Lymphokine-activated killer cell activity in lung cancer.

This study evaluates local pulmonary immune effector cell lytic activity. Purified lymphocyte populations were isolated from BALF obtained from 18 patients with bronchogenic carcinoma, six patients with lung disorders other than cancer, and ten normal control volunteers matched for age and smoking history. These cells were evaluated for NK and LAK cell lytic activity against NK-resistant LAK-sensitive tumor targets (A549 pulmonary tumor and Daudi tumor cells) and an NK-sensitive tumor (K562); LAK activity was detected in BALF from 6 of the 18 patients with cancer. The remaining patients with cancer, the subjects with pulmonary disease other than cancer, and the normal volunteers had no detectable lytic activity. Peripheral blood lymphocytes from all subjects had only NK lytic activity and did not kill the pulmonary tumor target; AMs were not tumoricidal. Interleukin-2, which is required for LAK cell activation, was detected only in BALF recovered from the six patients with pulmonary LAK lytic activity. These results demonstrate that activated LAK cells, capable of killing pulmonary tumor cells, are present in BALF of some patients with bronchogenic carcinoma. This lytic LAK cell population represents a local pulmonary response against the lung cancer in the absence of systemic tumoricidal activity. The functional status of pulmonary immune effector cells, as well as the type and quantities of cytokines in the lung determine local responsiveness to bronchogenic carcinoma and may well control the course of this disease.