TRI: Corroding Its Original Intent?

The recognition that T cell growth factor (TCGF) can maintain T cells in long-term culture offers the opportunity of expanding populations of monoclonal antigen-specific T lymphocytes with helper, suppressor or cytotoxic activity (Fathman & Fitch, 1982). The application of this technology in the generation of tumour reactive T cells for the analysis of tumour antigen recognition and their therapeutic potential in the management of malignant disease has evoked much investigation. Indeed, human T cell lines reactive against solid tumours (Vanky et al., 1982; Kedar et al., 1983) and tumour cell lines (Zarling & Bach, 1979; Mitsuya et al., 1983) have been propagated in culture with TCGF. For the most part these were derived from the cocultivation of tumour and lymphoid cells and resulted in the induction of T cell lines with cytotoxic activity. The aim of this study was to analyze the hetero-geneity of specificity of the T cell response in the peripheral blood of a patient who had a lobectomy for a pulmonary adenocarcinoma. Oligoclonal human T lymphocyte lines were induced with auto-logous pulmonary adenocarcinoma cells. Briefly, peripheral blood lymphocytes taken 3 weeks post operatively (PBL; 2.5 x 105 ml-1) were stimulated for 6 days in the absence of TCGF with a detergent extract (0.5% NP-40, BDH) of autologous tumour (10/Mgml-1) which contains solubilized membrane and cytoplasm. The antigen concentration required to produce optimal stimulation had been determined previously. Concentrations of the extract expressed as /ug ml-1 are based on the protein content determined by OD280. Viable cells from these cultures were isolated on a Ficoll-Hypaque density gradient and the lymphoblasts (20% of the viable cells) were resuspended in RPMI-1640 medium (Gibco, Grand Island, NY) supplemented with 10% pooled A' serum and 20% TCGF and plated at 3 cells well-I in microtest II trays (Falcon) with 104 irradiated (30 Gy) auto-logous PBL and tumour extract (10 yg ml-1) as previously described (Lamb et al., 1982a). TCGF was prepared by culturing PBL (106ml) with 0.1% purified phytohaemagglutinin (PHA-P; Difco) in the presence of 2.5% pooled A' serum. After 48 h supernatants were collected and assayed for their ability to support the growth of a TCGF dependent line. Growing lines were expanded with the addition of fresh TCGF every 3-4 days and with pooled irradiated allogeneic PBL (5 x IO' ml 1) as "filler" cells every 7 days. Since the plating efficiency was 3.4% it is possible that clonal populations of …