Delineation of contiguous determinants essential for biological functions of the pre-S sequence of the hepatitis B virus envelope protein: its antigenicity, immunogenicity and cell-receptor recognition.

The preS region of the hepatitis B virus (HBV) envelope protein has the following properties: (1) exposure on the surface of the virus; (2) high immunogenicity; (3) involvement in the reaction of the virus with cell receptors and (4) elicitation of antibodies protective against infection. Attempts to mimic B- and T-cell epitopes on the native protein by synthetic peptides were highly successful. This success depended on identification of those regions within the preS sequences which are the most important for biological function of the virus and for immunity, and on the synthesis of long peptides (20-40 residues) containing both B- and T-cell epitopes. Results presented here highlight those subregions of the preS sequence which are the most essential for the antigenicity and immunogenicity of HBV.