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A Competent Hepatocyte Model Examining Hepatitis B Virus Entry through Sodium Taurocholate Cotransporting Polypeptide as a Therapeutic Target
Published on: May 10, 2022
Hepatitis B caused by a hepatitis B surface antigen escape mutant
Eiji Kajiwara1, Yasuhito Tanaka, Tomoko Ohashi
1Department of Gastroenterology, Internal Medicine and Pathology, Nippon Steel Yawata Memorial Hospital, 1-1-1 Harunomachi, Kitakyushu, 805-8508, Japan.
Journal of Gastroenterology
|April 1, 2008
Summary
Hepatitis B virus (HBV) immune escape mutants can cause hepatitis even in vaccinated individuals. A specific mutation (G145R) in the hepatitis B surface antigen (HBsAg) S gene led to vaccine failure and hepatitis.
Area of Science:
- Virology
- Immunology
- Hepatology
Background:
- Amino acid substitutions in the hepatitis B virus (HBV) S gene's major antigenic 'a' determinant can lead to immunization failure.
- Immune escape mutants of hepatitis B surface antigen (HBsAg) pose a challenge to existing immunity.
Observation:
- Clinical hepatitis developed in a healthy individual despite the presence of antibodies to HBsAg.
- Sequencing identified a single amino acid substitution, G145R, within the HBsAg 'a' determinant of the isolated HBV strain.
Findings:
- The identified G145R mutation within the HBsAg 'a' determinant represents an immune escape mutant.
- This mutant HBV strain caused hepatitis in an individual with pre-existing immunity.
Implications:
- Immune escape mutants can cause hepatitis B even in the presence of vaccine-induced or natural immunity.
- Antiviral treatment, such as lamivudine, can effectively clear HBV DNA and antigens.
- Understanding these mutations is crucial for developing more effective HBV vaccines and therapies.
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