Study of lymphoid cells from inflamed synovial membranes.

Synovectomy specimens from patients with rheumatoid arthritis were cultured and after 24 hours the nonadherent cells were removed. These were found to include cells with the morphological characteristics of lymphocytes. Using the sheep-cell rosetting test, up to 94% of these cells were found to be T cells, and while T cells could be found in all the supernatant cell populations studied, not all made a mitogen response. None or only a very small number of B cells were found by staining for surface immunoglobulin. The possible roles which T lymphocytes might play in chronic inflammation in the rheumatoid synovium are discussed in relation to experimental work, and factors which attract T cells into areas of nonspecific inflammation are similarly considered in the light of animal experiments.