Protection duration of i.n. LaSP-Ex upon a less virulent infection. BALB/c mice were vaccinated with LaSP-Ex and seven days after the booster animals were challenged with 2 × 105 at the beginning of stationary-phase L. amazonensis-GFP (4 days of culture) and monitored as described for Figure 1. A) Lesion sizes. B) Parasite loads were measured on day 125 of infection. Means ± SD (n = 5). *p ≤ 0.05 and #p ≤ 0.01 relative to PBS controls. The data displayed is representative of two independent experiments.