FIG 6.

Evaluation of protective efficacy of ESAT-6 by adjuvantation with PLG against M. tuberculosis infection. The mice were immunized by the i.p. route with antigen ESAT-6 either alone or with adjuvants. BCG vaccine was given at the time of the first immunization. Six weeks after the last immunization, the mice were challenged with a virulent strain of M. tuberculosis H37Rv by the i.v. route. (A) Four mice from each group were sacrificed at each time point after challenge, and the CFU in the lung and spleen were recorded. (i and ii) Lung (i) and spleen (ii) M. tuberculosis load at 3 weeks. (iii and iv) Lung (iii) and spleen (iv) M. tuberculosis load at 6 weeks. (B) Graphical representation of total granuloma score from each infected mouse group. (C) Survival of M. tuberculosis-infected mice (n = 12) from each group, monitored for death until 47 weeks. The results are presented as percent survival. One-way ANOVA followed by Tukey's multiple-comparison test was employed for calculating the statistical significance in CFU studies. To calculate the significance of difference in survival studies, the log-rank Mantel-Cox tests were applied. *, P < 0.05; **, P < 0.01; ***, P < 0.001; ****, P < 0.0001. n.s, nonsignificant.