[Involvement of lymphocyte populations in rheumatoid synovial lesions]

T and B lymphocyte proportions have been studied in synovial fluid and peripheral blood from 70 patients with classical or definite rheumatoid arthritis (RA). The results have shown that T-cell numbers assessed by E-rosettes and anti-HTLA antiserum, B-cell numbers detected by membrane immunofluorescence and EAC-rosettes from peripheral blood were similar in RA and in a control group. Conversely, "active" E-rosettes which detected a subset of mature T cells, were decreased in blood and very increased in synovial fluid. Furthermore, the percentages of mononuclear cells bearing a Fc-receptor for IgG (EA-rosettes) were higher in synovial fluid than in RA peripheral blood. These data could be in favour of the cell-mediated immunity in rheumatoid arthritis lesions.