[Synovial level of interleukin 1 and C3a in chronic polyarthritis, psoriatic arthritis and activated arthritis].

Concentrations of interleukin-1 (IL-1), C3a des Arg and immune complexes (IC) were investigated in knee effusions of patients with rheumatoid arthritis (RA; n = 36), psoriatic arthritis (Ps.A., n = 19) and osteoarthritis (n = 7). Maximal concentrations of IC and C3a des Arg were found in RA patients, high IL-1-activities could be demonstrated in patients with Ps.A. and seropositive RA. We found significant correlations between IL-1 and C3a des Arg, IL-1 and IC and C3a des Arg, and IC in Ps.A. patients, but not in RA or osteoarthritis patients. The role of IL-1 in the chronic inflammatory response and joint destruction in inflammatory joint diseases is discussed.