RIT of BCL₁ lymphoma using a panel of anti–B-cell mAbs. BCL₁ cells (10⁵ intravenously) were given on day 0, and RIT treatments were administered by intravenous injection 10 days later (500 μg mAbs with or without 9.25 MBq conjugated ¹³¹I). Unlabeled anti-MHCII had no discernible therapeutic effect and anti-Id and anti-CD19 had very modest improvements in survival of just a few days. A similar therapeutic effect was seen for all 3 radioimmunconjugates (9.25MBq ¹³¹I-labeled anti-MHCII, anti-CD19, and anti-Id).