Simultaneous determination of percentage of Lens culinaris agglutinin-reactive alpha-fetoprotein and alpha-fetoprotein concentration using the LiBASys clinical auto-analyzer.

BACKGROUND

Lens culinaris agglutinin (LCA)-reactive alpha-fetoprotein (AFP-L3) percentage of total AFP concentration [(AFP-L3/total AFP)x100] has been used as an effective marker for earlier diagnosis, for assessment of therapeutic effects and for predicting the prognosis of hepatocellular carcinoma (HCC).

METHODS

A new clinical automatic analyzer, the "LiBASys", and an assay kit for the simultaneous determination of AFP-L3 percentage and concentration of AFP in human serum were developed. LiBASys performed automatic re-measurement and also met stat samples. Both AFP-L3 percentage and AFP concentration were calculated simultaneously and printed out continuously every 3.4 min per test.

RESULTS

A linear dose-response relationship was observed up to 1000 ng/ml AFP concentration. The detection limit and functional sensitivity of LCA-nonreactive AFP (AFP-L1) and AFP-L3 concentrations were 0.4 and 0.8 ng/ml, and 0.4 and 1.0 ng/ml, respectively. Interassay CVs of AFP-L3 percentage and AFP concentration ranged from 2.8% to 13.4% and 2.6% to 4.6%, respectively. Assay results exhibited good correlations with those of commercially available lectin-affinity electrophoresis (r=0.984) for AFP-L3 percentage and with the RIA method (r=0.999) for AFP concentration.

CONCLUSIONS

This method simultaneously yields both qualitative and quantitative results for AFP-L3 percentage and AFP concentration.