conclusions these data will be beneficial for designing more advanced antibodies for the recognition of the hbsag in diagnostics. in addition, the results of this study may assist in the design or development of more effective hepatitis b vaccines. results the g145r mutation causes a considerable reduction in the immunogenic activity of the hbsag through a conformational change in the hbsag ant...

BACKGROUND Vaccine-escaped hepatitis B virus (HBV) mutations occur within the "a" determinant area, which is located in the major hydrophilic region (MHR) of the hepatitis B surface antigen (HBsAg) protein. It is now well established that the common G145R mutation is highly capable of escaping from HBsAg immune recognition. However, the impacts of this mutation on the structure and immunogenic ...

BACKGROUND A missense mutation in exon 7 (R249S) of the p53 tumor suppressor gene is characteristic of aflatoxin B1 (AFB1) exposure. AFB1 is believed to have a synergistic effect on hepatitis virus B (HBV) carcinogenesis. However, results of studies comparing R249S prevalence among patients are conflicting. The aim of this study was to determine the prevalence of the R249S mutation in hepatocel...

Hepatitis B virus (HBV) infection can cause HBV-related cirrhosis, liver failure, and hepatocellular carcinoma. At present, a hepatitis B surface antigen (HBsAg) blood test is the primary clinical and diagnostic marker for the identification of a chronic HBV infection. In the current study, we isolated a novel HBV mutant from a chronic HBV patient, capable of causing a false negative test resul...

mutations in the human hepatitis b virus (hbv) genome contribute to its escape from host immune surveillance and result in persistent infections. the aim of this study was to characterize the molecular variations of the surface gene and protein in chronically-infected patients from the southern part of iran. the  surface  genes  from  12  hbv  chronic  carriers  were  amplified, sequenced  and ...

The hepatitis B virus(HBV) polymerase rtA181T mutation is selected during long-term antiviral therapy. As the polymerase gene completely overlaps with the envelope (S) gene, HBV rtA181T mutation also carries sW172 mutations. In this study, we investigated whether there were biological differences between rtA181T/sW172* (coding truncated HBsAg) and rtA181T/sW172L (coding substituted HBsAg) mutan...

Background: The antibody response to hepatitis B surface antigen (HBsAg) controls hepatitis B virus infection. The "a" determinant of HBsAg is the most important target for protective antibody response, diagnosis and immunoprophylaxis. Mutations in this area may induce immune escape mutants and affect the performance of HBsAg assays. Objectives: To construct clinically relevant recombinant muta...

Small hepatitis B virus surface protein (S-HBsAg) variant Y100C has been associated with HBsAg-negative phenotype. To determine whether Y100C substitution yields impaired HBsAg or small amounts of HBsAg that may reduce HBsAg detection by commercial anti-HBsAg antibodies, two eukaryotic expression plasmids, one containing a wild-type S and the other an S gene from a Y100C variant, were construct...

Alteration in hepatitis B virus (HBV) secretion efficiency may have pathological consequences. Naturally occurring mutations that regulate virion secretion have not been defined. We recently identified HBV genomes displaying high (4B), substantially reduced (3.4), or negative (4C) virion secretion. In the present study, the underlying mutations were mapped. A T552C point mutation in the 4B geno...

Background: Genetic changeability of hepatitis B virus (HBV) signifies a challenge for the sensitivity of immunologic and molecular diagnostics. Therefore, knowing the spread of HBV genotypes (GENs) and mutation has considerable impacts on treatment strategies, vaccination program, diagnosis, and prevention. The present study aimed to detect HBV GENs and mutants in HBsAg-positive patients. Meth...