Rheumatoid factors in immune complexes of patients with rheumatoid arthritis.

Abstract

Substantial evidence indicates that humoral immunity through antigen-antibody complex formation contributes to the pathogenesis of RA. Several studies have examined the composition of immune complexes present in the synovial fluid of patients with RA. The constituents of these immune complexes have been immunoglobulins and complement components. Only a few polypeptides in these immune complexes have not been identified. These unidentified components account for only a few percent of total proteins present. These results suggest that rheumatoid factors and their antigens are quantitatively the important ingredients of immune complexes in synovial fluid of patients with RA. The immune deposits in the superficial layers of articular cartilage from patients with RA contain RFs and antibodies to type II collagen.