title: Identification of wild-type and mutant p53 peptides binding to HLA-A2 assessed by a peptide loading-deficient cell line assay and a novel major histocompatibility complex class I peptide binding assay.
abstract: Mutations of the p53 gene are the most frequently observed genetic changes in human cancers; often leading to an overexpression of the wild-type (wt) p53 protein. Demonstrable T cell reactivity against tumor cells overexpressing wt or mutant p53-derived peptides could support the application of such epitopes in cancer immunotherapies. As the binding of peptide to MHC class I molecules is a prerequisite for antigen-specific T cell recognition, we evaluated the ability of wt and mutant p53 peptides to bind to HLA-A2.1 using two independent flow cytometry-based assay systems, the T2 major histocompatibility complex (MHC) class I peptide stabilization assay (stabilization assay) and the peptide-induced MHC class I reconstitution assay (reconstitution assay). The twenty selected wt sequences each conformed to the previously reported HLA-A2.1 peptide binding motif. Seven of the wt p53 and 2/13 mutant p53 peptides derived from the previously chosen wt peptides bound to HLA-A2.1 in both the stabilization and the reconstitution assays. An additional six wt and six mutant p53 peptides, presumably exhibiting lower affinity for HLA-A2.1, were identified only in the reconstitution assay. Those p53 peptides binding HLA-A2.1 may provide useful immunogens for the generation of HLA-A2.1-restricted cytolytic T lymphocytes in vitro and in vivo.
authors.affiliation: Department of Tumor Biology, Karolinska Institute, Stockholm.
authors.forename: G
authors.initials: G
authors.lastname: Stuber
authors.forename: G H
authors.initials: GH
authors.lastname: Leder
authors.forename: W T
authors.initials: WT
authors.lastname: Storkus
authors.forename: M T
authors.initials: MT
authors.lastname: Lotze
authors.forename: S
authors.initials: S
authors.lastname: Modrow
authors.forename: L
authors.initials: L
authors.lastname: Székely
authors.forename: H
authors.initials: H
authors.lastname: Wolf
authors.forename: E
authors.initials: E
authors.lastname: Klein
authors.forename: K
authors.initials: K
authors.lastname: Kärre
authors.forename: G
authors.initials: G
authors.lastname: Klein
mesh_terms: D000595:Amino Acid Sequence; D002460:Cell Line; D015789:HLA-A2 Antigen / Q000276:immunology*; D006801:Humans; D008969:Molecular Sequence Data; D010455:Peptides / Q000276:immunology*; D011485:Protein Binding; D013329:Structure-Activity Relationship; D016159:Tumor Suppressor Protein p53 / Q000737:chemistry / Q000276:immunology*
chemical_list: D015789:HLA-A2 Antigen; D010455:Peptides; D016159:Tumor Suppressor Protein p53