Fig 1. Antigen-specific IFNγ-secreting cells were induced systemically following immunisation with PLGA particulate vaccines.

C57BL/6 mice were immunised with 1 mg PLGA vaccine either i.n or s.c as indicated, three times at two-weekly intervals. At four weeks after the last vaccination, lymphocytes of vaccinated mice were stimulated ex vivo with MPT83 (10 μg/ml). The numbers of MPT83-specific IFNγ-secreting cells/10⁶ lymphocytes in the spleen or DLN of mice immunised with PLGA vaccines adjuvanted with (A) TDB or (B) MPL were enumerated by ELISPOT after 20 hr antigen stimulation. The data are the means ± SEM (n = 3) and are representative of two independent experiments. Statistical significance was calculated by ANOVA with Bonferroni post-hoc comparison to adjuvant only control (*p<0.05, ***p<0.001).