The Specificity and Accuracy of (111)In-Hexavalent Lactoside in Estimating Liver Reserve and Its Threshold Value for Mortality in Mice.

BACKGROUND & AIMS:The asialoglycoprotein receptor on hepatocyte membranes recognizes the galactose residues of glycoproteins. We investigated the specificity, accuracy and threshold value of asialoglycoprotein receptor imaging for estimating liver reserve via scintigraphy using (111)In-hexavalent lactoside in mouse models.METHODS:(111)In-hexavalent lactoside scintigraphy for asialoglycoprotein receptor imaging was performed on groups of normal mice, orthotopic SK-HEP-1-bearing mice, subcutaneous HepG2-bearing mice, mice with 20-80% partial hepatectomy and mice with acute hepatitis induced by acetaminophen. Liver reserve was measured by relative liver uptake and compared with normal mice. Asialoglycoprotein receptor blockade was performed via an in vivo asialofetuin competitive binding assay.RESULTS:A total of 73.64±7.11% of the injection dose accumulated in the normal liver tissue region, and radioactivity was barely detected in the hepatoma region. When asialoglycoprotein receptor was blocked using asialofetuin, less than 0.41±0.04% of the injection dose was detected as background in the liver. Asialoglycoprotein receptor imaging data revealed a linear correlation between (111)In-hexavalent lactoside binding and residual liver mass (R(2)=0.8548) in 20-80% of partially hepatectomized mice, demonstrating the accuracy of (111)In-hexavalent lactoside imaging for measuring the functional liver mass. Asialoglycoprotein receptor imaging data in mice with liver failure induced using 600mg/kg acetaminophen revealed 19-45% liver reserve relative to normal mice and a fatal threshold value of 25% liver reserve.CONCLUSION:The (111)In-hexavalent lactoside imaging method appears to be a good, specific, visual and quantitative predictor of functional liver reserve. The diagnostic threshold for survival was at 25% liver reserve in mice.