title: Tetramer-guided analysis of TCR beta-chain usage reveals a large repertoire of melan-A-specific CD8+ T cells in melanoma patients.
abstract: The assessment of the TCR repertoire expressed by tumor-specific CD8+ T lymphocytes has been hampered to date by the difficulty of targeting the analysis to lymphocytes directed against a single epitope. In the present study we have used fluorescent A2/Melan-A tetramers in conjunction with anti-CD8 and anti-TCR beta-chain variable (BV) mAbs to analyze by flow cytometry the BV segment usage by Melan-A-specific CD8+ T cells in tumor-infiltrated lymph nodes (TILN) and tumor-infiltrating lymphocytes (TIL) from A2 melanoma patients. Analysis of TILN populations revealed small proportions of A2/Melan-A tetramer+ cells expressing many different BV together with over-representation of A2/Melan-A tetramer+ cells expressing certain BVs. The BV usage by A2/Melan-A tetramer+ lymphocytes in TIL was more restricted than that in TILN. Moreover, the predominant BV segments were quite distinct in populations derived from different patients. A2/Melan-A tetramer+ cells expressing the dominant BVs found in TILN could also be found in the corresponding peptide-stimulated autologous PBMC, although A2/Melan-A tetramer+ lymphocytes expressing additional BVs were also identified. Together, these results suggest that a large and diverse repertoire of Melan-A-specific T cells using different BV TCR segments is available in A2 melanoma patients.
authors.affiliation: Division of Clinical Onco-Immunology, Ludwig Institute for Cancer Research, Lausanne Branch, University Hospital, Switzerland. danila.valmori@inst.hospvd.ch
authors.forename: D
authors.initials: D
authors.lastname: Valmori
authors.forename: V
authors.initials: V
authors.lastname: Dutoit
authors.forename: D
authors.initials: D
authors.lastname: Liénard
authors.forename: F
authors.initials: F
authors.lastname: Lejeune
authors.forename: D
authors.initials: D
authors.lastname: Speiser
authors.forename: D
authors.initials: D
authors.lastname: Rimoldi
authors.forename: V
authors.initials: V
authors.lastname: Cerundolo
authors.forename: P Y
authors.initials: PY
authors.lastname: Dietrich
authors.forename: J C
authors.initials: JC
authors.lastname: Cerottini
authors.forename: P
authors.initials: P
authors.lastname: Romero
mesh_terms: D000328:Adult; D000368:Aged; D000951:Antigens, Neoplasm / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D018984:Epitopes, T-Lymphocyte / Q000378:metabolism*; D015333:Gene Rearrangement, beta-Chain T-Cell Antigen Receptor; D019674:Genes, T-Cell Receptor beta; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000276:immunology / Q000378:metabolism; D008213:Lymphocyte Activation / Q000276:immunology; D018655:Lymphocyte Count; D016246:Lymphocytes, Tumor-Infiltrating / Q000276:immunology / Q000378:metabolism / Q000473:pathology; D058965:MART-1 Antigen; D008545:Melanoma / Q000276:immunology* / Q000378:metabolism / Q000473:pathology; D008875:Middle Aged; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000276:immunology*; D010446:Peptide Fragments / Q000276:immunology; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D018984:Epitopes, T-Lymphocyte; D058965:MART-1 Antigen; C548667:MLANA protein, human; D009363:Neoplasm Proteins; D010446:Peptide Fragments