Selective inhibition of lymphocyte responsiveness to phytohaemagglutinin in patients with Reiter's syndrome.

The influence of synovial fluid from four patients with Reiter's syndrome on lymphocyte responsiveness was studied. On synovial fluid was found which specifically depressed the responsiveness of lymphocytes from patients with Reiter's syndrome to the non-specific mitogen phytohaemagglutinin (PHA). The ratio of the responsiveness of lymphocytes cultured in the presence of foetal calf serum (FCS), compared to those incubated in the Reiter's synovial fluid, was used as a measure of the depression induced by the Reiter's synovial fluid. The mean ratio for eight normals stimulated with PHA was 0-70 (range 0-35-0-96), while for eight patients with Reiter's syndrome, it was 0-13 (range 0-07-0-19). Similar studies done with concanavalin A (con A) showed no difference between lymphocytes from normals (0-73) or patients with Reiter's syndrome (0-67). Chromatography of the Reiter's synovial fluid on a Sepharose 4-B column resulted in the separation of three major fractions, one of which exhibited the inhibitory activity. When this active fraction was absorbed with Reiter's lymphocytes, a loss of the inhibitory activity of the fraction was seen. A similar absorption with normal lymphocytes had no effect. These studies demonstrate that a factor present in the synovial fluid of a patient with Reiter's syndrome reacted specifically with lymphocytes from patients with Reiter's disease and not with lymphocytes from normals. The interaction of this factor with lymphocytes from patients with Reiter's syndrome inhibited the responsiveness of these lymphocytes to PHA but not to con A.