The stimulation of IL-2 production by anti-rheumatic drugs.

IL-2 release from mouse splenocytes was measured by assaying the IL-2 on an IL-2-dependent cytotoxic T-lymphocyte line in culture (CTLL). Proliferation of the CTLL cells was monitored indirectly with the dye thiazolyl blue. The slow-acting anti-rheumatic drug auranofin at concentrations below 0.1 microM potentiated concanavalin A (Con A)-induced IL-2 release. Similar potentiation of Con A-induced IL-2 release was obtained with D-penicillamine, 1 microM-1 mM, and with the angiotensin-converting enzyme-inhibitor captopril, 10 nM-1 microM. Potentiation of Con A-induced IL-2 release was obtained with concentrations of the drugs likely to be achieved in vivo during therapy. Auranofin but not D-penicillamine and captopril inhibited Con A-induced IL-2 release at high concentrations (greater than 0.3 microM).