Conjugation and radiolabeling of monoclonal antibodies with zirconium-89 for PET imaging using the bifunctional chelate p-isothiocyanatobenzyl-desferrioxamine

Abstract

The positron emitter zirconium-89 ((89)Zr) has very attractive properties for positron emission tomography (PET) imaging of intact monoclonal antibodies (mAbs) using immuno-PET. This protocol describes the step-by-step procedure for the facile radiolabeling of mAbs or other proteins with (89)Zr using p-isothiocyanatobenzyl-desferrioxamine (Df-Bz-NCS). First, Df-Bz-NCS is coupled to the lysine-NH(2) groups of a mAb at pH 9.0 (pre-modification), followed by purification using gel filtration. Next, the pre-modified mAb is labeled at room temperature by the addition of [(89)Zr]Zr-oxalic acid solution followed by purification using gel filtration. The entire process of pre-modification, radiolabeling and purification steps will take about 2.5 h.

89Zr-Nanocolloidal Albumin–Based PET/CT Lymphoscintigraphy for Sentinel Node Detection in Head and Neck Cancer: Preclinical Results

“…In the present study, we describe a method for efficient and inert labeling of nanocolloidal albumin with 89 Zr using the bifunctional desferal chelate Df-Bz-NCS, which was previously introduced for the coupling of 89 Zr to intact monoclonal antibodies (12,13). Stable 89 Zr-nanocolloidal albumin radiocolloid was produced using this method.…”

Siderophores for molecular imaging applications

“…For the coupling of DFO to antibodies, most widely 2,3,5,6 tetrafluorophenyl TFP-activated ester of Nsuccinyl-DFO-Fe forming stable amide bonds with free amines have been applied [88], or alternatively p-isothiocyanato-DFO forming a stable thiourea bond with lysine residues [89]. Standardized protocols have been established [90] making 89 Zr labelling for Immuno-PET applications ever more widely applicable. Several reviews have summarized the latest progress of 89 Zr-DFO-conjugated antibodies [82][83][84].…”

EATRIS, a Vision for Translational Research in Europe

“…It provides substantial added value in several ways. Molecular imaging and its concomitant area of tracer development is becoming an essential tool for understanding disease mechanisms by visualising and allowing quantification of critical disease targets and molecules, be it drug candidates or diagnostic agents [6,7]. The use of molecular imaging in evaluating the efficacy of new drugs, testing early in the process (phase I/II) with small imagingenabled trials, allows the elimination of dead-end compounds before vast multi-centre trial expenditures are made.…”