The effect of gold salts on the phagocytic activity of synovial macrophages in organ culture.

The effect of the gold salt, gold sodium thioglucose, has been studied on the phagocytic activity of tissue macrophages in synovium excised from patients with rheumatoid arthritis (RA) and maintained as explants in organ culture. Specimens of synovial membrane were taken for culture from synovial tissue excised from the knee joints of 22 patients with RA undergoing surgery and 14 menisectomy controls. Glass coverslips coated with yeast were placed on the synovium and the specimens maintained in organ culture. The phagocytic activity was assessed by counting the percentage of macrophages containing yeast on the coverslip removed after 24 hr in culture. The effect of gold salts was assessed by adding gold sodium thioglucose at concentrations of 3 and 30 microgram/ml to the medium, and using sodium thioglucose as an additional control. Results (means %) indicated significantly higher phagocytic activity in RA macrophages (68.6) compared with controls (40.1), p smaller than or equal to 0.001. Gold thioglucose significantly suppressed phagocytosis at 3 microgram/ml (48.0) p smaller than 0.01, and at 30 microgram/ml (47.7) p smaller than 0.02 in RA but had not effect on control synovium. Sodium thioglucose had no significant effect on phagocytosis at either concentration on RA synovium.