Affinity, specificity and T-cell-receptor diversity of melanoma-specific CTL generatedin vitro against a single tyrosinase epitope

Abstract

MHC‐class‐I‐restricted cytotoxic T lymphocytes (CTL) specific for tumor‐associated antigens expressed by malignant cells are important components of the immune response against cancer. Recently, tumor‐specific CTL could be generated in vitro, with responding lymphocytes from the blood of healthy blood donors. In the present study, we confirm that peptide‐specific stimulation in vitro can induce high‐affinity CTL capable of recognizing tumor cells expressing the appropriate tumor antigen. These tyrosinase‐specific CTL display a restricted usage of TCRAV and TCRBV gene segments but of diverse CDR3 regions, resulting in a distinct fine‐specificity for each CTL clone. This suggests that, similar to in vivo priming, peptide‐pulsed APC are capable of stimulating a T‐cell response in vitro expressing a limited TCR repertoire against autologous tumors. The generated CTL can recognize their target structure with high affinity, and this correlates in part with tumor‐cell lysis. This methodology may be used to treat melanoma patients with infusion of ex vivo‐induced and ‐expanded CTL. Int. J. Cancer 72:1122–1128, 1997. © 1997 Wiley‐Liss, Inc.

Peptide Fine Specificity of Anti-Glycoprotein 100 CTL Is Preserved Following Transfer of Engineered TCRαβ Genes Into Primary Human T Lymphocytes

“…This notion is further supported by the crystal structure of a TCR bound to a viral peptide/HLA-A2 complex (40). Although several studies show that conservation of sequence and size of CDR3␤ of CTL is not an absolute determinant of Ag recognition, TCR CDR3 regions do appear to govern peptide fine specificity of CTL (41,42).…”

First Comparative Delineation of the T Cell Receptor Repertoire in Primary and Multiple Subsequent/Coexisting Metastatic Melanoma Sites

“…As functional data are lacking, no definitive decision can be made whether this combination of highly conserved BVJ gene segment combinations in the context of heterogeneous CDR3 regions within coexisting melanoma sites is indicative of the occurrence of functionally unrelated TCR specificities, which were generated by random mutations in rapidly growing melanoma cells, or, alternatively, results from the recognition of related epitopes of a restricted number of MAA. Support for the latter assumption comes from a manuscript by Visseren et al (1997), who found that in vitro priming of PBL from healthy donors with the tyrosinase 369-377 peptide can induce peptidespecific CTL that, despite a restricted usage of AV and BV gene segments, exhibit a considerable diversity in their CDR3 regions resulting in a distinct lytic fine specificity of each clonotype.…”

Effect of B7.1-transfected human colon cancer cells on the induction of autologous tumour-specific cytotoxic T cells

“…The importance of the immune response, particularly T cell‐mediated cytotoxicity, in the anti‐tumour response was demonstrated by the presence of several T cell repertoires with the ability to kill autologous tumours in local tissues 17–20 and by the generation of tumour specific CTL clones from PBMC in human cancer patients. 21,22 We have previously reported that autologous liver cancer‐specific CTL can be induced by stimulation with autologous tumours together with IL‐2 and that these CTL had a potent therapeutic effect on several liver cancer patients. 23 However, all previous clinical trials including ours have demonstrated that the effect of these adoptive immunotherapies was limited.…”

“… 23 However, all previous clinical trials including ours have demonstrated that the effect of these adoptive immunotherapies was limited. 17–23 Therefore, the development of more effective tools for adoptive immunotherapy is still urgently required. For this reason, we have attempted to establish a more potent in vitro system to induce autologous tumour‐specific CTL.…”