Specific precipitation assay of bone and liver isoenzymes of serum alkaline phosphatase

: Wheat Germ Agglutinin (WGA) precipitates bone and biliary isoenzymes of serum alkaline phosphatase, when liver and intestinal isoenzymes remain in the supernatant. Biliary and intestinal isoenzymes--when present--are evaluated with electrophoresis. Isoenzymes content in precipitate and supernatant is studied by electrophoresis and heat-inactivation. The results of WGA technique are compared to those obtained with heat-inactivation. Heat inactivation reproducibility is poor when compared to WGA precipitation. Differences are found when data of 61 sera are studied. Since a reference method is lacking, results are correlated with other biological parameters, specific of hepato-biliary pathology, and with clinical data, such as metastasis localisation. This study shows that lectin precipitation yields more accurate results than heat-inactivation.