title: Detection of myeloperoxidase by flow cytometry in acute leukemia.
abstract: The value of flow cytometric detection of myeloperoxidase (MPO) in the differential diagnosis of acute leukemia was evaluated in 57 cases of acute leukemia and in 9 leukemia cell lines. Cells were fixed and permeabilized with Fix & Perm cell permeabilization kit at room temperature for 15 min each, and stained with anti-MPO monoclonal antibody (MPO-7) by direct immunofluorescence. One myeloid cell line, HL-60, was MPO-positive, while the other myeloid cell lines (KG-1, K-562, and MEG-01) as well as lymphoid cell lines (KM-3, NALM-6, Raji, REH, and T-ALL-1) were MPO-negative as previously described. Among acute leukemias, MPO was detected in 23 of 26 cases of acute myeloid leukemia (AML), 7 of 23 cases of B-lineage acute lymphoblastic leukemia (ALL), 1 of 6 cases of T-lineage ALL (T-ALL), and 1 of 2 cases of acute unclassified leukemia (AUL). The intensity of MPO expression in 6 of 7 B-lineage ALL cases was weak compared with AML labeling. There was no detectable cytochemical MPO in the cells of ALL, AUL, or AML that stained negative for anti-MPO. No relationship between the expression of MPO and myeloid lineage surface antigens was observed in ALL. Three cases of MPO-positive ALL and AUL could be reclassified as biphenotypic leukemia according to the revised Catovsky scoring system. These results indicate that anti-MPO is an excellent marker for the diagnosis and classification of acute leukemia and can be reliably detected by flow cytometry. This rapid technique should be a valuable addition to routine immunophenotyping of acute leukemia.
authors.affiliation: Department of Haematology, Westmead Hospital, New South Wales, Australia.
authors.forename: K
authors.initials: K
authors.lastname: Nakase
authors.forename: M
authors.initials: M
authors.lastname: Sartor
authors.lastname: Bradstock
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000032:analysis; D015214:Antigens, Differentiation, Myelomonocytic / Q000032:analysis; D002051:Burkitt Lymphoma / Q000201:enzymology* / Q000276:immunology; D018826:CD13 Antigens / Q000032:analysis; D002648:Child; D005434:Flow Cytometry / Q000379:methods*; D018922:HL-60 Cells; D006801:Humans; D007951:Leukemia, Myeloid / Q000201:enzymology* / Q000276:immunology; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000201:enzymology* / Q000276:immunology; D009195:Peroxidase / Q000378:metabolism*; D063268:Sialic Acid Binding Ig-like Lectin 3; D014407:Tumor Cells, Cultured
chemical_list: D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; C571163:CD33 protein, human; D063268:Sialic Acid Binding Ig-like Lectin 3; D009195:Peroxidase; D018826:CD13 Antigens