Immunoscintigraphy of atherosclerotic uncomplicated lesions in vivo with amonoclonal antibody against D-dimers of insoluble fibrin

To test the effectiveness of a new F(ab')(2) monoclonal antibody against hu man fragment D-dimer of cross-linked fibrin in the detection of uncomplicat ed atherosclerotic lesions of the carotid Vessel previously documented at e cho-color-Doppler and selective arteriographic study, 8 patients underwent a scintigraphic study including dynamic and early and delayed (3 h later) s tatic imaging of the neck after injection of a bolus of Tc-99m-labeled mono clonal antibody, and were subsequently operated. Vessel specimens and blood samples were drawn at operation and counted. No adverse reaction occurred after administration of the monoclonal antibody. The atherosclerotic lesion appeared as a focal area of asymmetrical tracer uptake, already visible at early images in four patients, and at delayed images in five. The average tracer uptake ratio between pathological and normal vessels was 1.40 +/- 0. 24 (P < 0.05) at time-activity curves derived from dynamic images, 2.17 +/- 0.97 (P < 0.05) at early static images and 2.05 +/- 0.98 (P < 0.05) at del ayed static images, respectively. Mean vessel to blood uptake rate of speci mens obtained at operation was 2.22 +/- 0.59 (P < 0.001). The study shows t hat the Tc-99m-labeled antibody was found to be safe and capable of detecti ng atherosclerotic plaques in humans. (C) 1999 Elsevier Science Ireland Ltd . All rights reserved.