PBMCs cultured with cytokines: Relationship of the percentage of NK cells to the ADCC activity on days 1 and 7. Shown are the percentage of NK cells in PBMCs for each cytokine treatment group on day 1 (Panel A) and day 7 (Panel C), as well as the corresponding ADCC activities on target SK-MEL-28 cells for each treatment group on day 1 (Panel B) and day 7 (Panel D). The data are expressed as the mean % cytotoxicity mediated in the presence of 1 µg/ml KM871 of triplicate samples, with error bars denoting one standard deviation.