Locomotion of Human Neutrophils in Response to Plasma and Serum of Women with Preeclampsia

Neutrophil oxygen radical production in pre-eclampsia with HELLP syndrome

OBJECTIVE

To determine whether severe pre-eclampsia complicated by hemolysis, elevated liver enzymes, low platelets (HELLP) syndrome alters neutrophil oxygen radical production.

MATERIALS AND METHODS

Neutrophils were obtained from 10 healthy non-pregnant, 9 normal pregnant and 9 women with severe pre-eclampsia with concurrently HELLP syndrome. Oxygen radical production was evaluated using luminol-enhanced chemiluminescence and measured by cytochrome C reduction. Furthermore we incubated sera from cases and controls with isolated healthy neutrophils and measured their capacity to generate oxygen radicals.

RESULTS

Unstimulated neutrophil oxygen radical production was significantly lower in severe pre-eclamptics compared with healthy non-pregnant and pregnant subjects, whereas phorbol ester-induced oxygen radical production did not differ among categories. Cytochrome C reduction of unstimulated neutrophils showed similar results. Healthy neutrophils incubated with sera from pre-eclamptics enhanced the oxygen radical production significantly more than neutrophils incubated with sera from the healthy subjects.

CONCLUSIONS

Severe pre-eclampsia is characterised by decreased unstimulated neutrophil oxygen radical production. This may be the result of an exhausted cellular response due to stimulation by a factor present in the serum of these patients.

The role of the endogenous anti-inflammatory compound gravidin in pre-eclampsia

OBJECTIVES

The study's aims were to investigate the levels of gravidin, an endogenous phospholipase A2 inhibitor, in pregnancy and pre-eclampsia and to establish its effects on neutrophil function.

STUDY DESIGN

Serum samples were collected from 9 nonpregnant, 15 preeclamptic, and 10 healthy pregnant women and assayed for free gravidin by enzyme-linked immunosorbent assay. Neutrophil phospholipase A2 and respiratory burst activities were determined in the presence of isolated free gravidin by cellular arachidonic acid release and superoxide anion production.

RESULTS

Levels of free gravidin were higher in the healthy pregnant (36.1 +/- 5.5 ng/mL) and preeclamptic (17.8 +/- 2.8 ng/mL) groups than in the nonpregnant control group (3.9 +/- 0.5 ng/mL) and were significantly different between pregnancy groups (P <.01, Mann-Whitney U test). Free gravidin caused a concentration dependent decrease in N-formyl-methionyl-leucyl-phenylalanine-stimulated neutrophil arachidonic acid release (inhibitory concentration of 50% 25 nmol/L) and superoxide anion generation (inhibitory concentration of 50% 32 nmol/L).

CONCLUSIONS

Circulating levels of free gravidin are reduced in pre-eclampsia compared with normal pregnancy. This may encourage an increase in the respiratory burst of neutrophils in pre-eclampsia and could contribute to the oxidative stress and vascular damage that characterize this disease.