title: Clinical isolates of GB virus type C vary in their ability to persist and replicate in peripheral blood mononuclear cell cultures.
abstract: GB virus C/hepatitis G virus (GBV-C) replication in vitro is inefficient and inconsistent. In this study, clinical isolates of GBV-C were evaluated using peripheral blood mononuclear cell (PBMC) based culture methods. Isolates varied consistently in their ability to persistently replicate, and yield increased in cells grown without PHA/IL-2 stimulation. The deduced polyprotein sequence of an isolate that replicated well was determined (GenBank AY196904) and compared to 20 full-length GBV-C sequences. Fourteen of the 16 unique amino acid polymorphisms identified were in the coding regions for nonstructural proteins associated with interferon resistance and RNA replication. These data indicate that clinical GBV-C isolates vary in their ability to persist in culture, do not require PHA/IL-2 stimulation, and that sequence variability in key regulatory regions may affect growth in PBMC cultures. Since GBV-C appears to inhibit HIV replication in a coinfection model, these studies should facilitate determination of the mechanism of this interaction.
authors.affiliation: Departments of Internal Medicine and Research, Iowa City VA Medical Center, University of Iowa, and the Helen C. Levitt Center for Viral Pathogenesis, Iowa City, IA 52242, USA.
authors.forename: Sarah L
authors.initials: SL
authors.lastname: George
authors.forename: Jinhua
authors.initials: J
authors.lastname: Xiang
authors.forename: Jack T
authors.initials: JT
authors.lastname: Stapleton
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002478:Cells, Cultured; D029407:GB virus C / Q000502:physiology*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000821:virology*; D008969:Molecular Sequence Data; D012367:RNA, Viral / Q000097:blood; D014779:Virus Replication
chemical_list: D012367:RNA, Viral