FIG. 2.
Results of L. amazonensis protection assays for mice immunized with rLACK-rA2-rIL-12. Groups of eight BALB/c mice were immunized with two subcutaneous injections at 15-day intervals with 50 μg of rLACK, rA2, or a combination of the two recombinant proteins in the left hind footpads and challenged with 106 late-log-phase L. amazonensis promastigotes in the right hind footpads, as described in Materials and Methods. rIL-12 (1 μg) was used as an adjuvant. Control mice received PBS. (A) Lesion development (footpad swelling) was monitored weekly with a caliper. Each point represents the average, and error bars represent standard deviations. (B) Parasite loads detected in infected footpads of each immunized group 9 weeks postchallenge. Numbers of viable parasites were determined by a limiting dilution assay as described in Materials and Methods. Each bar represents the average, and error bars represent standard deviations (n = 4). The asterisk indicates that differences are statistically significant (P < 0.05).