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A Cell Culture Model for Producing High Titer Hepatitis E Virus Stocks
Published on: June 26, 2020
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The hepatitis E virus ORF1 hypervariable region confers partial cyclophilin dependency
Frazer J T Buchanan1, Shucheng Chen2, Mark Harris1
1School of Molecular and Cellular Biology, Faculty of Biological Sciences and Astbury Centre for Structural Molecular Biology, University of Leeds, Leeds, LS2 9JT, UK.
The Journal of General Virology
|November 9, 2023
Summary
Hepatitis E virus (HEV) replication does not strictly require cyclophilins A and B (CypA/B). However, silencing CypB can impact HEV replication, suggesting a potential genotype-specific role for cyclophilins in HEV infection.
Area of Science:
- Virology
- Hepatology
- Molecular Biology
Background:
- Hepatitis E virus (HEV) causes over 20 million acute hepatitis cases annually, with high mortality in pregnant women.
- Cyclophilins (CypA/B) are crucial for replication of many RNA viruses, including Hepatitis C Virus (HCV), and are abundant in liver cells.
- Understanding HEV lifecycle is limited by experimental system constraints.
Purpose of the Study:
- To investigate the necessity of cyclophilins A and B (CypA/B) for Hepatitis E virus (HEV) genome replication.
- To explore the potential of cyclophilins as pan-viral therapeutic targets against HEV.
Main Methods:
- Utilized sub-genomic HEV replicons for experimental analysis.
- Employed pharmacological inhibition using cyclosporine A (CsA).
- Used small hairpin RNA (shRNA) for gene silencing of CypA and CypB.
Main Results:
- CypA and CypB were found not to be essential for HEV replication.
- Silencing of CypB demonstrated a reduction in HEV replication for certain isolates and cell types.
- HEV sequence variability, particularly in the hypervariable region, influenced sensitivity to cyclophilin silencing.
Conclusions:
- HEV exhibits atypical replication requirements regarding cyclophilins compared to other RNA viruses.
- The role of cyclophilins in HEV replication may be specific to viral genotype and sequence.
- Further research is needed to elucidate the precise, potentially nuanced, role of cyclophilins in HEV infection.
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