POTENTIATION OF L1210 MURINE LEUKEMIA VACCINE INVIVO BY LEVAMISOLE

  • 1 January 1979
    • journal article
    • research article
    • Vol. 70  (4) , 515-519
Abstract
I.p. inoculation of either levamisole or 2 .times. 106 cells of concanavalin (con)A-bound L1210 leukemia vaccine produced no cured mice after subsequent i.p. inoculation of 103 live L1210 cells. Combined inoculation of levamisole and con-A-bound vaccine produced about 20% cure incidence but no prolongation of life span of tumor-bearing mice after inoculation of live L1210 cells. Combined inoculation of levamisole and con A-free vaccine did not induce detectable immune resistance in mice. Levamisole appa rently enhanced host response to cell-bound con-A associated with immunogenic potency of the vaccine. Levamisole given i.v. and orally was as effective as that inoculated i.p. in enhancing the induction of resistance in mice by con-A-bound vaccine. Dose of levamisole was very critical for this enhancement, being effective at 0.38 mg/kg but not at 0.75 or 0.19 mg/kg. Levamisole restored immune resistance induced by a larger inoculum of con-A-bound vaccine cells (107) and impaired by cyclophosphamide.