Cytotoxic activity of TIL from three patients with CTCL. TIL were cultured with IL-2 and IL-7, and were tested at day 10 for their ability to exhibit specific cytotoxic activity against the cells of the tumor specimen previously frozen. For the three patients, the TIL cultures exhibited a specific cytotoxic activity against autologous tumor T-cells (▪) whereas no cytotoxic activity was found on allogeneic tumor T cells (•). Results are expressed as the mean of triplicates ± SD.