Kaplan-Meier survival plot of karpas299 lymphoma-bearing SCID/NOD wild-type and SCID/NOD FcRγ^–/– mice treated with HeFi-1 and daclizumab. (A) SCID/NOD wild-type mice (n = 15). (B) SCID/NOD FcRγ^–/– mice (n = 10-12). Treatment with daclizumab prolonged the survival of karpas299 lymphoma-bearing SCID/NOD wild-type mice significantly when compared with the control group (P < .01). However, the therapeutic efficacy of daclizumab was lost in karpas299 lymphoma-bearing SCID/NOD FcRγ^–/– mice. In contrast, HeFi-1 showed a similar therapeutic efficacy in SCID/NOD wild-type as compared to SCID/NOD FcRγ^–/– mice bearing the karpas299 lymphoma. The lymphoma-bearing mice in HeFi-1 treatment groups had a significantly prolonged survival when compared with mice in the control groups (P < .01).