Biodistribution properties of 111indium-labeled C-functionalized trans-cyclohexyl diethylenetriaminepentaacetic acid humanized 3S193 diabody and F(ab′)2 constructs in a breast carcinoma xenograft model

Abstract

The humanized complementarity determining region-grafted anti-Lewis Y (Ley) monoclonal antibody [humanized 3S193 (hu3S193) was developed for targeting Ley-expressing epithelial tumors such as breast, colon, lung, prostate, and ovarian carcinoma. We are exploring the potential use of smaller molecular size, bivalent analogues of hu3S193, because the faster blood clearance of Mr ∼54, 000 diabody and Mr ∼110, 000 F(ab′)2 molecules may be advantageous in achieving optimal and rapid tumor uptake for diagnostic and potential therapeutic applications. The single-chain variable fragment-5 residue linker construct (diabody) was expressed using the bacterial secretion vector pPOW3, and soluble product..