Search for antigen in rheumatoid synovial macrophages

in rheumatoid synovial macrophages. Peripheral blood monocytes and synovial macro-phages obtained from 21 patients with rheumatoid arthritis and from 13 controls were cultured with autologous peripheral blood lymphocytes and stimulation measured by thymidine uptake. Rheumatoid macrophages and monocytes induced a small but significant degree of lymphocyte transformation, and those from the controls did not. The degree of stimulation appears to be more consistent with the nonspecific effect of lymphocyte activating factor, rather than with the presence of a specific synovial antigen. Macrophages play an important immunological role (Unanue, 1972) by presenting antigens to lymphocytes (Cline and Swett, 1968). Indeed, the macrophage-lymphocyte aggregate seen in tissue culture has been shown to be a site for passage of antigen to lympho-cyte (Bona and others, 1972) and for lymphocyte transformation (Sulitzeanu and others, 1971). Macro-phage-lymphocyte aggregates appear early in the lif