RELIMINARY STUDIES OF THE EFFECT OF LAVAMISOLE ON THE IMMUNE RESPONSE OF MICE INFECTED WITH LEISHMANIA

Abstract

The susceptibility of various strains of mice to infection by Leishmania tropica (major) was recently studied in this laboratory. The infection in A/J, C3H, CBA, AKR/J, AKR/CU, and C57B1 mice (the semi resistant strains) remained cutaneous and the animals recovered within 4-6 months. However BALB/c mice developed generalized infection after two months of exposure resulting in death 3-4 months later. When compared to the semi resistant strains, BALB/c mice exhibited a poor delayed hypersensitivity (DH) to Leishmania antigen, but a relatively higher humoral response. In this study, the effect of levamisole on modulation of cell mediated immunity, d well as regulation of disease in A/J and BALB/c mice was investigat6d and compared: 1. Thirty days after infection, the titer of antibody in levamisole treated A/J or BALB/c mice was similar to the corresponding untreated control. However, when compared to the controls, the magnitude of DH was decreased in levamisole treated A/J mice but partially increased in similarly treated BALB/c mice. The course and severity of infection was influenced by levamisole treatment in A/J mice. Forty-eight days after infection, approximately 45% of the control mice as compared to 5% of the treated animals exhibited cutaneous ulcers. Furthermore, the mortality rate in the control animals was 27%, whereas, none of the treated. A/J mice died during this period. Similarly 48 days after infection. 100% of the untreated control BALB/c mice and 65% of the, levamisole treated animals developed ulcers. The drug, however, had no effect on the death of the infected BALB/c. Levamisole in doses 2-8 times higher than that used In vivo had no effect on the In vitro proliferation of the organism.