title: Quantitative TCR:pMHC Dissociation Rate Assessment by NTAmers Reveals Antimelanoma T Cell Repertoires Enriched for High Functional Competence.
abstract: Experimental models demonstrated that therapeutic induction of CD8 T cell responses may offer protection against tumors or infectious diseases providing that T cells have sufficiently high TCR/CD8:pMHC avidity for efficient Ag recognition and consequently strong immune functions. However, comprehensive characterization of TCR/CD8:pMHC avidity in clinically relevant situations has remained elusive. In this study, using the novel NTA-His tag-containing multimer technology, we quantified the TCR:pMHC dissociation rates (koff) of tumor-specific vaccine-induced CD8 T cell clones (n = 139) derived from seven melanoma patients vaccinated with IFA, CpG, and the native/EAA or analog/ELA Melan-A(MART-1)(26-35) peptide, binding with low or high affinity to MHC, respectively. We observed substantial correlations between koff and Ca(2+) mobilization (p = 0.016) and target cell recognition (p < 0.0001), with the latter independently of the T cell differentiation state. Our strategy was successful in demonstrating that the type of peptide impacted on TCR/CD8:pMHC avidity, as tumor-reactive T cell clones derived from patients vaccinated with the low-affinity (native) peptide expressed slower koff rates than those derived from patients vaccinated with the high-affinity (analog) peptide (p < 0.0001). Furthermore, we observed that the low-affinity peptide promoted the selective differentiation of tumor-specific T cells bearing TCRs with high TCR/CD8:pMHC avidity (p < 0.0001). Altogether, TCR:pMHC interaction kinetics correlated strongly with T cell functions. Our study demonstrates the feasibility and usefulness of TCR/CD8:pMHC avidity assessment by NTA-His tag-containing multimers of naturally occurring polyclonal T cell responses, which represents a strong asset for the development of immunotherapy.
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and.
authors.forename: Philippe O
authors.initials: PO
authors.lastname: Gannon
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Wieckowski
authors.affiliation: Ludwig Center for Cancer Research, University of Lausanne, CH-1011 Lausanne, Switzerland.
authors.forename: Petra
authors.initials: P
authors.lastname: Baumgaertner
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and.
authors.forename: Michaël
authors.initials: M
authors.lastname: Hebeisen
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and.
authors.forename: Mathilde
authors.initials: M
authors.lastname: Allard
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and Ludwig Center for Cancer Research, University of Lausanne, CH-1011 Lausanne, Switzerland.
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Speiser
authors.affiliation: Department of Oncology, Lausanne University Hospital and University of Lausanne, CH-1011 Lausanne, Switzerland; and Ludwig Center for Cancer Research, University of Lausanne, CH-1011 Lausanne, Switzerland Nathalie.Rufer@unil.ch.
authors.forename: Nathalie
authors.initials: N
authors.lastname: Rufer
mesh_terms: D000951:Antigens, Neoplasm / Q000737:chemistry / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology*; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000737:chemistry / Q000276:immunology*; D002454:Cell Differentiation; D002999:Clone Cells; D003602:Cytotoxicity, Immunologic; D015234:HLA-A Antigens / Q000737:chemistry / Q000276:immunology; D006801:Humans; D007114:Immunization; D007700:Kinetics; D008545:Melanoma / Q000737:chemistry / Q000276:immunology* / Q000473:pathology / Q000628:therapy; D009362:Neoplasm Metastasis; D009367:Neoplasm Staging; D009942:Organometallic Compounds / Q000737:chemistry; D010455:Peptides / Q000737:chemistry / Q000276:immunology*; D011446:Prospective Studies; D011485:Protein Binding; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000737:chemistry / Q000276:immunology*; D012878:Skin Neoplasms / Q000737:chemistry / Q000276:immunology* / Q000473:pathology / Q000628:therapy
chemical_list: D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D015234:HLA-A Antigens; D009942:Organometallic Compounds; D010455:Peptides; D016693:Receptors, Antigen, T-Cell, alpha-beta