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).