title: ALK as a novel lymphoma-associated tumor antigen: identification of 2 HLA-A2.1-restricted CD8+ T-cell epitopes.
abstract: Oncogenic anaplastic lymphoma kinase (ALK) fusion proteins (NPM/ALK and associated variants) are expressed in about 60% of anaplastic large cell lymphomas (ALCLs) but are absent in normal tissues. In this study, we investigated whether ALK, which is expressed at high levels in lymphoma cells, could be a target for antigen-specific cell-mediated immunotherapy. A panel of ALK-derived peptides was tested for their binding affinity to HLA-A*0201 molecules. Binding peptides were assessed for their capacity to elicit a specific immune response mediated by cytotoxic T lymphocytes (CTLs) both in vivo, in HLA-A*0201 transgenic mice, and in vitro in the peripheral blood lymphocytes (PBLs) from healthy donors. Two HLA-A*0201-restricted CTL epitopes, p280-89 (SLAMLDLLHV) and p375-86 (GVLLWEIFSL), both located in the ALK kinase domain were identified. The p280-89- and p375-86-induced peptide-specific CTL lines were able to specifically release interferon-gamma (IFN-gamma) on stimulation with ALK peptide-pulsed autologous Epstein-Barr virus-transformed B cells (LCLs) or T2 cells. Anti-ALK CTLs lysed HLA-matched ALCL and neuroblastoma cell lines endogenously expressing ALK proteins. CTL activity was inhibited by anti-HLA-A2 monoclonal antibody CR11.351, consistent with a class I-restricted mechanism of cytotoxicity. These results show the existence of functional anti-ALK CTL precursors within the peripheral T-cell repertoire of healthy donors, clearly indicating ALK as a tumor antigen and ALK-derived peptides, p280-89 and p375-86, as suitable epitopes for the development of vaccination strategies.
authors.affiliation: Oncogenic Fusion Genes and Proteins Unit, Istituto Nazionale per lo Studio e la Cura dei Tumori, Via Venezian 1, 20133 Milan, Italy. passoni@istitutotumori.mi.it
authors.forename: Lorena
authors.initials: L
authors.lastname: Passoni
authors.forename: Antonio
authors.initials: A
authors.lastname: Scardino
authors.forename: Carla
authors.initials: C
authors.lastname: Bertazzoli
authors.forename: Barbara
authors.initials: B
authors.lastname: Gallo
authors.forename: Addolorata M L
authors.initials: AM
authors.lastname: Coluccia
authors.forename: François A
authors.initials: FA
authors.lastname: Lemonnier
authors.forename: Konstadinos
authors.initials: K
authors.lastname: Kosmatopoulos
authors.forename: Carlo
authors.initials: C
authors.lastname: Gambacorti-Passerini
mesh_terms: D000077548:Anaplastic Lymphoma Kinase; D000818:Animals; D000951:Antigens, Neoplasm / Q000276:immunology*; D001665:Binding Sites / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D003602:Cytotoxicity, Immunologic; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D015789:HLA-A2 Antigen / Q000276:immunology / Q000378:metabolism; D006801:Humans; D007167:Immunotherapy / Q000379:methods; D051379:Mice; D008822:Mice, Transgenic; D010446:Peptide Fragments / Q000276:immunology / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000276:immunology*; D020794:Receptor Protein-Tyrosine Kinases; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D018984:Epitopes, T-Lymphocyte; D015789:HLA-A2 Antigen; D010446:Peptide Fragments; C000626173:ALK protein, human; C000626174:Alk protein, mouse; D000077548:Anaplastic Lymphoma Kinase; D011505:Protein-Tyrosine Kinases; D020794:Receptor Protein-Tyrosine Kinases