title: Assembly of hepatitis delta virus-like empty particles in yeast.
abstract: Large delta antigen (L-HDAg) of hepatitis delta virus (HDV) and small-form hepatitis B surface antigen (HBsAg) of helper hepatitis B virus have previously been shown to be the minimum components for the assembly of HDV-like particles in mammalian cells. Extending from this finding, we coexpressed L-HDAg and small HBsAg in Saccharomyces cerevisiae to study their assembly in yeast cells. The assembly of virus particles from L-HDAg and HBsAg in yeast was demonstrated by their coexistence in the same isopycnic fractions and by the coimmunoprecipitation of L-HDAg with HBsAg using an antibody against HBsAg (anti-HBs). Furthermore, after purification by affinity chromatography with anti-HBs, HDV-like particles with size and morphology similar to those derived from mammalian cells could be visualized by electron microscopy. Mice immunized with yeast-derived HDV-like particles simultaneously acquired antibodies against HBsAg and HDAg, indicating that both viral proteins are antigenic. The results indicated that S. cerevisiae could serve as a host for the assembly of HDV-like empty particles. This system may be useful in investigating cellular processes involved in HDV assembly and in producing ample amount of HDV-like particles for structural and immunological studies.
authors.affiliation: Hepatitis Research Center, National Taiwan University Hospital, Taipei.
authors.forename: H L
authors.initials: HL
authors.lastname: Wu
authors.forename: P J
authors.initials: PJ
authors.lastname: Chen
authors.forename: J J
authors.initials: JJ
authors.lastname: Mu
authors.forename: W K
authors.initials: WK
authors.lastname: Chi
authors.forename: T L
authors.initials: TL
authors.lastname: Kao
authors.forename: L H
authors.initials: LH
authors.lastname: Hwang
authors.forename: D S
authors.initials: DS
authors.lastname: Chen
mesh_terms: D000818:Animals; D003673:Defective Viruses / Q000235:genetics / Q000254:growth & development / Q000276:immunology; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D015870:Gene Expression; D006508:Hepatitis Antibodies / Q000096:biosynthesis; D018963:Hepatitis Antigens / Q000235:genetics; D006510:Hepatitis B Antibodies / Q000096:biosynthesis; D006514:Hepatitis B Surface Antigens / Q000235:genetics; D006515:Hepatitis B virus / Q000235:genetics / Q000276:immunology; D003698:Hepatitis Delta Virus / Q000235:genetics / Q000254:growth & development* / Q000276:immunology; D035923:Hepatitis delta Antigens; D007114:Immunization; D007181:Inclusion Bodies, Viral / Q000648:ultrastructure; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000648:ultrastructure / Q000821:virology
chemical_list: D006508:Hepatitis Antibodies; D018963:Hepatitis Antigens; D006510:Hepatitis B Antibodies; D006514:Hepatitis B Surface Antigens; D035923:Hepatitis delta Antigens; C442244:hepatitis delta virus large antigen