Restoration of immune response by levamisole in B-77 virus induced tumor-bearing rats.

The immunorestorative effect of levamisole was observed in Lewis rats inoculated with a syngeneic B-77 virus induced tumor and immunized with sheep erythrocytes. In tumor-bearing rats the cell-mediated cytotoxicity, the delayed footpad reaction and the antibody production were suppressed. While the cytotoxicity suppressed in tumor-bearing rats was not restored by levamisole, delayed footpad reaction and antibody production were enhanced as compared with the normal reaction, or were restored to normal levels by levamisole, respectively. Tumor growth was significantly suppressed in rats treated with levamisole. The presence of tumor changed the uptake of 3H-uridine labeled lymphocytes in the spleen and peripheral blood. Restorative effect of levamisole on T lymphocytes was different in the studied organs.