*; D013552:Swine; D014162:Transfection; D022581:Vaccines, Marker / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification; D014779:Virus Replication
chemical_list: D000914:Antibodies, Viral; D022581:Vaccines, Marker; D014765:Viral Vaccines
keywords: Genetic marker strain; Infectious clone; Mutant PCV2; Porcine circovirus type 2; iDNA vaccine