This invention relates to hepatitis B virus ("HBV") core antigen particles
that are characterized by multiple immunogen specificities. More
particularly, the invention relates to HBV core antigen particles
comprising immunogens, epitopes, or other related structures, crosslinked
thereto by ligands which are HBV capsid-binding peptides that selectively
bind to HBV core protein. Such particles may be used as delivery systems
for a diverse range of immunogenic epitopes, including the HBV
capsid-binding peptides, which advantageously also inhibit and interfere
with HBV viral assembly by blocking the interaction between HBV core
protein and HBV surface proteins. Mixtures of different immunogens and/or
capsid-binding peptide ligands may be crosslinked to the same HBV core
particle. Such resulting multicomponent or multivalent HBV core particles
may be advantageously used in therapeutic and prophylactic vaccines and
compositions, as well as in diagnostic compositions and methods using
them.