title: Lysis of ras oncogene-transformed cells by specific cytotoxic T lymphocytes elicited by primary in vitro immunization with mutated ras peptide.
abstract: Ras protooncogenes are activated by characteristic point mutations in a wide variety of malignancies. The expressed p21ras proteins are oncogenic by virtue of single substituted amino acids, usually at position 12 or 61 of the 189-residue p21ras protein. In the current study, the ability of class I major histocompatibility complex (MHC)-restricted T cells to recognize the altered segment of a transforming p21ras protein and to lyse cells transformed by the corresponding ras oncogene was examined. Synthetic ras peptides encompassing the common activating substitution of leucine for glutamine at position 61 were constructed with an amino acid motif appropriate for binding to the H-2Kb murine class I MHC molecule. Cytotoxic T lymphocytes (CTL) specific for bound ras leucine 61 peptide were elicited by in vitro immunization of normal lymphocytes with synthetic peptides. The ras peptide-induced CTL specifically lysed syngeneic fibroblasts transformed by an activated ras gene encoding oncogenic p21ras protein containing the same single amino acid substitution. Thus, in some circumstances, mutated p21ras protein can serve as a tumor-specific antigen.
authors.affiliation: Department of Medicine, Loyola University Chicago, Maywood, Illinois 60153.
authors.forename: D J
authors.initials: DJ
authors.lastname: Peace
authors.forename: J W
authors.initials: JW
authors.lastname: Smith
authors.forename: W
authors.initials: W
authors.lastname: Chen
authors.forename: S G
authors.initials: SG
authors.lastname: You
authors.forename: W L
authors.initials: WL
authors.lastname: Cosand
authors.forename: J
authors.initials: J
authors.lastname: Blake
authors.forename: M A
authors.initials: MA
authors.lastname: Cheever
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002460:Cell Line; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D002999:Clone Cells; D004247:DNA; D005260:Female; D011905:Genes, ras; D015395:Histocompatibility Antigens Class I / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D016296:Mutagenesis; D015689:Oncogene Protein p21(ras) / Q000235:genetics / Q000276:immunology*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*; D014611:Vaccination
chemical_list: D015395:Histocompatibility Antigens Class I; D004247:DNA; D015689:Oncogene Protein p21(ras)