Self-associating IgG rheumatoid factors isolated from three patients with rheumatoid arthritis activated human monocytes to release prostaglandin E
2 as well as a previously described mononuclear cell factor, which stimulates human synovial cells to release additional prostaglandin E
2 and collagenase. Thus, the immune complexes composed of self-associating IgG rheumatoid factors can contribute to the processes that destroy cartilage and bone in patients with rheumatoid arthritis.
Key words Self-associating IgG rheumatoid factors - Mononuclear cell factor - Human synovial cells - Collagenase - Prostaglandins - Rheumatoid factor