Session Title: GENERAL SESSION 3 & AWARDS 2
Presentation Date: 02 APR, 2011
BLOCK OF HEPATITIS DELTA INFECTION BY THE ENTRY INHIBITOR MYRCLUDEX B IN UPA MICE: ESTABLISHMENT OF AN EFFICIENT MOUSE MODEL FOR HUMAN HBV/HDV INFECTION
M. Lutgehetmann1,2*, L.V. Mancke1, L. Allweiss1, T. Volz1, M. Helbig1, A.W. Lohse1, A. Alexandrov3, J. Petersen4, S. Urban5, M. Dandri1
1Department of Internal Medicine, 2Department of Medical Microbiology, Virology and Hygiene, University Medical Center Hamburg-Eppendorf, Hamburg, 3Vision 7 GMBH, Frankfurt, 4IFI Institute for Interdisciplinary Medicine at Asklepios Clinic St. Georg, Hamburg, 5Department of Infectious Diseases, Molecular Virology, University Hospital Heidelberg, Heidelberg, Germany. *firstname.lastname@example.org
Hepatitis delta virus (HDV) is a subviral agent which can cause severe liver disease in association with hepatitis B virus (HBV). To date no HDV-specific antiviral drugs are available and interferon alpha remains the only treatment option. Establishment of more suitable HDV infection models may improve our understanding of the HDV replication mechanisms and permit in vivo preclinical antiviral drug evaluations.
Aim of the study was to use uPA/SCID mice repopulated with primary human hepatocytes to establish de novo HDV infection and to test the ability of an HBV envelope-derived entry inhibitor (Myrcludex-B) to prevent HDV infection in vivo.
Methods: Naïve and chronically HBV infected humanized mice were inoculated with a patient-derived serum containing 10E6 HDV-RNA (genotype1) and 10E8 HBV-DNA genome equivalents. Serological and intrahepatic HBV (rcDNA, cccDNA) and HDV-RNA levels were determined by quantitative RT-PCR over time. Presence of HBsAg, HBcAg and delta-Ag was ascertained by immunohistochemistry. Myrcludex-B, a novel entry inhibitor for HBV in preclinical tests was injected (2mg/kg daily) 1h before infection and in the following 4 days in 3/6 mice.
Results: Establishment of HDV infection was highly efficient both in HBV-infected and naïve chimeric mice (7/7 and 13/13, respectively). In HDV super-infected mice, delta-Ag positive human hepatocytes were detected already at 2 weeks post-infection (p.i), whereas the increase of HDV-positive cells demonstrated spreading of infection among human hepatocytes. In the setting of HBV/HDV simultaneous infection, HDV viremia reached peak levels between 6-8 weeks p.i. (up to 5*10^8 copies HDV/ml), while the peak of HBV viremia was detected 10 weeks p.i. Since a great majority of human hepatocytes stained delta-Ag-positive long before HBV spreading was completed, these in vivo studies confirmed that HDV can replicate intrahepatically in the absence of HBV. The antiviral study showed that all mice receiving Myrcludex-B remained negative for HDV and HBV serological and intrahepatic markers, whereas untreated mice became infected.
i) We established an efficient model of chronic HBV/HDV infection for the study of HDV and for preclinical antiviral drug evaluations.
ii) We could demonstrate that HBV entry inhibitors can completely block de-novo HDV infection of human hepatocytes in vivo.