title: Inhibition of interleukin-1 activity by equine synovial fluid.
abstract: 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.
authors.affiliation: Department of Veterinary Basic Sciences, Royal Veterinary College, Hatfied, Herts, UK.
authors.forename: S A
authors.initials: SA
authors.lastname: May
authors.forename: R E
authors.initials: RE
authors.lastname: Hooke
authors.forename: P
authors.initials: P
authors.lastname: Lees
mesh_terms: 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*
chemical_list: D007375:Interleukin-1; D015232:Dinoprostone