Elevation of serum asialo-α₁ acid glycoprotein concentration in patients with hepatic cirrhosis and hepatocellular carcinoma as measured by antibody-lectin sandwich assay

Serum asialoglycoproteins (desialylated glycoproteins) concentration was reported to be elevated in patients with hepatic disease as compared with that of normal subjects. In this study, we measured serum asialo-α₁ acid glycoprotein (AsAGP) level by a solid-phase sandwich assay in which monoclonal antibody (mAb) to α₁-acid glycoprotein and galactose-binding lectin, ricinus communis (RCA), have been employed as capture protein and probe protein, respectively. The mAb-RCA sandwich assay was sensitive (0.02 μg/ml) and specific for AsAGP. We have determined AsAGP concentration of 869 serum specimens and analyzed the results using 1.38 and 2.24 μg/ml (AsAGP) as cut-off values, respectively. AsAGP level was 0.80 ± 0.29 μg/ml (mean ± S.D.) with 97 normal serum specimens and elevated primarily in patients with liver cirrhosis (LC) or hepatocellular carcinoma (HCC). Using 1.38 μg/ml as a cutoff, 4/97 normal subjects, 11/39 acute hepatitis and 26/159 non-hepatic disease exhibited a slight elevation, whereas, AsAGP level was significantly elevated in 182/230 LC and 63/72 HCC. Meanwhile, a cutoff of 2.24 μg/ml allowed significant differentiation of LC or HCC from chronic hepatitis. Serum AsAGP level appeared to increase progressively with increasing severity of liver disease in cirrhotic patients. Thus, serum AsAGP concentration, as measured by the new mAb-RCA sandwich assay, may be a useful differential marker as a diagnostic aid for LC or HCC.