Development of a primary tamarin hepatocyte culture system for GB virus-B: a surrogate model for hepatitis C virus.
GB virus-B (GBV-B) causes an acute hepatitis in tamarins characterized by increased alanine transaminase levels that quickly return to normal as the virus is cleared. Phylogenetically, GBV-B is the closest relative to hepatitis C virus (HCV), and thus GBV-B infection of tamarins represents a powerful surrogate model system for the study of HCV. In this study, the course of infection of GBV-B in tamarins was followed using a real-time 5' exonuclease (TaqMan) reverse transcription-PCR assay to determine the level of GBV-B in the serum. Peak viremia levels exceeded 10(9) genome equivalents/ml, followed by viral clearance within 14 to 16 weeks. Rechallenge of animals that had cleared infection resulted in viremia that was limited to 1 week, suggestive of a strong protective immune response. A robust tissue culture system for GBV-B was developed using primary cultures of tamarin hepatocytes. Hepatocytes obtained from a GBV-B-infected animal maintained high levels of cell-associated viral RNA and virion secretion for 42 days of culture. In vitro infection of normal hepatocytes resulted in rapid amplification of cell-associated viral RNA and secretion of up to 10(7) genome equivalents/ml of culture supernatant. In addition, infection could be monitored by immunofluorescence staining for GBV-B nonstructural NS3 protein. This model system overcomes many of the current obstacles to HCV research, including low levels of viral replication, lack of a small primate animal model, and lack of a reproducible tissue culture system.
Beames
B
B
Department of Virology and Immunology, Southwest Regional Primate Research Center, Southwest Foundation for Biomedical Research, San Antonio, Texas 78227, USA.
Chavez
D
D
Guerra
B
B
Notvall
L
L
Brasky
K M
KM
Lanford
R E
RE
D000818:Animals; D018929:Cell Culture Techniques; D004195:Disease Models, Animal; D018067:Flaviviridae; D016174:Hepacivirus; D006524:Hepatitis, Viral, Animal; D008099:Liver / Q000473:pathology / Q000821:virology*; D012452:Saguinus