P-321

Cyclooxygenase‐2 is a promising target for cancer immunotherapy. Here, we designed the analogues p321‐9L and p321‐1Y9L (YLIGETIKL) from cyclooxygenase‐2‐derived native peptide p321. Then, we tested the binding affinity and stability of the analogues and their ability to elicit specific immune response both in vitro (from PBMCs of HLA‐A*02+ healthy donors) and in vivo (from HLA‐A2.1/Kb transgenic mice). Our results indicated that the activity of cytotoxic T lymphocytes induced by p321‐9L and p321‐1Y9L was more potent than that of p321. In conclusion, the epitope analogue, especially p321‐1Y9L, may be a good candidate which could be used to the immunotherapy of patients with tumours expressing cyclooxygenase‐2.