Relationship between HLA-DR-expressing cells and T lymphocytes of different subsets in rheumatoid synovial tissue

An immunohistochemical double staining technique was used to study the relationships between HLA-DR-expressing, mostly macrophage-like cells, and different populations of T lymphocytes in frozen sections of synovial tissue from patients with inflammatory joint disease, particularly rheumatoid arthritis. Substantial T-lymphocyte infiltration as measured by Leu 1 antibody binding was found, especially adjacent to HLA-DR-expressing cells near the synovial cavity and around small vessels. Most of the T cells reacted with Leu 3a ('helper/inducer'-cell-specific) antibodies, whereas relatively few cells were Leu 2a ('cytotoxic/suppressor' T-cell-specific)-positive.