Distinct alpha-L-fucosidase isoenzyme profiles in human leukemic cells

alpha-L-Fucosidase (EC 3.2.1.51; FUS) activity and isoenzyme characteristics were analyzed in normal lymphocytes, normal granulocytes (PMNs) and myeloid and lymphoid leukemic cells, (AML, AMMoL, ALL, CLL and CML). CLL lymphocytes had a lower mean specific activity than normal lymphocytes (2.5 v 4.0, p less than 0.05). ALL blasts had a higher mean specific activity compared to normal lymphocytes (9.7 v 4.0; p less than 0.001), CLL lymphocytes (9.7 v 2.5; p less than 0.001) and AML blasts (9.7 v 7.6 p = NS). Normal PMNs had a higher mean specific activity than normal lymphocytes (7.0 v 4.0 p less than 0.05) but similar activity when compared to CML cells or AML blasts. Blasts from AMMoL patients had higher activity than normal PMNs (9.0 v 7.0; p less than 0.05). The isoenzyme patterns of normal and leukemic granulocytes and lymphocytes were obtained by automated chromatofocusing on PBE-94 microcolumns with normal and leukemic lymphocyte lysates. With normal and leukemic lymphoid lysates two major isoenzyme components (B and A) were isolated. The isoenzyme pattern of PMN, AML, CML and AMMoL revealed 3 major peaks (B, A, I), totally different from that seen in lymphoid cells. The patterns of AML, CML and PMN appeared to be similar to each other; however, the isoenzyme pattern obtained from AMMoL cells could be distinguished from the others by a prominent I peak. Thus the FUS isoenzyme profile distinguishes the blasts of AMMoL from AML, and AMMoL and AML from ALL.