Study links intestinal bacteria to rheumatoid arthritis

Researchers have linked a species of intestinal bacteria known as Prevotella copri to the onset of rheumatoid arthritis, the first demonstration in humans that the chronic inflammatory joint disease may be mediated in part by specific intestinal bacteria. The new findings by laboratory scientists and clinical researchers in rheumatology at NYU School of Medicine add to the growing evidence that the trillions of microbes in our body play an important role in regulating our health.
Using sophisticated DNA analysis to compare gut bacteria from faecal samples of patients with rheumatoid arthritis and healthy individuals, the researchers found that P. copri was more abundant in patients newly diagnosed with rheumatoid arthritis than in healthy individuals or patients with chronic, treated rheumatoid arthritis. Moreover, the overgrowth of P. copri was associated with fewer beneficial gut bacteria belonging to the genera Bacteroides.
‘Studies in rodent models have clearly shown that the intestinal microbiota contribute significantly to the causation of systemic autoimmune diseases,’ says Dan R. Littman, MD, PhD, the Helen L. and Martin S. Kimmel Professor of Pathology and Microbiology and a Howard Hughes Medical Institute investigator.
‘Our own results in mouse studies encouraged us to take a closer look at patients with rheumatoid arthritis, and we found this remarkable and surprising association,’ says Dr. Littman, whose basic science laboratory at NYU School of Medicine’s Skirball Institute of Biomolecular Medicine collaborated with clinical investigators led by Steven Abramson, MD, senior vice president and vice dean for education, faculty, and academic affairs; the Frederick H. King Professor of Internal Medicine; chair of the Department of Medicine; and professor of medicine and pathology at NYU School of Medicine.
‘At this stage, however, we cannot conclude that there is a causal link between the abundance of P. copri and the onset of rheumatoid arthritis,’ Dr. Littman says. ‘We are developing new tools that will hopefully allow us to ask if this is indeed the case.’ NYU Langone Medical Center