THE INVOLVEMENT OF INTERDIGITATING (ANTIGEN-PRESENTING) CELLS IN THE PATHOGENESIS OF RHEUMATOID-ARTHRITIS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 51  (2) , 247-254
Abstract
Macrophage like cells expressing high concentrations of HLA-DR antigen were identified in situ within the synovium of patients with rheumatoid arthritis. The characteristics of these cells were determined using immunohistological analysis and combined cytochemical techniques. The majority (> 80%) of these cells were interspersed within the perivascular lymphocytic infiltrates occurring in the synovium. These cells did not stain with antisera against surface Ig or any Mc Ab [monoclonal antibodies] to T lymphocyte markers. Further combined staining demonstrated that the HLA-DR +ve cells did stain with an anti-monocyte monoclonal (FMC-17), but could not be stained with a Mc Ab against C3b [complement components 3b] receptors. The interfacing of cytochemical reactions for acid phosphatase (ACP) and ATPase with immunofluorescence staining for HLA-DR demonstrated that these cells were ACP-ve ATPase+ve. The HLA-DR +ve cells found in abundance in the rheumatoid synovium apparently, expressed identical characteristics to the interdigitating cells of the normal lymph node paracortex. The possible significance of the presence of large numbers of such antigen presenting cells in the rheumatoid synovium is discussed.