[Not Available].

The effect of ochratoxin A (OTA) and C (OTC) on the cytolytic activity of natural killer cells (NK cells) was studied using a fluorescence based bioassay with the cell line NK-92 as effector cell line and K-562 as target cell line. Different OTA and OTC preparations were included in the study. After exposure to very low toxin concentrations (1-10 ng/ml) a slight stimulation of NK cell activity was noted, whereas after addition of higher toxin concentrations (100-1000 ng/ml) NK cell function was suppressed. Preparations containing OTC showed a stronger effect than those containing OTA.