title: Inhibitors of interleukin 1 activity in synovial fluids and in cultured synovial fluid mononuclear cells.
abstract: Measurement of interleukin 1 (IL-1) in synovial fluids (SF) yielded variable results and implied the presence of an inhibitory activity. As peripheral blood monocytes produce an IL-1 receptor antagonist (IL-1ra), we investigated whether SF mononuclear cells (SFMC) also secreted such inhibitory activity. MC isolated from inflammatory SF produced, in addition to variable levels of IL-1, a specific IL-1 inhibitor of approximately 23 kDa which blocked both IL-1 biological activity and binding to its receptor. Western blot, using a polyclonal antibody to rhIL-1ra, indicated that SFMC secreted material that shared immunological crossreactivity with the cloned IL-1ra. IL-1 inhibitory activity was also detected in SF but not formally demonstrated to be related to IL-1ra. In conclusion, SFMC could produce IL-1ra and an imbalance between IL-1 and its specific antagonist may be relevant to the severity of joint destruction.
authors.affiliation: Division of Immunology and Allergy (Hans Wilsdorf Laboratory), University Hospital, Geneva, Switzerland.
authors.forename: P
authors.initials: P
authors.lastname: Roux-Lombard
authors.forename: C
authors.initials: C
authors.lastname: Modoux
authors.forename: T
authors.initials: T
authors.lastname: Vischer
authors.forename: J
authors.initials: J
authors.lastname: Grassi
authors.forename: J M
authors.initials: JM
authors.lastname: Dayer
mesh_terms: D015153:Blotting, Western; D002469:Cell Separation; D002478:Cells, Cultured; D002850:Chromatography, Gel; D006801:Humans; D007124:Immunoenzyme Techniques; D007375:Interleukin-1 / Q000037:antagonists & inhibitors* / Q000378:metabolism; D009000:Monocytes / Q000378:metabolism*; D011994:Recombinant Proteins; D013582:Synovial Fluid / Q000166:cytology / Q000378:metabolism*
chemical_list: D007375:Interleukin-1; D011994:Recombinant Proteins