Role of Oral and Intestinal Microbiota in Rheumatoid Arthritis
Principal Investigators: Steven B. Abramson, MD, Dan. R. Littman, MD, PhD
Co-Investigators: Jose U. Scher, MD, Eric Pamer, MD, Michael Dustin, PhD, Walter Bretz, DDS
Gut microbiota have long been thought to contribute to inflammatory diseases, and multiple reports in animal models and humans suggest that antibiotic treatment alters autoimmune disease manifestations. We have recently demonstrated in rodents (Dr. Littman’s lab) that specific microbes induce the differentiation of Th17 cells in the intestinal lamina propria. There is strong genetic and therapy-based evidence that “pro-inflammatory” Th17 and “antiinflammatory” regulatory T cells (Treg) have critical roles in autoimmune diseases, including rheumatoid arthritis (RA), psoriatic arthritis (PsA), and Crohn’s disease. We are now studying the role of gut (intestinal and oral) microbiota (bacterial communities) in RA and other inflammatory arthritides. Our primary hypotheses are that: (1) characterization of Th17-inducing microbes in human intestine will provide insight into disease pathogenesis; and (2) directed manipulation of the gut microbiota will result in alteration of arthritis biofmarkers, including Th17/Treg balance.
|Insights attained may elucidate how the T cell network responds to microbial interactions with host intestinal components and provide a rationale for the development of new therapeutic approaches for RA. Three specific aims are proposed: (1) To create a multidisciplinary center to characterize human gut microbiome in patients with RA and related conditions: the first national Microbiome Center for Rheumatology and Autoimmunity (MiCRA); (2) To employ Th17-dependent mouse models of RA to study the role of microbiota/T cell interactions in development of disease and directly assess whether specific bacteria in RA patients can be implicated in disease pathogenesis; both direct bacterial cocktails and bacteria identified in RA patients will be inoculated into the mice; (3) To study the role of human gut microbiota in RA pathogenesis by (a) a cross-sectional study to determine whether a specific taxon or bacterial family in the human gut is associated with RA or PsA; (b) clinical and blood examinations to assess baseline disease activity, genetic predisposition, and immune cellular function of arthritis patients vs. controls; and (c) a prospective, interventional proof-of-concept biomarker study to determine whether alteration of the gut microbiota normalizes cellular immune functions in patients with RA.|
This project is funded by the National Institute of Musculoskeletal and Skin Diseases (NIAMS) and the NIH Office of the Director through the RC2-GO (Grand Opportunity) grant mechanism and is part of the Recovery Act of 2009 stimulus package. It is also consistent with the goals of the Human Microbiome Project (HMP), a major NIH Roadmap initiative, and has the potential to be truly transformative by filling a fundamental knowledge gap regarding the cause of inflammatory arthritis. The results could transform our understanding of the relationships between microbes and humans, and lead to innovative diagnostic tests and future treatments.
More information about the study:
Relevant Links:NIH "GO" Grant
National Institute of Musculoskeletal and Skin Diseases (NIAMS)
Dr. Littman’s lab
Human Microbiome Project (HMP) website