Modulation of cartilage destruction in murine arthritis with anti-IL-1 antibodies.

One of the early events in murine antigen-induced arthritis is the generation of IL-1 in the inflamed joint. We investigated the role of IL-1 in the acute phase of the arthritic process by selective blockage of IL-1 bioactivity by treatment with neutralizing antibodies. Pretreatment with anti-IL-1 antibodies moderately suppressed joint swelling. The decrease in chondrocyte proteoglycan synthesis seen in the acute phase of arthritis was prevented by treatment with anti-IL-1 antibodies. IL-1 does not appear to be a major contributor to the accelerated breakdown of articular cartilage in this model. The major impact of anti-IL-1 antibodies was the prevention of proteoglycan synthesis inhibition which clearly reduced articular cartilage depletion by maintaining normal proteoglycan synthesis.