Effect of cianidanol (KB-53) on the activity of mouse natural killer cells.

The effect of cianidanol (KB-53) on the mouse natural killer (NK) cell activity of the splenic cells was investigated using YAC-1 cells as target cells. The oral administration of KB-53 at a dose of 500 mg/kg augmented significantly the NK cell activity. The activity was observed maximally 3 d after the administration, and significant difference from the control was observed even at 7 d after the administration of KB-53. The oral administration of KB-53, at a dose range of 125-500 mg/kg, augmented the NK cell activity in a dose-dependent manner at 3 d after the administration.