The Regulation of Platelet Aggregation In Vitro by Interleukin-1 β and Tumor Necrosis Factor-α: Changes in Pregnancy and in Pre-eclampsia

Abstract

SummaryPlatelet activation occurs in early pregnancy in women at risk of developing pre-eclampsia. Cytokines have been implicated in the pathogenesis of pre-eclampsia, so we determined the effects of interleukin- 1β (IL-1β) and tumor necrosis factor-α (TNF-α) on the in vitro aggregation of human platelets. IL-1β increased aggregation of platelets from non-pregnant and pre-eclamptic women, and inhibited the aggregation of platelets from normal pregnant women. This latter effect was linked to a diminished P-selectin expression on ADP-stimulated whole blood platelets in normal pregnant women (p = 0.011). Platelet aggregation in response to ADP was found to be inhibited after preincubation with TNF-α in non-pregnant (38%, p = 0.01) and in normal pregnant women (54%, p = 0.001) and not affected in pre-eclamptic women. The inhibitory effects of TNF-α were mediated through the P75 receptor for TNF-α.