Isolation of interleukin 1 from joint fluids of patients with Lyme disease.

To investigate the role of interleukin 1 (IL-1) in Lyme arthritis we assayed synovial fluids (SF) for the presence of IL-1 activity. Crude SF from patients with Lyme disease showed IL-1-like activity. Chromatography of joint fluids revealed activity at 15-20,000 daltons. Two populations of cells were grown, which produced significant IL-1 activity when stimulated with the Lyme disease spirochete or its lipopolysaccharide. IL-1 activity from SF or stimulated cells was neutralized with an antihuman IL-1 antibody. Our results suggest IL-1 is important in the pathogenesis of Lyme arthritis, and is similar to other arthritides.