Comparison of the natural cell mediated and antibody dependent cell mediated cytotoxicity measured as a function of target cell number in patients with mammary tumors and healthy female blood donors.

Peripheral blood lymphocytes of 84 patients with mammary tumors (73 malignant, 11 benign diseases) and 79 healthy female blood donors were tested in three cytotoxicity assays. Natural cell mediated cytotoxicity (NCMC) was measured against K562 cell line, antibody dependent cellular cytotoxicity (ADCC) was tested against K562 cell line sensitized with hyperimmune rabbit anti K562 sera and human 0, Rh positive (C, D, E pos.) erythrocytes sensitized with Ripley antibodies. Effector cell activity was measured as a function of the target cell number in the new cytotoxic capacity test. Maximums were determined experimentally and also by extrapolation from the measured values using the Michaelis-Menten equation. It was found, that activity of patients was lower than that of the controls in all the three tests already at an early stage of the malignant disease. Therefore introduction of the new cytotoxic capacity test to screen NCMC and ADCC is suggested.