title: Identification and quantification of a naturally presented peptide as recognized by cytotoxic T lymphocytes specific for an immunogenic tumor variant.
abstract: The target antigen recognized by H-2Kd-restricted cytotoxic T lymphocytes (CTLs) specific for a mutagen-induced antigen on DBA/2-derived tumor P815 was identified as the product of a normal cellular gene encompassing a point mutation. Using synthetic peptides, the epitope recognized by these CTLs was narrowed down to be contained within the undecamer KYQAVTTTLEE, incorporating the point mutation. The allele-specific peptide motif for H-2Kd molecules allowed us to predict the peptide naturally presented by the tumor cells to be the nonamer KYQAVTTTL. Isolation of the natural tum(-)-specific peptide from P198.3 tumor cells and biochemical comparison with the synthetic nonamer confirmed the prediction. This natural nonapeptide is represented by approximately 100 copies per tumor cell.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D000939:Epitopes / Q000276:immunology*; D006183:H-2 Antigens / Q000276:immunology; D012515:Mast-Cell Sarcoma / Q000276:immunology*; D051379:Mice; D008811:Mice, Inbred DBA; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000276:immunology* / Q000302:isolation & purification; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014407:Tumor Cells, Cultured / Q000276:immunology
chemical_list: D000951:Antigens, Neoplasm; D000939:Epitopes; D006183:H-2 Antigens; C024755:H-2K(K) antigen; D010446:Peptide Fragments