Table of Contents
Hepatitis Research and Treatment
Volume 2011, Article ID 695859, 4 pages
Research Article

Expression of Hepatitis B Virus Surface Antigen Containing Y100C Variant Frequently Detected in Occult HBV Infection

1Laboratory of Molecular Virology, Oswaldo Cruz Institute, FIOCRUZ, Avenida Brasil 4365, 21045-900 Rio de Janeiro, RJ, Brazil
2INSERM U871, 151 Cours Albert Thomas, 69424 Lyon, France

Received 22 November 2010; Accepted 4 January 2011

Academic Editor: William Irving

Copyright © 2011 Francisco C. A. Mello et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


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 constructed and their levels of HBsAg compared by ELISA after transfection of HuH7 cells. Unexpectedly, the extracellular HBsAg levels detected with Y100C plasmid were higher than those observed with the wild-type plasmid, but without statistical significance. We concluded that the Y100C substitution alone did not play a role in reducing HBsAg amounts or HBsAg affinity by commercial ELISA assay. Further studies on in vitro replication fitness with the complete genome of HBV isolates displaying or not Y100C substitution may elucidate whether this mutation affects HBV replication and consequently HBsAg production.