Dysbiotic oral and gut viromes in untreated and treated rheumatoid arthritis patients

Background Rheumatoid arthritis (RA) has been considered to be influenced by bacteria from the oral cavity and gut for many years. Despite potential impact of viruses in RA was mentioned in some studies, specific roles of oral and gut viromes in RA is still unclear. Results In this study, we observed the viral community variation in the oral and gut samples, performed a comparative analysis of oral and gut viromes in health controls, untreated and treated RA patients, and constructed interaction networks among viruses, bacteria, and RA-associated clinical indexes to address the potential associations between viral community and RA. The results showed that the viromes could be isolated from dental plaque, saliva, and feces samples, among which the saliva having the highest with in-sample diversity. Meanwhile, remarkable variations of viral diversity and composition in the oral (i.e., dental plaque and saliva) virome could be observed in RA patients and healthy controls yet in untreated and treated RA patients, with a relatively low variability in the gut virome. Distraction of viruses-bacteria interaction network was discovered in three sites of RA patients. In addition, some RA-associated oral taxa, including Lactococcus phage vOTU70, Bacteroides vulgatus, Lactococcus lactis, Escherichia coli, Neisseria elongate , were correlated to the RA-related clinical indexes. Conclusion Whole-virome analysis illustrated the potential role of oral and gut viral communities in the development of RA.