[Generation of HER2 specific, HLA-A24 restricted CTLs derived from a healthy donor]

Cancer vaccine therapy is one of the latest treatment modalities for advanced cancer. In this study, we have newly identified two HER2 peptide epitopes restricted by HLA-A24, which are the most common alleles in Japanese. We have generated mature DCs from PBMCs in the HLA-A24+ healthy donor. Mature DCs were co-incubated with HER2 peptide, and then autologous PBMCs were co-incubated with antigen-loaded DCs. In this way, we have generated HER2 reactive and HLA-A24-restricted CTL lines. The CTL's specificity was evaluated with ELISPOT analysis and cytotoxic assay. In the two CTL lines, the specificity of TISI loaded with HER2/neu peptide used for each CTL induction was recognized, and that specific cytotoxicity was also found against cancer cell lines expressing HLA-A24 and HER2. In conclusion, we have newly identified two HER2 peptide epitopes restricted by HLA-A24 and confirmed that these epitopes will be new targets for cancer vaccine therapy.