[Monocytes/macrophages in synovial tissue in chronic polyarthritis and arthrosis--differentiating from monoclonal...

Using monoclonal antibodies directed towards distinct cell surface antigens of the monocyte/macrophage lineage, we tried to disclose diagnostically relevant differences in the distribution pattern of monocytes and macrophages in cryostate sectioned synovial tissue samples from patients with rheumatoid arthritis and osteoarthrosis, psoriatic arthritis (n = 1) and a healthy control subject. As compared to osteoarthrosis, we found that in rheumatoid arthritis, accessory cells of the T- and B-cell immune response are pronounced in the basis areas of the superficial cell layers, indicating an active inflammatory process of immunological origin. Applying monoclonal antibodies specific for monocytes and immature macrophages of connective tissue, we confirmed the finding of an enhanced migration of those cells from the peripheral blood stream into the inflamed synovial tissue. Despite those findings, we were not able to demonstrate significant immuno-morphological differences between tissue from patients with rheumatoid arthritis and osteoarthrosis.