Figure 1
Induction of robust listeriolysin O (LLO)-specific mucosal CD4 T cells. (a–c) C57Bl/6 (B6) mice were orally infected with 2 × 109 colony-forming units (CFU) InlAM rLm and LLO-specific CD4 T cells were quantified and examined for α4β7 expression from the blood at the indicated times. Representative zebra plots and histograms are gated on live CD4 T cells (a) or live LLO-I-Ab+ CD4 T cells (c). Absolute numbers of circulating LLO-specific CD4 T cells were calculated per 1 ml of blood (b). Data are representative of three experiments with at least three mice per group. (d–h) B6 mice were orally infected with InlAM rLm and LLO-specific CD4 T cells were quantified from the spleen, mesenteric lymph nodes (MLN), lamina propria (LP), and intraepithelial lymphocyte (IEL) compartment after infection. (d) Representative zebra plots are gated on live CD4 T cells at 9 (primary) and 60 (memory) days post infection (d.p.i.), or 7 days after a secondary challenge of mice that were immunized 60 days previously (secondary). Numbers within quadrants correspond to the percentage of cells within gates. (e) The graph shows pooled data from five independent experiments with 15–17 mice total at 9 d.p.i. (primary). (f) The graph shows pooled data from three independent experiments with 12 mice total between 50 and 90 d.p.i. (memory). (g) The graphs showed pooled data from three independent experiments with 8–9 mice total at 7 days after secondary infection of mice immunized 60 days previously (secondary). (h) Absolute numbers of LLO-specific CD4 T cells were quantified in the spleen, MLN, LP, and IEL with tetramer enrichment and counting beads at the indicated time post infection. Mice were given a secondary challenge infection with oral InlAM rLm at 33 d.p.i. Data are representative of three independent experiments. All graphs depict the mean±s.e.m.
