|
- 现金
- 62111 元
- 精华
- 26
- 帖子
- 30437
- 注册时间
- 2009-10-5
- 最后登录
- 2022-12-28
|
PS-155
HBV entry inhibition after interferon alpha treatment hinders
HBV rebound in hepatocytes that became negative for all HBV
markers during interferon treatment
Lena Allweiss1, Katja Giersch1, Tassilo Volz1, Ansgar W. Lohse1,2,
Jörg Petersen3, Stephan Urban2,4, Marc Luetgehmann2,5,
Maura Dandri1,2. 1University Medical Center Hamburg-Eppendorf,
I. Department of Internal Medicine, Hamburg, Germany; 2German
Center for Infection Research (DZIF), Hamburg-Lübeck-Borstel and
Heidelberg sites, Germany; 3Asklepios Clinic St. Georg, IFI Institute for
Interdisciplinary Medicine, Hamburg, Germany; 4University Hospital
Heidelberg, Department of Infectious Diseases, Molecular Virology,
Heidelberg, Germany; 5University Medical Center Hamburg-Eppendorf,
Institute of Microbiology, Virology and Hygiene, Hamburg, Germany
Email: [email protected]
Background and aims: Treatment with interferon alpha (IFNα)
can exert both immunomodulatory and antiviral effects, such as
suppression of HBV transcription and cccDNA degradation. In this
study, we aimed to investigate to which extent these antiviral effects
take place in HBV-infected human hepatocytes in vivo and whether
these effects can persist after treatment cessation. Moreover, we
employed HBV entry inhibition to assess the role of new infection
events in HBV rebound.
Methods: We treated HBV infected human liver chimeric mice with
pegylated IFNα for 6 weeks (n = 13+5 untreated controls). Then, mice
were either sacrificed (n = 5) or treatment was stopped to assess
serological and intrahepatic viral changes for additional 6 weeks,
either in the presence (n = 4) or absence of the entry inhibitor
Myrcludex B (MyrB) (n = 4). MyrB treatment started 3 days before the
last IFNα injection. HBV loads were analysed in serum and liver by
qPCR. RNA in situ hybridization (RNA-ISH) and immunofluorescence
were used to visualize both HBV transcription and the presence
of SMC6, a component of the “structural maintenance of chromosomes
complex” SMC5/6 which is degraded by the HBx protein, and
hence may serve as a cellular marker of cccDNA suppression or
clearance.
Results: Six weeks of IFNα treatment reduced median levels of
viremia (1.2log), HBV transcripts (3.6fold) and cccDNA (4.3fold). As
expected, SMC6 protein was degraded in most hepatocytes in the
livers of HBV-infected control mice, but it was clearly detected in
IFNα-treated mice. After stopping IFNα, HBV rebound occurred in 3 to
6 weeks and was accompanied by renewed SMC6 degradation in
most human hepatocytes. Of note, we observed viremia increase also
in MyrB-treated mice; however, entry inhibition blocked intrahepatic
HBV rebound in a large proportion of human hepatocytes (>40%),
which remained SMC6 positive and negative for HBcAg and HBV RNA
(RNA-ISH). Interestingly, intrahepatic cccDNA levels in mice receiving
MyrB during rebound remained as low as in mice sacrificed at the end
of IFNα treatment.
Conclusion: Reappearance of the SMC5/6 complex in HBV-infected
human hepatocytes in mice treated with IFNα did not hinder HBV
reactivation after drug withdrawal in the setting of an established
HBV infection. However, MyrB clearly maintained HBV negativity in a
substantial proportion of human hepatocytes, suggesting that these
cells had cleared cccDNA during IFNα treatment and that new
infection events play a key role in HBV rebound post treatment. |
|
发表于 2019-4-15 12:44