Pharmacokinetics of ¹²⁵I-labeled HaaT, CD28.3 Ab Fab fragments, and scFv28.3-HaaT in mice. Purified sc28.3-HaaT, HaaT, and CD28.3 Fab fragments were labeled with ¹²⁵I and injected intravenously into mice. Blood samples were collected periodically and radioactivity was measured with a gamma counter. %ID indicates percent injected dose; ▪, scFv28.3-HaaT; ○, HaaT; and ⋄, Fab. For each, n = 3. Data are presented as means ± SDs.