肺癌のびまん性肺線維化病態に関する研究　第2編　肺癌における末梢血インターロイキン 2 レセプターの検討

Interleukin-2 receptor (IL-2R) and lymphocyte subsets in peripheral blood were evaluated in patients with lung cancer. The level of sluble IL-2R (sIL-2R) in sera and the percentage of IL-2R positive lymphocytes in lung cancer patients were higher than that in normal subjects, but the lymphocytes reactivity to IL-2 was not different from that in normal subjects. There was no difference in the IL-2/IL-2R system of each histological type in patients with lung cancer. The serum sIL-2R level and the percentage of IL-2R positive lymphocytes increased in the advenced stage, but lymphocyte reactivity to IL-2 decreased. There was dissociation between expression of IL-2R and lymphocyte reactivity to IL-2 in lung cancer patients. Furthermore, serum sIL-2R level increased in relation to progression of fibrotic changes in lung cancer with interstitial pneumonia, although the percentage of IL-2R positive lymphocytes did not increase. Serum sIL-2R level showed no correlation with the percentage of IL-2R positive lymphocytes. These data suggest that the increased level of sIL-2R may be related to fibrotic changes in the lung and reflect the disorder of cellular immunity in lung cancer patients with interstitial pneumonia.