Flow cytometric determination of active oxygen (hydroperoxide) produced by peripheral blood neutrophils in patients with hematological disorders.

We analyzed active oxygen (hydroperoxide; H2O2) production by peripheral neutrophils in various hematological diseases by flow cytometry. One hundred microliters of heparinized fresh blood was sequentially incubated at 37 degrees C with 2',7'-dichlorofluorescein diacetate and with or without phorbol myristate acetate (PMA). After hemolysis, the pelleted white blood cells were subjected to flow cytometry, and the neutrophil fraction was gated on the cytogram. Production of H2O2 by the fraction was estimated by determining the increase in the relative intensity of fluorescence emitted from the fraction in response to stimulation by PMA. In controlled chronic myelogenous leukemia (CML) (WBC < 1 x 10(10)/1), H2O2 production was normal, while in uncontrolled CML (WBC > or = 1 x 10(10)/1), it was reduced. In myelodysplastic syndrome (MDS), H2O2 production was also reduced, but no significant difference was observed among FAB classification disease types in MDS patients. In untreated acute non-lymphocytic leukemia (ANLL), H2O2 production was reduced, while in the complete remission stage of ANLL, its level was normal, suggesting recovery from normal clones. In aplastic anemia, the H2O2 production level was normal. Steroid therapy might be responsible for the reduction of H2O2 production in non-Hodgkin's lymphoma and multiple myeloma. The production of H2O2 is closely related to the oxygen-dependent bactericidal activity of neutrophils, and, hence, can be utilized as an index to indicate susceptibility to infection. This neutrophil function can be determined easily in ordinary clinical facilities by using flow cytometry, and care should be taken to prevent infection when H2O2 production is reduced.(ABSTRACT TRUNCATED AT 250 WORDS)