NEUTROPHIL CD11B EXPRESSION AND NEUTROPHIL ACTIVATION IN PREECLAMPSIA

1. Neutrophil activation was examined in 22 women with pre-eclampsia a nd 22 age- and gestation-matched control subjects using whole-blood fl ow cytometry to assess basal and platelet-activating factor stimulated CD11b and CD18. 2. Basal neutrophil CD11b expression was significantl y increased in women with pre-eclampsia compared with normal pregnancy before delivery, A similar non-significant trend for CD18 was also ob served. 3. Before delivery, neutrophil CD11b expression increased in a dose-dependent fashion after platelet-activating factor stimulation, with the differences between the groups maintained, A similar dose-dep endent increase in CD18 expression was observed after platelet-activat ing factor. 4. There were no between-group differences in expression o f either CD11b or CD18 at either 6 weeks or 6 months post partum, eith er before or after platelet-activating factor stimulation. 5. Neutroph il CD11b was positively correlated with plasma uric acid (r = 0.44, P = 0.04) in women with pre-eclampsia, suggesting that the extent of neu trophil activation correlates with disease severity. 6. An increase in basal neutrophil CD11b expression in women with pre-eclampsia is like ly to be an index of neutrophil activation in vivo, Neutrophil release of free radicals and proteases may then help perpetuate a vicious cyc le of endothelial and vascular dysfunction in the placental and system ic circulations. The cause of this activation is not known but could i nvolve platelet activation, increased production of endothelin-l or re lease of cytokines, Further studies will be required to elucidate the consequences of neutrophil activation in pre-eclampsia.