34-1-2s caused mortality only in SCID mice. Kaplan-Meier survival plot of SCID mice (n > 5 for each dose group) injected with the indicated does of 34-1-2s mAb. No mortality occurred in BALB/c mice (N = 21). Results are presented for SCID mice injected with 2.3 mg/kg (○), 4.5 mg/kg (□), 9.1 mg/kg (◊), or 22.7 mg/kg (▵) of 34-1-2s mAb.