Determination of ectoenzyme activities in leukemic cells and in established hematopoietic cell lines

Abstract

Ectoenzyme activities were determined in peripheral blood cells from patients with acute leukemias, from normal controls, and in cells of hematopoietic cell lines. In common acute lymphoblastic leukemia, cell membrane-associated 5'-nucleotidase (5'-N) activity was significantly higher than in acute T and unclassified lymphoblastic leukemias. In acute myeloblastic and myelomonocytic leukemias, cells contained significantly higher gamma-glutamyl transpeptidase (gamma-GT) activity than in lymphoblastic leukemias. Normal B lymphocytes differed from T cells and monocytes mainly in their 5'-N activity, whereas in monocytes, gamma-GT activity was more pronounced than in other normal blood cells. Hematopoietic cell lines showed some distinct patterns of ectoenzyme activity. Most B cell lines had high 5'-N and (Na-K-Mg) adenosine triphosphatase activities. In lines of myeloid origin, elevated gamma-GT values were found. In lymphoid stem cells and in T lymphoblast lines, most ectoenzyme activities were lower than in the other cell lines. In some cell lines, characteristic high-activity marker enzymes were detected.

Contribution by Polymorphonucleate Granulocytes to Elevated Gamma-Glutamyltransferase in Cystic Fibrosis Sputum

“…Nevertheless other non-epithelial sources should be taken into account when considering the GGT increase in CF lungs. In particular, some studies demonstrated the expression of GGT in human lymphoid cells and an increase of GGT activity was described in the granulocytic cell lineage along with cell maturation [17], during differentiation of lymphocytes [18] and monocytes/macrophages [19]. In neutrophils GGT is localized in microsomal and granular fractions and released upon neutrophils activation with calcium-ionophore A23187 [9], [17], [20].…”

Apoptosis in human lymphoblastoid cells induced by acivicin, a specific γ glutamyltransferase inhibitor

“…y-GT activity is useful for discriminating between the y-GT-positive blasts of non-lymphoid origin and y-GTnegative lymphoid blasts in acute undifferentiated leukemias (Heumann et al, 1985). In a culture system of neoplastic T-cell lines with a progressive level of phenotypic differentiation but similar % S-phase, CEM cells were found to have a very high level of y-GT activity, 10-fold more than that of HSB-2, Jurkat and MOLT-4 T-lymphoblastoid cell lines (Morell et al, 1986;.…”

“…But there is almost no y-GT activity in some hematopoietic neoplasms, such as acute lymphoblastic leukemias of the common (CALL) and thymic (T-ALL) phenotype (Heumann et af, 1985). In contrast, this enzyme is expressed in acute myeloid leukemias (Ml-M3), and is at a very high level in acute myelomonocitic (M4) and monocitic leukemias (M5) and in the blast crisis of chronic myeloid leukemia (CML-BC) (Morell et al, 1986;Losa et al, 1993). y-GT activity is useful for discriminating between the y-GT-positive blasts of non-lymphoid origin and y-GTnegative lymphoid blasts in acute undifferentiated leukemias (Heumann et al, 1985).…”