A simultaneous flow cytometric measurement of neutrophil phagocytosis and oxidative burst in whole blood.

To quantitate phagocytosis and respiratory burst by polymorphonuclear leukocytes (PMNs), 1-ml aliquots of human whole blood were incubated with 50 microM dichlorofluorescin diacetate for 10 min at 37 degrees C prior to the addition of Texas Red-labelled Staphylococcus aureus (SA). At 5-min intervals PMNs were analyzed by flow cytometry for ingested SA and resultant production of hydrogen peroxide, an oxidative burst metabolite. PMNs from infected patients or normals that had been primed for 1 hr with bacterial endotoxin displayed enhanced phagocytosis and oxidative burst activity compared to controls. PMNs from a patient with chronic granulomatous disease were less reactive than those of normals. The whole blood analysis is a simple, rapid, and inexpensive technique for the clinical evaluation of PMN function in a physiologic milieu.