ADCC of human PBMCs by homologous CD56⁺effector cells.

(■, BM), bivalent^Cys444 monomer; (▵, BD), bivalent^Cys444 dimer; (○, MM), monovalent^Cys444 monomer; (×, MD), monovalent^Cys444 dimer; (⋄, alem), CD52 mAb alemtuzumab. Each point is the mean of duplicate tests. The range of lysis observed with all mAbs at their maximum test concentration in the absence of effector cells (NE) and the level of lysis given by effector cells in the absence of mAb (NA) are indicated.