title: Construction of an infectious cDNA clone of genotype 1 avian hepatitis E virus: characterization of its pathogenicity in broiler breeders and demonstration of its utility in studying the role of the hypervariable region in virus replication.
abstract: A full-length infectious cDNA clone of the genotype 1 Korean avian hepatitis E virus (avian HEV) (pT11-aHEV-K) was constructed and its infectivity and pathogenicity were investigated in leghorn male hepatoma (LMH) chicken cells and broiler breeders. We demonstrated that capped RNA transcripts from the pT11-aHEV-K clone were translation competent when transfected into LMH cells and infectious when injected intrahepatically into the livers of chickens. Gross and microscopic pathological lesions underpinned the avian HEV infection and helped characterize its pathogenicity in broiler breeder chickens. The avian HEV genome contains a hypervariable region (HVR) in ORF1. To demonstrate the utility of the avian HEV infectious clone, several mutants with various deletions in and beyond the known HVR were derived from the pT11-aHEV-K clone. The HVR-deletion mutants were replication competent in LMH cells, although the deletion mutants extending beyond the known HVR were non-viable. By using the pT11-aHEV-K infectious clone as the backbone, an avian HEV luciferase reporter replicon and HVR-deletion mutant replicons were also generated. The luciferase assay results of the reporter replicon and its mutants support the data obtained from the infectious clone and its derived mutants. To further determine the effect of HVR deletion on virus replication, the capped RNA transcripts from the wild-type pT11-aHEV-K clone and its mutants were injected intrahepatically into chickens. The HVR-deletion mutants that were translation competent in LMH cells displayed in chickens an attenuation phenotype of avian HEV infectivity, suggesting that the avian HEV HVR is important in modulating the virus infectivity and pathogenicity.
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Soo-Jeong
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Byung-Woo
authors.initials: BW
authors.lastname: Lee
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Hyun-Woo
authors.initials: HW
authors.lastname: Moon
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Haan Woo
authors.initials: HW
authors.lastname: Sung
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Byung-Il
authors.initials: BI
authors.lastname: Yoon
authors.affiliation: Department of Biomedical Sciences and Pathobiology, College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061-0913, USA.
authors.forename: Xiang-Jin
authors.initials: XJ
authors.lastname: Meng
authors.affiliation: Department of Veterinary Microbiology, College of Veterinary Medicine and Institute of Veterinary Science, Kangwon National University, Chuncheon, Gangwon 200-701, Republic of Korea.
authors.forename: Hyuk Moo
authors.initials: HM
authors.lastname: Kwon
mesh_terms: D032761:Animal Experimentation; D000818:Animals; D002645:Chickens; D018076:DNA, Complementary / Q000235:genetics*; D004279:DNA, Viral / Q000235:genetics*; D005838:Genotype; D006524:Hepatitis, Viral, Animal / Q000473:pathology / Q000821:virology*; D022781:Hepatocytes / Q000821:virology; D052678:Hepevirus / Q000145:classification / Q000235:genetics* / Q000502:physiology*; D008297:Male; D011201:Poultry Diseases / Q000473:pathology / Q000821:virology; D012327:RNA Virus Infections / Q000473:pathology / Q000662:veterinary* / Q000821:virology; D014779:Virus Replication
chemical_list: D018076:DNA, Complementary; D004279:DNA, Viral