Immunomodulatory activity of recombinant IL-1 receptor (IL-1-R) on models of experimental rheumatoid arthritis.

Given the role of IL-1 in inflammation and in autoimmune diseases, studies were designed to examine the ability of IL-1 receptor (IL-1-R) to suppress inflammation in a model of chronic degenerative joint disease of adjuvant arthritis (AA) in Lewis rats and to suppress the development of a systemic lupus erythematosus (SLE)-like disease in MRL/lpr mice. IL-1-R was able to prevent the onset of the AA and, even if therapy started after the establishment of AA, the cytokine receptor was still able to reduce the degree of chronic inflammation and arrested its progress. Treating MRL/lpr mice with IL-1-R resulted in a decrease in the amount of autoantibodies and inhibited joint inflammation. Even in the established disease IL-1-R could reduce rheumatoid factors (RF) and autoantibodies, and the signs of a polyarthritis were inhibited.