LEISHMANIA-MEXICANA IN C3H MICE - BCG AND LEVAMISOLE TREATMENT OF ESTABLISHED INFECTIONS

Abstract

The effect of BCG and levamisole on the course of established murine leishmaniasis was examined. C3H mice infected s.c. in the perinasal region with 105 L. mexicana promastigotes produced chronic non-ulcerating, non-healing lesions and demonstrated positive humoral and delayed hypersensitivity responses to leishmanial antigens. Infected animals were treated during months 3-5 of infection with live BCG or with levamisole. Neither treatment resulted in resolution of lesions or in production of a hyperallergic form of infection; neither immune responses to leishmanial antigens nor histopathological features of lesions were significantly altered. BCG treatment resulted in accelerated growth of primary leishmanial lesions and in the appearance of metastases in some animals. Levamisole treatment of uninfected animals resulted in low levels of antibodies reacting with promastigote antigens, but not in positive delayed intradermal responses. BCG induced delayed intradermal sensitivity to PPD [purified protein derivative] in infected and control animals; significantly increased delayed reactions to leishmanial antigens and occasional low levels of cross-reacting antibodies to Leishmania were observed in treated uninfected mice.