Functional Characteristics of Human Toxic Neutrophils

The function of toxic neutrophils from patients with severe infection and inflam-mation was studied by in-vitro determination of their chemotactic, migratory, phagocytic, and bactericidal activities. Toxic neutrophils had 21 % of the chemo-tactic activity of controls. Staphylococcus albus was destroyed less readily by toxic neutrophils, but the differences observed between toxic and control neutrophils were small. After incubation for 2 hr, toxic neutrophils killed 81 % of the original inoculum, while control cells killed 97 %. This small reduction in total bacterial clearance by toxic neutrophils was associated with increases in both free and cell-associated bacteria, suggesting a compromise in phagocytic and bactericidal activities. Sera from patients with toxic neutrophils did not affect normal neutro-phils. Studies of phagocytes from ten patients who had febrile illnesses without toxic neutrophils were normal. None of these patients had severe bacterial infection. No alterations in function were detected in neutrophils of two patients with polycythemia vera and one with myeloid metaplasia. Severe bacterial infections sometimes follow an inexorable course which leads to the death of the host despite treatment with appropriate antibi-otics [1]. During such infections and other severe inflammatory processes, morphologic changes frequently occur in human peripheral blood neu-trophils visualized by Wright's stain [2]. The best known alteration is the shift to the left, based on nuclear configuration, and defined by the pres-ence of band forms of neutrophils, metamyelo-cytes, and sometimes myelocytes. The cytoplas-mic changes which may accompany the shift to the left in individual neutrophils have been em-phasized less frequently. They include: (1) the presence of granules which stain more promi-nently than those of normal neutrophils (toxic Received for publication December 10, 1970, and in revised form March 10, 1971. This study was supported by grant AI09169 from the