Removal of sialic acid, galactose, or both was compared with the impact of fucose levels on MNC- or PMN-mediated ADCC by 2F8. To analyze the contribution of sialic acid, galactose and fucose levels to MNC- or PMN-mediated tumor cell killing, ADCC experiments with nonsialylated and degalactosylated in comparison to mock-treated 2F8 batches were performed. (A,B) Contribution of sialic acid. (C,D) Contribution of galactose. (E,F) Contribution of sialic acid and galactose (in combination). (G,H) Contribution of fucose. ADCC experiments were performed as described in “ADCC assays.” Compared batches are indicated, with glycosylation status in brackets. Data from experiments with at least 3 different donors are presented as means plus or minus SEM. *Significant differences in killing between batches (P < .05).