Fig. 7

The relationship among the gut microbiota, metabolites and immune cell in RA. A The correlation network graph showed the main interactions between gut microbiotas and their metabolites (Spearman’s correlation analysis, r > 0.5, P < 0.05). Gut microbiotas were marked in purple and metabolites were marked in red. The Solid connecting lines indicated the positive correlations between gut microbiotas and their metabolites, while dashed connecting lines indicated negative correlations between the two. Thicker lines indicated greater correlation values. It showed that arachidonic acid seemed to be the core metabolite as it was positively associated with six gut microbiotas enriched in RA including Ruminococcus 2, Staphylococcus, Staphylococcaceae, Bacillales, Lactobacillus, and Lactobacillaceae. B The correlation heatmap of altered gut microbiotas and their metabolites in RA with the expression of Th17, Treg, c-Tfr, and c-Tfh cells in new-onset RA patients. (RA: rheumatoid arthritis; Th17: helper T 17 cells; Treg: regulatory T cells; Tfr: follicular regulatory T cells; Tfh: follicular helper T cells)