Table II.
Transduction of an IL-2 gene into cells with antitumor reactivity did not affect tumor recognition of transductantsa
| Effectors (IFN-γ pg/ml)
|
|||||
|---|---|---|---|---|---|
| Expt. 1 (sorted PBMC transductants)
|
Expt. 2 (P209 clones)
|
||||
| Targets | IL-2YFP | YFP | IL-2YFP #3 | YFP #29 | Expt. 3 (IL-2YFP transductants (proliferated in the no IL-2 condition)) |
| T2 pulsed with peptide | |||||
| MART-1 (1 μM) | 1 | 0 | 1 | 0 | 6 |
| 209 (1 μM) | >900 | >900 | 4255 | 1870 | >900 |
| 209 (0.01 μM) | 915 | 339 | |||
| 209 (0.0001 μM) | 23 | 3 | |||
| Tumors cell line | |||||
| 526 (A2+) | 1032 | 437 | |||
| 888 (A2−) | 3 | 2 | |||
| No targets | 2 | 6 | |||
Experiment 1: The indicated PBMC transductants (14 days after sorting and maintained in the presence of IL-2) were cocultured overnight with the targets as shown. IFN-γ release was determined by ELISA (>900 pg/ml offscale). Experiment 2: P209IL-2YFP and YFP clones were derived from transduced PBMCs as shown in experiment 1. These clones were expanded in a REP experiment in the presence of IL-2 and were assayed at day 10 of the REP for the IFN-γ release in an independent coculture experiment. The levels of the IFN-γ released were quantified by serial dilution of the coculture media in an ELISA. Experiment 3: cells were obtained from the no IL-2 condition (Fig. 4, middle) in a REP experiment on day 14. Antitumor T cells (4 × 104) were incubated with 1 × 105 T2 cells pulsed with peptides as shown. After overnight coculture, the IFN-γ released was assayed as described above (>900 offscale).