Abstract: An isolated protein comprising a hepatitis B surface antigen (HBsAg) amino acid sequence, and encoding nucleic acid, are provided wherein one or more immunogenic T cell epitopes of the HBsAg are respectively substituted with one of more immunogenic T cell epitopes of a protein other than HBsAg. Typically, the T cell epitopes are of a pathogen or tumour protein. The isolated protein may have endogenous HBsAg epitopes substituted with multiple copies of the same epitope or with different HBsAg epitopes. B cell epitopes may also be present.

Abstract: The invention relates to a subunit papillomavirus vaccine which is protective against anogenital human Papillomavirus (HPV) infection. Peptides are also provided, which constitute an antigenic component of the vaccine. The peptide includes the sequence DRAHYNI (SEQ ID NO:11) and structural homologues thereof which concern a single amino acid substitution. The peptide is linked directly or indirectly to one or more amino acid sequences which correspond to a B epitope HPV16 and HPV18. The DRAHYNI (SEQ ID NO:11) sequence corresponds to a T helper epitope sequence.