title: Generation of CD20-specific TCRs for TCR gene therapy of CD20low B-cell malignancies insusceptible to CD20-targeting antibodies.
abstract: Immunotherapy of B-cell leukemia and lymphoma with CD20-targeting monoclonal antibodies (mAbs) has demonstrated clinical efficacy. However, the emergence of unresponsive disease due to low or absent cell surface CD20 urges the need to develop additional strategies. In contrast to mAbs, T-cells via their T-cell receptor (TCR) can recognize not only extracellular but also intracellular antigens in the context of HLA molecules. We hypothesized that T-cells equipped with high affinity CD20-targeting TCRs would be able to recognize B-cell malignancies even in the absence of extracellular CD20. We isolated CD8+ T-cell clones binding to peptide-MHC-tetramers composed of HLA-A*02:01 and CD20-derived peptide SLFLGILSV (CD20SLF) from HLA-A*02:01neg healthy individuals to overcome tolerance towards self-antigens such as CD20. High avidity T-cell clones were identified that readily recognized and lysed primary HLA-A2pos B-cell leukemia and lymphoma in the absence of reactivity against CD20-negative but HLA-A2pos healthy hematopoietic and nonhematopoietic cells. The T-cell clone with highest avidity efficiently lysed malignant cell-lines that had insufficient extracellular CD20 to be targeted by CD20 mAbs. Transfer of this TCR installed potent CD20-specificity onto recipient T-cells and led to lysis of CD20low malignant cell-lines. Moreover, our approach facilitates the generation of an off-the-shelf TCR library with broad applicability by targeting various HLA alleles. Using the same methodology, we isolated a T-cell clone that efficiently lysed primary HLA-B*07:02pos B-cell malignancies by targeting another CD20-derived peptide. TCR gene transfer of high affinity CD20-specific TCRs can be a valuable addition to current treatment options for patients suffering from CD20low B-cell malignancies.
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Lorenz
authors: L
authors: Jahn
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Dirk M
authors: DM
authors: van der Steen
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Renate S
authors: RS
authors: Hagedoorn
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.|Department of Hematopoiesis, Sanquin Research, 1006 AD Amsterdam, The Netherlands.
authors: Pleun
authors: P
authors: Hombrink
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Michel G D
authors: MG
authors: Kester
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Marjolein P
authors: MP
authors: Schoonakker
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Daniëlle
authors: D
authors: de Ridder
authors: Department of Immunohematology and Blood Transfusion, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.|Center for Proteomics and Metabolomics, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Peter A
authors: PA
authors: van Veelen
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: J H Frederik
authors: JH
authors: Falkenburg
authors: Department of Hematology, Leiden University Medical Center, 2300 RC Leiden, The Netherlands.
authors: Mirjam H M
authors: MH
authors: Heemskerk
mesh_terms: D018951:Antigens, CD20 / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D015316:Genetic Therapy; D015789:HLA-A2 Antigen / Q000276:immunology; D006801:Humans; D020014:K562 Cells; D015448:Leukemia, B-Cell / Q000235:genetics / Q000276:immunology / Q000628:therapy*; D016393:Lymphoma, B-Cell / Q000235:genetics / Q000276:immunology / Q000628:therapy*; D011948:Receptors, Antigen, T-Cell / Q000235:genetics* / Q000276:immunology
chemical_list: D018951:Antigens, CD20; D015789:HLA-A2 Antigen; D011948:Receptors, Antigen, T-Cell
keywords: B-cell leukemia and lymphoma; CD20; TCR gene transfer; immunotherapy; monoclonal antibodies