Mutations in hepatitis B virus surface antigen (HBsAg) involving amino acid substitution within the immunodominant "a" determinant may affect the performance of commercial HBsAg assays. The performances of four HBsAg assays that recently received Conformité Européene marking, Advia Centaur HBsAg (Bayer), Monolisa HBsAg Ultra (Bio-Rad), Liaison HBsAg (Dia Sorin), and Vidas HBsAg Ultra (bioMérieu...

objectives the aim of the present study was to determine the prevalence of anti-hbc and hbsag in blood donors. further, the study aimed to estimate the anti-hbc level at which hbv dna is detected in putative obi cases, as well as to search for mutations in the “a” determinant associated with the non-detection of hbsag in serum. conclusions we observed that as the anti-hbc levels increase, there...

Hepatitis B virus (HBV) infections are sometimes overlooked when using commercial kits to measure hepatitis B virus surface antigen (HBsAg) due to their low sensitivities and reactivities to mutant strains of various genotypes. We developed an ultrasensitive bioluminescent enzyme immunoassay (BLEIA) for HBsAg using firefly luciferase, which is adaptable to a variety of HBsAg mutants, by combini...

METHODS 6,217 sera samples collected from volunteers in six epidemiologically different regions of Russia were tested for serological and molecular markers of HBV infection. A mathematical model developed by the U.S. Centers for Disease Control and Prevention was used to estimate the effect of vaccination and birth dose coverage on the incidence of HB and adverse outcomes of infection. RESULT...

BACKGROUND Hepatitis B virus (HBV) infection is a major global health burden with distinct geographic public health significance. Oman is a country with intermediate HBV carrier prevalence; however, little is known about the incidence of HBV variants in circulation. We investigated the HBV genotype distribution, the occurrence of antiviral resistance, and HBV surface antigen (HBsAg) escape muta...

We read with great interest the article by Ding et al.,1 “Mutations in the S gene and in the overlapping reverse transcriptase region in chronic hepatitis B Chinese patients with coexistence of HBsAg and anti-HBs”. We would like to specify some additional issues related to the coexistence of HBsAg and antiHBs in a summary. The rate of simultaneous HBsAg and anti-HBs serological profile ranged f...

We modified and automated a highly sensitive chemiluminescent enzyme immunoassay (CLEIA) for surface antigen (HBsAg) detection using a combination of monoclonal antibodies, each for a specific epitope of HBsAg, and by improving an earlier conjugation technique. Of 471 hepatitis B virus (HBV) carriers seen in our hospital between 2009 and 2012, 26 were HBsAg seronegative as determined by the Abb...

A renal transplant recipient became persistently positive for hepatitis B virus (HBV) despite preexisting anti-hepatitis B surface (HBs) antibodies. The antigenicity and immunogenicity of wild-type (wt) and mutant HBs antigens (Ags) were compared. In contrast to wt HBsAg, genetic vaccination with mutant HBsAgs did not induce anti-HBs. Thus, mutations within HBsAg may enable HBV to escape immuno...

This study aimed to determine the prevalence and mutational patterns of lamivudine-resistant hepatitis B virus (HBV) strains in chronically infected Serbian patients. The study included 154 patients on long-term lamivudine monotherapy. Resistance-associated mutations were identified by direct sequencing of the S/P gene. The genotypic resistance to lamivudine was confirmed in 54.5% of patients. ...

HBV is a member of Hepadnavirus genus. HBV is a DNA virus with a diameter of 42 nm consisting of an outer lipid envelope which contains proteins HBsAg, pre-S1 and pre-S2. HBsAg is a product of ‘s’ gen. The s geneinvolves ‘a’ epitope124. -147. codones and this region is the affecting region for anti-HBs antibody binding. Vaccine /Immunglobulin escape mutations occur at HBV DNA s gene’s ‘a determ...