SPONTANEOUS NITROBLUE-TETRAZOLIUM (NBT) REDUCTION RELATED TO GRANULOCYTE PRIMING AND ACTIVATION

The aim of the present study was to explore the relationship between t he increasing level of spontaneous NET-reduction and the tendency for PMNs to marginate during experimental hemorrhagic shock in rats. Rat P MNs, isolated on Percoll(R) density gradients or suspended in blood, w ere examined by chemiluminescence (CL), NET-test and by their CD-18 ex pression and F-actin formation. The NET-test generally produced higher numbers of activated PMNs when the cells were suspended in buffer tha n in whole blood, probably due to the scavenging properties of blood. The level of spontaneous NET-reduction of PMNs in blood correlated wit h the magnitude of the NET-response to f-MLP stimulation in blood and buffer. On the contrary, there were no significant correlations betwee n spontaneous NET reduction, CD18 expression and F-actin content. Thus , high levels of spontaneous NET reduction in blood were associated wi th priming of the separated PMNs rather than increased rigidity (F-act in) or adhesiveness (CD18).