Pharmacokinetics and blood clearance of Ab/SA conjugates. (A) Whole blood clearance of 1.4 nmol of either ¹²⁵I-labeled 1F5/SA (●), Lym-1/SA (○) or HD39/SA (◇) injected intravenously into athymic BALB/c mice (n = 4/group). (B-D) The effect of the NAGB CA on circulating levels of each of the Ab/SA conjugates: 1F5/SA (B), Lym-1/SA (C), and HD39/SA (D). Athymic BALB/c mice (n = 4/group) were injected intravenously at t = 0 with 1.4 nmol ¹²⁵I-labeled conjugate followed 24 hours later with an intravenous injection of 5.8 nmol CA. In each study, serial blood samples were obtained from the retro-orbital venous plexus and radiation levels present determined by γ-counting and percent injected dose/gram (%ID/g) calculated.