title: Development of des-gamma-carboxy prothrombin (DCP) measuring reagent using the LiBASys clinical analyzer.
abstract: 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.
authors.affiliation: New Diagnostics Business and Technology Development Department, Wako Pure Chemical Industries Ltd., Hyogo, Japan. yamaguchi.isao@wako-chem.co.jp
authors.forename: Isao
authors.initials: I
authors.lastname: Yamaguchi
authors.forename: Kenji
authors.initials: K
authors.lastname: Nakamura
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Kitano
authors.forename: Yoshie
authors.initials: Y
authors.lastname: Masuda
authors.forename: Futoshi
authors.initials: F
authors.lastname: Kanke
authors.forename: Shinzo
authors.initials: S
authors.lastname: Kobatake
authors.forename: Shinji
authors.initials: S
authors.lastname: Satomura
mesh_terms: D015415:Biomarkers / Q000097:blood* / Q000737:chemistry*; D006528:Carcinoma, Hepatocellular / Q000097:blood; D019963:Clinical Chemistry Tests / Q000295:instrumentation / Q000379:methods*; D007202:Indicators and Reagents; D016014:Linear Models; D011498:Protein Precursors / Q000097:blood* / Q000737:chemistry*; D011516:Prothrombin / Q000737:chemistry*; D012680:Sensitivity and Specificity; D000509:alpha-Fetoproteins / Q000032:analysis
chemical_list: D015415:Biomarkers; D007202:Indicators and Reagents; D011498:Protein Precursors; D000509:alpha-Fetoproteins; C008208:acarboxyprothrombin; D011516:Prothrombin