Selective T cell response of vaccinated mice 3 and 5 days post LVS lethal challenge.

a Number of IFNγ secreting cells/106 splenocytes were removed at the indicated day post challenge (see Materials and Methods). Data represents mean and SD from 3 individual animals (per group) derived from 2 independent experiments. b 107 CFU/ml of formalin-inactivated LVS (see Materials and Methods). c 10 µg of anti-CD4 antibodies were added to 106 splenocytes 1 hour before stimulation with formalin inactivated LVS. d 10 µg of anti-CD8 antibodies were added to 106 splenocytes 1 hour before stimulation with formalin inactivated LVS. e Samples from harvested spleens were taken for the evaluation of bacterial load, which was determined by real time-PCR or CFU counts (see Fig. 3A). f Survival data are derived from 3 groups of 10 mice each at 28 days post challenge (see Fig. 2A). g Mice were challenged i.p. (14 days following the last immunization) with 103 CFU of LVS (equivalent to 10 LD50).