Modulation of the pattern of development of experimental disseminated leishmaniasis by Corynebacterium parvum.

BALB/c mice are extremely susceptible to Leishmania major. In this mouse strain, the parasite multiplies progressively and rapidly disseminates to distant visceral and cutaneous sites. The present studies show, however, that if BALB/c mice are infected with the L major as an admixture with formalin-killed Corynebacterium parvum, they rapidly acquire the capacity to restrain the multiplication of the parasite at the site of inoculation, and prevent its dissemination to distant visceral sites. Moreover, admixture-treated mice subsequently develop systemic resistance to reinfection. Although the ability of C parvum to activate nonspecific microbicidal mechanisms of macrophages may be involved, the requirement that the adjuvant be given with the parasite inoculum is interpreted to suggest that C parvum facilitates the development of a protective immune response to the parasite.