FIG. 7.
The live, attenuated vaccine confers more durable immunity than the nonlive vaccines. (A) Development of ear lesions in B/6 mice following live vaccination with 104 metacyclic promastigotes alone (•) or with 50 μg each of ALM and CpG ODNs (▪). Data represent the mean induration ± SD for six mice per group. (B) Development of ear lesions in mice challenged in the opposite ear by intradermal inoculation of 500 metacyclic promastigotes of L. major. Mice were unvaccinated (•) or vaccinated 6 months previously with CpG ODN and ALM (⧫), with antigen DNA (▪), or with live parasites plus CpG ODN and ALM (▴). Data shown represent the mean induration ± SD for three to six mice per group. (C) Parasite quantitation in the ear dermis at 4 (gray bars) and 20 (black bars) weeks postchallenge. Results are expressed as geometric mean ± SD for three mice per group.