title: Specific recognition and inhibition of Ewing tumour growth by antigen-specific allo-restricted cytotoxic T cells.
abstract: BACKGROUND
  The development of a successful immunotherapy is hampered by an ineffective T-cell repertoire against tumour antigens and the inability of the patient's immune system to overcome tolerance-inducing mechanisms. Here, we test the specific recognition and lytical potential of allo-restricted CD8(+) T cells against Ewing tumour (ET) associated antigens Enhancer of Zeste, Drosophila Homolog 2 (EZH2), and Chondromodulin-I (CHM1) identified through previous microarray analysis.
  
  
  METHODS
  Following repetitive CHM1(319) (VIMPCSWWV) and EZH2(666) (YMCSFLFNL) peptide-driven stimulations with HLA-A 0201(+) dendritic cells (DC), allo-restricted HLA-A 0201(-) CD8(+) T cells were stained with HLA-A 0201/peptide multimers, sorted and expanded by limiting dilution.
  
  
  RESULTS
  Expanded T cells specifically recognised peptide-pulsed target cells or antigen-transfected cells in the context of HLA-A 0201 and killed HLA-A 0201(+) ET lines expressing the antigen while HLA-A 0201(-) ET lines were not affected. Furthermore, adoptively transferred T cells caused significant ET growth delay in Rag2(-/-)γ(C)(-/-) mice. Within this context, we identified the CHM1(319) peptide as a new candidate target antigen for ET immunotherapy.
  
  
  CONCLUSIONS
  These results clearly identify the ET-derived antigens, EZH2(666) and CHM1(319), as suitable targets for protective allo-restricted human CD8(+) T-cell responses against non-immunogenic ET and may benefit new therapeutic strategies in ET patients treated with allogeneic stem cell transplantation.
authors.affiliation: Laboratory for Functional Genomics and Transplantation Biology, Children's Cancer Research Center and Department of Pediatrics, 81664 München, Germany.
authors.forename: U
authors.initials: U
authors.lastname: Thiel
authors.forename: S
authors.initials: S
authors.lastname: Pirson
authors.forename: C
authors.initials: C
authors.lastname: Müller-Spahn
authors.forename: H
authors.initials: H
authors.lastname: Conrad
authors.forename: D H
authors.initials: DH
authors.lastname: Busch
authors.forename: H
authors.initials: H
authors.lastname: Bernhard
authors.forename: S
authors.initials: S
authors.lastname: Burdach
authors.forename: G H S
authors.initials: GH
authors.lastname: Richter
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology* / Q000378:metabolism; D001859:Bone Neoplasms / Q000276:immunology / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D002478:Cells, Cultured; D003602:Cytotoxicity, Immunologic / Q000276:immunology; D004268:DNA-Binding Proteins / Q000235:genetics; D015536:Down-Regulation; D006801:Humans; D016219:Immunotherapy, Adoptive; D007519:Isoantigens / Q000276:immunology* / Q000378:metabolism; D020014:K562 Cells; D051379:Mice; D018345:Mice, Knockout; D012512:Sarcoma, Ewing / Q000276:immunology / Q000473:pathology*; D037182:T-Cell Antigen Receptor Specificity / Q000276:immunology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology* / Q000378:metabolism
chemical_list: D000951:Antigens, Neoplasm; D004268:DNA-Binding Proteins; D007519:Isoantigens; C499308:Rag2 protein, mouse