Fig. 6

Collinsella aerofaciens enhances arthritis severity. Two weeks post-immunization (marked with arrow) a subset of mice were treated with C. aerofaciens every alternate day for 4 weeks (marked with arrows), n = 10. Mice not treated with C. aerofaciens (n = 8) were used as a control. Mice were followed for a incidence and onset of arthritis (*P = 0.068) and b disease severity. Collinsella enhances T-cell proliferation. c T-cell proliferation was measured by culturing sorted (by fluorescence-activated cell sorting) CD4 cells from the spleens of CII-primed mice cultured with dendritic cells that were pre-cultured with Collinsella for 4 h. **P = 0.02 (n = 3 mice/group). Collinsella reduces the expression of the tight junction protein ZO-1 and Occludin. d CACO-2 cells cultured with or without Collinsella stained with ZO-1 and Occludin showed differences in the expression of tight junction proteins. e Quantification of the mean fluorescence intensity of ZO-1 and Occludin expression in CACO-2 cells cultured alone or in the presence of Collinsella, ^# P < 0.05 and *P < 0.01. f Increased gut permeability was observed in DQ8 mice when Collinsella was administered. Sera of mice were tested for FITC-Dextran before and after treating mice with Collinsella for 3 weeks (*P = 0.03; n = 10 mice/group). g Fold difference in the expression of Th17 regulatory cytokine/chemokine transcripts in CACO-2 cells cultured with C. aerofaciens compared with CACO-2 cells cultured with bacterial growth media. Error bars represent standard error of the mean values. Experiments were repeated for reproducibility