VERMICULINE-INDUCED DECREASE IN CYTOKINE PRODUCTION BY HUMAN-LEUKOCYTES

Vermiculine, a macrocyclic aglycosidic dilactone isolated from Penicil lium vermiculatum, was shown to have an inhibitory effect on the abili ty oi concanavalin A to induce cytokine production in unseparated peri pheral blood leukocytes (whole blood cultures). Vermiculine inhibited the production of (FN-gamma > IL-2 > TNF > IL-6. However ils effect on IFN-gamma and IL-2 was found to be bimodal. The suppressive effect of vermiculine was manifested at low concentrations (0.01 to 1.0 mu g/ml ) of the agent and an increased production oi cytokines was observed w hen the highest concentration oi the agent (10 mu g/ml) was used. Verm iculine suppression of IFN-gamma production by unseparated leukocytes from healthy donors and from patients with rheumatoid arthritis exhibi ted a difference of about 2 to 20%.