Eluted rheumatoid synovial tissue T cell subsets and HLA-DR bearing cells at different stages of fractionation.

By using monoclonal antibodies of the OK series in the indirect immunofluorescence technique we wanted to enumerate T cell subsets and HLA-DR-bearing cells of patients with classical rheumatoid arthritis after the cells were eluted from rheumatoid synovial tissue and at different stages of two cell fractionation procedures. The procedures were an overnight incubation on plastic flasks or a brief (7 min) fractionation on nylon wool columns, both followed by Isopaque-Ficoll gradient centrifugation. 70-90% HLA-DR+ cells and 15-30% T3+ (T cells) were initially observed. Plastic flask incubation and gradient centrifugation reduced the mediam number of HLA-DR+ cells to 55% while the number of T3+ cells increased to 60-75%, the number of T4+ (helper/inducer T cells) and T8+ (cytotoxic/suppressor T cells) usually being about equal. The other fractionation procedure left essentially the same relative proportions of cells bearing these markers even though the cell yield was 5-10 times greater than for the plastic flask fractionation. About 30% of the T cells were calculated to bear HLA-DR antigens, indicating local activation in vivo.