Prediction and binding of a mutant p53 peptide to MHC class I molecule]

To predict tumor antigenic peptides from the intact amino acid sequence of tumor antigens, thereby providing a guide to the design and development of tumor peptide-based vaccines.Antigenic peptides were predicted by using a computer program PEPMOTIF based on MHC class I allele-specific consensus motifs; and a scoring system was established to assess the likelihood of the peptides to bind to MHC class I molecules. MHC class I-peptide binding assay and MHC class I-peptide stabilization assay were used to determine the binding ability and affinity of the predicted peptides.Three peptides derived from mouse mutant p53 were predicted. mp53P132F(LNKLFFQL) was shown to bind to H-2Kb, but not H-2Db. mp53P246S (MGGMNRSPIL) and mp53P270C (GRDSFEVCV) bound to neither H-2Kb nor H-2Db. A relationship was found between peptide scores and binding of the peptides to the relevant MHC class I molecules.The computer program PEPMOTIF combining with a scoring system is a simple and efficient tool for predicting MHC class I binding peptides derived from antigenic proteins.