Proliferation and expansion of 14.G2a-ζ–transduced CTLs.

(A) 14.G2a-ζ–transduced CTLs proliferate in response to EBV but not tumor targets. 14.G2a-ζ–transduced (CTL/chRec) and nontransduced EBV-specific CTLs (CTL/NT) were stimulated with irradiated (40 Gy) autologous or mismatched allogeneic LCLs, or with G$D2+$ (LAN-1) or G$D2−$ (A-204) tumor cells at a 1:4 stimulator-to-responder ratio. Proliferative responses were assessed by measurement of [³H]-thymidine uptake. (B) 14.G2a-ζ–transduced CTLs expand in response to EBV but not tumor targets. EBV-specific CTL cultures, either nontransduced or transduced with the chimeric receptor gene 14.G2a-ζ or with a control gene encoding enhanced green fluorescent protein (EGFP), received weekly stimulations with irradiated (40 Gy) autologous LCL or G$D2+$ tumor cell targets at a 1:4 stimulator-to-responder ratio. Cells were fed twice weekly with medium containing rhIL-2 (40 IU/mL), and their growth was assessed. A representative experiment (of 4) is shown.