A rapid method to identify cytotoxic T-lymphocyte peptide epitopes from HLA-A2 (+) donors.

It would be useful to develop a method to rapidly identify peptide epitopes for vaccine development. We present an algorithm that can predict sequences that have a high binding activity for HLA-A2. These sequences were able to induce specific cytolytic cells from human peripheral blood lymphocytes (PBMC). A computer-assisted algorithm was constructed to predict binding activity for HLA-A2, according to anchoring amino acid combinations. The human papillomavirus (HPV) type 18 E7 oncoprotein was used to test the algorithm. Peptides predicted to bind were synthesized and binding activity was determined by using the T2 cell assay. T2 cells pulsed with HPV-18 peptides were incubated with PBMC. Cytotoxicity assays were performed. From 110 possible sequences, four peptides were found to have a high binding activity. One of these peptides was able to induce significant lysis. Using this selection process only 3.6% of the total number of possible sequences was synthesized to identify an immunogenic peptide. Our algorithm with the T2 binding assay allows a rapid method to detect peptide epitopes.