RADIOLABELED MONOCLONAL-ANTIBODIES (MCAB) - AN ALTERNATE APPROACH TO THE CONVENTIONAL METHODS FOR THE ASSESSMENT OF CARDIOMYOCYTE DAMAGE INAN EXPERIMENTAL BRAIN-DEATH PIG MODEL

The present study was carried out to determine the possible use of cTn -l in the cardiac myofibrillar architecture, as a potential target for in vivo radioimmunodetection of cardiac damage in a brain death pig m odel. Radioiodiantion of the anti-cTn-l 5F4 McAb was carried out by la ctoperoxidase method. The percentage iodine incorporation achieved was 70 similar to 75%. The radioiodinated McAbs were purified on Sephadex G-25 column and characterised by Paper chromatography, Phast Cel elec trophoresis and electroimmunoblotting. Radioiodinated anti-cTn-l 5F4 M cAbs were employed alongside Pyrophosphate (Tc-99m-PPi) and Thallium(2 01) chloride (Tl-201) in 24 landrace pigs (brain-dead=18 & sham-operat ed=6). The percentage cardiac uptake of the radiolabelled antibody inj ected dose was significantly higher in the brain dead animals (0.196%) as compared to that of sham-operated animals (0.11%). Specific in viv o localization of radiolabelled McAbs in the infarcted cardiac tissue was confirmed by computer-aided reconstruction of 3-D images of the is olated heart. The preliminary results of the study revealed preferenti al uptake of radiolabelled antibody at the site of myocyte damage resu lting from artificially induced brain death.