肝臓学および胃腸疾患ジャーナル
オープンアクセス

概要

Sequence Variability of Hepatitis B Virus (HBV) Surface Antigen Gene (S Gene) among the Non-Responders of Antiviral Therapy

Naveed Alam, Zubaida Daudzai, Werasak Surareungchai

Prolonged administration of antiviral therapy for chronic hepatitis B may result in the development of hepatitis B viral mutants. To gain insight into the mechanism involved in the sequence variability of Hepatitis B Virus (HBV) surface antigen gene (S gene) among responders and non-responders to antiviral therapy, baseline characteristics of the patients and sequences within the S region were investigated in pre-treatment serum samples of responders and post-treatment serum samples of non-responders. The data was collected from 15 individuals with chronic hepatitis B from Khyber Pakhtunkhwa (KPK) province, Pakistan. The antiviral response was independent of viral genotypes, and nonresponse to antiviral therapy was associated with a complex variability of the viral mutants. The sequence analysis of the S gene among responders and non-responders patients of pre and post-treatment with antiviral therapy showed variability in DNA sequence marked as Pakistani isolates make a distinct cluster in the phylogenetic tree. The S gene of HBV isolates from KPK province shows some similarities with isolates of other countries. No significant variations of nucleotides in the S gene of HBV was found among the responders and non-responders receiving antiviral therapy indicating that S gene may not be important with respect to treatment outcome. It illustrates that antigenicity of other various HBV proteins can be targeted in order to design more effective vaccines against the local strains.