Lung natural killer and interleukin-2 activity in lung cancer. A pulmonary compartment of augmented natural killer activity occurs in patients with bronchogenic carcinoma.

Studies were performed to determine if natural killer (NK) cell and interleukin-2 (IL-2) activities are increased in lungs that harbor malignancy. The NK activity (ability to lyse 51Cr-K562 cells) in bronchoalveolar lavage mononuclear cells (BAC) and washed whole blood cells (Blood) was measured in 8 patients with bronchogenic carcinoma and 8 healthy control subjects. The mean NK activity by BAC from the patients with bronchogenic carcinoma was 2.81 lytic units, and from the control subjects it was 0.19 lytic units (p less than 0.001). When the data were expressed as a ratio of NK activity for BAC/Blood, the mean ratio was 0.98 in patients with cancer compared with 0.12 in control subjects (p less than 0.003). IL-2 activity was bioassayed in recovered bronchoalveolar lavage fluid (BAL) using 3H-thymidine uptake by IL-2-dependent T-cells. The concentration of IL-2 was expressed as units per microgram albumin and also as units multiplied by a dilution factor. The median concentration of IL-2 in BAL from the patients with bronchogenic carcinoma was 10.5 units x 10(-3)/micrograms albumin (range, 3.7 to 229), and from the healthy control subjects it was 0.37 units x 10(-3)/micrograms albumin (range 0.26 to 0.70) (p less than 0.001). When IL-2 activity was expressed as total number of IL-2 units in recovered lavage fluid times a dilution factor (volume of saline used for lavage/volume of lavage fluid recovered), the median number of IL-2 units was 4.7 for the patients with bronchogenic carcinoma and 0.085 for the control subjects (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)