Lysis of human T-cell blasts with human complement.

(♦, BM^WT), bivalent^WT monomer; (■, 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 complement is indicated (NC).