PRTN3 and rheumatoid arthritis: The study revealed that in high-risk individuals, serum ACPA concentration was positively correlated with the relative abundance of Eubacterium nodatum_group, Peptostreptococcus, Tannerella, norank_o__Absconditabacteriales_SR1, while conversely associated with Haemophilus and Neisseria (Figure 4A), both of which were significantly decreased in RA patients (Supplementary Figure 2).