Adjuvant polyarthritis. II. Suppression by tilorone.

Tilorone (5-35 mg/kg/day) suppressed the development of adjuvant-induced arthritis and the concurrent development of cell-mediated immune response to a secondary immunogen(EL4 cells) in a dose-related manner. Its influence on the development of the humoral immune response tp EL4 cells was found to be dependent on dosage: stimulatory at low doses (7.5 and 11.0 mg/kg/day), but inhibitory at high doses (24.0 and 35.0 mg/kg/day). Single doses of tilorone (30-300 mg/kg), administered at 24 hours or 1 hour before the injection of carrageenan, suppressed the development of acute inflammation in the rat. Evidence is presented that neither the anti-inflammatory effect of tilorone, nor its influence on the immune response could account for its antiarthritic effect. It appears plausible that the compound may act via interferon induction.