Summary
Immune triggered granulocyte (PMN)-endothelial interactions have been implicated in
the pathogenesis of vascular diseases. While hyperuricemia and gout are associated
with an increased risk of atherogenesis, we studied the modulation by mono- sodiumurate
(MSU) crystals of PMN-endothelial interactions in vitro. The relationship between
calciumoxalate (COX) crystals - implicated in the vasculitis of primary oxalosis -
and immunologically mediated endothelial injury was also explored.
Both MSU- and COX-crystals activate complement (C), as illustrated by the finding
of strong PMN aggregating activity and large amounts of C3a and C5a-anaphylatoxin in MSU- and COX- crystal incubated sera.
MSU- and COX-crystal treated sera stimulate PMN to adhere to and induce significant
51Cr-release from endothelial cells in vitro. Platelets significantly increase crystal-triggered
PMN endothelial cell adherence and 51Cr-release. This platelet augmenting effect depends on the release of platelet constituents
(e. g. serotonin).
Microcrystalline material present in vessel walls, thus may cause C-activation and
may trigger PMN and platelets to damage endothelium in vitro and in vivo. These findings
may have relevance to the understanding of the accelerated atherogenesis of hyperuricemia
and the fulminant vasculitis of oxalosis or ethylene glycol poisoning.
Keywords
Hyperuricemia - Gout - Oxalosis - Endothelium - Granulocytes - Immune damage - Complement
