ABSTRACT
Objective To establish a time resolved fluoroimmunoassay (TRFIA) method for detecting Glypican 3 (GPC3) and to explore the diagnostic value of serum GPC3 for hepatic carcinoma (HCC). Methods Microplate coated with anti-GPC3 monoclonal antibody 7C8 and GP9 labeled with Eu3+ were used to establish TRFIA kit. The serum concentrations of GPC3 in 41 HCC patients and 44 chronic hepatitis (CH) patients were quantitatively analyzed. AFP was detected by with lowest limit of 2.06 μg/L. The CV of inter and intra assay were 12.25% and 12.91%, respectively. The average serum concentration of GPC3 in HCC patients was (86.68±110.39) μg/L (median: 56.98 μg/L). But in CH patients it was only (14.77±29.48) μg/L, which was significantly lower than that in HCC (Wilcoxon W=1335.00, Z=-4.99, P<0.001). With diagnostic cut-off value set at 42.94 μg/L, the diagnostic sensitivity and specificity of TRFIA GPC3 for HCC were 58.5% (24/41) and 95.5%(42/44) respectively. The diagnostic sensitivity of AFP was 46.3% (19/41) in 41 HCC patients, and was raised to 78.0% (32/41) when combined with GPC3. Conclusions Serum GPC3 assay by TRFIA is established and it could increase the diagnostic sensitivity for HCC when combined with AFP.