Effects of levamisole on spontaneous rosette-forming cells in murine spleen.

Levamisole, an anti-anergic chemotherapeutic agent, is shown to depress the azathioprine sensitivity of rosette-forming cells (RFC) in the spleen of normal mice, and to restore the azathioprine sensitivity of RFC in the spleen of adult thymectomized mice. Using the fully active dose of 1.25 mg/kg i.v., the restoration effect was present 15 h after treatment with the drug and almost disappeared after 48 h. Levamisole was ineffective on RFC in vitro. These results suggest that Levamisole might interfere with the reactivity of T lymphocytes as has been described for drugs interfering with cyclic nucleotide metabolism.