Patients with Crohn’s disease, a type of inflammatory bowel disease (IBD) that causes abdominal pain and diarrhea, can also experience joint pain. In Crohn’s disease, which affects about 800,000 Americans, the immune system can attack not only the bowels, but the musculoskeletal system as well, leading to spondyloarthritis, a painful condition that affects the spine and joints. Now new research, published Feb. 8 in Science Translational Medicine, helps explain the connection between these seemingly unrelated symptoms, and could help physicians identify Crohn’s disease patients who are more likely to develop spondyloarthritis, enabling them to prescribe more effective therapies for both conditions.
New technology helped the researchers identify a type of E. coli bacteria found in people with Crohn’s disease that can trigger inflammation associated with spondyloarthritis, according to the study led by principal investigator Dr. Randy Longman and scientists from the Jill Roberts Center for Inflammatory Bowel Disease at NewYork-Presbyterian and Weill Cornell Medicine and theJill Roberts Institute for Research in Inflammatory Bowel Disease at Weill Cornell Medicine, microbiologists at Cornell University and rheumatologists at Hospital for Special Surgery.
The researchers used fecal samples from patients with IBD to identify bacteria in the gut that were coated with antibodies called immunoglobulin-A (IgA) that fight infection. Using flow cytometry, in which fluorescent probes are used to detect IgA-coated bacterial species, the researchers discovered that IgA-coated E. coli were abundant in fecal samples from patients with both Crohn’s disease and spondyloarthritis. Using both patient samples and mouse models, they then linked these bacteria to cells that help regulate inflammation, known as Th17 cells, in people with autoimmune disorders.
“Our findings may allow us to develop diagnostic tools to stratify Crohn’s patients with spondyloarthritis symptoms as well as patients at risk,” said senior author Dr. Longman, assistant professor of medicine and director of the Jill Roberts Institute Longman Lab at Weill Cornell Medicine. Read more here.