Marrow-to-normal organ ratios for conventional RIT with (A) ¹²⁵I-anti-mCD45 DOTA-Ab and (B) PRIT with ¹¹¹In-DOTA-biotin using an anti-mCD45 Ab-SA conjugate. Leukemic SJL/J mice were treated as described in Figures 2 and 4. Marrow-to-normal organ ratios of radioactivity using either (A) directly labeled ¹²⁵I-DOTA-Ab or (B) pretargeted ¹¹¹In-DOTA-biotin, delivered with or without CA at 8 hours, are shown 24 and/or 48 hours after injection of radioactivity. Error bars are SD.