The M. tuberculosis Phosphate-Binding Lipoproteins PstS1 and PstS3 Induce Th1 and Th17 Responses That Are Not Associated with Protection against M. tuberculosis Infection

Table 1

Effects of different immunizations with the mycobacterial antigen Ag85B on protection against Mycobacterium tuberculosis challenge and antigen-specific immunity in mice.

Immunizations^a	IgG titer^b	Cell proliferation (cpm)^c	IFN-γ (pg/mL)^d	IL-17 (pg/mL)^e	−Δ CFU(log)/protection^f	Reference^g
DNA x2	800±200	3500±300	450±30	0±0	−0.7/yes	[3]
DNA x4	2000±350	3937±1064	559±60	0±0	−0.74/yes	[3]
DNA/protein-LTK63	43053±4746	22037±2695	6214±168	320±52	−0.32/yes	[4]
protein-LTK63	64507±12388	16714±326	3839±150	420±90	−0.31/yes
protein	2800±542	7579±645	333±100	10±5	−0.02/no	[3]
BCG					−1.1/yes	[3, 4]

^amice (5 mice/group) were immunized with Ag85B according to Figure 1, and some mice challenged also with M. tuberculosis H37Rv.
^bsera of immunized mice recovered 4 weeks from the last immunizations were analyzed by ELISA for the presence of anti-Ag85B Ab using a conjugated secondary Abs specific total IgG. Data are plotted as geometric mean ELISA titer ± SEM of 3 independent experiments.
^cspleen cells of Ag85B-immunized mice were cultured at 4×10⁵ cells/well and re-stimulated ex vivo with Ag85B protein (5 μg/mL) for 5 days before measuring thymidine incorporation in proliferating cells. Cell proliferation data are represented as mean cpm (subtracted from the cpm of unstimulated spleen cells) ± SEM of 3 independent experiments.
^dspleen cells of Ag85B-immunized mice were cultured at 4×10⁵ cells/well and re-stimulated ex vivo with Ag85B protein (5 μg/mL) for 4 days before measuring in cell culture supernatants IFN-γ by a specific ELISA kit. IFN-γ data are represented as mean (pg/mL) ± SEM of 3 independent experiments.
^espleen cells of Ag85B-immunized mice were cultured at 4×10⁵ cells/well and re-stimulated ex vivo with Ag85B protein (5 μg/mL) for 4 days before measuring in cell culture supernatants IL-17 by a specific ELISA kit. IL-17 data are represented as mean (pg/mL) ± SEM of 3 independent experiments.
^fAfter 4 weeks from M. tuberculosis challenge, the bacteria in the lung of infected mice were enumerated as described in Materials and Methods. Data are expressed as the Δ in CFU/lung (log) between vaccinated and unvaccinated control mice and it is indicated whether or not the vaccination was protective against M. tuberculosis challenge.
^gReference reporting some of the data.