Detection of peptide‐specific cytotoxic T‐lymphocyte precursors used for specific immunotherapy of pancreatic cancer

The prognosis of pancreatic cancer is extremely poor with a 5‐year survival of approximately 3%. Thus, the development of new treatment modalities, including a specific immunotherapy, is required. Our study investigated whether cytotoxic T‐lymphocyte (CTL) precursors reacting to peptides with vaccine candidates (13 peptides for HLA‐A2 + or ‐A24 + patients, respectively) were detectable in the prevaccination peripheral blood mononuclear cells (PBMCs) of 15 pancreatic cancer patients. Peptide‐specific CTL precursors were detectable in the majority (11 of 15, 73%) of patients, with a mean positive number of 1.5 peptides (ranging from 0–5 peptides) per patient. Positive peptide profiles varied among patients. These results may provide a scientific basis for a new kind of cancer immunotherapy, namely, a CTL precursor‐oriented peptide vaccine, for pancreatic cancer patients. © 2001 Wiley‐Liss, Inc.