Effect of tilorone hydrochloride on the lymphoid and interferon responses of athymic mice.

Nude athymic mice, which lack T-lymphocytes and are unable to mount a cellular immune response, failed to develop the lymphopenia so characteristically produced by a 100 mg/kg oral dose of tilorone hydrochloride in normal mice. The antiviral activity detected in athymic mice 18 hr after a 150 mg/kg oral dose of tilorone was significant, although somewhat less than that found in treated normal mice. These findings suggest that tilorone hydrochloride has a specific effect on T-lymphocytes that accounts for its effect on cellular immunity, but that its antiviral activity is not primarily mediated by T-lymphocytes.