Reconstitution of CD8+ T Cells by Retroviral Transfer of the TCR αβ-Chain Genes Isolated from a Clonally Expanded P815-Infiltrating Lymphocyte

Abstract

Gene transfer of TCR αβ-chains into T cells may be a promising strategy for providing valuable T lymphocytes in the treatment of tumors and other immune-mediated disorders. We report in this study the reconstitution of CD8+ T cells by transfer of TCR αβ-chain genes derived from an infiltrating T cell into P815. Analysis of the clonal expansion and Vβ subfamily usage of CD8+ TIL in the tumor sites demonstrated that T cells using Vβ10 efficiently infiltrated and expanded clonally. The TCR α- and β-chain sequences derived from a tumor-infiltrating CD8+/Vβ10+ single T cell clone (P09-2C clone) were simultaneously determined by the RT-PCR/single-strand conformational polymorphism method and the single-cell PCR method. When P09-2C TCR αβ-chain genes were retrovirally introduced into CD8+ T cells, the reconstituted T cells positively lysed the P815 tumor cells, but not the A20, EL4, or YAC-1 cells, in vitro. In addition, the CTL activity was blocked by the anti-H2Ld mAb. Furthermore, T cells containing both TCR α- and β-chains, but not TCR β-chain alone, accumulated at the tumor-inoculated site when the reconstituted CD8+ T cells were adoptively transferred to tumor-bearing nude mice. These findings suggest that it is possible to reconstitute functional tumor-specific CD8+ T cells by transfer of TCR αβ-chain genes derived from TIL, and that such T cells might be useful as cytotoxic effector cells or as a vehicle for delivering therapeutic agents.