Three years ago we discovered a hepatitis virus in Beechey ground squirrels (GSHV) with ultrastructural, antigenic, molecular and biological properties similar to those of hepatitis B virus (HBV) of man and woodchuck hepatitis virus (WHV). In the past 3 years we have studied the host range of GSHV, its antigenic and polypeptide structure, its DNA structure and the viral DNA forms in infected liver. Little or no hepatitis and no hepatomas have been observed in chronically GSHV infected ground squirrels in contrast to moderately severe hepatitis and hepatomas frequently observed in WHV infected woodchucks and HBV infected humans. We propose to investigate the basis for the difference in incidence and severity of liver disease in the different virus-host systems. We will investigate the infectivity and pathogenicity of GSHV for woodchucks and WHV for ground squirrels to attempt to determine whether a difference in pathogenicity of the two virus, or a difference in response of the two hosts accounts for the observed difference in disease incidence. We will examine the viral DNA forms in GSHV infected ground squirrel liver and determine whether viral DNA becomes integrated in cellular DNA, and compare these findings with results in woodchuck and human systems. We will study the effects of environmental conditions and aflatoxin B1 on the pathogenic effects of GSHV in ground squirrels. We will study replication of GSHV DNA in infected liver and in tissue culture cells if they can be successfully infected. Finally, we will study the effect of antivirals on the high titer persistent infection seen in GSHV.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI020551-03
Application #
3130275
Study Section
Virology Study Section (VR)
Project Start
1984-01-01
Project End
1987-12-31
Budget Start
1986-01-01
Budget End
1986-12-31
Support Year
3
Fiscal Year
1986
Total Cost
Indirect Cost
Name
Stanford University
Department
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
Rivkina, M; Cote, P J; Robinson, W S et al. (1996) Absence of mutations in the p53 tumor suppressor gene in woodchuck hepatocellular carcinomas associated with hepadnavirus infection and intake of aflatoxin B1. Carcinogenesis 17:2689-94
Chen, Y; Marion, P L (1996) Amino acids essential for RNase H activity of hepadnaviruses are also required for efficient elongation of minus-strand viral DNA. J Virol 70:6151-6
Cullen, J M; Marion, P L (1996) Non-neoplastic liver disease associated with chronic ground squirrel hepatitis virus infection. Hepatology 23:1324-9
Chen, Y; Robinson, W S; Marion, P L (1994) Selected mutations of the duck hepatitis B virus P gene RNase H domain affect both RNA packaging and priming of minus-strand DNA synthesis. J Virol 68:5232-8
Rivkina, M B; Cullen, J M; Robinson, W S et al. (1994) State of the p53 gene in hepatocellular carcinomas of ground squirrels and woodchucks with past and ongoing infection with hepadnaviruses. Cancer Res 54:5430-7
Chen, Y; Robinson, W S; Marion, P L (1992) Naturally occurring point mutation in the C terminus of the polymerase gene prevents duck hepatitis B virus RNA packaging. J Virol 66:1282-7
Yuasa, S; Cheung, R C; Pham, Q et al. (1991) Peptide mapping of neutralizing and nonneutralizing epitopes of duck hepatitis B virus pre-S polypeptide. Virology 181:14-21
Sherker, A H; Marion, P L (1991) Hepadnaviruses and hepatocellular carcinoma. Annu Rev Microbiol 45:475-507
Hung, L F; Brumbaugh, A E; Bhatia, G et al. (1991) Effects of purine nucleoside analogues with a cyclobutane ring and erythromycin A oxime derivatives on duck hepatitis B virus replication in vivo and in cell culture and HIV-1 in cell culture. J Med Virol 35:180-6
Cullen, J M; Marion, P L; Sherman, G J et al. (1990) Hepatic neoplasms in aflatoxin B1-treated, congenital duck hepatitis B virus-infected, and virus-free pekin ducks. Cancer Res 50:4072-80

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