Marker and functional characterization of immunoregulatory cells in rheumatoid arthritis.

In 34 patients with rheumatoid arthritis we determined the regulatory index OKT 4: OKT 8 and the suppressor index delta 24: delta 0. There is no correlation between the results of the detection of subpopulations with monoclonal antibodies and of the functional test to determine the suppressor activity. The enhanced mitogen-induced proliferation after 24-h preincubation is regularly associated with a rise in the regulatory index; however, without convincing quantitative correlation. It can be concluded, that only a small portion of the cell population identified by monoclonal antibodies OKT 4 and OKT 8 exerts helper or suppressor activities. At present, identification of regulatory T-cell subpopulation should be complemented by functional tests.