Tetramer-guided analysis of TCR β-chain usage reveals a large repertoire of melan-A-specific CD8+ T cells in melanoma patients

D Valmori, V Dutoit, D Liénard, F Lejeune… - The Journal of …, 2000 - journals.aai.org
D Valmori, V Dutoit, D Liénard, F Lejeune, D Speiser, D Rimoldi, V Cerundolo, PY Dietrich…
The Journal of Immunology, 2000journals.aai.org
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 β-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 …
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 β-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.
journals.aai.org