FIG. 5.
Body weight loss and pulmonary bacterial load of mice immunized with UV-EB- and CpG-pulsed DC. DC were left untreated or incubated with live EBs, UV-EB, CpG, or UV-EB and CpG for a total of 48 h at 37°C. DC were washed with endotoxin-free PBS, and a total of 0.5 × 106 DC were injected into the intraperitoneal cavities of mice, which were separated into experimental groups of five mice. Animals were boosted with an identical dose of DC on day 14 and finally challenged intranasally on day 21 with 3,000 IFU of live EBs. Immune protection was determined by daily measurement of body weight after the final challenge (A) and the determination of pulmonary IFU counts on day 8 postchallenge (B). All experiments were performed on three separate occasions, with similar results. Results represent the mean ± SD from one representative experiment. *, P < 0.01; and **, P < 0.001 (both comparing UV-EB-pulsed DC and UV-EB- and CpG-pulsed DC).