ANNEXIN-V AUTOANTIBODIES IN RHEUMATOID-ARTHRITIS

Objective-To investigate the occurrence of anti-annexin V autoantibodi es in sera of patients with rheumatoid arthritis to assess involvement with the disease and any relation to glucocorticoid treatment. Method s-Anti-annexin V antibodies were measured by an enzyme linked immunoso rbent assay (ELISA) which used the purified human recombinant protein as antigen. Results-Concentrations of anti-annexin V autoantibodies, p redominantly of the IgG class, were significantly raised in sera from patients with rheumatoid arthritis compared to normal controls. This w as not correlated with other indices of disease activity such as eryth rocyte sedimentation rate or C reactive protein and was unrelated to g lucocorticoid treatment. Conclusions-Extracellular annexin V provides an antigenic stimulus for autoantibody production and its in vivo expr ession is independent of glucocorticoid control. Such autoantibodies m ay have a detrimental role in the arthritic condition by interfering w ith putative functions of annexin V, including collagen type II bindin g, inhibition of phospholipase A(2) activity, and Fc receptor activity .