Background: Des-gamma-carboxy prothrombin (DCP), Lens culinaris agglutinin-reactive alpha-fetoprotein ratio (AFP-L3) and total alpha-fetoprotein (AFP) are tumor markers useful for diagnosing and determining the prognosis of hepatocellular carcinoma (HCC). There is a real need for measurement of these three markers on a one-assay platform.
Methods: A method of DCP measurement in human serum was developed using liquid binding assay (LBA), which enables rapid antigen-antibody reaction and bound/free separation on the LiBASys clinical analyzer.
Results: The dilution curve for DCP was linear up to 500 ng/mL. The limit of detection of DCP concentration was 0.5 ng/mL. Intra- and inter-assay coefficients of variation of DCP were 0.7%-2.4% and 2.2%-6.5%, respectively. This method was free from interference by hemoglobin, bilirubin, ditaurobilirubin, intrafat, ascorbate, galactose, glucose and rheumatoid factor. The analytical recoveries of DCP added to serum were 91.7%-108.2%. DCP concentration measured with the LBA method was linear and was significantly correlated with that measured with the ELISA method.
Conclusions: The LiBASys clinical analyzer made possible measurement of the complementary tumor markers, HCC, total AFP, AFP-L3 and DCP.