Suppression of experimental allergic encephalomyelitis by tilorone: cell transfer and interferon studies.

Tilorone is known to induce interferon and to suppress experimental allergic encephalomyelitis (EAE) produced by active immunization. In the present work, tilorone was given to donors or recipients of the passive transfer form of EAE, using a localized variety of 1 or 4 days duration and a nonlocalized form of 8 days duration. The results indicated that tilorone inhibited EAE by retarding the clonal expansion in response to antigen, by a reversible inhibition of EAE effector cells, and probably by an effect on nonspecific reactive cells in the perivascular inflammatory infiltrates. Inhibition of EAE was not mediated by the induction of interferon, but was associated with depletion of T lymphocytes.