Mutational events during the primary propagation and consecutive passages of hepatitis E virus strain JE03-1760F in cell culture.
We recently developed a cell culture system for hepatitis E virus (HEV) in PLC/PRF/5 cells, using a genotype 3 HEV (JE03-1760F strain). Thirteen generations of consecutive passages of culture supernatant were successfully carried out in PLC/PRF/5 cells, with the highest HEV load reaching 10(8) copies/ml in the culture medium. Based on continuous release of progenies into culture medium, 50% tissue culture infectivity doses were estimated to be 2.0 x 10(3) copies for wild-type JE03-1760F and 1.4 x 10(2) copies for p13 (progeny in the thirteenth passage). Earlier appearance and greater increase in the yield of progenies in the culture supernatant were evident in p13 compared with wild-type. The cell culture-produced variants in primary propagation (p0) and consecutive passages (p5 [fifth passage], p10 [tenth], and p13) differed from the wild-type virus by 1, 9, 18, and 19 nucleotides (nt), respectively, over the entire genome of 7226nt, excluding the poly(A) tail. Three of five non-synonymous mutations in p13 were shared by a variant (fifth passage) in another series of passages of JE03-1760F. These results suggest that adaptation of HEV variants to growth in vitro is associated with a limited number of mutations similar to hepatitis A virus.
Lorenzo
Felipe R
FR
Department of Infection and Immunity, Division of Virology, Jichi Medical University School of Medicine, Shimotsuke-Shi, Tochigi-Ken, Japan.
Tanaka
Toshinori
T
Takahashi
Hideyuki
H
Ichiyama
Koji
K
Hoshino
Yu
Y
Yamada
Kentaro
K
Inoue
Jun
J
Takahashi
Masaharu
M
Okamoto
Hiroaki
H
D000368:Aged; D019943:Amino Acid Substitution; D045744:Cell Line, Tumor; D005243:Feces / Q000821:virology; D016751:Hepatitis E / Q000821:virology*; D016752:Hepatitis E virus / Q000145:classification / Q000235:genetics* / Q000254:growth & development* / Q000472:pathogenicity; D006801:Humans; D008969:Molecular Sequence Data; D009154:Mutation; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics* / Q000378:metabolism; D017423:Sequence Analysis, RNA; D012692:Serial Passage; D014776:Virus Cultivation
D012367:RNA, Viral