Coexpression of the T-cell receptor constant alpha domain triggers tumor reactivity of single-chain TCR-transduced human T cells.
Transfer of tumor antigen-specific T-cell receptors (TCRs) into human T cells aims at redirecting their cytotoxicity toward tumors. Efficacy and safety may be affected by pairing of natural and introduced TCRalpha/beta chains potentially leading to autoimmunity. We hypothesized that a novel single-chain (sc)TCR framework relying on the coexpression of the TCRalpha constant alpha (Calpha) domain would prevent undesired pairing while preserving structural and functional similarity to a fully assembled double-chain (dc)TCR/CD3 complex. We confirmed this hypothesis for a murine p53-specific scTCR. Substantial effector function was observed only in the presence of a murine Calpha domain preceded by a TCRalpha signal peptide for shuttling to the cell membrane. The generalization to a human gp100-specific TCR required the murinization of both C domains. Structural and functional T-cell avidities of an accessory disulfide-linked scTCR gp100/Calpha were higher than those of a dcTCR. Antigen-dependent phosphorylation of the proximal effector zeta-chain-associated protein kinase 70 at tyrosine 319 was not impaired, reflecting its molecular integrity in signaling. In melanoma-engrafted nonobese diabetic/severe combined immunodeficient mice, adoptive transfer of scTCR gp100/Calpha transduced T cells conferred superior delay in tumor growth among primary and long-term secondary tumor challenges. We conclude that the novel scTCR constitutes a reliable means to immunotherapeutically target hematologic malignancies.
Voss
Ralf-Holger
RH
Department of Hematology and Oncology, University Medical Center, Mainz, Germany. hvoss@uni-mainz.de
Thomas
Simone
S
Pfirschke
Christina
C
Hauptrock
Beate
B
Klobuch
Sebastian
S
Kuball
Jürgen
J
Grabowski
Margarete
M
Engel
Renate
R
Guillaume
Philippe
P
Romero
Pedro
P
Huber
Christoph
C
Beckhove
Philipp
P
Theobald
Matthias
M
D019264:Adoptive Transfer; D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D045744:Cell Line, Tumor; D006801:Humans; D007111:Immunity, Cellular; D008545:Melanoma / Q000235:genetics / Q000276:immunology / Q000378:metabolism / Q000628:therapy*; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D009368:Neoplasm Transplantation; D010766:Phosphorylation / Q000235:genetics; D017434:Protein Structure, Tertiary; D016693:Receptors, Antigen, T-Cell, alpha-beta / Q000096:biosynthesis / Q000235:genetics / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology* / Q000378:metabolism / Q000637:transplantation; D014161:Transduction, Genetic; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism
D000951:Antigens, Neoplasm; D016693:Receptors, Antigen, T-Cell, alpha-beta; D016159:Tumor Suppressor Protein p53