Potential application of labeled antibodies for thrombus detection

Area of Science:

• Biomedical Imaging
• Hematology
• Immunology

Background:

• The established 111In-oxine method for platelet labeling and thrombus imaging is cumbersome.
• Monoclonal antibodies offer a potential alternative for more accessible platelet labeling.

Purpose of the Study:

• To evaluate the efficacy of monoclonal antibody 7E3 labeled with 131I and 111In for imaging experimental thrombi in dogs.
• To compare this novel method with the conventional 111In-oxine technique.

Main Methods:

• Canine platelets were labeled with 7E3, a monoclonal antibody targeting glycoprotein IIb/IIIa, using 131I and 111In-DTPA conjugate.
• Experimental deep vein and coronary thrombi were induced in dogs.
• Whole blood was incubated with labeled 7E3, and thrombi were subsequently identified ex vivo.

Main Results:

• 131I- and 111In-labeled 7E3 successfully identified experimental deep vein thrombi in all tested dogs (4/4).
• Coronary thrombi were identified in 1/3 dogs at 4 hours with clot-to-blood ratios of 7-13:1.
• The 111In-oxine method failed to detect any coronary thrombi (0/3).

Conclusions:

• 131I- and 111In-labeled 7E3 provide a readily applicable method for identifying peripheral venous thrombi.
• Further optimization for faster clearance of labeled platelets is necessary for reliable coronary thrombus detection.