The invention relates to the use of a molecular adjuvant to generate an improved immune response in a host. Over recent years extensive research and development has been undertaken in the development of “vectored vaccines” which can be used as vaccine delivery systems. Vectored vaccines include DNA vectors and recombinant viral and bacterial vectors, which are engineered to express an antigen of interest. The invention provides a nucleic acid construct encoding a protein fusion between an antigen and an invariant chain molecule.
