Inhibition of HBV gene expression and replication by stably expressed interferon-alpha1 via adeno-associated viral vectors

J Gene Med. 2008 Jun;10(6):619-27. doi: 10.1002/jgm.1174.

Abstract

Background: Interferon-alpha2 (IFNalpha2) is routinely used for anti-hepatitis B virus (HBV) treatment. However, the therapeutic efficiency is unsatisfactory, particularly in East Asia. Such inefficiency might be a result of the short half-life, relatively low local concentration and strong side-effects of interferons. Frequent and repeated injection is also a big burden for patients. In the present study, a single dose of vector-delivered IFNalpha1 was tested for its anti-HBV effects.

Methods: Adeno-associated viral vector (AAV-IFNalpha1) was generated to deliver the IFNalpha1 gene into hepatocytes. IFNalpha1, hepatitis B surface (HBsAg) and e (HBeAg) antigens were measured by enzyme-linked immunosorbent assay and/or western blotting. The level of viral DNA was measured by quantitative real-time polymerase chain reaction.

Results: AAV-IFNalpha1 effectively transduced HBV-producing cells (HepAD38) and mouse hepatocytes, where IFNalpha1 was expressed in a stable manner. Both intracellular and extracellular HBsAg and HBeAg were significantly reduced in vitro. In the HBV-producing mice, the concentration of IFNalpha1 in the liver was eight-fold higher than that in plasma. Compared with control groups, HBeAg/HBsAg antigen levels were reduced by more than ten-fold from day 1-5, and dropped to an undetectable level on day 9 in the AAV-IFNalpha1 group. Concurrently, the level of viral DNA decreased over 30-fold for several weeks.

Conclusions: A single dose administration of AAV-IFNalpha1 viral vector displayed prolonged transgene expression and superior antiviral effects both in vitro and in vivo. Therefore, the use of AAV-IFNalpha1 might be a potential alternative strategy for anti-HBV therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blotting, Western
  • Cells, Cultured
  • Dependovirus
  • Enzyme-Linked Immunosorbent Assay
  • Gene Expression Regulation, Viral / immunology*
  • Genetic Vectors / genetics
  • Hepatitis B / therapy*
  • Hepatitis B Antigens / metabolism
  • Hepatitis B virus / immunology*
  • Hepatitis B virus / metabolism
  • Immunotherapy / methods*
  • Interferon-alpha / metabolism*
  • Mice
  • Virus Replication / immunology*

Substances

  • Hepatitis B Antigens
  • Interferon-alpha