The M. tuberculosis Phosphate-Binding Lipoproteins PstS1 and PstS3 Induce Th1 and Th17 Responses That Are Not Associated with Protection against M. tuberculosis Infection
Figure 3
Cell proliferation in response to PstS1 or PstS3 proteins in spleen cells of immunized mice. Pooled spleen cells (3 mice/group) of mice vaccinated with PstS3 antigen (panels (a), (c), and (e)) or with PstS1 antigen (panels (b), (d), and (f)) were cultured at cells/well and re-stimulated ex vivo with PstS1 or PstS3 proteins (5 μg/mL each) for 5 days before measuring thymidine incorporation in proliferating cells ((a) and (b)) or for 4 days before measuring CFSE dilution in replicating CD4+ ((c) and (d)) or CD8+ T cell populations ((e) and (f)). Data were combined from 3 independent experiments and are presented as mean. Error bars indicate SEM. The level of statistical significance for differences in each group of immunized mice was determined by a two-tailed Student’s t-test (; PstS1 or PstS3 stimulation versus unstimulated cells; §between PstS1- and PstS3-induced responses in each group; °between antigen-specific responses observed in mice immunized with DNA or protein alone).
