Inhibition of interleukin-1 activity by equine synovial fluid.
The presence, in equine synovial fluid, of inhibitors of interleukin-1 (IL-1) activity has been investigated by means of an assay involving IL-1-mediated production of PGE2 by synovial cells. Inhibitors of IL-1 alpha and IL-1 beta were identified in normal synovial fluid and synovial fluid from two horses with early joint disease. Inhibitors of IL-1 alpha were also present in synovial fluid from two horses with long-standing joint disease. However, IL-1 beta inhibitory activity was not present in fluid from the horses with more chronic joint disease. The effect appeared to be specific for IL-1, and not a direct action on PGE2 production, as synovial fluid had no effect on lipopolysaccharide-mediated PGE2 production. It is suggested that the inhibitory activity may be involved physiologically in the control of IL-1 activity in the joint, and the loss of IL-1 inhibition may be at least as important biologically as increased production of IL-1.
May
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Department of Veterinary Basic Sciences, Royal Veterinary College, Hatfied, Herts, UK.
Hooke
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Lees
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D000818:Animals; D002908:Chronic Disease; D015232:Dinoprostone / Q000037:antagonists & inhibitors / Q000096:biosynthesis; D006734:Horse Diseases / Q000276:immunology*; D006736:Horses; D007375:Interleukin-1 / Q000037:antagonists & inhibitors*; D007592:Joint Diseases / Q000276:immunology / Q000662:veterinary*; D013582:Synovial Fluid / Q000276:immunology*
D007375:Interleukin-1; D015232:Dinoprostone