In vitro differences in lymphocyte subpopulation reactivity in lung cancer patients: purified protein derivative-specific suppressor T lymphocytes in patients who have received Bacillus Calmette-Guerin.

Antigen-specific responses of lymphocyte to purified protein derivative (PPD) were studied in seven patients with non-small cell lung cancer who had undergone complete resection and received postoperative intrapleural Bacillus Calmette-Guerin. In addition, one patient with unresected lung cancer and reactive tuberculin skin test (PPD +) and five normal PPD- individuals were also studied. Lung cancer patients had significantly fewer responsive peripheral blood lymphocytes, unfractionated T cells, and T cells bearing Fc-IgG receptors (TG + populations) than normal controls. These deficits were most pronounced in the group who had received intrapleural Bacillus Calmette-Guerin but who had failed to develop reactive tuberculin skin tests. In contrast, the TG-populations (FC-IgG receptor-negative T cells) from all patients responded to PPD. TG + cells specifically inhibited TG- -cell responses to PPD in both proliferation and immunoglobulin secretion. Radiosensitive suppressor monocytes were found in other patients. This study shows interesting immune deficits in early lung cancer patients. These patients appear to have PPD-specific suppressor TG + cells which may contribute to the immune deficits in these patients.