Modified DNA fusion vaccine to induce CD8⁺T-cell responses.

The full-length FrC promotional sequence consists of 2 protein domains (Dom), Dom 1 and Dom 2. This is able to amplify antibody and CD4⁺ T-cell responses against fused tumor antigen. To induce CD8⁺ T cells, Dom 2, which contains potentially competitive MHC Class I-binding epitopes, was removed, and the candidate tumor peptide coding sequence was fused to the 3′ end of Dom 1. This engineered construct is able to induce epitope-specific CTL against a range of tumor epitopes.