Effects of gold sodium thiomalate on murine spleen cells

The effects of gold sodium thiomalate (GST) on Balb/c murine spleen cells were investigated using in vitro mitogen blastogenesis techniques. Initial culture of spleen cells in the presence of concanavalin A (Con A) and GST exhibited inhibition of 3H-thymidine uptake due to gold. Spleen cells depleted of monocytes/macrophages by carbonyl iron-ingestion and cultured with Con A and GST demonstrated biphasic effects by gold on thymidine uptake depending upon the Con A and GST concentrations. A final concentration of 2.5 μg/ml con A showed a decreased inhibition of blastogenesis by gold, with macrophage depleted cells as compared to intact spleen cells. While a final concentration of 0.5 μg/ml Con A showed an increased inhibition of blastogenesis by gold with macrophage depleted cells as compared to intact spleen cells. GST was found to be most effective at inhibiting proliferation when present at the initiation of culture. GST was also found to inhibit responsiveness of cells previously incubated with mitogen and its presence in the culture media was required for at least 24-36 hours to produce significant inhibition. These results indicate that the greatest effects of GST on blastogenesis occur during the initial steps of lymphocyte activation and that macrophages may not be the only cell of gold action