INDUCTION OF KILLER-CELLS FROM LYMPHOCYTES IN PLEURAL EFFUSION OF ADVANCED LUNG-CANCER PATIENTS

We analyzed the phenotype and cytotoxic ability of pleural exudative lymphocytes (PLEL) which were obtained from 18 advanced lung cancer patients. Freshly isolated PLEL were mainly CD4(+) T cells and had weak natural killer, autologous tumor killing and lymphokine‐activated killer activities. After cultivation of PLEL with interleukin‐2, cytotoxicity of PLEL against autologous tumor cells was increased at 2 weeks, but it was remarkably reduced at 4 weeks. When PLEL were stimulated by mitomycin C‐treated autologous tumor cells during culture, autologous tumor killing activity of PLEL was significantly enhanced even after 4 weeks of cultivation. Cold target inhibition analysis and binding inhibition assays using monoclonal antibodies indicated that autologous tumor stimulation could induce major histocompatibility complex class I restricted cytotoxic T lymphocytes specific for autologous tumor cells in some cases. © 1990 Japanese Cancer Association