Health and Disability

Investigators at Johns Hopkins report they have new evidence that a bacterium known to cause chronic inflammatory gum infections also triggers the inflammatory “autoimmune” response characteristic of chronic, joint-destroying rheumatoid arthritis (RA). The new findings have important implications for prevention and treatment of RA, say the researchers.

In a report on the work, published in the Dec. 14 edition of the journal Science Translational Medicine, the investigators say the common denominator they identified in periodontal disease (gum disease) and in many people with RA is Aggregatibacter actinomycetemcomitans. An infection with A. actinomycetemcomitans appears to induce the production of citrullinated proteins, which are suspected of activating the immune system and driving the cascade of events leading to RA.

“This is like putting together the last few pieces of a complicated jigsaw puzzle that has been worked on for many years,” says Felipe Andrade, M.D., Ph.D., the senior study investigator and associate professor of Medicine at the Johns Hopkins University School of Medicine.

“This research may be the closest we’ve come to uncovering the root cause of RA,” adds first author Maximilian F. Konig, M.D., a former Johns Hopkins University School of Medicine fellow now at Massachusetts General Hospital.