Bacteria in the gut may be a contributory factor to an immune response that can lead to rheumatoid arthritis, proposes a study done on mice.
Our gut, like that of most mammals, is filled with thousands of species of bacteria, many of which are helpful and aid in the development of a normal, healthy immune system.
Gut-residing bacteria can also play a role in disorders of the immune system, especially autoimmune disorders in which the body attacks its own cells.
And it turns out that rheumatoid arthritis is one such disorder.
Researchers in the laboratories of Christophe Benoist and Diane Mathis at Harvard Medical School and Dan Littman at New York University made this discovery while working in mice prone to arthritis.
"In the absence of all bacteria, these mice didn't develop arthritis, but the introduction of a single bacterium was enough to jump-start the immune process that leads to development of the disease," says Mathis, an HMS professor of pathology.
The findings appear in the June 25 issue of the journal Immunity.