Interleukin-2 (IL-2) production by stimulated peripheral blood lymphocytes (PBL) from patients with lung cancer and noncancerous respiratory diseases was determined. The results are as follows:
1) Neither sex nor age difference was observed for IL-2 production among healthy people.
2) IL-2 production showed a positive correlation with the Leu-3a/Leu-2a ratio and a negative correlation with the percentage of HLA-DR+ cells.
3) IL-2 production of patients with lung cancer and noncancerous respiratory diseases did not differ from that of healthy persons.
4) No difference in IL-2 production was found in relation to the clinical stage of lung cancer, but subjects with low IL-2 production were mostly observed in the advanced stage group (Stage IV).