Electrofocusing patterns of fucosyltransferase activity in plasma of patients with chronic granulocytic leukemia

Fucosyltransferase activity was measured in plasma samples obtained from patients with chronic granulocytic leukemia in different disease stages. Total enzyme activity was generally elevated in untreated and in stable disease; a marked further elevation was noted 30 to 60 days before development of blast crisis. Electrofocusing studies indicate the presence of three major enzymes. The level of enzyme which focused at pH 5.6 was elevated in untreated disease and rose markedly during blastic transformation. A second enzyme focused at pH 5.1 and appeared to be related to marrow erythroid turnover. A third enzyme with pI = 4.7 was elevated only during marrow regeneration which followed myelosuppressive therapy. These data suggest the enzyme with pI = 5.6 to be a specific marker in chronic granulocytic leukemia.