FIG. 2.
Vaccination of BALB/c mice with SLA in the presence of CD40L. Mice were vaccinated and boosted twice with cells expressing CD40L in combination with 50 μg of SLA (open squares). Infections in mice vaccinated with 50 μg of SLA with untransfected control cells (grey triangles) or mock vaccination with saline (solid circles) were also examined. Mice were challenged with 5 × 105 L. major promastigotes in the footpad, and the course of the disease was monitored by measuring footpad swelling twice weekly with a metric caliper. Results are presented as differences in footpad thickness between the infected and noninfected footpads. (Inset) At week 8, mice were sacrificed and parasite numbers (burdens) in the footpads were measured. The values shown are means ± standard deviations of five mice per group. Statistical significance at the 95% confidence level (P ≤ 0.05), determined by the Student's t test, is denoted by an asterisk.