Abstract
Mononuclear cells in 30 patients with esophageal cancer, resectable cases 21 and nonresectable cases 9, were harvested from peripheral blood by Ficoll Hypaque gradient. Peripheral blood mononuclear cells (PBMC) were incubated with rIL-2 for 5 days. After incubation, sensitivity of these cells for rIL-2 was examined by LAK activity and cell proliferation. PBMC in patients with esophageal cancer exhibited 48.1±25.2% in cytotoxicity against NK sensitive tumor cell, K 562, while PBMC in healthy donors did 64.5±8.8%. In regard to LAK activity against NK resistant tumor cell, Raji, 18.9±18.2% in patients with esophageal cancer was significantly lower than 29.2±14.9% in healthy donors (p<0.05).
Cell proliferation rate after incubation with rIL-2 was calculated by deviding post-incubated cell number by preincubated. Cell proliferation rate in patients with esophageal cancer was 53.2±30.2%, while that in healthy donors was 93.8±49.3%.
Moreover, nonadherent cells, acquired by removing adherent cells from PBMC by means of adherence to plastic dish, displayed higher LAK activity and cell proliferation rate after incubation with rIL-2 than PBMC.
The ratio (L/M) of number of peripheral lymphocytes (L) to monocytes (M) was compared between patients with esophageal cancer and early gastric cancer. L/M in patients with esophageal cancer was significantly lower than with early gastric cancer (p<0.01).
We suggested that sensitivity of PBMC in patients with esophageal cancer for rIL-2, LAK induction and cell proliferation, was depressed due to increase of monocytes in PBMC, whereas sensitivity of lymphocytes itself for rIL-2 was preserved to some degree.
