Protective role of the pefloxacin-IFN-gamma association in Leishmania major-infected mice.

Four groups of female Balb/c mice were inoculated in the left hind footpad with 30 microliters of RPMI 1640 medium containing 10(7) Leishmania major amastigotes/ml. One group was injected sc with 200 microliters of RPMI 1640 containing 180 micrograms of pefloxacin for 20 days, a second group with the same amount of medium containing 100 units of recombinant murine interferon gamma (rmIFN-gamma). The third group was treated with the association, while the fourth group received plain medium in an identical regimen. Pefloxacin or IFN-gamma significantly decreased the size of primary lesions, while their association was significantly more efficient in this respect, in reducing the incidence of metastatic lesions, and in clearing parasites from the spleen. We also investigated the effect of pefloxacin on the activation of mouse spleen cells by Concanavalin A (Con A) in vitro, without detecting any interference on the proliferative response or IFN-gamma production.