title: Production of infectious dromedary camel hepatitis E virus by a reverse genetic system: Potential for zoonotic infection.
abstract: The pathogenicity, epidemiology and replication mechanism of dromedary camel hepatitis E virus (DcHEV), a novel hepatitis E virus (HEV), has been unclear. Here we used a reverse genetic system to produce DcHEV and examined the possibility of zoonotic infection.
  
  
  
  Capped genomic RNA derived from a synthetic DcHEV cDNA was transfected into human hepatocarcinoma cells PLC/PRF/5. The DcHEV capsid protein and RNA were detected by an enzyme-linked immunosorbent assay (ELISA) or RT-qPCR. A neutralization test for DcHEV was carried out by using antisera against HEV-like particles. DcHEV was used to inoculate two cynomolgus monkeys to examine the potential for cross-species infection.
  
  
  
  The transfection of PLC/PRF/5 cells with capped DcHEV RNA resulted in the production of infectious DcHEV. The genome sequence analysis demonstrated that both nucleotide and amino acid changes accumulated during the passages in PLC/PRF/5 cells. The cynomolgus monkeys showed serological signs of infection when DcHEV was intravenously inoculated. DcHEV was neutralized by not only anti-DcHEV-LPs antibody, but also anti-genotype 1 (G1), G3 and G4 HEV-LPs antibodies. Moreover, the monkeys immunized with DcHEV escaped the G3 HEV challenge, indicating that the serotype of DcHEV is similar to those of other human HEVs.
  
  
  
  Infectious DcHEV was produced using a reverse genetic system and propagated in PLC/PRF/5 cells. The antigenicity and immunogenicity of DcHEV are similar to those of G1, G3 and G4 HEV. DcHEV was experimentally transmitted to primates, demonstrating the possibility of a zoonotic infection by DcHEV.
  
  
  
  Dromedary camel hepatitis E virus (DcHEV) was produced by a reverse genetic system and grows well in PLC/PRF/5 cells. Cynomolgus monkeys experimentally infected with DcHEV indicated serological signs of infection, suggesting that DcHEV has the potential to cause zoonotic HEV infection.
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan. Electronic address: litc@nih.go.jp.
authors.forename: Tian-Cheng
authors.initials: TC
authors.lastname: Li
authors.affiliation: Department of Microbiology, Nanchang Center for Disease Control and Prevention, Nanchang, Jiangxi, China.
authors.forename: Xianfeng
authors.initials: X
authors.lastname: Zhou
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Yoshizaki
authors.affiliation: Division of Experimental Animals Research, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ami
authors.affiliation: Division of Experimental Animals Research, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Yuriko
authors.initials: Y
authors.lastname: Suzaki
authors.affiliation: Seto Center, Kanonji Institute, The Research Foundation for Microbial Diseases of Osaka University, Seto-cho 4-1-70, Kanonji, Kagawa 768-0065, Japan.
authors.forename: Tomofumi
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Research Institute for Microbial Diseases, Osaka University, Suita, Osaka 565-0781, Japan.
authors.forename: Naokazu
authors.initials: N
authors.lastname: Takeda
authors.affiliation: Department of Virology II, National Institute of Infectious Diseases, Gakuen 4-7-1, Musashi-murayama, Tokyo 208-0011, Japan.
authors.forename: Takaji
authors.initials: T
authors.lastname: Wakita
mesh_terms: D000818:Animals; D002162:Camelus; D004797:Enzyme-Linked Immunosorbent Assay; D016751:Hepatitis E; D016752:Hepatitis E virus; D006801:Humans; D059386:Reverse Genetics; D015047:Zoonoses
keywords: Alanine aminotransferase (ALT); DcHEV; Dromedary camel hepatitis E virus; PLC/PRF/5 cell; Reverse genetics system; Zoonotic infection