[Effect of cancerous ascites on natural killer activity].
The effect of cancerous ascites on NK activity was evaluated by a 12-hr exposure method. Erythroleukemia cell line, K 562, was used as the target cells, the effector cells were isolated from 34 healthy volunteers. The final protein concentration of ascites was adjusted to 0.02, 0.2 and 2.0 mg/ml, after centrifugation and membrane filtration. When ascites was added at the start of assay, NK activity was almost completely suppressed by cancerous ascites of 2.0 mg/ml; it was not suppressed by 0.02, 0.2 mg/ml. No suppression was found when cancerous ascites was added 6 hrs after the start of assay. Our results suggest that the lowered NK activity of cancer patients may be attributable to unknown factor (s) released from cancer cells.
D001201:Ascites / Q000276:immunology; D001202:Ascitic Fluid / Q000276:immunology*; D003602:Cytotoxicity, Immunologic; D006801:Humans; D007108:Immune Tolerance; D007694:Killer Cells, Natural / Q000276:immunology*; D010534:Peritoneal Neoplasms / Q000276:immunology*