Fig. 1

RA pathogenesis is prevented by oral administration of F. prausnitzii in CIA mice. A Timeline of the immunization and F. prausnitzii administration procedure. B The arthritis clinical score and incidence were reduced after oral F. prausnitzii administration in CIA mice. Arthritis was observed twice a week from week 3 to week 10, which is indicated on the X-axis (w = week). C Mice were sacrificed after 10 weeks F. prausnitzii administration and feces were collected. Quantitative PCR results showing elevated F. prausnitzii abundance in the feces of F. prausnitzii-treated mice. D Microscopy images of histologic sections of hind leg joints of Vehicle and Faecali group mice stained with hematoxylin and eosin (H&E) and safranin O. H&E images were displayed at × 40 magnification and safranin O images at × 200 magnification, respectively. The data are means ± standard deviation (n = 5). *p < 0.05 and **p < 0.01