RÉSUMÉ
<p><b>OBJECTIVE</b>To further study the binding character of hepatitis B surface antigen (HBsAg) and beta 2-glycoprotein I (beta2GP I) and to explore whether beta2GP I plays an important role in the hepatotropism of hepatitis B virus.</p><p><b>METHODS</b>Using Western blot technique, we observed the binding character of the HBsAg with reduced and non-reduced beta2GP I.</p><p><b>RESULTS</b>rHBsAgs with reduced and non-reduced beta2GP I showed identical binding activity.</p><p><b>CONCLUSIONS</b>The binding activity of HBsAg is dependent on tandem residues, but not on conformational structures of beta2GP I. There is a specific binding between HBV and beta2GP I, which may play an important role in HBV infection and is one of the reasons of hepatotropism of HBV.</p>