Figure 3

<p>Phenotypic characteristics of non-treated (control) or bacteria-pulsed BMDCs from BALB/c mice. Plots show flow cytometric profiles of MHC class II, CD86 and CD40 expression (thick line) in comparison to an isotypic control (thin line). The data are representative of 4 independent experiments.</p

Figure 8

<p>Result of the <i>in vivo</i> administration of anti-CD25 mAb (PC61) on the protective effect of probiotic-pulsed BMDCs in TNBS-induced colitis. Ten mice per group were challenged with TNBS alone (CTL) or after Lr32-pulsed BMDC transfer (Lr32-DC). The effect of a pre-treatment by either 200 µg of anti-CD25 (α-CD25) or control rat IgG (rat IgG) mAb, 24 h before colitis induction was analyzed in mice treated or not by Lr32-pulsed BMDC (Lr32-DC) transfer. Wallace inflammation scores (mean ± SEM) were calculated in each group and compared to each other by a Mann-Whitney U test (<0.01, **; p<0.001, ***). Percent of mortality and protection (reduction of the mean Wallace scores of mice treated with BMDCs, in relation to the mean score of TNBS control group) are also reported.</p

Immuno-modulatory and protective properties of strains used in the study

a<p>IL-10/IL-12 ratio was previously determined by the capacity of the strains to induce IL-10 and IL-12 after <i>in vitro</i> PBMC stimulation and ^b protection indicated the capacity of the strains to protect mice from TNBS-induced colitis</p

Figure 4

<p>Protective effect of intra-peritoneal administration of LAB-treated BMDCs on acute TNBS-induced colitis in BALB/c mice. Wallace inflammation scores were calculated after a TNBS challenge in mice either not treated (None) or intraperitoneally injected by untreated BMDCs (DC) or BMDCs treated with (A) Lr32 (Lr32-DC) or (B) Ls33 (Ls33-DC) strains. The comparison between the TNBS-control groups and the groups that received the corresponding untreated BMDCs (DC) was calculated using the Mann-Whitney U test (<0.01, **; p<0.001, ***). Percentage mortality and protection (reduction of the mean Wallace scores of mice treated with BMDCs, in relation to the mean score of TNBS control group) are also indicated. In A, the effect of Lr32-treated BMDCs was also compared to the intra-peritoneal administration of 10⁸ CFU of Lr32 bacteria (Lr32-IP) and in B, an additional group of mice was included, pre-treated with 3 intra-peritoneal administrations of prednisone (10 mg/kg), representing a clinically relevant standard treatment for Crohn's disease (36). Data represent the mean±SEM of two representative experiments (number of mice n = 10).</p

Figure 2

<p>Cytokine (A) and chemokine (B) response of murine BMDCs (0.5×10⁶ cells/ml) derived from BALB/c mice to stimulation with strains <i>L. rhamnosus</i> Lr32, <i>L. salivarius</i> Ls3<i>3, L. acidophilus</i> NCFM, <i>L. lactis</i> MG1363 and <i>E. coli</i> TG1. Bacteria were collected after overnight culture and the stimulation of BMDC was done at a ratio of 10∶1 (bacteria/DC). Results represent the mean±SEM of 7 independent experiments.</p

Figure 7

<p>Quantitative real time PCR analysis of mRNA expression of pro-inflammatory or regulatory mediators in colons obtained 48 h after TNBS-induced colitis. Mice were left untreated (None) or IP administered with untreated BMDC (DC) or Lr32-treated BMDCs (Lr32-DC). The values are expressed as the mean ratio±SEM of mRNA levels after TNBS challenge compared with non challenged healthy mice.</p

Figure 1

<p>Internalization of <i>L. rhamnosus</i> by BMDCs. BMDCs were incubated for 18 h with Lr32 strain at a bacteria-to-DC ratio of 10 and then processed for transmission electron microscopy. Bacteria are visible within membrane-bound phagosomes at various stages of degradation (arrows). Bar, 2 µm.</p

Figure 5

<p>Representative histology of May-Grunwald stained sections (×10) of the distal colon from healthy control mice (A), mice with acute TNBS-induced colitis that have been or not (B) administered with non-treated DC (C) and Lr32-treated DC (D) and corresponding Ameho scores (E), mean±SEM (number of mice n = 10).</p