LOCOMOTION OF HUMAN NEUTROPHILS IN RESPONSE TO PLASMA AND SERUM OF WOMEN WITH PREECLAMPSIA

Objective: To examine whether the previously reported neutrophil activ ation which occurs in the maternal circulation of women with preeclamp sia is due to a factor(s) in plasma/serum which increases neutrophil l ocomotion. Methods: The locomotory responses of human neutrophils to p lasma/serum of women with preeclampsia were compared with normal, preg nant women matched for maternal age and gestational age at blood sampl ing. Twelve patients from each group were studied. Preeclampsia was de fined as persistent diastolic blood pressure > 90 mm Hg, with proteinu ria > 0.3 g/24 h, in patients who were normotensive before 20 weeks ge station. A simple microcomputer-based system for real-time analysis of neutrophil behavior in vitro was used to measure the dynamic paramete rs of locomotion. Locomotion of human neutrophils in response to plasm a, serum (20%), and heat-inactivated serum from both groups of patient s was measured. Serum was heat inactivated to destroy complement-deriv ed chemotactic activity. Main Outcome Measures: Speed, persistence, an d diffusion coefficient to describe the behavior of randomly moving ce lls. Results: A significant stimulation of neutrophil locomotion in re sponse to plasma, serum (20%), and heat-inactivated serum occurred in both groups compared with control cells incubated with phosphate-buffe red saline; however, no significant differences were found in response ;to these three stimuli between the two groups of patients. Conclusion : These studies found no evidence of a humoral factor in the plasma/se rum of women with preeclampsia which alters the locomotion of human ne utrophils. The existence of such a potential factor may be revealed, h owever, upon examination of subsequent stages of neutrophil activation , namely adhesion to endothelial cells and/or neutrophil metabolic act ivation.