title: Cytokines in synovial fluid. I. The presence of biologically active and immunoreactive IL-1.
abstract: Using a sensitive IL-1-dependent T cell clone we estimated interleukin 1 (IL-1)-like activity in a variety of synovial fluids (SF). Although we demonstrate that SF contains potent inhibitors of endogenous and exogenous IL-1 we were able to estimate that samples from rheumatoid arthritis, osteoarthritis and other arthritides contain the equivalent of tens or hundreds of picograms of IL-1 per millilitre, when compared to a standard IL-1 preparation. Although there was some correlation between these results and those obtained using a radio-immunoassay (RIA) for IL-1 beta, the RIA indicated that IL-1 was present in the nanogram range. The results suggest that the importance of inhibitors of IL-1 in SF merits particular attention and that it is also important to consider the bioactivity of cytokines which may be detected by physical methods.
authors.affiliation: University of Manchester, Rheumatic Diseases Centre, Hope Hospital, Salford, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Hopkins
authors.forename: M
authors.initials: M
authors.lastname: Humphreys
authors.forename: M I
authors.initials: MI
authors.lastname: Jayson
mesh_terms: D001168:Arthritis / Q000276:immunology*; D001172:Arthritis, Rheumatoid / Q000276:immunology; D001681:Biological Assay; D006801:Humans; D007375:Interleukin-1 / Q000032:analysis*; D010003:Osteoarthritis / Q000276:immunology; D011863:Radioimmunoassay; D013582:Synovial Fluid / Q000276:immunology*
chemical_list: D007375:Interleukin-1