RESUMEN
We produced two murine monoclonal antibodies designated S2E1 and S2C11, which recognize S antigen of hepatitis B virus (HBsAg). S2E1 could bind to denatured form of recombinant HBsAg as well as native form of HBsAg, but S2C11 could bind only to native form of HBsAg. Both antibodies reacted with HBsAg in the hepatocyte of patient infected with hepatitis B virus. Analyses of the nucleotide sequences encoding the variable regions of these antibodies revealed that S2E1 and S2C11 utilize variable gene segment which belong to V4/5 gene family and utilize the J5 and Jk4 gene segments, respectively. In addition, the heavy chain of S2E1 express a member of V14 gene family and a member of DSP2.9 and Jh3 gene families. S2C11 is related to the V1 gene family and expresses DFL16.1 gene regions in conjunction with the Jh3 gene segment.